Sample records for early fermentation period

  1. Microbial community dynamics during fermentation of doenjang-meju, traditional Korean fermented soybean.

    PubMed

    Jung, Ji Young; Lee, Se Hee; Jeon, Che Ok

    2014-08-18

    Bacterial and fungal community dynamics, along with viable plate counts and water content, were investigated in the exterior and interior regions of doenjang-meju, traditional Korean fermented soybean, during its fermentation process. Measurement of viable cells showed that the meju molding equipment might be an important source of bacterial cells (mostly Bacillus) during doenjang-meju fermentation, whereas fungi might be mostly derived from the fermentation environment including incubation shelves, air, and rice straws. Community analysis using rRNA-targeted pyrosequencing revealed that Bacillus among bacteria and Mucor among fungi were predominant in both the exterior and interior regions of doenjang-meju during the early fermentation period. Bacteria such as Ignatzschineria, Myroides, Enterococcus, Corynebacterium, and Clostridium and fungi such as Geotrichum, Scopulariopsis, Monascus, Fusarium, and eventually Aspergillus were mainly detected as the fermentation progressed. Bacillus, an aerobic bacterial group, was predominant in the exterior regions during the entire fermentation period, while anaerobic, facultative anaerobic, and microaerobic bacteria including Enterococcus, Lactobacillus, Clostridium, Myroides, and Ignatzschineria were much more abundant in the interior regions. Principal component analysis (PCA) also indicated that the bacterial communities in the exterior and interior regions were clearly differentiated, suggesting that aeration might be an important factor in determining the bacterial communities during doenjang-meju fermentation. However, PCA showed that fungal communities were not separated in the exterior and interior regions and Pearson's correlation coefficients showed that the major fungal taxa had significantly positive (Mucor and Geotrichum) or negative (Aspergillus) correlations with the water content during doenjang-meju fermentation, indicating that water content might be a significant factor in determining the fungal

  2. Periodic peristalsis increasing acetone-butanol-ethanol productivity during simultaneous saccharification and fermentation of steam-exploded corn straw.

    PubMed

    Li, Jingwen; Wang, Lan; Chen, Hongzhang

    2016-11-01

    The acetone-butanol-ethanol (ABE) fermentation of lignocellulose at high solids content has recently attracted extensive attention. However, the productivity of high solids ABE fermentation of lignocellulose is typically low in traditional processes due to the lack of efficient intensifying methods. In the present study, periodic peristalsis, a novel intensifying method, was applied to improve ABE production by the simultaneous saccharification and fermentation (SSF) of steam-exploded corn straw using Clostridium acetobutylicum ATCC824. The ABE concentration and the ABE productivity of SSF at a solids content of 17.5% (w/w) with periodic peristalsis were 17.1 g/L and 0.20 g/(L h), respectively, which were higher than those obtained under static conditions (15.2 g/L and 0.14 g/(L h)). The initial sugar conversion rate over the first 12 h with periodic peristalsis was 4.67 g/(L h) at 10 FPU/g cellulase dosage and 15% (w/w) solids content, an increase of 49.7% compared with the static conditions. With periodic peristalsis, the period of batch fermentation was shortened from 108 h to 84 h. The optimal operating regime was a low frequency (6 h -1 ) of periodic peristalsis in the acid-production phase (0-48 h) of SSF. Therefore, periodic peristalsis should be an effective intensifying method to increase the productivity of ABE fermentation at high solids content. Copyright © 2016 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  3. Microbial succession and metabolite changes during fermentation of dongchimi, traditional Korean watery kimchi.

    PubMed

    Jeong, Sang Hyeon; Jung, Ji Young; Lee, Se Hee; Jin, Hyun Mi; Jeon, Che Ok

    2013-06-03

    Dongchimi, one of the most common types of watery kimchi in Korea, was prepared using radish and its pH values, microbial cell numbers, bacterial communities, and metabolites were monitored periodically to investigate the fermentation process of watery kimchi. The bacterial abundance increased quickly during the early fermentation period and the pH values concurrently decreased rapidly without any initial pH increase. After 15 days of fermentation, the bacterial abundance decreased rapidly with the increase of Saccharomyces abundance and then increased again with a decrease of Saccharomyces abundance after 40 days of fermentation, suggesting that bacteria and Saccharomyces have a direct antagonistic relationship. Finally, after 60 days of fermentation, a decrease in bacterial abundance and the growth of Candida were concurrently observed. Community analysis using pyrosequencing revealed that diverse genera such as Leuconostoc, Lactobacillus, Pseudomonas, Pantoea, and Weissella were present at initial fermentation (day 0), but Leuconostoc became predominant within only three days of fermentation and remained predominant until the end of fermentation (day 100). Metabolite analysis using (1)H NMR showed that the concentrations of free sugars (fructose and glucose) were very low during the early fermentation period, but their concentrations increased rapidly although lactate, mannitol, and acetate were produced. After 30 days of fermentation, quick consumption of free sugars and production of glycerol and ethanol were observed concurrently with the growth of Saccharomyces, levels of which might be considered for use as a potential indicator of dongchimi quality and fermentation time. Copyright © 2013 Elsevier B.V. All rights reserved.

  4. Profiling of dynamic changes in the microbial community during the soy sauce fermentation process.

    PubMed

    Wei, Quanzeng; Wang, Hongbin; Chen, Zhixin; Lv, Zhijia; Xie, Yufeng; Lu, Fuping

    2013-10-01

    Soy sauce is a traditional condiment manufactured by natural inoculation and mixed culture fermentation. As is well known, it is the microbial community that plays an important role in the formation of its flavors. However, to date, its dynamic changes during the long period of fermentation process are still unclear, intensively constraining the improvement and control of the soy sauce quality. In this work, we revealed the dynamic changes of the microbial community by combining a cultured dependent method and a cultured independent method of polymerase chain reaction (PCR)-denaturing gradient gel electrophoresis. Results indicated that the two methods verified and complemented each other in profiling microbial community, and that significant dynamics of the microbial community existed during the fermentation process, especially the strong inhibition of the growth of most of the microbes when entering into the mash stage from the koji stage. In the analysis of bacterial community, Staphylococcus and Bacillus were found to be the dominant bacteria and detected in the whole fermentation process. Kurthia and Klebsiella began to appear in the koji stage and then fade away in the early stage of the mash fermentation. In the analysis of fungal community, Aspergillus sojae and Zygosaccharomyces rouxii were found to be the dominant fungi in the koji and mash fermentation, respectively. It was clearly shown that when A. sojae decreased and disappeared in the middle stage of the mash fermentation, Z. rouxii appeared and increased at the meantime. Aspergillus parasiticus, Trichosporon ovoides and Trichosporon asahii also appeared in the koji and the early period of the mash fermentation and disappeared thereafter. Similar to Z. rouxii, Millerozyma farinosa and Peronospora farinosa were also found spontaneously which appeared in the mid-late period of the mash fermentation. The principal component analysis suggested that the microbial community underwent significant changes in

  5. Evaluation of physicochemical properties and antioxidant activities of kombucha "Tea Fungus" during extended periods of fermentation.

    PubMed

    Amarasinghe, Hashani; Weerakkody, Nimsha S; Waisundara, Viduranga Y

    2018-05-01

    Kombucha fermentation is traditionally carried out by inoculating a previously grown tea fungal mat into a freshly prepared tea broth and incubating under aerobic conditions for 7-10 days. In this study, four kombucha beverages were prepared by placing the tea fungal mats in sugared Sri Lankan black tea at varying concentrations for a period of 8 weeks. The antioxidant activities, physicochemical, and qualitative properties were monitored prior to the commencement of the fermentation process, one day after the inoculation with the microorganisms and subsequently on a weekly basis. All samples displayed a statistically significant decrease ( p  <   .05) in the antioxidant activity at the end of 8 weeks, which was indicative of the decreasing functional properties of the beverage. The physicochemical properties indicated increased acidity and turbidity, which might decrease consumer appeal of the fermented beverage. Further studies are necessary to test the accumulation of organic acids, nucleic acids, and toxicity of kombucha on human organs following the extended period of fermentation.

  6. Effects of different ratios and storage periods of liquid brewer's yeast mixed with cassava pulp on chemical composition, fermentation quality and in vitro ruminal fermentation.

    PubMed

    Kamphayae, Sukanya; Kumagai, Hajime; Angthong, Wanna; Narmseelee, Ramphrai; Bureenok, Smerjai

    2017-04-01

    This study aims to evaluate the chemical composition, fermentation quality and in vitro ruminal fermentation of various ratios and storage periods of liquid brewer's yeast (LBY) mixed with cassava pulp (CVP). Four mixtures of fresh LBY and CVP were made (LBY0, LBY10, LBY20, and LBY30 for LBY:CVP at 0:100, 10:90, 20:80, and 30:70, respectively) on a fresh matter basis, in 500 g in plastic bags and stored at 30 to 32°C. After storage, the bags were opened weekly from weeks 0 to 4. Fermentation quality and in vitro gas production (IVGP) were determined, as well as the dry matter (DM), organic matter (OM), crude protein (CP), ether extract (EE), neutral detergent fiber, acid detergent fiber and acid detergent lignin contents. The contents of CP and EE increased, whereas all other components decreased, in proportion to LBY inclusion (p<0.01). The DM and OM contents gradually decreased in weeks 3 and 4 (p<0.05), while EE contents were lowest in week 0. The pH, ammonia nitrogen per total nitrogen (NH 3 -N/TN) and V-score in each mixture and storage period demonstrated superior fermentation quality (pH≤4.2, NH 3 -N/TN≤12.5%, and V-score>90%). The pH increased and NH 3 -N/TN decreased, with proportionate increases of LBY, whereas the pH decreased and NH 3 -N/TN increased, as the storage periods were extended (p<0.01). Although IVGP decreased in proportion to the amount of LBY inclusion (p<0.01), in vitro organic matter digestibility (IVOMD) was unaffected by the mixture ratios. The highest IVGP and IVOMD were observed in week 0 (p<0.01). The inclusion of LBY (as high as 30%) into CVP improves the chemical composition of the mixture, thereby increasing the CP content, while decreasing IVGP, without decreasing fermentation quality and IVOMD. In addition, a preservation period of up to four weeks can guarantee superior fermentation quality in all types of mixtures. Therefore, we recommend limiting the use of CVP as a feed ingredient, given its low nutritional value and

  7. Effect of Periodic Water Addition on Citric Acid Production in Solid State Fermentation

    NASA Astrophysics Data System (ADS)

    Utpat, Shraddha S.; Kinnige, Pallavi T.; Dhamole, Pradip B.

    2013-09-01

    Water addition is one of the methods used to control the moisture loss in solid state fermentation (SSF). However, none of the studies report the timing of water addition and amount of water to be added in SSF. Therefore, this work was undertaken with an objective to evaluate the performance of periodic water addition on citric acid production in SSF. Experiments were conducted at different moistures (50-80 %) and temperatures (30-40 °C) to simulate the conditions in a fermenter. Citric acid production by Aspergillus niger (ATCC 9029) using sugarcane baggase was chosen as a model system. Based on the moisture profile, citric acid and sugar data, a strategy was designed for periodic addition of water. Water addition at 48, 96, 144 and 192 h enhanced the citric acid production by 62 % whereas water addition at 72, 120, and 168 h increased the citric acid production by just 17 %.

  8. Deriving fractional rate of degradation of logistic-exponential (LE) model to evaluate early in vitro fermentation.

    PubMed

    Wang, M; Sun, X Z; Tang, S X; Tan, Z L; Pacheco, D

    2013-06-01

    Water-soluble components of feedstuffs are mainly utilized during the early phase of microbial fermentation, which could be deemed an important determinant of gas production behavior in vitro. Many studies proposed that the fractional rate of degradation (FRD) estimated by fitting gas production curves to mathematical models might be used to characterize the early incubation for in vitro systems. In this study, the mathematical concept of FRD was developed on the basis of the Logistic-Exponential (LE) model, with initial gas volume being zero (LE0). The FRD of the LE0 model exhibits a continuous increase from initial (FRD 0) toward final asymptotic value (FRD F) with longer incubation time. The relationships between the FRD and gas production at incubation times 2, 4, 6, 8, 12 and 24 h were compared for four models, in addition to LE0, Generalization of the Mitscherlich (GM), c th order Michaelis-Menten (MM) and Exponential with a discrete LAG (EXPLAG). A total of 94 in vitro gas curves from four subsets with a wide range of feedstuffs from different laboratories and incubation periods were used for model testing. Results indicated that compared with the GM, MM and EXPLAG models, the FRD of LE0 model consistently had stronger correlations with gas production across the four subsets, especially at incubation times 2, 4, 6, 8 and 12 h. Thus, the LE0 model was deemed to provide a better representation of the early fermentation rates. Furthermore, the FRD 0 also exhibited strong correlations (P < 0.05) with gas production at early incubation times 2, 4, 6 and 8 h across all four subsets. In summary, the FRD of LE0 model provides an alternative to quantify the rate of early stage incubation, and its initial value could be an important starting parameter of rate.

  9. Analysis of microbiota involved in the aged natural fermentation of indigo.

    PubMed

    Okamoto, Takahiro; Aino, Kenichi; Narihiro, Takashi; Matsuyama, Hidetoshi; Yumoto, Isao

    2017-04-01

    Although the indigo reduction process is performed via natural fermentation and maintained under open-air condition, the indigo-reducing reactions continue for 6 months (on average) or longer. Identifying the mechanism underlying the maintenance of this process could lead to the development of a novel, long-lasting, unsterilized bioprocesses. To determine the mechanisms underlying the maintenance of the indigo fermentation system microbiota for more than 6 months in a reduced state in an anaerobic alkaline environment, we examined changes in the microbiota in one early-phase batch and two aged batches of indigo fermentation fluid. The microbiota in the aged fermentation fluid consisted mainly of the genera Alkalibacterium, Amphibacillus, Anaerobacillus and Polygonibacillus and the family Proteinivoraceae. The genera Alkalibacterium, Amphibacillus and Polygonibacillus are known to include indigo-reducing bacteria. Although the transition speed was slower in the aged fermentation fluid than in the early-stage fluid, the microbiota in the aged fermentation fluid maintained for more than 6 months was drastically changed within a period of 3 months. The results of this study indicate that the bacterial consortia consisted of various indigo-reducing species that replace the previous group of indigo-reducing bacteria. The notable transitional changes may be concomitant with changes in the environmental conditions, such as the nutritional conditions, observed over 3 months. This flexibility may lead to important changes in the microbiota that allow for the maintenance of a fermentation-reducing state over a long period.

  10. Effects of gas periodic stimulation on key enzyme activity in gas double-dynamic solid state fermentation (GDD-SSF).

    PubMed

    Chen, Hongzhang; Shao, Meixue; Li, Hongqiang

    2014-03-05

    The heat and mass transfer have been proved to be the important factors in air pressure pulsation for cellulase production. However, as process of enzyme secretion, the cellulase formation has not been studied in the view of microorganism metabolism and metabolic key enzyme activity under air pressure pulsation condition. Two fermentation methods in ATPase activity, cellulase productivity, weight lose rate and membrane permeability were systematically compared. Results indicated that gas double-dynamic solid state fermentation had no obviously effect on cell membrane permeability. However, the relation between ATPase activity and weight loss rate was linearly dependent with r=0.9784. Meanwhile, the results also implied that gas periodic stimulation had apparently strengthened microbial metabolism through increasing ATPase activity during gas double-dynamic solid state fermentation, resulting in motivating the production of cellulase by Trichoderma reesei YG3. Therefore, the increase of ATPase activity would be another crucial factor to strengthen fermentation process for cellulase production under gas double-dynamic solid state fermentation. Copyright © 2013 Elsevier Inc. All rights reserved.

  11. Controlling grape must fermentation in early winemaking phases: the role of electrochemical treatment.

    PubMed

    Lustrato, G; Alfano, G; Belli, C; Grazia, L; Iorizzo, M; Maiuro, L; Massarella, F; Zanardini, E; Ranalli, G

    2003-01-01

    To contribute to an understanding of the phenomena related to the effect of low electric current (LEC) in grape must fermentation during laboratory and pilot plant scale winemaking, with selected co-culture yeasts (Saccharomyces cerevisiae strain 404 and Hanseniaspora guilliermodii strain 465). LEC (10, 30, 50 and 100 mA) was applied to fresh grape must as an alternative method to the usual addition of SO2. Parameters such as polarity, treatment duration (24-96 h) and type of inoculum yeast were varied one at a time. LEC decreased the survival time and increased the death rate of H. guilliermondii strain 465 in co-cultures, whereas it did not affect the growth and survival of S. cerevisiae strain 40. A final comparison was made of the main physico-chemical parameters on wine obtained after the different tests. The results have demonstrated that the low voltage treatment using a pair of graphite electrodes had a positive effect on grape juice fermentation (yeast microflora) during the early stages of winemaking, even with the potential of being an alternative method to the usual addition of SO2. These results could be of significant importance in developing new winemaking technologies for an innovative yeast fermentation control process for 'biological wine'.

  12. Transcription profile of brewery yeast under fermentation conditions.

    PubMed

    James, T C; Campbell, S; Donnelly, D; Bond, U

    2003-01-01

    Yeast strains, used in the brewing industry, experience distinctive physiological conditions. During a brewing fermentation, yeast are exposed to anaerobic conditions, high pressure, high specific gravity and low temperatures. The purpose of this study was to examine the global gene expression profile of yeast subjected to brewing stress. We have carried out a microarray analysis of a typical brewer's yeast during the course of an 8-day fermentation in 15 degrees P wort. We used the probes derived from Saccharomyces cerevisiae genomic DNA on the chip and RNA isolated from three stages of brewing. This analysis shows a high level of expression of genes involved in fatty acid and ergosterol biosynthesis early in fermentation. Furthermore, genes involved in respiration and mitochondrial protein synthesis also show higher levels of expression. Surprisingly, we observed a complete repression of many stress response genes and genes involved in protein synthesis throughout the 8-day period compared with that at the start of fermentation. This microarray data set provides an analysis of gene expression under brewing fermentation conditions. The data provide an insight into the various metabolic processes altered or activated by brewing conditions of growth. This study leads to future experiments whereby selective alterations in brewing conditions could be introduced to take advantage of the changing transcript profile to improve the quality of the brew.

  13. The process-related dynamics of microbial community during a simulated fermentation of Chinese strong-flavored liquor.

    PubMed

    Zhang, Yanyan; Zhu, Xiaoyu; Li, Xiangzhen; Tao, Yong; Jia, Jia; He, Xiaohong

    2017-09-15

    Famous Chinese strong-flavored liquor (CSFL) is brewed by microbial consortia in a special fermentation pit (FT). However, the fermentation process was not fully understood owing to the complicate community structure and metabolism. In this study, the process-related dynamics of microbial communities and main flavor compounds during the 70-day fermentation process were investigated in a simulated fermentation system. A three-phase model was proposed to characterize the process of the CSFL fermentation. (i) In the early fermentation period (1-23 days), glucose was produced from macromolecular carbohydrates (e.g., starch). The prokaryotic diversity decreased significantly. The Lactobacillaceae gradually predominated in the prokaryotic community. In contrast, the eukaryotic diversity rose remarkably in this stage. Thermoascus, Aspergillus, Rhizopus and unidentified Saccharomycetales were dominant eukaryotic members. (ii) In the middle fermentation period (23-48 days), glucose concentration decreased while lactate acid and ethanol increased significantly. Prokaryotic community was almost dominated by the Lactobacillus, while eukaryotic community was mainly comprised of Thermoascus, Emericella and Aspergillus. (iii) In the later fermentation period (48-70 days), the concentrations of ethyl esters, especially ethyl caproate, increased remarkably. The CSFL fermentation could undergo three stages: saccharification, glycolysis and esterification. Saccharomycetales, Monascus, and Rhizopus were positively correlated to glucose concentration (P < 0.05), highlighting their important roles in the starch saccharification. The Lactobacillaceae, Bacilli, Botryotinia, Aspergillus, unidentified Pleosporales and Capnodiales contributed to the glycolysis and esterification, because they were positively correlated to most organic acids and ethyl esters (P < 0.05). Additionally, four genera, including Emericella, Suillus, Mortierella and Botryotinia, that likely played key roles

  14. Effects of red pepper powder on microbial communities and metabolites during kimchi fermentation.

    PubMed

    Jeong, Sang Hyeon; Lee, Hyo Jung; Jung, Ji Young; Lee, Se Hee; Seo, Hye-Young; Park, Wan-Soo; Jeon, Che Ok

    2013-01-01

    To investigate the effects of red pepper powder on kimchi fermentation, Baechu (Chinese cabbage) and Mu (radish) kimchi, with and without red pepper powder, were prepared and their characteristics, including pH, colony-forming units (CFU), microbial communities, and metabolites, were periodically monitored for 40days. Measurements of pH and CFU showed that the lag phases of kimchi fermentation were clearly extended by the addition of red pepper powder. Microbial community analysis using a barcoded pyrosequencing analysis showed that the bacterial diversities in kimchi with red pepper powder decreased more slowly than kimchi without red pepper powder as kimchi fermentation progressed. The kimchi microbial communities were represented mainly by the genera Leuconostoc and Lactobacillus in all kimchi, and the abundance of Weissella was negligible in kimchi without red pepper powder. However, interestingly, kimchi with red pepper powder contained much higher proportions of Weissella than kimchi without red pepper powder, while the proportions of Leuconostoc and Lactobacillus were evidently lower in kimchi with red pepper powder compared to kimchi without red pepper powder. Metabolite analysis using a (1)H NMR technique also showed that the fermentation of kimchi with red pepper powder progressed a little more slowly than that of kimchi without red pepper powder. Principle component analysis using microbial communities and metabolites supported the finding that the addition of red pepper powder into kimchi resulted in the slowing of the kimchi fermentation process, especially during the early fermentation period and influenced the microbial succession and metabolite production during the kimchi fermentation processes. Copyright © 2012 Elsevier B.V. All rights reserved.

  15. Dynamics of microbial community during the extremely long-term fermentation process of a traditional soy sauce.

    PubMed

    Yang, Yang; Deng, Yue; Jin, Yulan; Liu, Yanxi; Xia, Baixue; Sun, Qun

    2017-08-01

    Soy sauce produced by long-term natural fermentation is a traditional specialty in Asia, with a reputation for superior quality and rich flavour. In this study, both culture-dependent and culture-independent approaches were used to investigate the microbial diversity and community dynamics during an extremely long-term (up to 4 years) natural fermentation of Xianshi Soy Sauce, a national intangible cultural heritage. Genera of Bacillus, Aspergillus and Cladosporium were detected by both methods above. The relative abundance of the genera Bacillus and Weissella was significantly higher in the late stage than in the early one, while the genera Klebsiella and Shimwellia were opposite (P < 0.05). For microbial community structure, subsequent analyses showed that obvious changes occurred with fermentation time, while there was a fair homogeneousness among samples of the same year, especially during the late fermentation stage. The clustering analysis tended to separate the fermented mashes of the 4th year from the earlier stages, suggesting the necessity of the long fermentation period for developing distinctive microbiota and characteristic quality-related compounds. This is the first report to explore the temporal changes in microbial dynamics over a period of 4 years in traditional fermentation of soy sauce, and this work illustrated the importance of isolation of appropriate strains to be used as starter cultures in brewing processes. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

  16. In vitro batch fecal fermentation comparison of gas and short-chain fatty acid production using "slowly fermentable" dietary fibers.

    PubMed

    Kaur, Amandeep; Rose, Devin J; Rumpagaporn, Pinthip; Patterson, John A; Hamaker, Bruce R

    2011-01-01

    Sustained colonic fermentation supplies beneficial fermentative by-products to the distal colon, which is particularly prone to intestinal ailments. Blunted/delayed initial fermentation may also lead to less bloating. Previously, we reported that starch-entrapped alginate-based microspheres act as a slowly fermenting dietary fiber. This material was used in the present study to provide a benchmark to compare to other "slowly fermentable" fibers. Dietary fibers with previous reports of slow fermentation, namely, long-chain inulin, psyllium, alkali-soluble corn bran arabinoxylan, and long-chain β-glucan, as well as starch-entrapped microspheres were subjected to in vitro upper gastrointestinal digestion and human fecal fermentation and measured over 48 h for pH, gas, and short-chain fatty acids (SCFA). The resistant fraction of cooked and cooled potato starch was used as another form of fermentable starch and fructooligosaccharides (FOS) served as a fast fermenting control. Corn bran arabinoxylan and long-chain β-glucan initially appeared slower fermenting with comparatively low gas and SCFA production, but later fermented rapidly with little remaining in the final half of the fermentation period. Long-chain inulin and psyllium had slow and moderate, but incomplete, fermentation. The resistant fraction of cooked and cooled potato starch fermented rapidly and appeared similar to FOS. In conclusion, compared to the benchmark slowly fermentable starch-entrapped microspheres, a number of the purported slowly fermentable fibers fermented fairly rapidly overall and, of this group, only the starch-entrapped microspheres appreciably fermented in the second half of the fermentation period. Consumption of dietary fibers, particularly commercial prebiotics, leads to uncomfortable feelings of bloating and flatulence due to their rapid degradation in our large intestine. This article employs claimed potential slowly fermenting fibers and compares their fermentation rates

  17. Early transcriptional response to biotic stress in mixed starter fermentations involving Saccharomyces cerevisiae and Torulaspora delbrueckii.

    PubMed

    Tronchoni, Jordi; Curiel, Jose Antonio; Morales, Pilar; Torres-Pérez, Rafael; Gonzalez, Ramon

    2017-01-16

    Advances in microbial wine biotechnology have led to the recent commercialization of several non-Saccharomyces starter cultures. These are intended to be used in either simultaneous or sequential inoculation with Saccharomyces cerevisiae. The different types of microbial interactions that can be stablished during wine fermentation acquire an increased relevance in the context of these mixed-starter fermentations. We analysed the transcriptional response to co-cultivation of S. cerevisiae and Torulaspora delbrueckii. The study focused in the initial stages of wine fermentation, before S. cerevisiae completely dominates the mixed cultures. Both species showed a clear response to the presence of each other, even though the portion of the genome showing altered transcription levels was relatively small. Changes in the transcription pattern suggested a stimulation of metabolic activity and growth, as a consequence of the presence of competitors in the same medium. The response of S. cerevisiae seems to take place earlier, as compared to T. delbrueckii. Enhanced glycolytic activity of the mixed culture was confirmed by the CO 2 production profile during these early stages of fermentation. Interestingly, HSP12 expression appeared induced by co-cultivation for both of S. cerevisiae and Torulaspora delbrueckii in the two time points studied. This might be related with a recently described role of Hsp12 in intercellular communication in yeast. Expression of S. cerevisiae PAU genes was also stimulated in mixed cultures. Copyright © 2016. Published by Elsevier B.V.

  18. Cell growth behaviors of Clostridium acetobutylicum in a pervaporation membrane bioreactor for butanol fermentation.

    PubMed

    Yao, Peina; Xiao, Zeyi; Chen, Chunyan; Li, Weijia; Deng, Qing

    2016-01-01

    Acetone-butanol-ethanol fermentation using Clostridium acetobutylicum was studied in the continuous and closed-circulating fermentation (CCCF) system. The experiment lasting for 192 H was carried out by integrating fermentation with in situ pervaporation. In the entire process, the cell growth profile took place in the following two phases: the logarithmic phase during early 28 H and the linear phase from 130 to 150 H. This was a unique characteristic compared with the curve of traditional fermentation, and the fitting equations of two growth phases were obtained by Origin software according to the kinetic model of cell growth. Besides, the kinetic parameters that include the butanol yield, maximum specific growth rate, average specific formation rate, and volumetric productivity of butanol were measured as 0.19 g g(-1) , 0.345 H(-1) , 0.134 H(-1) and 0.23 g L(-1)  H(-1) , respectively. The C. acetobutylicum in the CCCF system showed good adaptability and fermentation performance, and the prolonged fermentation period and high production were also the main advantages of CCCF technology. © 2014 International Union of Biochemistry and Molecular Biology, Inc.

  19. Exploring microbial succession and diversity during solid-state fermentation of Tianjin duliu mature vinegar.

    PubMed

    Nie, Zhiqiang; Zheng, Yu; Wang, Min; Han, Yue; Wang, Yuenan; Luo, Jianmei; Niu, Dandan

    2013-11-01

    Tianjin duliu mature vinegar was one of famous Chinese traditional vinegars. The unique flavor and taste of vinegar are mainly generated by the multitudinous microorganisms during fermentation. In this research, the composition and succession of microbial communities in the entire solid-state fermentation were investigated, including starter daqu and acetic acid fermentation (AAF). Molds and yeasts in daqu, including Aspergillus, Saccharomycopsis and Pichia, decreased in AAF. The bacterial compositions increased from four genera in daqu to more than 13 genera in AAF. Principal component analysis showed that Acetobacter, Gluconacetobacter, Lactobacillus and Nostoc were dominant bacteria that were correlated well with AAF process. In the early fermentation period, lactic acid bacteria (LAB) decreased while acetic acid bacteria and Nostoc increased rapidly with the accumulation of total acids. Then, the abundance and diversity of LAB increased (more than 80%), indicating that LAB had important influences on the flavor and taste of vinegar. Copyright © 2013 Elsevier Ltd. All rights reserved.

  20. Genome-wide study of the adaptation of Saccharomyces cerevisiae to the early stages of wine fermentation.

    PubMed

    Novo, Maite; Mangado, Ana; Quirós, Manuel; Morales, Pilar; Salvadó, Zoel; Gonzalez, Ramon

    2013-01-01

    This work was designed to identify yeast cellular functions specifically affected by the stress factors predominating during the early stages of wine fermentation, and genes required for optimal growth under these conditions. The main experimental method was quantitative fitness analysis by means of competition experiments in continuous culture of whole genome barcoded yeast knockout collections. This methodology allowed the identification of haploinsufficient genes, and homozygous deletions resulting in growth impairment in synthetic must. However, genes identified as haploproficient, or homozygous deletions resulting in fitness advantage, were of little predictive power concerning optimal growth in this medium. The relevance of these functions for enological performance of yeast was assessed in batch cultures with single strains. Previous studies addressing yeast adaptation to winemaking conditions by quantitative fitness analysis were not specifically focused on the proliferative stages. In some instances our results highlight the importance of genes not previously linked to winemaking. In other cases they are complementary to those reported in previous studies concerning, for example, the relevance of some genes involved in vacuolar, peroxisomal, or ribosomal functions. Our results indicate that adaptation to the quickly changing growth conditions during grape must fermentation require the function of different gene sets in different moments of the process. Transport processes and glucose signaling seem to be negatively affected by the stress factors encountered by yeast in synthetic must. Vacuolar activity is important for continued growth during the transition to stationary phase. Finally, reduced biogenesis of peroxisomes also seems to be advantageous. However, in contrast to what was described for later stages, reduced protein synthesis is not advantageous for the early (proliferative) stages of the fermentation process. Finally, we found adenine and lysine

  1. Periodic Early Childhood Hearing Screening: The EHDI Perspective

    ERIC Educational Resources Information Center

    Hoffman, Jeff; Houston, K. Todd; Munoz, Karen F.; Bradham, Tamala S.

    2011-01-01

    State coordinators of early hearing detection and intervention (EHDI) programs completed a strengths, weaknesses, opportunities, and threats, or SWOT, analysis that examined 12 areas within state EHDI programs. Concerning periodic early childhood hearing screening, 47 coordinators listed 241 items and themes were identified within each SWOT…

  2. Discovery and History of Amino Acid Fermentation.

    PubMed

    Hashimoto, Shin-Ichi

    There has been a strong demand in Japan and East Asia for L-glutamic acid as a seasoning since monosodium glutamate was found to present umami taste in 1907. The discovery of glutamate fermentation by Corynebacterium glutamicum in 1956 enabled abundant and low-cost production of the amino acid, creating a large market. The discovery also prompted researchers to develop fermentative production processes for other L-amino acids, such as lysine. Currently, the amino acid fermentation industry is so huge that more than 5 million metric tons of amino acids are manufactured annually all over the world, and this number continues to grow. Research on amino acid fermentation fostered the notion and skills of metabolic engineering which has been applied for the production of other compounds from renewable resources. The discovery of glutamate fermentation has had revolutionary impacts on both the industry and science. In this chapter, the history and development of glutamate fermentation, including the very early stage of fermentation of other amino acids, are reviewed.

  3. Optimization of fermentation parameters for production of ethanol from kinnow waste and banana peels by simultaneous saccharification and fermentation.

    PubMed

    Sharma, Naresh; Kalra, K L; Oberoi, Harinder Singh; Bansal, Sunil

    2007-12-01

    A study was taken up to evaluate the role of some fermentation parameters like inoculum concentration, temperature, incubation period and agitation time on ethanol production from kinnow waste and banana peels by simultaneous saccharification and fermentation using cellulase and co-culture of Saccharomyces cerevisiae G and Pachysolen tannophilus MTCC 1077. Steam pretreated kinnow waste and banana peels were used as substrate for ethanol production in the ratio 4:6 (kinnow waste: banana peels). Temperature of 30°C, inoculum size of S. cerevisiae G 6% and (v/v) Pachysolen tannophilus MTCC 1077 4% (v/v), incubation period of 48 h and agitation for the first 24 h were found to be best for ethanol production using the combination of two wastes. The pretreated steam exploded biomass after enzymatic saccharification containing 63 gL(-1) reducing sugars was fermented with both hexose and pentose fermenting yeast strains under optimized conditions resulting in ethanol production, yield and fermentation efficiency of 26.84 gL(-1), 0.426 gg (-1) and 83.52 % respectively. This study could establish the effective utilization of kinnow waste and banana peels for bioethanol production using optimized fermentation parameters.

  4. Microbial Successions and Metabolite Changes during Fermentation of Salted Shrimp (Saeu-Jeot) with Different Salt Concentrations

    PubMed Central

    Lee, Se Hee; Jung, Ji Young; Jeon, Che Ok

    2014-01-01

    To investigate the effects of salt concentration on saeu-jeot (salted shrimp) fermentation, four sets of saeu-jeot samples with 20%, 24%, 28%, and 32% salt concentrations were prepared, and the pH, bacterial and archaeal abundances, bacterial communities, and metabolites were monitored during the entire fermentation period. Quantitative PCR showed that Bacteria were much more abundant than Archaea in all saeu-jeot samples, suggesting that bacterial populations play more important roles than archaeal populations even in highly salted samples. Community analysis indicated that Vibrio, Photobacterium, Psychrobacter, Pseudoalteromonas, and Enterovibrio were identified as the initially dominant genera, and the bacterial successions were significantly different depending on the salt concentration. During the early fermentation period, Salinivibrio predominated in the 20% salted samples, whereas Staphylococcus, Halomonas, and Salimicrobium predominated in the 24% salted samples; eventually, Halanaerobium predominated in the 20% and 24% salted samples. The initially dominant genera gradually decreased as the fermentation progressed in the 28% and 32% salted samples, and eventually Salimicrobium became predominant in the 28% salted samples. However, the initially dominant genera still remained until the end of fermentation in the 32% salted samples. Metabolite analysis showed that the amino acid profile and the initial glycerol increase were similar in all saeu-jeot samples regardless of the salt concentration. After 30–80 days of fermentation, the levels of acetate, butyrate, and methylamines in the 20% and 24% salted samples increased with the growth of Halanaerobium, even though the amino acid concentrations steadily increased until approximately 80–107 days of fermentation. This study suggests that a range of 24–28% salt concentration in saeu-jeot fermentation is appropriate for the production of safe and tasty saeu-jeot. PMID:24587230

  5. Commercialization of a novel fermentation concept.

    PubMed

    Mazumdar-Shaw, Kiran; Suryanarayan, Shrikumar

    2003-01-01

    Fermentation is the core of biotechnology where current methodologies span across technologies based on the use of either solid or liquid substrates. Traditionally, solid substrate fermentation technologies have been the widely practiced in the Far East to manufacture fermented foods such as soya sauce, sake etc. The Western World briefly used solid substrate fermentation for the manufacture of antibiotics and enzymes but rapidly replaced this technology with submerged fermentation which proved to be a superior technology in terms of automation, containment and large volume fermentation. Biocon India developed its enzyme technology based on solid substrate fermentation as a low-cost, low-energy option for the production of specialty enzymes. However, the limitations of applying solid substrate fermentation to more sophisticated biotechnology products as well as large volume fermentations were recognized by Biocon India as early as 1990 and the company embarked on a 8 year research and development program to develop a novel bioreactor capable of conducting solid substrate fermentation with comparable levels of automation and containment as those practiced by submerged fermentation. In addition, the novel technology enabled fed-batch fermentation, in situ extraction and other enabling features that will be discussed in this article. The novel bioreactor was christened the "PlaFractor" (pronounced play-fractor). The next level of research on this novel technology is now focused on addressing large volume fermentation. This article traces the evolution of Biocon India's original solid substrate fermentation to the PlaFractor technology and provides details of the scale-up and commercialization processes that were involved therein. What is also apparent in the article is Biocon India's commercially focused research programs and the perceived need to be globally competitive through low costs of innovation that address, at all times, processes and technologies that

  6. Early alcohol exposure impairs ocular dominance plasticity throughout the critical period.

    PubMed

    Medina, Alexandre E; Ramoa, Ary S

    2005-06-09

    Animal models of fetal alcohol syndrome (FAS) have revealed an impairment of sensory neocortex plasticity. Here, we examine whether early alcohol exposure leads to a permanent impairment of ocular dominance plasticity (OD) or to an alteration in the timing of the critical period. Ferrets were exposed to alcohol during a brief period of development prior to eye opening and effects of monocular deprivation examined during early, mid and late critical period. Single-unit electrophysiology revealed markedly reduced OD plasticity at every age examined. This finding provides evidence that early alcohol exposure does not affect the timing or duration of the critical period of OD plasticity and suggests an enduring impairment of neural plasticity in FAS.

  7. Coupling of Spinosad Fermentation and Separation Process via Two-Step Macroporous Resin Adsorption Method.

    PubMed

    Zhao, Fanglong; Zhang, Chuanbo; Yin, Jing; Shen, Yueqi; Lu, Wenyu

    2015-08-01

    In this paper, a two-step resin adsorption technology was investigated for spinosad production and separation as follows: the first step resin addition into the fermentor at early cultivation period to decrease the timely product concentration in the broth; the second step of resin addition was used after fermentation to adsorb and extract the spinosad. Based on this, a two-step macroporous resin adsorption-membrane separation process for spinosad fermentation, separation, and purification was established. Spinosad concentration in 5-L fermentor increased by 14.45 % after adding 50 g/L macroporous at the beginning of fermentation. The established two-step macroporous resin adsorption-membrane separation process got the 95.43 % purity and 87 % yield for spinosad, which were both higher than that of the conventional crystallization of spinosad from aqueous phase that were 93.23 and 79.15 % separately. The two-step macroporous resin adsorption method has not only carried out the coupling of spinosad fermentation and separation but also increased spinosad productivity. In addition, the two-step macroporous resin adsorption-membrane separation process performs better in spinosad yield and purity.

  8. 78 FR 21979 - Early Career Doctorates Survey; Extension of Public Comment Period

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-04-12

    ... NATIONAL SCIENCE FOUNDATION Early Career Doctorates Survey; Extension of Public Comment Period AGENCY: National Science Foundation. ACTION: Notification of Extension of Public Comment Period. SUMMARY... on establishing the Early Career Doctorates Survey. The original comment date was to end on May 9...

  9. Efficient arachidonic acid-rich oil production by Mortierella alpina through a repeated fed-batch fermentation strategy.

    PubMed

    Ji, Xiao-Jun; Zhang, Ai-Hui; Nie, Zhi-Kui; Wu, Wen-Jia; Ren, Lu-Jing; Huang, He

    2014-10-01

    Arachidonic acid (ARA)-rich oil production by Mortierella alpina is a long fermentation period needed process due to the low growth rate of the filamentous fungus used. This causes the low productivity of ARA-rich oil and hinders its industrial mass scale production. In the present study, different fed-batch strategies were conducted to shorten the fermentation period. The result showed that compared with the batch culture, the fermentation period was shortened from 7days to 5days with the productivity of ARA-rich oil increased from 0.9g/(L·d) to 1.3g/(L·d) by using the fed-batch fermentation strategy. Furthermore, repeated fed-batch fermentation strategy was adopted to achieve the purpose of continuous production. By using this strategy, the fermentation period was shortened from 40days to 26days in a four cycle repeated fed-batch fermentation. This strategy proved to be convenient and economical for ARA-rich oil commercial production process. Copyright © 2014 Elsevier Ltd. All rights reserved.

  10. Changes in the bacterial community in the fermentation process of kôso, a Japanese sugar-vegetable fermented beverage.

    PubMed

    Chiou, Tai-Ying; Suda, Wataru; Oshima, Kenshiro; Hattori, Masahira; Takahashi, Tomoya

    2017-02-01

    Kôso is a Japanese fermented beverage made with over 20 kinds of vegetables, mushrooms, and sugars. The changes in the bacterial population of kôso during fermentation at 25 °C over a period of 10 days were studied using 454 pyrosequencing of the 16S rRNA gene. The analysis detected 224 operational taxonomic units (OTUs) clustered from 8 DNA samples collected on days 0, 3, 7, and 10 from two fermentation batches. Proteobacteria were the dominant phylum in the starting community, but were replaced by Firmicutes within three days. Seventy-eight genera were identified from the 224 OTUs, in which Bifidobacterium, Leuconostoc, Lactococcus, and Lactobacillus dominated, accounting for over 96% of the total bacterial population after three days' fermentation. UniFrac-Principal Coordinate Analysis of longitudinal fermented samples revealed dramatic changes in the bacterial community in kôso, resulting in significantly low diversity at the end of fermentation as compared with the complex starting community.

  11. Fermented beverages of pre- and proto-historic China.

    PubMed

    McGovern, Patrick E; Zhang, Juzhong; Tang, Jigen; Zhang, Zhiqing; Hall, Gretchen R; Moreau, Robert A; Nuñez, Alberto; Butrym, Eric D; Richards, Michael P; Wang, Chen-Shan; Cheng, Guangsheng; Zhao, Zhijun; Wang, Changsui

    2004-12-21

    Chemical analyses of ancient organics absorbed into pottery jars from the early Neolithic village of Jiahu in Henan province in China have revealed that a mixed fermented beverage of rice, honey, and fruit (hawthorn fruit and/or grape) was being produced as early as the seventh millennium before Christ (B.C.). This prehistoric drink paved the way for unique cereal beverages of the proto-historic second millennium B.C., remarkably preserved as liquids inside sealed bronze vessels of the Shang and Western Zhou Dynasties. These findings provide direct evidence for fermented beverages in ancient Chinese culture, which were of considerable social, religious, and medical significance, and help elucidate their earliest descriptions in the Shang Dynasty oracle inscriptions.

  12. Fermented beverages of pre- and proto-historic China

    PubMed Central

    McGovern, Patrick E.; Zhang, Juzhong; Tang, Jigen; Zhang, Zhiqing; Hall, Gretchen R.; Moreau, Robert A.; Nuñez, Alberto; Butrym, Eric D.; Richards, Michael P.; Wang, Chen-shan; Cheng, Guangsheng; Zhao, Zhijun; Wang, Changsui

    2004-01-01

    Chemical analyses of ancient organics absorbed into pottery jars from the early Neolithic village of Jiahu in Henan province in China have revealed that a mixed fermented beverage of rice, honey, and fruit (hawthorn fruit and/or grape) was being produced as early as the seventh millennium before Christ (B.C.). This prehistoric drink paved the way for unique cereal beverages of the proto-historic second millennium B.C., remarkably preserved as liquids inside sealed bronze vessels of the Shang and Western Zhou Dynasties. These findings provide direct evidence for fermented beverages in ancient Chinese culture, which were of considerable social, religious, and medical significance, and help elucidate their earliest descriptions in the Shang Dynasty oracle inscriptions. PMID:15590771

  13. 78 FR 22918 - Early Career Doctorates Survey; Extension of Public Comment Period; Correction

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-04-17

    ... NATIONAL SCIENCE FOUNDATION Early Career Doctorates Survey; Extension of Public Comment Period; Correction AGENCY: National Science Foundation. ACTION: Notification of extension of public comment period..., seeking comments on establishing the Early Career Doctorates Survey. The document contained an incorrect...

  14. Low-Carbon Fuel and Chemical Production by Anaerobic Gas Fermentation.

    PubMed

    Daniell, James; Nagaraju, Shilpa; Burton, Freya; Köpke, Michael; Simpson, Séan Dennis

    World energy demand is expected to increase by up to 40% by 2035. Over this period, the global population is also expected to increase by a billion people. A challenge facing the global community is not only to increase the supply of fuel, but also to minimize fossil carbon emissions to safeguard the environment, at the same time as ensuring that food production and supply is not detrimentally impacted. Gas fermentation is a rapidly maturing technology which allows low carbon fuel and commodity chemical synthesis. Unlike traditional biofuel technologies, gas fermentation avoids the use of sugars, relying instead on gas streams rich in carbon monoxide and/or hydrogen and carbon dioxide as sources of carbon and energy for product synthesis by specialized bacteria collectively known as acetogens. Thus, gas fermentation enables access to a diverse array of novel, large volume, and globally available feedstocks including industrial waste gases and syngas produced, for example, via the gasification of municipal waste and biomass. Through the efforts of academic labs and early stage ventures, process scale-up challenges have been surmounted through the development of specialized bioreactors. Furthermore, tools for the genetic improvement of the acetogenic bacteria have been reported, paving the way for the production of a spectrum of ever-more valuable products via this process. As a result of these developments, interest in gas fermentation among both researchers and legislators has grown significantly in the past 5 years to the point that this approach is now considered amongst the mainstream of emerging technology solutions for near-term low-carbon fuel and chemical synthesis.

  15. Lysine Fermentation: History and Genome Breeding.

    PubMed

    Ikeda, Masato

    Lysine fermentation by Corynebacterium glutamicum was developed in 1958 by Kyowa Hakko Kogyo Co. Ltd. (current Kyowa Hakko Bio Co. Ltd.) and is the second oldest amino acid fermentation process after glutamate fermentation. The fundamental mechanism of lysine production, discovered in the early stages of the process's history, gave birth to the concept known as "metabolic regulatory fermentation," which is now widely applied to metabolite production. After the development of rational metabolic engineering, research on lysine production first highlighted the need for engineering of the central metabolism from the viewpoints of precursor supply and NADPH regeneration. Furthermore, the existence of active export systems for amino acids was first demonstrated for lysine in C. glutamicum, and this discovery has resulted in the current recognition of such exporters as an important consideration in metabolite production. Lysine fermentation is also notable as the first process to which genomics was successfully applied to improve amino acid production. The first global "genome breeding" strategy was developed using a lysine producer as a model; this has since led to new lysine producers that are more efficient than classical industrial producers. These advances in strain development technology, combined with recent systems-level approaches, have almost achieved the optimization of entire cellular systems as cell factories for lysine production. In parallel, the continuous improvement of the process has resulted not only in fermentation processes with reduced load on downstream processing but also in commercialization of various product forms according to their intended uses. Nowadays lysine fermentation underpins a giant lysine demand of more than 2 million metric tons per year.

  16. [Enhanced ε-poly-L-lysine production by improving cellular activity during fermentation].

    PubMed

    Liu, Shengrong; Wu, Qingping; Zhang, Jumei; Yang, Xiaojuan; Cai, Shuzhen

    2015-06-04

    To assess the effect of cellular activity on ε-poly-1-lysine (ε-PL) biosynthesis and thereby to rationally improve the production, we studied the cellular activity, ε-PL formation and other parameters cross flask fermentation by Streptomyces ahygroscopicus. Laser scanning confocal microscopy and a colorimetric method were used to determine cellular activity using BacLight Live/Dead and 5-cyano-2,3-ditolyl tetrazolium chloride (CTC) as viable stains. To enhance the activity of the cells in the ε-PL production period, yeast extract was added. During ε-PL submerged fermentation in flasks, most cells were active in the growth period (0 - 16 h); cells had metabolic activity in the growth and earlier ε-PL production periods between 0 and 30 h fermentation. Almost no activity was detected after 48 h fermentation when no ε-PL was produced. The improved fermentation achieved 2. 24 g/L ε-PL from 1.04 g/L. Biosynthesis of ε-PL can be boosted by up-regulating cell activity in its production phase.

  17. Culture-independent quantification of physiologically-active microbial groups in fermented foods using rRNA-targeted oligonucleotide probes: application to pozol, a Mexican lactic acid fermented maize dough.

    PubMed

    Ampe, F; ben Omar, N; Guyot, J P

    1999-07-01

    Nine phylogenetic oligonucleotide probes were used to describe at the genus level the microbial community responsible for the spontaneous fermentation of maize, leading to the production of Mexican pozol. Ribosomal RNAs of specific groups and genera, in particular, lactic acid bacteria, were quantified using a culture-independent approach. In the early stage of the fermentation, Lactococcus and Leuconostoc appeared to be the dominant genera. A contrario, these represented minor genera at the end of the fermentation when Lactobacillus dominated the process. In addition, eukaryotes seemed to play a significant role throughout the fermentation and enterobacteria could be detected by this method.

  18. Genome-wide Fitness Profiles Reveal a Requirement for Autophagy During Yeast Fermentation

    PubMed Central

    Piggott, Nina; Cook, Michael A.; Tyers, Mike; Measday, Vivien

    2011-01-01

    The ability of cells to respond to environmental changes and adapt their metabolism enables cell survival under stressful conditions. The budding yeast Saccharomyces cerevisiae (S. cerevisiae) is particularly well adapted to the harsh conditions of anaerobic wine fermentation. However, S. cerevisiae gene function has not been previously systematically interrogated under conditions of industrial fermentation. We performed a genome-wide study of essential and nonessential S. cerevisiae gene requirements during grape juice fermentation to identify deletion strains that are either depleted or enriched within the viable fermentative population. Genes that function in autophagy and ubiquitin-proteasome degradation are required for optimal survival during fermentation, whereas genes that function in ribosome assembly and peroxisome biogenesis impair fitness during fermentation. We also uncover fermentation phenotypes for 139 uncharacterized genes with no previously known cellular function. We demonstrate that autophagy is induced early in wine fermentation in a nitrogen-replete environment, suggesting that autophagy may be triggered by other forms of stress that arise during fermentation. These results provide insights into the complex fermentation process and suggest possible means for improvement of industrial fermentation strains. PMID:22384346

  19. Influence of trace elements mixture on bacterial diversity and fermentation characteristics of liquid diet fermented with probiotics under air-tight condition.

    PubMed

    He, Yuyong; Chen, Zhiyu; Liu, Xiaolan; Wang, Chengwei; Lu, Wei

    2014-01-01

    Cu2+, Zn2+, Fe2+ and I- are often supplemented to the diet of suckling and early weaning piglets, but little information is available regarding the effects of different Cu2+, Zn2+, Fe2+ and I- mixtures on bacteria growth, diversity and fermentation characteristics of fermented liquid diet for piglets. Pyrosequencing was performed to investigate the effect of Cu2+, Zn2+, Fe2+ and I- mixtures on the diversity, growth and fermentation characteristics of bacteria in the liquid diet fermented with Bacillus subtilis and Enterococcus faecalis under air-tight condition. Results showed that the mixtures of Cu2+, Zn2+, Fe2+ and I- at different concentrations promoted Bacillus growth, increased bacterial diversity and lactic acid production and lowered pH to about 5. The importance of Cu2+, Zn2+, Fe2+ and I- is different for Bacillus growth with the order Zn2+> Fe2+>Cu2+> I- in a 21-d fermentation and Cu2+>I->Fe2+>Zn2+ in a 42-d fermentation. Cu2+, Zn2+, Fe2+ and I- is recommended at a level of 150, 60, 150 and 0.6 mg/kg respectively for the production of fermented liquid diet with Bacillus subtilis. The findings improve our understanding of the influence of trace elements on liquid diet fermentation with probiotics and support the proper use of trace elements in the production of fermented liquid diet for piglets.

  20. Effect of fermented moist feed on performance, gut bacteria and gut histo-morphology in broilers.

    PubMed

    Missotten, J A; Michiels, J; Dierick, N; Ovyn, A; Akbarian, A; De Smet, S

    2013-01-01

    1. Fermented feed has been shown to be beneficial in pig nutrition as a tool to reduce gut microbial disorders. Experiments with fermented feed in poultry are scarce, probably because of the belief that wet feed is less suitable for this species and causes wet litter. 2. A total of 280 one-d-old Ross 308 chickens were used in a completely randomised design with two dietary treatments (7 replicates of 20 birds/treatment); air-dry feed versus the same feed in moist form (water:feed ratio of 1.3:1, on a weight basis), inoculated with Lactobacillus plantarum NCIMB 40087 (9 log10 CFU/kg feed) and batch-fermented for 48 h at 26°C. The birds were given starter (d 0-13), grower (d 4-26) and finisher (d 27-39) diets ad libitum. At the end of the grower and finisher period, two birds per pen were removed to sample intestinal contents for cultivating bacteria and intestinal tissue to determine villus height and crypt depth. 3. Fermented moist feed (FMF) batches showed good characteristics, with a pH between 3.9 and 4.4 and DL-lactic acid between 137 and 286 mmol/l. Daily feed intake and gain were reduced considerably in the FMF group in the starter (-40 and -44%, respectively) and grower (-23 and -16%) period, though in the finisher period these birds performed better, with an improved feed utilisation. Concomitant with the latter, villus height at the mid-jejunum and mid-ileum on d 39 was higher (+22.6% and +16.0%). Significantly more Lactobacilli and less coliforms were found in the foregut and less Streptococci in ileum and caeca of birds given FMF. 4. This trial showed that FMF was detrimental for early bird growth but affected beneficially feed efficiency, the composition of the gut bacteria and villus height in the small intestine in the finisher period in broilers.

  1. Changes in free-radical scavenging ability of kombucha tea during fermentation.

    PubMed

    Jayabalan, R; Subathradevi, P; Marimuthu, S; Sathishkumar, M; Swaminathan, K

    2008-07-01

    Kombucha tea is a fermented tea beverage produced by fermenting sugared black tea with tea fungus (kombucha). Free-radical scavenging abilities of kombucha tea prepared from green tea (GTK), black tea (BTK) and tea waste material (TWK) along with pH, phenolic compounds and reducing power were investigated during fermentation period. Phenolic compounds, scavenging activity on DPPH radical, superoxide radical (xanthine-xanthine oxidase system) and inhibitory activity against hydroxyl radical mediated linoleic acid oxidation (ammonium thiocyanate assay) were increased during fermentation period, whereas pH, reducing power, hydroxyl radical scavenging ability (ascorbic acid-iron EDTA) and anti-lipid peroxidation ability (thiobarbituric assay) were decreased. From the present study, it is obvious that there might be some chances of structural modification of components in tea due to enzymes liberated by bacteria and yeast during kombucha fermentation which results in better scavenging performance on nitrogen and superoxide radicals, and poor scavenging performance on hydroxyl radicals. Copyright © 2007 Elsevier Ltd. All rights reserved.

  2. Recent advances in microbial fermentation for dairy and health

    PubMed Central

    Arendt, Elke; Hill, Colin; Stanton, Catherine; Ross, R Paul

    2017-01-01

    Microbial fermentation has been used historically for the preservation of foods, the health benefits of which have since come to light. Early dairy fermentations depended on the spontaneous activity of the indigenous microbiota of the milk. Modern fermentations rely on defined starter cultures with desirable characteristics to ensure consistency and commercial viability. The selection of defined starters depends on specific phenotypes that benefit the product by guaranteeing shelf life and ensuring safety, texture, and flavour. Lactic acid bacteria can produce a number of bioactive metabolites during fermentation, such as bacteriocins, biogenic amines, exopolysaccharides, and proteolytically released peptides, among others. Prebiotics are added to food fermentations to improve the performance of probiotics. It has also been found that prebiotics fermented in the gut can have benefits that go beyond helping probiotic growth. Studies are now looking at how the fermentation of prebiotics such as fructo-oligosaccharides can help in the prevention of diseases such as osteoporosis, obesity, and colorectal cancer. The potential to prevent or even treat disease through the fermentation of food is a medically and commercially attractive goal and is showing increasing promise. However, the stringent regulation of probiotics is beginning to detrimentally affect the field and limit their application. PMID:28649371

  3. Indigenous Bacteria and Fungi Drive Traditional Kimoto Sake Fermentations

    PubMed Central

    Bokulich, Nicholas A.; Ohta, Moe; Lee, Morgan

    2014-01-01

    Sake (Japanese rice wine) production is a complex, multistage process in which fermentation is performed by a succession of mixed fungi and bacteria. This study employed high-throughput rRNA marker gene sequencing, quantitative PCR, and terminal restriction fragment length polymorphism to characterize the bacterial and fungal communities of spontaneous sake production from koji to product as well as brewery equipment surfaces. Results demonstrate a dynamic microbial succession, with koji and early moto fermentations dominated by Bacillus, Staphylococcus, and Aspergillus flavus var. oryzae, succeeded by Lactobacillus spp. and Saccharomyces cerevisiae later in the fermentations. The microbiota driving these fermentations were also prevalent in the production environment, illustrating the reservoirs and routes for microbial contact in this traditional food fermentation. Interrogating the microbial consortia of production environments in parallel with food products is a valuable approach for understanding the complete ecology of food production systems and can be applied to any food system, leading to enlightened perspectives for process control and food safety. PMID:24973064

  4. Oral intake of Lactobacillus helveticus-fermented milk whey decreased transepidermal water loss and prevented the onset of sodium dodecylsulfate-induced dermatitis in mice.

    PubMed

    Baba, Hidehiko; Masuyama, Akihiro; Yoshimura, Chiaki; Aoyama, Yoshiko; Takano, Toshiaki; Ohki, Kohji

    2010-01-01

    We investigated the effects of oral intake of Lactobacillus helveticus-fermented milk whey on the intact and sodium dodecylsulfate (SDS)-exposed skin of Hos:HR-1 hairless mice. The mice were allowed to drink 10% L. helveticus-fermented milk whey in distilled water ad libitum for 5 weeks. SDS solution was topically applied to the dorsal skin at 4 weeks, leading to the development of dermatitis. The skin moisture content, transepidermal water loss, and sizes of the dermatitis areas were periodically measured. Compared with oral intake of water alone, oral intake of water containing L. helveticus-fermented milk whey for 4 weeks significantly lowered transepidermal water loss from intact skin, significantly reduced in size the areas of early SDS-induced dermatitis, and ameliorated both the SDS-induced decrease in moisture content and the increase in transepidermal water loss. These results suggest that oral intake of L. helveticus-fermented milk whey might be effective in promoting the epidermal barrier function and in preventing the onset of dermatitis.

  5. Impact of assimilable nitrogen availability in glucose uptake kinetics in Saccharomyces cerevisiae during alcoholic fermentation

    PubMed Central

    2012-01-01

    Background The expression and activity of the different Saccharomyces cerevisiae hexose uptake systems (Hxt) and the kinetics of glucose uptake are considered essential to industrial alcoholic fermentation performance. However, the dynamics of glucose uptake kinetics during the different stages of fermentation, depending on glucose and nitrogen availability, is very poorly characterized. The objective of the present work was to examine thoroughly the alterations occurring in glucose uptake kinetics during alcoholic fermentation, by the wine strain S. cerevisiae PYCC 4072, of a synthetic grape juice basal medium with either a limiting or non-limiting initial nitrogen concentration and following nitrogen supplementation of the nitrogen-depleted sluggish fermentation. Results Independently of the initial concentration of the nitrogen source, glucose transport capacity is maximal during the early stages of fermentation and presumably sustained by the low-affinity and high-capacity glucose transporter Hxt1p. During nitrogen-limited sluggish fermentation, glucose uptake capacity was reduced to approximately 20% of its initial values (Vmax = 4.9 ± 0.8 compared to 21.9 ± 1.2 μmol h-1 10-8 cells), being presumably sustained by the low-affinity glucose transporter Hxt3p (considering the calculated Km = 39.2 ± 8.6 mM). The supplementation of the sluggish fermentation broth with ammonium led to the increase of glucose transport capacity associated to the expression of different glucose uptake systems with low and high affinities for glucose (Km = 58.2 ± 9.1 and 2.7 ± 0.4 mM). A biclustering analysis carried out using microarray data, previously obtained for this yeast strain transcriptional response to equivalent fermentation conditions, indicates that the activation of the expression of genes encoding the glucose transporters Hxt2p (during the transition period to active fermentation) and Hxt3p, Hxt4p, Hxt6p and Hxt7p (during the

  6. Effects of low-fat or full-fat fermented and non-fermented dairy foods on selected cardiovascular biomarkers in overweight adults.

    PubMed

    Nestel, Paul J; Mellett, Natalie; Pally, Suzana; Wong, Gerard; Barlow, Chris K; Croft, Kevin; Mori, Trevor A; Meikle, Peter J

    2013-12-01

    The association between consumption of full-fat dairy foods and CVD may depend partly on the nature of products and may not apply to low-fat dairy foods. Increased circulating levels of inflammatory biomarkers after consumption of dairy product-rich meals suggest an association with CVD. In the present study, we tested the effects of low-fat and full-fat dairy diets on biomarkers associated with inflammation, oxidative stress or atherogenesis and on plasma lipid classes. Within full-fat dairy diets, we also compared fermented v. non-fermented products. In a randomised cross-over study, twelve overweight/obese subjects consumed during two 3-week periods two full-fat dairy diets containing either yogurt plus cheese (fermented) or butter, cream and ice cream (non-fermented) or a low-fat milk plus yogurt diet, with the latter being consumed between and at the end of the full-fat dairy dietary periods. The concentrations of six inflammatory and two atherogenic biomarkers known to be raised in CVD were measured as well as those of plasma F2-isoprostanes and lipid classes. The concentrations of six of the eight biomarkers tended to be higher on consumption of the low-fat dairy diet than on that of the fermented dairy diet and the concentrations of two plasmalogen lipid classes reported to be associated with increased oxidisability were also higher on consumption of the low-fat dairy diet than on that of the fermented dairy diet (P< 0.001), although plasma F2-isoprostane concentrations did not differ on consumption of any of the diets. On the other hand, the concentrations of plasma sphingomyelin and IL-6 were significantly higher on consumption of the non-fermented dairy diet than on that of the low-fat dairy diet (P< 0.02). In conclusion, short-term diets containing low-fat dairy products did not lead to a more favourable biomarker profile associated with CVD risk compared with the full-fat dairy products, suggesting that full-fat fermented dairy products may be the more

  7. Bacteriophage Ecology in a Commercial Cucumber Fermentation

    PubMed Central

    Pérez-Díaz, I. M.; Hayes, J. S.; Breidt, F.

    2012-01-01

    To reduce high-salt waste from cucumber fermentations, low-salt fermentations are under development. These fermentations may require the use of starter cultures to ensure normal fermentations. Because potential phage infection can cause starter culture failure, it is important to understand phage ecology in the fermentations. This study investigated the phage ecology in a commercial cucumber fermentation. Brine samples taken from a fermentation tank over a 90-day period were plated onto deMan-Rogosa-Sharpe agar plates. A total of 576 lactic acid bacterial isolates were randomly selected to serve as potential hosts for phage isolation. Filtered brine served as a phage source. Fifty-seven independent phage isolates were obtained, indicating that 10% of the bacterial isolates were sensitive to phage attack. Phage hosts include Lactobacillus brevis (67% of all hosts), Lactobacillus plantarum (21%), Weissella paramesenteroides, Weissella cibaria, and Pediococcus ethanolidurans. Nearly 50% of phages were isolated on day 14, and the majority of them attacked L. brevis. Some phages had a broad host range and were capable of infecting multiple hosts in two genera. Other phages were species specific or strain specific. About 30% of phage isolates produced turbid pinpoint plaques or only caused reduced cell growth on the bacterial lawns. Six phages with distinct host ranges were characterized. The data from this study showed that abundant and diverse phages were present in the commercial cucumber fermentation, which could cause significant mortality to the lactic acid bacteria population. Therefore, a phage control strategy may be needed in low-salt cucumber fermentations. PMID:23023756

  8. Sensitive periods of substance abuse: Early risk for the transition to dependence

    PubMed Central

    Jordan, Chloe J.; Andersen, Susan L.

    2016-01-01

    Early adolescent substance use dramatically increases the risk of lifelong substance use disorder (SUD). An adolescent sensitive period evolved to allow the development of risk-taking traits that aid in survival; today these may manifest as a vulnerability to drugs of abuse. Early substance use interferes with ongoing neurodevelopment to induce neurobiological changes that further augment SUD risk. Although many individuals use drugs recreationally, only a small percentage transition to SUD. Current theories on the etiology of addiction can lend insights into the risk factors that increase vulnerability from early recreational use to addiction. Building on the work of others, we suggest individual risk for SUD emerges from an immature PFC combined with hyper-reactivity of reward salience, habit, and stress systems. Early identification of risk factors is critical to reducing the occurrence of SUD. We suggest preventative interventions for SUD that can be either tailored to individual risk profiles and/or implemented broadly, prior to the sensitive adolescent period, to maximize resilience to developing substance dependence. Recommendations for future research include a focus on the juvenile and adolescent periods as well as on sex differences to better understand early risk and identify the most efficacious preventions for SUD. PMID:27840157

  9. System-level modeling of acetone-butanol-ethanol fermentation.

    PubMed

    Liao, Chen; Seo, Seung-Oh; Lu, Ting

    2016-05-01

    Acetone-butanol-ethanol (ABE) fermentation is a metabolic process of clostridia that produces bio-based solvents including butanol. It is enabled by an underlying metabolic reaction network and modulated by cellular gene regulation and environmental cues. Mathematical modeling has served as a valuable strategy to facilitate the understanding, characterization and optimization of this process. In this review, we highlight recent advances in system-level, quantitative modeling of ABE fermentation. We begin with an overview of integrative processes underlying the fermentation. Next we survey modeling efforts including early simple models, models with a systematic metabolic description, and those incorporating metabolism through simple gene regulation. Particular focus is given to a recent system-level model that integrates the metabolic reactions, gene regulation and environmental cues. We conclude by discussing the remaining challenges and future directions towards predictive understanding of ABE fermentation. © FEMS 2016. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  10. Disappearance of patulin during alcoholic fermentation of apple juice.

    PubMed

    Stinson, E E; Osman, S F; Huhtanen, C N; Bills, D D

    1978-10-01

    Eight yeast strains were used in three typical American processes to ferment apple juice containing 15 mg of added patulin per liter. Patulin was reduced to less than the minimum detectable level of 50 microgram/liter in all but two cases; in all cases, the level of patulin was reduced by over 99% during alcoholic fermentation. In unfermented samples of apple juice, the concentration of added patulin declined by only 10% when the juice was held for 2 weeks, a period equivalent to the time required for fermentation.

  11. Chromohalobacter is a Causing Agent for the Production of Organic Acids and Putrescine during Fermentation of Ganjang, a Korean Traditional Soy Sauce.

    PubMed

    Jung, Ji Young; Chun, Byung Hee; Jeon, Che Ok

    2015-12-01

    Ganjang, a Korean traditional fermented soy sauce, is prepared by soaking doenjang-meju (fermented soybeans) in approximately 20% (w/v) solar salt solution. The metabolites and bacterial communities during ganjang fermentation were simultaneously investigated to gain a better understanding of the roles of the microbial population. The bacterial community analysis based on denaturing gradient gel electrophoresis of 16S rRNA gene sequences showed that initially, the genus Cobetia was predominant (0 to 10 d), followed by Bacillus (5 to 74 d), and eventually, Chromohalobacter became predominant until the end of the fermentation process (74 to 374 d). Metabolite analysis using (1)H-NMR showed that carbon compounds, such as fructose, galactose, glucose, and glycerol, probably released from doenjang-meju, increased rapidly during the early fermentation period (0 to 42 d). After removal of doenjang-meju from the ganjang solution (42 d), the initial carbon compounds remained nearly constant without the increase of fermentation products. At this point, Bacillus species, which probably originated from doenjang-meju, were predominant, suggesting that Bacillus is not mainly responsible for ganjang fermentation. Fermentation products including acetate, lactate, α-aminobutyrate, γ-aminobutyrate, and putrescine increased quickly with the rapid decrease of the initial carbon compounds, while Chromohalobacter, probably derived from the solar salts, was predominant. Multivariate redundancy analysis indicated that the Chromohalobacter population was closely correlated with the production of the organic acids and putrescine during the ganjang fermentation. These results may suggest that Chromohalobacter is a causing agent responsible for the production of organic acids and putrescine during ganjang fermentation and that the solar salts, not doenjang-meju, is an important microbial source for ganjang fermentation. © 2015 Institute of Food Technologists®

  12. Simultaneous and successive inoculations of yeasts and lactic acid bacteria on the fermentation of an unsulfited Tannat grape must

    PubMed Central

    Muñoz, Viviana; Beccaria, Bruno; Abreo, Eduardo

    2014-01-01

    Interactions between yeasts and lactic acid bacteria are strain specific, and their outcome is expected to change in simultaneous alcoholic - malolactic fermentations from the pattern observed in successive fermentations. One Oenococcus oeni strain Lalvin VP41™ was inoculated with two Saccharomyces cerevisiae strains either simultaneously, three days after the yeast inoculation, or when alcoholic fermentation was close to finish. Early bacterial inoculations with each yeast strain allowed for the growth of the bacterial populations, and the length of malolactic fermentation was reduced to six days. Alcoholic fermentation by Lalvin ICV D80® yeast strain left the highest residual sugar, suggesting a negative effect of the bacterial growth and malolactic activity on its performance. In sequential inoculations the bacterial populations did not show actual growth with either yeast strain. In this strategy, both yeast strains finished the alcoholic fermentations, and malolactic fermentations took longer to finish. Lalvin ICV D80® allowed for higher viability and activity of the bacterial strain than Fermicru UY4® under the three inoculation strategies. This was beneficial for the sequential completion of both fermentations, but negatively affected the completion of alcoholic fermentation by Lalvin ICV D80® in the early bacteria additions. Conversely, Fermicru UY4®, which was rather inhibitory towards the bacteria, favored the timely completion of both fermentations simultaneously. As bacteria in early inoculations with low or no SO2 addition can be expected to multiply and interact with fermenting yeasts, not only are the yeast-bacterium strains combination and time point of the inoculation to be considered, but also the amount of bacteria inoculated. PMID:24948914

  13. Indigenous bacteria and fungi drive traditional kimoto sake fermentations.

    PubMed

    Bokulich, Nicholas A; Ohta, Moe; Lee, Morgan; Mills, David A

    2014-09-01

    Sake (Japanese rice wine) production is a complex, multistage process in which fermentation is performed by a succession of mixed fungi and bacteria. This study employed high-throughput rRNA marker gene sequencing, quantitative PCR, and terminal restriction fragment length polymorphism to characterize the bacterial and fungal communities of spontaneous sake production from koji to product as well as brewery equipment surfaces. Results demonstrate a dynamic microbial succession, with koji and early moto fermentations dominated by Bacillus, Staphylococcus, and Aspergillus flavus var. oryzae, succeeded by Lactobacillus spp. and Saccharomyces cerevisiae later in the fermentations. The microbiota driving these fermentations were also prevalent in the production environment, illustrating the reservoirs and routes for microbial contact in this traditional food fermentation. Interrogating the microbial consortia of production environments in parallel with food products is a valuable approach for understanding the complete ecology of food production systems and can be applied to any food system, leading to enlightened perspectives for process control and food safety. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

  14. Application of gamma irradiation for aging control and improvement of shelf-life of kimchi, korean salted and fermented vegetables

    NASA Astrophysics Data System (ADS)

    Song, Hyun-Pa; Kim, Dong-Ho; Yook, Hong-Sun; Kim, Kyung-Soo; Kwon, Joong-Ho; Byun, Myung-Woo

    2004-09-01

    This study was carried out to evaluate the application of food irradiation as a method for extending shelf life of Kimchi. Gamma irradiation up to 10 kGy in the early stage of Kimchi fermentation had a dose-dependent effect on the inactivation of fermentative microbes, lowering the lactate dehydrogenase (LDH) activity and delaying acidification. Although gamma irradiation on the mid-fermentation stage of Kimchi inactivated the fermentative microbes effectively, LDH activity remained high and acidification continued. Kimchi irradiated at 10 kGy had lower scores in acceptability than those of control, 2.5 and 5 kGy irradiated. Therefore, gamma irradiation upto 5 kGy in the early fermentation stage is recommended for aging control and the improvement of shelf life of Kimchi.

  15. Selection of functional lactic acid bacteria as starter cultures for the fermentation of Korean leek (Allium tuberosum Rottler ex Sprengel.).

    PubMed

    Yang, Jaesik; Ji, Yosep; Park, Hyunjoon; Lee, Jieun; Park, Soyoung; Yeo, Soyoung; Shin, Hyunkil; Holzapfel, Wilhelm H

    2014-11-17

    The purpose of this research was to find safe and suitable starter cultures for the fermentation of Korean leek (Allium tuberosum Rottler), also known as garlic chives or Oriental garlic. This traditional herb has several functional properties and a strong flavour; its leaves are used as food material. Eighteen strains of lactic acid bacteria (LAB) were isolated from well-fermented leek kimchi. Controlled fermentation of the leek leaves was conducted with 2 strains (Weissella confusa LK4 and Lactobacillus plantarum LK8), selected as potential starter cultures on the basis of their safety properties, and on the pH, total titratable acidity (TTA), and viable cell numbers [colony forming units (CFUml(-1))] achieved during the fermentation. Microbial dynamics was also followed during fermentation by using PCR-DGGE (Denaturing Gradient Gel Electrophoresis) on DNA level. To analyse bioactive compounds such as thiols and allicin (diallyl thiosulfinates), the total flavonoid and polyphenolic contents were determined by colorimetric methods. Functional properties were assessed on the basis of anti-oxidative capacities by determining the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical-scavenging effect, and ferric reducing antioxidant power (FRAP). W. confusa LK4 rapidly increased during the first stage of leek fermentation, and was mainly responsible for accelerated fermentation during the early period in contrast to L. plantarum LK8, a stronger acid producer during the later stages of fermentation. After 48 h fermentation, leeks fermented with W. confusa LK4 showed the highest radical scavenging effects and reducing ability. The detectable amount of allicin of fermented leeks decreased relative to the change in pH, whereas the concentration of thiols significantly increased. Total flavonoid and poly-phenolic contents changed during fermentation and showed correlation with anti-oxidant effects. We therefore suggest the suitability of W. confusa LK4 as a potential starter

  16. Microbial succession and the functional potential during the fermentation of Chinese soy sauce brine

    PubMed Central

    Sulaiman, Joanita; Gan, Han Ming; Yin, Wai-Fong; Chan, Kok-Gan

    2014-01-01

    The quality of traditional Chinese soy sauce is determined by microbial communities and their inter-related metabolic roles in the fermentation tank. In this study, traditional Chinese soy sauce brine samples were obtained periodically to monitor the transitions of the microbial population and functional properties during the 6 months of fermentation process. Whole genome shotgun method revealed that the fermentation brine was dominated by the bacterial genus Weissella and later dominated by the fungal genus Candida. Metabolic reconstruction of the metagenome sequences demonstrated a characteristic profile of heterotrophic fermentation of proteins and carbohydrates. This was supported by the detection of ethanol with stable decrease of pH values. To the best of our knowledge, this is the first study that explores the temporal changes in microbial successions over a period of 6 months, through metagenome shotgun sequencing in traditional Chinese soy sauce fermentation and the biological processes therein. PMID:25400624

  17. Microbial succession and the functional potential during the fermentation of Chinese soy sauce brine.

    PubMed

    Sulaiman, Joanita; Gan, Han Ming; Yin, Wai-Fong; Chan, Kok-Gan

    2014-01-01

    The quality of traditional Chinese soy sauce is determined by microbial communities and their inter-related metabolic roles in the fermentation tank. In this study, traditional Chinese soy sauce brine samples were obtained periodically to monitor the transitions of the microbial population and functional properties during the 6 months of fermentation process. Whole genome shotgun method revealed that the fermentation brine was dominated by the bacterial genus Weissella and later dominated by the fungal genus Candida. Metabolic reconstruction of the metagenome sequences demonstrated a characteristic profile of heterotrophic fermentation of proteins and carbohydrates. This was supported by the detection of ethanol with stable decrease of pH values. To the best of our knowledge, this is the first study that explores the temporal changes in microbial successions over a period of 6 months, through metagenome shotgun sequencing in traditional Chinese soy sauce fermentation and the biological processes therein.

  18. Insights from Australian parents into educational experiences in the early postnatal period.

    PubMed

    McKellar, Lois V; Pincombe, Jan I; Henderson, Ann M

    2006-12-01

    to investigate the provision of parent education during the early postnatal period in order to gain insight that, through stakeholder collaboration, will contribute to the development of innovative strategies to enhance the provision of postnatal education in a contemporary health-care environment. the study comprises the first stage of an action-research project. The first stage of research sought to explore the experiences of mothers and fathers in the early postnatal period by conducting a questionnaire within 4 weeks of the birth of their baby. The data obtained from the questionnaire is to inform an action-research group for stage two of the project. The Children, Youth and Women's Health Service, a large city maternity hospital in South Australia, covering a range of socio-economic strata. 85 parents completed and returned the questionnaire, comprising 52 mothers and 33 fathers. an anonymous self-report questionnaire was purpose designed to provide each parent with an opportunity to reflect on their own experience, with particular emphasis given to the provision of education and support during the early postnatal period. a number of themes emerged, including a window of opportunity during the postnatal hospital stay to provide education and support, despite the reduction in the length of stay; the need for a family-centred approach to maternity services; and the significance of self and social network in the early transition to parenthood. The findings from this stage of the research, combined with a review of the literature, provide insight that will contribute to stage two of the study. At this stage, an action-research group will continue planning to develop specific actions to enhance the provision of education to parents in the early postnatal period. These actions will subsequently be implemented and assessed.

  19. Effects of Fermented Dairy Products on Skin: A Systematic Review.

    PubMed

    Vaughn, Alexandra R; Sivamani, Raja K

    2015-07-01

    Fermented dairy products, such as yogurt, have been proposed as a natural source of probiotics to promote intestinal health. Growing evidence shows that modulation of the gastrointestinal tract microbiota can modulate skin disease as well. This systematic review was conducted to examine the evidence for the use of ingested fermented dairy products to modulate skin health and function. We also sought to review the effects of the topical application of dairy products. The PubMed and Embase databases were systematically searched for clinical studies involving humans only that examined the relationship between fermented dairy products and skin health. A total of 312 articles were found and a total of 4 studies met inclusion criteria. Three studies evaluated the effects of ingestion, while one evaluated the effects of topical application. All studies noted improvement with the use of fermented dairy. Overall, there is early and limited evidence that fermented dairy products, used both topically and orally, may provide benefits for skin health. However, existing studies are limited and further studies will be important to better assess efficacy and the mechanisms involved.

  20. Electro-Fermentation - Merging Electrochemistry with Fermentation in Industrial Applications.

    PubMed

    Schievano, Andrea; Pepé Sciarria, Tommy; Vanbroekhoven, Karolien; De Wever, Heleen; Puig, Sebastià; Andersen, Stephen J; Rabaey, Korneel; Pant, Deepak

    2016-11-01

    Electro-fermentation (EF) merges traditional industrial fermentation with electrochemistry. An imposed electrical field influences the fermentation environment and microbial metabolism in either a reductive or oxidative manner. The benefit of this approach is to produce target biochemicals with improved selectivity, increase carbon efficiency, limit the use of additives for redox balance or pH control, enhance microbial growth, or in some cases enhance product recovery. We discuss the principles of electrically driven fermentations and how EF can be used to steer both pure culture and microbiota-based fermentations. An overview is given on which advantages EF may bring to both existing and innovative industrial fermentation processes, and which doors might be opened in waste biomass utilization towards added-value biorefineries. Copyright © 2016 Elsevier Ltd. All rights reserved.

  1. Mutagenizing brewing yeast strain for improving fermentation property of beer.

    PubMed

    Liu, Zengran; Zhang, Guangyi; Sun, Yunping

    2008-07-01

    A brewing yeast mutant with perfect sugar fermentation capacity was isolated by mutagenizing the Saccharomyces pastorianus transformant, which carries an integrated glucoamylase gene and has one copy of non-functional alpha-acetolactate synthase gene. The mutant was able to utilize maltotriose efficiently, and the maltotriose fermentability in YNB-2% maltotriose medium increased from 32.4% to 72.0% after 5 d in shaking culture. The wort fermentation test confirmed that the sugar fermentation property of the mutant was greatly improved, while its brewing performances were analogous to that of the wild-type strain and the characteristic trait of shortened beer maturation period was retained. Therefore, we believe that the brewing yeast mutant would benefit the beer industry and would be useful for low caloric beer production.

  2. Inoculated fermentation of green olives with potential probiotic Lactobacillus pentosus and Lactobacillus plantarum starter cultures isolated from industrially fermented olives.

    PubMed

    Blana, Vasiliki A; Grounta, Athena; Tassou, Chrysoula C; Nychas, George-John E; Panagou, Efstathios Z

    2014-04-01

    The performance of two strains of lactic acid bacteria (LAB), namely Lactobacillus pentosus B281 and Lactobacillus plantarum B282, previously isolated from industrially fermented table olives and screened in vitro for probiotic potential, was investigated as starter cultures in Spanish style fermentation of cv. Halkidiki green olives. Fermentation was undertaken at room temperature in two different initial salt concentrations (8% and 10%, w/v, NaCl) in the brines. The strains were inoculated as single and combined cultures and the dynamics of their population on the surface of olives was monitored for a period of 114 days. The survival of inoculated strains on olives was determined using Pulsed Field Gel Electrophoresis (PFGE). Both probiotic strains successfully colonized the olive surface at populations ranged from 6.0 to 7.0 log CFU/g throughout fermentation. PFGE analysis revealed that L. pentosus B281 presented higher colonization in both salt levels at the end of fermentation (81.2% and 93.3% in 8% and 10% NaCl brines, respectively). For L. plantarum B282 a high survival rate (83.3%) was observed in 8% NaCl brines, but in 10% NaCl the strain could not colonize the surface of olives. L. pentosus B281 also dominated over L. plantarum B282 in inoculated fermentations when the two strains were used as combined culture. The biochemical profile (pH, organic acids, volatile compounds) attained during fermentation and the sensory analysis of the final product indicated a typical lactic acid fermentation process of green olives. Copyright © 2013 Elsevier Ltd. All rights reserved.

  3. Transcriptional response of Saccharomyces cerevisiae to low temperature during wine fermentation.

    PubMed

    Deed, Rebecca C; Deed, Nathan K; Gardner, Richard C

    2015-04-01

    Although the yeast response to low temperature has industrial significance for baking, lager brewing and white wine fermentation, the molecular response of yeast cells to low temperature remains poorly characterised. Transcriptional changes were quantified in a commercial wine yeast, Enoferm M2, fermented at optimal (25 °C) and low temperature (12.5 °C), at two time points during fermentation of Sauvignon blanc grape juice. The transition from early to mid-late fermentation was notably less severe in the cold than at 25 °C, and the Rim15p-Gis1p pathway was involved in effecting this transition. Genes for three key nutrients were strongly influenced by low temperature fermentation: nitrogen, sulfur and iron/copper, along with changes in the cell wall and stress response. Transcriptional analyses during wine fermentation at 12.5 °C in four F1 hybrids of M2 also highlighted the importance of genes involved in nutrient utilisation and the stress response. We identified transcription factors that may be important for these differences between genetic backgrounds. Since low fermentation temperatures cause fundamental changes in membrane kinetics and cellular metabolism, an understanding of the physiological and genetic limitations on cellular performance will assist breeding of improved industrial strains.

  4. Metabolomic Profiles of Aspergillus oryzae and Bacillus amyloliquefaciens During Rice Koji Fermentation.

    PubMed

    Lee, Da Eun; Lee, Sunmin; Jang, Eun Seok; Shin, Hye Won; Moon, Byoung Seok; Lee, Choong Hwan

    2016-06-14

    Rice koji, used early in the manufacturing process for many fermented foods, produces diverse metabolites and enzymes during fermentation. Using gas chromatography time-of-flight mass spectrometry (GC-TOF-MS), ultrahigh-performance liquid chromatography linear trap quadrupole ion trap tandem mass spectrometry (UHPLC-LTQ-IT-MS/MS), and multivariate analysis we generated the metabolite profiles of rice koji produced by fermentation with Aspergillus oryzae (RK_AO) or Bacillus amyloliquefaciens (RK_BA) for different durations. Two principal components of the metabolomic data distinguished the rice koji samples according to their fermenter species and fermentation time. Several enzymes secreted by the fermenter species, including α-amylase, protease, and β-glucosidase, were assayed to identify differences in expression levels. This approach revealed that carbohydrate metabolism, serine-derived amino acids, and fatty acids were associated with rice koji fermentation by A. oryzae, whereas aromatic and branched chain amino acids, flavonoids, and lysophospholipids were more typical in rice koji fermentation by B. amyloliquefaciens. Antioxidant activity was significantly higher for RK_BA than for RK_AO, as were the abundances of flavonoids, including tricin, tricin glycosides, apigenin glycosides, and chrysoeriol glycosides. In summary, we have used MS-based metabolomics and enzyme activity assays to evaluate the effects of using different microbial species and fermentation times on the nutritional profile of rice koji.

  5. [Hospitals and other philanthropic foundations in early Byzantine period].

    PubMed

    Yildirim, R Vedat; Ataç, Adnan

    Early Byzantine Period includes between A.D. 330 when Constantinople was established and A.D. 518 when Justinus I became emperor. In this time period, a lot of philanthropic foundations such as hospitals, hospices, orphanages, rest homes and soup kitchens are established. Many of patriarchs and religious men opened them. In some of them, it refers to there was patients' care. The oldest hospital in Constantinople was established by Hasios Marcianos, and was next to Saint Irene Church. In addition to this Empress Flacilla wife of Theodosius the Great made hospitals restored and visited patients regularly. Hospitals were not limited in the center of Empire. Hospitals and other philanthropic foundations were established in Antiochia, Alexandria, Nikea, Adrianopolis, Castoria and Jerusalem. The concept of the modern hospital (the actual care, 'hospitality' and treatment of visitors) for the civilian masses in Europe didn't come to fruition until post Constantine and the rise of Christianity. While these early Christian hospitals were grossly over their heads regarding medical capability (they essentially served as last stops for the dying or quarantine centers), the concept of providing care to the public was the actual intent. In this regard, the first civilian hospitals were developed.

  6. Commercial Scale Cucumber Fermentations Brined with Calcium Chloride Instead of Sodium Chloride.

    PubMed

    Pérez-Díaz, I M; McFeeters, R F; Moeller, L; Johanningsmeier, S D; Hayes, J; Fornea, D S; Rosenberg, L; Gilbert, C; Custis, N; Beene, K; Bass, D

    2015-12-01

    Development of low salt cucumber fermentation processes present opportunities to reduce the amount of sodium chloride (NaCl) that reaches fresh water streams from industrial activities. The objective of this research was to translate cucumber fermentation brined with calcium chloride (CaCl2 ) instead of NaCl to commercial scale production. Although CaCl2 brined cucumber fermentations were stable in laboratory experiments, commercial scale trials using 6440 L open-top tanks rapidly underwent secondary cucumber fermentation. It was understood that a limited air purging routine, use of a starter culture and addition of preservatives to the cover brine aids in achieving the desired complete cucumber fermentation. The modified process was used for subsequent commercial trials using 12490 and 28400 L open-top tanks packed with variable size cucumbers and from multiple lots, and cover brines containing CaCl2 and potassium sorbate to equilibrated concentrations of 100 and 6 mM, respectively. Lactobacillus plantarum LA0045 was inoculated to 10(6) CFU/mL, and air purging was applied for two 2-3 h periods per day for the first 10 d of fermentation and one 2-3 h period per day between days 11 and 14. All fermentations were completed, as evidenced by the full conversion of sugars to lactic acid, decrease in pH to 3.0, and presented microbiological stability for a minimum of 21 d. This CaCl2 process may be used to produce fermented cucumbers intended to be stored short term in a manner that reduces pollution and waste removal costs. Published 2015. This article is a U.S. Government work and is in the public domain in the USA.

  7. Regulation mechanisms in mixed and pure culture microbial fermentation.

    PubMed

    Hoelzle, Robert D; Virdis, Bernardino; Batstone, Damien J

    2014-11-01

    Mixed-culture fermentation is a key central process to enable next generation biofuels and biocommodity production due to economic and process advantages over application of pure cultures. However, a key limitation to the application of mixed-culture fermentation is predicting culture product response, related to metabolic regulation mechanisms. This is also a limitation in pure culture bacterial fermentation. This review evaluates recent literature in both pure and mixed culture studies with a focus on understanding how regulation and signaling mechanisms interact with metabolic routes and activity. In particular, we focus on how microorganisms balance electron sinking while maximizing catabolic energy generation. Analysis of these mechanisms and their effect on metabolism dynamics is absent in current models of mixed-culture fermentation. This limits process prediction and control, which in turn limits industrial application of mixed-culture fermentation. A key mechanism appears to be the role of internal electron mediating cofactors, and related regulatory signaling. This may determine direction of electrons towards either hydrogen or reduced organics as end-products and may form the basis for future mechanistic models. © 2014 Wiley Periodicals, Inc.

  8. Study on the Removal of Cadmium in Rice Using Microbial Fermentation Method.

    PubMed

    Zhang, Ling; Lei, Qunying; Cheng, Yuliang; Xie, Yunfei; Qian, He; Guo, Yahui; Chen, Yi; Yao, Weirong

    2017-06-01

    This work mainly examined how to remove cadmium in rice by fermentation, the removal mechanisms, and the quality of fermented rice in order to utilize cadmium-contaminated rice. The fermentation time, temperature, liquid ratio, inoculant levels, and number of washes were varied to optimize the efficiency of cadmium removal. The optimum fermentation process, in which the rate of cadmium removal from the rice is 80.84%, required an inoculant amount of 0.1%, a liquid ratio of 1:1, a period of 60 h at 37 °C, and subsequently washed with water 4 times. The physicochemical properties of raw cadmium-contaminated rice and fermented rice were studied. Results showed that the pasting temperature of the fermented rice became lower, and temperature at which pasting starts dropped but the endothermic enthalpy increased, implying that the protein content in the rice decreased during the fermentation. It suggested that the crystal structure of rice starch changed and fermentation did not result in the formation of new chemical bonds or functional groups in the rice. Microbial fermentation method can therefore effectively reduce cadmium level in contaminated rice. © 2017 Institute of Food Technologists®.

  9. Effects of forage ensiling and ration fermentation on total mixed ration pH, ruminal fermentation and performance of growing Holstein-Zebu cross steers.

    PubMed

    Meenongyai, Watcharawit; Pattarajinda, Virote; Stelzleni, Alexander M; Sethakul, Jutarat; Duangjinda, Monchai

    2017-09-01

    Our objective was to determine the effect of forage ensiling and ration fermentation on total mixed ration pH, ruminal fermentation and animal performance. Thirty Holstein-Zebu cross steers were allotted to feeding treatments for 188 days in a randomized complete block design including: fresh grass-total mixed ration (GTMR; pH 4.7), grass silage-TMR (STMR; pH 4.0) and fermented-TMR (FTMR; pH 3.5). Average daily gain for STMR was greatest during the first 3 months period; however, that for FTMR tended to be greater than GTMR during the second 3 months period (P < 0.10). During the second period dry matter intake for STMR was the greatest (P < 0.01), but feed conversion ratio (P < 0.01) and cost per gain (P < 0.01) were the least for FTMR. Protein digestibility tended (P < 0.10) to be greater for FTMR than STMR and fat digestibility was greater (P < 0.05) for GTMR and FTMR than STMR. FTMR had less (P < 0.01) ruminal NH 3 -N content than STMR. Total volatile fatty acids post-feeding was greatest for GTMR (P < 0.01). Ruminal proportions of acetic and butyric acids were greater for FTMR than GTMR (P < 0.05); in contrast, propionic acid was greater for GTMR (P < 0.05). Utilizing silage or total ration fermentation did not negatively impact on ruminal pH. STMR and FTMRs can be used to maintain performance of growing crossbred Holstein steers. © 2017 Japanese Society of Animal Science.

  10. Analysis of microbial diversity in Shenqu with different fermentation times by PCR-DGGE.

    PubMed

    Liu, Tengfei; Jia, Tianzhu; Chen, Jiangning; Liu, Xiaoyu; Zhao, Minjie; Liu, Pengpeng

    Shenqu is a fermented product that is widely used in traditional Chinese medicine (TCM) to treat indigestion; however, the microbial strains in the fermentation process are still unknown. The aim of this study was to investigate microbial diversity in Shenqu using different fermentation time periods. DGGE (polymerase chain reaction-denaturing gradient gel electrophoresis) profiles indicated that a strain of Pediococcus acidilactici (band 9) is the predominant bacteria during fermentation and that the predominant fungi were uncultured Rhizopus, Aspergillus oryzae, and Rhizopus oryzae. In addition, pathogenic bacteria, such as Enterobacter cloacae, Klebsiella oxytoca, Erwinia billingiae, and Pantoea vagan were detected in Shenqu. DGGE analysis showed that bacterial and fungal diversity declined over the course of fermentation. This determination of the predominant bacterial and fungal strains responsible for fermentation may contribute to further Shenqu research, such as optimization of the fermentation process. Copyright © 2017. Published by Elsevier Editora Ltda.

  11. Characterization of bacterial consortium and its application in an ectopic fermentation system.

    PubMed

    Guo, Hui; Geng, Bing; Liu, Xue; Ye, Jing; Zhao, Yongkun; Zhu, Changxiong; Yuan, Hongli

    2013-07-01

    This study aimed to develop an ectopic fermentation system (EFS) to reduce the pollution of cow wastewater and to provide a basis for the production of biofertilizer with fermentation residues. Six thermophilic strains, three of which have efficient cellulose-degrading abilities and the other have good ammonia-N utilizing abilities, were chosen as the microbial inocula. The results showed that EFS inoculated with microbial consortium brought higher temperature and more wastewater was needed to ensure continuous fermentation. The pH values decreased in the early stage of fermentation, and then increased during the process. It caused increases in total Kjeldahl nitrogen, total phosphorous, and total potassium content. Decreases in organic matter content and C/N ratio were also observed. The high level of nutrients indicated the suitability of the paddings after fermentation for agronomic uses. It firstly attempted to combine cow wastewater treatment and bio-organic fertilizer production by EFS with mixed microbial culture. Copyright © 2013 Elsevier Ltd. All rights reserved.

  12. Scale-up and integration of alkaline hydrogen peroxide pretreatment, enzymatic hydrolysis, and ethanolic fermentation.

    PubMed

    Banerjee, Goutami; Car, Suzana; Liu, Tongjun; Williams, Daniel L; Meza, Sarynna López; Walton, Jonathan D; Hodge, David B

    2012-04-01

    Alkaline hydrogen peroxide (AHP) has several attractive features as a pretreatment in the lignocellulosic biomass-to-ethanol pipeline. Here, the feasibility of scaling-up the AHP process and integrating it with enzymatic hydrolysis and fermentation was studied. Corn stover (1 kg) was subjected to AHP pretreatment, hydrolyzed enzymatically, and the resulting sugars fermented to ethanol. The AHP pretreatment was performed at 0.125 g H(2) O(2) /g biomass, 22°C, and atmospheric pressure for 48 h with periodic pH readjustment. The enzymatic hydrolysis was performed in the same reactor following pH neutralization of the biomass slurry and without washing. After 48 h, glucose and xylose yields were 75% and 71% of the theoretical maximum. Sterility was maintained during pretreatment and enzymatic hydrolysis without the use of antibiotics. During fermentation using a glucose- and xylose-utilizing strain of Saccharomyces cerevisiae, all of the Glc and 67% of the Xyl were consumed in 120 h. The final ethanol titer was 13.7 g/L. Treatment of the enzymatic hydrolysate with activated carbon prior to fermentation had little effect on Glc fermentation but markedly improved utilization of Xyl, presumably due to the removal of soluble aromatic inhibitors. The results indicate that AHP is readily scalable and can be integrated with enzyme hydrolysis and fermentation. Compared to other leading pretreatments for lignocellulosic biomass, AHP has potential advantages with regard to capital costs, process simplicity, feedstock handling, and compatibility with enzymatic deconstruction and fermentation. Biotechnol. Bioeng. 2012; 109:922-931. © 2011 Wiley Periodicals, Inc. Copyright © 2011 Wiley Periodicals, Inc.

  13. Influence of hepatic load from far-off dry period to early postpartum period on the first postpartum ovulation and accompanying subsequent fertility in dairy cows.

    PubMed

    Kawashima, Chiho; Ito, Nozomi; Nagashima, Shuntarou; Matsui, Motozumi; Sawada, Kumiko; Schweigert, Florian J; Miyamoto, Akio; Kida, Katsuya

    2016-06-17

    The aim of the present study was to investigate nutritional and metabolic parameters during the dry and early postpartum periods of ovulatory and anovulatory cows, as well as their postpartum reproductive performance. Blood samples from 20 multiparous Holstein cows were collected once a week from the far-off dry period to 3 weeks postpartum. Early postpartum (0-3 weeks) ovulation was confirmed using plasma progesterone concentration profiles, and cows were considered ovulatory if they had resumed luteal activity by this point (n = 9), whereas cows that had not were considered anovulatory (n = 11). Data from the ovulatory and anovulatory cows were analyzed separately for the far-off dry period (7-4 weeks prepartum), the close-up dry period (3-1 weeks prepartum), and the early postpartum period (0-3 weeks). Serum gamma-glutamyl transpeptidase activity (far-off, P = 0.065; close-up, P = 0.051; and early postpartum, P = 0.030) and aspartate aminotransferase (close-up, P = 0.050 and early postpartum, P = 0.087) activities were higher in anovulatory than in ovulatory cows. The days open period was longer (P = 0.019) in anovulatory than in ovulatory cows, and the number of artificial inseminations per conception (P = 0.025) was greater. In conclusion, we found that continuously high gamma-glutamyl transpeptidase activities in serum, which may be induced by liver disorders, prevent subsequent ovulation and affect subsequent fertility, even if cows obtain sufficient ovulation-related energy and β-carotene.

  14. Early Period of Modern Architecture in Turkey - A Case Study of Eskisehir

    NASA Astrophysics Data System (ADS)

    Karasozen, Rana

    2017-10-01

    Modern architecture in the Western World bore fruit at the beginning of the 20th Century in consequence of the process of modernity and seeking of the proper architecture for it. It was formed firstly towards the end of the 1920s. The main reason of this nonsynchronous development was the inadequacy of enlightenment and industrial revolution during the Ottoman Empire and the lack of formation of an intellectual infrastructure which provides the basis of modernity. However, the Ottoman Westernization occurring in the 19th century constituted the foundations of the Republic modernity founded in 1923. The earliest modern architectural designs in Turkey were first practised by European architects after the foundation of the Republic and internalised and practised extensively by the native architects afterwards. The early modern architecture of Turkey, named as “1930s Modernism”, continued until the beginning of the World War II. This period was formed in between the periods of first and second nationalist architecture movements. The early modern architecture period of Turkey was a period which high-quality designs were made. It was practised and internalised not only in big cities such as Ankara and in Istanbul, but also in the medium and small cities of the country. This situation was not just about a formal exception but about the internalisation of modernity by the society. Eskisehir is one of the most important pioneering cities of the Republic period in terms of industrial and educational developments. The earliest modern buildings were built as the public buildings by the state and non-citizen architects in the inadequate conditions of the country in terms of economy and professional people. The earliest modern houses of the city designed by these architects were the prototypes for the later practices which offered the citizens a new lifestyle. The modern houses were the symbols of prestige and status for the owners and the dwellers. The features of early

  15. Comprehensive assessment of the L-lysine production process from fermentation of sugarcane molasses.

    PubMed

    Anaya-Reza, Omar; Lopez-Arenas, Teresa

    2017-07-01

    L-Lysine is an essential amino acid that can be produced by chemical processes from fossil raw materials, as well as by microbial fermentation, the latter being a more efficient and environmentally friendly procedure. In this work, the production process of L-lysine-HCl is studied using a systematic approach based on modeling and simulation, which supports decision making in the early stage of process design. The study considers two analysis stages: first, the dynamic analysis of the fermentation reactor, where the conversion of sugars from sugarcane molasses to L-lysine with a strain of Corynebacterium glutamicum is carried out. In this stage, the operation mode (either batch or fed batch) and operating conditions of the fermentation reactor are defined to reach the maximum technical criteria. Afterwards, the second analysis stage relates to the industrial production process of L-lysine-HCl, where the fermentation reactor, upstream processing, and downstream processing are included. In this stage, the influence of key parameters on the overall process performance is scrutinized through the evaluation of several technical, economic, and environmental criteria, to determine a profitable and sustainable design of the L-lysine production process. The main results show how the operating conditions, process design, and selection of evaluation criteria can influence in the conceptual design. The best plant design shows maximum product yield (0.31 g L-lysine/g glucose) and productivity (1.99 g/L/h), achieving 26.5% return on investment (ROI) with a payback period (PBP) of 3.8 years, decreasing water and energy consumption, and with a low potential environmental impact (PEI) index.

  16. The Fermentative and Aromatic Ability of Kloeckera and Hanseniaspora Yeasts

    NASA Astrophysics Data System (ADS)

    Díaz-Montaño, Dulce M.; de Jesús Ramírez Córdova, J.

    Spontaneous alcoholic fermentation from grape, agave and others musts into an alcoholic beverage is usually characterized by the presence of several non-Saccharomyces yeasts. These genera yeasts are dominant in the early stages of the alcoholic fermentation. However the genera Hanseniaspora and Kloeckera may survive at a significant level during fermentation and can influence the chemical composition of the beverage. Several strains belonging to the species Kloeckera api-culata and Hanseniaspora guilliermondii have been extensively studied in relation to the formation of some metabolic compounds affecting the bouquet of the final product. Indeed some apiculate yeast showed positive oenological properties and their use in the alcoholic fermentations has been suggested to enhance the aroma and flavor profiles. The non- Saccharomyces yeasts have the capability to produce and secrete enzymes in the medium, such as β -glucosidases, which release monoterpenes derived from their glycosylated form. These compounds contribute to the higher fruit-like characteristic of final product. This chapter reviews metabolic activity of Kloeckera and Hanseniaspora yeasts in several aspects: fermentative capability, aromatic compounds production and transformation of aromatic precursor present in the must, also covers the molecular methods for identifying of the yeast

  17. Characterization of fermented black soybean natto inoculated with Bacillus natto during fermentation.

    PubMed

    Hu, Yongjin; Ge, Changrong; Yuan, Wei; Zhu, Renjun; Zhang, Wujiu; Du, Lijuan; Xue, Jie

    2010-05-01

    To make nutrients more accessible and further increase biological activity, cooked black soybeans were inoculated with Bacillus natto and fermented at 37 degrees C for 48 h. The changes in physiochemical properties of fermented black soybean natto were investigated. The inoculation procedure significantly increased moisture, viscosity, color, polyphenol compounds and anthocyanin, and significantly decreased hardness after 48 h fermentation. Fibrinolytic and caseinolytic protease, beta-glucosidase activities, TCA-soluble nitrogen, and ammonia nitrogen contents in the inoculated samples significantly increased as fermentation time increased. Genistin and daidzin concentrations gradually decreased with increased fermentation time. However, genistein and daidzein increased with fermentation time, which reached 316.8 and 305.2 microg g(-1) during 48 h fermentation, respectively. DPPH radical scavenging activities of the fermented black soybeans increased linearly with fermentation time and concentration. Compared with the soaked black soybeans and cooked black soybeans, the fermented black soybeans with B. natto resulted in higher scavenging activity towards DPPH radicals, which correlated well with the content of total phenols (r = 0.9254, P < 0.05) and aglycone isoflavone (r = 0.9861, P < 0.05). Black soybean natto fermented by B. natto has the potential to become a functional food because of its high antioxidant activity.

  18. Effect of the environment microbiota on the flavour of light-flavour Baijiu during spontaneous fermentation.

    PubMed

    Pang, Xiao-Na; Han, Bei-Zhong; Huang, Xiao-Ning; Zhang, Xin; Hou, Lin-Feng; Cao, Ming; Gao, Li-Juan; Hu, Guang-Hui; Chen, Jing-Yu

    2018-02-21

    Light-flavour Baijiu is a type of Chinese liquor with a pure and mild flavour produced by traditional spontaneous solid-state fermentation. The flavour of this liquor has been found to vary in the different periods of annual production. To explore the factors affecting flavour, the microbiota of the surrounding environment, starter and fermentation process in different periods were investigated. Results showed that the ester content and acidity of light-flavour Baijiu were significantly lower when annual production was resumed after a summer break. HCA plot of volatile flavour profile and bacterial PCoA results indicated that the differences occurred at later stages, mainly due to different structures of Lactobacillus. Correlation analysis by O2PLS indicated that Lactobacillus positively correlated with esters. Species-level analysis showed that the lack of L. acetotolerans on the surface of the jar might cause a lag in fermentation and lower ester content. Thereafter, L. acetotolerans was revived during fermentation and enriched on the surface of the jar, which promoted ester formation. As important sources of L. acetotolerans, the air and fermentation jars played a critical role during fermentation. Therefore, this systematic study on environmental microbial ecology is valuable for quality control and to explore environmental microbiota functions during spontaneous fermentation.

  19. Omega-3 production by fermentation of Yarrowia lipolytica: From fed-batch to continuous.

    PubMed

    Xie, Dongming; Miller, Edward; Sharpe, Pamela; Jackson, Ethel; Zhu, Quinn

    2017-04-01

    The omega-3 fatty acid, cis-5,8,11,14,17-eicosapentaenoic acid (C20:5; EPA) has wide-ranging benefits in improving heart health, immune function, and mental health. A sustainable source of EPA production through fermentation of metabolically engineered Yarrowia lipolytica has been developed. In this paper, key fed-batch fermentation conditions were identified to achieve 25% EPA in the yeast biomass, which is so far the highest EPA titer reported in the literature. Dynamic models of the EPA fermentation process were established for analyzing, optimizing, and scaling up the fermentation process. In addition, model simulations were used to develop a two-stage continuous process and compare to single-stage continuous and fed- batch processes. The two stage continuous process, which is equipped with a smaller growth fermentor (Stage 1) and a larger production fermentor (Stage 2), was found to be a superior process to achieve high titer, rate, and yield of EPA. A two-stage continuous fermentation experiment with Y. lipolytica strain Z7334 was designed using the model simulation and then tested in a 2 L and 5 L fermentation system for 1,008 h. Compared with the standard 2 L fed-batch process, the two-stage continuous fermentation process improved the overall EPA productivity by 80% and EPA concentration in the fermenter by 40% while achieving comparable EPA titer in biomass and similar conversion yield from glucose. During the long-term experiment it was also found that the Y. lipolytica strain evolved to reduce byproduct and increase lipid production. This is one of the few continuous fermentation examples that demonstrated improved productivity and concentration of a final product with similar conversion yield compared with a fed-batch process. This paper suggests the two-stage continuous fermentation could be an effective process to achieve improved production of omega-3 and other fermentation products where non-growth or partially growth associated kinetics

  20. Recent advances to improve fermentative butanol production: genetic engineering and fermentation technology.

    PubMed

    Zheng, Jin; Tashiro, Yukihiro; Wang, Qunhui; Sonomoto, Kenji

    2015-01-01

    Butanol has recently attracted attention as an alternative biofuel because of its various advantages over other biofuels. Many researchers have focused on butanol fermentation with renewable and sustainable resources, especially lignocellulosic materials, which has provided significant progress in butanol fermentation. However, there are still some drawbacks in butanol fermentation in terms of low butanol concentration and productivity, high cost of feedstock and product inhibition, which makes butanol fermentation less competitive than the production of other biofuels. These hurdles are being resolved in several ways. Genetic engineering is now available for improving butanol yield and butanol ratio through overexpression, knock out/down, and insertion of genes encoding key enzymes in the metabolic pathway of butanol fermentation. In addition, there are also many strategies to improve fermentation technology, such as multi-stage continuous fermentation, continuous fermentation integrated with immobilization and cell recycling, and the inclusion of additional organic acids or electron carriers to change metabolic flux. This review focuses on the most recent advances in butanol fermentation especially from the perspectives of genetic engineering and fermentation technology. Copyright © 2014 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  1. Extractive fermentation for enhanced propionic acid production from lactose by Propionibacterium acidipropionici

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Jin, Z.; Yang, S.T.

    1998-05-01

    An extractive fermentation process using an amine extractant and a hollow-fiber membrane extractor to selectively remove propionic acid from the fermentation broth was developed to produce propionate from lactose. Compared to the conventional batch fermentation, the extractive fermentation had a much higher productivity ({approximately}1 g/(L{center_dot}h) or 5-fold increase), higher propionate yield (up to 0.66 g/g or more than 20% increase), higher final product concentration (75 g/L or higher), and higher product purity ({approximately}90%). Meanwhile, acetate and succinate productions in the extractive fermentation were significantly reduced. The improved fermentation performance can be attributed to the reduced product inhibition and a possiblemore » metabolic pathway shift to favor more propionic but less acetic and succinic acid production. The process was stable and gave consistent long-term performance over the 1.5-month period studied. The effects of propionate concentration, pH, and amine content in the solvent on the extractive fermentation were also studied and are discussed in this paper.« less

  2. Microbial diversity and component variation in Xiaguan Tuo Tea during pile fermentation

    PubMed Central

    Li, Min; Yang, Xinrui; Gui, Xin; Chen, Guofeng; Chu, Jiuyun; He, Xingwang; Wang, Weitao; Han, Feng

    2018-01-01

    Xiaguan Tuo Tea is largely consumed by the Chinese, but there is little research into the microbial diversity and component changes during the fermentation of this tea. In this study, we first used fluorescence in situ hybridization (FISH), next-generation sequencing (NGS) and chemical analysis methods to determine the microbial abundance and diversity and the chemical composition during fermentation. The FISH results showed that the total number of microorganisms ranges from 2.3×102 to 4.0×108 cells per gram of sample during fermentation and is mainly dominated by fungi. In the early fermentation stages, molds are dominant (0.6×102~2.8×106 cells/g, 0~35 d). However, in the late stages of fermentation, yeasts are dominant (3.6×104~9.6×106 cells/g, 35~56 d). The bacteria have little effect during the fermentation of tea (102~103 cells/g, <1% of fungus values). Of these fungi, A. niger (Aspergillus niger) and B. adeninivorans (Blastobotrys adeninivorans) are identified as the two most common strains, based on Next-generation Sequencing (NGS) analysis. Peak diversity in tea was observed at day 35 of fermentation (Shannon–Weaver index: 1.195857), and lower diversity was observed on days 6 and 56 of fermentation (Shannon–Weaver index 0.860589 and 1.119106, respectively). During the microbial fermentation, compared to the unfermented tea, the tea polyphenol content decreased by 54%, and the caffeine content increased by 59%. Theanine and free amino acid contents were reduced during fermentation by 81.1 and 92.85%, respectively. PMID:29462204

  3. Microbial diversity and component variation in Xiaguan Tuo Tea during pile fermentation.

    PubMed

    Li, Haizhou; Li, Min; Yang, Xinrui; Gui, Xin; Chen, Guofeng; Chu, Jiuyun; He, Xingwang; Wang, Weitao; Han, Feng; Li, Ping

    2018-01-01

    Xiaguan Tuo Tea is largely consumed by the Chinese, but there is little research into the microbial diversity and component changes during the fermentation of this tea. In this study, we first used fluorescence in situ hybridization (FISH), next-generation sequencing (NGS) and chemical analysis methods to determine the microbial abundance and diversity and the chemical composition during fermentation. The FISH results showed that the total number of microorganisms ranges from 2.3×102 to 4.0×108 cells per gram of sample during fermentation and is mainly dominated by fungi. In the early fermentation stages, molds are dominant (0.6×102~2.8×106 cells/g, 0~35 d). However, in the late stages of fermentation, yeasts are dominant (3.6×104~9.6×106 cells/g, 35~56 d). The bacteria have little effect during the fermentation of tea (102~103 cells/g, <1% of fungus values). Of these fungi, A. niger (Aspergillus niger) and B. adeninivorans (Blastobotrys adeninivorans) are identified as the two most common strains, based on Next-generation Sequencing (NGS) analysis. Peak diversity in tea was observed at day 35 of fermentation (Shannon-Weaver index: 1.195857), and lower diversity was observed on days 6 and 56 of fermentation (Shannon-Weaver index 0.860589 and 1.119106, respectively). During the microbial fermentation, compared to the unfermented tea, the tea polyphenol content decreased by 54%, and the caffeine content increased by 59%. Theanine and free amino acid contents were reduced during fermentation by 81.1 and 92.85%, respectively.

  4. Applied in situ product recovery in ABE fermentation.

    PubMed

    Outram, Victoria; Lalander, Carl-Axel; Lee, Jonathan G M; Davies, E Timothy; Harvey, Adam P

    2017-05-01

    The production of biobutanol is hindered by the product's toxicity to the bacteria, which limits the productivity of the process. In situ product recovery of butanol can improve the productivity by removing the source of inhibition. This paper reviews in situ product recovery techniques applied to the acetone butanol ethanol fermentation in a stirred tank reactor. Methods of in situ recovery include gas stripping, vacuum fermentation, pervaporation, liquid-liquid extraction, perstraction, and adsorption, all of which have been investigated for the acetone, butanol, and ethanol fermentation. All techniques have shown an improvement in substrate utilization, yield, productivity or both. Different fermentation modes favored different techniques. For batch processing gas stripping and pervaporation were most favorable, but in fed-batch fermentations gas stripping and adsorption were most promising. During continuous processing perstraction appeared to offer the best improvement. The use of hybrid techniques can increase the final product concentration beyond that of single-stage techniques. Therefore, the selection of an in situ product recovery technique would require comparable information on the energy demand and economics of the process. © 2017 American Institute of Chemical Engineers Biotechnol. Prog., 33:563-579, 2017. © 2017 The Authors Biotechnology Progress published by Wiley Periodicals, Inc. on behalf of American Institute of Chemical Engineers.

  5. Enzymatic hydrolysis and fermentation of corn for fuel alcohol

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Mullins, J.T.

    1985-01-01

    The integration of enzyme saccharification with fermentation reduces the total time required to produce acceptable levels of ethanol. The use of a more concentrated mash (84.8 L total mash/bu corn) results in a 26.6% increase in ethanol productivity and a 21.4% increase in beer ethanol concentration compared to standard corn mash (96.6 L total mash/bu corn). Thus, the energy requirement and cost of distillation can be reduced. The addition of waste cola syrup at 30 g invert sugar/L total mash gave a 19% increase in ethanol concentration in the final beer and required only a small increase in period ofmore » fermentation. Surplus laundry starch can replace 30-50% of the weight of corn normally used in fermentation without influencing ethanol production or the time required for fermentation. Both of these waste materials reduce the unit cost of ethanol and demonstrate the value of such substances in ethanol systems.« less

  6. Change of Monascus pigment metabolism and secretion in different extractive fermentation process.

    PubMed

    Chen, Gong; Tang, Rui; Tian, Xiaofei; Qin, Peng; Wu, Zhenqiang

    2017-06-01

    Monascus pigments that were generally produced intracellularly from Monascus spp. are important natural colorants in food industry. In this study, change of pigment metabolism and secretion was investigated through fed-batch extractive fermentation and continuous extractive fermentation. The biomass, secreting rate of pigment and total pigment yield closely correlated with the activated time of extractive fermentation as well as the composition of feeding nutrients. Metal ions played a key role in both the cell growth and pigment metabolism. Nitrogen source was necessary for a high productivity of biomass but not for high pigment yield. Furthermore, fermentation period for the fed-batch extractive fermentation could be reduced by 18.75% with a nitrogen source free feeding medium. Through a 30-day continuous extractive fermentation, the average daily productivity for total pigments reached 74.9 AU day -1 with an increase by 32.6 and 296.3% compared to that in a 6-day conventional batch fermentation and a 16-day fed-batch extractive fermentation, respectively. At the meantime, proportions of extracellular pigments increased gradually from 2.7 to 71.3%, and yellow pigments gradually became dominated in both intracellular and extracellular pigments in the end of continuous extractive fermentation. This findings showed that either fed-batch or continuous extractive fermentation acted as a promising method in the efficient production of Monascus pigments.

  7. In vitro investigation of anticancer and ACE-inhibiting activity, α-amylase and α-glucosidase inhibition, and antioxidant activity of camel milk fermented with camel milk probiotic: A comparative study with fermented bovine milk.

    PubMed

    Ayyash, Mutamed; Al-Nuaimi, Amna K; Al-Mahadin, Suheir; Liu, Shao-Quan

    2018-01-15

    This study aimed to investigate in vitro the health-promoting benefits (anticancer activity, α-amylase and α-glucosidase inhibition, angiotensin-converting-enzyme (ACE)-inhibition, antioxidant and proteolytic activity) of camel milk fermented with indigenous probiotic strains of Lactobacillus spp., compared with fermented bovine milk. The three camel milk probiotic strains Lb. reuteri-KX881777, Lb. plantarum-KX881772, Lb. plantarum-KX881779 and a control strain Lb. plantarum DSM2468 were employed to ferment camel and bovine milks separately. The proteolytic and antioxidant activity of water soluble extracts (WSEs) from all fermented camel milks were higher than those of fermented bovine milk. α-Amylase inhibition of WSEs were >34% in both milk types fermented with all strains during storage periods, except the WSE of camel milk fermented by Lp.K772. The highest ACE-inhibition of the WSE from camel milk fermented by Lr.K777 was >80%. The proliferations of Caco-2, MCF-7 and HELA cells were more inhibited when treated with the WSE of fermented camel milk. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. Microorganisms in Fermented Apple Beverages: Current Knowledge and Future Directions

    PubMed Central

    Le Guellec, Rozenn; Schlusselhuber, Margot; Laplace, Jean-Marie; Cretenet, Marina

    2017-01-01

    Production of fermented apple beverages is spread all around the world with specificities in each country. ‘French ciders’ refer to fermented apple juice mainly produced in the northwest of France and often associated with short periods of consumption. Research articles on this kind of product are scarce compared to wine, especially on phenomena associated with microbial activities. The wine fermentation microbiome and its dynamics, organoleptic improvement for healthy and pleasant products and development of starters are now widely studied. Even if both beverages seem close in terms of microbiome and process (with both alcoholic and malolactic fermentations), the inherent properties of the raw materials and different production and environmental parameters make research on the specificities of apple fermentation beverages worthwhile. This review summarizes current knowledge on the cider microbial ecosystem, associated activities and the influence of process parameters. In addition, available data on cider quality and safety is reviewed. Finally, we focus on the future role of lactic acid bacteria and yeasts in the development of even better or new beverages made from apples. PMID:28757560

  9. Microorganisms in Fermented Apple Beverages: Current Knowledge and Future Directions.

    PubMed

    Cousin, Fabien J; Le Guellec, Rozenn; Schlusselhuber, Margot; Dalmasso, Marion; Laplace, Jean-Marie; Cretenet, Marina

    2017-07-25

    Production of fermented apple beverages is spread all around the world with specificities in each country. 'French ciders' refer to fermented apple juice mainly produced in the northwest of France and often associated with short periods of consumption. Research articles on this kind of product are scarce compared to wine, especially on phenomena associated with microbial activities. The wine fermentation microbiome and its dynamics, organoleptic improvement for healthy and pleasant products and development of starters are now widely studied. Even if both beverages seem close in terms of microbiome and process (with both alcoholic and malolactic fermentations), the inherent properties of the raw materials and different production and environmental parameters make research on the specificities of apple fermentation beverages worthwhile. This review summarizes current knowledge on the cider microbial ecosystem, associated activities and the influence of process parameters. In addition, available data on cider quality and safety is reviewed. Finally, we focus on the future role of lactic acid bacteria and yeasts in the development of even better or new beverages made from apples.

  10. Fermentation of aqueous plant seed extracts by lactic acid bacteria

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Schafner, D.W.; Beuchat, R.L.

    1986-05-01

    The effects of lactic acid bacterial fermentation on chemical and physical changes in aqueous extracts of cowpea (Vigna unguiculata), peanut (Arachis hypogea), soybean (Glycine max), and sorghum (Sorghum vulgare) were studied. The bacteria investigated were Lactobacillus helveticus, L. delbrueckii, L. casei, L. bulgaricus, L. acidophilus, and Streptococcus thermophilus. Organisms were inoculated individually into all of the seed extracts; L. bulgaricus and S. thermophilus were also evaluated together as inocula for fermenting the legume extracts. During fermentation, bacterial population and changes in titratable acidity, pH, viscosity, and color were measured over a 72 h period at 37 degrees C. Maximum bacterialmore » populations, titratable acidity, pH, and viscosity varied depending upon the type of extract and bacterial strain. The maximum population of each organism was influenced by fermentable carbohydrates, which, in turn, influenced acid production and change in pH. Change in viscosity was correlated with the amount of protein and titratable acidity of products. Color was affected by pasteurization treatment and fermentation as well as the source of extract. In the extracts inoculated simultaneously with L. bulgaricus and S. thermophilus, a synergistic effect resulted in increased bacterial populations, titratable acidity, and viscosity, and decreased pH in all the legume extracts when compared to the extracts fermented with either of these organisms individually. Fermented extracts offer potential as substitutes for cultured dairy products. 24 references.« less

  11. A new strategy of glucose supply in a microbial fermentation model

    NASA Astrophysics Data System (ADS)

    Kasbawati, Gunawan, A. Y.; Sidarto, K. A.; Hertadi, R.

    2015-09-01

    Strategy of glucose supply to achieve an optimal productivity of ethanol production of a yeast cell is one of the main features in a microbial fermentation process. Beside a known continuous glucose supply, in this study we consider a new supply strategy so called the on-off supply. An optimal control theory is applied to the fermentation system to find the optimal rate of glucose supply and time of supply. The optimization problem is solved numerically using Differential Evolutionary algorithm. We find two alternative solutions that we can choose to get the similar result: either long period process with low supply or short period process with high glucose supply.

  12. Critical Thinking about Critical Periods. A Series from the National Center for Early Development and Learning.

    ERIC Educational Resources Information Center

    Bailey, Donald B., Jr., Ed.; Bruer, John T., Ed.; Symons, Frank J., Ed.; Lichtman, Jeff W., Ed.

    The concept of critical or sensitive periods in child development provides an example around which to organize discussion of what is known and not known about brain development and the implications of brain science on early childhood policy and practice. This book reviews the early history of critical periods and evidence for their existence in…

  13. Effect of Rice Bran and Wheat Fibers on Microbiological and Physicochemical Properties of Fermented Sausages during Ripening and Storage

    PubMed Central

    Jung, Ji-Taek; Lee, Jin-kyu; Choi, Yeong-Seok; Lee, Ju-Ho; Choi, Jung-Seok; Choi, Yang-Il; Chung, Yoon-Kyung

    2018-01-01

    Abstract This study investigated the effect of rice bran fiber (RBF) and wheat fibers (WF) on microbiological and physicochemical properties of fermented sausages during ripening and storage. The experimental design included three treatments: Control, no addition; RBF, 1.5%; and WF, 1.5%. During the ripening periods, the addition of dietary fibers rapidly decreased pH and maintained high water activity values of fermented sausages (p<0.05). Lactic acid bacteria were more prevalent in fermented sausages with rice bran fiber than control and sausages with added wheat fiber. During cold storage, lower pH was observed in sausages with dietary fibers (p<0.05), and the water activity and color values were reduced as the storage period lengthened. Fermented sausages containing dietary fibers were higher in lactic acid bacteria counts, volatile basic nitrogen and 2-thiobarbituric acid reactive substance values compared to the control (p<0.05). The results indicate that, the addition of dietary fibers in the fermented sausages promotes the growth of lactic bacteria and fermentation, and suggests that development of functional fermented sausages is possible. PMID:29805280

  14. Short communication: Effect of the addition of Bifidobacterium monocultures on the physical, chemical, and sensory characteristics of fermented goat milk.

    PubMed

    Mituniewicz-Małek, A; Ziarno, M; Dmytrów, I; Balejko, J

    2017-09-01

    The aim of the study was to use 3 monocultures of Bifidobacterium (Bifidobacterium animalis ssp. lactis AD600, Bifidobacterium animalis ssp. lactis BB-12, and Bifidobacterium longum AD50) in fermented goat milk to assess the microbial, physicochemical, rheological, and sensory quality of beverages during a 3-wk storage period at 5°C. The results indicated that selected bifidobacteria may be used for production of fermented goat milk because they comply with the minimum standards specified by the Food and Agriculture Organization of the United Nations and the World Health Organization during the entire period of storage. However, goat milk fermented by Bif. longum AD50 had less than 10 6 cfu/g after 21 d of storage. The acidity, acetaldehyde content, viscosity, and hardness of fermented goat milk beverages depended on the strain and the storage period. Sensory properties were similar and acceptable, with a tendency for the quality to be reduced with an extended storage time. Depending on the monoculture of bifidobacteria used to manufacture fermented goat milk, the product had a different pH value. Titratable acidity in all fermented goat milk increased significantly along with the time of storage. Our study has shown that monocultures of bifidobacteria had a significant effect on the content of acetaldehyde, but the lowest effect over the entire storage period was observed in goat milk fermented by Bif. animalis ssp. lactis BB-12. This sample also had the lowest viscosity values compared with other samples and the best organoleptic properties during a 3-wk storage period. Copyright © 2017 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  15. Do mature forest birds prefer early-successional habitat during the post-fledging period?

    Treesearch

    Carlin C. Chandler; David I. King; Richard B. Chandler

    2012-01-01

    Recent studies have highlighted the importance of the post-fledging period to bird populations, suggesting that the importance of this portion of the life cycle is equal to or greater than the nesting period. Nevertheless, few studies have compared abundance of forest nesting species between mature forest and early-successional habitats while controlling for...

  16. Effects of dietary fermented spent coffee ground on nutrient digestibility and nitrogen utilization in sheep

    PubMed Central

    Rim, Jong-su

    2018-01-01

    Objective The objective of the study was to determine the effect of fermented spent coffee ground (FSCG) on nutrient digestibility and nitrogen utilization in sheep. Methods Fermentation of spent coffee ground (SCG) was conducted using Lactobacillus plantrum. Fermentation was performed at moisture content of 70% and temperature of 39°C with anaerobic air tension for 48 h. Four adult rams (initial body weight = 56.8±0.4 kg) were housed in a respiration-metabolism chamber and the treatments were: i) control (Basal diet; 0% SCG or FSCG), ii) 10% level of SCG, iii) 10% level of FSCG, and iv) 20% level of FSCG in 4×4 Latin square design. Each dietary experiment period lasted for 18-d with a 14-d of adaptation period and a 4-d of sample collection period. Results In SCG fermentation experimental result, acid detergent insoluble nitrogen (ADIN) concentration of FSCG (64.5% of total N) was lower than that of non-fermented SCG (78.8% of total N). Digestibility of dry matter and organic matter was similar among treatment groups. Although crude protein (CP) digestibility of the control was greater than FSCG groups (p< 0.05), the 10% FSCG group showed greater CP digestibility and nitrogen retention than non-fermented 10% SCG group (p<0.05). Body weight gain and average daily gain were linearly decreased with increasing FSCG feeding level (p<0.05). When the feeding level of FSCG was increased, water intake was linearly increased (p<0.05). With an increasing FSCG level, dry matter intake did not differ among groups, although the gain to feed ratio tended to decrease with increasing level of FSCG (p<0.10). Conclusion Microbial fermentation of SCG can improve protein digestibility, thereby increasing CP digestibility and nitrogen utilization in sheep. Fermentation using microorganisms in feed ingredients with low digestibility could have a positive effect on improving the quality of raw feed. PMID:29103281

  17. Effects of dietary fermented spent coffee ground on nutrient digestibility and nitrogen utilization in sheep.

    PubMed

    Choi, Yongjun; Rim, Jong-Su; Na, Youngjun; Lee, Sang Rak

    2018-03-01

    The objective of the study was to determine the effect of fermented spent coffee ground (FSCG) on nutrient digestibility and nitrogen utilization in sheep. Fermentation of spent coffee ground (SCG) was conducted using Lactobacillus plantrum . Fermentation was performed at moisture content of 70% and temperature of 39°C with anaerobic air tension for 48 h. Four adult rams (initial body weight = 56.8±0.4 kg) were housed in a respiration-metabolism chamber and the treatments were: i) control (Basal diet; 0% SCG or FSCG), ii) 10% level of SCG, iii) 10% level of FSCG, and iv) 20% level of FSCG in 4×4 Latin square design. Each dietary experiment period lasted for 18-d with a 14-d of adaptation period and a 4-d of sample collection period. In SCG fermentation experimental result, acid detergent insoluble nitrogen (ADIN) concentration of FSCG (64.5% of total N) was lower than that of non-fermented SCG (78.8% of total N). Digestibility of dry matter and organic matter was similar among treatment groups. Although crude protein (CP) digestibility of the control was greater than FSCG groups (p< 0.05), the 10% FSCG group showed greater CP digestibility and nitrogen retention than non-fermented 10% SCG group (p<0.05). Body weight gain and average daily gain were linearly decreased with increasing FSCG feeding level (p<0.05). When the feeding level of FSCG was increased, water intake was linearly increased (p<0.05). With an increasing FSCG level, dry matter intake did not differ among groups, although the gain to feed ratio tended to decrease with increasing level of FSCG (p<0.10). Microbial fermentation of SCG can improve protein digestibility, thereby increasing CP digestibility and nitrogen utilization in sheep. Fermentation using microorganisms in feed ingredients with low digestibility could have a positive effect on improving the quality of raw feed.

  18. Effects of temperature on microbial succession and metabolite change during saeu-jeot fermentation.

    PubMed

    Lee, Se Hee; Jung, Ji Young; Jeon, Che Ok

    2014-04-01

    To investigate the effects of temperature on saeu-jeot (shrimp) fermentation, four sets of saeu-jeot samples with approximately 25% (w/v) NaCl were fermented at 10 °C, 15 °C, 20 °C, and 25 °C. The pH values of the 10 °C and 15 °C samples were relatively constant during the entire fermentation period, whereas those of the 20 °C and 25 °C samples gradually decreased after 25 days of fermentation. Quantitative PCR showed that the maximum bacterial abundance was greater in higher temperature samples, and the bacterial abundance in the 10 °C samples steadily decreased during the entire fermentation period. Community analysis using pyrosequencing revealed that the initially dominant Proteobacteria including Pseudoalteromonas, Photobacterium, Vibrio, Aliivibrio, and Enterovibrio were replaced rapidly with Firmicutes such as Psychrobacter, Staphylococcus, Salimicrobium, Alkalibacillus, and Halanaerobium as the fermentation progressed. However, Vibrio, Photobacterium, Aliivibrio, and Enterovibrio, which may include potentially pathogenic strains, remained even after 215 days in the 10 °C samples. Metabolite analysis using (1)H NMR showed that amino acid profiles and initial quick increases of glucose and glycerol were similar and independent of bacterial growth in all temperature samples. After 25 days of fermentation, the levels of glucose, glycerol, and trimethylamine N-oxide decreased with the growth of Halanaerobium and the increase of acetate, butyrate, and methylamines in the 20 °C and 25 °C samples although the amino acid concentrations steadily increased until approximately 105 days of fermentation. Statistical triplot analysis showed that the bacterial successions occurred similarly regardless of the fermentation temperature, and Halanaerobium was likely responsible for the production of acetate, butyrate, and methylamines. This study suggests that around 15 °C might be the optimum temperature for the production of safe and tasty saeu

  19. Yeast vitality during cider fermentation: assessment by energy metabolism.

    PubMed

    Dinsdale, M G; Lloyd, D; McIntyre, P; Jarvis, B

    1999-03-15

    In an apple juice-based medium, an ethanol-tolerant Australian wine-yeast used for cider manufacture produced more than 10% ethanol over a 5 week period. Growth of the inoculum (10(6) organisms ml(-1)) occurred to a population of 3.1 x 10(7) ml(-1) during the first few days; at the end of the fermentation only 5 x 10(5) yeasts ml(-1) could be recovered as colony-forming units on plates. Respiratory and fermentative activities were measured by mass spectrometric measurements (O2 consumption and CO2 and ethanol production) of washed yeast suspensions taken from the cider fermentation at intervals. Both endogenous and glucose-supported energy-yielding metabolism declined, especially during the first 20 days. Levels of adenine nucleotides also showed decreases after day 1, as did adenylate energy charge, although in a prolonged (16.5 week) fermentation the lowest value calculated was 0.55. AMP was released into the medium. 31P-NMR spectra showed that by comparison with aerobically grown yeast, that from the later stages of the cider fermentation showed little polyphosphate. However, as previously concluded from studies of 'acidification power' and fluorescent oxonol dye exclusion (Dinsdale et al., 1995), repitching of yeast indicated little loss of viability despite considerable loss of vitality.

  20. Fermentation Temperature Modulates Phosphatidylethanolamine and Phosphatidylinositol Levels in the Cell Membrane of Saccharomyces cerevisiae

    PubMed Central

    Henderson, Clark M.; Zeno, Wade F.; Lerno, Larry A.; Longo, Marjorie L.

    2013-01-01

    During alcoholic fermentation, Saccharomyces cerevisiae is exposed to a host of environmental and physiological stresses. Extremes of fermentation temperature have previously been demonstrated to induce fermentation arrest under growth conditions that would otherwise result in complete sugar utilization at “normal” temperatures and nutrient levels. Fermentations were carried out at 15°C, 25°C, and 35°C in a defined high-sugar medium using three Saccharomyces cerevisiae strains with diverse fermentation characteristics. The lipid composition of these strains was analyzed at two fermentation stages, when ethanol levels were low early in stationary phase and in late stationary phase at high ethanol concentrations. Several lipids exhibited dramatic differences in membrane concentration in a temperature-dependent manner. Principal component analysis (PCA) was used as a tool to elucidate correlations between specific lipid species and fermentation temperature for each yeast strain. Fermentations carried out at 35°C exhibited very high concentrations of several phosphatidylinositol species, whereas at 15°C these yeast strains exhibited higher levels of phosphatidylethanolamine and phosphatidylcholine species with medium-chain fatty acids. Furthermore, membrane concentrations of ergosterol were highest in the yeast strain that experienced stuck fermentations at all three temperatures. Fluorescence anisotropy measurements of yeast cell membrane fluidity during fermentation were carried out using the lipophilic fluorophore diphenylhexatriene. These measurements demonstrate that the changes in the lipid composition of these yeast strains across the range of fermentation temperatures used in this study did not significantly affect cell membrane fluidity. However, the results from this study indicate that fermenting S. cerevisiae modulates its membrane lipid composition in a temperature-dependent manner. PMID:23811519

  1. The effect of kimchi on the microbiological stability of fermented sausage.

    PubMed

    Park, Young-Seo; Lee, Joo-Yeon

    2012-12-01

    The effects of kimchi and freeze-dried kimchi-powder added to raw meat mixtures on the microbiological quality of fermented sausage were studied. The results clearly demonstrated that the lactic acid bacteria (LAB) integrated via the addition of kimchi as well as kimchi-powder were well adapted to the new habitat of fermenting sausage, reaching maximum numbers of 8.65-8.80 log₁₀ cfu/g after 1-2 days of fermentation. In all kimchi and kimchi-powder sausages, the growth of Enterobacteriaceae was completely inhibited throughout the processing period (<2 log₁₀ cfu/g). The sausage batches containing more than 10% kimchi and 2% kimchi-powder showed no growth of S. aureus, whereas the control and another kimchi sausage batch reflected the growth of S. aureus (3.68-4.72 log₁₀ cfu/g). As a result, the addition of kimchi (≥10%) and kimchi-powder to the sausage mixture prior to fermentation produced the microbiological stability required for fermented sausages. Copyright © 2012 Elsevier Ltd. All rights reserved.

  2. Effects of Temperature on Bacterial Communities and Metabolites during Fermentation of Myeolchi-Aekjeot, a Traditional Korean Fermented Anchovy Sauce.

    PubMed

    Jung, Ji Young; Lee, Hyo Jung; Chun, Byung Hee; Jeon, Che Ok

    2016-01-01

    Myeolchi-aekjeot (MA) in Korea is produced outdoors without temperature controls, which is a major obstacle to produce commercial MA products with uniform quality. To investigate the effects of temperature on MA fermentation, pH, bacterial abundance and community, and metabolites were monitored during fermentation at 15°C, 20°C, 25°C, and 30°C. Initial pH values were approximately 6.0, and pH values increased after approximately 42 days, with faster increases at higher temperatures. Bacterial abundances increased rapidly in all MA samples after quick initial decreases during early fermentation and then they again steadily decreased after reaching their maxima, which were significantly greater at higher temperatures. Bacterial community analysis revealed that Proteobacteria and Tenericutes were predominant in all initial MA samples, but they were rapidly displaced by Firmicutes as fermentation progressed. Photobacterium and Mycoplasma belonging to Proteobacteria and Tenericutes, respectively, which may include potentially pathogenic strains, were dominant in initial MA, but decreased with the growth of Chromohalobacter, which occurred faster at higher temperatures--they were dominant until 273 and 100 days at 15°C and 20°C, respectively, but not detected after 30 days at 25°C and 30°C. Chromohalobacter also decreased with the appearance of subsequent genera belonging to Firmicutes in all MA samples. Tetragenococcus, halophilic lactic acid bacteria, appeared predominantly at 20°C, 25°C, and 30°C; they were most abundant at 30°C, but not detected at 15°C. Alkalibacillus and Lentibacillus appeared as dominant genera with the decrease of Tetragenococcus at 25°C and 30°C, but only Lentibacillus was dominant at 15°C and 20°C. Metabolite analysis showed that amino acids related to tastes were major metabolites and their concentrations were relatively higher at high temperatures. This study suggests that high temperatures (approximately 30°C) may be

  3. Antioxidant and hypolipidemic effects of soymilk fermented via Lactococcus acidophilus MF204.

    PubMed

    Chen, Jie; Wu, Yan; Yang, Chunmei; Xu, Xuejiao; Meng, Yuecheng

    2017-12-13

    Previous studies have shown that fermentations can enhance the bioactivity and absorption rate of soybean products. Fermented soybean products can alleviate hyperlipidemia and decrease risks of atherosclerosis and cardiovascular diseases. This study aimed to investigate the effects and mechanisms of soymilk fermented by Lactococcus acidophilus on blood lipids and antioxidant enzyme activities of rats fed with a high fat diet. Sixty rats were randomly assigned to six groups: normal control group (NC), high-fat control group (HFC), positive control group (cholestyramine, PC), Lactococcus acidophilus group (LA), soymilk group (SM), and fermented soymilk group (FSM), respectively. The NC group was fed with a basic diet, while the other groups were fed with a high-fat diet. After the experimental period (6 W), rats were sacrificed by decapitation. Blood and liver were collected to measure the concentrations of lipids and antioxidant enzyme activities. Results demonstrated that fermented soymilk could regulate lipid levels, restore HDL-c and TG to normal levels, and lower the concentrations of LDL-c than hypolipidemic drugs in hyperlipidemia rats. More importantly, fermented soymilk caused significant reduction in arteriosclerosis index and coronary risk index. Fermented soymilk also improved antioxidant capacities of hyperlipidemia rats. The increase of aglycone isoflavones in fermented soymilk could explain the above phenomena. In conclusion, soymilk fermented by Lactococcus acidophilus reduced risks of arteriosclerosis and coronary heart disease by regulating lipid levels and improving the antioxidant capacities of hyperlipidemia rats.

  4. Defective quiescence entry promotes the fermentation performance of bottom-fermenting brewer's yeast.

    PubMed

    Oomuro, Mayu; Kato, Taku; Zhou, Yan; Watanabe, Daisuke; Motoyama, Yasuo; Yamagishi, Hiromi; Akao, Takeshi; Aizawa, Masayuki

    2016-11-01

    One of the key processes in making beer is fermentation. In the fermentation process, brewer's yeast plays an essential role in both the production of ethanol and the flavor profile of beer. Therefore, the mechanism of ethanol fermentation by of brewer's yeast is attracting much attention. The high ethanol productivity of sake yeast has provided a good basis from which to investigate the factors that regulate the fermentation rates of brewer's yeast. Recent studies found that the elevated fermentation rate of sake Saccharomyces cerevisiae species is closely related to a defective transition from vegetative growth to the quiescent (G 0 ) state. In the present study, to clarify the relationship between the fermentation rate of brewer's yeast and entry into G 0 , we constructed two types of mutant of the bottom-fermenting brewer's yeast Saccharomyces pastorianus Weihenstephan 34/70: a RIM15 gene disruptant that was defective in entry into G 0 ; and a CLN3ΔPEST mutant, in which the G 1 cyclin Cln3p accumulated at high levels. Both strains exhibited higher fermentation rates under high-maltose medium or high-gravity wort conditions (20° Plato) as compared with the wild-type strain. Furthermore, G 1 arrest and/or G 0 entry were defective in both the RIM15 disruptant and the CLN3ΔPEST mutant as compared with the wild-type strain. Taken together, these results indicate that regulation of the G 0 /G 1 transition might govern the fermentation rate of bottom-fermenting brewer's yeast in high-gravity wort. Copyright © 2016 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  5. Design and installation of a next generation pilot scale fermentation system.

    PubMed

    Junker, B; Brix, T; Lester, M; Kardos, P; Adamca, J; Lynch, J; Schmitt, J; Salmon, P

    2003-01-01

    Four new fermenters were designed and constructed for use in secondary metabolite cultivations, bioconversions, and enzyme production. A new PC/PLC-based control system also was implemented using GE Fanuc PLCs, Genius I/O blocks, and Fix Dynamics SCADA software. These systems were incorporated into an industrial research fermentation pilot plant, designed and constructed in the early 1980s. Details of the design of these new fermenters and the new control system are described and compared with the existing installation for expected effectiveness. In addition, the reasoning behind selection of some of these features has been included. Key to the design was the goal of preserving similarity between the new and previously existing and successfully utilized fermenter hardware and software installations where feasible but implementing improvements where warranted and beneficial. Examples of enhancements include strategic use of Inconel as a material of construction to reduce corrosion, piping layout design for simplified hazardous energy isolation, on-line calculation and control of nutrient feed rates, and the use of field I/O modules located near the vessel to permit low-cost addition of new instrumentation.

  6. Feed efficiency and the liver proteome of fattening lambs are modified by feed restriction during the suckling period.

    PubMed

    Santos, A; Valdés, C; Giráldez, F J; López, S; France, J; Frutos, J; Fernández, M; Andrés, S

    2018-01-24

    The present study was designed to describe the effects of early feed restriction of Merino lambs on feed efficiency during the fattening period by examining ruminal microbiota and fermentation parameters, gastrointestinal morphology, digestibility or liver proteome. In total, 24 male Merino lambs were randomly assigned to two experimental treatments (n=12 per treatment). Lambs of the first group (ad libitum (ADL)) were kept permanently with the dams, whereas the other 12 lambs (restricted (RES)) were milk restricted. When lambs reached a live BW (LBW) of 15 kg, all the animals were offered the same complete pelleted diet (35 g dry matter/kg LBW per day) until slaughter at a LBW of 27 kg. The RES lambs showed poorer feed efficiency during the fattening period when compared with the ADL group (feed to gain ratio, 3.69 v. 3.05, P<0.001). No differences were observed in ruminal microbiota, fermentation parameters or apparent digestibility. However, the proportion of the small intestine and the length of ileal villi were reduced in the RES lambs. In total, 26 spots/proteins were identified in the liver proteomic profile, with significant differences (P<0.05) between experimental treatments, suggesting a higher catabolism of proteins and a reduction in β-oxidation of fatty acids in RES lambs when compared with the ADL animals. In conclusion, early feed restriction of Merino lambs during the suckling period promotes long-term effects on the small intestine and the proteomic profile of the liver, which may influence the metabolic use of nutrients, thus negatively affecting feed efficiency during the fattening phase.

  7. [Isolation, identification and rumen fermentation characteristics of Propionibacterium acnes].

    PubMed

    Wu, Ling; Zhao, Mingjuan; Xia, Cheng; Ni, Hongbo; Zhang, Hongyou

    2009-02-01

    Characteristic of energy metabolism in ruminant is a negative energy balance in perinatal period. Propionic acid from ruminal microbe fermentation is a vital glyconeogenesis substrate for preventing negative energy balance. We isolated and screened a Propionibacterium acnes strain from health cow rumen fluid, and studied its rumen fermentation characteristics. A Propionibacterium acnes strain from rumen fluid of health cow with permanent rumen fistula under sterile condition was isolated by segregation procedure of anaerobic bacterium and Sodium Lactate Broth (SLB), and identified by extraction of the genome DNA, cloning of the 16S rRNA gene, and sequencing. We studied the effect of the strain on pH, volatile fatty acid and lactic acid in rumen fluid in vitro and in vivo. A bacterium isolated from health cow rumen fluid was identified as Propionibacterium acnes by morphology, biochemical characteristics and sequence homology. In vitro, pH in rumen fluid decreased to the lowest after rumen fermentation of the strain for 12 h, then increased gradually. However, concentration of volatile fatty acid, such as acetic acid, propionic acid and butyric acid, increased to the highest after rumen fermentation of the strain for 12 h, then decreased gradually in vitro. The concentration of lactic acid and ratio of acetate to propionate decreased overall in vitro. In vivo, pH in rumen fluid decreased overall, concentration, of the volatile fatty acid increased overall. A strain of Propionibacterium acnes was isolated successfully from health cow rumen fluid. It is an important basis to develop microecological preparation for preventing cows' negative energy balance in perinatal period in future.

  8. Fermented goats' milk produced with selected multiple starters as a potentially functional food.

    PubMed

    Minervini, Fabio; Bilancia, Maria Teresa; Siragusa, Sonya; Gobbetti, Marco; Caponio, Francesco

    2009-09-01

    A screening among five lactic acid bacteria, used alone or in combination, led to select a mixed starter (Streptococcus thermophilus CR12, Lactobacillus casei LC01, Lactobacillus helveticus PR4, Lactobacillus plantarum 1288) capable to produce a fermented goats' milk containing gamma-aminobutyric acid (GABA) and angiotensin-I converting enzyme (ACE)-inhibitory peptides. The fermented milk was characterized by cell counts of lactic acid bacteria not lower than 7.0 log cfu g(-1), even after 45 days of storage at 4 degrees C. Fermentation of goats' milk resulted in the production of ca. 28 mg kg(-1) of GABA. Furthermore the fermented goats' milk had an in vitro ACE-inhibitory activity of ca. 73%. Prolonged cold storage did not significantly affect both the concentration of GABA and the ACE-inhibitory activity. Moreover, the taurine content did not significantly vary during both fermentation and the entire storage period.

  9. Effects of koji fermented phenolic compounds on the oxidative stability of fish miso.

    PubMed

    Giri, Anupam; Osako, Kazufumi; Okamoto, Akira; Okazaki, Emiko; Ohshima, Toshiaki

    2012-02-01

    In the present study, Aspergillus oryzae-inoculated koji inhibited lipid oxidation in fermented fish paste rich in polyunsaturated fatty acids following a long fermentation period. The fermentation of koji by A. oryzae liberated several bioactive phenolic compounds, including kojic acid and ferulic acid, which were the most abundant. A linear correlation between several phenolic compounds and their bioactive properties, including their radical-scavenging activity, reducing power, metal-chelating activity, and ability to inhibit linoleic acid oxidation was observed. This suggested an important role of koji phenolics in the oxidative stability of fermented fish paste. The activities of different carbohydrate-cleaving enzymes, including α-amylase, cellulase, and β-glucosidase, were positively correlated with the liberation of several phenolic compounds through koji fermentation. Thus, the application of koji offers a novel strategy to enhance the oxidative stability of newly developed fermented fish miso. Application of traditional Japanese koji fermentation technique to develop an aroma enriched fish meat bases seasoning has been established. Aspergillus oryzae-inoculated koji releases several carbohydrate-cleaving enzymes, including α-amylase, cellulose, and β-glucosidase, which led to the liberation of several phenolic compounds during fermentation. Improvement of oxidative stability of the fermented fish meat paste by koji phenolics suggests a useful strategy to uplift the value of different trash fish meat-based seasoning through proper utilization of the present technique. © 2012 Institute of Food Technologists®

  10. Enzymes in Fermented Fish.

    PubMed

    Giyatmi; Irianto, H E

    Fermented fish products are very popular particularly in Southeast Asian countries. These products have unique characteristics, especially in terms of aroma, flavor, and texture developing during fermentation process. Proteolytic enzymes have a main role in hydrolyzing protein into simpler compounds. Fermentation process of fish relies both on naturally occurring enzymes (in the muscle or the intestinal tract) as well as bacteria. Fermented fish products processed using the whole fish show a different characteristic compared to those prepared from headed and gutted fish. Endogenous enzymes like trypsin, chymotrypsin, elastase, and aminopeptidase are the most involved in the fermentation process. Muscle tissue enzymes like cathepsins, peptidases, transaminases, amidases, amino acid decarboxylases, glutamic dehydrogenases, and related enzymes may also play a role in fish fermentation. Due to the decreased bacterial number during fermentation, contribution of microbial enzymes to proteolysis may be expected prior to salting of fish. Commercial enzymes are supplemented during processing for specific purposes, such as quality improvement and process acceleration. In the case of fish sauce, efforts to accelerate fermentation process and to improve product quality have been studied by addition of enzymes such as papain, bromelain, trypsin, pepsin, and chymotrypsin. © 2017 Elsevier Inc. All rights reserved.

  11. The preparation and ethanol fermentation of high-concentration sugars from steam-explosion corn stover.

    PubMed

    Xie, Hui; Wang, Fengqin; Yin, Shuangyao; Ren, Tianbao; Song, Andong

    2015-05-01

    In the field of biofuel ethanol, high-concentration- reducing sugars made from cellulosic materials lay the foundation for high-concentration ethanol fermentation. In this study, corn stover was pre-treated in a process combining chemical methods and steam explosion; the cellulosic hydrolyzed sugars obtained by fed-batch saccharification were then used as the carbon source for high-concentration ethanol fermentation. Saccharomyces cerevisiae 1308, Angel yeast, and Issatchenkia orientalis were shake-cultured with Pachysolen tannophilus P-01 for fermentation. Results implied that the ethanol yields from the three types of mixed strains were 4.85 g/100 mL, 4.57 g/100 mL, and 5.02 g/100 mL (separately) at yield rates of 91.6, 89.3, and 92.2%, respectively. Therefore, it was inferred that shock-fermentation using mixed strains achieved a higher ethanol yield at a greater rate in a shorter fermentation period. This study provided a theoretical basis and technical guidance for the fermentation of industrial high-concentrated cellulosic ethanol.

  12. Biogas production of Chicken Manure by Two-stage fermentation process

    NASA Astrophysics Data System (ADS)

    Liu, Xin Yuan; Wang, Jing Jing; Nie, Jia Min; Wu, Nan; Yang, Fang; Yang, Ren Jie

    2018-06-01

    This paper performs a batch experiment for pre-acidification treatment and methane production from chicken manure by the two-stage anaerobic fermentation process. Results shows that the acetate was the main component in volatile fatty acids produced at the end of pre-acidification stage, accounting for 68% of the total amount. The daily biogas production experienced three peak period in methane production stage, and the methane content reached 60% in the second period and then slowly reduced to 44.5% in the third period. The cumulative methane production was fitted by modified Gompertz equation, and the kinetic parameters of the methane production potential, the maximum methane production rate and lag phase time were 345.2 ml, 0.948 ml/h and 343.5 h, respectively. The methane yield of 183 ml-CH4/g-VSremoved during the methane production stage and VS removal efficiency of 52.7% for the whole fermentation process were achieved.

  13. Comparative fermentation behaviour and chemical characteristics of Saccharomyces and Zymomonas fermented culled apple juice.

    PubMed

    Sandhu, D K; Joshi, V K

    1994-12-01

    Ethanol production from culled apple juice showed that fermentability of the juice could be enhanced by addition of DAHP or ammonium sulphate in Saccharomyces and DAHP in Zymomonas fermentation. Addition of trace elements inhibited both the fermentations and ethanol, consequently. With respect to by-products of fermentation, no clear advantage of Zymomnas fermentation of culled apple juice could be observed. Differences in physico-chemical characteristics of the fermented apple juice were also noted. Saccharomyces cerevisiae proved to be better than Zymomonas in most of the parameters and is preferrable from handling and spoilage point of view.

  14. Glycerol production by fermenting yeast cells is essential for optimal bread dough fermentation.

    PubMed

    Aslankoohi, Elham; Rezaei, Mohammad Naser; Vervoort, Yannick; Courtin, Christophe M; Verstrepen, Kevin J

    2015-01-01

    Glycerol is the main compatible solute in yeast Saccharomyces cerevisiae. When faced with osmotic stress, for example during semi-solid state bread dough fermentation, yeast cells produce and accumulate glycerol in order to prevent dehydration by balancing the intracellular osmolarity with that of the environment. However, increased glycerol production also results in decreased CO2 production, which may reduce dough leavening. We investigated the effect of yeast glycerol production level on bread dough fermentation capacity of a commercial bakery strain and a laboratory strain. We find that Δgpd1 mutants that show decreased glycerol production show impaired dough fermentation. In contrast, overexpression of GPD1 in the laboratory strain results in increased fermentation rates in high-sugar dough and improved gas retention in the fermenting bread dough. Together, our results reveal the crucial role of glycerol production level by fermenting yeast cells in dough fermentation efficiency as well as gas retention in dough, thereby opening up new routes for the selection of improved commercial bakery yeasts.

  15. Bacterial dynamics during yearlong spontaneous fermentation for production of ngari, a dry fermented fish product of Northeast India.

    PubMed

    Devi, Khunjamayum Romapati; Deka, Manab; Jeyaram, Kumaraswamy

    2015-04-16

    Ngari is the most popular traditionally processed non-salted fish product, prepared from sun-dried small cyprinid fish Puntius sophore (Ham.) in Manipur state of Northeast India. The microbial involvement in ngari production remained uncertain due to its low moisture content and yearlong incubation in anaerobically sealed earthen pots without any significant change in total microbial count. The culture-independent PCR-DGGE analysis used during this study confirmed a drastic bacterial community structural change in comparison to its raw material. To understand the bacterial dynamics during this dry fermentation, time series samples collected over a period of nine months through destructive sampling from two indigenous ngari production centres were analysed by using both culture-dependent and culture-independent molecular methods. A total of 210 bacteria isolated from the samples were identified by amplified ribosomal DNA restriction analysis (ARDRA) based grouping and 16S rRNA gene sequence similarity analysis. The dominant bacteria were Staphylococcus cohnii subsp. cohnii (38.0%), Tetragenococcus halophilus subsp. flandriensis (16.8%), a novel phylotype related to Lactobacillus pobuzihii (7.2%), Enterococcus faecium (7.2%), Bacillus indicus (6.3%) and Staphylococcus carnosus (3.8%). Distinct bacterial dynamics with the emergence of T. halophilus at third month (10(6)CFU/g), L. pobuzihii at sixth month (10(6)CFU/g), S. carnosus at three to six months (10(4)CFU/g) and B. indicus at six to nine months (10(5)CFU/g) in both the production centres was observed during ngari fermentation. However, the other two dominant bacteria S. cohnii and E. faecium were isolated throughout the fermentation with the population of 10(6)CFU/g and 10(4)CFU/g respectively. Culture-independent PCR-DGGE analysis further showed the presence of additional species, in which Kocuria halotolerans and Macrococcus caseolyticus disappeared during fermentation while Clostridium irregulare and

  16. Energy Utilization for Polysaccharide Synthesis by Mixed Rumen Organisms Fermenting Soluble Carbohydrates

    PubMed Central

    Walker, D. J.

    1968-01-01

    Synthesis of reserve polysaccharide by mixed rumen organisms fermenting glucose, maltose, cellobiose, and xylose has been studied in relation to the adenosine triphosphate energy calculated to be available from substrate fermentation. About 80% of the energy available from glucose and xylose was used for polysaccharide synthesis, whereas, assuming hydrolytic cleavage of the disaccharides, more than 100% was used when cellobiose and maltose were the substrates. If, however, phosphorolytic cleavage of the disaccharides, for which there is evidence, was involved, the energy from both maltose and cellobiose fermentation was used with about the same efficiency as that from glucose and xylose fermentation. The rumen fluid used was collected 24 hr after feeding, and growth of microorganisms in such samples was sufficient to account for utilization of less than 10% of the total energy becoming available during the 40-min incubation period. PMID:16349819

  17. Cucumber fermentation

    USDA-ARS?s Scientific Manuscript database

    Humans have consumed fermented cucumber products since before the dawn of civilization. Although cucumber fermentation remains largely a traditional process, it has proven to be a consistently safe process by which raw cucumbers are transformed into high quality pickles that have a long shelf-life ...

  18. Fermentation performance optimization in an ectopic fermentation system.

    PubMed

    Yang, Xiaotong; Geng, Bing; Zhu, Changxiong; Li, Hongna; He, Buwei; Guo, Hui

    2018-07-01

    Ectopic fermentation systems (EFSs) were developed for wastewater treatment. Previous studies have investigated the ability of thermophilic bacteria to improve fermentation performance in EFS. Continuing this research, we evaluated EFS performance using principle component analysis and investigated the addition of different proportions of cow dung. Viable bacteria communities were clustered and identified using BOX-AIR-based repetitive extragenic palindromic-PCR and 16S rDNA analysis. The results revealed optimal conditions for the padding were maize straw inoculated with thermophilic bacteria. Adding 20% cow dung yielded the best pH values (6.94-8.56), higher temperatures, increased wastewater absorption, improved litter quality, and greater microbial quantities. The viable bacteria groups were enriched by the addition of thermophilic consortium, and exogenous strains G21, G14, G4-1, and CR-15 were detected in fermentation process. The proportion of Bacillus species in treatment groups reached 70.37% after fermentation, demonstrating that thermophilic bacteria, especially Bacillus, have an important role in EFS, supporting previous predictions. Copyright © 2018 Elsevier Ltd. All rights reserved.

  19. What Fermenter?

    ERIC Educational Resources Information Center

    Terry, John

    1987-01-01

    Discusses the feasibility of using fermenters in secondary school laboratories. Includes discussions of equipment, safety, and computer interfacing. Describes how a simple fermenter could be used to simulate large-scale processes. Concludes that, although teachers and technicians will require additional training, the prospects for biotechnology in…

  20. Fermentation performance of lager yeast in high gravity beer fermentations with different sugar supplementations.

    PubMed

    Lei, Hongjie; Xu, Huaide; Feng, Li; Yu, Zhimin; Zhao, Haifeng; Zhao, Mouming

    2016-11-01

    The effects of glucose, sucrose and maltose supplementations on the fermentation performance and stress tolerance of lager yeast (Saccharomyces pastorianus) during high gravity (18°P) and very high gravity (24°P) fermentations were studied. Results showed that throughout 18°P wort fermentation, fermentation performance of lager yeast was significantly improved by glucose or sucrose supplementation, compared with maltose supplementation, especially for sucrose supplementation increasing wort fermentability and ethanol production by 6% and 8%, respectively. However, in the later stage of 24°P wort fermentation, fermentation performance of lager yeast was dramatically improved by maltose supplementation, which increased wort fermentability and ethanol production by 14% and 10%, respectively, compared with sucrose supplementation. Furthermore, higher HSP12 expression level and more intracellular trehalose accumulation in yeast cells were observed by maltose supplementation with increase of the wort gravity from 18°P to 24°P, indicating higher stress response of yeast cells. The excretion of Gly and Ala, and the absorption of Pro in the later stage of fermentation were promoted by maltose supplementation. In addition, with increase of the wort gravity from 18°P to 24°P, higher alcohols level was decreased with maltose supplementation, while esters formation was increased significantly with glucose supplementation. This study suggested that the choice of optimal fermentable sugars maintaining better fermentation performance of lager yeast should be based on not only strain specificity, but also wort gravity. Copyright © 2016 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  1. Health benefits of fermented foods.

    PubMed

    Şanlier, Nevin; Gökcen, Büşra Başar; Sezgin, Aybüke Ceyhun

    2017-09-25

    In the past, the beneficial effects of fermented foods on health were unknown, and so people primarily used fermentation to preserve foods, enhance shelf life, and improve flavour. Fermented foods became an important part of the diet in many cultures, and over time fermentation has been associated with many health benefits. Because of this, the fermentation process and the resulting fermented products have recently attracted scientific interest. In addition, microorganisms contributing to the fermentation process have recently been associated with many health benefits, and so these microorganisms have become another focus of attention. Lactic acid bacteria (LAB) have been some of the most studied microorganisms. During fermentation, these bacteria synthesize vitamins and minerals, produce biologically active peptides with enzymes such as proteinase and peptidase, and remove some non-nutrients. Compounds known as biologically active peptides, which are produced by the bacteria responsible for fermentation, are also well known for their health benefits. Among these peptides, conjugated linoleic acids (CLA) have a blood pressure lowering effect, exopolysaccharides exhibit prebiotic properties, bacteriocins show anti-microbial effects, sphingolipids have anti-carcinogenic and anti-microbial properties, and bioactive peptides exhibit anti-oxidant, anti-microbial, opioid antagonist, anti-allergenic, and blood pressure lowering effects. As a result, fermented foods provide many health benefits such as anti-oxidant, anti-microbial, anti-fungal, anti-inflammatory, anti-diabetic and anti-atherosclerotic activity. However, some studies have shown no relationship between fermented foods and health benefits. Therefore, this paper aims to investigate the health effects of fermented foods.

  2. Fermented Milk Consumption and Common Infections in Children Attending Day-Care Centers: A Randomized Trial.

    PubMed

    Prodeus, Andrey; Niborski, Violeta; Schrezenmeir, Juergen; Gorelov, Alexander; Shcherbina, Anna; Rumyantsev, Alexander

    2016-11-01

    This multicenter, double-blind, randomized, placebo-controlled clinical trial investigated the effect of a fermented milk product containing the Lactobacillus casei National Collection of Microorganisms and Cell Cultures (CNCM) I-1518 strain on respiratory and gastrointestinal common infectious diseases (CIDs) in children attending day-care centers in Russia. Children ages 3 to 6 years received 100 g of a fermented milk product (n = 300) or a control product (n = 299) twice daily for 3 months, followed by a 1-month observation period. The primary outcome was the incidence of CIDs during the product consumption period. There was no significant difference in the incidence of CIDs between the groups (N = 98 with fermented milk product vs N = 93 with control product). The overall number of CIDs (and no severe cases at all) in both study groups and in all 12 centers, however, was unexpectedly low resulting in underpowering of the study. No differences were found between the groups in the duration or severity of disease, duration of sick leave from day-care centers, parental missed working days, or in quality-of-life dimensions on the PedsQL questionnaire (P > 0.05).There was, however, a significantly lower incidence of the most frequently observed CID, rhinopharyngitis, in children consuming the fermented milk product compared with those consuming the control product (N = 81 vs N = 100, relative risk 0.82, 95% confidence interval 0.69-0.96, P = 0.017) when considering the entire study period. Although no other significant differences were shown between the fermented milk and control product groups in this study, lower incidence of rhinopharyngitis may indicate a beneficial effect of this fermented milk product.

  3. Glycerol Production by Fermenting Yeast Cells Is Essential for Optimal Bread Dough Fermentation

    PubMed Central

    Aslankoohi, Elham; Rezaei, Mohammad Naser; Vervoort, Yannick; Courtin, Christophe M.; Verstrepen, Kevin J.

    2015-01-01

    Glycerol is the main compatible solute in yeast Saccharomyces cerevisiae. When faced with osmotic stress, for example during semi-solid state bread dough fermentation, yeast cells produce and accumulate glycerol in order to prevent dehydration by balancing the intracellular osmolarity with that of the environment. However, increased glycerol production also results in decreased CO2 production, which may reduce dough leavening. We investigated the effect of yeast glycerol production level on bread dough fermentation capacity of a commercial bakery strain and a laboratory strain. We find that Δgpd1 mutants that show decreased glycerol production show impaired dough fermentation. In contrast, overexpression of GPD1 in the laboratory strain results in increased fermentation rates in high-sugar dough and improved gas retention in the fermenting bread dough. Together, our results reveal the crucial role of glycerol production level by fermenting yeast cells in dough fermentation efficiency as well as gas retention in dough, thereby opening up new routes for the selection of improved commercial bakery yeasts. PMID:25764309

  4. Conversion of phenolic constituents in aqueous Hamamelis virginiana leaf extracts during fermentation.

    PubMed

    Duckstein, Sarina M; Lorenz, Peter; Stintzing, Florian C

    2012-01-01

    Hamamelis virginiana, known for its high level of tannins and other phenolics is widely used for treatment of dermatological disorders. Although reports on hydroalcoholic and aqueous extracts from Hamamelis leaf and bark exist, knowledge on fermented leaf preparations and the underlying conversion processes are still scant. Aqueous Hamamelis leaf extracts were monitored during fermentation and maturation in order to obtain an insight into the bioconversion of tannins and other phenolics. Aliquots taken during the production period were investigated by HPLC-DAD-MS/MS as well as GC-MS after derivatisation into the corresponding trimethylsilyl compounds. In Hamamelis leaf extracts, the main constituents exhibited changes during the observational period of 6 months. By successive depside bond cleavage, the gallotannins were completely transformed into gallic acid after 1 month. Although not completely, kaempferol and quercetin glycosides were also converted during 6 months to yield their corresponding aglycones. Following C-ring fission, phloroglucinol was formed from the A-ring of both flavonols. The B-ring afforded 3-hydroxybenzoic acid from quercetin and 3,4-dihydroxybenzoic acid as well as 2-(4-hydroxyphenyl)-ethanol from kaempferol. Interestingly, hydroxycinnamic acids remained almost stable in the same time range. The present study broadens the knowledge on conversion processes in aqueous fermented extracts containing tannins, flavonol glycosides and hydroxycinnamic acids. In particular, the analogy between the microbial metabolism of phenolics from fermented Hamamelis extracts, fermented sourdough by heterofermentative lactic acid bacteria or conversion of phenolics by the human microbial flora is indicated. Copyright © 2012 John Wiley & Sons, Ltd.

  5. New process for production of fermented black table olives using selected autochthonous microbial resources

    PubMed Central

    Tufariello, Maria; Durante, Miriana; Ramires, Francesca A.; Grieco, Francesco; Tommasi, Luca; Perbellini, Ezio; Falco, Vittorio; Tasioula-Margari, Maria; Logrieco, Antonio F.; Mita, Giovanni; Bleve, Gianluca

    2015-01-01

    Table olives represent one important fermented product in Europe and, in the world, their demand is constantly increasing. At the present time, no systems are available to control black table olives spontaneous fermentation by the Greek method. During this study, a new protocol for the production of black table olives belonging to two Italian (Cellina di Nardò and Leccino) and two Greek (Kalamàta and Conservolea) cultivars has been developed: for each table olive cultivar, starter-driven fermentations were performed inoculating, firstly, one selected autochthonous yeast starter and, subsequently, one selected autochthonous LAB starter. All starters formulation were able to dominate fermentation process. The olive fermentation was monitored using specific chemical descriptors able to identify a first stage (30 days) mainly characterized by aldehydes; a second period (60 days) mainly characterized by higher alcohols, styrene and terpenes; a third fermentation stage represented by acetate esters, esters and acids. A significant decrease of fermentation time (from 8 to 12 months to a maximum of 3 months) and an significant improvement in organoleptic characteristics of the final product were obtained. This study, for the first time, describes the employment of selected autochthonous microbial resources optimized to mimic the microbial evolution already recorded during spontaneous fermentations. PMID:26441932

  6. Ant colony system algorithm for the optimization of beer fermentation control.

    PubMed

    Xiao, Jie; Zhou, Ze-Kui; Zhang, Guang-Xin

    2004-12-01

    Beer fermentation is a dynamic process that must be guided along a temperature profile to obtain the desired results. Ant colony system algorithm was applied to optimize the kinetic model of this process. During a fixed period of fermentation time, a series of different temperature profiles of the mixture were constructed. An optimal one was chosen at last. Optimal temperature profile maximized the final ethanol production and minimized the byproducts concentration and spoilage risk. The satisfactory results obtained did not require much computation effort.

  7. The Effect of Proanthocyanidins on Growth and Alcoholic Fermentation of Wine Yeast under Copper Stress.

    PubMed

    Jia, Bo; Liu, Xingyan; Zhan, Jicheng; Li, Jingyuan; Huang, Weidong

    2015-06-01

    Proanthocyanidins (PAs) derived from the grape skin, as well as from grape seeds, grape stems, are an important group of polyphenols in wine. The aim of this study was to understand the effect of PAs (0.1, 1.0 g/L) on growth and alcoholic fermentation of 2 strains of Saccharomyces cerevisiae (commercial strain FREDDO and newly selected strain BH8) during copper-stress fermentation, using a simple model fermentation system. Our results showed that both PAs and Cu(2+) could pose significant inhibition effects on the growth of yeast cells, CO2 release, sugar consumption, and ethanol production during the initial phase of the fermentation. Compared to PAs, Cu(2+) performed more obvious inhibition on the yeast growth and fermentation. However, adding 1.0 g/L PAs increased in the vitality and metabolism activity of yeast cells at the mid-exponential phase of fermentation in the mediums with no copper and 0.1 mM Cu(2+) added, shortened the period of wine fermentation, and decreased the copper residues. It indicated that PAs could improve the ability of wine yeast to resist detrimental effects under copper-stress fermentation condition, maintaining cells metabolic activity, and fermentation could be controlled by manipulating PAs supplementation. © 2015 Institute of Food Technologists®

  8. Early Seizures Prematurely Unsilence Auditory Synapses to Disrupt Thalamocortical Critical Period Plasticity.

    PubMed

    Sun, Hongyu; Takesian, Anne E; Wang, Ting Ting; Lippman-Bell, Jocelyn J; Hensch, Takao K; Jensen, Frances E

    2018-05-29

    Heightened neural excitability in infancy and childhood results in increased susceptibility to seizures. Such early-life seizures are associated with language deficits and autism that can result from aberrant development of the auditory cortex. Here, we show that early-life seizures disrupt a critical period (CP) for tonotopic map plasticity in primary auditory cortex (A1). We show that this CP is characterized by a prevalence of "silent," NMDA-receptor (NMDAR)-only, glutamate receptor synapses in auditory cortex that become "unsilenced" due to activity-dependent AMPA receptor (AMPAR) insertion. Induction of seizures prior to this CP occludes tonotopic map plasticity by prematurely unsilencing NMDAR-only synapses. Further, brief treatment with the AMPAR antagonist NBQX following seizures, prior to the CP, prevents synapse unsilencing and permits subsequent A1 plasticity. These findings reveal that early-life seizures modify CP regulators and suggest that therapeutic targets for early post-seizure treatment can rescue CP plasticity. Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.

  9. Microbial Succession and Flavor Production in the Fermented Dairy Beverage Kefir.

    PubMed

    Walsh, Aaron M; Crispie, Fiona; Kilcawley, Kieran; O'Sullivan, Orla; O'Sullivan, Maurice G; Claesson, Marcus J; Cotter, Paul D

    2016-01-01

    Kefir is a putatively health-promoting dairy beverage that is produced when a kefir grain, consisting of a consortium of microorganisms, is added to milk to initiate a natural fermentation. Here, a detailed analysis was carried out to determine how the microbial population, gene content, and flavor of three kefirs from distinct geographic locations change over the course of 24-h fermentations. Metagenomic sequencing revealed that Lactobacillus kefiranofaciens was the dominant bacterial species in kefir during early stages of fermentations but that Leuconostoc mesenteroides became more prevalent in later stages. This pattern is consistent with an observation that genes involved in aromatic amino acid biosynthesis were absent from L. kefiranofaciens but were present in L. mesenteroides . Additionally, these shifts in the microbial community structure, and associated pathways, corresponded to changes in the levels of volatile compounds. Specifically, Acetobacter spp. correlated with acetic acid; Lactobacillus spp. correlated with carboxylic acids, esters and ketones; Leuconostoc spp. correlated with acetic acid and 2,3-butanedione; and Saccharomyces spp. correlated with esters. The correlation data suggest a causal relationship between microbial taxa and flavor that is supported by observations that addition of L. kefiranofaciens NCFB 2797 increased the levels of esters and ketones whereas addition of L. mesenteroides 213M0 increased the levels of acetic acid and 2,3-butanedione. Finally, we detected genes associated with probiotic functionalities in the kefir microbiome. Our results illustrate the dynamic nature of kefir fermentations and microbial succession patterns therein and can be applied to optimize the fermentation processes, flavors, and health-related attributes of this and other fermented foods. IMPORTANCE Traditional fermented foods represent relatively low-complexity microbial environments that can be used as model microbial communities to understand

  10. Effects of Temperature on Bacterial Communities and Metabolites during Fermentation of Myeolchi-Aekjeot, a Traditional Korean Fermented Anchovy Sauce

    PubMed Central

    Chun, Byung Hee; Jeon, Che Ok

    2016-01-01

    Myeolchi-aekjeot (MA) in Korea is produced outdoors without temperature controls, which is a major obstacle to produce commercial MA products with uniform quality. To investigate the effects of temperature on MA fermentation, pH, bacterial abundance and community, and metabolites were monitored during fermentation at 15°C, 20°C, 25°C, and 30°C. Initial pH values were approximately 6.0, and pH values increased after approximately 42 days, with faster increases at higher temperatures. Bacterial abundances increased rapidly in all MA samples after quick initial decreases during early fermentation and then they again steadily decreased after reaching their maxima, which were significantly greater at higher temperatures. Bacterial community analysis revealed that Proteobacteria and Tenericutes were predominant in all initial MA samples, but they were rapidly displaced by Firmicutes as fermentation progressed. Photobacterium and Mycoplasma belonging to Proteobacteria and Tenericutes, respectively, which may include potentially pathogenic strains, were dominant in initial MA, but decreased with the growth of Chromohalobacter, which occurred faster at higher temperatures––they were dominant until 273 and 100 days at 15°C and 20°C, respectively, but not detected after 30 days at 25°C and 30°C. Chromohalobacter also decreased with the appearance of subsequent genera belonging to Firmicutes in all MA samples. Tetragenococcus, halophilic lactic acid bacteria, appeared predominantly at 20°C, 25°C, and 30°C; they were most abundant at 30°C, but not detected at 15°C. Alkalibacillus and Lentibacillus appeared as dominant genera with the decrease of Tetragenococcus at 25°C and 30°C, but only Lentibacillus was dominant at 15°C and 20°C. Metabolite analysis showed that amino acids related to tastes were major metabolites and their concentrations were relatively higher at high temperatures. This study suggests that high temperatures (approximately 30°C) may be

  11. Between-cow variation in digestion and rumen fermentation variables associated with methane production.

    PubMed

    Cabezas-Garcia, E H; Krizsan, S J; Shingfield, K J; Huhtanen, P

    2017-06-01

    A meta-analysis based on an individual-cow data set was conducted to investigate the effects of between-cow variation and related animal variables on predicted CH 4 emissions from dairy cows. Data were taken from 40 change-over studies consisting of a total of 637 cow/period observations. Animal production and rumen fermentation characteristics were measured for 154 diets in 40 studies; diet digestibility was measured for 135 diets in 34 studies, and ruminal digestion kinetics was measured for 56 diets in 15 studies. The experimental diets were based on grass silage, with cereal grains or by-products as energy supplements, and soybean or canola meal as protein supplements. Average forage:concentrate ratio across all diets on a dry matter basis was 59:41. Methane production was predicted from apparently fermented substrate using stoichiometric principles. Data were analyzed by mixed-model regression using diet and period within experiment as random effects, thereby allowing the effect of experiment, diet, and period to be excluded. Dry matter intake and milk yield were more repeatable experimental measures than rumen fermentation, nutrient outflow, diet digestibility, or estimated CH 4 yield. Between-cow coefficient of variation (CV) was 0.010 for stoichiometric CH 4 per mol of volatile fatty acids and 0.067 for predicted CH 4 yield (CH 4 /dry matter intake). Organic matter digestibility (OMD) also displayed little between-cow variation (CV = 0.013), indicating that between-cow variation in diet digestibility and rumen fermentation pattern do not markedly contribute to between cow-variation in CH 4 yield. Digesta passage rate was much more variable (CV = 0.08) between cows than OMD or rumen fermentation pattern. Increased digesta passage rate is associated with improved energetic efficiency of microbial N synthesis, which partitions fermented substrate from volatile fatty acids and gases to microbial cells that are more reduced than fermented carbohydrates. Positive

  12. Biofilm formation and ethanol inhibition by bacterial contaminants of biofuel fermentation.

    PubMed

    Rich, Joseph O; Leathers, Timothy D; Bischoff, Kenneth M; Anderson, Amber M; Nunnally, Melinda S

    2015-11-01

    Bacterial contaminants can inhibit ethanol production in biofuel fermentations, and even result in stuck fermentations. Contaminants may persist in production facilities by forming recalcitrant biofilms. A two-year longitudinal study was conducted of bacterial contaminants from a Midwestern dry grind corn fuel ethanol facility. Among eight sites sampled in the facility, the combined liquefaction stream and yeast propagation tank were consistently contaminated, leading to contamination of early fermentation tanks. Among 768 contaminants isolated, 92% were identified as Lactobacillus sp., with the most abundant species being Lactobacillus plantarum, Lactobacillus casei, Lactobacillus mucosae, and Lactobacillus fermentum. Seven percent of total isolates showed the ability to form biofilms in pure cultures, and 22% showed the capacity to significantly inhibit ethanol production. However, these traits were not correlated. Ethanol inhibition appeared to be related to acetic acid production by contaminants, particularly by obligately heterofermentative species such as L. fermentum and L. mucosae. Published by Elsevier Ltd.

  13. Promoter engineering of the Saccharomyces cerevisiae RIM15 gene for improvement of alcoholic fermentation rates under stress conditions.

    PubMed

    Watanabe, Daisuke; Kaneko, Akie; Sugimoto, Yukiko; Ohnuki, Shinsuke; Takagi, Hiroshi; Ohya, Yoshikazu

    2017-02-01

    A loss-of-function mutation in the RIM15 gene, which encodes a Greatwall-like protein kinase, is one of the major causes of the high alcoholic fermentation rates in Saccharomyces cerevisiae sake strains closely related to Kyokai no. 7 (K7). However, impairment of Rim15p may not be beneficial under more severe fermentation conditions, such as in the late fermentation stage, as it negatively affects stress responses. To balance stress tolerance and fermentation performance, we inserted the promoter of a gluconeogenic gene, PCK1, into the 5'-untranslated region (5'-UTR) of the RIM15 gene in a laboratory strain to achieve repression of RIM15 gene expression in the glucose-rich early stage with its induction in the stressful late stage of alcoholic fermentation. The promoter-engineered strain exhibited a fermentation rate comparable to that of the RIM15-deleted strain with no decrease in cell viability. The engineered strain achieved better alcoholic fermentation performance than the RIM15-deleted strain under repetitive and high-glucose fermentation conditions. These data demonstrated the validity of promoter engineering of the RIM15 gene that governs inhibitory control of alcoholic fermentation. Copyright © 2016 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  14. Relationship between fermentation index and other biochemical changes evaluated during the fermentation of Mexican cocoa (Theobroma cacao) beans.

    PubMed

    Romero-Cortes, Teresa; Salgado-Cervantes, Marco Antonio; García-Alamilla, Pedro; García-Alvarado, Miguel Angel; Rodríguez-Jimenes, Guadalupe del C; Hidalgo-Morales, Madeleine; Robles-Olvera, Víctor

    2013-08-15

    During traditional cocoa processing, the end of fermentation is empirically determined by the workers; consequently, a high variability on the quality of fermented cocoa beans is observed. Some physicochemical properties (such as fermentation index) have been used to measure the degree of fermentation and changes in quality, but only after the fermentation process has concluded, using dried cocoa beans. This would suggest that it is necessary to establish a relationship between the chemical changes inside the cocoa bean and the fermentation conditions during the fermentation in order to standardize the process. Cocoa beans were traditionally fermented inside wooden boxes, sampled every 24 h and analyzed to evaluate fermentation changes in complete bean, cotyledon and dried beans. The value of the fermentation index suggested as the minimal adequate (≥1) was observed at 72 h in all bean parts analyzed. At this time, values of pH, spectral absorption, total protein hydrolysis and vicilin-class globulins of fermented beans suggested that they were well fermented. Since no difference was found between the types of samples, the pH value could be used as a first indicator of the end of the fermentation and confirmed by evaluation of the fermentation index using undried samples, during the process. © 2013 Society of Chemical Industry.

  15. Early Neolithic wine of Georgia in the South Caucasus

    PubMed Central

    McGovern, Patrick; Jalabadze, Mindia; Batiuk, Stephen; Callahan, Michael P.; Smith, Karen E.; Hall, Gretchen R.; Kvavadze, Eliso; Maghradze, David; Rusishvili, Nana; Bouby, Laurent; Failla, Osvaldo; Cola, Gabriele; Mariani, Luigi; Boaretto, Elisabetta; Bacilieri, Roberto; This, Patrice; Wales, Nathan; Lordkipanidze, David

    2017-01-01

    Chemical analyses of ancient organic compounds absorbed into the pottery fabrics from sites in Georgia in the South Caucasus region, dating to the early Neolithic period (ca. 6,000–5,000 BC), provide the earliest biomolecular archaeological evidence for grape wine and viniculture from the Near East, at ca. 6,000–5,800 BC. The chemical findings are corroborated by climatic and environmental reconstruction, together with archaeobotanical evidence, including grape pollen, starch, and epidermal remains associated with a jar of similar type and date. The very large-capacity jars, some of the earliest pottery made in the Near East, probably served as combination fermentation, aging, and serving vessels. They are the most numerous pottery type at many sites comprising the so-called “Shulaveri-Shomutepe Culture” of the Neolithic period, which extends into western Azerbaijan and northern Armenia. The discovery of early sixth millennium BC grape wine in this region is crucial to the later history of wine in Europe and the rest of the world. PMID:29133421

  16. Effect of salt-tolerant yeast of Candida versatilis and Zygosaccharomyces rouxii on the production of biogenic amines during soy sauce fermentation.

    PubMed

    Qi, Wei; Hou, Li-Hua; Guo, Hong-Lian; Wang, Chun-Ling; Fan, Zhen-Chuan; Liu, Jin-Fu; Cao, Xiao-Hong

    2014-06-01

    This study aimed to enhance and improve the quality and safety of soy sauce. In the present work, the change of biogenic amines, such as histamine, tyramine, cadaverine, spermidine, was examined by the treatment of Candida versatilis and Zygosaccharomyces rouxii, and the influence of salt-tolerant yeast on biogenic amines was analysed during the whole fermentation process. The results showed that the content of biogenic amines was elevated after yeast treatment and the content of biogenic amines was influenced by using yeast. The dominating biogenic amine in soy sauce was tyramine. At the end of fermentation, the concentrations of biogenic amines produced by Zygosaccharomyces rouxii and Candida versatilis in the soy mash were 122.71 mg kg(-1) and 69.96 mg kg(-1) . The changes of biogenic amines in high-salt liquid soy mash during fermentation process indicated that a variety of biogenic amines were increased in the fermentation ageing period, which may be due to amino acid decarboxylation to form biogenic amines by yeast decarboxylase. The fermentation period of soy sauce should be longer than 5 months because biogenic amines began to decline after this time period. © 2013 Society of Chemical Industry.

  17. Effect of sucrose concentration on the products of Kombucha fermentation on molasses.

    PubMed

    Malbaša, R; Lončar, E; Djurić, M; Došenović, I

    2008-06-01

    Fermentation of 1.5g/l of Indian black tea, sweetened with adequate quantities of molasses (containing approx. 70g/l, 50g/l and 35g/l of sucrose), was conducted using domestic Kombucha. Inoculation was performed with 10% of fermentation broth from a previous process. The fermentation in cylindrical vessels containing 2l of liquid phase, was carried out at 22±1°C for 14 days, with periodical sampling, to measure pH, content of acids (total, acetic and l-lactic), content of remaining sucrose, and the yield of biomass at the end of fermentation. A product with 70g/l sucrose from molasses corresponds to an optimal concentration of carbon source, which provided metabolites with high pH, a low content of less desired acetic acid, a high content of highly desired l-lactic acid, an acceptable content of total acids and the highest possible level of utilisation of sucrose. Copyright © 2007 Elsevier Ltd. All rights reserved.

  18. Metabolomics-based optimal koji fermentation for tyrosinase inhibition supplemented with Astragalus radix.

    PubMed

    Kim, Ah Jin; Choi, Jung Nam; Kim, Jiyoung; Yeo, Soo Hwan; Choi, Ji Ho; Lee, Choong Hwan

    2012-01-01

    The present study was focused on improving the quality of rice koji by fermentation with a selected Aspergillus oryzae strain and a plant Astragalus radix. A. oryzae KCCM 60345 was used as main inoculant and the Astragalus radix was added as supplement in rice koji preparation. LC-MS based metabolite analysis and tyrosinase inhibitory activities were studied for different time periods. A. oryzae KCCM 60345 fermented rice koji supplemented with Astragalus showed higher tyrosinase inhibition activity at 4 d of fermentation and metabolite analysis with PCA and PLS-DA indicated differences in kojic acid, calycosin-7-O-β-D-glucoside, ononin, calycosin, and formononetin as compared with other forms of rice koji fermentation. By correlation analysis between metabolites and tyrosinase inhibitory activity, calycosin and kojic acid were identified as major tyrosinase inhibitors. Based on these results, we concluded that A. oryzae KCCM 60345 supplemented with Astragalus radix is useful for whitening effects, and we identified optimal conditions for rice koji preparation.

  19. [Continuous ethanol fermentation coupled with recycling of yeast flocs].

    PubMed

    Wang, Bo; Ge, Xu-Meng; Li, Ning; Bai, Feng-Wu

    2006-09-01

    A continuous ethanol fermentation system composed of three-stage tanks in series coupled with two sedimentation tanks was established. A self-flocculating yeast strain developed by protoplast fusion from Saccharomyces cerevisiae and Schizosaccharomyces pombe was applied. Two-stage enzymatic hydrolysate of corn powder containing 220g/L of reducing sugar, supplemented with 1.5g/L (NH4)2HPO4 and 2.5g/L KH2PO4, was used as the ethanol fermentation substrate and fed into the first fermentor at the dilution rate of 0.057h(-1). The yeast flocs separated by sedimentation were recycled into the first fermentor as two different models: activation-recycle and direct recycle. The quasi-steady states were obtained for both operation models after the fermentation systems experienced short periods of transitions. Activation process helped enhance the performance of ethanol fermentation at the high dilution rates. The broth containing more than 101g/L ethanol, 3.2g/L residual reducing sugar and 7.7g/L residual total sugar was produced. The ethanol productivity was calculated to be 5.77g/(L x h), which increased by more than 70% compared with that achieved in the same tank in series system without recycling of yeast cells.

  20. [An unexpected stage of alkalosis in the dynamics of the early posthemorrhagic period].

    PubMed

    Beliaev, A V

    2000-01-01

    A study was made on acid-base metabolism in early posthemorrhagic period as exemplified by examination of patients presenting with gastrointestinal hemorrhage. It has been ascertained that hemorrhage is accompanied by a mixed variant of the acid-base state (ABS) deviation, namely metabolic lactate-acidosis and respiratory alkalosis. In the time-related course of posthemorrhagic period such deviations persist in patients with lethal outcome; with the disease running a favourable course the above deviations are found to return to normal quite soon. The development of complications leads to staging in ABC, its stages being as follows: stage I--the initial stage, stage II--persisting metabolic acidosis and respiratory alkalosis, stage III--alkalosis, stage IV--normalization, with stage III of ABS being encouraged by hypocapnia caused by function disorders of the lungs in early posthemorrhagic period, normalization of cell metabolism, increase in the rate of urination as a reflection of the third earlier identified stage of water metabolism, with the H+ excretion in the urine at the previous level. The identified ABS stage III threatens coming trouble, being accompanied by metabolic deviations together with a risk of function disorder of the myocardium.

  1. Detecting cell lysis using viscosity monitoring in E. coli fermentation to prevent product loss.

    PubMed

    Newton, Joseph M; Schofield, Desmond; Vlahopoulou, Joanna; Zhou, Yuhong

    2016-07-08

    Monitoring the physical or chemical properties of cell broths to infer cell status is often challenging due to the complex nature of the broth. Key factors indicative of cell status include cell density, cell viability, product leakage, and DNA release to the fermentation broth. The rapid and accurate prediction of cell status for hosts with intracellular protein products can minimise product loss due to leakage at the onset of cell lysis in fermentation. This article reports the rheological examination of an industrially relevant E. coli fermentation producing antibody fragments (Fab'). Viscosity monitoring showed an increase in viscosity during the exponential phase in relation to the cell density increase, a relatively flat profile in the stationary phase, followed by a rapid increase which correlated well with product loss, DNA release and loss of cell viability. This phenomenon was observed over several fermentations that a 25% increase in broth viscosity (using induction-point viscosity as a reference) indicated 10% product loss. Our results suggest that viscosity can accurately detect cell lysis and product leakage in postinduction cell cultures, and can identify cell lysis earlier than several other common fermentation monitoring techniques. This work demonstrates the utility of rapidly monitoring the physical properties of fermentation broths, and that viscosity monitoring has the potential to be a tool for process development to determine the optimal harvest time and minimise product loss. © 2016 The Authors. Biotechnology Progress published by Wiley Periodicals, Inc. on behalf of American Institute of Chemical Engineers, 32:1069-1076, 2016. © 2016 The Authors. Biotechnology Progress published by Wiley Periodicals, Inc. on behalf of American Institute of Chemical Engineers.

  2. Vacuum packing: a model system for laboratory-scale silage fermentations.

    PubMed

    Johnson, H E; Merry, R J; Davies, D R; Kell, D B; Theodorou, M K; Griffith, G W

    2005-01-01

    To determine the utility of vacuum-packed polythene bags as a convenient, flexible and cost-effective alternative to fixed volume glass vessels for lab-scale silage studies. Using perennial ryegrass or red clover forage, similar fermentations (as assessed by pH measurement) occurred in glass tube and vacuum-packed silos over a 35-day period. As vacuum-packing devices allow modification of initial packing density, the effect of four different settings (initial packing densities of 0.397, 0.435, 0.492 and 0.534 g cm(-3)) on the silage fermentation over 16 days was examined. Significant differences in pH decline and lactate accumulation were observed at different vacuum settings. Gas accumulation was apparent within all bags and changes in bag volume with time was observed to vary according to initial packing density. Vacuum-packed silos do provide a realistic model system for lab-scale silage fermentations. Use of vacuum-packed silos holds potential for lab-scale evaluations of silage fermentations, allowing higher throughput of samples, more consistent packing as well as the possibility of investigating the effects of different initial packing densities and use of different wrapping materials.

  3. Comparison of fermentation of diets of variable composition and microbial populations in the rumen of sheep and Rusitec fermenters. I. Digestibility, fermentation parameters, and microbial growth.

    PubMed

    Martínez, M E; Ranilla, M J; Tejido, M L; Ramos, S; Carro, M D

    2010-08-01

    Four ruminally and duodenally cannulated sheep and 8 Rusitec fermenters were used to determine the effects of forage to concentrate (F:C) ratio and type of forage in the diet on ruminal fermentation and microbial protein synthesis. The purpose of the study was to assess how closely fermenters can mimic the dietary differences found in vivo. The 4 experimental diets contained F:C ratios of 70:30 or 30:70 with either alfalfa hay or grass hay as the forage. Microbial growth was determined in both systems using (15)N as a microbial marker. Rusitec fermenters detected differences between diets similar to those observed in sheep by changing F:C ratio on pH; neutral detergent fiber digestibility; total volatile fatty acid concentrations; molar proportions of acetate, propionate, butyrate, isovalerate, and caproate; and amylase activity. In contrast, Rusitec fermenters did not reproduce the dietary differences found in sheep for NH(3)-N and lactate concentrations, dry matter (DM) digestibility, proportions of isobutyrate and valerate, carboxymethylcellulase and xylanase activities, and microbial growth and its efficiency. Regarding the effect of the type of forage in the diet, Rusitec fermenters detected differences between diets similar to those found in sheep for most determined parameters, with the exception of pH, DM digestibility, butyrate proportion, and carboxymethylcellulase activity. Minimum pH and maximal volatile fatty acid concentrations were reached at 2h and at 6 to 8h postfeeding in sheep and fermenters, respectively, indicating that feed fermentation was slower in fermenters compared with that in sheep. There were differences between systems in the magnitude of most determined parameters. In general, fermenters showed lower lactate concentrations, neutral detergent fiber digestibility, acetate:propionate ratios, and enzymatic activities. On the contrary, fermenters showed greater NH(3)-N concentrations, DM digestibility, and proportions of propionate

  4. Volatile fatty acids productions by mesophilic and thermophilic sludge fermentation: Biological responses to fermentation temperature.

    PubMed

    Hao, Jiuxiao; Wang, Hui

    2015-01-01

    The volatile fatty acids (VFAs) productions, as well as hydrolases activities, microbial communities, and homoacetogens, of mesophilic and thermophilic sludge anaerobic fermentation were investigated to reveal the microbial responses to different fermentation temperatures. Thermophilic fermentation led to 10-fold more accumulation of VFAs compared to mesophilic fermentation. α-glucosidase and protease had much higher activities in thermophilic reactor, especially protease. Illumina sequencing manifested that raising fermentation temperature increased the abundances of Clostridiaceae, Microthrixaceae and Thermotogaceae, which could facilitate either hydrolysis or acidification. Real-time PCR analysis demonstrated that under thermophilic condition the relative abundance of homoacetogens increased in batch tests and reached higher level at stable fermentation, whereas under mesophilic condition it only increased slightly in batch tests. Therefore, higher fermentation temperature increased the activities of key hydrolases, raised the proportions of bacteria involved in hydrolysis and acidification, and promoted the relative abundance of homoacetogens, which all resulted in higher VFAs production. Copyright © 2014 Elsevier Ltd. All rights reserved.

  5. Parents' Views on the Use of Technology in the Early Childhood Period

    ERIC Educational Resources Information Center

    Ekici, Fatma Yasar

    2016-01-01

    The main aim of this research is to examine parents' views on technology use in the early childhood period. Survey method was used in this research. The research population consists of the parents, whose children go to the pre-school education institutions in Istanbul province. The research sample consists of 477 parents chosen by the random…

  6. Lactic acid bacteria involved in cocoa beans fermentation from Ivory Coast: Species diversity and citrate lyase production.

    PubMed

    Ouattara, Hadja D; Ouattara, Honoré G; Droux, Michel; Reverchon, Sylvie; Nasser, William; Niamke, Sébastien L

    2017-09-01

    Microbial fermentation is an indispensable process for high quality chocolate from cocoa bean raw material. lactic acid bacteria (LAB) are among the major microorganisms responsible for cocoa fermentation but their exact role remains to be elucidated. In this study, we analyzed the diversity of LAB in six cocoa producing regions of Ivory Coast. Ribosomal 16S gene sequence analysis showed that Lactobacillus plantarum and Leuconostoc mesenteroides are the dominant LAB species in these six regions. In addition, other species were identified as the minor microbial population, namely Lactobacillus curieae, Enterococcus faecium, Fructobacillus pseudoficulneus, Lactobacillus casei, Weissella paramesenteroides and Weissella cibaria. However, in each region, the LAB microbial population was composed of a restricted number of species (maximum 5 species), which varied between the different regions. LAB implication in the breakdown of citric acid was investigated as a fundamental property for a successful cocoa fermentation process. High citrate lyase producer strains were characterized by rapid citric acid consumption, as revealed by a 4-fold decrease in citric acid concentration in the growth medium within 12h, concomitant with an increase in acetic acid and lactic acid concentration. The production of citrate lyase was strongly dependent on environmental conditions, with optimum production at acidic pH (pH<5), and moderate temperature (30-40°C), which corresponds to conditions prevailing in the early stage of natural cocoa fermentation. This study reveals that one of the major roles of LAB in the cocoa fermentation process involves the breakdown of citric acid during the early stage of cocoa fermentation through the activity of citrate lyase. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. Effects of fermentation substrate conditions on corn-soy co-fermentation for fuel ethanol production.

    PubMed

    Yao, Linxing; Lee, Show-Ling; Wang, Tong; de Moura, Juliana M L N; Johnson, Lawrence A

    2012-09-01

    Soy skim, a protein-rich liquid co-product from the aqueous extraction of soybeans, was co-fermented with corn to produce ethanol. Effects of soy skim addition level, type of skim, corn particle size, water-to-solids ratio, and urea on co-fermentation were determined. The addition of 20-100% skim increased the fermentation rate by 18-27% and shortened the fermentation time by 5-7h without affecting ethanol yield. Finely ground corn or high water-to-solids ratio (≥ 3.0) in the mash gave higher fermentation rates, but did not increase the ethanol yield. When the water was completely replaced with soy skim, the addition of urea became unnecessary. Soy skim retentate that was concentrated by nanofiltration increased fermentation rate by 25%. The highest level of skim addition resulted in a finished beer with 16% solids, 47% protein (dwb) containing 3.6% lysine, and an ethanol yield of 39 g/100g dry corn. Copyright © 2012 Elsevier Ltd. All rights reserved.

  8. Recent advances in electronic nose techniques for monitoring of fermentation process.

    PubMed

    Jiang, Hui; Zhang, Hang; Chen, Quansheng; Mei, Congli; Liu, Guohai

    2015-12-01

    Microbial fermentation process is often sensitive to even slight changes of conditions that may result in unacceptable end-product quality. Thus, the monitoring of the process is critical for discovering unfavorable deviations as early as possible and taking the appropriate measures. However, the use of traditional analytical techniques is often time-consuming and labor-intensive. In this sense, the most effective way of developing rapid, accurate and relatively economical method for quality assurance in microbial fermentation process is the use of novel chemical sensor systems. Electronic nose techniques have particular advantages in non-invasive monitoring of microbial fermentation process. Therefore, in this review, we present an overview of the most important contributions dealing with the quality control in microbial fermentation process using the electronic nose techniques. After a brief description of the fundamentals of the sensor techniques, some examples of potential applications of electronic nose techniques monitoring are provided, including the implementation of control strategies and the combination with other monitoring tools (i.e. sensor fusion). Finally, on the basis of the review, the electronic nose techniques are critically commented, and its strengths and weaknesses being highlighted. In addition, on the basis of the observed trends, we also propose the technical challenges and future outlook for the electronic nose techniques.

  9. High solids fermentation reactor

    DOEpatents

    Wyman, Charles E.; Grohmann, Karel; Himmel, Michael E.; Richard, Christopher J.

    1993-03-02

    A fermentation reactor and method for fermentation of materials having greater than about 10% solids. The reactor includes a rotatable shaft along the central axis, the shaft including rods extending outwardly to mix the materials. The reactor and method are useful for anaerobic digestion of municipal solid wastes to produce methane, for production of commodity chemicals from organic materials, and for microbial fermentation processes.

  10. High solids fermentation reactor

    DOEpatents

    Wyman, Charles E.; Grohmann, Karel; Himmel, Michael E.; Richard, Christopher J.

    1993-01-01

    A fermentation reactor and method for fermentation of materials having greater than about 10% solids. The reactor includes a rotatable shaft along the central axis, the shaft including rods extending outwardly to mix the materials. The reactor and method are useful for anaerobic digestion of municipal solid wastes to produce methane, for production of commodity chemicals from organic materials, and for microbial fermentation processes.

  11. Microbial Succession and Flavor Production in the Fermented Dairy Beverage Kefir

    PubMed Central

    Walsh, Aaron M.; Crispie, Fiona; Kilcawley, Kieran; O’Sullivan, Orla; O’Sullivan, Maurice G.; Claesson, Marcus J.

    2016-01-01

    ABSTRACT Kefir is a putatively health-promoting dairy beverage that is produced when a kefir grain, consisting of a consortium of microorganisms, is added to milk to initiate a natural fermentation. Here, a detailed analysis was carried out to determine how the microbial population, gene content, and flavor of three kefirs from distinct geographic locations change over the course of 24-h fermentations. Metagenomic sequencing revealed that Lactobacillus kefiranofaciens was the dominant bacterial species in kefir during early stages of fermentations but that Leuconostoc mesenteroides became more prevalent in later stages. This pattern is consistent with an observation that genes involved in aromatic amino acid biosynthesis were absent from L. kefiranofaciens but were present in L. mesenteroides. Additionally, these shifts in the microbial community structure, and associated pathways, corresponded to changes in the levels of volatile compounds. Specifically, Acetobacter spp. correlated with acetic acid; Lactobacillus spp. correlated with carboxylic acids, esters and ketones; Leuconostoc spp. correlated with acetic acid and 2,3-butanedione; and Saccharomyces spp. correlated with esters. The correlation data suggest a causal relationship between microbial taxa and flavor that is supported by observations that addition of L. kefiranofaciens NCFB 2797 increased the levels of esters and ketones whereas addition of L. mesenteroides 213M0 increased the levels of acetic acid and 2,3-butanedione. Finally, we detected genes associated with probiotic functionalities in the kefir microbiome. Our results illustrate the dynamic nature of kefir fermentations and microbial succession patterns therein and can be applied to optimize the fermentation processes, flavors, and health-related attributes of this and other fermented foods. IMPORTANCE Traditional fermented foods represent relatively low-complexity microbial environments that can be used as model microbial communities to

  12. Kinetics of D-lactic acid production by Sporolactobacillus sp. strain CASD using repeated batch fermentation.

    PubMed

    Zhao, Bo; Wang, Limin; Li, Fengsong; Hua, Dongliang; Ma, Cuiqing; Ma, Yanhe; Xu, Ping

    2010-08-01

    D-lactic acid was produced by Sporolactobacillus sp. strain CASD in repeated batch fermentation with one- and two-reactor systems. The strain showed relatively high energy consumption in its growth-related metabolism in comparison with other lactic acid producers. When the fermentation was repeated with 10% (v/v) of previous culture to start a new batch, D-lactic acid production shifted from being cell-maintenance-dependent to cell-growth-dependent. In comparison with the one-reactor system, D-lactic acid production increased approximately 9% in the fourth batch of the two-reactor system. Strain CASD is an efficient D-lactic acid producer with increased growth rate at the early stage of repeated cycles, which explains the strain's physiological adaptation to repeated batch culture and improved performance in the two-reactor fermentation system. From a kinetic point of view, two-reactor fermentation system was shown to be an alternative for conventional one-reactor repeated batch operation. Copyright 2010 Elsevier Ltd. All rights reserved.

  13. Sugaring-out extraction of acetoin from fermentation broth by coupling with fermentation.

    PubMed

    Dai, Jian-Ying; Ma, Lin-Hui; Wang, Zhuang-Fei; Guan, Wen-Tian; Xiu, Zhi-Long

    2017-03-01

    Acetoin is a natural flavor and an important bio-based chemical which could be separated from fermentation broth by solvent extraction, salting-out extraction or recovered in the form of derivatives. In this work, a novel method named as sugaring-out extraction coupled with fermentation was tried in the acetoin production by Bacillus subtilis DL01. The effects of six solvents on bacterial growth and the distribution of acetoin and glucose in different solvent-glucose systems were explored. The operation parameters such as standing time, glucose concentration, and volume ratio of ethyl acetate to fermentation broth were determined. In a system composed of fermentation broth, glucose (100%, m/v) and two-fold volume of ethyl acetate, nearly 100% glucose was distributed into bottom phase, and 61.2% acetoin into top phase without coloring matters and organic acids. The top phase was treated by vacuum distillation to remove solvent and purify acetoin, while the bottom phase was used as carbon source to produce acetoin in the next batch of fermentation.

  14. Early and late hot extremes, and elongation of the warm period over Greece

    NASA Astrophysics Data System (ADS)

    Founda, Dimitra; Giannakopoulos, Christos; Pierros, Fragiskos

    2017-04-01

    The eastern Mediterranean has been assigned as one of the most responsive areas in climate change, mainly with respect to the occurrence of warmer and drier conditions. In Greece in particular, observations suggest prominent increases in the summer air temperature which in some areas amount to approximately 1 0C/decade since the mid 1970s, while Regional Climate Models simulate further increases in the near and distant future. These changes are coupled with simultaneous increase in the occurrence of hot extremes. In addition to changes in the frequency and intensity of hot extrems, timing of occurrence is also of special interest. Early heat waves in particular, have been found to increase thermal risk in humans. The study explores variations and trends in timing, namely the date of first and last occurrence of hot extremes within the year, and subsequently the hot extremes period (season), defined as the time interval (number of days) between first and last hot extremes occurrence, over Greece. A case study for the area of Athens covering a longer than 100-years period (1897-2015) was conducted first, which will be extended to other Greek areas. Several heat related climatic indices were used, based either on predefined temperature thresholds such as 'tropical days' (daily maximum air temperature, Tmax >30 0C), 'tropical nights' (daily minimum air temperature, Tmin >20 0C), 'hot days' (Tmax >35 0C), or on local climate statistics such as days with Tmax (or Tmin) > 95th percentile. The analysis revealed significant changes in the period of hot extremes and specifically elongation of the period, attributed to early rather than late hot extremes occurrence. An earlier shift of the first tropical day and the first tropical night occurrence by approximately 2 days/decade was found over the study period. An overall elongation of the 'hot days' season by 2.6 days/decade was also observed, which is more prominent since the early 1980s. Over the last three decades, earlier

  15. Effect of cultivating conditions on alpha-galactosidase production by a novel Aspergillus foetidus ZU-G1 strain in solid-state fermentation.

    PubMed

    Liu, Cai-qin; Chen, Qi-he; Cheng, Qian-jun; Wang, Jin-ling; He, Guo-qing

    2007-05-01

    The work is intended to achieve optimum culture conditions of alpha-galactosidase production by a mutant strain Aspergillus foetidus ZU-G1 in solid-state fermentation (SSF). Certain fermentation parameters involving moisture content, incubation temperature, cultivation period of seed, inoculum volume, initial pH value, layers of pledget, load size of medium and period of cultivation were investigated separately. The optimal cultivating conditions of alpha-galactosidase production in SSF were 60% initial moisture of medium, 28 degrees C incubation temperature, 18 h cultivation period of seed, 10% inoculum volume, 5.0 approximately 6.0 initial pH of medium, 6 layers of pledget and 10 g dry matter loadage. Under the optimized cultivation conditions, the maximum alpha-galactosidase production was 2 037.51 U/g dry matter near the 144th hour of fermentation.

  16. Effect of cultivating conditions on α-galactosidase production by a novel Aspergillus foetidus ZU-G1 strain in solid-state fermentation

    PubMed Central

    Liu, Cai-qin; Chen, Qi-he; Cheng, Qian-jun; Wang, Jin-ling; He, Guo-qing

    2007-01-01

    The work is intended to achieve optimum culture conditions of α-galactosidase production by a mutant strain Aspergillus foetidus ZU-G1 in solid-state fermentation (SSF). Certain fermentation parameters involving moisture content, incubation temperature, cultivation period of seed, inoculum volume, initial pH value, layers of pledget, load size of medium and period of cultivation were investigated separately. The optimal cultivating conditions of α-galactosidase production in SSF were 60% initial moisture of medium, 28 °C incubation temperature, 18 h cultivation period of seed, 10% inoculum volume, 5.0~6.0 initial pH of medium, 6 layers of pledget and 10 g dry matter loadage. Under the optimized cultivation conditions, the maximum α-galactosidase production was 2 037.51 U/g dry matter near the 144th hour of fermentation. PMID:17542067

  17. Schedules for home visits in the early postpartum period.

    PubMed

    Yonemoto, Naohiro; Dowswell, Therese; Nagai, Shuko; Mori, Rintaro

    2017-08-02

    Maternal complications including psychological and mental health problems and neonatal morbidity have been commonly observed in the postpartum period. Home visits by health professionals or lay supporters in the weeks following the birth may prevent health problems from becoming chronic with long-term effects on women, their babies, and their families. To assess outcomes for women and babies of different home-visiting schedules during the early postpartum period. The review focuses on the frequency of home visits, the duration (when visits ended) and intensity, and on different types of home-visiting interventions. We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (28 January 2013) and reference lists of retrieved articles. Randomised controlled trials (RCTs) (including cluster-RCTs) comparing different types of home-visiting interventions enrolling participants in the early postpartum period (up to 42 days after birth). We excluded studies in which women were enrolled and received an intervention during the antenatal period (even if the intervention continued into the postnatal period) and studies recruiting only women from specific high-risk groups. (e.g. women with alcohol or drug problems). Study eligibility was assessed by at least two review authors. Data extraction and assessment of risk of bias were carried out independently by at least two review authors. Data were entered into Review Manager software. We included data from 12 randomised trials with data for more than 11,000 women. The trials were carried out in countries across the world, and in both high- and low-resource settings. In low-resource settings women receiving usual care may have received no additional postnatal care after early hospital discharge.The interventions and control conditions varied considerably across studies with trials focusing on three broad types of comparisons: schedules involving more versus fewer postnatal home visits (five studies), schedules

  18. Effects of protectant and rehydration conditions on the survival rate and malolactic fermentation efficiency of freeze-dried Lactobacillus plantarum JH287.

    PubMed

    Lee, Sae-Byuk; Kim, Dong-Hwan; Park, Heui-Dong

    2016-09-01

    In this study, Lactobacillus plantarum JH287 was used as a malolactic fermentation starter in Campbell Early wine production. L. plantarum JH287 was first lyophilized, and the malolactic fermentation potential of freeze-dried L. plantarum JH287 was investigated. Different protective media and rehydration conditions were tested to improve the survival rate of freeze-dried L. plantarum JH287. Optimal protective medium contained 10 % sorbitol and 10 % skim milk. The optimal rehydration condition was a 1-h rehydration time conducted in the same protective media, and the combination of these two methods produced a survival rate of 86.37 %. In addition, a 77.71 % survival rate was achieved using freeze-dried samples that were stored at 4 °C for 2 months. Freeze-dried L. plantarum JH287 and Saccharomyces cerevisiae Fermivin were used to inoculate the Campbell Early grape must to decrease its malic acid content. Using this mixed-fermentation method, wine showed a decrease in malic acid content after 9 days of fermentation. GC-MS analysis detected 15 volatile ester compounds in the wine. A sensory evaluation showed that the taste and aroma of mix-fermented wine were better than those of the control that had not been inoculated with L. plantarum JH287.

  19. An Early Sensitive Period Induces Long-Lasting Plasticity in the Honeybee Nervous System

    PubMed Central

    Grosso, Juan P.; Barneto, Jesica A.; Velarde, Rodrigo A.; Pagano, Eduardo A.; Zavala, Jorge A.; Farina, Walter M.

    2018-01-01

    The effect of early experiences on the brain during a sensitive period exerts a long-lasting influence on the mature individual. Despite behavioral and neural plasticity caused by early experiences having been reported in the honeybee Apis mellifera, the presence of a sensitive period in which associative experiences lead to pronounced modifications in the adult nervous system is still unclear. Laboratory-reared bees were fed with scented food within specific temporal windows and were assessed for memory retention, in the regulation of gene expression related to the synaptic formation and in the olfactory perception of their antennae at 17 days of age. Bees were able to retain a food-odor association acquired 5–8 days after emergence, but not before, and showed better retention than those exposed to an odor at 9–12 days. In the brain, the odor-rewarded experiences that occurred at 5–8 days of age boosted the expression levels of the cell adhesion proteins neurexin 1 (Nrx1) and neuroligin 2 (Nlg2) involved in synaptic strength. At the antennae, the experiences increased the electrical response to a novel odor but not to the one experienced. Therefore, a sensitive period that induces long-lasting behavioral, functional and structural changes is found in adult honeybees. PMID:29449804

  20. An Early Sensitive Period Induces Long-Lasting Plasticity in the Honeybee Nervous System.

    PubMed

    Grosso, Juan P; Barneto, Jesica A; Velarde, Rodrigo A; Pagano, Eduardo A; Zavala, Jorge A; Farina, Walter M

    2018-01-01

    The effect of early experiences on the brain during a sensitive period exerts a long-lasting influence on the mature individual. Despite behavioral and neural plasticity caused by early experiences having been reported in the honeybee Apis mellifera , the presence of a sensitive period in which associative experiences lead to pronounced modifications in the adult nervous system is still unclear. Laboratory-reared bees were fed with scented food within specific temporal windows and were assessed for memory retention, in the regulation of gene expression related to the synaptic formation and in the olfactory perception of their antennae at 17 days of age. Bees were able to retain a food-odor association acquired 5-8 days after emergence, but not before, and showed better retention than those exposed to an odor at 9-12 days. In the brain, the odor-rewarded experiences that occurred at 5-8 days of age boosted the expression levels of the cell adhesion proteins neurexin 1 ( Nrx1 ) and neuroligin 2 ( Nlg2 ) involved in synaptic strength. At the antennae, the experiences increased the electrical response to a novel odor but not to the one experienced. Therefore, a sensitive period that induces long-lasting behavioral, functional and structural changes is found in adult honeybees.

  1. Acclimation of peanut (Arachis hypogaea L.) to water stress through exposure to differing periods of early season drought

    USDA-ARS?s Scientific Manuscript database

    Peanut (Arachis hypogaea L.) is able to withstand periods of water scarcity either in the early or late periods of the growing season, but suffers significant stress and yield loss during drought periods in mid-season, or the period coinciding with peak flower production and pod maturation. In fact...

  2. Antioxidative probiotic fermented goats' milk decreases oxidative stress-mediated atherogenicity in human subjects.

    PubMed

    Kullisaar, Tiiu; Songisepp, Epp; Mikelsaar, Marika; Zilmer, Kersti; Vihalemm, Tiiu; Zilmer, Mihkel

    2003-08-01

    The increasing interest in a healthy diet is stimulating innovative development of novel scientific products in the food industry. The viable lactic acid bacteria in fermented milk products, such as yoghurt, have been associated with increased lactose tolerance, a well-balanced intestinal microflora, antimicrobial activity, stimulation of the immune system and antitumoural, anticholesterolaemic and antioxidative properties in human subjects. Recently, we have studied a human Lactobacillus spp. strain that possesses antioxidative activity. The aim of the present pilot study was to develop goats' milk fermented with the human antioxidative lactobacilli strain, Lactobacillus fermentum ME-3, and to test the effect of the fermented probiotic goats' milk on oxidative stress markers (including markers for atherosclerosis) in human blood and urine and on the gut microflora. Twenty-one healthy subjects were assigned to two treatment groups: goats' milk group and fermented goats' milk group (150 g/d) for a period of 21 d. Consumption of fermented goats' milk improved anti-atherogenicity in healthy subjects: it prolonged resistance of the lipoprotein fraction to oxidation, lowered levels of peroxidized lipoproteins, oxidized LDL, 8-isoprostanes and glutathione redox ratio, and enhanced total antioxidative activity. The consumption of fermented goats' milk also altered both the prevalence and proportion of lactic acid bacteria species in the gut microflora of the subjects. We conclude that the goats' milk fermented with our special antioxidative lactobacilli strain Lactobacillus fermentum ME-3 exhibits anti-atherogenic effects.

  3. 27 CFR 24.197 - Production by fermentation.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2014-04-01 2014-04-01 false Production by fermentation... fermentation. In producing special natural wine by fermentation, flavoring materials may be added before or during fermentation. Special natural wine produced by fermentation may be ameliorated in the same manner...

  4. 27 CFR 24.197 - Production by fermentation.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2013-04-01 2013-04-01 false Production by fermentation... fermentation. In producing special natural wine by fermentation, flavoring materials may be added before or during fermentation. Special natural wine produced by fermentation may be ameliorated in the same manner...

  5. 27 CFR 24.197 - Production by fermentation.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2012-04-01 2012-04-01 false Production by fermentation... fermentation. In producing special natural wine by fermentation, flavoring materials may be added before or during fermentation. Special natural wine produced by fermentation may be ameliorated in the same manner...

  6. 27 CFR 24.197 - Production by fermentation.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2011-04-01 2011-04-01 false Production by fermentation... fermentation. In producing special natural wine by fermentation, flavoring materials may be added before or during fermentation. Special natural wine produced by fermentation may be ameliorated in the same manner...

  7. 27 CFR 24.197 - Production by fermentation.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Production by fermentation... fermentation. In producing special natural wine by fermentation, flavoring materials may be added before or during fermentation. Special natural wine produced by fermentation may be ameliorated in the same manner...

  8. Improved fermentation performance in an expanded ectopic fermentation system inoculated with thermophilic bacteria.

    PubMed

    Guo, Hui; Zhu, Changxiong; Geng, Bing; Liu, Xue; Ye, Jing; Tian, Yunlong; Peng, Xiawei

    2015-12-01

    Previous research showed that ectopic fermentation system (EFS) inoculated with thermophilic bacteria is an excellent alternative for cow wastewater treatment. In this study, the effects of thermophilic bacterial consortium on the efficiency and quality of the fermentation process in EFS were evaluated by measuring physicochemical and environmental factors and the changes in organic matter composition. In parallel, the microbial communities correlated with fermentation performance were identified. Inoculation of EFS with thermophilic bacterial consortium led to higher temperatures, increased wastewater requirements for continuous fermentation, and improved quality of the litters in terms of physicochemical factors, security test, functional group analysis, and bacterial community composition. The relationship between the transformation of organic component and the dominant bacteria species indicated that environmental factors contributed to strain growth, which subsequently promoted the fermentation process. The results highlight the great potential of EFS model for wide application in cow wastewater treatment and re-utilization as bio-fertilizer. Copyright © 2015 Elsevier Ltd. All rights reserved.

  9. Microbiological and physicochemical analysis of pumpkin juice fermentation by the basidiomycetous fungus Ganoderma lucidum.

    PubMed

    Zhao, Jing; Liu, Wei; Chen, Dong; Zhou, Chunli; Song, Yi; Zhang, Yuyu; Ni, Yuanying; Li, Quanhong

    2015-02-01

    A new protocol for processing of pumpkin juice was set up which included fermentation by the basidiomycete Ganoderma lucidum at 28 °C for 7 d. The growth curve of G. lucidum in pumpkin juice was successfully (R(2)  = 0.99) fitted by a 4-parameter logistic model and the ideal highest biomass was estimated to be 4.79 g/L. G. lucidum was found to have a significant acidification effect on pumpkin juice. The lowest pH (4.05 ± 0.05) and highest total titratable acidity (14.31 ± 0.16 mL 0.1 M NaOH/100 mL) were found on the 4th day during fermentation. Sugars in pumpkin juice fermented with G. lucidum showed a significant decrease, especially glucose and fructose. On the contrary, the release of exo-polysaccharides and free amino acids greatly enriched the pumpkin juice. The variation of color index and viscosity also mirrored the above behavior. Based on headspace solid phase microextraction and gas chromatography-mass spectrometry, 68 volatile compounds were identified, including 17 esters, 14 alcohols, 13 phenyl compounds, 11 aldehydes, 8 ketones, 3 acids, 1 furan, and 1 benzothiazole. The pumpkin juices fermented for different days were markedly differentiated with principal component analysis and the fermentation process was tentatively divided into 3 periods: the booming (from the 1st to 4th day), steady (from the 5th to 6th day), and decline (the 7th day) period. © 2014 Institute of Food Technologists®

  10. Ferment in Technology

    ERIC Educational Resources Information Center

    Crossland, Janice

    1974-01-01

    A pollution-reducing and energy-saving alternative to petroleum use could be the fermentation industry and other technologies based on the use of renewable resources. Expansion of the fermentation industry could reduce our dependence on petroleum, reduce growing waste disposal problems, and help solve world food shortages. (BT)

  11. Analytical solution of Luedeking-Piret equation for a batch fermentation obeying Monod growth kinetics.

    PubMed

    Garnier, Alain; Gaillet, Bruno

    2015-12-01

    Not so many fermentation mathematical models allow analytical solutions of batch process dynamics. The most widely used is the combination of the logistic microbial growth kinetics with Luedeking-Piret bioproduct synthesis relation. However, the logistic equation is principally based on formalistic similarities and only fits a limited range of fermentation types. In this article, we have developed an analytical solution for the combination of Monod growth kinetics with Luedeking-Piret relation, which can be identified by linear regression and used to simulate batch fermentation evolution. Two classical examples are used to show the quality of fit and the simplicity of the method proposed. A solution for the combination of Haldane substrate-limited growth model combined with Luedeking-Piret relation is also provided. These models could prove useful for the analysis of fermentation data in industry as well as academia. © 2015 Wiley Periodicals, Inc.

  12. Fermentative preparation of functional drink from Punica granatum using lactic acid bacteria and exploring its anti-tumor potential

    NASA Astrophysics Data System (ADS)

    Murthy, Shruthi N.; Patnaik, Amie; Srinivasan, Nandini; Selvarajan, E.; Nivetha, A.; Mohanasrinivasan, V.

    2017-11-01

    In the present research work probiotic pomegranate juice production by fermentation was carried out using two different strains such as Lactobacillus plantarum VITES07 and Lactobacillus acidophilus NCIM2903 (Lactic acid bacteria). Fermented pomegranate juice was carried out at room temperature for 72h. During the fermentation period at regular intervals viable cells was determined. Efficiency of the fermented juice was analysed for 4 weeks under refrigerated condition at 4˚C. Total phenolics, sugar concentration, antioxidant potential, and antibacterial activity were determined. Organic acid concentration was determined by HPLC with retention time of a compound at 9.1 can be suspected to be Kaempferol hexoside and functional group was determined by FTIR also LCMS analysis was carried out to enumerate the chemical composition of the fermented juice.

  13. Fermentation of philippine vegetable blends.

    PubMed

    Orillo, C A; Sison, E C; Luis, M; Pederson, C S

    1969-01-01

    Seven blends of Philipphine vegetables, two of which contained soybeans and one mongo bean sprouts, were prepared for fermentation and study of microbiological and chemical changes. The fermentations were typical lactic acid bacterial fermentations, initiated by Leuconostoc mesenteroides and continued by Lactobacillus brevis, Pediococcus cerevisiae, and L. plantarum. The combination of high acidity and low pH resembled other vegetable fermentations, such as sauerkraut. The procedure offers a method of preserving surplus vegetables, and, in addition, a method for incorporating and preserving the high-protein-containing soybeans.

  14. Fermentative alcohol production

    DOEpatents

    Wilke, Charles R.; Maiorella, Brian L.; Blanch, Harvey W.; Cysewski, Gerald R.

    1982-01-01

    An improved fermentation process for producing alcohol which includes the combination of vacuum fermentation and vacuum distillation. Preferably, the vacuum distillation is carried out in two phases, one a fermentor proper operated at atmospheric pressure and a flash phase operated at reduced pressure with recycle of fermentation brew having a reduced alcohol content to the fermentor, using vapor recompression heating of the flash-pot recycle stream to heat the flash-pot or the distillation step, and using "water load balancing" (i.e., the molar ratio of water in the fermentor feed is the same as the molar ratio of water in the distillation overhead).

  15. Monitoring of Yeast Communities and Volatile Flavor Changes During Traditional Korean Soy Sauce Fermentation.

    PubMed

    Song, Young-Ran; Jeong, Do-Youn; Baik, Sang-Ho

    2015-09-01

    Flavor development in soy sauce is significantly related to the diversity of yeast species. Due to its unique fermentation with meju, the process of making Korean soy sauce gives rise to a specific yeast community and, therefore, flavor profile; however, no detailed analysis of the identifying these structure has been performed. Changes in yeast community structure during Korean soy sauce fermentation were examined using both culture-dependent and culture-independent methods with simultaneous analysis of the changes in volatile compounds by GC-MS analysis. During fermentation, Candida, Pichia, and Rhodotorula sp. were the dominant species, whereas Debaryomyces, Torulaspora, and Zygosaccharomyces sp. were detected only at the early stage. In addition, Cryptococcus, Microbotryum, Tetrapisispora, and Wickerhamomyces were detected as minor strains. Among the 62 compounds identified in this study, alcohols, ketones, and pyrazines were present as the major groups during the initial stages, whereas the abundance of acids with aldehydes increased as the fermentation progressed. Finally, the impacts of 10 different yeast strains found to participate in fermentation on the formation of volatile compounds were evaluated under soy-based conditions. It was revealed that specific species produced different profiles of volatile compounds, some of which were significant flavor contributors, especially volatile alcohols, aldehydes, esters, and ketones. © 2015 Institute of Food Technologists®

  16. Thrombolysis with intravenous recombinant tissue plasminogen activator during early postpartum period: a review of the literature.

    PubMed

    Akazawa, Munetoshi; Nishida, Makoto

    2017-05-01

    Thromboembolic events are one of the leading causes of maternal death during the postpartum period. Postpartum thrombolytic therapy with recombinant tissue plasminogen activator (rt-PA) is controversial because the treatment may lead to massive bleeding. Data centralization may be beneficial for analyzing the safety and effectiveness of systemic thrombolysis during the early postpartum period. We performed a computerized MEDLINE and EMBASE search. We collected data for 13 cases of systemic thrombolytic therapy during the early postpartum period, when limiting the early postpartum period to 48 hours after delivery. Blood transfusion was necessary in all cases except for one (12/13; 92%). In seven cases (7/13; 54%), a large amount of blood was required for transfusion. Subsequent laparotomy to control bleeding was required in five cases (5/13; 38%), including three cases of hysterectomy and two cases of hematoma removal, all of which involved cesarean delivery. In cases of transvaginal delivery, there was no report of laparotomy. The occurrence of severe bleeding was high in relation to cesarean section, compared with vaginal deliveries. Using rt-PA in relation to cesarean section might be worth avoiding. However, the paucity of data in the literature makes it difficult to assess the ultimate outcomes and safety of this treatment. © 2017 Nordic Federation of Societies of Obstetrics and Gynecology.

  17. Temporal trends of latency period and perinatal survival after very early preterm premature rupture of fetal membranes.

    PubMed

    González-Mesa, Ernesto; Herrera, José A; Urgal, Amaya; Lazarraga, Cristina; Benítez, María J; Gómez, Cristina

    2012-08-01

    This paper shows temporal trends of latency period and perinatal survival after preterm premature rupture of membranes at or before 28 weeks (very early PPROM). We have studied retrospectively medical records of all cases of very early PPROM attended in our Obstetric Department from January 1, 2000 to December 31, 2010. A total of 327 cases of very early PPROM were attended, representing 0.4 % of all deliveries, 3.68 % of all preterm births and 15 % of cases all of PPROM. The mean gestational age at delivery was 27 weeks (range 20-34). The mean duration of latency period for the total of 327 cases was 12.1 days (range 0-83, SD 13.3), with a clear trend to its increase from 2005 (p < 0.05). The mean duration of latency period was largest in 2010 (p < 0.05). For the whole period 2000-2010, perinatal deaths reached 30.6 % of all cases, with a clear trend to decrease as gestational age at diagnosis increased, and over the years of study. We have also found a high rate of obstetric complications and a high rate of cesarean deliveries. The upward trend in the duration of latency period in all groups over the years of study and the encouraging perinatal survival observed, even in previable PPROM, are incentives to follow expectant/conservative management in these cases.

  18. Xylose fermentation to ethanol

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    McMillan, J.D.

    1993-01-01

    The past several years have seen tremendous progress in the understanding of xylose metabolism and in the identification, characterization, and development of strains with improved xylose fermentation characteristics. A survey of the numerous microorganisms capable of directly fermenting xylose to ethanol indicates that wild-type yeast and recombinant bacteria offer the best overall performance in terms of high yield, final ethanol concentration, and volumetric productivity. The best performing bacteria, yeast, and fungi can achieve yields greater than 0.4 g/g and final ethanol concentrations approaching 5%. Productivities remain low for most yeast and particularly for fungi, but volumetric productivities exceeding 1.0 g/L-hmore » have been reported for xylose-fermenting bacteria. In terms of wild-type microorganisms, strains of the yeast Pichia stipitis show the most promise in the short term for direct high-yield fermentation of xylose without byproduct formation. Of the recombinant xylose-fermenting microorganisms developed, recombinant E. coli ATTC 11303 (pLOI297) exhibits the most favorable performance characteristics reported to date.« less

  19. Vibration-induced particle formation during yogurt fermentation - Industrial vibration measurements and development of an experimental setup.

    PubMed

    Körzendörfer, Adrian; Temme, Philipp; Nöbel, Stefan; Schlücker, Eberhard; Hinrichs, Jörg

    2016-07-01

    The aim of the study was to investigate the effects of vibrations during yogurt fermentation. Machinery such as pumps and switching valves generate vibrations that may disturb the gelation by inducing large particles. Oscillation measurements on an industrial yogurt production line showed that oscillations are transferred from pumps right up to the fermentation tanks. An experimental setup (20L) was developed to study the effect of vibrations systematically. The fermenters were decoupled with air springs to enable reference fermentations under idle conditions. A vibration exciter was used to stimulate the fermenters. Frequency sweeps (25-1005Hz, periodic time 10s) for 20min from pH5.4 induced large particles. The number of visible particles was significantly increased from 35±4 (reference) to 89±9 particles per 100g yogurt. Rheological parameters of the stirred yogurt samples were not influenced by vibrations. Copyright © 2016 Elsevier Ltd. All rights reserved.

  20. Application of autochthonous mixed starter for controlled Kedong sufu fermentation in pilot plant tests.

    PubMed

    Feng, Zhen; Xu, Miao; Zhai, Shuang; Chen, Hong; Li, Ai-li; Lv, Xin-tong; Deng, Hong-ling

    2015-01-01

    Traditional sufu is fermented by back-slopping and back-slopping has many defects. The objective of this study was to apply autochthonous mixed starter to control Kedong sufu fermentation. Sufu was manufactured using back-slopping (batch A) and autochthonous mixed starter (batch B) with Kocuria kristinae F7, Micrococcus luteus KDF1, and Staphylococcus carnosus KDFR1676. Considering physicochemical properties of sufu, 150-day sufu samples from batch A and 90-day sufu samples from batch B met the standard requirements, respectively. Considering sensory characteristics of sufu, 150-day sufu samples from batch A and 90-day sufu samples from batch B showed no significant differences (P > 0.05). The maturation period of sufu was shortened by 60 d. Profiles of free amino acids and peptides partly revealed the mechanism of typical sensory quality and shorter ripening time of sufu manufactured by autochthonous mixed starter. In final products, content of total biogenic amines was reduced by 48%. Autochthonous mixed starter performed better than back-slopping. Fermentation had a positive influence on the quality, safety, and sensory properties of sufu. The application of autochthonous mixed starter does not change the sensory characteristics of traditional fermented sufu. In addition, it reduces maturation period and improves their homogeneity and safety. It is possible to substitute autochthonous mixed starter for back-slopping in the manufacture of sufu. © 2014 Institute of Food Technologists®

  1. Detailed analysis of the microbial population in Malaysian spontaneous cocoa pulp fermentations reveals a core and variable microbiota.

    PubMed

    Meersman, Esther; Steensels, Jan; Mathawan, Melissa; Wittocx, Pieter-Jan; Saels, Veerle; Struyf, Nore; Bernaert, Herwig; Vrancken, Gino; Verstrepen, Kevin J

    2013-01-01

    The fermentation of cocoa pulp is one of the few remaining large-scale spontaneous microbial processes in today's food industry. The microbiota involved in cocoa pulp fermentations is complex and variable, which leads to inconsistent production efficiency and cocoa quality. Despite intensive research in the field, a detailed and comprehensive analysis of the microbiota is still lacking, especially for the expanding Asian production region. Here, we report a large-scale, comprehensive analysis of four spontaneous Malaysian cocoa pulp fermentations across two time points in the harvest season and two fermentation methods. Our results show that the cocoa microbiota consists of a "core" and a "variable" part. The bacterial populations show a remarkable consistency, with only two dominant species, Lactobacillus fermentum and Acetobacter pasteurianus. The fungal diversity is much larger, with four dominant species occurring in all fermentations ("core" yeasts), and a large number of yeasts that only occur in lower numbers and specific fermentations ("variable" yeasts). Despite this diversity, a clear pattern emerges, with early dominance of apiculate yeasts and late dominance of Saccharomyces cerevisiae. Our results provide new insights into the microbial diversity in Malaysian cocoa pulp fermentations and pave the way for the selection of starter cultures to increase efficiency and consistency.

  2. Detailed Analysis of the Microbial Population in Malaysian Spontaneous Cocoa Pulp Fermentations Reveals a Core and Variable Microbiota

    PubMed Central

    Mathawan, Melissa; Wittocx, Pieter-Jan; Saels, Veerle; Struyf, Nore; Bernaert, Herwig; Vrancken, Gino; Verstrepen, Kevin J.

    2013-01-01

    The fermentation of cocoa pulp is one of the few remaining large-scale spontaneous microbial processes in today's food industry. The microbiota involved in cocoa pulp fermentations is complex and variable, which leads to inconsistent production efficiency and cocoa quality. Despite intensive research in the field, a detailed and comprehensive analysis of the microbiota is still lacking, especially for the expanding Asian production region. Here, we report a large-scale, comprehensive analysis of four spontaneous Malaysian cocoa pulp fermentations across two time points in the harvest season and two fermentation methods. Our results show that the cocoa microbiota consists of a “core” and a “variable” part. The bacterial populations show a remarkable consistency, with only two dominant species, Lactobacillus fermentum and Acetobacter pasteurianus. The fungal diversity is much larger, with four dominant species occurring in all fermentations (“core” yeasts), and a large number of yeasts that only occur in lower numbers and specific fermentations (“variable” yeasts). Despite this diversity, a clear pattern emerges, with early dominance of apiculate yeasts and late dominance of Saccharomyces cerevisiae. Our results provide new insights into the microbial diversity in Malaysian cocoa pulp fermentations and pave the way for the selection of starter cultures to increase efficiency and consistency. PMID:24358116

  3. Serum and saliva cortisol relations in adolescents during pregnancy and the early postpartum period.

    PubMed

    Dorn, L D; Susman, E J

    1993-08-15

    The purpose of this investigation was to examine: (1) relations between serum and saliva cortisol in adolescents in pregnancy and early postpartum and (2) short-term consistency of serum and saliva cortisol across three samples, 20 minutes apart, as well as the long-term consistency from pregnancy to early postpartum. Pregnant adolescents (n = 40), ages 14 to 19 years, were enrolled in this study. Subjects were seen at 20 weeks gestation or earlier (T1), 34-36 weeks gestation (T2), and 2-3 weeks postpartum (T3). Blood samples were drawn at T1 and T3, at 0, 20, and 40 minutes. Saliva samples were collected across the same 40-minute period at T1, T2, and T3. Spearman rho (rs) correlation coefficients between serum and saliva ranged from 0.72 to 0.77 (T1), and 0.42 to 0.60 (T3) (p < or = 0.05). Short-term consistency between serum cortisol samples was 0.86-0.97 at T1 and 0.60-0.82 at T3. Short-term consistency for saliva cortisol samples was 0.70-0.96 at T1, 0.91-0.95 at T2, and 0.64-0.89 at T3. Long-term consistency (T1 to T3) for serum and saliva cortisol was low. Individual differences as well as dramatic changes in the endocrine environment in pregnancy and the early postpartum period may explain the more moderate serum-saliva correlations in the postpartum period.

  4. Design of a lamella settler for biomass recycling in continuous ethanol fermentation process.

    PubMed

    Tabera, J; Iznaola, M A

    1989-04-20

    The design and application of a settler to a continuous fermentation process with yeast recycle were studied. The compact lamella-type settler was chosen to avoid large volumes associated with conventional settling tanks. A rationale of the design method is covered. The sedimentation area was determined by classical batch settling rate tests and sedimentation capacity calculation. Limitations on the residence time of the microorganisms in the settler, rather than sludge thickening considerations, was the approach employed for volume calculation. Fermentation rate tests with yeast after different sedimentation periods were carried out to define a suitable residence time. Continuous cell recycle fermentation runs, performed with the old and new sedimentation devices, show that lamella settler improves biomass recycling efficiency, being the process able to operate at higher sugar concentrations and faster dilution rates.

  5. COMPARISON OF GESTATIONAL AGE AT DELIVERY BASED ON LAST MENSTRUAL PERIOD AND EARLY ULTRASOUND

    EPA Science Inventory

    Reported date of last menstrual period (LMP) is commonly used to estimate gestational age but may be unreliable if recall is inaccurate or time between menstruation and ovulation differs from the presumed 15-day interval. Early ultrasound is generally a more accurate method than ...

  6. Recombinant Zymomonas for pentose fermentation

    DOEpatents

    Picataggio, S.K.; Min Zhang; Eddy, C.K.; Deanda, K.A.

    1998-03-10

    The invention relates to microorganisms which normally do not ferment pentose sugar and which are genetically altered to ferment pentose sugar to produce ethanol, and fermentation processes utilizing the same. Examples include Zymomonas mobilis which has been transformed with combinations of E. coli genes for xylose isomerase, xylulokinase, transaldolase, transketolase, L-arabinose isomerase, L-ribulokinase, and L-ribulose-5-phosphate 4-epimerase. Expression of the added genes are under the control of Zymomonas mobilis promoters. These newly created microorganisms are useful for fermenting pentoses and glucose, produced by hydrolysis of hemicellulose and cellulose, to produce ethanol. 7 figs.

  7. Pentose fermentation by recombinant Zymomonas

    DOEpatents

    Picataggio, S.K.; Zhang, M.; Eddy, C.K.; Deanda, K.A.; Finkelstein, M.; Mohagheghi, A.; Newman, M.M.; McMillan, J.D.

    1998-01-27

    The invention relates to microorganisms which normally do not ferment pentose sugar and which are genetically altered to ferment pentose sugar to produce ethanol, and fermentation processes utilizing the same. Examples include Zymomonas mobilis which has been transformed with combinations of E. coli genes for xylose isomerase, xylulokinase, transaldolase, transketolase, L-arabinose isomerase, L-ribulokinase, and L-ribulose 5-phosphate 4-epimerase. Expression of the added genes are under the control of Zymomonas mobilis promoters. These newly created microorganisms are useful for fermenting pentoses and glucose, produced by hydrolysis of hemicellulose and cellulose, to produce ethanol. 7 figs.

  8. Pentose fermentation by recombinant zymomonas

    DOEpatents

    Picataggio, Stephen K.; Zhang, Min; Eddy, Christina K.; Deanda, Kristine A.; Finkelstein, Mark; Mohagheghi, Ali; Newman, Mildred M.; McMillan, James D.

    1998-01-01

    The invention relates to microorganisms which normally do not ferment pentose sugar and which are genetically altered to ferment pentose sugar to produce ethanol, and fermentation processes utilizing the same. Examples include Zymomonas mobilis which has been transformed with combinations of E. coli genes for xylose isomerase, xylulokinase, transaldolase, transketolase, L-arabinose isomerase, L-ribulokinase, and L-ribulose 5-phosphate 4-epimerase. Expression of the added genes are under the control of Zymomonas mobilis promoters. These newly created microorganisms are useful for fermenting pentoses and glucose, produced by hydrolysis of hemicellulose and cellulose, to produce ethanol.

  9. Recombinant Zymomonas for pentose fermentation

    DOEpatents

    Picataggio, Stephen K.; Zhang, Min; Eddy, Christina K.; Deanda, Kristine A.

    1998-01-01

    The invention relates to microorganisms which normally do not ferment pentose sugar and which are genetically altered to ferment pentose sugar to produce ethanol, and fermentation processes utilizing the same. Examples include Zymomonas mobilis which has been transformed with combinations of E. coli genes for xylose isomerase, xylulokinase, transaldolase, transketolase, L-arabinose isomerase, L-ribulokinase, and L-ribulose-5-phosphate 4-epimerase. Expression of the added genes are under the control of Zymomonas mobilis promoters. These newly created microorganisms are useful for fermenting pentoses and glucose, produced by hydrolysis of hemicellulose and cellulose, to produce ethanol.

  10. Increased Flavonoid Compounds from Fermented Houttuynia cordata using Isolated Six of Bacillus from Traditionally Fermented Houttuynia cordata

    PubMed Central

    Kwon, Ryun Hee

    2012-01-01

    Flavonoids, which form a major component in Houttuynia cordata Thunb., display a wide range of pharmacological activities. The expression of plant flavonoids is partly regulated by fermentation. Therefore, we studied the effects of fermentation on H. cordata in order to identify the strains present during the fermentation process, and to determine whether fermented H. cordata could be used as a probiotic. Our results showed that all 6 of the bacterial strains isolated from fermented H. cordata (FHC) belonged to the genus Bacillus. As expected, fermenting H cordata also increased the flavonoid content as increases were observed in the levels of rutin, quercitrin, and quercetin. To test the effects of fermentation, we treated LPS-stimulated RAW264.7 cells with non-fermented H. cordata extracts (HCE) or FHC extracts (FHCE). Compared to the HCE-treated cells, the FHCE-treated cells showed increased viability. No cytotoxic effects were detected in the FHCE-treated groups in the 2 cell lines used in the study, namely, RAW264.7 and RBL-2H3. FHCE-treated HepG2 cells showed decreased growth, compared to HCE-treated HepG2 cells. These results indicate that the fermented H. cordata predominantly contained Bacillus strains. Furthermore, FHCE are able to prevent LPS-induced inflammatory effects and inhibit the growth of HepG2 cells. PMID:24278599

  11. Increased Flavonoid Compounds from Fermented Houttuynia cordata using Isolated Six of Bacillus from Traditionally Fermented Houttuynia cordata.

    PubMed

    Kwon, Ryun Hee; Ha, Bae Jin

    2012-06-01

    Flavonoids, which form a major component in Houttuynia cordata Thunb., display a wide range of pharmacological activities. The expression of plant flavonoids is partly regulated by fermentation. Therefore, we studied the effects of fermentation on H. cordata in order to identify the strains present during the fermentation process, and to determine whether fermented H. cordata could be used as a probiotic. Our results showed that all 6 of the bacterial strains isolated from fermented H. cordata (FHC) belonged to the genus Bacillus. As expected, fermenting H cordata also increased the flavonoid content as increases were observed in the levels of rutin, quercitrin, and quercetin. To test the effects of fermentation, we treated LPS-stimulated RAW264.7 cells with non-fermented H. cordata extracts (HCE) or FHC extracts (FHCE). Compared to the HCE-treated cells, the FHCE-treated cells showed increased viability. No cytotoxic effects were detected in the FHCE-treated groups in the 2 cell lines used in the study, namely, RAW264.7 and RBL-2H3. FHCE-treated HepG2 cells showed decreased growth, compared to HCE-treated HepG2 cells. These results indicate that the fermented H. cordata predominantly contained Bacillus strains. Furthermore, FHCE are able to prevent LPS-induced inflammatory effects and inhibit the growth of HepG2 cells.

  12. Dynamics of the yeast transcriptome during wine fermentation reveals a novel fermentation stress response

    PubMed Central

    Marks, Virginia D.; Ho Sui, Shannan J.; Erasmus, Daniel; van der Merwe, George K.; Brumm, Jochen; Wasserman, Wyeth W.; Bryan, Jennifer; van Vuuren, Hennie J. J.

    2016-01-01

    In this study, genome-wide expression analyses were used to study the response of Saccharomyces cerevisiae to stress throughout a 15-day wine fermentation. Forty per cent of the yeast genome significantly changed expression levels to mediate long-term adaptation to fermenting grape must. Among the genes that changed expression levels, a group of 223 genes was identified, which was designated as fermentation stress response (FSR) genes that were dramatically induced at various points during fermentation. FSR genes sustain high levels of induction up to the final time point and exhibited changes in expression levels ranging from four- to 80-fold. The FSR is novel; 62% of the genes involved have not been implicated in global stress responses and 28% of the FSR genes have no functional annotation. Genes involved in respiratory metabolism and gluconeogenesis were expressed during fermentation despite the presence of high concentrations of glucose. Ethanol, rather than nutrient depletion, seems to be responsible for entry of yeast cells into the stationary phase. PMID:18215224

  13. Yeasts Diversity in Fermented Foods and Beverages

    NASA Astrophysics Data System (ADS)

    Tamang, Jyoti Prakash; Fleet, Graham H.

    People across the world have learnt to culture and use the essential microorganisms for production of fermented foods and alcoholic beverages. A fermented food is produced either spontaneously or by adding mixed/pure starter culture(s). Yeasts are among the essential functional microorganisms encountered in many fermented foods, and are commercially used in production of baker's yeast, breads, wine, beer, cheese, etc. In Asia, moulds are predominant followed by amylolytic and alcohol-producing yeasts in the fermentation processes, whereas in Africa, Europe, Australia and America, fermented products are prepared exclusively using bacteria or bacteria-yeasts mixed cultures. This chapter would focus on the varieties of fermented foods and alcoholic beverages produced by yeasts, their microbiology and role in food fermentation, widely used commercial starters (pilot production, molecular aspects), production technology of some common commercial fermented foods and alcoholic beverages, toxicity and food safety using yeasts cultures and socio-economy

  14. Liquid sourdough fermentation: industrial application perspectives.

    PubMed

    Carnevali, P; Ciati, R; Leporati, A; Paese, M

    2007-04-01

    Sourdough fermentation is considered to play a key role to get improved flavour, texture, nutritional and shelf-life properties of bakery products. Since few years Barilla R&D has been focusing on liquid sourdough fermentation which may deserve several advantages with respect to traditional processes. The results showed that the micro-biota of sourdough markedly influences flavour and texture of bakery products. Particular attention has been paid to lactic acid bacteria and yeasts. Selected lactic acid bacteria and yeasts were tested in sourdough liquid fermentation as single strain or in association. The parameters of fermentations were optimized and standardized to set up a laboratory plant liquid fermentation. Only a few strains of lactic acid bacteria were found to be suitable for liquid fermentation alone or in association with yeasts. Fermentations were carried out at pilot plant and an industrial technology was developed. This work describes the results found for the organoleptic profile of an industrial bread started with liquid sourdough with respect to bakers' yeast bread without sourdough addition.

  15. High-strength fermentable wastewater reclamation through a sequential process of anaerobic fermentation followed by microalgae cultivation.

    PubMed

    Qi, Wenqiang; Chen, Taojing; Wang, Liang; Wu, Minghong; Zhao, Quanyu; Wei, Wei

    2017-03-01

    In this study, the sequential process of anaerobic fermentation followed by microalgae cultivation was evaluated from both nutrient and energy recovery standpoints. The effects of different fermentation type on the biogas generation, broth metabolites' composition, algal growth and nutrients' utilization, and energy conversion efficiencies for the whole processes were discussed. When the fermentation was designed to produce hydrogen-dominating biogas, the total energy conversion efficiency (TECE) of the sequential process was higher than that of the methane fermentation one. With the production of hydrogen in anaerobic fermentation, more organic carbon metabolites were left in the broth to support better algal growth with more efficient incorporation of ammonia nitrogen. By applying the sequential process, the heat value conversion efficiency (HVCE) for the wastewater could reach 41.2%, if methane was avoided in the fermentation biogas. The removal efficiencies of organic metabolites and NH 4 + -N in the better case were 100% and 98.3%, respectively. Copyright © 2016 Elsevier Ltd. All rights reserved.

  16. Efficacy of corn silage inoculants on the fermentation quality under farm conditions and their influence on Aspergillus parasitucus, A. flavus and A. fumigatus determined by q-PCR.

    PubMed

    Dogi, Cecilia A; Pellegrino, Matías; Poloni, Valeria; Poloni, Luis; Pereyra, Carina M; Sanabria, Analía; Pianzzola, María Julia; Dalcero, Ana; Cavaglieri, Lilia

    2015-01-01

    Laboratory-scale silos were prepared to evaluate the efficacy of two different lactic acid bacteria (LAB) on the fermentation quality and mycobiota of corn silage. Their influence on Aspergillus species' variability by using the q-PCR technique was studied. Silage inoculated with Lactobacillus rhamnosus RC007 or L. plantarum RC009 were compared with uninoculated silage. Silos were opened after 1, 7, 45, 90 and 120 days after ensiling. At the end of the ensiling period, silos were left open for 7 days to evaluate aerobic stability. Rapid lactic acid production and decline in pH values were seen in the early stages of fermentation in silage inoculated with L. rhamnosus RC007. After aerobic exposure, a significant decline in lactic acid content was observed in untreated and L. plantarum RC009-inoculated silages. Counts for yeasted and toxigenic fungus remained lower, after aerobic exposure, in L. rhamnosus RC007-inoculated silage, in comparison with L. plantarum RC009 and uninoculated silages. Comparing the influence exerted by both BAL, it was observed that L. rhamnosus RC007 was more efficient at inhibiting the three fungal species tested whose DNA concentrations, determined by q-PCR, oscillated near the initial value (pre-ensiling maize). The ability of L. rhamnosus RC007 to produce lactic acid rapidly and the decline in pH values in the early stages of the fermentation along with the reduction of yeast and mycotoxicogenic fungus after aerobic exposure shows its potential as a bio-control inoculant agent in animal feed.

  17. Camptothecine production by mixed fermentation of two endophytic fungi from Nothapodytes nimmoniana.

    PubMed

    Bhalkar, Bhumika N; Patil, Swapnil M; Govindwar, Sanjay P

    2016-01-01

    Two endophytic fungi isolated from the endangered plant Nothapodytes nimmoniana (Grah.) Mabb. were found to effectively synthesize CPT independent of their host plant under submerged fermentation conditions. Molecular characterization of fungi revealed their identity as Colletotrichum fructicola SUK1 (F1) and Corynespora cassiicola SUK2 (F2). Mixed fermentation experiments were carried out to study the effect of microbial signalling between the two fungal species on camptothecine production. Effect of culture parameters on CPT production was studied for both mono-cultures (F1 and F2) separately as well as for the mixed fermentation (F1 + F2). Further the most influencing ones were optimized statistically using response surface methodology. Statistical model based optimized parameters were whey (70 %), agitation rate (110 rpm), temperature (30 °C), and incubation period (7 d) for the mixed fermentation. Monocultures of the two fungal species F1 and F2 yielded CPT up to 33 ± 1.1 mg l(-1)and 69 ± 1.1 mg l(-1), respectively; while their mixed fermentation under the optimized conditions yielded up to 146 ± 0.2 mg l(-1). HPLC and LC-MS/MS techniques were used to analyze the products obtained. Copyright © 2016 British Mycological Society. Published by Elsevier Ltd. All rights reserved.

  18. Nitrifying aerobic granular sludge fermentation for releases of carbon source and phosphorus: The role of fermentation pH.

    PubMed

    Zou, Jinte; Pan, Jiyang; He, Hangtian; Wu, Shuyun; Xiao, Naidong; Ni, Yongjiong; Li, Jun

    2018-07-01

    The effect of fermentation pH (uncontrolled, 4 and 10) on the releases of carbon source and phosphorus from nitrifying aerobic granular sludge (N-AGS) was investigated. Meanwhile, metal ion concentration and microbial community characterization were explored during N-AGS fermentation. The results indicated that N-AGS fermentation at pH 10 significantly promoted the releases of soluble chemical oxygen demand (SCOD) and total volatile fatty acids (TVFAs). However, SCOD and TVFA released from N-AGS were inhibited at pH 4. Moreover, acidic condition promoted phosphorus release (mainly apatite) from N-AGS during anaerobic fermentation. Nevertheless, alkaline condition failed to increase phosphorus concentration due to the formation of chemical-phosphate precipitates. Compared with the previously reported flocculent sludge fermentation, N-AGS fermentation released more SCOD and TVFAs, possibly due to the greater extracellular polymeric substances content and some hydrolytic-acidogenic bacteria in N-AGS. Therefore, N-AGS alkaline fermentation facilitated the carbon source recovery, while N-AGS acidic fermentation benefited the phosphorus recovery. Copyright © 2018. Published by Elsevier Ltd.

  19. Incidence of double ovulation during the early postpartum period in lactating dairy cows.

    PubMed

    Kusaka, Hiromi; Miura, Hiroshi; Kikuchi, Motohiro; Sakaguchi, Minoru

    2017-03-15

    In lactating cattle, the incidence of twin calving has many negative impacts on production and reproduction in dairy farming. In almost all cases, natural twinning in dairy cattle is the result of double ovulation. It has been suggested that the milk production level of cows influences the number of ovulatory follicles. The objective of the present study was to investigate the incidence of double ovulations during the early postpartum period in relation to the productive and reproductive performance of dairy cows. The ovaries of 43 Holstein cows (26 primiparous and 17 multiparous) were ultrasonographically scanned throughout the three postpartum ovulation sequences. The incidence of double ovulation in the unilateral ovaries was 66.7%, with a higher incidence in the right ovary than in the left, whereas that in bilateral ovaries was 33.3%. When double ovulations were counted dividing into each side ovary in which ovulations occurred, the total frequency of ovulations deviated from a 1:1 ratio (60.3% in the right side and 39.7% in the left side, P < 0.05). In multiparous cows, double ovulation occurred more frequently than in primiparous cows (58.8% vs. 11.5% per cow and 30.0% vs. 3.8% per ovulation, respectively P < 0.01). The double ovulators experienced more anovulatory repeated waves of follicles before their first ovulations than the single ovulators, which resulted in an extension of the period from parturition to third ovulation (81.5 days vs. 64.2 days, P < 0.05). In the multiparous cows, the double ovulators exhibited higher peak milk yield (P < 0.01) with lower milk lactose concentration (P < 0.05), indicating the prevalence of a more severe negative energy balance during the postpartum 3-month compared to the multiparous single ovulators. Our results showed that, regardless of their parity, double ovulation had no impact on the reproductive performance of the cows. Two multiparous cows that experienced double ovulation during the early

  20. Effect of abomasal carbohydrates and live yeast on measures of postruminal fermentation.

    PubMed

    Gressley, T F; Davison, K A; Macies, J; Leonardi, C; McCarthy, M M; Nemec, L M; Rice, C A

    2016-01-01

    Two studies were conducted to evaluate the effects of abomasal carbohydrate infusion on nutrient digestibility and fecal measures. In Exp. 1, 5 Holstein steers were assigned to a Latin square with 1-wk periods and were abomasally infused on a single day at the end of each period with water alone, a single pulse dose of water with 1 g/kg BW oligofructose or cornstarch, or 4 pulse doses of water with 0.25 g/kg BW oligofructose or cornstarch administered every 6 h. Total tract nutrient digestibility was not affected by treatment except for a tendency for a decrease in starch digestibility in response to the 1 g/kg BW dose of cornstarch ( < 0.10). Compared with the control, both oligofructose and starch infusions caused similar decreases in fecal pH ( < 0.05) and increases in fecal short-chain fatty acids ( ≤ 0.01) measured 12 h after the first infusion, with the single 1 g/kg BW infusions causing a greater magnitude of pH change compared with the four 0.25-g/kg BW infusions ( < 0.01). All treatments increased concentration of fecal lipopolysaccharide compared with the control for at least 1 time point following the infusion ( < 0.05), with a greater increase observed for the 0.25 g/kg BW infusions of oligofructose compared with the other treatments ( < 0.05). Results of Exp. 1 indicate that both oligofructose and cornstarch infusions increased carbohydrate fermentation in the intestines and can be used as a method to evaluate the impact of excessive intestinal fermentation on intestinal health. In Exp. 2, 6 Holstein steers received abomasal pulse doses of 0 (control) or 10 g/d live var. (SB) according to a crossover design with 18-d periods. Abomasal infusions of 4 pulse doses of 0.25 g/kg BW oligofructose administered every 6 h were conducted on d 16 of each period. During the baseline period prior to the oligofructose challenge, there were no effects of SB on fecal measures except for an increase in apparent total tract NDF digestibility ( < 0.05), suggesting that

  1. Aerobic Stability and Effects of Yeasts during Deterioration of Non-fermented and Fermented Total Mixed Ration with Different Moisture Levels.

    PubMed

    Hao, W; Wang, H L; Ning, T T; Yang, F Y; Xu, C C

    2015-06-01

    The present experiment evaluated the influence of moisture level and anaerobic fermentation on aerobic stability of total mixed ration (TMR). The dynamic changes in chemical composition and microbial population that occur after air exposure were examined, and the species of yeast associated with the deterioration process were also identified in both non-fermented and fermented TMR to deepen the understanding of aerobic deterioration. The moisture levels of TMR in this experiment were adjusted to 400 g/kg (low moisture level, LML), 450 g/kg (medium moisture level, MML), and 500 g/kg (high moisture level, HML), and both non-fermented and 56-d-fermented TMR were subjected to air exposure to determine aerobic stability. Aerobic deterioration resulted in high losses of nutritional components and largely reduced dry matter digestibility. Non-fermented TMR deteriorated during 48 h of air exposure and the HML treatment was more aerobically unstable. On dry matter (DM) basis, yeast populations significantly increased from 10(7) to 10(10) cfu/g during air exposure, and Candida ethanolica was the predominant species during deterioration in non-fermented TMR. Fermented TMR exhibited considerable resistance to aerobic deterioration. Spoilage was only observed in the HML treatment and its yeast population increased dramatically to 10(9) cfu/g DM when air exposure progressed to 30 d. Zygosaccharomyces bailii was the sole yeast species isolated when spoilage occurred. These results confirmed that non-fermented and fermented TMR with a HML are more prone to spoilage, and fermented TMR has considerable resistance to aerobic deterioration. Yeasts can trigger aerobic deterioration in both non-fermented and fermented TMR. C. ethanolica may be involved in the spoilage of non-fermented TMR and the vigorous growth of Z. bailii can initiate aerobic deterioration in fermented TMR.

  2. Aerobic Stability and Effects of Yeasts during Deterioration of Non-fermented and Fermented Total Mixed Ration with Different Moisture Levels

    PubMed Central

    Hao, W.; Wang, H. L.; Ning, T. T.; Yang, F. Y.; Xu, C. C.

    2015-01-01

    The present experiment evaluated the influence of moisture level and anaerobic fermentation on aerobic stability of total mixed ration (TMR). The dynamic changes in chemical composition and microbial population that occur after air exposure were examined, and the species of yeast associated with the deterioration process were also identified in both non-fermented and fermented TMR to deepen the understanding of aerobic deterioration. The moisture levels of TMR in this experiment were adjusted to 400 g/kg (low moisture level, LML), 450 g/kg (medium moisture level, MML), and 500 g/kg (high moisture level, HML), and both non-fermented and 56-d-fermented TMR were subjected to air exposure to determine aerobic stability. Aerobic deterioration resulted in high losses of nutritional components and largely reduced dry matter digestibility. Non-fermented TMR deteriorated during 48 h of air exposure and the HML treatment was more aerobically unstable. On dry matter (DM) basis, yeast populations significantly increased from 107 to 1010 cfu/g during air exposure, and Candida ethanolica was the predominant species during deterioration in non-fermented TMR. Fermented TMR exhibited considerable resistance to aerobic deterioration. Spoilage was only observed in the HML treatment and its yeast population increased dramatically to 109 cfu/g DM when air exposure progressed to 30 d. Zygosaccharomyces bailii was the sole yeast species isolated when spoilage occurred. These results confirmed that non-fermented and fermented TMR with a HML are more prone to spoilage, and fermented TMR has considerable resistance to aerobic deterioration. Yeasts can trigger aerobic deterioration in both non-fermented and fermented TMR. C. ethanolica may be involved in the spoilage of non-fermented TMR and the vigorous growth of Z. bailii can initiate aerobic deterioration in fermented TMR. PMID:25925059

  3. Kinetic model of continuous ethanol fermentation in closed-circulating process with pervaporation membrane bioreactor by Saccharomyces cerevisiae.

    PubMed

    Fan, Senqing; Chen, Shiping; Tang, Xiaoyu; Xiao, Zeyi; Deng, Qing; Yao, Peina; Sun, Zhaopeng; Zhang, Yan; Chen, Chunyan

    2015-02-01

    Unstructured kinetic models were proposed to describe the principal kinetics involved in ethanol fermentation in a continuous and closed-circulating fermentation (CCCF) process with a pervaporation membrane bioreactor. After ethanol was removed in situ from the broth by the membrane pervaporation, the secondary metabolites accumulated in the broth became the inhibitors to cell growth. The cell death rate related to the deterioration of the culture environment was described as a function of the cell concentration and fermentation time. In CCCF process, 609.8 g L(-1) and 750.1 g L(-1) of ethanol production were obtained in the first run and second run, respectively. The modified Gompertz model, correlating the ethanol production with the fermentation period, could be used to describe the ethanol production during CCCF process. The fitting results by the models showed good agreement with the experimental data. These models could be employed for the CCCF process technology development for ethanol fermentation. Copyright © 2014 Elsevier Ltd. All rights reserved.

  4. Rapid discrimination of strain-dependent fermentation characteristics among Lactobacillus strains by NMR-based metabolomics of fermented vegetable juice

    PubMed Central

    Nakamura, Toshihide; Sekiyama, Yasuyo; Kikuchi, Jun

    2017-01-01

    In this study, we investigated the applicability of NMR-based metabolomics to discriminate strain-dependent fermentation characteristics of lactic acid bacteria (LAB), which are important microorganisms for fermented food production. To evaluate the discrimination capability, six type strains of Lactobacillus species and six additional L. brevis strains were used focusing on i) the difference between homo- and hetero-lactic fermentative species and ii) strain-dependent characteristics within L. brevis. Based on the differences in the metabolite profiles of fermented vegetable juices, non-targeted principal component analysis (PCA) clearly separated the samples into those inoculated with homo- and hetero-lactic fermentative species. The separation was primarily explained by the different levels of dominant metabolites (lactic acid, acetic acid, ethanol, and mannitol). Orthogonal partial least squares discrimination analysis, based on a regions-of-interest (ROIs) approach, revealed the contribution of low-abundance metabolites: acetoin, phenyllactic acid, p-hydroxyphenyllactic acid, glycerophosphocholine, and succinic acid for homolactic fermentation; and ornithine, tyramine, and γ-aminobutyric acid (GABA) for heterolactic fermentation. Furthermore, ROIs-based PCA of seven L. brevis strains separated their strain-dependent fermentation characteristics primarily based on their ability to utilize sucrose and citric acid, and convert glutamic acid and tyrosine into GABA and tyramine, respectively. In conclusion, NMR metabolomics successfully discriminated the fermentation characteristics of the tested strains and provided further information on metabolites responsible for these characteristics, which may impact the taste, aroma, and functional properties of fermented foods. PMID:28759594

  5. Characteristics of spoilage-associated secondary cucumber fermentation

    USDA-ARS?s Scientific Manuscript database

    Secondary fermentations during the bulk storage of fermented cucumbers can result in spoilage that causes a total loss of the fermented product, at an estimated cost of $6,000 to $15,000 per affected tank. Previous research has suggested that such fermentations are the result of microbiological util...

  6. Acetone-butanol fermentation of marine macroalgae.

    PubMed

    Huesemann, Michael H; Kuo, Li-Jung; Urquhart, Lindsay; Gill, Gary A; Roesijadi, Guri

    2012-03-01

    The objective of this study was to subject mannitol, either as a sole carbon source or in combination with glucose, and aqueous extracts of the kelp Saccharina spp., containing mannitol and laminarin, to acetone-butanol fermentation by Clostridium acetobutylicum (ATCC 824). Both mannitol and glucose were readily fermented. Mixed substrate fermentations with glucose and mannitol resulted in diauxic growth of C. acetobutylicum with glucose depletion preceding mannitol utilization. Fermentation of kelp extract exhibited triauxic growth, with an order of utilization of free glucose, mannitol, and bound glucose, presumably laminarin. The lag in laminarin utilization reflected the need for enzymatic hydrolysis of this polysaccharide into fermentable sugars. The butanol and total solvent yields were 0.12 g/g and 0.16 g/g, respectively, indicating that significant improvements are still needed to make industrial-scale acetone-butanol fermentations of seaweed economically feasible. Copyright © 2012 Elsevier Ltd. All rights reserved.

  7. Yeast ecology of Kombucha fermentation.

    PubMed

    Teoh, Ai Leng; Heard, Gillian; Cox, Julian

    2004-09-01

    Kombucha is a traditional fermentation of sweetened tea, involving a symbiosis of yeast species and acetic acid bacteria. Despite reports of different yeast species being associated with the fermentation, little is known of the quantitative ecology of yeasts in Kombucha. Using oxytetracycline-supplemented malt extract agar, yeasts were isolated from four commercially available Kombucha products and identified using conventional biochemical and physiological tests. During the fermentation of each of the four products, yeasts were enumerated from both the cellulosic pellicle and liquor of the Kombucha. The number and diversity of species varied between products, but included Brettanomyces bruxellensis, Candida stellata, Schizosaccharomyces pombe, Torulaspora delbrueckii and Zygosaccharomyces bailii. While these yeast species are known to occur in Kombucha, the enumeration of each species present throughout fermentation of each of the four Kombucha cultures demonstrated for the first time the dynamic nature of the yeast ecology. Kombucha fermentation is, in general, initiated by osmotolerant species, succeeded and ultimately dominated by acid-tolerant species.

  8. Predictive modelling of Lactobacillus casei KN291 survival in fermented soy beverage.

    PubMed

    Zielińska, Dorota; Dorota, Zielińska; Kołożyn-Krajewska, Danuta; Danuta, Kołożyn-Krajewska; Goryl, Antoni; Antoni, Goryl; Motyl, Ilona

    2014-02-01

    The aim of the study was to construct and verify predictive growth and survival models of a potentially probiotic bacteria in fermented soy beverage. The research material included natural soy beverage (Polgrunt, Poland) and the strain of lactic acid bacteria (LAB) - Lactobacillus casei KN291. To construct predictive models for the growth and survival of L. casei KN291 bacteria in the fermented soy beverage we design an experiment which allowed the collection of CFU data. Fermented soy beverage samples were stored at various temperature conditions (5, 10, 15, and 20°C) for 28 days. On the basis of obtained data concerning the survival of L. casei KN291 bacteria in soy beverage at different temperature and time conditions, two non-linear models (r(2)= 0.68-0.93) and two surface models (r(2)=0.76-0.79) were constructed; these models described the behaviour of the bacteria in the product to a satisfactory extent. Verification of the surface models was carried out utilizing the validation data - at 7°C during 28 days. It was found that applied models were well fitted and charged with small systematic errors, which is evidenced by accuracy factor - Af, bias factor - Bf and mean squared error - MSE. The constructed microbiological growth and survival models of L. casei KN291 in fermented soy beverage enable the estimation of products shelf life period, which in this case is defined by the requirement for the level of the bacteria to be above 10(6) CFU/cm(3). The constructed models may be useful as a tool for the manufacture of probiotic foods to estimate of their shelf life period.

  9. Yeasts are essential for cocoa bean fermentation.

    PubMed

    Ho, Van Thi Thuy; Zhao, Jian; Fleet, Graham

    2014-03-17

    Cocoa beans (Theobroma cacao) are the major raw material for chocolate production and fermentation of the beans is essential for the development of chocolate flavor precursors. In this study, a novel approach was used to determine the role of yeasts in cocoa fermentation and their contribution to chocolate quality. Cocoa bean fermentations were conducted with the addition of 200ppm Natamycin to inhibit the growth of yeasts, and the resultant microbial ecology and metabolism, bean chemistry and chocolate quality were compared with those of normal (control) fermentations. The yeasts Hanseniaspora guilliermondii, Pichia kudriavzevii and Kluyveromyces marxianus, the lactic acid bacteria Lactobacillus plantarum and Lactobacillus fermentum and the acetic acid bacteria Acetobacter pasteurianus and Gluconobacter frateurii were the major species found in the control fermentation. In fermentations with the presence of Natamycin, the same bacterial species grew but yeast growth was inhibited. Physical and chemical analyses showed that beans fermented without yeasts had increased shell content, lower production of ethanol, higher alcohols and esters throughout fermentation and lesser presence of pyrazines in the roasted product. Quality tests revealed that beans fermented without yeasts were purplish-violet in color and not fully brown, and chocolate prepared from these beans tasted more acid and lacked characteristic chocolate flavor. Beans fermented with yeast growth were fully brown in color and gave chocolate with typical characters which were clearly preferred by sensory panels. Our findings demonstrate that yeast growth and activity were essential for cocoa bean fermentation and the development of chocolate characteristics. Crown Copyright © 2014. Published by Elsevier B.V. All rights reserved.

  10. [Effect of products of thermophilous methane fermentation on the fermentation of fruit must by Saccharomyces vini].

    PubMed

    Mikhlin, E D; Kotomina, E N; Pisarnitsky

    1975-01-01

    Experiments were carried out to study the effect of extracts from products of thermophilous methane fermentation at a dose of 0.7+2.0 ml/100 ml on the proliferation and fermentation activity of yeast Saccharomyces vini of the Yablochnaya-7 and Vishnevaya-33 race during their cultivation in the Hansen medium and in the apple and cranberry must with a normal and elevated content of sugar and acid. In some experiments the must was enriched in (NH4)2HPO4 at a dose of 0.3 g/l. Additions of small amounts of products of thermophilous methane fermentation accelerated fermentation of fruit musts with a normal sugar content and to a greater extent musts with an increased sugar content (27%). In the must enriched in (NH4)2HPO4 an almost complete (over 98%) fermentation of sugar developed for 27 days. In the must with an increased acidity (due to citric acid added to bring titrable acidity to 25 g/l) additions of the preparation also accerlerated the begining of the fermentation and increased its intensity.

  11. Impact of preacidification of milk and fermentation time on the properties of yogurt.

    PubMed

    Peng, Y; Horne, D S; Lucey, J A

    2009-07-01

    . Preacidification of milk increased the solubilization of CCP, increased the early loss of CCP crosslinks, and produced weak gels. Long fermentation times allowed more time for solubilization of CCP during the critical gelation stage of the process and increased the possibility of greater casein rearrangements; both could have contributed to the increase in whey separation.

  12. Replacement of sugars to hydrogen production by Rhodobacter capsulatus using dark fermentation effluent as substrate.

    PubMed

    Silva, Felipe Thales Moreira; Moreira, Luiza Rojas; de Souza Ferreira, Juliana; Batista, Fabiana Regina Xavier; Cardoso, Vicelma Luiz

    2016-01-01

    Hydrogen is a promising alternative for the increased global energy demand since it has high energy density and is a clean fuel. The aim of this work was to evaluate the photo-fermentation by Rhodobacter capsulatus, using the dark fermentation effluent as substrate. Different systems were tested by changing the type of sugar in the dark fermentation, investigating the influence of supplementing DFE with sugar and adding alternate and periodically lactose and glucose throughout the process. The supplementation of the DFE with sugar resulted in higher H2 productivity and the replacement of the sugars repeatedly during the photo-fermentation process was important to maintain the cell culture active. By controlling the residual amount of sugar, bacteria inhibition was avoided; lactic acid, that was toxic to the biomass, was consumed and the metabolic route of butyric acid production was predominant. Under optimum conditions, the H2 productivity reached 208.40mmolH2/Ld in 52h. Copyright © 2015 Elsevier Ltd. All rights reserved.

  13. Acetone-butanol Fermentation of Marine Macroalgae

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Huesemann, Michael H.; Kuo, Li-Jung; Urquhart, Lindsay A.

    2012-03-01

    Mannitol and laminarin, which are present at high concentrations in the brown macroalga Saccharina spp., a type of kelp, are potential biochemical feedstocks for butanol production. To test their bioconversion potential, aqueous extracts of the kelp Saccharina spp., mannitol, and glucose (a product of laminarin hydrolysis) were subjected to acetone-butanol fermentation by Clostridium acetobutylicum (ATCC 824). Both mannitol and glucose were readily fermented. Mixed substrate fermentations with glucose and mannitol resulted in diauxic growth of C. acetobutylicum with glucose depletion preceding mannitol utilization. Fermentation of kelp extract exhibited triauxic growth, with an order of utilization of free glucose, mannitol, andmore » bound glucose, presumably laminarin. The lag in laminarin utilization reflected the need for enzymatic hydrolysis of this polysaccharide into fermentable sugars. The butanol and total solvent yields were 0.12 g/g and 0.16 g/g, respectively, indicating that significant improvements are still needed to make industrial-scale acetone-butanol fermentations of seaweed economically feasible.« less

  14. Ultrafiltration of hemicellulose hydrolysate fermentation broth

    NASA Astrophysics Data System (ADS)

    Kresnowati, M. T. A. P.; Desiriani, Ria; Wenten, I. G.

    2017-03-01

    Hemicelulosic material is often used as the main substrate to obtain high-value products such as xylose. The five carbon sugar, xylose, could be further processed by fermentation to produce xylitol. However, not only the hemicellulose hydrolysate fermentation broth contains xylitol, but also metabolite products, residual substances, biomass and mineral salts. Therefore, in order to obtain the end products, various separation processes are required to separate and purify the desired product from the fermentation broth. One of the most promising downstream processing methods of fermentation broth clarification is ultrafiltration due to its potential for energy saving and higher purity. In addition, ultrafiltration membrane has a high performance in separating inhibitory components in the fermentation broth. This paper assesses the influence of operating conditions; including trans-membrane pressure, velocity, pH of the fermentation broth solutions, and also to the xylitol concentration in the product. The challenges of the ultrafiltration process will be pointed out.

  15. Associations among Wine Grape Microbiome, Metabolome, and Fermentation Behavior Suggest Microbial Contribution to Regional Wine Characteristics

    PubMed Central

    Bokulich, Nicholas A.; Collins, Thomas S.; Masarweh, Chad; Allen, Greg; Heymann, Hildegarde; Ebeler, Susan E.

    2016-01-01

    ABSTRACT Regionally distinct wine characteristics (terroir) are an important aspect of wine production and consumer appreciation. Microbial activity is an integral part of wine production, and grape and wine microbiota present regionally defined patterns associated with vineyard and climatic conditions, but the degree to which these microbial patterns associate with the chemical composition of wine is unclear. Through a longitudinal survey of over 200 commercial wine fermentations, we demonstrate that both grape microbiota and wine metabolite profiles distinguish viticultural area designations and individual vineyards within Napa and Sonoma Counties, California. Associations among wine microbiota and fermentation characteristics suggest new links between microbiota, fermentation performance, and wine properties. The bacterial and fungal consortia of wine fermentations, composed from vineyard and winery sources, correlate with the chemical composition of the finished wines and predict metabolite abundances in finished wines using machine learning models. The use of postharvest microbiota as an early predictor of wine chemical composition is unprecedented and potentially poses a new paradigm for quality control of agricultural products. These findings add further evidence that microbial activity is associated with wine terroir. PMID:27302757

  16. Early Adolescence: Celestial Meetings - Synodic Periods.

    ERIC Educational Resources Information Center

    Science and Children, 1985

    1985-01-01

    Rather than memorize numbers for sidereal periods of planets (time to orbit the sun), students can learn to determine these times through simple calculations. Comparison of a planet's synodic period to earth's year of 365 days is made, then multiplication to derive a full circle of 360 degrees establishes the sidereal period. (DH)

  17. Membrane-integrated fermentation system for improving the optical purity of D-lactic acid produced during continuous fermentation.

    PubMed

    Sawai, Hideki; Na, Kyungsu; Sasaki, Nanami; Mimitsuka, Takashi; Minegishi, Shin-ichi; Henmi, Masahiro; Yamada, Katsushige; Shimizu, Sakayu; Yonehara, Tetsu

    2011-01-01

    This report describes the production of highly optically pure D-lactic acid by the continuous fermentation of Sporolactobacillus laevolacticus and S. inulinus, using a membrane-integrated fermentation (MFR) system. The optical purity of D-lactic acid produced by the continuous fermentation system was greater than that produced by batch fermentation; the maximum value for the optical purity of D-lactic acid reached 99.8% enantiomeric excess by continuous fermentation when S. leavolacticus was used. The volumetric productivity of the optically pure D-lactic acid was about 12 g/L/h, this being approximately 11-fold higher than that obtained by batch fermentation. An enzymatic analysis indicated that both S. laevolacticus and S. inulinus could convert L-lactic acid to D-lactic acid by isomerization after the late-log phase. These results provide evidence for an effective bio-process to produce D-lactic acid of greater optical purity than has conventionally been achieved to date.

  18. Early-onset neonatal sepsis is associated with a high heart rate during automatically selected stationary periods.

    PubMed

    Nguyen, Nga; Vandenbroucke, Laurent; Hernández, Alfredo; Pham, Tu; Beuchée, Alain; Pladys, Patrick

    2017-05-01

    This study examined the heart rate variability characteristics associated with early-onset neonatal sepsis in a prospective, observational controlled study. Eligible patients were full-term neonates hospitalised with clinical signs that suggested early-onset sepsis and a C-reactive protein of >10 mg/L. Sepsis was considered proven in cases of symptomatic septicaemia, meningitis, pneumonia or enterocolitis. Heart rate variability parameters (n = 16) were assessed from five-, 15- and 30-minute stationary sequences automatically selected from electrocardiographic recordings performed at admission and compared with a control group using the U-test with post hoc Benjamini-Yekutieli correction. Stationary sequences corresponded to the periods with the lowest changes of heart rate variability over time. A total of 40 full-term infants were enrolled, including 14 with proven sepsis. The mean duration of the cardiac cycle length was lower in the proven sepsis group than in the control group (n = 11), without other significant changes in heart rate variability parameters. These durations, measured in five-minute stationary periods, were 406 (367-433) ms in proven sepsis group versus 507 (463-522) ms in the control group (p < 0.05). Early-onset neonatal sepsis was associated with a high mean heart rate measured during automatically selected stationary periods. ©2017 Foundation Acta Paediatrica. Published by John Wiley & Sons Ltd.

  19. Relations between transit time, fermentation products, and hydrogen consuming flora in healthy humans.

    PubMed

    El Oufir, L; Flourié, B; Bruley des Varannes, S; Barry, J L; Cloarec, D; Bornet, F; Galmiche, J P

    1996-06-01

    To investigate whether transit time could influence H2 consuming flora and certain indices of colonic bacterial fermentation. Eight healthy volunteers (four methane excretors and four non-methane excretors) were studied for three, three week periods during which they received a controlled diet alone (control period), and then the same diet with cisapride or loperamide. At the end of each period, mean transit time (MTT) was estimated, an H2 lactulose breath test was performed, and stools were analysed. In the control period, transit time was inversely related to faecal weight, sulphate reducing bacteria counts, concentrations of total short chain fatty acids (SCFAs), propionic and butyric acids, and H2 excreted in breath after lactulose ingestion. Conversely, transit time was positively related to faecal pH and tended to be related to methanogen counts. Methanogenic bacteria counts were inversely related to those of sulphate reducing bacteria and methane excretors had slower MTT and lower sulphate reducing bacteria counts than non-methane excretors. Compared with the control period, MTT was significantly shortened (p < 0.05) by cisapride and prolonged (p < 0.05) by loperamide (73 (11) hours, 47 (5) hours and 147 (12) hours for control, cisapride, and loperamide, respectively, mean (SD)). Cisapride reduced transit time was associated with (a) a significant rise in faecal weight, sulphate reducing bacteria, concentrations of total SCFAs, and propionic and butyric acids and breath H2 as well as (b) a significant fall in faecal pH and breath CH4 excretion, and (c) a non-significant decrease in the counts of methanogenic bacteria. Reverse relations were roughly the same during the loperamide period including a significant rise in the counts of methanogenic bacteria and a significant fall in those of sulphate reducing bacteria. Transit time differences between healthy volunteers are associated with differences in H2 consuming flora and certain indices of colonic

  20. Relations between transit time, fermentation products, and hydrogen consuming flora in healthy humans.

    PubMed Central

    El Oufir, L; Flourié, B; Bruley des Varannes, S; Barry, J L; Cloarec, D; Bornet, F; Galmiche, J P

    1996-01-01

    BACKGROUND/AIMS: To investigate whether transit time could influence H2 consuming flora and certain indices of colonic bacterial fermentation. METHODS: Eight healthy volunteers (four methane excretors and four non-methane excretors) were studied for three, three week periods during which they received a controlled diet alone (control period), and then the same diet with cisapride or loperamide. At the end of each period, mean transit time (MTT) was estimated, an H2 lactulose breath test was performed, and stools were analysed. RESULTS: In the control period, transit time was inversely related to faecal weight, sulphate reducing bacteria counts, concentrations of total short chain fatty acids (SCFAs), propionic and butyric acids, and H2 excreted in breath after lactulose ingestion. Conversely, transit time was positively related to faecal pH and tended to be related to methanogen counts. Methanogenic bacteria counts were inversely related to those of sulphate reducing bacteria and methane excretors had slower MTT and lower sulphate reducing bacteria counts than non-methane excretors. Compared with the control period, MTT was significantly shortened (p < 0.05) by cisapride and prolonged (p < 0.05) by loperamide (73 (11) hours, 47 (5) hours and 147 (12) hours for control, cisapride, and loperamide, respectively, mean (SD)). Cisapride reduced transit time was associated with (a) a significant rise in faecal weight, sulphate reducing bacteria, concentrations of total SCFAs, and propionic and butyric acids and breath H2 as well as (b) a significant fall in faecal pH and breath CH4 excretion, and (c) a non-significant decrease in the counts of methanogenic bacteria. Reverse relations were roughly the same during the loperamide period including a significant rise in the counts of methanogenic bacteria and a significant fall in those of sulphate reducing bacteria. CONCLUSIONS: Transit time differences between healthy volunteers are associated with differences in H2

  1. Characterization of lactic acid bacteria isolated from a Thai low-salt fermented fish product and the role of garlic as substrate for fermentation.

    PubMed

    Paludan-Müller, C; Huss, H H; Gram, L

    1999-02-18

    Lactic acid bacteria (LAB) isolated from raw materials (fish, rice, garlic and banana leaves) and processed som-fak (a Thai low-salt fermented fish product) were characterized by API 50-CH and other phenotypic criteria. Lactococcus lactis subsp. lactis and Leuconostoc citreum were specifically associated with fish fillet and minced fish, Lactobacillus paracasei subsp. paracasei with boiled rice and Weisella confusa with garlic mix and banana leaves. In addition, Lactobacillus plantarum, Lactobacillus pentosus and Pediococcus pentosaceus were isolated from raw materials. A succession of aciduric, homofermentative lactobacillus species, dominated by Lb. plantarum/pentosus, was found during fermentation. In total, 9% of the strains fermented starch and 19% fermented garlic, the two main carbohydrate components in som-fak. The ability to ferment garlic was paralleled by a capacity to ferment inulin. An increased percentage of garlic fermenting strains was found during fermentation of som-fak, from 8% at day 1 to 40% at day 5. No starch fermenting strains were isolated during fermentation. Three mixed LAB cultures, composed of either starch fermenting Lc. lactis subsp. lactis and Lb. paracasei subsp. paracasei, or garlic fermenting Lb. plantarum and Pd. pentosaceus, or a combination of these strains were inoculated into laboratory prepared som-fak with or without garlic. In som-fak without garlic, pH was above 4.8 after three days, irrespective of addition of mixed LAB cultures. The starch fermenting LAB were unable to ferment som-fak and sensory spoilage occurred after three days. Fermentation with the combined mix of starch and garlic fermenting strains led to production of 2.5% acid and a decrease in pH to 4.5 in two days. The fermentation was slightly slower with the garlic fermenting strains alone. This is the first report describing the role of garlic as carbohydrate source for LAB in fermented fish products.

  2. Bacterial DNA Detected in Japanese Rice Wines and the Fermentation Starters.

    PubMed

    Terasaki, Momoka; Fukuyama, Akari; Takahashi, Yurika; Yamada, Masato; Nishida, Hiromi

    2017-12-01

    As Japanese rice wine (sake) brewing is not done aseptically, bacterial contamination is conceivable during the process of sake production. There are two types of the fermentation starter, sokujo-moto and yamahai-moto (kimoto). We identified bacterial DNA found in various sakes, the sokujo-moto and the yamahai-moto making just after sake yeast addition. Each sake has a unique variety of bacterial DNA not observed in other sakes. Although most bacterial DNA sequences detected in the sokujo-moto were found in sakes of different sake breweries, most bacterial DNA sequences detected in the yamahai-moto at the early stage of the starter fermentation were not detected in any sakes. Our findings demonstrate that various bacteria grow and then die during the process of sake brewing, as indicated by the presence of trace levels of bacterial DNA.

  3. Effects of different fermentation parameters on quality characteristics of kefir.

    PubMed

    Kök-Taş, Tuğba; Seydim, Atif C; Ozer, Barbaros; Guzel-Seydim, Zeynep B

    2013-02-01

    The main objective of the study was to determine the effects of different fermentation parameters on kefir quality. Kefir samples were produced using kefir grains or natural kefir starter culture, and fermentation was carried out under normal or modified atmosphere (10% CO(2)) conditions. The microbiological (lactobacilli, lactococci, Lactobacillus acidophilus, Bifidobacterium spp., and yeasts), chemical (pH, lactic acid, total solids, protein, ethanol, exopolysaccharide contents), rheological, and sensory properties of kefir samples were investigated during a 21-d storage period. The use of different fermentation parameters or the choice of grain versus natural kefir starter culture did not significantly affect the content of microorganisms. Lactobacilli, lactococci, and yeast contents of kefir samples varied between 9.21 and 9.28, 9.23 and 9.29, and 4.71 and 5.53 log cfu/mL, respectively, on d 1 of storage. Contents of L. acidophilus and Bifidobacterium spp. were between 5.78 and 6.43 and between 3.19 and 6.14 log cfu/mL, respectively, during 21 d of storage. During the storage period, pH, lactic acid (%), total solids (%), protein (%), acetaldehyde, and ethanol contents of kefir samples ranged from 4.29 to 4.53, from 0.81 to 0.95%, from 7.81 to 8.21%, from 3.09 to 3.48%, from 3.8 to 23.6 mg/L, and from 76.5 to 5,147 mg/L, respectively. The exopolysaccharide contents of the samples decreased during 21 d of cold storage; the samples fermented under modified atmosphere had relatively higher exopolysaccharide contents, indicating higher potential therapeutic properties. The kefir samples exhibited non-Newtonian pseudoplastic flow behavior according to the power law model. According to the sensory results, kefir produced from natural kefir starter culture under CO(2) atmosphere had the highest overall evaluation score at d 1. Copyright © 2013 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  4. A review on traditional Turkish fermented non-alcoholic beverages: microbiota, fermentation process and quality characteristics.

    PubMed

    Altay, Filiz; Karbancıoglu-Güler, Funda; Daskaya-Dikmen, Ceren; Heperkan, Dilek

    2013-10-01

    Shalgam juice, hardaliye, boza, ayran (yoghurt drink) and kefir are the most known traditional Turkish fermented non-alcoholic beverages. The first three are obtained from vegetables, fruits and cereals, and the last two ones are made of milk. Shalgam juice, hardaliye and ayran are produced by lactic acid fermentation. Their microbiota is mainly composed of lactic acid bacteria (LAB). Lactobacillus plantarum, Lactobacillus brevis and Lactobacillus paracasei subsp. paracasei in shalgam fermentation and L. paracasei subsp. paracasei and Lactobacillus casei subsp. pseudoplantarum in hardaliye fermentation are predominant. Ayran is traditionally prepared by mixing yoghurt with water and salt. Yoghurt starter cultures are used in industrial ayran production. On the other hand, both alcohol and lactic acid fermentation occur in boza and kefir. Boza is prepared by using a mixture of maize, wheat and rice or their flours and water. Generally previously produced boza or sourdough/yoghurt are used as starter culture which is rich in Lactobacillus spp. and yeasts. Kefir is prepared by inoculation of raw milk with kefir grains which consists of different species of yeasts, LAB, acetic acid bacteria in a protein and polysaccharide matrix. The microbiota of boza and kefir is affected from raw materials, the origin and the production methods. In this review, physicochemical properties, manufacturing technologies, microbiota and shelf life and spoilage of traditional fermented beverages were summarized along with how fermentation conditions could affect rheological properties of end product which are important during processing and storage. Copyright © 2013. Published by Elsevier B.V.

  5. Recombinant zymomonas for pentose fermentation

    DOEpatents

    Picataggio, Stephen K.; Zhang, Min; Eddy, Christina K.; Deanda, Kristine A.; Finkelstein, Mark

    1996-01-01

    The invention relates to microorganisms which normally do not ferment a pentose sugar and which are genetically altered to ferment this pentose to produce ethanol. A representative example is Zymomonas mobilis which has been transformed with E. coli xylose isomerase, xylulokinase, transaldolase and transketolase genes. Expression of the added genes are under the control of Zymomonas mobilis promoters. This newly created microorganism is useful for fermenting pentoses and glucose, produced by hydrolysis of hemicellulose and cellulose, to produce ethanol.

  6. Inhibitory effect of essential oils against Lactobacillus rhamnosus and starter culture in fermented milk during its shelf-life period

    PubMed Central

    Moritz, Cristiane Mengue Feniman; Rall, Vera Lúcia Mores; Saeki, Margarida Júri; Júnior, Ary Fernandes

    2012-01-01

    The use of essential oils in foods has attracted great interest, due to their antagonistic action against pathogenic microorganisms. However, this action is undesirable for probiotic foods, as products containing Lactobacillus rhamnosus. The aim of the present study was to measure the sensitivity profile of L. rhamnosus and a yogurt starter culture in fermented milk, upon addition of increasing concentrations of cinnamon, clove and mint essential oils. Essential oils were prepared by steam distillation, and chemically characterised by gas chromatography-mass spectrometry (GC-MS) and determination of density. Survival curves were obtained from counts of L. rhamnosus and the starter culture (alone and in combination), upon addition of 0.04% essential oils. In parallel, titratable acidity was monitored over 28 experimental days. Minimum inhibitory concentration values, obtained using the microdilution method in Brain Heart Infusion medium, were 0.025, 0.2 and 0.4% for cinnamon, clove and mint essential oils, respectively. Cinnamon essential oil had the highest antimicrobial activity, especially against the starter culture, interfering with lactic acid production. Although viable cell counts of L. rhamnosus were lower following treatment with all 3 essential oils, relative to controls, these results were not statistically significant; in addition, cell counts remained greater than the minimum count of 108CFU/mL required for a product to be considered a probiotic. Thus, although use of cinnamon essential oil in yogurt makes starter culture fermentation unfeasible, it does not prevent the application of L. rhamnosus to probiotic fermented milk. Furthermore, clove and mint essential oil caused sublethal stress to L. rhamnosus. PMID:24031939

  7. Wheat bran extract alters colonic fermentation and microbial composition, but does not affect faecal water toxicity: a randomised controlled trial in healthy subjects.

    PubMed

    Windey, Karen; De Preter, Vicky; Huys, Geert; Broekaert, Willem F; Delcour, Jan A; Louat, Thierry; Herman, Jean; Verbeke, Kristin

    2015-01-28

    Wheat bran extract (WBE), containing arabinoxylan-oligosaccharides that are potential prebiotic substrates, has been shown to modify bacterial colonic fermentation in human subjects and to beneficially affect the development of colorectal cancer (CRC) in rats. However, it is unclear whether these changes in fermentation are able to reduce the risk of developing CRC in humans. The aim of the present study was to evaluate the effects of WBE on the markers of CRC risk in healthy volunteers, and to correlate these effects with colonic fermentation. A total of twenty healthy subjects were enrolled in a double-blind, cross-over, randomised, controlled trial in which the subjects ingested WBE (10 g/d) or placebo (maltodextrin, 10 g/d) for 3 weeks, separated by a 3-week washout period. At the end of each study period, colonic handling of NH3 was evaluated using the biomarker lactose[15N, 15N']ureide, colonic fermentation was characterised through a metabolomics approach, and the predominant microbial composition was analysed using denaturing gradient gel electrophoresis. As markers of CRC risk, faecal water genotoxicity was determined using the comet assay and faecal water cytotoxicity using a colorimetric cell viability assay. Intake of WBE induced a shift from urinary to faecal 15N excretion, indicating a stimulation of colonic bacterial activity and/or growth. Microbial analysis revealed a selective stimulation of Bifidobacterium adolescentis. In addition, WBE altered the colonic fermentation pattern and significantly reduced colonic protein fermentation compared with the run-in period. However, faecal water cytotoxicity and genotoxicity were not affected. Although intake of WBE clearly affected colonic fermentation and changed the composition of the microbiota, these changes were not associated with the changes in the markers of CRC risk.

  8. Production of Functional High-protein Beverage Fermented with Lactic Acid Bacteria Isolated from Korean Traditional Fermented Food

    PubMed Central

    2015-01-01

    The aim of this study was to manufacture functional high protein fermented beverage, using whey protein concentrate (WPC) and Lactobacillus plantarum DK211 isolated from kimchi, and to evaluate the physicochemical, functional, and sensory properties of the resulting product. The fermented whey beverage (FWB) was formulated with whey protein concentrate 80 (WPC 80), skim milk powder, and sucrose; and fermented with Lactobacillus plantarum DK211 as single, or mixed with Lactococcus lactis R704, a commercial starter culture. The pH, titratable acidity, and viable cell counts during fermentation and storage were evaluated. It was found that the mixed culture showed faster acid development than the single culture. The resulting FWB had high protein (9%) and low fat content (0.2%). Increased viscosity, and antioxidant and antimicrobial activity were observed after fermentation. A viable cell count of 109 CFU/mL in FWB was achieved within 10 h fermentation, and it remained throughout storage at 15℃ for 28 d. Sensory analysis was also conducted, and compared to that of a commercial protein drink. The sensory scores of FWB were similar to those of the commercial protein drink in most attributes, except sourness. The sourness was highly related with the high lactic acid content produced during fermentation. The results showed that WPC and vegetable origin lactic acid bacteria isolated from kimchi might be used for the development of a high protein fermented beverage, with improved functionality and organoleptic properties. PMID:26761827

  9. Safety assessment of the biogenic amines in fermented soya beans and fermented bean curd.

    PubMed

    Yang, Juan; Ding, Xiaowen; Qin, Yingrui; Zeng, Yitao

    2014-08-06

    To evaluate the safety of biogenic amines, high performance liquid chromatography (HPLC) was used to evaluate the levels of biogenic amines in fermented soya beans and fermented bean curd. In fermented soya beans, the total biogenic amines content was in a relatively safe range in many samples, although the concentration of histamine, tyramine, and β-phenethylamine was high enough in some samples to cause a possible safety threat, and 8 of the 30 samples were deemed unsafe. In fermented bean curd, the total biogenic amines content was more than 900 mg/kg in 19 white sufu amples, a level that has been determined to pose a safety hazard; putrescine was the only one detected in all samples and also had the highest concentration, which made samples a safety hazard; the content of tryptamine, β-phenethylamine, tyramine, and histamine had reached the level of threat to human health in some white and green sufu samples, and that may imply another potential safety risk; and 25 of the 33 samples were unsafe. In conclusion, the content of biogenic amines in all fermented soya bean products should be studied and appropriate limits determined to ensure the safety of eating these foods.

  10. Use of real time gas production data for more accurate comparison of continuous single-stage and two-stage fermentation.

    PubMed

    Massanet-Nicolau, Jaime; Dinsdale, Richard; Guwy, Alan; Shipley, Gary

    2013-02-01

    Changes in fermenter gas composition within a given 24h period can cause severe bias in calculations of biogas or energy yields based on just one or two measurements of gas composition per day, as is common in other studies of two-stage fermentation. To overcome this bias, real time recording of gas composition and production were used to undertake a detailed and controlled comparison of single-stage and two-stage fermentation using a real world substrate (wheat feed pellets). When a two-stage fermentation system was used, methane yields increased from 261 L kg(-1)VS using a 20 day HRT, single-stage fermentation, to 359 L kg(-1) VS using a two-stage fermentation with the same overall retention time--an increase of 37%. Additionally a hydrogen yield of 7 L kg(-1) VS was obtained when two-stage fermentation was used. The two-stage system could also be operated at a shorter, 12 day HRT and still produce higher methane yields (306 L kg(-1) VS). Both two-stage fermentation systems evaluated exhibited methane yields in excess of that predicted by a biological methane potential test (BMP) performed using the same feedstock (260 L kg(-1)VS). Copyright © 2012 Elsevier Ltd. All rights reserved.

  11. Effect of propionic acid on citric acid fermentation in an integrated citric acid-methane fermentation process.

    PubMed

    Xu, Jian; Bao, Jia-Wei; Su, Xian-Feng; Zhang, Hong-Jian; Zeng, Xin; Tang, Lei; Wang, Ke; Zhang, Jian-Hua; Chen, Xu-Sheng; Mao, Zhong-Gui

    2016-03-01

    In this study, an integrated citric acid-methane fermentation process was established to solve the problem of wastewater treatment in citric acid production. Citric acid wastewater was treated through anaerobic digestion and then the anaerobic digestion effluent (ADE) was further treated and recycled for the next batch citric acid fermentation. This process could eliminate wastewater discharge and reduce water resource consumption. Propionic acid was found in the ADE and its concentration continually increased in recycling. Effect of propionic acid on citric acid fermentation was investigated, and results indicated that influence of propionic acid on citric acid fermentation was contributed to the undissociated form. Citric acid fermentation was inhibited when the concentration of propionic acid was above 2, 4, and 6 mM in initial pH 4.0, 4.5 and, 5.0, respectively. However, low concentration of propionic acid could promote isomaltase activity which converted more isomaltose to available sugar, thereby increasing citric acid production. High concentration of propionic acid could influence the vitality of cell and prolong the lag phase, causing large amount of glucose still remaining in medium at the end of fermentation and decreasing citric acid production.

  12. Structural differences among alkali-soluble arabinoxylans from maize (Zea mays), rice (Oryza sativa), and wheat (Triticum aestivum) brans influence human fecal fermentation profiles.

    PubMed

    Rose, Devin J; Patterson, John A; Hamaker, Bruce R

    2010-01-13

    Human fecal fermentation profiles of maize, rice, and wheat bran and their dietary fiber fractions released by alkaline-hydrogen peroxide treatment (principally arabinoxylan) were obtained with the aim of identifying and characterizing fractions associated with high production of short chain fatty acids and a linear fermentation profile for possible application as a slowly fermentable dietary fiber. The alkali-soluble fraction from maize bran resulted in the highest short chain fatty acid production among all samples tested, and was linear over the 24 h fermentation period. Size-exclusion chromatography and (1)H NMR suggested that higher molecular weight and uniquely substituted arabinose side chains may contribute to these properties. Monosaccharide disappearance data suggest that maize and rice bran arabinoxylans are fermented by a debranching mechanism, while wheat bran arabinoxylans likely contain large unsubstituted xylose regions that are fermented preferentially, followed by poor fermentation of the remaining, highly branched oligosaccharides.

  13. Kinetics model development of cocoa bean fermentation

    NASA Astrophysics Data System (ADS)

    Kresnowati, M. T. A. P.; Gunawan, Agus Yodi; Muliyadini, Winny

    2015-12-01

    Although Indonesia is one of the biggest cocoa beans producers in the world, Indonesian cocoa beans are oftenly of low quality and thereby frequently priced low in the world market. In order to improve the quality, adequate post-harvest cocoa processing techniques are required. Fermentation is the vital stage in series of cocoa beans post harvest processing which could improve the quality of cocoa beans, in particular taste, aroma, and colours. During the fermentation process, combination of microbes grow producing metabolites that serve as the precursors for cocoa beans flavour. Microbial composition and thereby their activities will affect the fermentation performance and influence the properties of cocoa beans. The correlation could be reviewed using a kinetic model that includes unstructured microbial growth, substrate utilization and metabolic product formation. The developed kinetic model could be further used to design cocoa bean fermentation process to meet the expected quality. Further the development of kinetic model of cocoa bean fermentation also serve as a good case study of mixed culture solid state fermentation, that has rarely been studied. This paper presents the development of a kinetic model for solid-state cocoa beans fermentation using an empirical approach. Series of lab scale cocoa bean fermentations, either natural fermentations without starter addition or fermentations with mixed yeast and lactic acid bacteria starter addition, were used for model parameters estimation. The results showed that cocoa beans fermentation can be modelled mathematically and the best model included substrate utilization, microbial growth, metabolites production and its transport. Although the developed model still can not explain the dynamics in microbial population, this model can sufficiently explained the observed changes in sugar concentration as well as metabolic products in the cocoa bean pulp.

  14. Production of polymalic acid and malic acid by Aureobasidium pullulans fermentation and acid hydrolysis.

    PubMed

    Zou, Xiang; Zhou, Yipin; Yang, Shang-Tian

    2013-08-01

    Malic acid is a dicarboxylic acid widely used in the food industry and also a potential C4 platform chemical that can be produced from biomass. However, microbial fermentation for direct malic acid production is limited by low product yield, titer, and productivity due to end-product inhibition. In this work, a novel process for malic acid production from polymalic acid (PMA) fermentation followed by acid hydrolysis was developed. First, a PMA-producing Aureobasidium pullulans strain ZX-10 was screened and isolated. This microbe produced PMA as the major fermentation product at a high-titer equivalent to 87.6 g/L of malic acid and high-productivity of 0.61 g/L h in free-cell fermentation in a stirred-tank bioreactor. Fed-batch fermentations with cells immobilized in a fibrous-bed bioreactor (FBB) achieved the highest product titer of 144.2 g/L and productivity of 0.74 g/L h. The fermentation produced PMA was purified by adsorption with IRA-900 anion-exchange resins, achieving a ∼100% purity and a high recovery rate of 84%. Pure malic acid was then produced from PMA by hydrolysis with 2 M sulfuric acid at 85°C, which followed the first-order reaction kinetics. This process provides an efficient and economical way for PMA and malic acid production, and is promising for industrial application. Copyright © 2013 Wiley Periodicals, Inc.

  15. Characterization of specialized flocculent yeasts to improve sparkling wine fermentation.

    PubMed

    Tofalo, R; Perpetuini, G; Di Gianvito, P; Arfelli, G; Schirone, M; Corsetti, A; Suzzi, G

    2016-06-01

    Flocculent wine yeasts were characterized for the expression of FLO1, FLO5, FLO8, AMN1 and RGA1 genes, growth kinetics and physicochemical properties of the cell surface during a 6-month sparkling wine fermentation period. The expression of FLO1, FLO5, FLO8, AMN1 and RGA1 genes was determined by RT-qPCR. The physicochemical characterization of yeast surface properties was evaluated by the microbial adhesion to solvents method. FLO5 gene was the most expressed one and a linear correlation with the flocculent degree was found. Flocculent strains were more hydrophobic than the commercial wine strain EC1118. Gene expressions and the ability to face secondary wine fermentation conditions were strain dependent. The importance of FLO5 gene in developing the high flocculent characteristic of wine yeasts was highlighted. Cell surface properties depended on the time of fermentation. Better knowledge about the expression of some genes encoding the flocculent phenotype which could be useful to select suitable starter cultures to improve sparkling wine technology was achieved. A step forward in understanding the complexity and strain-specific nature of flocculation phenotype was done. © 2016 The Society for Applied Microbiology.

  16. Marketing EPSDT to Clients: A Self-Instructional Module for Early Periodic Screening Diagnosis Treatment.

    ERIC Educational Resources Information Center

    Simon, John L.; McArdle, Patricia

    Early and Periodic Screening, Diagnosis and Treatment (EPSDT) is a program of preventive health services available to individuals under 21 years of age who are eligible for Medicaid benefits. As of July 1, 1973, all states operating a Medicaid program were required to provide EPSDT services to all those eligible. The purpose of this module is to…

  17. Mindful Persistence: Literacies for Taking up and Sustaining Fermented-Food Projects

    ERIC Educational Resources Information Center

    Santana, Christina; Kuznetsov, Stacey; Schmeckpeper, Sheri; Curry, Linda J.; Long, Elenore; Davis, Lauren; Koerner, Heidi; McQuarrie, Kimberly Butterfield

    2015-01-01

    Almost by definition, resisting the insidious convenience of the mainstream food supply requires persistence. This is especially true for food projects requiring fermentation--projects that unfold over days or weeks and require day-to-day science in kitchens where variables can be hard to control and where some degree of periodic failure is almost…

  18. Recombinant Zymomonas for pentose fermentation

    DOEpatents

    Picataggio, S.K.; Zhang, M.; Eddy, C.K.; Deanda, K.A.; Finkelstein, M.

    1996-05-07

    The invention relates to microorganisms which normally do not ferment a pentose sugar and which are genetically altered to ferment this pentose to produce ethanol. A representative example is Zymomonas mobilis which has been transformed with E. coli xylose isomerase, xylulokinase, transaldolase and transketolase genes. Expression of the added genes are under the control of Zymomonas mobilis promoters. This newly created microorganism is useful for fermenting pentoses and glucose, produced by hydrolysis of hemicellulose and cellulose, to produce ethanol. 2 figs.

  19. Tow steps biohydrogen production: biomass pretreatment and fermentation

    NASA Astrophysics Data System (ADS)

    Ma, C.; Yang, H. H.; Guo, L. J.

    2010-03-01

    This paper investigated the pretreatment of cornstalk and integrated dark-photo fermentation for hydrogen production. Five parameters of the pretreatment experiments, including NaOH concentration, temperature, residence time, and dosage of cellulase and xylanase, were optimized through the L25 (5≙5) orthogonal test. The optimal NaOH concentration, temperature, residence time, and dosage of cellulase and xylanase were 0.5wt%, 115 °C, 3 h, 0.08g/g cornstalk, 0.08g/g cornstalk, respectively. Under the optimal conditions, 0.31g glucose/g cornstalk was obtained. The two-step fermentation consisted of dark fermentation and photo fermentation. The pretreated cornstalk was used as the substrate for dark fermentation, with cow dung as the inoculum. Then the effluents of dark fermentation were employed as the substrate for photo fermentation by photosynthetic bacteria. H2 yield of dark fermentation was 116.7 mL/g cornstalk, with H2 concentration of 41%. After photo fermentation, the total H2 yield increased to 294 mL/g cornstalk.

  20. Effect of mixing during fermentation in yogurt manufacturing.

    PubMed

    Aguirre-Ezkauriatza, E J; Galarza-González, M G; Uribe-Bujanda, A I; Ríos-Licea, M; López-Pacheco, F; Hernández-Brenes, C M; Alvarez, M M

    2008-12-01

    In traditional yogurt manufacturing, the yogurt is not agitated during fermentation. However, stirring could be beneficial, particularly for improving heat and mass transport across the fermentation tank. In this contribution, we studied the effect of low-speed agitation during fermentation on process time, acidity profile, and microbial dynamics during yogurt fermentation in 2 laboratory-scale fermenters (3 and 5 L) with different heat-transfer characteristics. Lactobacillus bulgaricus and Streptococcus thermophilus were used as fermenting bacteria. Curves of pH, lactic acid concentration, lactose concentration, and bacterial population profiles during fermentation are presented for static and low-agitation conditions during fermentation. At low-inoculum conditions, agitation reduced the processing time by shortening the lag phase. However, mixing did not modify the duration or the shape of the pH profiles during the exponential phase. In fermentors with poor heat-transfer characteristics, important differences in microbial dynamics were observed between the agitated and nonagitated fermentation experiments; that is, agitation significantly increased the observable specific growth rate and the final microbial count of L. bulgaricus.

  1. Comparison of the bacterial species diversity of spontaneous cocoa bean fermentations carried out at selected farms in Ivory Coast and Brazil.

    PubMed

    Papalexandratou, Zoi; Camu, Nicholas; Falony, Gwen; De Vuyst, Luc

    2011-08-01

    To compare the spontaneous cocoa bean fermentation process carried out in different cocoa-producing regions, heap and box (one Ivorian farm) and box (two Brazilian farms) fermentations were carried out. All fermentations were studied through a multiphasic approach. In general, the temperature inside the fermenting mass increased throughout all fermentations and reached end-values of 42-48 °C. The main end-products of pulp carbohydrate catabolism were ethanol, lactic acid, acetic acid, and/or mannitol. In the case of the fermentations on the selected Ivorian farm, the species diversity of lactic acid bacteria (LAB) and acetic acid bacteria (AAB) was restricted. Lactobacillus fermentum and Leuconostoc pseudomesenteroides were the predominant LAB species, due to their ethanol and acid tolerance and citrate consumption. The levels of mannitol, ascribed to growth of L. fermentum, were fermentation-dependent. Also, enterobacterial species, such as Erwinia soli and Pantoea sp., were among the predominating microbiota during the early stages of both heap and box fermentations in Ivory Coast, which could be responsible for gluconic acid production. Consumption of gluconic acid at the initial phases of the Ivorian fermentations could be due to yeast growth. A wider microbial species diversity throughout the fermentation process was seen in the case of the box fermentations on the selected Brazilian farms, which differed, amongst other factors, regarding pod/bean selection on these farms as compared to fermentations on the selected Ivorian farm. This microbiota included Lactobacillus plantarum, Lactobacillus durianis, L. fermentum, Lactobacillus mali, Lactobacillus nagelii, L. pseudomesenteroides, and Pediococcus acidilactici, as well as Bacillus subtilis that was present at late fermentation, when the temperature inside the fermenting mass reached values higher than 50 °C. Moreover, AAB seemed to dominate the Brazilian box fermentations studied, explaining higher acetic

  2. Effects of dietary fibers with different fermentation characteristics on feeding motivation in adult female pigs.

    PubMed

    Souza da Silva, Carol; Bolhuis, J Elizabeth; Gerrits, Walter J J; Kemp, Bas; van den Borne, Joost J G C

    2013-02-17

    Dietary fibers can be fermented in the colon, resulting in production of short-chain fatty acids (SCFA) and secretion of satiety-related peptides. Fermentation characteristics (fermentation kinetics and SCFA-profile) differ between fibers and could impact their satiating potential. We investigated the effects of fibers with varying fermentation characteristics on feeding motivation in adult female pigs. Sixteen pair-housed pigs received four diets in four periods in a Latin square design. Starch from a control (C) diet was exchanged, based on gross energy, for inulin (INU), guar gum (GG), or retrograded tapioca starch (RS), each at a low (L) and a high (H) inclusion level. This resulted in a decreased metabolizable energy intake when feeding fiber diets as compared with the C diet. According to in vitro fermentation measurements, INU is rapidly fermentable and yields relatively high amounts of propionate, GG is moderately rapidly fermentable and yields relatively high amounts of acetate, and RS is slowly fermentable and yields relatively high amounts of butyrate. Feeding motivation was assessed using behavioral tests at 1h, 3h and 7h after the morning meal, and home pen behavioral observations throughout the day. The number of wheel turns paid for a food reward in an operant test was unaffected by diet. Pigs on H-diets ran 25% slower for a food reward in a runway test than pigs on L-diets, and showed less spontaneous physical activity and less stereotypic behavior in the hours before the afternoon meal, reflecting increased interprandial satiety. Reduced feeding motivation with increasing inclusion level was most pronounced for RS, as pigs decreased speed in the runway test and tended to have a lower voluntary food intake in an ad libitum food intake test when fed RS-H. In conclusion, increasing levels of fermentable fibers in the diet seemed to enhance satiety in adult pigs, despite a reduction in metabolizable energy supply. RS was the most satiating fiber

  3. Application of Lactobacillus immobilized by Activated Carbon Fiber in Fermentation of Lactic Acid in Starch Wastewater

    NASA Astrophysics Data System (ADS)

    Xu, Wei; Wang, Peng; Chi, Guoda; Huang, Chenyong

    2010-11-01

    Activated carbon fibers (ACF) as the carrier of Lactobacillus was introduced into fermenting system, and a method of modifying the surface of ACF by HNO3-Fe (III) was established. Factors that affect ACF carrier's effect on immobilization of Lactobacillus were studied. HCl, H2SO4, HNO3 and FeCl3 solutions were respectively used to modify the surface properties of ACF. The amount of Fe (III) carried on ACF surface was 0.1563 mol/kg after ACF surface was modified by HNO3 for 5 h and then by 0.1 mol/L FeCl3 for 4 h, when the thickness of Lactobacillus on a single silk of carrier reached 40 μm. When ACF modified by HNO3-Fe (III) was applied in the fermentation of lactic acid in starch industry wastewater, the fermentation period reduced by 8 h and the output of L-lactic acid was 65.5 g/L, which was 3.3% more than that fermented without the carrier.

  4. Simultaneous fermentation and separation in an immobilized cell trickle bed reactor: Acetone-butanol-ethane (ABE) and ethanol fermentation

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Park, C.H.

    1989-01-01

    A novel process employing immobilized cells and in-situ product removal was studied for acetone-butanol-ethanol (ABE) fermentation by Clostridium acetobutylicum and ethanol fermentation by Saccharomyces cerevisiae. Experimental studies of ABE fermentation in a trickle bed reactor without product separation showed that solvent production could be improved by one order of magnitude compared to conventional batch fermentation. Control of effluent pH near 4.3 and feed glucose concentrations higher than 10 g/L were the necessary conditions for cell growth and solvent production. A mathematical model using an equilibrium staged model predicted efficient separation of butanol from the fermentation broth. Activity coefficients of multicomponentmore » system were estimated by Wilson's equation or the ASOG method. Inhibition by butanol and organic acids was incorporated into the kinetic expression. Experimental performance of simultaneous fermentation and separation in an immobilized cell trickle bed reactor showed that glucose conversion was improved as predicted by mathematical modeling and analysis. The effect of pH and temperature on ethanol fermentation by Saccharomyces cerevisiae was studied in free and immobilized cell reactors. Conditions for the highest glucose conversion, cell viability and least glycerol yield were determined.« less

  5. Fermentation of soluble cello-oligosaccharides by yeasts

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lastick, S.M.; Spindler, D.D.; Grohmann, K.

    1983-02-01

    Yeast strains that ferment cellobiose were examined with respect to fermentation on soluble cellodextrin preparations. Hydrolysis of the fermentation products was followed using thin layer chromatography. Candida and Brettanomyces sp. hydrolyze cellobiose and, at a much lower rate, cellotriose, indicating the presence of ..beta..-glucosidase (EC 3.2.1.21) activity. Enzyme assays conducted on B. clausenii fermentations indicated that the ..beta..-glucosidase remained cell-associated during fermentation. Torulopsis sp. hydrolyzed all of the cello-oligo-saccharides, indicating exoglucanase (EC 3.2.1.91) activity. The exogluconanase, a glycoprotein with an apparent molecular weight of 8.4 x 10/sup 4/ daltons, is exported into the culture medium.

  6. Acetylene fermentation: An Earth-based analog of biological carbon cycling on Titan

    NASA Astrophysics Data System (ADS)

    Miller, L. G.; Baesman, S. M.; Hoeft, S. E.; Kirshtein, J.; Wolf, K.; Voytek, M. A.; Oremland, R. S.

    2009-12-01

    Acetylene (C2H2) is present in part per million quantities in the atmosphere of Titan; conceivably as an intermediate product of methane photolysis. Currently, Earth’s atmosphere contains only trace amounts of C2H2 (~40 pptv), however higher concentrations likely prevailed during the Hadean and early Archean eons (4.5 - 3.5 Ga). We isolated C2H2-fermenting microbes from various aquatic and sedimentary environments. Acetylene fermentation proceeds via acetylene hydratase (AH) through acetaldehyde, which dismutates to ethanol and acetate, and if oxidants are present (e.g., sulfate) eventually to CO2. Thus, the remnants of a C2H2 cycle exists today on Earth but may also occur on Titan and/or Enceladus, both being planetary bodies hypothesized to have liquid water underlying their frozen surfaces. We developed a molecular method for AH by designing PCR primers to target the functional gene in Pelobacter acetylenicus. We used this method to scan new environments for the presence of AH and we employed DNA sequencing of the 16S rRNA gene in order to positively identify pelobacters in environmental samples. Acetylene fermentation was documented in five diverse salt-, fresh-, and ground-water sites. Pelobacter was identified as the genus responsible for acetylene fermentation in some, but not all, of these sites. Successful probing for AH preceded the discovery of acetylene consumption in a contaminated groundwater site, demonstrating the utility of functional gene probing. A pure culture of a C2H2-fermenting pelobacter was obtained from an intertidal mudflat. We also obtained an enrichment culture (co-cultured with a sulfate reducer) from freshwater lake sediments, but neither was pelobacter nor AH detected in this sample, suggesting that an alternative pathway may be involved here. Slurry experiments using these lake sediments either with or without added C2H2 or sulfate showed that sulfate reduction and acetylene fermentation were independent processes. In general, the

  7. Effect of different aging techniques on the polysaccharide and phenolic composition and sensory characteristics of Syrah red wines fermented using different yeast strains.

    PubMed

    del Barrio-Galán, Rubén; Medel-Marabolí, Marcela; Peña-Neira, Álvaro

    2015-07-15

    The effect of high levels of the polysaccharide Saccharomyces cerevisiae yeast strain (HPS) and another conventional yeast strain (FERM) on the polysaccharide and phenolic composition of Syrah red wines during alcoholic fermentation and subsequent aging on lees, with or without oak wood chips, and on inactive dry yeast was investigated. The HPS yeast released higher amounts of polysaccharides during alcoholic fermentation than FERM yeast (485 g L(-1) and 403 g L(-1), respectively) and after the aging period (516 g L(-1) and 500 g L(-1), respectively). The different aging techniques increased the polysaccharide concentration; the concentration was dependent on the aging technique applied. The interaction of the polysaccharides with the phenolic compounds depended on the yeast strain, aging technique, aging period and compound analysed. The HPS wines exhibited better sensory characteristics than the FERM wines after alcoholic fermentation; however, during the aging period, it was difficult to determine which technique produced the best wine due to the interactions of aging technique, aging period and sensory attribute evaluated. Copyright © 2015 Elsevier Ltd. All rights reserved.

  8. Effect of acetic acid on citric acid fermentation in an integrated citric acid-methane fermentation process.

    PubMed

    Xu, Jian; Chen, Yang-Qiu; Zhang, Hong-Jian; Tang, Lei; Wang, Ke; Zhang, Jian-Hua; Chen, Xu-Sheng; Mao, Zhong-Gui

    2014-09-01

    An integrated citric acid-methane fermentation process was proposed to solve the problem of extraction wastewater in citric acid fermentation process. Extraction wastewater was treated by anaerobic digestion and then recycled for the next batch of citric acid fermentation to eliminate wastewater discharge and reduce water resource consumption. Acetic acid as an intermediate product of methane fermentation was present in anaerobic digestion effluent. In this study, the effect of acetic acid on citric acid fermentation was investigated and results showed that lower concentration of acetic acid could promote Aspergillus niger growth and citric acid production. 5-Cyano-2,3-ditolyl tetrazolium chloride (CTC) staining was used to quantify the activity of A. niger cells, and the results suggested that when acetic acid concentration was above 8 mM at initial pH 4.5, the morphology of A. niger became uneven and the part of the cells' activity was significantly reduced, thereby resulting in deceasing of citric acid production. Effects of acetic acid on citric acid fermentation, as influenced by initial pH and cell number in inocula, were also examined. The result indicated that inhibition by acetic acid increased as initial pH declined and was rarely influenced by cell number in inocula.

  9. Simultaneous saccharification and fermentation (SSF) using cellobiose fermenting yeast Brettanomyces custersii

    DOEpatents

    Spindler, D.D.; Grohmann, K.; Wyman, C.E.

    1992-03-31

    A process for producing ethanol from plant biomass includes forming a substrate from the biomass with the substrate including hydrolysates of cellulose and hemicellulose. A species of the yeast Brettanomyces custersii (CBS 5512), which has the ability to ferment both cellobiose and glucose to ethanol, is then selected and isolated. The substrate is inoculated with this yeast, and the inoculated substrate is then fermented under conditions favorable for cell viability and conversion of hydrolysates to ethanol. 2 figs.

  10. Simultaneous saccharification and fermentation (SSF) using cellobiose fermenting yeast Brettanomyces custersii

    DOEpatents

    Spindler, Diane D.; Grohmann, Karel; Wyman, Charles E.

    1992-01-01

    A process for producing ethanol from plant biomass includes forming a substrate from the biomass with the substrate including hydrolysates of cellulose and hemicellulose. A species of the yeast Brettanomyces custersii (CBS 5512), which has the ability to ferment both cellobiose and glucose to ethanol, is then selected and isolated. The substrate is inoculated with this yeast, and the inoculated substrate is then fermented under conditions favorable for cell viability and conversion of hydrolysates to ethanol.

  11. Characteristics of an immobilized yeast cell system using very high gravity for the fermentation of ethanol.

    PubMed

    Ji, Hairui; Yu, Jianliang; Zhang, Xu; Tan, Tianwei

    2012-09-01

    The characteristics of ethanol production by immobilized yeast cells were investigated for both repeated batch fermentation and continuous fermentation. With an initial sugar concentration of 280 g/L during the repeated batch fermentation, more than 98% of total sugar was consumed in 65 h with an average ethanol concentration and ethanol yield of 130.12 g/L and 0.477 g ethanol/g consumed sugar, respectively. The immobilized yeast cell system was reliable for at least 10 batches and for a period of 28 days without accompanying the regeneration of Saccharomyces cerevisiae inside the carriers. The multistage continuous fermentation was carried out in a five-stage column bioreactor with a total working volume of 3.75 L. The bioreactor was operated for 26 days at a dilution rate of 0.015 h(-1). The ethanol concentration of the effluent reached 130.77 g/L ethanol while an average 8.18 g/L residual sugar remained. Due to the high osmotic pressure and toxic ethanol, considerable yeast cells died without regeneration, especially in the last two stages, which led to the breakdown of the whole system of multistage continuous fermentation.

  12. Microbial contamination of fuel ethanol fermentations.

    PubMed

    Beckner, M; Ivey, M L; Phister, T G

    2011-10-01

    Microbial contamination is a pervasive problem in any ethanol fermentation system. These infections can at minimum affect the efficiency of the fermentation and at their worse lead to stuck fermentations causing plants to shut down for cleaning before beginning anew. These delays can result in costly loss of time as well as lead to an increased cost of the final product. Lactic acid bacteria (LAB) are the most common bacterial contaminants found in ethanol production facilities and have been linked to decreased ethanol production during fermentation. Lactobacillus sp. generally predominant as these bacteria are well adapted for survival under high ethanol, low pH and low oxygen conditions found during fermentation. It has been generally accepted that lactobacilli cause inhibition of Saccharomyces sp. and limit ethanol production through two basic methods; either production of lactic and acetic acids or through competition for nutrients. However, a number of researchers have demonstrated that these mechanisms may not completely account for the amount of loss observed and have suggested other means by which bacteria can inhibit yeast growth and ethanol production. While LAB are the primary contaminates of concern in industrial ethanol fermentations, wild yeast may also affect the productivity of these fermentations. Though many yeast species have the ability to thrive in a fermentation environment, Dekkera bruxellensis has been repeatedly targeted and cited as one of the main contaminant yeasts in ethanol production. Though widely studied for its detrimental effects on wine, the specific species-species interactions between D. bruxellensis and S. cerevisiae are still poorly understood. © 2011 The Authors. Letters in Applied Microbiology © 2011 The Society for Applied Microbiology.

  13. Maltotriose fermentation by Saccharomyces cerevisiae.

    PubMed

    Zastrow, C R; Hollatz, C; de Araujo, P S; Stambuk, B U

    2001-07-01

    Maltotriose, the second most abundant sugar of brewer's wort, is not fermented but is respired by several industrial yeast strains. We have isolated a strain capable of growing on a medium containing maltotriose and the respiratory inhibitor, antimycin A. This strain produced equivalent amounts of ethanol from 20 g l(-1) glucose, maltose, or maltotriose. We performed a detailed analysis of the rates of active transport and intracellular hydrolysis of maltotriose by this strain, and by a strain that does not ferment this sugar. The kinetics of sugar hydrolysis by both strains was similar, and our results also indicated that yeast cells do not synthesize a maltotriose-specific alpha-glucosidase. However, when considering active sugar transport, a different pattern was observed. The maltotriose-fermenting strain showed the same rate of active maltose or maltotriose transport, while the strain that could not ferment maltotriose showed a lower rate of maltotriose transport when compared with the rates of active maltose transport. Thus, our results revealed that transport across the plasma membrane, and not intracellular hydrolysis, is the rate-limiting step for the fermentation of maltotriose by these Saccharomyces cerevisiae cells.

  14. Fermentation reactions of Erysipelothrix rhusiopathiae.

    PubMed

    WHITE, T G; SHUMAN, R D

    1961-10-01

    White, Thomas G. (U. S. Department of Agriculture, Ames, Iowa), and Richard D. Shuman. Fermentation reactions of Erysipelothrix rhusiopathiae. J. Bacteriol. 82:595-599. 1961.-A study was made to determine the effect of four different basal media, to which fermentable carbon compounds had been added, upon 22 selected strains of Erysipelothrix rhusiopathiae (insidiosa). Acid production was measured by (i) chemical indicator, (ii) change in pH, and (iii) production of titrable acidity. At least two determinations, usually four, were made for each test on each strain. The fermentation pattern varied according to the medium, the indicator, and the method of measuring acid production. Andrade's base plus serum was the most dependable medium because it permitted the least variation in the total number of different patterns. Of the three methods used to measure acid production, the chemical indicator gave the most valid and reproducible results. The within-strain variation was not extreme and most strains persisted in a given fermentation pattern under like conditions of growth and acid production. Results of the study indicated that, regardless of the medium and indicator routinely used, one should be familiar with the fermentation pattern of known strains of the erysipelas organism.

  15. Fermented dairy products: knowledge and consumption.

    PubMed

    Hekmat, Sharareh; Koba, Lesia

    2006-01-01

    Much has been published on the nutritional and health benefits of fermented dairy products, especially those containing probiotic microorganisms. However, consumers may not be familiar with the term "fermented dairy products," and therefore may not take full advantage of them. University students' knowledge and consumption patterns of fermented dairy products were assessed. University students (n=223) completed a survey consisting of a section on demographics and another on knowledge and consumption patterns. The majority of respondents (62%) were not familiar with the term "fermented dairy products." Most respondents consumed yogourt a few times a week (40%) or a few times a month (30%). Almost all respondents (92%) were unable to identify the difference between regular and probiotic yogourt. Most respondents (93%) had not heard of acidophilus milk, but the majority (65%) would be willing to try it. Most respondents were unsure whether sour cream (65%), yogourt beverages (74%), and cheddar cheese (61%) were fermented dairy products. Sixty percent of respondents never consumed yogourt drinks. Education is needed about fermented dairy products, especially probiotics, and their nutritional and health benefits. Such education may increase their acceptability and consumption.

  16. Concurrent Lactic and Volatile Fatty Acid Analysis of Microbial Fermentation Samples by Gas Chromatography with Heat Pre-treatment.

    PubMed

    Darwin; WipaCharles; Cord-Ruwisch, Ralf

    2018-01-01

    Organic acid analysis of fermentation samples can be readily achieved by gas chromatography (GC), which detects volatile organic acids. However, lactic acid, a key fermentation acid is non-volatile and can hence not be quantified by regular GC analysis. However the addition of periodic acid to organic acid samples has been shown to enable lactic acid analysis by GC, as periodic acid oxidizes lactic acid to the volatile acetaldehyde. Direct GC injection of lactic acid standards and periodic acid generated inconsistent and irreproducible peaks, possibly due to incomplete lactic acid oxidation to acetaldehyde. The described method is developed to improve lactic acid analysis by GC by using a heat treated derivatization pre-treatment, such that it becomes independent of the retention time and temperature selection of the GC injector. Samples containing lactic acid were amended by periodic acid and heated in a sealed test tube at 100°C for at least 45 min before injecting it to the GC. Reproducible and consistent peaks of acetaldehyde were obtained. Simultaneous determination of lactic acid, acetone, ethanol, butanol, volatile fatty acids could also be accomplished by applying this GC method, enabling precise and convenient organic acid analysis of biological samples such as anaerobic digestion and fermentation processes. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  17. Yeast population dynamics of industrial fuel-ethanol fermentation process assessed by PCR-fingerprinting.

    PubMed

    da Silva-Filho, Eurípedes Alves; Brito dos Santos, Scheila Karina; Resende, Alecsandra do Monte; de Morais, José Otamar Falcão; de Morais, Marcos Antonio; Ardaillon Simões, Diogo

    2005-07-01

    Yeast population used in industrial production of fuel-ethanol may vary according to the plant process condition and to the environmental stresses imposed to yeast cells. Therefore, yeast strains isolated from a particular industrial process may be adapted to such conditions and should be used as starter strain instead of less adapted commercial strains. This work reports the use of PCR-fingerprinting method based on microsatellite primer (GTG)5 to characterize the yeast population dynamics along the fermentation period in six distilleries. The results show that indigenous fermenting strains present in the crude substrate can be more adapted to the industrial process than commercial strains. We also identified new strains that dominate the yeast population and were more present either in molasses or sugar cane fermenting distilleries. Those strains were proposed to be used as starters in those industrial processes. This is the first report on the use of molecular markers to discriminate Saccharomyces cerevisiae strains from fuel-ethanol producing process.

  18. Simultaneous Clostridial fermentation, lipase-catalyzed esterification, and ester extraction to enrich diesel with butyl butyrate.

    PubMed

    van den Berg, Corjan; Heeres, Arjan S; van der Wielen, Luuk A M; Straathof, Adrie J J

    2013-01-01

    The recovery of 1-butanol from fermentation broth is energy-intensive since typical concentrations in fermentation broth are below 20 g L(-1). To prevent butanol inhibition and high downstream processing costs, we aimed at producing butyl esters instead of 1-butanol. It is shown that it is possible to perform simultaneously clostridial fermentation, esterification of the formed butanol to butyl butyrate, and extraction of this ester by hexadecane. The very high partition coefficient of butyl butyrate pulls the esterification towards the product side even at fermentation pH and relatively low butanol concentrations. The hexadecane extractant is a model diesel compound and is nontoxic to the cells. If butyl butyrate enriched diesel can directly be used as car fuel, no product recovery is required. A proof-of-principle experiment for the one-pot bio-ester production from glucose led to 5 g L(-1) butyl butyrate in the hexadecane phase. The principle may be extended to a wide range of esters, especially to longer chain ones. Copyright © 2012 Wiley Periodicals, Inc.

  19. Physiological and fermentation properties of Bacillus coagulans and a mutant lacking fermentative lactate dehydrogenase activity.

    PubMed

    Su, Yue; Rhee, Mun Su; Ingram, Lonnie O; Shanmugam, K T

    2011-03-01

    Bacillus coagulans, a sporogenic lactic acid bacterium, grows optimally at 50-55 °C and produces lactic acid as the primary fermentation product from both hexoses and pentoses. The amount of fungal cellulases required for simultaneous saccharification and fermentation (SSF) at 55 °C was previously reported to be three to four times lower than for SSF at the optimum growth temperature for Saccharomyces cerevisiae of 35 °C. An ethanologenic B. coagulans is expected to lower the cellulase loading and production cost of cellulosic ethanol due to SSF at 55 °C. As a first step towards developing B. coagulans as an ethanologenic microbial biocatalyst, activity of the primary fermentation enzyme L-lactate dehydrogenase was removed by mutation (strain Suy27). Strain Suy27 produced ethanol as the main fermentation product from glucose during growth at pH 7.0 (0.33 g ethanol per g glucose fermented). Pyruvate dehydrogenase (PDH) and alcohol dehydrogenase (ADH) acting in series contributed to about 55% of the ethanol produced by this mutant while pyruvate formate lyase and ADH were responsible for the remainder. Due to the absence of PDH activity in B. coagulans during fermentative growth at pH 5.0, the l-ldh mutant failed to grow anaerobically at pH 5.0. Strain Suy27-13, a derivative of the l-ldh mutant strain Suy27, that produced PDH activity during anaerobic growth at pH 5.0 grew at this pH and also produced ethanol as the fermentation product (0.39 g per g glucose). These results show that construction of an ethanologenic B. coagulans requires optimal expression of PDH activity in addition to the removal of the LDH activity to support growth and ethanol production.

  20. Alcoholic Fermentation of d-Xylose by Yeasts

    PubMed Central

    Toivola, Ansa; Yarrow, David; van den Bosch, Eduard; van Dijken, Johannes P.; Scheffers, W. Alexander

    1984-01-01

    Type strains of 200 species of yeasts able to ferment glucose and grow on xylose were screened for fermentation of d-xylose. In most of the strains tested, ethanol production was negligible. Nineteen were found to produce between 0.1 and 1.0 g of ethanol per liter. Strains of the following species produce more than 1 g of ethanol per liter in the fermentation test with 2% xylose: Brettanomyces naardenensis, Candida shehatae, Candida tenuis, Pachysolen tannophilus, Pichia segobiensis, and Pichia stipitis. Subsequent screening of these yeasts for their capacity to ferment d-cellobiose revealed that only Candida tenuis CBS 4435 was a good fermenter of both xylose and cellobiose under the test conditions used. PMID:16346558

  1. Bioethanol production: an integrated process of low substrate loading hydrolysis-high sugars liquid fermentation and solid state fermentation of enzymatic hydrolysis residue.

    PubMed

    Chu, Qiulu; Li, Xin; Ma, Bin; Xu, Yong; Ouyang, Jia; Zhu, Junjun; Yu, Shiyuan; Yong, Qiang

    2012-11-01

    An integrated process of enzymatic hydrolysis and fermentation was investigated for high ethanol production. The combination of enzymatic hydrolysis at low substrate loading, liquid fermentation of high sugars concentration and solid state fermentation of enzymatic hydrolysis residue was beneficial for conversion of steam explosion pretreated corn stover to ethanol. The results suggested that low substrate loading hydrolysis caused a high enzymatic hydrolysis yield; the liquid fermentation of about 200g/L glucose by Saccharomyces cerevisiae provided a high ethanol concentration which could significantly decrease cost of the subsequent ethanol distillation. A solid state fermentation of enzymatic hydrolysis residue was combined, which was available to enhance ethanol production and cellulose-to-ethanol conversion. The results of solid state fermentation demonstrated that the solid state fermentation process accompanied by simultaneous saccharification and fermentation. Copyright © 2012 Elsevier Ltd. All rights reserved.

  2. Fermented and non-fermented soy food consumption and gastric cancer in Japanese and Korean populations: a meta-analysis of observational studies.

    PubMed

    Kim, Jeongseon; Kang, Moonsu; Lee, Jung-Sug; Inoue, Manami; Sasazuki, Shizuka; Tsugane, Shoichiro

    2011-01-01

    Soy food is known to contribute greatly to a reduction in the risk of gastric cancer (GC). However, both Japanese and Korean populations have high incidence rates of GC despite the consumption of a wide variety of soy foods. One primary reason is that they consume fermented rather than non-fermented soy foods. In order to assess the varying effects of fermented and non-fermented soy intake on GC risk in these populations, we conducted a meta-analysis of published reports. Twenty studies assessing the effect of the consumption of fermented soy food on GC risk were included, and 17 studies assessing the effect of the consumption of non-fermented soy food on GC risk were included. We found that a high intake of fermented soy foods was significantly associated with an increased risk of GC (odds ratio [OR] = 1.22, 95% confidence interval [CI] = 1.02-1.44, I(2) = 71.48), whereas an increased intake of non-fermented soy foods was significantly associated with a decreased risk of GC (overall summary OR = 0.64, 95% CI = 0.54-0.77, I(2) = 64.27). These findings show that a high level of consumption of non-fermented soy foods, rather than fermented soy foods, is important in reducing GC risk. © 2010 Japanese Cancer Association.

  3. Cell-to-cell contact and antimicrobial peptides play a combined role in the death of Lachanchea thermotolerans during mixed-culture alcoholic fermentation with Saccharomyces cerevisiae.

    PubMed

    Kemsawasd, Varongsiri; Branco, Patrícia; Almeida, Maria Gabriela; Caldeira, Jorge; Albergaria, Helena; Arneborg, Nils

    2015-07-01

    The roles of cell-to-cell contact and antimicrobial peptides in the early death of Lachanchea thermotolerans CBS2803 during anaerobic, mixed-culture fermentations with Saccharomyces cerevisiae S101 were investigated using a commercially available, double-compartment fermentation system separated by cellulose membranes with different pore sizes, i.e. 1000 kDa for mixed- and single-culture fermentations, and 1000 and 3.5-5 kDa for compartmentalized-culture fermentations. SDS-PAGE and gel filtration chromatography were used to determine an antimicrobial peptidic fraction in the fermentations. Our results showed comparable amounts of the antimicrobial peptidic fraction in the inner compartments of the mixed-culture and 1000 kDa compartmentalized-culture fermentations containing L. thermotolerans after 4 days of fermentation, but a lower death rate of L. thermotolerans in the 1000 kDa compartmentalized-culture fermentation than in the mixed-culture fermentation. Furthermore, L. thermotolerans died off even more slowly in the 3.5-5 kDa than in the 1000 kDa compartmentalized-culture fermentation, which coincided with the presence of less of the antimicrobial peptidic fraction in the inner compartment of that fermentation than of the 1000 kDa compartmentalized-culture fermentation. Taken together, these results indicate that the death of L. thermotolerans in mixed cultures with S. cerevisiae is caused by a combination of cell-to-cell contact and antimicrobial peptides. © FEMS 2015. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  4. The Dynamic Microbiota Profile During Pepper (Piper nigrum L.) Peeling by Solid-State Fermentation.

    PubMed

    Hu, Qisong; Zhang, Jiachao; Xu, Chuanbiao; Li, Congfa; Liu, Sixin

    2017-06-01

    White pepper (Piper nigrum L.), a well-known spice, is the main pepper processing product in Hainan province, China. The solid-state method of fermentation can peel pepper in a highly efficient manner and yield high-quality white pepper. In the present study, we used next-generation sequencing to reveal the dynamic changes in the microbiota during pepper peeling by solid-state fermentation. The results suggested that the inoculated Aspergillus niger was dominant throughout the fermentation stage, with its strains constituting more than 95% of the fungi present; thus, the fungal community structure was relatively stable. The bacterial community structure fluctuated across different fermentation periods; among the bacteria present, Pseudomonas, Tatumella, Pantoea, Acinetobacter, Lactococcus, and Enterobacter accounted for more than 95% of all bacteria. Based on the correlations among the microbial community, we found that Pseudomonas and Acinetobacter were significantly positively related with A. niger, which showed strong synergy with them. In view of the microbial functional gene analysis, we found that these three bacteria and fungi were closely related to the production of pectin esterase (COG4677) and acetyl xylan esterase (COG3458), the key enzymes for pepper peeling. The present research clarifies the solid-state fermentation method of pepper peeling and lays a theoretical foundation to promote the development of the pepper peeling process and the production of high-quality white pepper.

  5. Volatile Compounds Produced by Lactobacillus paracasei During Oat Fermentation.

    PubMed

    Lee, Sang Mi; Oh, Jieun; Hurh, Byung-Serk; Jeong, Gwi-Hwa; Shin, Young-Keum; Kim, Young-Suk

    2016-12-01

    This study investigated the profiles of volatile compounds produced by Lactobacillus paracasei during oat fermentation using gas chromatography-mass spectrometry coupled with headspace solid-phase microextraction method. A total of 60 compounds, including acids, alcohols, aldehydes, esters, furan derivatives, hydrocarbons, ketones, sulfur-containing compounds, terpenes, and other compounds, were identified in fermented oat. Lipid oxidation products such as 2-pentylfuran, 1-octen-3-ol, hexanal, and nonanal were found to be the main contributors to oat samples fermented by L. paracasei with the level of 2-pentylfuran being the highest. In addition, the contents of ketones, alcohols, acids, and furan derivatives in the oat samples consistently increased with the fermentation time. On the other hand, the contents of degradation products of amino acids, such as 3-methylbutanal, benzaldehyde, acetophenone, dimethyl sulfide, and dimethyl disulfide, decreased in oat samples during fermentation. Principal component analysis (PCA) was applied to discriminate the fermented oat samples according to different fermentation times. The fermented oats were clearly differentiated on PCA plots. The initial fermentation stage was mainly affected by aldehydes, whereas the later samples of fermented oats were strongly associated with acids, alcohols, furan derivatives, and ketones. The application of PCA to data of the volatile profiles revealed that the oat samples fermented by L. paracasei could be distinguished according to fermentation time. © 2016 Institute of Food Technologists®.

  6. Detecting cell lysis using viscosity monitoring in E. coli fermentation to prevent product loss

    PubMed Central

    Newton, Joseph M.; Schofield, Desmond; Vlahopoulou, Joanna

    2016-01-01

    Monitoring the physical or chemical properties of cell broths to infer cell status is often challenging due to the complex nature of the broth. Key factors indicative of cell status include cell density, cell viability, product leakage, and DNA release to the fermentation broth. The rapid and accurate prediction of cell status for hosts with intracellular protein products can minimise product loss due to leakage at the onset of cell lysis in fermentation. This article reports the rheological examination of an industrially relevant E. coli fermentation producing antibody fragments (Fab'). Viscosity monitoring showed an increase in viscosity during the exponential phase in relation to the cell density increase, a relatively flat profile in the stationary phase, followed by a rapid increase which correlated well with product loss, DNA release and loss of cell viability. This phenomenon was observed over several fermentations that a 25% increase in broth viscosity (using induction‐point viscosity as a reference) indicated 10% product loss. Our results suggest that viscosity can accurately detect cell lysis and product leakage in postinduction cell cultures, and can identify cell lysis earlier than several other common fermentation monitoring techniques. This work demonstrates the utility of rapidly monitoring the physical properties of fermentation broths, and that viscosity monitoring has the potential to be a tool for process development to determine the optimal harvest time and minimise product loss. © 2016 The Authors. Biotechnology Progress published by Wiley Periodicals, Inc. on behalf of American Institute of Chemical Engineers, 32:1069–1076, 2016 PMID:27111912

  7. Real-time monitoring of high-gravity corn mash fermentation using in situ raman spectroscopy.

    PubMed

    Gray, Steven R; Peretti, Steven W; Lamb, H Henry

    2013-06-01

    In situ Raman spectroscopy was employed for real-time monitoring of simultaneous saccharification and fermentation (SSF) of corn mash by an industrial strain of Saccharomyces cerevisiae. An accurate univariate calibration model for ethanol was developed based on the very strong 883 cm(-1) C-C stretching band. Multivariate partial least squares (PLS) calibration models for total starch, dextrins, maltotriose, maltose, glucose, and ethanol were developed using data from eight batch fermentations and validated using predictions for a separate batch. The starch, ethanol, and dextrins models showed significant prediction improvement when the calibration data were divided into separate high- and low-concentration sets. Collinearity between the ethanol and starch models was avoided by excluding regions containing strong ethanol peaks from the starch model and, conversely, excluding regions containing strong saccharide peaks from the ethanol model. The two-set calibration models for starch (R(2)  = 0.998, percent error = 2.5%) and ethanol (R(2)  = 0.999, percent error = 2.1%) provide more accurate predictions than any previously published spectroscopic models. Glucose, maltose, and maltotriose are modeled to accuracy comparable to previous work on less complex fermentation processes. Our results demonstrate that Raman spectroscopy is capable of real time in situ monitoring of a complex industrial biomass fermentation. To our knowledge, this is the first PLS-based chemometric modeling of corn mash fermentation under typical industrial conditions, and the first Raman-based monitoring of a fermentation process with glucose, oligosaccharides and polysaccharides present. Copyright © 2013 Wiley Periodicals, Inc.

  8. Starter cultures for kimchi fermentation.

    PubMed

    Lee, Mo-Eun; Jang, Ja-Young; Lee, Jong-Hee; Park, Hae-Woong; Choi, Hak-Jong; Kim, Tae-Woon

    2015-05-01

    Kimchi is a traditional Korean vegetable product that is naturally fermented by various microorganisms present in the raw materials. Among these microorganisms, lactic acid bacteria dominate the fermentation process. Natural fermentation with unsterilized raw materials leads to the growth of various lactic acid bacteria, resulting in variations in the taste and quality of kimchi, which may make it difficult to produce industrial-scale kimchi with consistent quality. The use of starter cultures has been considered as an alternative for the industrial production of standardized kimchi, and recent trends suggest that the demand for starter cultures is on the rise. However, several factors should be carefully considered for the successful application of starter cultures for kimchi fermentation. In this review, we summarize recent studies on kimchi starter cultures, describe practical problems in the application of industrial-scale kimchi production, and discuss the directions for further studies.

  9. Assessment of the yeast species composition of cocoa bean fermentations in different cocoa-producing regions using denaturing gradient gel electrophoresis.

    PubMed

    Papalexandratou, Zoi; De Vuyst, Luc

    2011-11-01

    The yeast species composition of 12 cocoa bean fermentations carried out in Brazil, Ecuador, Ivory Coast and Malaysia was investigated culture-independently. Denaturing gradient gel electrophoresis of 26S rRNA gene fragments, obtained through polymerase chain reaction with universal eukaryotic primers, was carried out with two different commercial apparatus (the DCode and CBS systems). In general, this molecular method allowed a rapid monitoring of the yeast species prevailing during fermentation. Under similar and optimal denaturing gradient gel electrophoresis conditions, the CBS system allowed a better separated band pattern than the DCode system and an unambiguous detection of the prevailing species present in the fermentation samples. The most frequent yeast species were Hanseniaspora sp., followed by Pichia kudriavzevii and Saccharomyces cerevisiae, independent of the origin of the cocoa. This indicates a restricted yeast species composition of the cocoa bean fermentation process. Exceptionally, the Ivorian cocoa bean box fermentation samples showed a wider yeast species composition, with Hyphopichia burtonii and Meyerozyma caribbica among the main representatives. Yeasts were not detected in the samples when the temperature inside the fermenting cocoa pulp-bean mass reached values higher than 45 °C or under early acetic acid production conditions. © 2011 Federation of European Microbiological Societies. Published by Blackwell Publishing Ltd. All rights reserved.

  10. Detection of diazotrophy in the acetylene-fermenting anaerobe Pelobacter sp. strain SFB93

    USGS Publications Warehouse

    Akob, Denise M.; Baesman, Shaun; Sutton, John M.; Fierst, Janna L.; Mumford, Adam; Shrestha, Yesha; Poret-Peterson, Amisha T.; Bennett, Stacy; Dunlap, Darren S.; Haase, Karl B.; Oremland, Ronald S.

    2017-01-01

    Acetylene (C2H2) is a trace constituent of the present Earth's oxidizing atmosphere, reflecting a mixture of terrestrial and marine emissions from anthropogenic, biomass-burning, and unidentified biogenic sources. Fermentation of acetylene was serendipitously discovered during C2H2 block assays of N2O reductase, and Pelobacter acetylenicus was shown to grow on C2H2 via acetylene hydratase (AH). AH is a W-containing, catabolic, low-redox-potential enzyme that, unlike nitrogenase (N2ase), is specific for acetylene. Acetylene fermentation is a rare metabolic process that is well characterized only in P. acetylenicus DSM3246 and DSM3247 and Pelobacter sp. strain SFB93. To better understand the genetic controls for AH activity, we sequenced the genomes of the three acetylene-fermenting Pelobacter strains. Genome assembly and annotation produced three novel genomes containing gene sequences for AH, with two copies being present in SFB93. In addition, gene sequences for all five compulsory genes for iron-molybdenum N2ase were also present in the three genomes, indicating the cooccurrence of two acetylene transformation pathways. Nitrogen fixation growth assays showed that DSM3426 could ferment acetylene in the absence of ammonium, but no ethylene was produced. However, SFB93 degraded acetylene and, in the absence of ammonium, produced ethylene, indicating an active N2ase. Diazotrophic growth was observed under N2 but not in experimental controls incubated under argon. SFB93 exhibits acetylene fermentation and nitrogen fixation, the only known biochemical mechanisms for acetylene transformation. Our results indicate complex interactions between N2ase and AH and suggest novel evolutionary pathways for these relic enzymes from early Earth to modern days.

  11. Identification of potential probiotic starter cultures for Scandinavian-type fermented sausages.

    PubMed

    Klingberg, Trine Danø; Axelsson, Lars; Naterstad, Kristine; Elsser, Dieter; Budde, Birgitte Bjørn

    2005-12-15

    Potential probiotic cultures suitable as starter cultures for the Scandinavian-type fermented sausages were identified among strains well-adapted to fermented meats as well as strains originating from a culture collection. From 15 different fermented meat products, 22 strains were isolated as dominant non-starter lactic acid bacteria (NSLAB). The isolates were identified by RAPD, API and sequence analysis of 16S rRNA and showed to be five strains of Lactobacillus sakei, five strains of Lactobacillus farciminis, five strains belonging to the group of Lactobacillus plantarum/pentosus, four strains of Lactobacillus alimentarius, two strains of Lactobacillus brevis and one strain of Lactobacillus versmoldensis. Heterofermentative strains as well as strains not growing at 37 degrees C and not lowering pH below 5.1 in a meat model were excluded leaving 9 strains for further studies. These strains together with 19 strains from a culture collection were evaluated by in vitro methods including survival upon exposure to pH 2.5 or 0.3% oxgall and adhesion to the human colon adenocarcinoma cell line Caco-2 as well as antimicrobial activity against potential pathogens. Strains that fulfilled all the probiotic criteria and showed to be fast acid producers in a meat model included three strains belonging to the group of Lb. plantarum/pentosus (MF1291, MF1298, MF1300) which originated from the dominant NSLAB of fermented meat products. MF1291 and MF 1298 were further identified as Lb. plantarum and MF1300 as Lb. pentosus. The three strains were all successfully applied as starter cultures for the production of fermented sausage. The viable count at the end of the processing period reached high cell numbers (4.7x10(7)-2.9x10(8) cfu/g) and pH of the sausages decreased to pH 4.8-4.9 without any flavour deviation compared to sausage fermented by a commercial meat starter culture.

  12. Incidence and distribution of filamentous fungi during fermentation, drying and storage of coffee (Coffea arabica L.) beans

    PubMed Central

    Silva, Cristina Ferreira; Batista, Luis Roberto; Schwan, Rosane Freitas

    2008-01-01

    The objective of this work was to isolate and characterize filamentous fungi present in different stages of harvest, fermentation, drying and storage of coffee beans processed by natural method. The cherries were hand-picked and then placed on a cement drying platform where they remained until reached 11% of humidity. Microbial counts were found in all samples during fermentation and drying of the coffee beans. Counts of fungi in the coffee cherries collected from the tree (time 0) were around 1.5 x 103 CFU/g. This number increased slowly during the fermentation and drying reaching values of 2 x 105 CFU/g within 22 days of processing. Two hundred and sixty three isolates of filamentous fungi were identified. The distribution of species during fermentation and drying was very varied while there was a predominance of Aspergillus species during storage period. The genera found were Pestalotia (4), Paecelomyces (4), Cladosporium (26), Fusarium (34), Penicillium (81) and Aspergillus (112) and comprised 38 different species. PMID:24031259

  13. Nutritional Guidelines and Fermented Food Frameworks

    PubMed Central

    Bell, Victoria; Ferrão, Jorge; Fernandes, Tito

    2017-01-01

    This review examines different nutritional guidelines, some case studies, and provides insights and discrepancies, in the regulatory framework of Food Safety Management of some of the world’s economies. There are thousands of fermented foods and beverages, although the intention was not to review them but check their traditional and cultural value, and if they are still lacking to be classed as a category on different national food guides. For understanding the inconsistencies in claims of concerning fermented foods among various regulatory systems, each legal system should be considered unique. Fermented foods and beverages have long been a part of the human diet, and with further supplementation of probiotic microbes, in some cases, they offer nutritional and health attributes worthy of recommendation of regular consumption. Despite the impact of fermented foods and beverages on gastro-intestinal wellbeing and diseases, their many health benefits or recommended consumption has not been widely translated to global inclusion in world food guidelines. In general, the approach of the legal systems is broadly consistent and their structures may be presented under different formats. African traditional fermented products are briefly mentioned enhancing some recorded adverse effects. Knowing the general benefits of traditional and supplemented fermented foods, they should be a daily item on most national food guides. PMID:28783111

  14. Phenolic profile and fermentation patterns of different commercial gluten-free pasta during in vitro large intestine fermentation.

    PubMed

    Rocchetti, Gabriele; Lucini, Luigi; Chiodelli, Giulia; Giuberti, Gianluca; Gallo, Antonio; Masoero, Francesco; Trevisan, Marco

    2017-07-01

    The fate of phenolic compounds, along with short-chain fatty acids (SCFAs) production kinetics, was evaluated on six different commercial gluten-free (GF) pasta samples varying in ingredient compositions, focussing on the in vitro faecal fermentation after the gastrointestinal digestion. A general reduction of both total phenolics and reducing power was observed in all samples, together with a substantial change in phenolic profile over 24h of faecal fermentation, with differences among GF pasta samples. Flavonoids, hydroxycinnamics and lignans degraded over time, with a concurrent increase in low-molecular-weight phenolic acids (hydroxybenzoic acids), alkylphenols, hydroxybenzoketones and tyrosols. Interestingly, discriminant analysis also identified several alkyl derivatives of resorcinol as markers of the changes in phenolic profile during in vitro fermentation. Furthermore, degradation pathways of phenolics by intestinal microbiota have been proposed. Considering the total SCFAs and butyrate production during the in vitro fermentation, different fermentation kinetics were observed among GF pasta post-hydrolysis residues. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. Screening of Functional Rhizopus stolonifer for Alcohol Fermentation and Production of High Quality Korean Traditional Rice Wine

    PubMed Central

    Song, Jung-Hwa; Kim, Jae-Ho; Ahn, Byung-Hak

    2010-01-01

    Different strains of mold were screened for the production of high quality Korean traditional rice wine with anti-hypertension and good acceptability. We isolated 867 nuruk mold strains and selected 24 for further study based on measurement of amylase activity. Among them, mold No. 17 showed high ethanol production upon fermentation with Saccharomyces cerevisiae as well as anti-hypertensive properties. The No. 17 strain was therefore selected as the functional mold and later identified as Rhizopus stolonifer based on molecular biological characteristics. Optimal fermentation conditions for the brewing of anti-hypertensive traditional rice wine comprised the addition of R. stolonifer No. 17 koji at a concentration of 35 sp/g and a fermentation period of 10 days at 25℃ using S. cerevisiae. PMID:23956639

  16. Screening of Functional Rhizopus stolonifer for Alcohol Fermentation and Production of High Quality Korean Traditional Rice Wine.

    PubMed

    Song, Jung-Hwa; Kim, Jae-Ho; Ahn, Byung-Hak; Lee, Jong-Soo

    2010-06-01

    Different strains of mold were screened for the production of high quality Korean traditional rice wine with anti-hypertension and good acceptability. We isolated 867 nuruk mold strains and selected 24 for further study based on measurement of amylase activity. Among them, mold No. 17 showed high ethanol production upon fermentation with Saccharomyces cerevisiae as well as anti-hypertensive properties. The No. 17 strain was therefore selected as the functional mold and later identified as Rhizopus stolonifer based on molecular biological characteristics. Optimal fermentation conditions for the brewing of anti-hypertensive traditional rice wine comprised the addition of R. stolonifer No. 17 koji at a concentration of 35 sp/g and a fermentation period of 10 days at 25℃ using S. cerevisiae.

  17. FERMENTATION REACTIONS OF ERYSIPELOTHRIX RHUSIOPATHIAE

    PubMed Central

    White, Thomas G.; Shuman, Richard D.

    1961-01-01

    White, Thomas G. (U. S. Department of Agriculture, Ames, Iowa), and Richard D. Shuman. Fermentation reactions of Erysipelothrix rhusiopathiae. J. Bacteriol. 82:595–599. 1961.—A study was made to determine the effect of four different basal media, to which fermentable carbon compounds had been added, upon 22 selected strains of Erysipelothrix rhusiopathiae (insidiosa). Acid production was measured by (i) chemical indicator, (ii) change in pH, and (iii) production of titrable acidity. At least two determinations, usually four, were made for each test on each strain. The fermentation pattern varied according to the medium, the indicator, and the method of measuring acid production. Andrade's base plus serum was the most dependable medium because it permitted the least variation in the total number of different patterns. Of the three methods used to measure acid production, the chemical indicator gave the most valid and reproducible results. The within-strain variation was not extreme and most strains persisted in a given fermentation pattern under like conditions of growth and acid production. Results of the study indicated that, regardless of the medium and indicator routinely used, one should be familiar with the fermentation pattern of known strains of the erysipelas organism. PMID:14006576

  18. Early adaptation to oxygen is key to the industrially important traits of Lactococcus lactis ssp. cremoris during milk fermentation.

    PubMed

    Cretenet, Marina; Le Gall, Gwenaëlle; Wegmann, Udo; Even, Sergine; Shearman, Claire; Stentz, Régis; Jeanson, Sophie

    2014-12-03

    Lactococcus lactis is the most used species in the dairy industry. Its ability to adapt to technological stresses, such as oxidative stress encountered during stirring in the first stages of the cheese-making process, is a key factor to measure its technological performance. This study aimed to understand the response to oxidative stress of Lactococcus lactis subsp. cremoris MG1363 at the transcriptional and metabolic levels in relation to acidification kinetics and growth conditions, especially at an early stage of growth. For those purposes, conditions of hyper-oxygenation were initially fixed for the fermentation. Kinetics of growth and acidification were not affected by the presence of oxygen, indicating a high resistance to oxygen of the L. lactis MG1363 strain. Its resistance was explained by an efficient consumption of oxygen within the first 4 hours of culture, leading to a drop of the redox potential. The efficient consumption of oxygen by the L. lactis MG1363 strain was supported by a coherent and early adaptation to oxygen after 1 hour of culture at both gene expression and metabolic levels. In oxygen metabolism, the over-expression of all the genes of the nrd (ribonucleotide reductases) operon or fhu (ferrichrome ABC transports) genes was particularly significant. In carbon metabolism, the presence of oxygen led to an early shift at the gene level in the pyruvate pathway towards the acetate/2,3-butanediol pathway confirmed by the kinetics of metabolite production. Finally, the MG1363 strain was no longer able to consume oxygen in the stationary growth phase, leading to a drastic loss of culturability as a consequence of cumulative stresses and the absence of gene adaptation at this stage. Combining metabolic and transcriptomic profiling, together with oxygen consumption kinetics, yielded new insights into the whole genome adaptation of L. lactis to initial oxidative stress. An early and transitional adaptation to oxidative stress was revealed for L

  19. Risk of Porphyromonas gingivalis recolonization during the early period of periodontal maintenance in initially severe periodontitis sites.

    PubMed

    Fujise, Osamu; Miura, Mayumi; Hamachi, Takafumi; Maeda, Katsumasa

    2006-08-01

    Porphyromonas gingivalis is considered a critical pathogen of periodontal diseases including recurrent periodontitis. The profound effects of active periodontal treatment (APT) on P. gingivalis elimination were previously demonstrated and revealed that the subsequent P. gingivalis-free or -suppressed status seems to be maintained during early periodontal maintenance (PMT). The aim of the present study was to show the occurrence of microbial recolonization during this early PMT period. In total, 128 sites from 11 generalized chronic periodontitis patients and one generalized aggressive periodontitis patient underwent clinical and microbiologic examination at baseline (Exam-I), after APT (Exam-II), and in PMT (Exam-III). Exam-III was carried out an average of 4.5 +/- 3.5 months after Exam-II. Detection and quantification of putative pathogens were performed using a polymerase chain reaction-based method. The PMT used was effective in maintaining the clinical conditions improved by APT. However, in microbiological examinations, Exam-III showed higher detection frequency and levels of P. gingivalis than Exam-II. This suggests that a P. gingivalis recolonization started in the early PMT period. P. gingivalis-increased sites then showed significantly more severe signs of periodontitis in Exam-I than P. gingivalis-stable sites (bleeding on probing frequency: 76.7% versus 56.5%; suppuration frequency: 41.9% versus 12.9%). On the other hand, in Exam-II, no significant differences of clinical parameters were noted between P. gingivalis-increased and -stable sites. Severe periodontitis sites before APT seemed to place them at risk of P. gingivalis recolonization in the early PMT period, and this microbial restoration could be a cause of recurrent periodontitis.

  20. 27 CFR 24.212 - High fermentation wine.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ..., DEPARTMENT OF THE TREASURY LIQUORS WINE Production of Other Than Standard Wine § 24.212 High fermentation wine. High fermentation wine is wine made with the addition of sugar within the limitations prescribed... 27 Alcohol, Tobacco Products and Firearms 1 2011-04-01 2011-04-01 false High fermentation wine. 24...

  1. 27 CFR 24.212 - High fermentation wine.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ..., DEPARTMENT OF THE TREASURY ALCOHOL WINE Production of Other Than Standard Wine § 24.212 High fermentation wine. High fermentation wine is wine made with the addition of sugar within the limitations prescribed... 27 Alcohol, Tobacco Products and Firearms 1 2013-04-01 2013-04-01 false High fermentation wine. 24...

  2. 27 CFR 24.212 - High fermentation wine.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ..., DEPARTMENT OF THE TREASURY ALCOHOL WINE Production of Other Than Standard Wine § 24.212 High fermentation wine. High fermentation wine is wine made with the addition of sugar within the limitations prescribed... 27 Alcohol, Tobacco Products and Firearms 1 2014-04-01 2014-04-01 false High fermentation wine. 24...

  3. 27 CFR 24.212 - High fermentation wine.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ..., DEPARTMENT OF THE TREASURY LIQUORS WINE Production of Other Than Standard Wine § 24.212 High fermentation wine. High fermentation wine is wine made with the addition of sugar within the limitations prescribed... 27 Alcohol, Tobacco Products and Firearms 1 2012-04-01 2012-04-01 false High fermentation wine. 24...

  4. 27 CFR 24.212 - High fermentation wine.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false High fermentation wine. 24..., DEPARTMENT OF THE TREASURY LIQUORS WINE Production of Other Than Standard Wine § 24.212 High fermentation wine. High fermentation wine is wine made with the addition of sugar within the limitations prescribed...

  5. Is the Predictability of New-Onset Postpartum Depression Better During Pregnancy or in the Early Postpartum Period? A Prospective Study in Croatian Women.

    PubMed

    Nakić Radoš, Sandra; Herman, Radoslav; Tadinac, Meri

    2016-01-01

    The researchers' aim was to examine whether it was better to predict new-onset postpartum depression (PPD) during pregnancy or immediately after childbirth. A prospective study conducted in Croatia followed women (N = 272) from the third trimester of pregnancy through the early postpartum period (within the first 3 postpartum days), to 6 weeks postpartum. Questionnaires on depression, anxiety, stress, coping, self-esteem, and social support were administered. Through regression analyses we showed that PPD symptoms could be equally predicted by variables from pregnancy (30.3%) and the early postpartum period (34.0%), with a small advantage of PPD prediction in the early postpartum period.

  6. Growth in early life and the development of obesity by age 9 years: are there critical periods and a role for an early life stressor?

    PubMed

    Giles, L C; Whitrow, M J; Rumbold, A R; Davies, C E; de Stavola, B; Pitcher, J B; Davies, M J; Moore, V M

    2013-04-01

    Rapid growth, possibly occurring in critical periods in early life, may be important for the development of obesity. It is unknown whether this is influenced by postnatal exposures such as age-relevant sources of stress. Frequent house moves may be one such stressor. We aimed to examine if there is a period of growth in early life critical for the development of child obesity by age 9 years and assess the role of house moves in modifying any relationships between early life growth and obesity at age 9 years. Prospective Australian birth cohort study. In all, 392 children with serial body size measurements from birth to age 9 years. Standardized body mass index (z-BMI) was available for six time points (spanning birth to 3½ years), and the total number of house moves between birth and 3½ years. The outcomes considered were z-BMI and % body fat (%BF) at age 9 years. Linear regression models were used to estimate the effects of serial measurements of z-BMI and number of house moves on the outcomes. Life-course plots showed that z-BMI at 3½ years was a statistically significant predictor of z-BMI at 9 years (β=0.80; standard error (s.e.), 0.04), whereas z-BMI at 9 months (β=-1.13; s.e., 0.40) and 3½ years (β=4.82; s.e., 0.42) were significant predictors of %BF at age 9 years. There were statistically significant interactions between the number of house moves and change in z-BMI between 9 and 12 months, such that ≥ 3 house moves in early life amplified the detrimental effects of earlier rapid growth on both body size and composition at age 9 years. In the absence of evidence for a single critical period, efforts to prevent overweight and obesity are required throughout childhood. In addition, modifiable postnatal stressors may exacerbate effects of early growth on obesity in later childhood.

  7. The interactive effect of fungicide residues and yeast assimilable nitrogen on fermentation kinetics and hydrogen sulfide production during cider fermentation.

    PubMed

    Boudreau, Thomas F; Peck, Gregory M; O'Keefe, Sean F; Stewart, Amanda C

    2017-01-01

    Fungicide residues on fruit may adversely affect yeast during cider fermentation, leading to sluggish or stuck fermentation or the production of hydrogen sulfide (H 2 S), which is an undesirable aroma compound. This phenomenon has been studied in grape fermentation but not in apple fermentation. Low nitrogen availability, which is characteristic of apples, may further exacerbate the effects of fungicides on yeast during fermentation. The present study explored the effects of three fungicides: elemental sulfur (S 0 ) (known to result in increased H 2 S in wine); fenbuconazole (used in orchards but not vineyards); and fludioxonil (used in post-harvest storage of apples). Only S 0 led to increased H 2 S production. Fenbuconazole (≥0.2 mg L -1 ) resulted in a decreased fermentation rate and increased residual sugar. An interactive effect of yeast assimilable nitrogen (YAN) concentration and fenbuconazole was observed such that increasing the YAN concentration alleviated the negative effects of fenbuconazole on fermentation kinetics. Cidermakers should be aware that residual fenbuconazole (as low as 0.2 mg L -1 ) in apple juice may lead to stuck fermentation, especially when the YAN concentration is below 250 mg L -1 . These results indicate that fermentation problems attributed to low YAN may be caused or exacerbated by additional factors such as fungicide residues, which have a greater impact on fermentation performance under low YAN conditions. © 2016 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. © 2016 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

  8. Influence of Lactobacillus plantarum on yogurt fermentation properties and subsequent changes during postfermentation storage.

    PubMed

    Li, Changkun; Song, Jihong; Kwok, Lai-Yu; Wang, Jicheng; Dong, Yan; Yu, Haijing; Hou, Qiangchuan; Zhang, Heping; Chen, Yongfu

    2017-04-01

    This study aimed to evaluate the influence of 9 Lactobacillusplantarum with broad-spectrum antibacterial activity on fermented milk, including changes to the fermentation characteristics (pH, titration acidity, and viable counts), texture profile, relative content of volatile compounds, and sensory evaluation during 28-d storage at 4°C. First, L. plantarum IMAU80106, IMAU10216, and IMAU70095 were selected as candidates for further study because of their excellent coagulation and proteolytic activities. Subsequently, these L. plantarum strainswere supplemented to fermented milk produced by commercial yogurt starters (Streptococcus thermophilus and Lactobacillus delbrueckii ssp. bulgaricus) and a panel of parameters reflecting product quality was subsequently monitored during 28 d of postfermentation storage. The pH value and titration acidity of the fermented milk mildly fluctuated, whereas the L. plantarum viable counts remained stable along the storage period. Fourteen key volatile compounds were detected in the fermented milk by gas chromatography-mass spectrometry, and some flavor compounds were uniquely present in the L. plantarum-supplemented fermented milk (including 2,3-pentanedione, acetaldehyde, and acetate). No significant difference was shown in the sensory evaluation scores between samples with or without L. plantarum supplementation, but a gradual decrease was observed over storage in all samples. However, when L. plantarum was added, apparent shifts were observed in the overall quality of the fermented milk based on principal component analysis and multivariate ANOVA, particularly in the texture (adhesiveness) and volatile flavor compound profiles (acetaldehyde). Compared with L. plantarum IMAU80106 and IMAU10216, both the texture and volatile flavor profiles of IMAU70095 were closest to those of the control without adding the adjunct bacteria, suggesting that IMAU70095 might be the most suitable strain for further application in functional dairy

  9. LPMOs in cellulase mixtures affect fermentation strategies for lactic acid production from lignocellulosic biomass.

    PubMed

    Müller, Gerdt; Kalyani, Dayanand Chandrahas; Horn, Svein Jarle

    2017-03-01

    Enzymatic catalysis plays a key role in the conversion of lignocellulosic biomass to fuels and chemicals such as lactic acid. In the last decade, the efficiency of commercial cellulase cocktails has increased significantly, in part due to the inclusion of lytic polysaccharide monooxygenases (LPMOs). However, the LPMOs' need for molecular oxygen to break down cellulose demands reinvestigations of process conditions. In this study, we evaluate the efficiency of lactic acid production from steam-exploded birch using an LPMO-containing cellulase cocktail in combination with lactic acid bacteria, investigating both separate hydrolysis and fermentation (SHF) and simultaneous saccharification and fermentation (SSF). While the SSF set up generally has been considered to be more efficient because it avoids sugar accumulation which may inhibit the cellulases, the SHF set up in our study yielded 26-32% more lactic acid than the SSF. This was mainly due to competition for oxygen between LPMOs and the fermenting organisms in the SSF process, which resulted in reduced LPMO activity and thus less efficient saccharification of the lignocellulosic substrate. By means of aeration it was possible to activate the LPMOs in the SSF, but less lactic acid was produced due to a shift in metabolic pathways toward production of acetic acid. Overall, this study shows that lactic acid can be produced efficiently from lignocellulosic biomass, but that the use of LPMO-containing cellulase cocktails in fermentation processes demands re-thinking of traditional process set ups due to the requirement of oxygen in the saccharification step. Biotechnol. Bioeng. 2017;114: 552-559. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  10. Fermentation broth components influence droplet coalescence and hinder advanced biofuel recovery during fermentation.

    PubMed

    Heeres, Arjan S; Schroën, Karin; Heijnen, Joseph J; van der Wielen, Luuk A M; Cuellar, Maria C

    2015-08-01

    Developments in synthetic biology enabled the microbial production of long chain hydrocarbons, which can be used as advanced biofuels in aviation or transportation. Currently, these fuels are not economically competitive due to their production costs. The current process offers room for improvement: by utilizing lignocellulosic feedstock, increasing microbial yields, and using cheaper process technology. Gravity separation is an example of the latter, for which droplet growth by coalescence is crucial. The aim of this study was to study the effect of fermentation broth components on droplet coalescence. Droplet coalescence was measured using two setups: a microfluidic chip and regular laboratory scale stirred vessel (2 L). Some fermentation broth components had a large impact on droplet coalescence. Especially components present in hydrolysed cellulosic biomass and mannoproteins from the yeast cell wall retard coalescence. To achieve a technically feasible gravity separation that can be integrated with the fermentation, the negative effects of these components on coalescence should be minimized. This could be achieved by redesign of the fermentation medium or adjusting the fermentation conditions, aiming to minimize the release of surface active components by the microorganisms. This way, another step can be made towards economically feasible advanced biofuel production. © 2015 The Authors. Biotechnology Journal published by Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim. This is an open access article under the terms of the Creative Commons Attribution-Non-Commercial-NoDerivs Licence, which permits use and distribution in any medium, provided the original work is properly cited, the use is non-commercial and no modifications or adaptations are made.

  11. Characterization of the microbial diversity in yacon spontaneous fermentation

    PubMed Central

    Reina, L. D.; Pérez-Díaz, I. M.; Breidt, F.; Azcarate-Peril, M. A.; Medina, E.; Butz, N.V.

    2015-01-01

    The prebiotic fructooligosaccharides (FOS) content of yacon makes this root an attractive alternative for the supplementation of a variety of food products. The preservation of yacon by fermentation has been proposed as an alternative to increase the probiotic content of the root concomitantly with its shelf life. Thus the fermented yacon could have significant functional content. The objective of this research was to characterize the biochemistry and microbiology of spontaneous yacon fermentation and define the viability of the proposed process. The biochemical analysis of spontaneous heterolactic fermentation of yacon showed a progressive drop in pH with increased lactic and acetic acids, and the production of mannitol during fermentation. The microbial ecology of yacon fermentation was investigated using culture-dependent and culture-independent methods. Bacterial cell counts revealed a dominance of lactic acid bacteria (LAB) over yeasts, which were also present during fermentation. Results showed that the heterofermentative LAB were primarily Leuconostoc species, which dominated the fermentation. The fermentation of yacon by Leuconostoc spp. is thus presented as a viable method to achieve long term preservation of this root. PMID:25777679

  12. Fermentation process for the production of organic acids

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hermann, Theron; Reinhardt, James; Yu, Xiaohui

    This invention relates to improvements in the fermentation process used in the production of organic acids from biological feedstock using bacterial catalysts. The improvements in the fermentation process involve providing a fermentation medium comprising an appropriate form of inorganic carbon, an appropriate amount of aeration and a biocatalyst with an enhanced ability to uptake and assimilate the inorganic carbon into the organic acids. This invention also provides, as a part of an integrated fermentation facility, a novel process for producing a solid source of inorganic carbon by sequestering carbon released from the fermentation in an alkali solution.

  13. Borderline Personality Disorder in the perinatal period: early infant and maternal outcomes.

    PubMed

    Blankley, Gaynor; Galbally, Megan; Snellen, Martien; Power, Josephine; Lewis, Andrew J

    2015-12-01

    This study examines pregnancy and early infant outcomes of pregnant women with a clinical diagnosis of Borderline Personality Disorder presenting for obstetric services to a major metropolitan maternity hospital in Victoria, Australia. A retrospective case review of pregnancy and early infant outcomes on 42 women who had been diagnosed with Borderline Personality Disorder via psychiatric assessment using DSM-IV-R criteria was undertaken. Outcomes were compared with a control group of 14,313 consisting of women and infants of non-affected women from the same hospital over the same period of time. Women presenting for obstetric services with a clinical diagnosis of Borderline Personality Disorder experienced considerable psychosocial impairment. They anticipated birth as traumatic and frequently requested early delivery. High comorbidity with substance abuse was found and high rates of referral to child protective services. Mothers with Borderline Personality Disorder were significantly more likely to have negative birth outcomes such as lowered Apgar scores, prematurity and special care nursery referral when compared with controls. These findings offer preliminary evidence to be considered by clinicians in developing treatments and services for the perinatal care of women with Borderline Personality Disorder and their infants. Further research is required in order to develop evidence informed clinical guidelines for the management of women with Borderline Personality Disorder and their infants. © The Royal Australian and New Zealand College of Psychiatrists 2015.

  14. In vitro antagonistic growth effects of Lactobacillus fermentum and lactobacillus salivarius and their fermentative broth on periodontal pathogens.

    PubMed

    Chen, Ling-Ju; Tsai, Hsiu-Ting; Chen, Wei-Jen; Hsieh, Chu-Yang; Wang, Pi-Chieh; Chen, Chung-Shih; Wang, Lina; Yang, Chi-Chiang

    2012-10-01

    As lactobacilli possess an antagonistic growth property, these bacteria may be beneficial as bioprotective agents for infection control. However, whether the antagonistic growth effects are attributed to the lactobacilli themselves or their fermentative broth remains unclear. The antagonistic growth effects of Lactobacillus salivarius and Lactobacillus fermentum as well as their fermentative broth were thus tested using both disc agar diffusion test and broth dilution method, and their effects on periodontal pathogens, including Streptococcus mutans, Streptococcus sanguis, and Porphyromonas gingivalis in vitro at different concentrations and for different time periods were also compared. Both Lactobacillus salivarius and Lactobacillus fermentum and their concentrated fermentative broth were shown to inhibit significantly the growth of Streptococcus mutans, Streptococcus sanguis, and Porphyromonas gingivalis, although different inhibitory effects were observed for different pathogens. The higher the counts of lactobacilli and the higher the folds of concentrated fermentative broth, the stronger the inhibitory effects are observed. The inhibitory effect is demonstrated to be dose-dependent. Moreover, for the lactobacilli themselves, Lactobacillus fermentum showed stronger inhibitory effects than Lactobacillus salivarius. However, the fermentative broth of Lactobacillus fermentum showed weaker inhibitory effects than that of Lactobacillus salivarius. These data suggested that lactobacilli and their fermentative broth exhibit antagonistic growth activity, and consumption of probiotics or their broth containing lactobacilli may benefit oral health.

  15. 27 CFR 24.176 - Crushing and fermentation.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Crushing and fermentation..., DEPARTMENT OF THE TREASURY LIQUORS WINE Production of Wine § 24.176 Crushing and fermentation. (a) Natural... fermentation but the density of the juice may not be reduced below 22 degrees Brix. However, if the juice is...

  16. Identification of key micro-organisms involved in Douchi fermentation by statistical analysis and their use in an experimental fermentation.

    PubMed

    Chen, C; Xiang, J Y; Hu, W; Xie, Y B; Wang, T J; Cui, J W; Xu, Y; Liu, Z; Xiang, H; Xie, Q

    2015-11-01

    To screen and identify safe micro-organisms used during Douchi fermentation, and verify the feasibility of producing high-quality Douchi using these identified micro-organisms. PCR-denaturing gradient gel electrophoresis (DGGE) and automatic amino-acid analyser were used to investigate the microbial diversity and free amino acids (FAAs) content of 10 commercial Douchi samples. The correlations between microbial communities and FAAs were analysed by statistical analysis. Ten strains with significant positive correlation were identified. Then an experiment on Douchi fermentation by identified strains was carried out, and the nutritional composition in Douchi was analysed. Results showed that FAAs and relative content of isoflavone aglycones in verification Douchi samples were generally higher than those in commercial Douchi samples. Our study indicated that fungi, yeasts, Bacillus and lactic acid bacteria were the key players in Douchi fermentation, and with identified probiotic micro-organisms participating in fermentation, a higher quality Douchi product was produced. This is the first report to analyse and confirm the key micro-organisms during Douchi fermentation by statistical analysis. This work proves fermentation micro-organisms to be the key influencing factor of Douchi quality, and demonstrates the feasibility of fermenting Douchi using identified starter micro-organisms. © 2015 The Society for Applied Microbiology.

  17. Effects of Dietary Fermented Seaweed and Seaweed Fusiforme on Growth Performance, Carcass Parameters and Immunoglobulin Concentration in Broiler Chicks

    PubMed Central

    Choi, Y. J.; Lee, S. R.; Oh, J-W.

    2014-01-01

    This study was conducted to investigate the effects of brown seaweed (Undaria pinnatifida) by-product and seaweed fusiforme (Hizikia fusiformis) by-product supplementation on growth performance and blood profiles including serum immunoglobulin (Ig) in broilers. Fermentation of seaweeds was conducted by Bacillus subtilis and Aspergillus oryzae. In a 5-wk feeding trial, 750 one-d-old broiler chicks were divided into 5 groups, and were assigned to the control diet or experimental diets including control+0.5% brown seaweed (BS) by-product, control+0.5% seaweed fusiforme (SF) by-product, control+0.5% fermented brown seaweed (FBS) by-product, and control+0.5% fermented seaweed fusiforme (FSF) by-product. As a consequence, body weight gain (BWG) and gain:feed of seaweed by-product groups were clearly higher, when compared to those of control diet group from d 18 to 35 and the entire experimental period (p<0.05). In mortality rate, seaweed by-product groups were significantly lower when compared to control diet group during entire experimental period (p<0.05). However, Feed Intake of experimental diets group was not different from that of the control group during the entire experimental period. Whereas, Feed Intake of fermented seaweed by-product groups was lower than that of non-fermented seaweed groups (p<0.05). Total organ weights, lipids, and glutamic oxalacetic transaminase (GOT) of all treatment groups were not different from those of control group. However, glutamic pyruvate transaminase (GPT) of all treatment groups was higher than that of control group at d 17 (p<0.05). In case of serum Igs concentration, the concentration of IgA antibody in BS, SF, FSF treatment groups was significantly higher than in control group at d 35 (p<0.01). IgA concentration in FBS supplementation groups was negligibly decreased when compared to the control group. IgM concentration in the serums of all treatment groups was significantly higher than in control group (p<0.05) and in

  18. A lactic acid-fermented oat gruel increases non-haem iron absorption from a phytate-rich meal in healthy women of childbearing age.

    PubMed

    Bering, Stine; Suchdev, Seema; Sjøltov, Laila; Berggren, Anna; Tetens, Inge; Bukhave, Klaus

    2006-07-01

    Lactic acid-fermented foods have been shown to increase Fe absorption in human subjects, possibly by lowering pH, activation of phytases, and formation of soluble complexes of Fe and organic acids. We tested the effect of an oat gruel fermented with Lactobacillus plantarum 299v on non-haem Fe absorption from a low-Fe bioavailability meal compared with a pasteurised, fermented oat gruel and non-fermented oat gruels. In a cross-over trial twenty-four healthy women with a mean age of 25 (sd 4) years were served (A) fermented gruel, (B) pasteurised fermented gruel, (C) pH-adjusted non-fermented gruel, and (D) non-fermented gruel with added organic acids. The meals were extrinsically labelled with 55Fe or 59Fe and consumed on 4 consecutive days, for example, in the order ABBA or BAAB followed by CDDC or DCCD in a second period. Fe absorption was determined from isotope activities in blood samples. The fermented gruel with live L. plantarum 299v increased Fe absorption significantly (P < 0.0001) compared with the pasteurised and non-fermented gruels. The lactic acid concentration in the fermented gruel was 19 % higher than in the pasteurised gruel, but the Fe absorption was increased by 50 %. In the gruel with organic acids, the lactic acid concentration was 52 % lower than in the pasteurised gruel, with no difference in Fe absorption. The fermented gruel increased non-haem Fe absorption from a phytate-rich meal in young women, indicating a specific effect of live L. plantarum 299v and not only an effect of the organic acids.

  19. Moisture content during extrusion of oats impacts the initial fermentation metabolites and probiotic bacteria during extended fermentation by human fecal microbiota.

    PubMed

    Brahma, Sandrayee; Weier, Steven A; Rose, Devin J

    2017-07-01

    Extrusion exposes flour components to high pressure and shear during processing, which may affect the dietary fiber fermentability by human fecal microbiota. The objective of this study was to determine the effect of flour moisture content during extrusion on in vitro fermentation properties of whole grain oats. Extrudates were processed at three moisture levels (15%, 18%, and 21%) at fixed screw speed (300rpm) and temperature (130°C). The extrudates were then subjected to in vitro digestion and fermentation. Extrusion moisture significantly affected water-extractable β-glucan (WE-BG) in the extrudates, with samples processed at 15% moisture (lowest) and 21% moisture (highest) having the highest concentration of WE-BG. After the first 8h of fermentation, more WE-BG remained in fermentation media in samples processed at 15% moisture compared with the other conditions. Also, extrusion moisture significantly affected the production of acetate, butyrate, and total SCFA by the microbiota during the first 8h of fermentation. Microbiota grown on extrudates processed at 18% moisture had the highest production of acetate and total SCFA, whereas bacteria grown on extrudates processed at 15% and 18% moisture had the highest butyrate production. After 24h of fermentation, samples processed at 15% moisture supported lower Bifidobacterium counts than those produced at other conditions, but had among the highest Lactobacillus counts. Thus, moisture content during extrusion significantly affects production of fermentation metabolites by the gut microbiota during the initial stages of fermentation, while also affecting probiotic bacteria counts during extended fermentation. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. Xylose fermentation to ethanol. A review

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    McMillan, J D

    1993-01-01

    The past several years have seen tremendous progress in the understanding of xylose metabolism and in the identification, characterization, and development of strains with improved xylose fermentation characteristics. A survey of the numerous microorganisms capable of directly fermenting xylose to ethanol indicates that wild-type yeast and recombinant bacteria offer the best overall performance in terms of high yield, final ethanol concentration, and volumetric productivity. The best performing bacteria, yeast, and fungi can achieve yields greater than 0.4 g/g and final ethanol concentrations approaching 5%. Productivities remain low for most yeast and particularly for fungi, but volumetric productivities exceeding 1.0 g/L-hmore » have been reported for xylose-fermenting bacteria. In terms of wild-type microorganisms, strains of the yeast Pichia stipitis show the most promise in the short term for direct high-yield fermentation of xylose without byproduct formation. Of the recombinant xylose-fermenting microorganisms developed, recombinant E. coli ATTC 11303 (pLOI297) exhibits the most favorable performance characteristics reported to date.« less

  1. Impact of initial lipid content and oxygen supply on alcoholic fermentation in champagne-like musts.

    PubMed

    Ochando, Thomas; Mouret, Jean-Roch; Humbert-Goffard, Anne; Sablayrolles, Jean-Marie; Farines, Vincent

    2017-08-01

    Available nitrogen, lipids, or oxygen are nutrients with major impact on the kinetics of winemaking fermentation. Assimilable nitrogen is usually the growth-limiting nutrient which availability determines the fermentation rate and therefore the fermentation duration. In some particular cases, as in Champagne, grape musts have high available nitrogen content and low turbidity, i.e., below 50 Nephelometric Turbidity Unit (NTU). In the case of low turbidity, the availability of lipids, particularly phytosterols, becomes limiting. In this situation, control of oxygenation, which is necessary for lipid synthesis by yeast, is particularly crucial during fermentation. To mimic and understand these situations, a synthetic medium simulating the average composition of a Champagne must was used. This medium contained phytosterol (mainly β-sitosterol) concentrations ranging from 0 to 8mg/L corresponding to turbidity between 10 and 90 NTU. Population reached during the stationary phase and the maximum fermentation rate are conditioned by the initial phytosterol concentration determining the amount of nitrogen consumption. An early loss of viability was observed when the lipid concentrations were very low. For example, the viability continuously decreased during the stationary phase to a final value of 50% for an initial phytosterol concentration of 1mg/L. In some fermentations, 10mg/L oxygen were added at the end of the growth phase to combine the effects of initial content of phytosterols in the musts and the de novo synthesis of ergosterol and unsaturated fatty acids induced by oxygen addition. Effect of oxygen supply on the fermentation kinetics was particularly significant for media with low phytosterol contents. For example, the maximum fermentation rate was increased by 1.4-fold and the fermentation time was 70h shorter with oxygen addition in the medium containing 2mg/L of phytosterols. As a consequence of the oxygen supply, for the media containing 3, 5 and 8mg/L of

  2. Fermentation and microflora of plaa-som, a thai fermented fish product prepared with different salt concentrations.

    PubMed

    Paludan-Müller, Christine; Madsen, Mette; Sophanodora, Pairat; Gram, Lone; Møller, Peter Lange

    2002-02-25

    Plaa-som is a Thai fermented fish product prepared from snakehead fish, salt, palm syrup and sometimes roasted rice. We studied the effects of different salt concentrations on decrease in pH and on microflora composition during fermentation. Two low-salt batches were prepared, containing 6% and 7% salt (w/w) as well as two high-salt batches, containing 9% and 11% salt. pH decreased rapidly from 6 to 4.5 in low-salt batches, whereas in high-salt batches, a slow or no decrease in pH was found. Lactic acid bacteria (LAB) and yeasts were isolated as the dominant microorganisms during fermentation. LAB counts increased to 10(8)-10(9) cfu g(-1) and yeast counts to 10(7)-5 x 10(7) cfu g(-1) in all batches, except in the 11% salt batch, where counts were 1-2 log lower. Phenotypic tests, ITS-PCR, carbohydrate fermentations and 16S rRNA gene sequencing identified LAB isolates as Pediococcus pentosaceus, Lactobacillus alimentarius/farciminis, Weisella confusa, L. plantarum and Lactococcus garviae. The latter species was only isolated from high-salt batches. Phenotypic characteristics, ITS-PCR and carbohydrate assimilation identified 95% of the yeasts as Zygosaccharomyces rouxii. It is concluded that the fermentation of plaa-som is delayed by a salt-level of 9% due to an inhibition of LAB growth. The growth of Z. rouxii has no influence on the fermentation rate, but may contribute positively to the flavour development of the product.

  3. Microbial diversity and their roles in the vinegar fermentation process.

    PubMed

    Li, Sha; Li, Pan; Feng, Feng; Luo, Li-Xin

    2015-06-01

    Vinegar is one of the oldest acetic acid-diluted solution products in the world. It is produced from any fermentable sugary substrate by various fermentation methods. The final vinegar products possess unique functions, which are endowed with many kinds of compounds formed in the fermentation process. The quality of vinegar is determined by many factors, especially by the raw materials and microbial diversity involved in vinegar fermentation. Given that metabolic products from the fermenting strains are directly related to the quality of the final products of vinegar, the microbial diversity and features of the dominant strains involved in different fermentation stages should be analyzed to improve the strains and stabilize fermentation. Moreover, although numerous microbiological studies have been conducted to examine the process of vinegar fermentation, knowledge about microbial diversity and their roles involved in fermentation is still fragmentary and not systematic enough. Therefore, in this review, the dominant microorganism species involved in the stages of alcoholic fermentation and acetic acid fermentation of dissimilar vinegars were summarized. We also summarized various physicochemical properties and crucial compounds in disparate types of vinegar. Furthermore, the merits and drawbacks of vital fermentation methods were generalized. Finally, we described in detail the relationships among microbial diversity, raw materials, fermentation methods, physicochemical properties, compounds, functionality, and final quality of vinegar. The integration of this information can provide us a detailed map about the microbial diversity and function involved in vinegar fermentation.

  4. Lactic acid fermentation of cassava dough into agbelima.

    PubMed

    Amoa-Awua, W K; Appoh, F E; Jakobsen, M

    1996-08-01

    The souring of cassava dough during fermentation into the fermented cassava meal, agbelima, was investigated. Four different types of traditional inocula were used to ferment the dough and increases in titrable acidity expressed as lactic acid from 0.31-0.38 to 0.78-0.91% (w/w) confirmed the fermentation to be a process of acidification. The microflora of all inocula and fermenting dough contained high counts of lactic acid bacteria, 10(8)-10(9) cfu/g in all inocula and 10(7)-10(8), 10(8)-10(9) and 10(9) cfu/g at 0, 24 and 48 h in all fermentations. Lactobacillus plantarum was the dominant species of lactic acid bacteria during all types of fermentation accounting for 51% of 171 representative isolates taken from various stages of fermentation. Other major lactic acid bacteria found were Lactobacillus brevis, 16%, Leuconostoc mesenteroides, 15% and some cocci including Streptococcus spp. whose numbers decreased with fermentation time. The lactic acid bacteria were responsible for the souring of agbelima through the production of lactic acid. All L. plantarum, L. brevis and L. mesenteroides isolates examined demonstrated linamarase as well as other enzymatic activities but did not possess tissue degrading enzymes like cellulase, pectin esterase and polygalacturonase. The aroma profile of agbelima did not vary with the type of inoculum used and in all samples the build-up of aroma compounds were dominated by a non-identified low molecular weight alcohol, 1-propanol, isoamyl alcohol, ethyl acetate, 3-methyl-1-butanol and acetoin. Substantial reductions occurred in the levels of cyanogenic compounds present in cassava during fermentation into agbelima and detoxification was enhanced by the use of inoculum.

  5. Effect of fermentation and drying on cocoa polyphenols.

    PubMed

    Albertini, Barbara; Schoubben, Aurélie; Guarnaccia, Davide; Pinelli, Filippo; Della Vecchia, Mirco; Ricci, Maurizio; Di Renzo, Gian Carlo; Blasi, Paolo

    2015-11-18

    Cocoa seed polyphenols have demonstrated interesting beneficial effects in humans. Most polyphenols contained in fresh seeds are chemically modified during fermentation, drying, and cocoa powder or chocolate production. The improvement of these procedures to obtain a high-polyphenol-content cocoa is highly desirable. To this aim, a field investigation on the effect of fermentation and natural drying on fine flavor National cocoa (cacao Nacional) was performed. Cocoa seeds were fermented for 6 days and, every day, samples were sun-dried and analyzed for polyphenol content and antioxidant power. During the first 2 days of fermentation, Folin-Ciocalteu and FRAP tests evidenced a significant reduction of polyphenol content and antioxidant capacity, respectively. Changes during the following days of fermentation were less significant. Epicatechin, the most studied member of the catechin family, followed a similar pathway of degradation. Data confirmed the high impact of fermentation and drying on cocoa seed polyphenols. Fermentation and drying are, on the one hand, necessary to obtain cocoa flavor and palatability but, on the other hand, are responsible for greatly compromising polyphenol content. To obtain high-polyphenol-content cocoa, the existing fermentation, drying, and manufacturing protocols should be scientifically reviewed to understand and modify the critical steps.

  6. Effect of bed exercises and gum chewing on abdominal sounds, flatulence and early discharge in the early period after caesarean section.

    PubMed

    Çevik, Semra Akköz; Başer, Mürüvvet

    2016-05-01

    The purpose of this study was to determine the effects of bed exercises and gum chewing on abdominal sounds, flatulence and early discharge on women who have given birth at the Cengiz Gökçek Gynecology and Obstetrics Hospital surgery services in Gaziantep city centre. Caesarean operation is the most significant surgical intervention that affects central nervous system and decelerates bowel movements in the postoperative period. Conducted studies show that practices such as gum chewing ensure that bowel functions start in a short time through early feeding and mobilisation and shorten the duration of hospital stay. A randomised controlled experimental was used. A total of 120 women participated in the study in three groups of 40 for gum, exercise and control groups. Gum was given to the groups in the gum section two hours after the ceasarean, the women chewed gum for the first eight hours until flatulence for 15 minutes every two hours. However, the women in the exercise group started moving two hours after the caesarean for the first eight hours until flatulence for five minutes every two hours. The control group consisted of women under routine treatment and care of the hospital. All women were hourly evaluated in terms of abdominal sounds, flatulence and defaecation. It was determined that following caesarean, bowel functions started in three groups at the same time, there was no significant difference between three groups. It was determined that the gum group, exercise group and the control group were discharged earlier, there was no significant difference between three groups The study results show that spinal anaesthesia have positive effects on discharge time after caesarean section operation. This study provides useful information to clinician and researchers when determining practices such as postoperative standing up in early period, gum chewing and early liquid intake related to postoperative bowel functions after abdominal operations. © 2016 John

  7. Experiments with Fungi Part 2: Fermentation.

    ERIC Educational Resources Information Center

    Dale, Michele; Hetherington, Shane

    1996-01-01

    Gives details of three experiments with alcoholic fermentation by yeasts which yield carbon dioxide and ethanol. Lists procedures for making cider, vinegar, and fermentation gases. Provides some historical background and detailed equipment requirements. (DDR)

  8. Efficacy of fermented green tea on peripheral skin temperature: a randomized and placebo-controlled clinical study.

    PubMed

    Lee, Eunyoung; Lee, Bum-Jin; Ha, Jaehyoun; Shin, Hyun-Jung; Chung, Jin-Oh

    2016-09-01

    This study was aimed at assessing the therapeutic efficacy of green tea on peripheral skin for cold hypersensitive subjects, who had the feeling of cold hands and feet at cold temperatures, one of the most common complaints in Asian women. This randomized and placebo-controlled clinical study included 60 female Korean subjects who had the feeling of cold hands and feet at cold temperatures. The subjects were randomly assigned into two groups to receive fermented green tea or a placebo (hot water). The skin temperature of the hands and feet was measured using digital infrared thermography at the baseline and at 15, 30, 45, and 60 min after the oral administration of the tea or placebo. The skin temperature of the hands and feet of the fermented green tea-administered group was significantly higher than that of the placebo-administered group. The temperature difference between the finger and the dorsum of the hand was significantly lower in the fermented green tea-administered group than that in the placebo group. Fermented green tea is helpful for cold hypersensitivity. This is the first clinical study to evaluate the efficacy of fermented green tea on peripheral skin in subjects having the feeling of cold hands and feet at cold temperatures by infrared thermography. However, further studies are necessary to evaluate the long-term effects of the fermented green tea for cold hypersensitivity and to elucidate the underlying physiological mechanism. © 2015 Wiley Periodicals, Inc.

  9. Influence of Fermentation with Different Lactic Acid Bacteria and in Vitro Digestion on the Biotransformation of Phenolic Compounds in Fermented Pomegranate Juices.

    PubMed

    Valero-Cases, Estefanía; Nuncio-Jáuregui, Nallely; Frutos, María José

    2017-08-09

    This study describes the effect of fermentation and the impact of simulated gastrointestinal digestion (SGD) of four fermented pomegranate juices with different lactic acid bacteria (LAB) on the biotransformation of phenolic compounds. The changes of the antioxidant capacity (AOC) and of LAB growth and survival in different fermented juices were also studied. Two new phenolic derivatives (catechin and α-punicalagin) were identified only in fermented juices. During SGD, the AOC increased together with the phenolic derivatives concentration mainly in the juices fermented with Lactobacillus. These derivatives were formed due to the LAB metabolism of the ellagitannins, epicatechin, and catechin after fermentation and during SGD. The FRAP assay performance might be associated with the degradation and biotransformation of catechin. The fermented pomegranate juices with these LAB increased the bioaccessibility of phenolic compounds, ensuring the survival of LAB after SGD, suggesting a possible prebiotic effect of phenolic compounds on LAB.

  10. Yeast Diversity and Persistence in Botrytis-Affected Wine Fermentations

    PubMed Central

    Mills, David A.; Johannsen, Eric A.; Cocolin, Luca

    2002-01-01

    Culture-dependent and -independent methods were used to examine the yeast diversity present in botrytis-affected (“botrytized”) wine fermentations carried out at high (∼30°C) and ambient (∼20°C) temperatures. Fermentations at both temperatures possessed similar populations of Saccharomyces, Hanseniaspora, Pichia, Metschnikowia, Kluyveromyces, and Candida species. However, higher populations of non-Saccharomyces yeasts persisted in ambient-temperature fermentations, with Candida and, to a lesser extent, Kluyveromyces species remaining long after the fermentation was dominated by Saccharomyces. In general, denaturing gradient gel electrophoresis profiles of yeast ribosomal DNA or rRNA amplified from the fermentation samples correlated well with the plating data. The direct molecular methods also revealed a Hanseniaspora osmophila population not identified in the plating analysis. rRNA analysis also indicated a large population (>106 cells per ml) of a nonculturable Candida strain in the high-temperature fermentation. Monoculture analysis of the Candida isolate indicated an extreme fructophilic phenotype and correlated with an increased glucose/fructose ratio in fermentations containing higher populations of Candida. Analysis of wine fermentation microbial ecology by using both culture-dependent and -independent methods reveals the complexity of yeast interactions enriched during spontaneous fermentations. PMID:12324335

  11. Effect of Inulin on the Viability of L. plantarum during Storage and In Vitro Digestion and on Composition Parameters of Vegetable Fermented Juices.

    PubMed

    Valero-Cases, Estefanía; Frutos, María José

    2017-06-01

    The prebiotic effect of different concentrations of inulin (0, 1 and 2%) on the growth and survival of Lactobacillus plantarum (LP) CECT 220 in blended carrot and orange juices was investigated after 24 h of fermentation, during 30 days of storage at 4 °C and through the phases of gastrointestinal digestion after different storage periods. Microbiological and chemical determinations were also carried out in all juices. The lactic fermentation increased the shelf life of the fermented juices with inulin. The hygienic-sanitary quality in fermented juices was better than the control juices. During storage, the inulin improved the viability of LP and the monosaccharide concentration remained higher with respect to the juice without inulin (40% lower). At 30 days, the fermented juices with 2% inulin after in vitro digestion presented the highest survival of L. plantarum.

  12. Angiotensin I-Converting Enzyme Inhibitor Activity on Egg Albumen Fermentation

    PubMed Central

    Nahariah, N.; Legowo, A. M.; Abustam, E.; Hintono, A.

    2015-01-01

    Lactobacillus plantarum is used for fermentation of fish products, meat and milk. However, the utilization of these bacteria in egg processing has not been done. This study was designed to evaluate the potential of fermented egg albumen as a functional food that is rich in angiotensin I-converting enzyme inhibitors activity (ACE-inhibitor activity) and is antihypertensive. A completely randomized design was used in this study with six durations of fermentation (6, 12, 18, 24, 30, and 36 h) as treatments. Six hundred eggs obtained from the same chicken farm were used in the experiment as sources of egg albumen. Bacteria L. plantarum FNCC 0027 used in the fermentation was isolated from cow’s milk. The parameters measured were the total bacteria, dissolved protein, pH, total acid and the activity of ACE-inhibitors. The results showed that there were significant effects of fermentation time on the parameters tested. Total bacteria increased significantly during fermentation for 6, 12, 18, and 24 h and then decreased with the increasing time of fermentation to 30 and 36 h. Soluble protein increased significantly during fermentation to 18 h and then subsequently decreased during of fermentation to 24, 30, and 36 h. The pH value decreased markedly during fermentation. The activities of ACE-inhibitor in fermented egg albumen increased during fermentation to 18 h and then decreased with the increasing of the duration of fermentation to 24, 30, and 36 h. The egg albumen which was fermented for 18 h resulted in a functional food that was rich in ACE-inhibitor activity. PMID:25715689

  13. Effect of pH fermentation on production bioethanol from jackfruit seeds (Artocarpus heterophyllus) through separate fermentation hydrolysis method

    NASA Astrophysics Data System (ADS)

    Arif, A. R.; Natsir, H.; Rohani, H.; Karim, A.

    2018-03-01

    Bioethanol is one of the alternative energy sourced from natural products containing carbohydrates through hydrolysis and fermentation process. Jackfruit seeds is one of the feedstock that contain high carbohydrate content but less utilized. The aims of this study to determine the effect of pH hydrolysis in the process of production bioethanol from jackfruit seeds (Artocarpus heterophyllus) through separate fermentation hydrolysis (SHF) method. The hydrolysis process uses H2SO4 as a hydrolyzing agent. The fermentation process used Saccharomyces cereviceae as a fermentor with a variation of pH 2,3 4 and 5 for 70 hours. The results showed that glucose content of 75% and pH 3 was the optimum pH of fermentation with the content of bioethanol 57.94%. The fermentation stage has an important role in increasing the levels of glucose and bioethanol in linear. The content of glucose and bioethanol of jackfruit seeds showed a great potential for development as the feedstock in bioethanol production.

  14. Importance of lactic acid bacteria in Asian fermented foods

    PubMed Central

    2011-01-01

    Lactic acid bacteria play important roles in various fermented foods in Asia. Besides being the main component in kimchi and other fermented foods, they are used to preserve edible food materials through fermentation of other raw-materials such as rice wine/beer, rice cakes, and fish by producing organic acids to control putrefactive microorganisms and pathogens. These bacteria also provide a selective environment favoring fermentative microorganisms and produce desirable flavors in various fermented foods. This paper discusses the role of lactic acid bacteria in various non-dairy fermented food products in Asia and their nutritional and physiological functions in the Asian diet. PMID:21995342

  15. Selective fermentation of carbohydrate and protein fractions of Scenedesmus, and biohydrogenation of its lipid fraction for enhanced recovery of saturated fatty acids.

    PubMed

    Lai, YenJung Sean; Parameswaran, Prathap; Li, Ang; Aguinaga, Alyssa; Rittmann, Bruce E

    2016-02-01

    Biofuels derived from microalgae have promise as carbon-neutral replacements for petroleum. However, difficulty extracting microalgae-derived lipids and the co-extraction of non-lipid components add major costs that detract from the benefits of microalgae-based biofuel. Selective fermentation could alleviate these problems by managing microbial degradation so that carbohydrates and proteins are hydrolyzed and fermented, but lipids remain intact. We evaluated selective fermentation of Scenedesmus biomass in batch experiments buffered at pH 5.5, 7, or 9. Carbohydrates were fermented up to 45% within the first 6 days, protein fermentation followed after about 20 days, and lipids (measured as fatty acid methyl esters, FAME) were conserved. Fermentation of the non-lipid components generated volatile fatty acids, with acetate, butyrate, and propionate being the dominant products. Selective fermentation of Scenedesmus biomass increased the amount of extractable FAME and the ratio of FAME to crude lipids. It also led to biohydrogenation of unsaturated FAME to more desirable saturated FAME (especially to C16:0 and C18:0), and the degree of saturation was inversely related to the accumulation of hydrogen gas after fermentation. Moreover, the microbial communities after selective fermentation were enriched in bacteria from families known to perform biohydrogenation, i.e., Porphyromonadaceae and Ruminococcaceae. Thus, this study provides proof-of-concept that selective fermentation can improve the quantity and quality of lipids that can be extracted from Scenedesmus. © 2015 Wiley Periodicals, Inc.

  16. The effect of lactic acid bacteria on cocoa bean fermentation.

    PubMed

    Ho, Van Thi Thuy; Zhao, Jian; Fleet, Graham

    2015-07-16

    Cocoa beans (Theobroma cacao L.) are the raw material for chocolate production. Fermentation of cocoa pulp by microorganisms is crucial for developing chocolate flavor precursors. Yeasts conduct an alcoholic fermentation within the bean pulp that is essential for the production of good quality beans, giving typical chocolate characters. However, the roles of bacteria such as lactic acid bacteria and acetic acid bacteria in contributing to the quality of cocoa bean and chocolate are not fully understood. Using controlled laboratory fermentations, this study investigated the contribution of lactic acid bacteria to cocoa bean fermentation. Cocoa beans were fermented under conditions where the growth of lactic acid bacteria was restricted by the use of nisin and lysozyme. The resultant microbial ecology, chemistry and chocolate quality of beans from these fermentations were compared with those of indigenous (control) fermentations. The yeasts Hanseniaspora guilliermondii, Pichia kudriavzevii, Kluyveromyces marxianus and Saccharomyces cerevisiae, the lactic acid bacteria Lactobacillus plantarum, Lactobacillus pentosus and Lactobacillus fermentum and the acetic acid bacteria Acetobacter pasteurianus and Gluconobacter frateurii were the major species found in control fermentations. In fermentations with the presence of nisin and lysozyme, the same species of yeasts and acetic acid bacteria grew but the growth of lactic acid bacteria was prevented or restricted. These beans underwent characteristic alcoholic fermentation where the utilization of sugars and the production of ethanol, organic acids and volatile compounds in the bean pulp and nibs were similar for beans fermented in the presence of lactic acid bacteria. Lactic acid was produced during both fermentations but more so when lactic acid bacteria grew. Beans fermented in the presence or absence of lactic acid bacteria were fully fermented, had similar shell weights and gave acceptable chocolates with no differences

  17. Potential Therapeutic Benefits of Green and Fermented Rooibos (Aspalathus linearis) in Dermal Wound Healing.

    PubMed

    Pringle, Nadine A; Koekemoer, Trevor C; Holzer, Andrea; Young, Carly; Venables, Luanne; van de Venter, Maryna

    2018-02-28

    The process of wound healing constitutes an ordered sequence of events that provides numerous opportunities for therapeutic intervention to improve wound repair. Rooibos, Aspalathus linearis , is a popular ingredient in skin care products, however, little scientific data exists exploring its therapeutic potential. In the present study, we evaluated the effects of fermented and aspalathin-enriched green rooibos in various in vitro models representative of dermal wound healing. Treatment of RAW 264.7 macrophages with fermented rooibos resulted in increased nitric oxide production as well as increased levels of cellular inducible nitric oxide synthase and cyclooxygenase-2, which are typical markers for classically activated macrophages. In contrast, the green extract was devoid of such activity. Using glycated gelatin as a model to mimic diabetic wounds, only the green extract showed potential to reduce cyclooxygenase-2 levels. Considering the role of reactive oxygen species in wound healing, the effects of rooibos on oxidative stress and cell death in human dermal fibroblasts was evaluated. Both fermented and green rooibos decreased cellular reactive oxygen species and attenuated apoptotic/necrotic cell death. Our findings highlight several properties that support the therapeutic potential of rooibos, and demonstrate that green and fermented rooibos present distinctly different properties with regards to their application in wound healing. The proinflammatory nature of fermented rooibos may have therapeutic value for wounds characterised with a delayed initial inflammatory phase, such as early diabetic wounds. The green extract is more suited to wounds burdened with excessive inflammation as it attenuated cyclooxygenase-2 levels and effectively protected fibroblasts against oxidative stress. Georg Thieme Verlag KG Stuttgart · New York.

  18. Tetrapod trackways from the early Middle Devonian period of Poland.

    PubMed

    Niedźwiedzki, Grzegorz; Szrek, Piotr; Narkiewicz, Katarzyna; Narkiewicz, Marek; Ahlberg, Per E

    2010-01-07

    The fossil record of the earliest tetrapods (vertebrates with limbs rather than paired fins) consists of body fossils and trackways. The earliest body fossils of tetrapods date to the Late Devonian period (late Frasnian stage) and are preceded by transitional elpistostegids such as Panderichthys and Tiktaalik that still have paired fins. Claims of tetrapod trackways predating these body fossils have remained controversial with regard to both age and the identity of the track makers. Here we present well-preserved and securely dated tetrapod tracks from Polish marine tidal flat sediments of early Middle Devonian (Eifelian stage) age that are approximately 18 million years older than the earliest tetrapod body fossils and 10 million years earlier than the oldest elpistostegids. They force a radical reassessment of the timing, ecology and environmental setting of the fish-tetrapod transition, as well as the completeness of the body fossil record.

  19. Highly viscous guar gum shifts dietary amino acids from metabolic use to fermentation substrate in domestic cats.

    PubMed

    Rochus, Kristel; Janssens, Geert P J; Van de Velde, Hannelore; Verbrugghe, Adronie; Wuyts, Birgitte; Vanhaecke, Lynn; Hesta, Myriam

    2013-03-28

    The present study evaluated the potential of affecting amino acid metabolism through intestinal fermentation in domestic cats, using dietary guar gum as a model. Apparent protein digestibility, plasma fermentation metabolites, faecal fermentation end products and fermentation kinetics (exhaled breath hydrogen concentrations) were evaluated. Ten cats were randomly assigned to either guar gum- or cellulose-supplemented diets, that were fed in two periods of 5 weeks in a crossover design. No treatment effect was seen on fermentation kinetics. The apparent protein digestibility (P= 0.07) tended to be lower in guar gum-supplemented cats. As a consequence of impaired small-intestinal protein digestion and amino acid absorption, fermentation of these molecules in the large intestine was stimulated. Amino acid fermentation has been shown to produce high concentrations of acetic and butyric acids. Therefore, no treatment effect on faecal propionic acid or plasma propionylcarnitine was observed in the present study. The ratio of faecal butyric acid:total SCFA tended to be higher in guar gum-supplemented cats (P= 0.05). The majority of large-intestinal butyric acid is absorbed by colonocytes and metabolised to 3-hydroxy-butyrylcoenzyme A, which is then absorbed into the bloodstream. This metabolite was analysed in plasma as 3-hydroxy-butyrylcarnitine, which was higher (P= 0.02) in guar gum-supplemented cats. In all probability, the high viscosity of the guar gum supplement was responsible for the impaired protein digestion and amino acid absorption. Further research is warranted to investigate whether partially hydrolysed guar gum is useful to potentiate the desirable in vivo effects of this fibre supplement.

  20. Fermentation of wheat: effects of backslopping different proportions of pre-fermented wheat on the microbial and chemical composition.

    PubMed

    Moran, Colm A; Scholten, Ronald H J; Tricarico, Juan M; Brooks, Peter H; Verstegen, Martin W A

    2006-04-01

    The objective of the study was to examine effect of backslop on the chemical and microbiological characteristics of fermented wheat (FW). Coarsely ground wheat was mixed with water (1:3 wt/wt) and inoculated with 6 log cfu ml(-1) each of an overnight culture of Lactobacillus plantarum and Pediococcus pentosaceus. Four fermentation treatments were conducted in 45 1, closed, PVC containers over 48 hours. Three treatments investigated the benefits of the addition of previously fermented wheat (backslopping, BSL) at different proportions (0.20, 0.33 or 0.42 kg) to freshly prepared wheat. The control treatment contained no addition of BSL. Elimination of coliforms from the FW within 48 h was only achieved through backslopping; where coliform bacteria counts decreased from approximately 6.5 log10 cfu ml(-1) to less than 3 log10 cfu ml(-1). There was no apparent advantage in increasing the backslop proportion above 0.20. However, the exclusion of coliform bacteria required the pH to remain below 4.0 for at a minimum of 24 h. The results of these studies indicate that fermentation of wheat has the potential to reduce the risk of feed-borne colibacillosis and provides a practical alternative to producers that cannot ferment multiple diets or have limited fermentation capacity.

  1. Real-Time Monitoring of Chemical Changes in Three Kinds of Fermented Milk Products during Fermentation Using Quantitative Difference Nuclear Magnetic Resonance Spectroscopy.

    PubMed

    Lu, Yi; Ishikawa, Hiroto; Kwon, Yeondae; Hu, Fangyu; Miyakawa, Takuya; Tanokura, Masaru

    2018-02-14

    Fermented milk products are rising in popularity throughout the world as a result of their health benefits, including improving digestion, normalizing the function of the immune system, and aiding in weight management. This study applies an in situ quantitative nuclear magnetic resonance method to monitor chemical changes in three kinds of fermented milk products, Bulgarian yogurt, Caspian Sea yogurt, and kefir, during fermentation. As a result, the concentration changes in nine organic compounds, α/β-lactose, α/β-galactose, lactic acid, citrate, ethanol, lecithin, and creatine, were monitored in real time. This revealed three distinct metabolic processes in the three fermented milk products. Moreover, pH changes were also determined by variations in the chemical shift of citric acid during the fermentation processes. These results can be applied to estimate microbial metabolism in various flora and help guide the fermentation and storage of various fermented milk products to improve their quality, which may directly influence human health.

  2. Koji--where East meets West in fermentation.

    PubMed

    Zhu, Yang; Tramper, Johannes

    2013-12-01

    Almost all biotechnological processes originate from traditional food fermentations, i.e. the many indigenous processes that can be found already in the written history of thousands of years ago. We still consume many of these fermented foods and beverages on a daily basis today. The evolution of these traditional processes, in particular since the 19th century, stimulated and influenced the development of modern biotechnological processes. In return, the development of modern biotechnology and related advanced techniques will no doubt improve the process, the product quality and the safety of our favourite fermented foods and beverages. In this article, we describe the relationship between these traditional food fermentations and modern biotechnology. Using Koji and its derived product soy sauce as examples, we address the mutual influences that will provide us with a better future concerning the quality, safety and nutritional effect of many fermented food products. © 2013.

  3. Acetic acid bacteria in fermented foods and beverages.

    PubMed

    De Roos, Jonas; De Vuyst, Luc

    2018-02-01

    Although acetic acid bacteria (AAB) are commonly found in spontaneous or backslopped fermented foods and beverages, rather limited knowledge about their occurrence and functional role in natural food fermentation ecosystems is available. Not only is their cultivation, isolation, and identification difficult, their cells are often present in a viable but not culturable state. Yet, they are promising starter cultures either to better control known food fermentation processes or to produce novel fermented foods and beverages. This review summarizes the most recent findings on the occurrence and functional role of AAB in natural food fermentation processes such as lambic beer, water kefir, kombucha, and cocoa. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. Effects of concentrate replacement by feed blocks on ruminal fermentation and microbial growth in goats and single-flow continuous-culture fermenters.

    PubMed

    Molina-Alcaide, E; Pascual, M R; Cantalapiedra-Hijar, G; Morales-García, E Y; Martín-García, A I

    2009-04-01

    The effect of replacing concentrate with 2 different feed blocks (FB) on ruminal fermentation and microbial growth was evaluated in goats and in single-flow continuous-culture fermenters. Diets consisted of alfalfa hay plus concentrate and alfalfa hay plus concentrate with 1 of the 2 studied FB. Three trials were carried out with 6 rumen-fistulated Granadina goats and 3 incubation runs in 6 single-flow continuous-culture fermenters. Experimental treatments were assigned randomly within each run, with 2 repetitions for each diet. At the end of each in vivo trial, the rumen contents were obtained for inoculating the fermenters. For each incubation run, the fermenters were inoculated with ruminal fluid from goats fed the same diet supplied to the corresponding fermenter flask. The average pH values, total and individual VFA, and NH(3)-N concentrations, and acetate:propionate ratios in the rumen of goats were not affected (P >or= 0.10) by diet, whereas the microbial N flow (MNF) and efficiency were affected (P fermenters, the diet affected pH (P<0.001), propionate concentrations (P=0.01), acetate:propionate ratio (P=0.03), carbohydrate digestibility (P >or= 0.05), and total (P=0.02), NH(3) (P=0.005), and non-NH(3) (P=0.02) N flows, whereas the efficiency of VFA production was not affected (P=0.75). The effect of diet on MNF and efficiency depended on the bacterial pellet used as a reference. An effect (P<0.05) of diet on the composition of solid- and liquid-associated bacteria was observed. The compositions of liquid-associated bacteria in the fermenter contents and effluent were similar (P=0.05). Differences (P<0.001) between in vivo and in vitro values for most fermentation variables and bacterial pellet compositions were found. Partial replacement of the concentrate with FB did not greatly compromise carbohydrate fermentation in unproductive goats. However, this was not the case for MNF and

  5. Understanding Kombucha Tea Fermentation: A Review.

    PubMed

    Villarreal-Soto, Silvia Alejandra; Beaufort, Sandra; Bouajila, Jalloul; Souchard, Jean-Pierre; Taillandier, Patricia

    2018-03-01

    Kombucha is a beverage of probable Manchurian origins obtained from fermented tea by a microbial consortium composed of several bacteria and yeasts. This mixed consortium forms a powerful symbiosis capable of inhibiting the growth of potentially contaminating bacteria. The fermentation process also leads to the formation of a polymeric cellulose pellicle due to the activity of certain strains of Acetobacter sp. The tea fermentation process by the microbial consortium was able to show an increase in certain biological activities which have been already studied; however, little information is available on the characterization of its active components and their evolution during fermentation. Studies have also reported that the use of infusions from other plants may be a promising alternative. Kombucha is a traditional fermented tea whose consumption has increased in the recent years due to its multiple functional properties such as anti-inflammatory potential and antioxidant activity. The microbiological composition of this beverage is quite complex and still more research is needed in order to fully understand its behavior. This study comprises the chemical and microbiological composition of the tea and the main factors that may affect its production. © 2018 Institute of Food Technologists®.

  6. Yeast Biodiversity from DOQ Priorat Uninoculated Fermentations.

    PubMed

    Padilla, Beatriz; García-Fernández, David; González, Beatriz; Izidoro, Iara; Esteve-Zarzoso, Braulio; Beltran, Gemma; Mas, Albert

    2016-01-01

    Climate, soil, and grape varieties are the primary characteristics of terroir and lead to the definition of various appellations of origin. However, the microbiota associated with grapes are also affected by these conditions and can leave a footprint in a wine that will be part of the characteristics of terroir. Thus, a description of the yeast microbiota within a vineyard is of interest not only to provide a better understanding of the winemaking process, but also to understand the source of microorganisms that maintain a microbial footprint in wine from the examined vineyard. In this study, two typical grape varieties, Grenache and Carignan, have been sampled from four different vineyards in the DOQ Priorat winegrowing region. Afterward, eight spontaneous alcoholic fermentations containing only grapes from one sampling point and of one variety were conducted at laboratory scale. The fermentation kinetics and yeast population dynamics within each fermentation experiment were evaluated. Yeast identification was performed by RFLP-PCR of the 5.8S-ITS region and by sequencing D1/D2 of the 26S rRNA gene of the isolates. The fermentation kinetics did not indicate clear differences between the two varieties of grapes or among vineyards. Approximately 1,400 isolates were identified, exhibiting high species richness in some fermentations. Of all the isolates studied, approximately 60% belong to the genus Hanseniaspora, 16% to Saccharomyces, and 11% to Candida. Other minor genera, such as Hansenula, Issatchenkia, Kluyveromyces, Saccharomycodes, and Zygosaccharomyces, were also found. The distribution of the identified yeast throughout the fermentation process was studied, and Saccharomyces cerevisiae was found to be present mainly at the end of the fermentation process, while Aureobasidium pullulans was isolated primarily during the first days of fermentation in three of the eight spontaneous fermentations. This work highlights the complexity and diversity of the vineyard

  7. Yeast Biodiversity from DOQ Priorat Uninoculated Fermentations

    PubMed Central

    Padilla, Beatriz; García-Fernández, David; González, Beatriz; Izidoro, Iara; Esteve-Zarzoso, Braulio; Beltran, Gemma; Mas, Albert

    2016-01-01

    Climate, soil, and grape varieties are the primary characteristics of terroir and lead to the definition of various appellations of origin. However, the microbiota associated with grapes are also affected by these conditions and can leave a footprint in a wine that will be part of the characteristics of terroir. Thus, a description of the yeast microbiota within a vineyard is of interest not only to provide a better understanding of the winemaking process, but also to understand the source of microorganisms that maintain a microbial footprint in wine from the examined vineyard. In this study, two typical grape varieties, Grenache and Carignan, have been sampled from four different vineyards in the DOQ Priorat winegrowing region. Afterward, eight spontaneous alcoholic fermentations containing only grapes from one sampling point and of one variety were conducted at laboratory scale. The fermentation kinetics and yeast population dynamics within each fermentation experiment were evaluated. Yeast identification was performed by RFLP-PCR of the 5.8S-ITS region and by sequencing D1/D2 of the 26S rRNA gene of the isolates. The fermentation kinetics did not indicate clear differences between the two varieties of grapes or among vineyards. Approximately 1,400 isolates were identified, exhibiting high species richness in some fermentations. Of all the isolates studied, approximately 60% belong to the genus Hanseniaspora, 16% to Saccharomyces, and 11% to Candida. Other minor genera, such as Hansenula, Issatchenkia, Kluyveromyces, Saccharomycodes, and Zygosaccharomyces, were also found. The distribution of the identified yeast throughout the fermentation process was studied, and Saccharomyces cerevisiae was found to be present mainly at the end of the fermentation process, while Aureobasidium pullulans was isolated primarily during the first days of fermentation in three of the eight spontaneous fermentations. This work highlights the complexity and diversity of the vineyard

  8. Brettanomyces as a starter culture in rice-steamed sponge cake: a traditional fermented food in China.

    PubMed

    Wu, Peng; Xu, Xiaoyun; Xu, Yongxia; Chen, Qingchan; Pan, Siyi

    2011-11-01

    The potential use of Brettanomyces anomalus PSY-001 as an additional starter culture for the production of Rice-steamed sponge cake (RSSC), a traditional fermented food in China, was investigated. Two productions of RSSC, each containing batches of experimental cakes with Brettanomyces added and reference cakes with the leavened liquid added were carried out. For both experimental and reference cakes, chemical analysis and sensory evaluation were carried out during the fermentation period. The results showed that experimental cakes had desirable aroma and taste. The observed differences indicate a positive contribution to the overall quality of RSSC by B. anomalus PSY-001.

  9. Fermentation process improvement of a Chinese traditional food: soybean residue cake.

    PubMed

    Yao, Yingzheng; Pan, Siyi; Wang, Kexing; Xu, Xiaoyun

    2010-09-01

    Fermentation process improvement of soybean residue cake, a Chinese traditional fermented food, and its physicochemical analysis during fermentation were studied. One of the dominant strains in the fermentation was isolated and identified as Mucor racemosus Fresenius. The fermentation process was improved by subsection fermentation. The crude protein content decreased from 19.95 ± 0.03% in the raw soybean residue to 16.85 ± 0.10% in the fermented products, and the formaldehyde nitrogen content increased from 0.068 ± 0.004% to 0.461 ± 0.022% in final fermented cakes. Hardness of samples significantly (P < 0.05) increased whereas springiness, cohesiveness, and resilience significantly (P < 0.05) decreased with increasing fermentation time, respectively. Microstructure observations showed obvious change of the surface of cake samples during the fermentation process. During the soybean processing, it will produce plenty of by-products, and the most part of them is soybean residue. The discarded soybean residue causes economic loss. Fortunately, we can obtain nutritious and delicious fermented soybean residue cakes by fermenting soybean residue as raw material.

  10. Drying performance of fermented cassava (fercaf) using a convective multiple flash dryer

    NASA Astrophysics Data System (ADS)

    Handojo, Lienda A.; Zefanya, Samuel; Christanto, Yohanes

    2017-05-01

    Fermented cassava (fercaf) is a tropical versatile carbohydrate source flour which is produced by modifying the characteristics of cassava. Drying process is one of the processes that could influence the quality of fercaf. In general, for food application, convective and vacuum drying were used, however recently another advanced method using combination of both convective and vacuum, i.e. convective multiple flash drying (CMFD), was proposed. This method is conducted by repeating cycles of convective and vacuum drying in intermittent manner. Cassava chips with thickness of 0.1-0.2 cm were fermented for 24 hours at room condition. Then, the drying process was conducted by using 3 techniques, i.e. convective, vacuum, and combined method (CMFD), with operation temperatures between 50 and 70°C for 10 hours or until fermented cassava reached a moisture content of less than 20%. The study shows that CMFD was the fastest drying method with only 5-6 hours period compared to 8-10 hours using vacuum and more than 10 hours using convective method. CMFD also produces harder fercaf chips than those of vacuum and convective methods. Moreover, this research also proves that the operating pressure and temperature influence the moisture content.

  11. Nitrogen availability of grape juice limits killer yeast growth and fermentation activity during mixed-culture fermentation with sensitive commercial yeast strains.

    PubMed Central

    Medina, K; Carrau, F M; Gioia, O; Bracesco, N

    1997-01-01

    The competition between selected or commercial killer strains of type K2 and sensitive commercial strains of Saccharomyces cerevisiae was studied under various conditions in sterile grape juice fermentations. The focus of this study was the effect of yeast inoculation levels and the role of assimilable nitrogen nutrition on killer activity. A study of the consumption of free amino nitrogen (FAN) by pure and mixed cultures of killer and sensitive cells showed no differences between the profiles of nitrogen assimilation in all cases, and FAN was practically depleted in the first 2 days of fermentation. The effect of the addition of assimilable nitrogen and the size of inoculum was examined in mixed killer and sensitive strain competitions. Stuck and sluggish wine fermentations were observed to depend on nitrogen availability when the ratio of killer to sensitive cells was low (1:10 to 1:100). A relationship between the initial assimilable nitrogen content of must and the proportion of killer cells during fermentation was shown. An indirect relationship was found between inoculum size and the percentage of killer cells: a smaller inoculum resulted in a higher proportion of killer cells in grape juice fermentations. In all cases, wines obtained with pure-culture fermentations were preferred to mixed-culture fermentations by sensory analysis. The reasons why killer cells do not finish fermentation under competitive conditions with sensitive cells are discussed. PMID:9212430

  12. Ethanol fermentation characteristics of recycled water by Saccharomyces cerevisiae in an integrated ethanol-methane fermentation process.

    PubMed

    Yang, Xinchao; Wang, Ke; Wang, Huijun; Zhang, Jianhua; Mao, Zhonggui

    2016-11-01

    An process of integrated ethanol-methane fermentation with improved economics has been studied extensively in recent years, where the process water used for a subsequent fermentation of carbohydrate biomass is recycled. This paper presents a systematic study of the ethanol fermentation characteristics of recycled process water. Compared with tap water, fermentation time was shortened by 40% when mixed water was employed. However, while the maximal ethanol production rate increased from 1.07g/L/h to 2.01g/L/h, ethanol production was not enhanced. Cell number rose from 0.6×10(8) per mL in tap water to 1.6×10(8) per mL in mixed water but although biomass increased, cell morphology was not affected. Furthermore, the use of mixed water increased the glycerol yield but decreased that of acetic acid, and the final pH with mixed water was higher than when using tap water. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. Accelerated Fermentation of Brewer's Wort by Saccharomyces carlsbergensis1

    PubMed Central

    Porter, Sookie C.

    1975-01-01

    A rapid procedure for wort fermentation with Saccharomyces carlsbergensis at 12 C is described. Fermentation time was reduced from 7 to 4 days with normal inoculum by shaking. Increasing the inoculation to 5 to 10 times normal and shaking resulted in complete fermentation in 3 days. Maximum yeast population was reached rapidly with the large inocula, but fermentation proceeded at approximately the same rate when inoculations in excess of four times the normal were used. Similar results were obtained with both small-scale (100 ml) and microbrew (2.4 liters) fermentations. PMID:16350046

  14. Simultaneous saccharification and fermentation (SSF) using cellobiose fermenting yeast Brettanomyces custersii (CBS 5512)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Spindler, D.D.; Grohmann, K.; Wyman, C.E.

    1991-01-16

    A process for producing ethanol from plant biomass includes forming a substrate from the biomass with the substrate including hydrolysates of cellulose and hemicellulose. A species of the yeast Brettanomyces custersii (CBS 5512), which has the ability to ferment both cellobiose and glucose to ethanol, is then selected and isolated. The substrate is inoculated with this yeast, and the inoculated substrate is then fermented under conditions favorable for cell viability and conversion of hydrolysates to ethanol.

  15. Production of Fermented Kale Juices with Lactobacillus Strains and Nutritional Composition

    PubMed Central

    Kim, Seong Yeong

    2017-01-01

    Fermented kale juices using four types of lactobacilli were produced in the present study. After 48 h of fermentation time, viable cell counts of all ferments reached an above 109 CFU/mL. The viability of the ferments after cold storage in the refrigerator for 4 weeks showed 108 CFU/mL in all ferments. Among four types of fermented kale juices, the ferment of Lactobacillus acidophilus IFO 3025 indicated a good nutritional composition, including neutral sugar (1,909.76 μg/mL), reducing sugar (564.00 μg/mL, P<0.05), and protein contents (160.06 μg/mL, P<0.05). The results of mineral composition analysis had the highest potassium value in all ferments (854.16~895.07 μg/mL), particularly in the ferment of Lactobacillus brevis FSB-1 (P<0.001), which is necessary to sustain osmotic pressure, prevention of high blood pressure, and protein synthesis. Moreover, calcium, phosphorus, and magnesium contents related to bone health were generally sufficient in all ferments. Consequently, in this study, fermented kale juices may be suggested as a healthy fermented beverage with essential nutrients. However, the acceptability of the fermented kale juice to the Korean taste should be further investigated with a trained taste panel to determine whether inoculated fermentation could be an option for the consumers. PMID:29043222

  16. Low Fermentation pH Is a Trigger to Alcohol Production, but a Killer to Chain Elongation.

    PubMed

    Ganigué, Ramon; Sánchez-Paredes, Patricia; Bañeras, Lluis; Colprim, Jesús

    2016-01-01

    Gasification of organic wastes coupled to syngas fermentation allows the recovery of carbon in the form of commodity chemicals, such as carboxylates and biofuels. Acetogenic bacteria ferment syngas to mainly two-carbon compounds, although a few strains can also synthesize four-, and six-carbon molecules. In general, longer carbon chain products have a higher biotechnological (and commercial) value due to their higher energy content and their lower water solubility. However, de-novo synthesis of medium-chain products from syngas is quite uncommon in acetogenic bacteria. An alternative to de-novo synthesis is bioproduction of short-chain products (C2 and C4), and their subsequent elongation to C4, C6, or C8 through reversed β-oxidation metabolism. This two-step synergistic approach has been successfully applied for the production of up to C8 compounds, although the accumulation of alcohols in these mixed cultures remained below detection limits. The present work investigates the production of higher alcohols from syngas by open mixed cultures (OMC). A syngas-fermenting community was enriched from sludge of an anaerobic digester for a period of 109 days in a lab-scale reactor. At the end of this period, stable production of ethanol and butanol was obtained. C6 compounds were only transiently produced at the beginning of the enrichment phase, during which Clostridium kluyveri, a bacterium able to carry out carbon chain elongation, was detected in the community. Further experiments showed pH as a critical parameter to maintain chain elongation activity in the co-culture. Production of C6 compounds was recovered by preventing fermentation pH to decrease below pH 4.5-5. Finally, experiments showed maximal production of C6 compounds (0.8 g/L) and alcohols (1.7 g/L of ethanol, 1.1 g/L of butanol, and 0.6 g/L of hexanol) at pH 4.8. In conclusion, low fermentation pH is critical for the production of alcohols, although detrimental to C. kluyveri. Fine control of fermentation

  17. Sterilization of fermentation vessels by ethanol/water mixtures

    DOEpatents

    Wyman, Charles E.

    1999-02-09

    A method for sterilizing process fermentation vessels with a concentrated alcohol and water mixture integrated in a fuel alcohol or other alcohol production facility. Hot, concentrated alcohol is drawn from a distillation or other purification stage and sprayed into the empty fermentation vessels. This sterilizing alcohol/water mixture should be of a sufficient concentration, preferably higher than 12% alcohol by volume, to be toxic to undesirable microorganisms. Following sterilization, this sterilizing alcohol/water mixture can be recovered back into the same distillation or other purification stage from which it was withdrawn. The process of this invention has its best application in, but is not limited to, batch fermentation processes, wherein the fermentation vessels must be emptied, cleaned, and sterilized following completion of each batch fermentation process.

  18. Quantitative Profiling of Ester Compounds Using HS-SPME-GC-MS and Chemometrics for Assessing Volatile Markers of the Second Fermentation in Bottle.

    PubMed

    Muñoz-Redondo, José Manuel; Cuevas, Francisco Julián; León, Juan Manuel; Ramírez, Pilar; Moreno-Rojas, José Manuel; Ruiz-Moreno, María José

    2017-04-05

    A quantitative approach using HS-SPME-GC-MS was performed to investigate the ester changes related to the second fermentation in bottle. The contribution of the type of base wine to the final wine style is detailed. Furthermore, a discriminant model was developed based on ester changes according to the second fermentation (with 100% sensitivity and specificity values). The application of a double-check criteria according to univariate and multivariate analyses allowed the identification of potential volatile markers related to the second fermentation. Some of them presented a synthesis-ratio around 3-fold higher after this period and they are known to play a key role in wine aroma. Up to date, this is the first study reporting the role of esters as markers of the second fermentation. The methodology described in this study confirmed its suitability for the wine aroma field. The results contribute to enhance our understanding of this fermentative step.

  19. [Angiopoietins predict long-term outcomes after aneurysmal subarachnoid hemorrhage during an early period].

    PubMed

    Wang, Yi; Wang, Dong; Wei, Huijie; Tian, Ye; Jiang, Rongcai; Yue, Shuyuan; Zhang, Jianning

    2015-05-19

    To evaluate the association between serum levels of angiopoietins (Ang) during an early period (within 72 h) and clinical outcomes after aneurysmal subarachnoid haemorrhage (aSAH). This prospective study was conducted at Department of Neurosurgery, Tianjin Medical University General Hospital. Blood samples from 37 aSAH patients were collected at 8 h (or < 8 h), 24 h, 72 h after an onset of SAH. The serum levels of Ang-1, Ang-2 and Tie-2 were measured by enzyme-linked immunosorbent assay (ELISA). They were followed up for 3 months by Glasgow outcome score extended (GOSE). Those with GOSE > 5 were counted as a good outcome while those with GOSE ≤ 5 had a poor outcome. A total of 37 patients with aSAH and 39 healthy controls (HC) were enrolled. The aSAH patients showed a significant rise of Ang-1 within 8 h as compared with HC. The outcomes were good (n = 15) and poor (n = 22). Serum Ang-1 at 8 h (or < 8 h), 24 h and 72 h in good outcomers showed significantly higher than that in poor outcomers [(52 ± 24) vs (37 ± 17) mg/L, (62 ± 26) vs (45 ± 17) mg/L, (107 ± 27) vs (72 ± 18) mg/L]. The serum level of Ang-1 at 8 h and 24 h was one of independent risk factors for aSAH patients by multiariable Logistic regression analysis [adjected OR (95% CI) 1.095 (1.015-1.181) and 1.109 (1.016-1.211)] (P < 0.05). High serum level of Ang-1 during an early period (within 72 h) was associated with good outcomers (r = 0.627, P < 0.001). The serum levels of angiopoietins are significantly altered in aSAH patients, especially higher in good outcomers. And abnormal levels of angiopoietins may affect early brain injury (EBI) after SAH, structural integrity and recovery of blood-brain barrier (BBB) and long-term outcomes in aSAH patients.

  20. The use of fermentation liquid of wastewater primary sedimentation sludge as supplemental carbon source for denitrification based on enhanced anaerobic fermentation.

    PubMed

    Liu, Feng; Tian, Yu; Ding, Yi; Li, Zhipeng

    2016-11-01

    Wastewater primary sedimentation sludge was prepared into fermentation liquid as denitrification carbon source, and the main components of fermentation liquid was short-chain volatile fatty acids. Meanwhile, the acetic acid and propionic acid respectively accounted for about 29.36% and 26.56% in short-chain volatile fatty acids. The performance of fermentation liquid, methanol, acetic acid, propionic acid and glucose used as sole carbon source were compared. It was found that the denitrification rate with fermentation liquid as carbon source was 0.17mgNO3(-)-N/mg mixed liquor suspended solid d, faster than that with methanol, acetic acid, and propionic acid as sole carbon source, and lower than that with glucose as sole carbon source. For the fermentation liquid as carbon source, the transient accumulation of nitrite was insignificantly under different initial total nitrogen concentration. Therefore, the use of fermentation liquid for nitrogen removal could improve denitrification rate, and reduce nitrite accumulation in denitrification process. Copyright © 2016 Elsevier Ltd. All rights reserved.

  1. Butanol production by fermentation: efficient bioreactors

    USDA-ARS?s Scientific Manuscript database

    Energy security, environmental concerns, and business opportunities in the emerging bio-economy have generated strong interest in the production of n-butanol by fermentation. Acetone butanol ethanol (ABE or solvent) batch fermentation process is product limiting because butanol even at low concentra...

  2. Interceptive orthopedics for the correction of maxillary transverse and sagittal deficiency in the early mixed dentition period

    PubMed Central

    Talapaneni, Ashok Kumar; Kumar, Karnati Praveen; Kommi, Pradeep Babu; Nuvvula, Sivakumar

    2011-01-01

    Dentofacial Orthopedics directed to a hypoplastic maxilla in the prepubertal period redirects growth of the maxilla in the vertical, transverse and sagittal planes of space. The orthopedic correction of maxillary hypoplasia in the early mixed dentition period thus intercepts the establishment of permanent structural asymmetry in the mandible and helps in the achievement of optimal dentofacial esthetics. This paper presents the growth redirection in a hypoplastic maxilla of an 8-year-old girl with simultaneous rapid maxillary expansion and protraction headgear therapy for a period of 11 months which corrected the posterior unilateral cross-bite, the positional asymmetry of the mandible and established an orthognathic profile in the individual. PMID:22346162

  3. Evaluation of right ventricular function in early period following transcatheter closure of atrial septal defect.

    PubMed

    Ağaç, Mustafa Tarık; Akyüz, Ali Rıza; Acar, Zeydin; Akdemir, Ramazan; Korkmaz, Levent; Kırış, Abdülkadir; Erkuş, Emre; Erkan, Hakan; Celik, Sükrü

    2012-03-01

    There is limited data on alterations in novel right ventricular (RV) function indices like tricuspid annular plane systolic excursion (TAPSE) and tricuspid annular systolic velocity (TASV) after transcatheter atrial septal defect (ASD) closure. We aimed to evaluate RV function by echocardiography (ECG) with these novel indices in early period in patients with secundum-type ASD that was closed percutaneously. Patients were enrolled to study if they had secundum-type ASD that was suitable for percutaneous closure. Patient population consisted of 4 men and 16 women. Echocardiography was performed before and 1 month after closure. Mean age was 37 ± 16. Mean diameter of ASD and total atrial septum length measured by ECG were 19 ± 6 mm and 49 ± 7 mm, respectively. Mean diameter of defect in transesophageal echocardiography was 20 ± 6 mm. Stretched mean diameter in catheterization was 23 ± 6 mm. One month after closure, there were statistically significant decreases in RV end-diastolic diameters (43.3 ± 10.7 mm vs. 34.9 ± 5.5 mm; P < 0.001), RV/left ventricular (LV) end-diastolic diameter ratio (1.1 ± 0.3 vs. 0.87 ± 0.1; P < 0.001), TASV (16.9 ± 3.2 cm/sec vs. 14.3 ± 3.3 cm/sec; P < 0.05), early diastolic tricuspid annular velocity (15.3 ± 3.1 cm/sec vs. 13.4 ± 2.4 cm/sec P <0.05), late diastolic tricuspid annular velocity (16.2 ± 5.4 cm/sec vs. 14.3 ± 6.3 cm/sec; P < 0.05), and TAPSE (29.9 ± 6.2 mm vs. 22.4 ± 7.4 mm; P < 0.001). LV end-diastolic diameter (38.0 ± 6.9 mm and 40.0 ± 4.5 P < 0.05) was increased, whereas there was no change in LV ejection fraction. Closure of ASD by using Amplatzer devices led to decrease in right heart chamber size, tissue Doppler-derived tricuspid annular velocities and TAPSE in early period. © 2011, Wiley Periodicals, Inc.

  4. Anti-inflammatory effects of fermented and non-fermented Sophora flavescens: a comparative study.

    PubMed

    Han, Chun-chao; Wei, Hong; Guo, Jianyou

    2011-10-26

    The roots of Sophora flavescens (Leguminosae) have been used in East Asian countries as an herbal medicine and a food ingredient for thousands of years. The aim of the present study was to investigate the effects of S. flavescens fermentation on endotoxin-induced uveitis (EIU) in rats. EIU was induced in rats via a footpad injection of lipopolysaccharide (LPS). Immediately after the LPS inoculation, fermented and non-fermented extracts of S. flavescens (FSE and NFSE, respectively) were administered orally, and the aqueous humor was collected from both eyes 24 hours later. The anti-inflammatory effects of FSE and NFSE were examined in terms of regulation of nuclear factor kappa B (NF-κB) activation and the expression of interleukin-1β (IL-1β), tumor necrosis factor-α (TNF-α), inducible nitric oxide synthase (iNOS), intercellular cell adhesion molecule (ICAM)-1, and cyclooxygenase-2 (COX-2). The regulation of maleic dialdehyde (MDA) levels and polymorphonuclear cell (PMN) infiltration by FSE and NFSE were also examined. Treatment with FSE significantly inhibited LPS-induced increases in IL-1β and TNF-α production and the expression of iNOS, ICAM-1 and COX-2. Moreover, FSE suppressed LPS-induced NF-κB activation, and reduced both MDA levels and infiltration by PMN. These results indicate that solid state fermentation may enhance the anti-inflammatory effects of S. flavescens.

  5. Estimation of abbreviated mycophenolic acid area under the concentration-time curve during early posttransplant period by limited sampling strategy.

    PubMed

    Mohammadpour, A-H; Nazemian, F; Abtahi, B; Naghibi, M; Gholami, K; Rezaee, S; Nazari, M-R A; Rajabi, O

    2008-12-01

    Area under the concentration curve (AUC) of mycophenolic acid (MPA) could help to optimize therapeutic drug monitoring during the early post-renal transplant period. The aim of this study was to develop a limited sampling strategy to estimate an abbreviated MPA AUC within the first month after renal transplantation. In this study we selected 19 patients in the early posttransplant period with normal renal graft function (glomerular filtration rate > 70 mL/min). Plasma MPA concentrations were measured using reverse-phase high-performance liquid chromatography. MPA AUC(0-12h) was calculated using the linear trapezoidal rule. Multiple stepwise regression analysis was used to determine the minimal and convenient time points of MPA levels that could be used to derive model equations best fitted to MPA AUC(0-12h). The regression equation for AUC estimation that gave the best performance was AUC = 14.46 C(10) + 15.547 (r(2) = .882). The validation of the method was performed using the jackknife method. Mean prediction error of this model was not different from zero (P > .05) and had a high root mean square prediction error (8.06). In conclusion, this limited sampling strategy provided an effective approach for therapeutic drug monitoring during the early posttransplant period.

  6. A review on the fermentation of foods and the residues of pesticides-biotransformation of pesticides and effects on fermentation and food quality.

    PubMed

    Regueiro, Jorge; López-Fernández, Olalla; Rial-Otero, Raquel; Cancho-Grande, Beatriz; Simal-Gándara, Jesús

    2015-01-01

    Residues of pesticides in food are influenced by processing such as fermentation. Reviewing the extensive literature showed that in most cases, this step leads to large reductions in original residue levels in the fermented food, with the formation of new pesticide by-products. The behavior of residues in fermentation can be rationalized in terms of the physical-chemical properties of the pesticide and the nature of the process. In addition, the presence of pesticides decrease the growth rate of fermentative microbiota (yeasts and bacterias), which provokes stuck and sluggish fermentations. These changes have in consequence repercussions on several aspects of food sensory quality (physical-chemical properties, polyphenolic content, and aromatic profile) of fermented food. The main aim of this review is to deal with all these topics to propose challenging needs in science-based quality management of pesticides residues in food.

  7. Effects of milk fermented by Lactobacillus helveticus R389 on a murine breast cancer model

    PubMed Central

    de Moreno de LeBlanc, Alejandra; Matar, Chantal; LeBlanc, Nicole; Perdigón, Gabriela

    2005-01-01

    Introduction Antitumour activity is one of the health-promoting effects attributed to the lactic acid bacteria and their products of fermentation. Previous studies in mice demonstrated that bioactive compounds released in milk fermented by Lactobacillus helveticus R389 contribute to its immunoenhancing and antitumour properties. The aim of the present work was to study the effects of the consumption of milk fermented by L. helveticus R389 or its proteolytic-deficient variant, L. helveticus L89, on a murine hormone-dependent breast cancer model. Methods Mice were fed with milk fermented by L. helveticus R389 or L. helveticus L89, during 2 or 7 days. The tumour control group received no special feeding. At the end of the feeding period, the mice were challenged by a subcutaneous injection of tumour cells in the mammary gland. Four days post-injection, the mice received fermented milk on a cyclical basis. The rate of tumour development and the cytokines in serum, mammary gland tissue and tumour-isolated cells were monitored. Bcl-2-positive cells in mammary glands and cellular apoptosis in tumour tissue were also studied. Results Seven days of cyclical administration of milk fermented by either bacterial strain delayed or stopped the tumour development. Cytokines demonstrated that L. helveticus R389 modulated the immune response challenged by the tumour. IL-10 and IL-4 were increased in all the samples from this group. In comparison with the tumour control, all test groups showed a decrease of IL-6, a cytokine involved in oestrogen synthesis. Seven days of cyclical feeding with milk fermented by L. helveticus R389 produced an increase in the number of apoptotic cells, compared with all other groups. Conclusion This study demonstrated that 7 days of cyclical administration of milk fermented by both strains of L. helveticus diminishes tumour growth, stimulating an antitumour immune response. Compounds released during milk fermentation with L. helveticus R389 would be

  8. Appropriate vacuolar acidification in Saccharomyces cerevisiae is associated with efficient high sugar fermentation.

    PubMed

    Nguyen, Trung D; Walker, Michelle E; Gardner, Jennifer M; Jiranek, Vladimir

    2018-04-01

    Vacuolar acidification serves as a homeostatic mechanism to regulate intracellular pH, ion and chemical balance, as well as trafficking and recycling of proteins and nutrients, critical for normal cellular function. This study reports on the importance of vacuole acidification during wine-like fermentation. Ninety-three mutants (homozygous deletions in lab yeast strain, BY4743), which result in protracted fermentation when grown in a chemically defined grape juice with 200 g L -1 sugar (pH 3.5), were examined to determine whether fermentation protraction was in part due to a dysfunction in vacuolar acidification (VA) during the early stages of fermentation, and whether VA was responsive to the initial sugar concentration in the medium. Cells after 24 h growth were dual-labelled with propidium iodide and vacuolar specific probe 6-carboxyfluorescein diacetate (6-CFDA) and examined with a FACS analyser for viability and impaired VA, respectively. Twenty mutants showed a greater than two-fold increase in fluorescence intensity; the experimental indicator for vacuolar dysfunction; 10 of which have not been previously annotated to this process. With the exception of Δhog1, Δpbs2 and Δvph1 mutants, where dysfunction was directly related to osmolality; the remainder exhibited increased CF-fluorescence, independent of sugar concentration at 20 g L -1 or 200 g L -1 . These findings offer insight to the importance of VA to cell growth in high sugar media. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. Mode of Birth Influences Preterm Infant Intestinal Colonization with Bacteroides Over the Early Neonatal Period

    PubMed Central

    Gregory, Katherine E.; LaPlante, Rose D.; Shan, Gururaj; Kumar, Deepak Vijaya; Gregas, Matt

    2015-01-01

    Background Intestinal colonization during infancy is important to short and long term health outcomes. Bacteroides, an early member of the intestinal microbiome, are necessary for breaking down complex molecules within the intestine and function to assist the body’s immune system in fighting against potentially harmful pathogens. Little is known about the colonization pattern of Bacteroides in preterm infants during the early neonatal period. Purpose This study measured Bacteroides colonization during the early neonatal period in a population of preterm infants based on clinical factors including mode of birth, antibiotics, and nutrition. Methods Bacterial DNA was isolated from 144 fecal samples from 29 preterm infants and analyzed using quantitative real time polymerase chain reaction (PCR). Analyses included liner mixed models to determine which clinical factors affect Bacteroides colonization of the infant gut. Results We found that infants born via vaginal canal had a higher rate of increase in Bacteroides than infants born via Cesarean section (p<.001). We did not find significant associations between antibiotic administration and differences in nutritional exposures with Bacteroides colonization. Implications for Practice These findings highlight the significant influence of mode of birth on Bacteroides colonization. While mode of birth is not always modifiable, these study findings may help develop interventions for preterm infants born via Cesarean section aimed at overcoming delayed Bacteroides colonization. Implications for Research Greater study of the intestinal microbiome and the clinical factors relevant to the preterm infant is needed so that interventions may be developed and tested, resulting in optimal microbial and immune health. PMID:26551793

  10. Fermented dairy food and CVD risk.

    PubMed

    Tapsell, Linda C

    2015-04-01

    Fermented dairy foods such as yoghurt and cheese are commonly found in the Mediterranean diet. Recent landmark research has confirmed the effect of the Mediterranean diet on reducing the CVD risk, but the relative contributions of fermented dairy foods have not been fully articulated. The present study provides a review of the relationship between fermented dairy foods consumption and CVD risk in the context of the whole diet. Studies show that people who eat healthier diets may be more likely to consume yoghurt, so there is a challenge in attributing separate effects to yoghurt. Analyses from large population studies list yoghurt as the food most negatively associated with the risk of weight gain (a problem that may lead to CVD). There is some suggestion that fermented dairy foods consumption (yoghurt or cheese) may be associated with reduced inflammatory biomarkers associated with the development of CVD. Dietary trials suggest that cheese may not have the same effect on raising LDL-cholesterol levels as butter with the same saturated fat content. The same might be stated for yoghurt. The use of different probiotic cultures and other aspects of study design remain a problem for research. Nevertheless, population studies from a range of countries have shown that a reduced risk of CVD occurs with the consumption of fermented dairy foods. A combination of evidence is necessary, and more research is always valuable, but indications remain that fermented dairy foods such as cheese and yoghurt are integral to diets that are protective against CVD.

  11. Effect of milk fermentation by kefir grains and selected single strains of lactic acid bacteria on the survival of Mycobacterium bovis BCG.

    PubMed

    Macuamule, C L S; Wiid, I J; van Helden, P D; Tanner, M; Witthuhn, R C

    2016-01-18

    Mycobacterium bovis that causes Bovine tuberculosis (BTB) can be transmitted to humans thought consumption of raw and raw fermented milk products from diseased animals. Lactic acid bacteria (LAB) used in popular traditional milk products in Africa produce anti-microbial compounds that inhibit some pathogenic and spoilage bacteria. M. bovis BCG is an attenuated non-pathogenic vaccine strain of M. bovis and the aim of the study was to determine the effect of the fermentation process on the survival of M. bovis BCG in milk. M. bovis BCG at concentrations of 6 log CFU/ml was added to products of kefir fermentation. The survival of M. bovis BCG was monitored at 12-h intervals for 72 h by enumerating viable cells on Middlebrook 7H10 agar plates enriched with 2% BD BACTEC PANTA™. M. bovis BCG was increasingly reduced in sterile kefir that was fermented for a period of 24h and longer. In the milk fermented with kefir grains, Lactobacillus paracasei subsp. paracasei or Lactobacillus casei, the viability of M. bovis BCG was reduced by 0.4 logs after 24h and by 2 logs after 48 h of fermentation. No viable M. bovis BCG was detected after 60 h of fermentation. Results from this study show that long term fermentation under certain conditions may have the potential to inactivate M. bovis BCG present in the milk. However, to ensure safety of fermented milk in Africa, fermentation should be combined with other hurdle technologies such as boiling and milk pasteurisation. Copyright © 2015 Elsevier B.V. All rights reserved.

  12. Monascus pigment production by solid-state fermentation with corn cob substrate.

    PubMed

    Velmurugan, Palanivel; Hur, Hyun; Balachandar, Vellingiri; Kamala-Kannan, Seralathan; Lee, Kui-Jae; Lee, Sang-Myung; Chae, Jong-Chan; Shea, Patrick J; Oh, Byung-Taek

    2011-12-01

    Natural pigments are an important alternative to potentially harmful synthetic dyes. We investigated the feasibility of corn cob powder as a substrate for production of pigments by Monascus purpureus KACC 42430 in solid-state fermentation. A pigment yield of 25.42 OD Units/gram of dry fermented substrate was achieved with corn cob powder and optimized process parameters, including 60% (w/w) initial moisture content, incubation at 30°C, inoculation with 4mL of spores/gram of dry substrate, and an incubation period of 7 days. Pigment yield using corn cobs greatly exceeded those of most other agricultural waste substrates. The pigments were stable at acidic pH, high temperatures, and in salt solutions; all important considerations for industrial applications. Our results indicate the viability of corn cob substrate in combination with M. purpureus for industrial applications. Copyright © 2011 The Society for Biotechnology, Japan. All rights reserved.

  13. Isolation of a novel alginate lyase-producing Bacillus litoralis strain and its potential to ferment Sargassum horneri for biofertilizer.

    PubMed

    Wang, Mingpeng; Chen, Lei; Liu, Zhengyi; Zhang, Zhaojie; Qin, Song; Yan, Peisheng

    2016-12-01

    Algae have long been used to augment plant productivity through their beneficial effects. Alginate oligosaccharide is believed to be one of the important components to enhance growth and crop yield. In this study, we isolated and characterized a Bacillus litoralis strain, named Bacillus M3, from decayed kelps. We further demonstrated that the M3 strain could secrete alginate lyase to degrade alginate. The crude enzyme exhibited the highest activity (33.74 U/mg) at pH 7.0 and 50°C. The M3 strain was also able to ferment the brown alga Sargassum horneri. Fermentation results revealed that a fermentation period of 8-12 hr was the best harvest time with the highest level of alginate oligosaccharides. Plant growth assay showed that the seaweed fermentation extract had an obvious promotion effect on root and seedling growth of Lycopersicon eseulentum L. Our results suggest that fermentation extract of Sargassum horneri by the novel strain of Bacillus litoralis M3 has significant development potential for biofertilizer production and agriculture application. © 2016 The Authors. MicrobiologyOpen published by John Wiley & Sons Ltd.

  14. The influence of narrow-leafed lupin seed fermentation on their chemical composition and ileal digestibility and microbiota in growing pigs.

    PubMed

    Zaworska, Anita; Frankiewicz, Andrzej; Kasprowicz-Potocka, Małgorzata

    2017-08-01

    The aims of this study were to provide a controlled fermentation process of blue lupin seeds (Lupinus angustifolius, cv. Neptun), monitor the changes in seed composition and determine the influence of the fermentation on the apparent ileal digestibility (AID) of crude protein (CP) and amino acids in growing pigs, compared with raw lupin seeds. The fermentation with bacteria and yeast was conducted for 24 h at 25ºC under aerobic conditions. Seed fermentation increased the contents of CP, fibre, fat and ash and most of the analysed amino acids but reduced the levels of the nitrogen-free extractives. Furthermore, fermentation decreased the contents of raffinose family oligosaccharides and phytic acids but increased the alkaloid content. The AID was estimated on three barrows (mean initial body weight 25 kg), surgically fitted with a T-cannula in the distal ileum. The pigs received three diets, each for 6 d, within three experimental periods (3 × 3 Latin Square design). The diets contained soybean meal (Group SBM), raw lupin seeds (Group RL) or fermented lupin seeds (Group FL) as solely protein sources. Fermentation had a positive impact on the AID of CP and methionine, cysteine, isoleucine, leucine, phenylalanine and valine (p < 0.05). Feeding raw or fermented lupin seeds did not affect the microbial status of the ileal digesta. Moreover, ammonia content in the caecal digesta did not differ between Groups RL and FL, although it was significantly higher than in Group SBM. It can be concluded that the fermentation process modified the chemical composition of nutrients in seeds, which can influence the digestibility and utilisation of the fermentation product in animal diets compared to raw seeds.

  15. Fermented probiotic beverages based on acid whey.

    PubMed

    Skryplonek, Katarzyna; Jasińska, Małgorzata

    2015-01-01

    Production of fermented probiotic beverages can be a good method for acid whey usage. The obtained products combine a high nutritional value of whey with health benefits claimed for probiotic bacteria. The aim of the study was to define quality properties of beverages based on fresh acid whey and milk with addition of buttermilk powder or sweet whey powder. Samples were inoculated with two strains of commercial probiotic cultures: Lactobacillus acidophilus La-5 or Bifidobacterium animalis Bb-12. After fermentation, samples were stored at refrigerated conditions. After 1, 4, 7, 14 and 21 days sensory characteristics, hardness, acetaldehyde content, titratable acidity, pH acidity and count of bacteria cells were evaluated. Throughout all storage period, the number of bacteria was higher than 8 log cfu/ml in the all samples. Beverages with La-5 strain had higher hardness and acidity, whilst samples with Bb-12 contained more acetaldehyde. Samples with buttermilk powder had better sensory properties than with sweet whey powder. Obtained products made of acid whey combined with milk and fortified with buttermilk powder or sweet whey powder, are good medium for growth and survival of examined probiotic bacteria strains. The level of bacteria was sufficient to provide health benefits to consumers.

  16. Health benefits of fermented foods: microbiota and beyond.

    PubMed

    Marco, Maria L; Heeney, Dustin; Binda, Sylvie; Cifelli, Christopher J; Cotter, Paul D; Foligné, Benoit; Gänzle, Michael; Kort, Remco; Pasin, Gonca; Pihlanto, Anne; Smid, Eddy J; Hutkins, Robert

    2017-04-01

    Fermented foods and beverages were among the first processed food products consumed by humans. The production of foods such as yogurt and cultured milk, wine and beer, sauerkraut and kimchi, and fermented sausage were initially valued because of their improved shelf life, safety, and organoleptic properties. It is increasingly understood that fermented foods can also have enhanced nutritional and functional properties due to transformation of substrates and formation of bioactive or bioavailable end-products. Many fermented foods also contain living microorganisms of which some are genetically similar to strains used as probiotics. Although only a limited number of clinical studies on fermented foods have been performed, there is evidence that these foods provide health benefits well-beyond the starting food materials. Copyright © 2016 Elsevier Ltd. All rights reserved.

  17. Sterilization of fermentation vessels by ethanol/water mixtures

    DOEpatents

    Wyman, C.E.

    1999-02-09

    A method is described for sterilizing process fermentation vessels with a concentrated alcohol and water mixture integrated in a fuel alcohol or other alcohol production facility. Hot, concentrated alcohol is drawn from a distillation or other purification stage and sprayed into the empty fermentation vessels. This sterilizing alcohol/water mixture should be of a sufficient concentration, preferably higher than 12% alcohol by volume, to be toxic to undesirable microorganisms. Following sterilization, this sterilizing alcohol/water mixture can be recovered back into the same distillation or other purification stage from which it was withdrawn. The process of this invention has its best application in, but is not limited to, batch fermentation processes, wherein the fermentation vessels must be emptied, cleaned, and sterilized following completion of each batch fermentation process. 2 figs.

  18. Nutrient and energy content, in vitro ruminal fermentation characteristics and methanogenic potential of alpine forage plant species during early summer.

    PubMed

    Jayanegara, Anuraga; Marquardt, Svenja; Kreuzer, Michael; Leiber, Florian

    2011-08-15

    Plants growing on alpine meadows are reported to be rich in phenols. Such compounds may affect ruminal fermentation and reduce the plants' methanogenic potential, making alpine grazing advantageous in this respect. The objective of this study was to quantify nutrients and phenols in Alpine forage grasses, herbs and trees collected over 2 years and, in a 24 h in vitro incubation, their effects on ruminal fermentation parameters. The highest in vitro gas production, resulting in metabolisable energy values around 10 MJ kg⁻¹, were found with Alchemilla xanthochlora and Crepis aurea (herbaceous species) and with Sambucus nigra leaves and flowers (tree species). Related to the amount of total gas production, methane formation was highest with Nardus stricta, and lowest with S. nigra and A. xanthochlora. In addition, Castanea sativa leaves led to an exceptional low methane production, but this was accompanied by severely impaired ruminal fermentation. When the data were analysed by principal component analysis, phenol concentrations were negatively related with methane proportion in total gas. Variation in methane production potential across the investigated forages was small. The two goals of limited methane production potential and high nutritive value for ruminants were met best by A. xanthochlora and S. nigra. Copyright © 2011 Society of Chemical Industry.

  19. Ethanol Production and Maximum Cell Growth Are Highly Correlated with Membrane Lipid Composition during Fermentation as Determined by Lipidomic Analysis of 22 Saccharomyces cerevisiae Strains

    PubMed Central

    Henderson, Clark M.; Lozada-Contreras, Michelle; Jiranek, Vladimir; Longo, Marjorie L.

    2013-01-01

    Optimizing ethanol yield during fermentation is important for efficient production of fuel alcohol, as well as wine and other alcoholic beverages. However, increasing ethanol concentrations during fermentation can create problems that result in arrested or sluggish sugar-to-ethanol conversion. The fundamental cellular basis for these problem fermentations, however, is not well understood. Small-scale fermentations were performed in a synthetic grape must using 22 industrial Saccharomyces cerevisiae strains (primarily wine strains) with various degrees of ethanol tolerance to assess the correlation between lipid composition and fermentation kinetic parameters. Lipids were extracted at several fermentation time points representing different growth phases of the yeast to quantitatively analyze phospholipids and ergosterol utilizing atmospheric pressure ionization-mass spectrometry methods. Lipid profiling of individual fermentations indicated that yeast lipid class profiles do not shift dramatically in composition over the course of fermentation. Multivariate statistical analysis of the data was performed using partial least-squares linear regression modeling to correlate lipid composition data with fermentation kinetic data. The results indicate a strong correlation (R2 = 0.91) between the overall lipid composition and the final ethanol concentration (wt/wt), an indicator of strain ethanol tolerance. One potential component of ethanol tolerance, the maximum yeast cell concentration, was also found to be a strong function of lipid composition (R2 = 0.97). Specifically, strains unable to complete fermentation were associated with high phosphatidylinositol levels early in fermentation. Yeast strains that achieved the highest cell densities and ethanol concentrations were positively correlated with phosphatidylcholine species similar to those known to decrease the perturbing effects of ethanol in model membrane systems. PMID:23064336

  20. Ethanol production and maximum cell growth are highly correlated with membrane lipid composition during fermentation as determined by lipidomic analysis of 22 Saccharomyces cerevisiae strains.

    PubMed

    Henderson, Clark M; Lozada-Contreras, Michelle; Jiranek, Vladimir; Longo, Marjorie L; Block, David E

    2013-01-01

    Optimizing ethanol yield during fermentation is important for efficient production of fuel alcohol, as well as wine and other alcoholic beverages. However, increasing ethanol concentrations during fermentation can create problems that result in arrested or sluggish sugar-to-ethanol conversion. The fundamental cellular basis for these problem fermentations, however, is not well understood. Small-scale fermentations were performed in a synthetic grape must using 22 industrial Saccharomyces cerevisiae strains (primarily wine strains) with various degrees of ethanol tolerance to assess the correlation between lipid composition and fermentation kinetic parameters. Lipids were extracted at several fermentation time points representing different growth phases of the yeast to quantitatively analyze phospholipids and ergosterol utilizing atmospheric pressure ionization-mass spectrometry methods. Lipid profiling of individual fermentations indicated that yeast lipid class profiles do not shift dramatically in composition over the course of fermentation. Multivariate statistical analysis of the data was performed using partial least-squares linear regression modeling to correlate lipid composition data with fermentation kinetic data. The results indicate a strong correlation (R(2) = 0.91) between the overall lipid composition and the final ethanol concentration (wt/wt), an indicator of strain ethanol tolerance. One potential component of ethanol tolerance, the maximum yeast cell concentration, was also found to be a strong function of lipid composition (R(2) = 0.97). Specifically, strains unable to complete fermentation were associated with high phosphatidylinositol levels early in fermentation. Yeast strains that achieved the highest cell densities and ethanol concentrations were positively correlated with phosphatidylcholine species similar to those known to decrease the perturbing effects of ethanol in model membrane systems.

  1. Effect of high intensity ultrasound on the fermentation profile of Lactobacillus sakei in a meat model system.

    PubMed

    Ojha, Kumari Shikha; Kerry, Joseph P; Alvarez, Carlos; Walsh, Des; Tiwari, Brijesh K

    2016-07-01

    The objective of this study was to investigate the efficacy of high intensity ultrasound on the fermentation profile of Lactobacillus sakei in a meat model system. Ultrasound power level (0-68.5 W) and sonication time (0-9 min) at 20 °C were assessed against the growth of L. sakei using a Microplate reader over a period of 24h. The L. sakei growth data showed a good fit with the Gompertz model (R(2)>0.90; SE<0.042). Second order polynomial models demonstrated the effect of ultrasonic power and sonication time on the specific growth rate (SGR, μ, h(-1)) and lag phase (λ, h). A higher SGR and a shorter lag phase were observed at low power (2.99 W for 5 min) compared to control. Conversely, a decrease (p<0.05) in SGR with an increase in lag phase was observed with an increase in ultrasonic power level. Cell-free extracts obtained after 24h fermentation of ultrasound treated samples showed antimicrobial activity against Staphylococcus aureus, Listeria monocytogenes, Escherichia coli and Salmonella typhimurium at lower concentrations compared to control. No significant difference (p<0.05) among treatments was observed for lactic acid content after a 24h fermentation period. This study showed that both stimulation and retardation of L. sakei is possible, depending on the ultrasonic power and sonication time employed. Hence, fermentation process involving probiotics to develop functional food products can be tailored by selection of ultrasound processing parameters. Copyright © 2016 Elsevier B.V. All rights reserved.

  2. Fermentation strategy for second generation ethanol production from sugarcane bagasse hydrolyzate by Spathaspora passalidarum and Scheffersomyces stipitis.

    PubMed

    Nakanishi, Simone C; Soares, Lauren B; Biazi, Luiz Eduardo; Nascimento, Viviane M; Costa, Aline C; Rocha, George Jackson M; Ienczak, Jaciane L

    2017-10-01

    Alcoholic fermentation of released sugars in pretreatment and enzymatic hydrolysis of biomass is a central feature for second generation ethanol (E2G) production. Saccharomyces cerevisiae used industrially in the production of first generation ethanol (E1G) convert sucrose, fructose, and glucose into ethanol. However, these yeasts have no ability to ferment pentose (xylose). Therefore, the present work has focused on E2G production by Scheffersomyces stipitis and Spathaspora passalidarum. The fermentation strategy with high pitch, cell recycle, fed-batch mode, and temperature decrease for each batch were performed in a hydrolyzate obtained from a pretreatment at 130°C with NaOH solution (1.5% w/v) added with 0.15% (w/w) of anthraquinone (AQ) and followed by enzymatic hydrolysis. The process strategy has increased volumetric productivity from 0.35 to 0.38 g · L -1  · h -1 (first to third batch) for S. stipitis and from 0.38 to 0.81 g · L -1  · h -1 for S. passalidarum (first to fourth batch). Mass balance for the process proposed in this work showed the production of 177.33 kg ethanol/ton of sugar cane bagasse for S. passalidarum compared to 124.13 kg ethanol/ton of sugar cane bagasse for S. stipitis fermentation. The strategy proposed in this work can be considered as a promising strategy in the production of second generation ethanol. Biotechnol. Bioeng. 2017;114: 2211-2221. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  3. Fermentation Industry.

    ERIC Educational Resources Information Center

    Grady, C. P. L., Jr.; Grady, J. K.

    1978-01-01

    Presents a literature review of wastes from the fermentation industry, covering publications of 1976-77. This review focuses on: (1) alcoholic beverage production; (2) pharmaceuticals and biochemicals production; and (3) biomass production. A list of 62 references is also presented. (HM)

  4. Fermentation of cucumbers brined with calcium chloride instead of sodium chloride.

    PubMed

    McFeeters, Roger F; Pérez-Díaz, Ilenys

    2010-04-01

    Waste water containing high levels of NaCl from cucumber fermentation tank yards is a continuing problem for the pickled vegetable industry. A major reduction in waste salt could be achieved if NaCl were eliminated from the cucumber fermentation process. The objectives of this project were to ferment cucumbers in brine containing CaCl(2) as the only salt, to determine the course of fermentation metabolism in the absence of NaCl, and to compare firmness retention of cucumbers fermented in CaCl(2) brine during subsequent storage compared to cucumbers fermented in brines containing both NaCl and CaCl(2) at concentrations typically used in commercial fermentations. The major metabolite changes during fermentation without NaCl were conversion of sugars in the fresh cucumbers primarily to lactic acid which caused pH to decrease to less than 3.5. This is the same pattern that occurs when cucumbers are fermented with NaCl as the major brining salt. Lactic acid concentration and pH were stable during storage and there was no detectable production of propionic acid or butyric acid that would indicate growth of spoilage bacteria. Firmness retention in cucumbers fermented with 100 to 300 mM CaCl(2) during storage at a high temperature (45 degrees C) was not significantly different from that obtained in fermented cucumbers with 1.03 M NaCl and 40 mM CaCl(2). In closed jars, cucumber fermentations with and without NaCl in the fermentation brine were similar both in the chemical changes caused by the fermentative microorganisms and in the retention of firmness in the fermented cucumbers.

  5. A Novel simultaneous-Saccharification-Fermentation Strategy for Efficient Co-fermentation of C5 and C6 Sugars Using Native, Non-GMO Yeasts

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Varanasi, Sasidhar; Relue, Patricia

    Economic bioethanol production is critically dependent upon the ability to convert both the hexose (C6) and pentose (C5) sugars resulting from cellulose and hemicellulose. C5 sugars are not readily fermentable by native Saccharomyces cerevisiae. Genetically Modified Organisms (GMOs) are designed to ferment xylose, but their stability, ethanol yield, environmental impact, and survival under conditions of industrial fermentation are unproven. In this project, we developed a novel approach for efficient fermentation of both C5 and C6 sugars using native S. Cerevisiae by exploiting its ability to produce ethanol from xylulose - the keto-isomer of xylose. While the isomerization of xylose tomore » xylulose can be accomplished via commercially (and cheaply) available Xylose Isomerase (XI) (Sweetzyme™), this conversion has an extremely unfavorable equilibrium (xylose:xylose is about 5:1). To address this, we developed two alternate strategies. In the first, the two enzymes XI and urease are coimmobilized on solid support particles to enable complete isomerization of xylose to xylulose under pH conditions suitable for fermentation, in a simultaneous-isomerization-fermentation (SIF) mode. The ability of our technology to conduct isomerization of xylose under pH conditions suitable for both saccharification and fermentation opens the possibility of SSF with native yeasts for the first time. Herein, we performed specific research tasks for implementation of our technology in several modes of operation, including simultaneous-isomerization-and-fermentation (SIF), simultaneous-saccharification-and-isomerization (SSI) followed by fermentation, and SSF mode with the biomass feedstock poplar. The projected economics of our process are very favorable in comparison to the costs associated with engineering, licensing and propagating GMOs. This novel fermentation technology is readily accessible to rural farming economies for implementation in cellulosic ethanol production

  6. Generalised additive modelling approach to the fermentation process of glutamate.

    PubMed

    Liu, Chun-Bo; Li, Yun; Pan, Feng; Shi, Zhong-Ping

    2011-03-01

    In this work, generalised additive models (GAMs) were used for the first time to model the fermentation of glutamate (Glu). It was found that three fermentation parameters fermentation time (T), dissolved oxygen (DO) and oxygen uptake rate (OUR) could capture 97% variance of the production of Glu during the fermentation process through a GAM model calibrated using online data from 15 fermentation experiments. This model was applied to investigate the individual and combined effects of T, DO and OUR on the production of Glu. The conditions to optimize the fermentation process were proposed based on the simulation study from this model. Results suggested that the production of Glu can reach a high level by controlling concentration levels of DO and OUR to the proposed optimization conditions during the fermentation process. The GAM approach therefore provides an alternative way to model and optimize the fermentation process of Glu. Crown Copyright © 2010. Published by Elsevier Ltd. All rights reserved.

  7. Bioprocess Intensification of Beer Fermentation Using Immobilised Cells

    NASA Astrophysics Data System (ADS)

    Verbelen, Pieter J.; Nedović, Viktor A.; Manojlović, Verica; Delvaux, Freddy R.; Laskošek-Čukalović, Ida; Bugarski, Branko; Willaert, Ronnie

    Beer production with immobilised yeast has been the subject of research for approximately 30 years but has so far found limited application in the brewing industry, due to engineering problems, unrealised cost advantages, microbial contaminations and an unbalanced beer flavor (Linko et al. 1998; Brányik et al. 2005; Willaert and Nedović 2006). The ultimate aim of this research is the production of beer of desired quality within 1-3 days. Traditional beer fermentation systems use freely suspended yeast cells to ferment wort in an unstirred batch reactor. The primary fermentation takes approximately 7 days with a subsequent secondary fermentation (maturation) of several weeks. A batch culture system employing immobilization could benefit from an increased rate of fermentation. However, it appears that in terms of increasing productivity, a continuous fermentation system with immobilization would be the best method (Verbelen et al. 2006). An important issue of the research area is whether beer can be produced by immobilised yeast in continuous culture with the same characteristic as the traditional method.

  8. Production and partial characterization of serine and metallo peptidases secreted by Aspergillus fumigatus Fresenius in submerged and solid state fermentation.

    PubMed

    da Silva, Ronivaldo Rodrigues; de Freitas Cabral, Tatiana Pereira; Rodrigues, André; Cabral, Hamilton

    2013-01-01

    Enzyme production varies in different fermentation systems. Enzyme expression in different fermentation systems yields important information for improving our understanding of enzymatic production induction. Comparative studies between solid-state fermentation (SSF) using agro-industrial waste wheat bran and submerged fermentation (SmF) using synthetic media were carried out to determinate the best parameters for peptidase production by the fungus Aspergillus fumigatus Fresen. Variables tested include: the concentration of carbon and protein nitrogen sources, the size of the inoculum, the pH of the media, temperature, and the length of the fermentation process. The best peptidase production during SSF was obtained after 96 hours using wheat bran at 30 °C with an inoculum of 1 × 10(6) spores and yielded 1500 active units (U/mL). The best peptidase production using SmF was obtained after periods of 72 and 96 hours of fermentation in media containing 0.5% and 0.25% of casein, respectively, at a pH of 6.0 and at 30 °C and yielded 40 U/mL. We also found examples of catabolite repression of peptidase production under SmF conditions. Biochemical characterization of the peptidases produced by both fermentative processes showed optimum activity at pH 8.0 and 50 °C, and also showed that their proteolytic activity is modulated by surfactants. The enzymatic inhibition profile using phenylmethylsulfonyl fluoride (PMSF) in SmF and SSF indicated that both fermentative processes produced a serine peptidase. Additionally, the inhibitory effect of the ethylene-diaminetetraacetic acid (EDTA) chelating agent on the peptidase produced by SmF indicated that this fermentative process also produced a metallopeptidase.

  9. Fermentation behaviour and volatile compound production by agave and grape must yeasts in high sugar Agave tequilana and grape must fermentations.

    PubMed

    Arrizon, Javier; Fiore, Concetta; Acosta, Guillermina; Romano, Patrizia; Gschaedler, Anne

    2006-01-01

    Few studies have been performed on the characterization of yeasts involved in the production of agave distilled beverages and their individual fermentation properties. In this study, a comparison and evaluation of yeasts of different origins in the tequila and wine industries were carried out for technological traits. Fermentations were carried out in high (300 g l(-1)) and low (30 g l(-1)) sugar concentrations of Agave tequilana juice, in musts obtained from Fiano (white) and Aglianico (red) grapes and in YPD medium (with 270 g l(-1) of glucose added) as a control. Grape yeasts exhibited a reduced performance in high-sugar agave fermentation, while both agave and grape yeasts showed similar fermentation behaviour in grape musts. Production levels of volatile compounds by grape and agave yeasts differed in both fermentations.

  10. Early extubation after cardiac surgery: emotional status in the early postoperative period.

    PubMed

    Silbert, B S; Santamaria, J D; Kelly, W J; O'brien, J L; Blyth, C M; Wong, M Y; Allen, N B

    2001-08-01

    To compare the emotional state during the first 3 days after coronary artery surgery of patients who had undergone early versus conventional extubation. A prospective, randomized, controlled trial. University hospital, single center. Eligible patients (n = 100) presenting for elective coronary artery surgery, randomized to an early extubation group or a conventional extubation group. Emotional status was measured by the Hospital Anxiety and Depression Scale (HAD), the Self Assessment Manikin (SAM), and the Multiple Affect Adjective Check List-Revised (MAACL-R). Tests were administered preoperatively and on the 1st and 3rd days postoperatively. Of patients in the conventional extubation group, 30% showed moderate-to-severe depressive symptoms (HAD score >10) on day 3 postoperatively compared with 8% of patients in the early extubation group (p = 0.02). There was a clinically insignificant increase in MAACL-R depression score on the 1st postoperative day within both groups but no other differences within or between groups in SAM or MAACL-R scores. Early extubation results in fewer patients displaying depressive symptoms on the 3rd postoperative day but appears to have little effect on other measurements of emotional status. Anesthetic management during coronary artery bypass graft surgery may play an important role in the overall well-being of the patient by decreasing the incidence of postoperative depression. Copyright 2001 by W.B. Saunders Company.

  11. Fermentative production of isobutene.

    PubMed

    van Leeuwen, Bianca N M; van der Wulp, Albertus M; Duijnstee, Isabelle; van Maris, Antonius J A; Straathof, Adrie J J

    2012-02-01

    Isobutene (2-methylpropene) is one of those chemicals for which bio-based production might replace the petrochemical production in the future. Currently, more than 10 million metric tons of isobutene are produced on a yearly basis. Even though bio-based production might also be achieved through chemocatalytic or thermochemical methods, this review focuses on fermentative routes from sugars. Although biological isobutene formation is known since the 1970s, extensive metabolic engineering is required to achieve economically viable yields and productivities. Two recent metabolic engineering developments may enable anaerobic production close to the theoretical stoichiometry of 1isobutene + 2CO(2) + 2H(2)O per mol of glucose. One relies on the conversion of 3-hydroxyisovalerate to isobutene as a side activity of mevalonate diphosphate decarboxylase and the other on isobutanol dehydration as a side activity of engineered oleate hydratase. The latter resembles the fermentative production of isobutanol followed by isobutanol recovery and chemocatalytic dehydration. The advantage of a completely biological route is that not isobutanol, but instead gaseous isobutene is recovered from the fermenter together with CO(2). The low aqueous solubility of isobutene might also minimize product toxicity to the microorganisms. Although developments are at their infancy, the potential of a large scale fermentative isobutene production process is assessed. The production costs estimate is 0.9 Euro kg(-1), which is reasonably competitive. About 70% of the production costs will be due to the costs of lignocellulose hydrolysate, which seems to be a preferred feedstock.

  12. Feeding slowly fermentable grains has the potential to ameliorate heat stress in grain-fed wethers.

    PubMed

    Gonzalez-Rivas, P A; DiGiacomo, K; Russo, V M; Leury, B J; Cottrell, J J; Dunshea, F R

    2016-07-01

    During heat stress (HS), livestock reduce metabolic heat production by lowering activity and feed intake. Because this has obvious consequences for productivity, the aim of these experiments was to investigate nutritional methods for reducing digestive metabolic heat production, thereby allowing livestock more opportunity to dissipate excess heat. In the first experiment, the fermentation rates of corn and wheat grains were compared in an in vitro gas production system containing buffered rumen fluid. This experiment showed that corn had a slower (-15%; < 0.001) rate of gas production than wheat and no differences in total amount of gas production after 24 h of incubation. In the second experiment, we hypothesized that the lower rate of fermentation of corn would reduce metabolic heat load in wethers and, in turn, improve tolerance to HS. Twenty-two Merino × Poll Dorset wethers were housed in 2 climate-controlled rooms and were fed either corn grain plus forage (CD; 39% starch) or wheat grain plus forage (WD; 37% starch) during 3 experimental periods: period 1 (P1), which consisted of 7 d of thermoneutral conditions (18 to 21°C and 40 to 50% relative humidity [RH]) and restricted feed intake (1.3 times maintenance); period 2 (P2), which consisted of 7 d of HS (28 to 38°C and 30 to 50% RH) and restricted feed intake; and period 3 (P3), which consisted of 7 d of HS as in P2 with unrestricted feed intake (1.5 times maintenance) in a randomized control experiment. Water was offered ad libitum. The level of HS was quantified by increases in rectal temperature (RT), respiration rate (RR), and left and right flank skin temperature (LFT and RFT, respectively) and blood acid-base balance. Rectal temperature, RR, LFT, and RFT were elevated ( < 0.001) during HS, especially when wethers had unrestricted feed intake (P3). Wethers fed CD had lower RR, RT, LFT, and RFT ( < 0.001) than wethers fed WD, and this benefit was greatest during HS (P2 and P3). The reduction in RR with

  13. System for extracting protein from a fermentation product

    DOEpatents

    Lawton, Jr., John Warren; Bootsma, Jason Alan; Lewis, Stephen Michael

    2016-04-26

    A method of producing bioproducts from a feedstock in a system configured to produce ethanol and distillers grains from a fermentation product is disclosed. A system configured to process feedstock into a fermentation product and bioproducts including ethanol and meal is disclosed. A bioproduct produced from a fermentation product produced from a feedstock in a biorefining system is disclosed.

  14. Method for extracting protein from a fermentation product

    DOEpatents

    Lawton, Jr., John Warren; Bootsma, Jason Alan; Lewis, Stephen Michael

    2014-02-18

    A method of producing bioproducts from a feedstock in a system configured to produce ethanol and distillers grains from a fermentation product is disclosed. A system configured to process feedstock into a fermentation product and bioproducts including ethanol and meal is disclosed. A bioproduct produced from a fermentation product produced from a feedstock in a biorefining system is disclosed.

  15. Quality of Bread Supplemented with Antrodia
salmonea-Fermented Grains

    PubMed Central

    Chien, Rao-Chi; Ulziijargal, Enkhjargal

    2016-01-01

    Summary Fermented grains of buckwheat, oat, embryo rice and wheat, which were prepared by solid-state fermentation with Antrodia salmonea, and the mycelium was used to substitute 7% of wheat flour to make bread. No difference in proximate composition, texture profile and contents of non-volatile taste components was observed among bread samples. White bread and bread supplemented with mycelium and fermented grains looked different. Bread supplemented with fermented grains had similar thermal properties, which differed from those of white bread and bread supplemented with mycelium. Bread supplemented with fermented grains contained substantial mass fractions (on dry mass basis) of adenosine (0.92–1.96 µg/g), ergosterol (24.53–30.12 µg/g), ergothioneine (2.16–3.18 µg/g) and γ-aminobutyric acid (2.20–2.45 µg/g). In addition, bread supplemented with mycelium contained lovastatin (0.43 µg/g). White bread and bread supplemented with fermented grains had similar sensory results. Overall, fermented grains could be incorporated into bread to provide beneficial effects. PMID:27904408

  16. Prediction of problematic wine fermentations using artificial neural networks.

    PubMed

    Román, R César; Hernández, O Gonzalo; Urtubia, U Alejandra

    2011-11-01

    Artificial neural networks (ANNs) have been used for the recognition of non-linear patterns, a characteristic of bioprocesses like wine production. In this work, ANNs were tested to predict problems of wine fermentation. A database of about 20,000 data from industrial fermentations of Cabernet Sauvignon and 33 variables was used. Two different ways of inputting data into the model were studied, by points and by fermentation. Additionally, different sub-cases were studied by varying the predictor variables (total sugar, alcohol, glycerol, density, organic acids and nitrogen compounds) and the time of fermentation (72, 96 and 256 h). The input of data by fermentations gave better results than the input of data by points. In fact, it was possible to predict 100% of normal and problematic fermentations using three predictor variables: sugars, density and alcohol at 72 h (3 days). Overall, ANNs were capable of obtaining 80% of prediction using only one predictor variable at 72 h; however, it is recommended to add more fermentations to confirm this promising result.

  17. A membrane-integrated fermentation reactor system: its effects in reducing the amount of sub-raw materials for D-lactic acid continuous fermentation by Sporolactobacillus laevolacticus.

    PubMed

    Mimitsuka, Takashi; Na, Kyungsu; Morita, Ken; Sawai, Hideki; Minegishi, Shinichi; Henmi, Masahiro; Yamada, Katsushige; Shimizu, Sakayu; Yonehara, Tetsu

    2012-01-01

    Continuous fermentation by retaining cells with a membrane-integrated fermentation reactor (MFR) system was found to reduce the amount of supplied sub-raw material. If the amount of sub-raw material can be reduced, continuous fermentation with the MFR system should become a more attractive process for industrialization, due to decreased material costs and loads during the refinement process. Our findings indicate that the production rate decreased when the amount of the sub-raw material was reduced in batch fermentation, but did not decrease during continuous fermentation with Sporolactobacillus laevolacticus. Moreover, continuous fermentation with a reduced amount of sub-raw material resulted in a productivity of 11.2 g/L/h over 800 h. In addition, the index of industrial process applicability used in the MFR system increased by 6.3-fold as compared with the conventional membrane-based fermentation reactor previously reported, suggesting a potential for the industrialization of this D-lactic acid continuous fermentation process.

  18. Membrane-mediated extractive fermentation for lactic acid production from cellulosic biomass.

    PubMed

    Chen, R; Lee, Y Y

    1997-01-01

    Lactic acid production from cellulosic biomass by cellulase and Lactobacillus delbrueckii was studied in a fermenter-extractor employing a microporous hollow fiber membrane (MHF). This bioreactor system was operated under a fed-batch mode with continuous removal of lactic acid by anin situ extraction. A tertiary amine (Alamine 336) was used as an extractant for lactic acid. The extraction capacity of Alamine 336 is greatly enhanced by addition of alcohol. Long-chain alcohols serve well for this purpose since they are less toxic to micro-organism. Addition of kerosene, a diluent, was necessary to reduce the solvent viscosity. A solvent mixture of 20% Alamine 336, 40% oleyl alcohol, and 40% kerosene was found to be most effective in the extraction of lactic acid. Progressive change of pH from an initial value of 5.0 down to 4.3 has significantly improved the overall performance of the simultaneous saccharification and extractive fermentation over that of constant pH operation. The change of pH was applied to promote cell growth in the early phase, and extraction in the latter phase.

  19. Application of Baechu-Kimchi Powder and GABA-Producing Lactic Acid Bacteria for the Production of Functional Fermented Sausages

    PubMed Central

    Choi, Ji Hun; Kang, Ki Moon

    2017-01-01

    This study was carried out to determine the physicochemical, microbiological, and quality characteristics of a new type of fermented sausage manufactured by incorporating Baechu-kimchi powder and gamma-aminobutyric acid (GABA)-producing lactic acid bacteria (LAB). The LAB count was at the maximum level by day nine of ripening in inoculated sausages, accompanied by a rapid decrease in the pH. The addition of kimchi powder decreased the lightness (L*) and increased the redness (a*) and, yellowness (b*) values, while also significantly increasing the hardness and chewiness of the sausage (p<0.05). Moreover, although the thiobarbituric acid reactive substances values increased in all samples during the study period, this increase was lower in the kimchi-treated samples, indicating a reduction in lipid oxidation. Overall, our results show that the addition of Baechu-kimchi powder to sausages reduced the off-flavor properties and improved the taste profile of the fermented sausage in sensory evaluations. The GABA content of all fermented sausages increased from 17.42-25.14 mg/kg on the third day of fermentation to 60.95-61.47 mg/kg on the thirtieth day. These results demonstrate that Baechu-kimchi powder and GABA-producing LAB could be functional materials in fermented sausage to improve quality characteristics. PMID:29725201

  20. The effect of microbial starter composition on cassava chips fermentation for the production of fermented cassava flour

    NASA Astrophysics Data System (ADS)

    Kresnowati, M. T. A. P.; Listianingrum, Zaenudin, Ahmad; Trihatmoko, Kharisrama

    2015-12-01

    The processing of cassava into fermented cassava flour (fercaf) or the widely known as modified cassava flour (mocaf) presents an alternative solution to improve the competitiveness of local foods and to support national food security. However, the mass production of fercaf is being limited by several problems, among which is the availability of starter cultures. This paper presents the mapping of the effect of microbial starter compositions on the nutritional content of fercaf in order to obtain the suitable nutritional composition. Based on their enzymatic activities, the combination of Lactobacillus plantarum, Bacillus subtilis, and Aspergillus oryzae were tested during the study. In addition, commercial starter was also tested. During the fermentation, the dynamics in microbial population were measured as well as changes in cyanogenic glucoside content. The microbial starter composition was observed to affect the dynamics in microbial populationcynaogenic glucoside content of the produced fercaf. In general, steady state microbial population was reached within 12 hours of fermentation. Cyanogenic glucoside was observed to decrease along the fermentation.

  1. A Guide to Screening for the Early and Periodic Screening, Diagnosis and Treatment Program (EPSDT) Under Medicaid.

    ERIC Educational Resources Information Center

    Frankenburg, William K.; North, A. Frederick, Jr.

    The manual was designed to help public officials, physicians, nurses, and others to plan and implement an Early and Periodic Screening, Diagnosis and Treatment (EPSDT) program under Medicaid. Procedures for carrying out components of an EPSDT program are recommended. Part 1 discusses organization and administration of screening, diagnosis, and…

  2. Probiotic-mediated blueberry (Vaccinium corymbosum L.) fruit fermentation to yield functionalized products for augmented antibacterial and antioxidant activity.

    PubMed

    Oh, Byung-Taek; Jeong, Seong-Yeop; Velmurugan, Palanivel; Park, Jung-Hee; Jeong, Do-Youn

    2017-11-01

    The aim of this study was to investigate the fermentation of blueberry fruit with selected probiotic bacteria (Bacillus amyloliquefaciens and Lactobacillus brevis) and yeast (Starmerella bombicola) isolated from fermented starfish for the extraction of functionalized products for biomedical applications. All probiotic-based fermented extracts showed augmented antibacterial and antioxidant activity compared to the control. Biochemical parameters of viable cell count, titratable acidity, total phenol, total anthocyanin, total flavonoids, total sugar, and reducing sugar were analyzed during a 0-96 h fermentation period. In addition, Fourier transform infrared (FTIR) spectroscopy was performed to determine the functional groups in the control and fermented extracts and it signifies the presence of alcohol groups, phenol groups, carboxylic acids, and aliphatic amines, respectively. The well diffusion, minimum inhibitory concentration (MIC), and minimum bactericidal concentration (MBC) assays determined that the S. bombicola-mediated fermented extract has excellent activity, followed by B. amyloliquefaciens and L. brevis, at a high concentration of 1.0 g/mL fermented extract. The ABTS and DPPH showed significant scavenging activity with IC 50 values of (30.52 ± 0.08)/(155.10 ± 0.06) μg/mL, (24.82 ± 0.16)/(74.21 ± 1.26) μg/mL, and (21.81 ± 0.08)/(125.11 ± 0.04) μg/mL for B. amyloliquefaciens, L. brevis, and S. bombicola, respectively. Developing a value-added fermented blueberry product will help circumvent losses because of the highly perishable nature of the fruit. Copyright © 2017 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  3. Comparison of biotransformation of inorganic selenium by Lactobacillus and Saccharomyces in lactic fermentation process of yogurt and kefir.

    PubMed

    Alzate, A; Fernández-Fernández, A; Pérez-Conde, M C; Gutiérrez, A M; Cámara, C

    2008-09-24

    The aim of the present study was to characterize, quantify, and compare the different selenium species that are produced when lactic fermentation with two different types of microorganisms, bacteria (Lactobacillus) and yeast (Saccharomyces), take place to produce yogurt and kefir, respectively, and to study the transformation process of these species as a function of time. These two dairy products were chosen for the study because they are highly consumed in different cultures. Moreover, the microorganisms present in the fermentation processes are different. While the bacteria Lactobacillus is the one responsible for yogurt fermentation, a partnership between bacteria and the yeast Saccharomyces causes kefir fermentation. A comparative study has been carried out by fermenting Se(IV) enriched milk in the presence of both types of microorganisms, where the concentration range studied was from 0.5 to 20 microg g (-1). Enzymatic extraction enabled selenium speciation profiles, obtained by anionic exchange and ion-pairing reversed phase high performance liquid chromatography (IP-RP-HPLC) with inductively coupled plasma mass spectrometry (ICP-MS) detection. Scanning electron microscopy (SEM) applied to the enriched samples showed segregated Se (0), at added concentrations higher than 5 microg g (-1). The main Se species formed depended on the type of microorganism involved in the fermentation process, SeCys 2 and MeSeCys being the main species generated in yogurt and SeMet in kefir. The results obtained are different for both kinds of samples. Lactic fermentation for yogurt produced an increment in selenocystine (SeCys 2) and Se-methylselenocysteine (MeSeCys), while fermentation to produce kefir also incremented the selenomethionine (SeMet) concentration. The Se species are stable for at least 10 and 15 days for kefir and yogurt, respectively. After this period, selenocystine concentration decreased, and the concentration of Se-methylselenocysteine was found to

  4. Coupling limonene formation and oxyfunctionalization by mixed-culture resting cell fermentation.

    PubMed

    Willrodt, Christian; Hoschek, Anna; Bühler, Bruno; Schmid, Andreas; Julsing, Mattijs K

    2015-09-01

    Metabolic engineering strategies mark a milestone for the fermentative production of bulk and fine chemicals. Yet, toxic products and volatile reaction intermediates with low solubilities remain challenging. Prominent examples are artificial multistep pathways like the production of perillyl acetate (POHAc) from glucose via limonene. For POHAc, these limitations can be overcome by mixed-culture fermentations. A limonene biosynthesis pathway and cytochrome P450 153A6 (CYP153A6) as regioselective hydroxylase are used in two distinct recombinant E. coli. POHAc formation from glucose in one recombinant cell was hindered by ineffective coupling of limonene synthesis and low rates of oxyfunctionalization. The optimization of P450 gene expression led to the formation of 6.20 ± 0.06 mg gcdw (-1) POHAc in a biphasic batch cultivation with glucose as sole carbon and energy source. Increasing the spatial proximity between limonene synthase and CYP153A6 by a genetic fusion of both enzymes changed the molar limonene/POHAc ratio from 3.2 to 1.6. Spatial separation of limonene biosynthesis from its oxyfunctionalization improved POHAc concentration 3.3-fold to 21.7 mg L(-1) as compared to a biphasic fermentation. Mixed-cultures of E. coli BL21 (DE3) containing the limonene biosynthesis pathway and E. coli MG1655 harboring either CYP153A6, or alternatively a cymene monooxygenase, showed POHAc formation rates of 0.06 or 0.11 U gcdw (-1) , respectively. This concept provides a novel framework for fermentative syntheses involving toxic, volatile, or barely soluble compounds or pathway intermediates. © 2015 Wiley Periodicals, Inc.

  5. Radioprotective effects of miso (fermented soy bean paste) against radiation in B6C3F1 mice: increased small intestinal crypt survival, crypt lengths and prolongation of average time to death.

    PubMed

    Ohara, M; Lu, H; Shiraki, K; Ishimura, Y; Uesaka, T; Katoh, O; Watanabe, H

    2001-12-01

    The radioprotective effect of miso, a fermentation product from soy bean, was investigated with reference to the survival time, crypt survival and jejunum crypt length in male B6C3F1 mice. Miso at three different fermentation stages (early-, medium- and long-term fermented miso) was mixed in MF diet into biscuits at 10% and was administered from 1 week before irradiation. Animal survival in the long-term fermented miso group was significantly prolonged as compared with the short-term fermented miso and MF cases after 8 Gy of 60Co-gamma-ray irradiation at a dose rate of 2Gy min(-1). Delay in mortality was evident in all three miso groups, with significantly increased survival. At doses of 10 and 12 Gy X-irradiation at a dose rate of 4 Gy min(-1), the treatment with long-term fermented miso significantly increased crypt survival. Also the protective influence against irradiation in terms of crypt lengths in the long-term fermented miso group was significantly greater than in the short-term or medium-term fermented miso and MF diet groups. Thus, prolonged fermentation appears to be very important for protection against radiation effects.

  6. Evolution of free amino acids, biogenic amines and n-nitrosoamines throughout ageing in organic fermented beef.

    PubMed

    Wójciak, Karolina M; Solska, Elżbieta

    2016-01-01

    In recent years, interest in uncured meat products has grown and studies were carried out on the use of substances which could replace nitrites, such as acid whey. In spite of this problem in fermented meat products, there is no information regarding the effects of prolonged ageing on the formation of chemical (nitrosoamines, biogenic amines, secondary lipid oxidation products) and microbiological (L. monocytogenes, S. aureus, OLD) toxicants in fermented beef marinated with acid whey. The aim of this study was to determine the selected pathogenic bacteria, biogenic amines, N-nitrosamines contents in fermented beef subjected to extended ageing. In this study, selected pathogenic bacteria, N-nitrosamines, biogenic amines, amino acids, TBARS values changes during the ageing of fermented beef marinated with acid whey were analyzed in 0-, 2- and 36-month-old samples. The pH values of fermented beef aged for 2 months (5.68, 5.49 and 5.68 respectively) were significantly lower (p < 0.05) than those obtained after the end of the manufacturing ripening period (5.96, 5.97 and 5.74 respectively), which confirmed the effectiveness of the fermentation process of acidification on beef. The high Lactic Acid Bacteria content (5.64-6.30 log cfu/g) confirmed this finding. Histamine was not detected in either of the products. The highest concentration of total biogenic amine (i.e. 1159.0 mg/kg) was found in fermented beef marinated with acid whey, whereas a total of only 209.8 mg/kg, was observed in control beef with nitrate and nitrite. N-nitrosamines were not detected in any of the ageing beef samples. In this study, marinating beef in acid whey did not inhibit the production of biogenic amines in the samples analyzed. The high concentration of FAAs, the potential precursor of BA, could lead to intense peptidase activity. The results obtained indicate that biogenic amines are not direct precursors for nitrosamines formation in fermented beef. The LAB strain from acid whey reduced

  7. Enhanced Ethanol Production from De-Ashed Paper Sludge by Simultaneous Saccharification and Fermentation and Simultaneous Saccharification and Co-Fermentation

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kang, L.; Wang, W.; Pallapolu, V. R.

    2011-11-01

    A previous study demonstrated that paper sludges with high ash contents can be converted to ethanol by simultaneous saccharification and fermentation (SSF) or simultaneous saccharification and co-fermentation (SSCF). High ash content in the sludge, however, limited solid loading in the bioreactor, causing low product concentration. To overcome this problem, sludges were de-ashed before SSF and SSCF. Low ash content in sludges also increased the ethanol yield to the extent that the enzyme dosage required to achieve 70% yield in the fermentation process was reduced by 30%. High solid loading in SSF and SSCF decreased the ethanol yield. High agitation andmore » de-ashing of the sludges were able to restore the part of the yield loss caused by high solid loading. Substitution of the laboratory fermentation medium (peptone and yeast extract) with corn steep liquor did not bring about any adverse effects in the fermentation. Fed-batch operation of the SSCF and SSF using low-ash content sludges was effective in raising the ethanol concentration, achieving 47.8 g/L and 60.0 g/L, respectively.« less

  8. Functional Properties of Microorganisms in Fermented Foods

    PubMed Central

    Tamang, Jyoti P.; Shin, Dong-Hwa; Jung, Su-Jin; Chae, Soo-Wan

    2016-01-01

    Fermented foods have unique functional properties imparting some health benefits to consumers due to presence of functional microorganisms, which possess probiotics properties, antimicrobial, antioxidant, peptide production, etc. Health benefits of some global fermented foods are synthesis of nutrients, prevention of cardiovascular disease, prevention of cancer, gastrointestinal disorders, allergic reactions, diabetes, among others. The present paper is aimed to review the information on some functional properties of the microorganisms associated with fermented foods and beverages, and their health-promoting benefits to consumers. PMID:27199913

  9. Fermentative Production of Cysteine by Pantoea ananatis

    PubMed Central

    Takumi, Kazuhiro; Ziyatdinov, Mikhail Kharisovich; Samsonov, Viktor

    2016-01-01

    ABSTRACT Cysteine is a commercially important amino acid; however, it lacks an efficient fermentative production method. Due to its cytotoxicity, intracellular cysteine levels are stringently controlled via several regulatory modes. Managing its toxic effects as well as understanding and deregulating the complexities of regulation are crucial for establishing the fermentative production of cysteine. The regulatory modes include feedback inhibition of key metabolic enzymes, degradation, efflux pumps, and the transcriptional regulation of biosynthetic genes by a master cysteine regulator, CysB. These processes have been extensively studied using Escherichia coli for overproducing cysteine by fermentation. In this study, we genetically engineered Pantoea ananatis, an emerging host for the fermentative production of bio-based materials, to identify key factors required for cysteine production. According to this and our previous studies, we identified a major cysteine desulfhydrase gene, ccdA (formerly PAJ_0331), involved in cysteine degradation, and the cysteine efflux pump genes cefA and cefB (formerly PAJ_3026 and PAJ_p0018, respectively), which may be responsible for downregulating the intracellular cysteine level. Our findings revealed that ccdA deletion and cefA and cefB overexpression are crucial factors for establishing fermentative cysteine production in P. ananatis and for obtaining a higher cysteine yield when combined with genes in the cysteine biosynthetic pathway. To our knowledge, this is the first demonstration of cysteine production in P. ananatis, which has fundamental implications for establishing overproduction in this microbe. IMPORTANCE The efficient production of cysteine is a major challenge in the amino acid fermentation industry. In this study, we identified cysteine efflux pumps and degradation pathways as essential elements and genetically engineered Pantoea ananatis, an emerging host for the fermentative production of bio-based materials, to

  10. Fermentative Production of Cysteine by Pantoea ananatis.

    PubMed

    Takumi, Kazuhiro; Ziyatdinov, Mikhail Kharisovich; Samsonov, Viktor; Nonaka, Gen

    2017-03-01

    Cysteine is a commercially important amino acid; however, it lacks an efficient fermentative production method. Due to its cytotoxicity, intracellular cysteine levels are stringently controlled via several regulatory modes. Managing its toxic effects as well as understanding and deregulating the complexities of regulation are crucial for establishing the fermentative production of cysteine. The regulatory modes include feedback inhibition of key metabolic enzymes, degradation, efflux pumps, and the transcriptional regulation of biosynthetic genes by a master cysteine regulator, CysB. These processes have been extensively studied using Escherichia coli for overproducing cysteine by fermentation. In this study, we genetically engineered Pantoea ananatis , an emerging host for the fermentative production of bio-based materials, to identify key factors required for cysteine production. According to this and our previous studies, we identified a major cysteine desulfhydrase gene, ccdA (formerly PAJ_0331), involved in cysteine degradation, and the cysteine efflux pump genes cefA and cefB (formerly PAJ_3026 and PAJ_p0018, respectively), which may be responsible for downregulating the intracellular cysteine level. Our findings revealed that ccdA deletion and cefA and cefB overexpression are crucial factors for establishing fermentative cysteine production in P. ananatis and for obtaining a higher cysteine yield when combined with genes in the cysteine biosynthetic pathway. To our knowledge, this is the first demonstration of cysteine production in P. ananatis , which has fundamental implications for establishing overproduction in this microbe. IMPORTANCE The efficient production of cysteine is a major challenge in the amino acid fermentation industry. In this study, we identified cysteine efflux pumps and degradation pathways as essential elements and genetically engineered Pantoea ananatis , an emerging host for the fermentative production of bio-based materials, to

  11. Anti-inflammatory effects of fermented and non-fermented Sophora flavescens: a comparative study

    PubMed Central

    2011-01-01

    Background The roots of Sophora flavescens (Leguminosae) have been used in East Asian countries as an herbal medicine and a food ingredient for thousands of years. The aim of the present study was to investigate the effects of S. flavescens fermentation on endotoxin-induced uveitis (EIU) in rats. Methods EIU was induced in rats via a footpad injection of lipopolysaccharide (LPS). Immediately after the LPS inoculation, fermented and non-fermented extracts of S. flavescens (FSE and NFSE, respectively) were administered orally, and the aqueous humor was collected from both eyes 24 hours later. The anti-inflammatory effects of FSE and NFSE were examined in terms of regulation of nuclear factor kappa B (NF-κB) activation and the expression of interleukin-1β (IL-1β), tumor necrosis factor-α (TNF-α), inducible nitric oxide synthase (iNOS), intercellular cell adhesion molecule (ICAM)-1, and cyclooxygenase-2 (COX-2). The regulation of maleic dialdehyde (MDA) levels and polymorphonuclear cell (PMN) infiltration by FSE and NFSE were also examined. Results Treatment with FSE significantly inhibited LPS-induced increases in IL-1β and TNF-α production and the expression of iNOS, ICAM-1 and COX-2. Moreover, FSE suppressed LPS-induced NF-κB activation, and reduced both MDA levels and infiltration by PMN. Conclusion These results indicate that solid state fermentation may enhance the anti-inflammatory effects of S. flavescens. PMID:22026927

  12. Improved fermentative alcohol production. [Patent application

    DOEpatents

    Wilke, C.R.; Maiorella, B.L.; Blanch, H.W.; Cysewski, G.R.

    1980-11-26

    An improved fermentation process is described for producing alcohol which includes the combination of vacuum fermentation and vacuum distillation. Preferably, the vacuum distillation is carried out in two phases, one a fermentor proper operated at atmospheric pressure and a flash phase operated at reduced pressure with recycle of fermentation brew having a reduced alcohol content to the fermentor, using vapor recompression heating of the flash-pot recycle stream to heat the flash-pot or the distillation step, and using water load balancing (i.e., the molar ratio of water in the fermentor feed is the same as the molar ratio of water in the distillation overhead).

  13. The Effect of Lactobacillus plantarum ATCC 8014 and Lactobacillus acidophilus NCFM Fermentation on Antioxidant Properties of Selected in Vitro Sprout Culture of Orthosiphon aristatus (Java Tea) as a Model Study

    PubMed Central

    Hunaefi, Dase; Akumo, Divine N.; Riedel, Heidi; Smetanska, Iryna

    2012-01-01

    High rosmarinic acid (RA) productivity has been achieved by applying jasmonic acid and yeast extract elicitors to the in vitro sprout culture of Orthosiphon aritatus (IOSC). The highest RA accumulation from three solvents was detected in IOSC after treatment with yeast extract (5 g/L). HPLC analysis clearly confirmed a drastic increase in RA subjected to yeast extract elicitation. Therefore, this yeast extract elicited IOSC was chosen for a lactic acid bacteria (LAB) fermentation study as a model system. This selected IOSC was subjected to different types of LAB fermentations (Lactobacillus plantarum ATCC 8014 and Lactobacillus acidophilus NCFM) for different periods of time 24, 48 and 72 h. The LAB fermentations consisted of solid state fermentations (SSF) and liquid state fermentations (LSF) in a Digital Control Unit (DCU) fermenter system. The aim was to determine the effect of fermentation on the antioxidant properties of the plant extract. Results indicated that all types of LAB fermentation decreased the level of RA and total phenolics, however, a slight increase in total flavonoids and flavonols was observed in SSF samples. HPLC results confirmed that the longer the fermentation, the greater the reduction in RA content. The highest reduction was obtained in the sample of LSF inoculated with L. plantarum for a period of 72 h. The temperature of fermentation (37 °C) was predicted as contributing to the declining level in RA content. The loss in RA was concomitant with a loss of total antioxidant activity (1,1-diphenyl-2-picrylhydrazyl (DPPH) scavenging activity, Trolox Equivalent Antioxidant Capacity (TEAC), and Superoxide Dismutase (SOD)-like activity). These results indicate that RA is the major contributor to the antioxidant activity of this plant. PMID:26787613

  14. Early action to reduce greenhouse gas emissions before the commitment period of the Kyoto protocol: advantages and disadvantages.

    PubMed

    Michaelowa, A; Rolfe, C

    2001-09-01

    Current "business as usual" projections suggest greenhouse gas emissions from industrialized nations will grow substantially over the next decade. However, if it comes into force, the Kyoto Protocol will require industrialized nations to reduce emissions to an average of 5% below 1990 levels in the 2008-2012 period. Taking early action to close this gap has a number of advantages. It reduces the risks of passing thresholds that trigger climate change "surprises." Early action also increases future generations' ability to choose greater levels of climate protection, and it leads to faster reductions of other pollutants. From an economic sense, early action is important because it allows shifts to less carbon-intensive technologies during the course of normal capital stock turnover. Moreover, many options for emission reduction have negative costs, and thus are economically worthwhile, because of paybacks in energy costs, healthcare costs, and other benefits. Finally, early emission reductions enhance the probability of successful ratification and lower the risk of noncompliance with the protocol. We discuss policy approaches for the period prior to 2008. Disadvantages of the current proposals for Credit for Early Action are the possibility of adverse selection due to problematic baseline calculation methods as well as the distributionary impacts of allocating a part of the emissions budget already before 2008. One simple policy without drawbacks is the so-called baseline protection, which removes the disincentive to early action due to the expectation that businesses may, in the future, receive emission rights in proportion to past emissions. It is particularly important to adopt policies that shift investment in long-lived capital stock towards less carbon-intensive technologies and to encourage innovation and technology development that will reduce future compliance costs.

  15. Staphylococcus xylosus fermentation of pork fatty waste: raw material for biodiesel production.

    PubMed

    Marques, Roger Vasques; Paz, Matheus Francisco da; Duval, Eduarda Hallal; Corrêa, Luciara Bilhalva; Corrêa, Érico Kunde

    2016-01-01

    The need for cleaner sources of energy has stirred research into utilising alternate fuel sources with favourable emission and sustainability such as biodiesel. However, there are technical constraints that hinder the widespread use of some of the low cost raw materials such as pork fatty wastes. Currently available technology permits the use of lipolytic microorganisms to sustainably produce energy from fat sources; and several microorganisms and their metabolites are being investigated as potential energy sources. Thus, the aim of this study was to characterise the process of Staphylococcus xylosus mediated fermentation of pork fatty waste. We also wanted to explore the possibility of fermentation effecting a modification in the lipid carbon chain to reduce its melting point and thereby act directly on one of the main technical barriers to obtaining biodiesel from this abundant source of lipids. Pork fatty waste was obtained from slaughterhouses in southern Brazil during evisceration of the carcasses and the kidney casing of slaughtered animals was used as feedstock. Fermentation was performed in BHI broth with different concentrations of fatty waste and for different time periods which enabled evaluation of the effect of fermentation time on the melting point of swine fat. The lowest melting point was observed around 46°C, indicating that these chemical and biological reactions can occur under milder conditions, and that such pre-treatment may further facilitate production of biodiesel from fatty animal waste. Copyright © 2016 Sociedade Brasileira de Microbiologia. Published by Elsevier Editora Ltda. All rights reserved.

  16. Process for protein enrichment of cassava by solid substrate fermentation in rural conditions

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Daubresse, P.; Ntibashirwa, S.; Gheysen, A.

    1987-06-01

    An artisanal static process for protein enrichment of cassava by solid-state fermentation, developed in laboratory and tested on pilot units in Burundi (Central Africa), provides enriched cassava containing 10.7% of dry matter protein versus 1% before fermentation. Cassava chips, processed into granules of 2-4-mm diameter, are moistened (40% water content) and steamed. After cooling to 40 degrees C, cassava is mixed with a nutritive solution containing the inoculum (Rhizopus oryzae, strain MUCL 28627) and providing the following per 100 g dry matter: 3.4 g urea, 1.5 g KH/sub 2/PO/sub 4/, O.8 g MgSO/sub 4/.7H/sub 2/O, and 22.7 g citric acid.more » For the fermentation, cassava, with circa 60% moisture content, is spread in a thin layer (2-3 cm thick) on perforated trays and slid into an aerated humidified enclosure. The incubation lasts more or less 65 hours. The production of protein enriched cassava is 3.26 kg dry matter/square m tray. The effects of the variation of the nutritive solution composition and the inoculum conservation period on the protein production are equally discussed. (Refs. 37).« less

  17. Kinetic modeling of lactic acid production from batch submerged fermentation of cheese whey

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Tango, M.S.A.; Ghaly, A.E.

    1999-12-01

    A kinetic model for the production of lactic acid through batch submerged fermentation of cheese whey using Lactobacillus helveticus was developed. The model accounts for the effect of substrate limitation, substrate inhibition, lactic acid inhibition, maintenance energy and cell death on the cell growth, substrate utilization, and lactic acid production during the fermentation process. The model was evaluated using experimental data from Tango and Ghaly (1999). The predicted results obtained from the model compared well with experimental (R{sup 2} = 0.92--0.98). The model was also used to investigate the effect of the initial substrate concentration on the lag period, fermentationmore » time, specific growth rate, and cell productivity during batch fermentation. The maximum specific growth rate ({micro}{sub m}), the saturation constant (K{sub S}), the substrate inhibition constant (K{sub IS}), and the lactic acid inhibition constant (K{sub IP}) were found to be 0.25h{sup {minus}1}, 0.9 g/L, 250.0 g/L, and 60.0 g/L, respectively. High initial lactose concentration in cheese whey reduced both the specific growth rate and substrate utilization rate due to the substrate inhibition phenomenon. The maximum lactic acid production occurred at about 100 g/L initial lactose concentration after 40 h of fermentation. The maximum lactic acid concentration above which Lactobacillus helveticus did not grow was found to be 80.0 g/L.« less

  18. Thermophilic Dry Methane Fermentation of Distillation Residue Eluted from Ethanol Fermentation of Kitchen Waste and Dynamics of Microbial Communities.

    PubMed

    Huang, Yu-Lian; Tan, Li; Wang, Ting-Ting; Sun, Zhao-Yong; Tang, Yue-Qin; Kida, Kenji

    2017-01-01

    Thermophilic dry methane fermentation is advantageous for feedstock with high solid content. Distillation residue with 65.1 % moisture content was eluted from ethanol fermentation of kitchen waste and subjected to thermophilic dry methane fermentation, after adjusting the moisture content to 75 %. The effect of carbon to nitrogen (C/N) ratio on thermophilic dry methane fermentation was investigated. Results showed that thermophilic dry methane fermentation could not be stably performed for >10 weeks at a C/N ratio of 12.6 and a volatile total solid (VTS) loading rate of 1 g/kg sludge/d; however, it was stably performed at a C/N ratio of 19.8 and a VTS loading rate of 3 g/kg sludge/d with 83.4 % energy recovery efficiency. Quantitative PCR analysis revealed that the number of bacteria and archaea decreased by two orders of magnitude at a C/N ratio of 12.6, whereas they were not influenced at a C/N ratio of 19.8. Microbial community analysis revealed that the relative abundance of protein-degrading bacteria increased and that of organic acid-oxidizing bacteria and acetic acid-oxidizing bacteria decreased at a C/N ratio of 12.6. Therefore, there was accumulation of NH 4 + and acetic acid, which inhibited thermophilic dry methane fermentation.

  19. Pilot scale fermentation of Jerusalem artichoke tuber pulp mashes

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ziobro, G.C.; Williams, L.A.

    1983-01-01

    Processing and fermentation of Jerusalem artichoke (Helianthus tuberosus L.) tuber pulp mashes were successfully carried out at pilot scales of 60 gallons and 1000 gallons. Whole tubers were pulped mechanically into a thick mash and fermented, using commercially available Saccharomyces cerevisiae and selected strains of Kluyveromyces fragilis. EtOH fermentation yields ranging from 50-70% of theoretical maximum were obtained in 3-4 days. Several problems regarding the processing and direct fermentation of tuber pulp mashes are discussed.

  20. Ultrasonic Monitoring of the Progress of Lactic Acid Fermentation

    NASA Astrophysics Data System (ADS)

    Masuzawa, Nobuyoshi; Kimura, Akihiro; Ohdaira, Etsuzo

    2003-05-01

    Promotion of lactic acid fermentation by ultrasonic irradiation has been attempted. It is possible to determine the progress of fermentation and production of a curd, i.e., yoghurt and or kefir, by measuring acidity using a pH meter. However, this method is inconvenient and indirect for the evaluation of the progress of lactic acid fermentation under anaerobic condition. In this study, an ultrasonic monitoring method for evaluating the progress of lactic acid fermentation was examined.

  1. Heat and Mass Transfer Measurements for Tray-Fermented Fungal Products

    NASA Astrophysics Data System (ADS)

    Jou, R.-Y.; Lo, C.-T.

    2011-01-01

    In this study, heat and mass transfer in static tray fermentation, which is widely used in solid-state fermentation (SSF) to produce fungal products, such as enzymes or koji, is investigated. Specifically, kinetic models of transport phenomena in the whole-tray chamber are emphasized. The effects of temperature, moisture, and humidity on microbial growth in large-scale static tray fermentation are essential to scale-up SSF and achieve uniform fermentation. In addition, heat and mass transfer of static tray fermentation of Trichoderma fungi with two tray setups—traditional linen coverings and stacks in a temperature-humidity chamber is examined. In both these setups, the following factors of fermentation were measured: air velocity, air temperature, illumination, pH, carbon dioxide (CO2) concentration, and substrate temperature, and the effects of bed height, moisture of substrate, and relative humidity of air are studied. A thin (1 cm) bed at 28 °C and 95 % relative humidity is found to be optimum. Furthermore, mixing was essential for achieving uniform fermentation of Trichoderma fungi. This study has important applications in large-scale static tray fermentation of fungi.

  2. Screening and optimization of some inorganic salts for the production of ergot alkaloids from Penicillium species using surface culture fermentation process.

    PubMed

    Shahid, Memuna Ghafoor; Nadeem, Muhammad; Baig, Shahjehan; Cheema, Tanzeem Akbar; Atta, Saira; Ghafoor, Gul Zareen

    2016-03-01

    The present study deals with the production of ergot alkaloids from Penicillium commune and Penicillium citrinum, using surface culture fermentation process. Impact of various inorganic salts was tested on the production of ergot alkaloids during the optimization studies of fermentation medium such as impact of various concentration levels of succinic acid, ammonium chloride, MgSO4, FeSO4, ZnSO4, pH and the effect of various incubation time periods was also determined on the production of ergot alkaloids from Penicillium commune and Penicillium citrinum. Highest yield of ergot alkaloids was obtained when Penicillium commune and Penicillium citrinum that were grown on optimum levels of ingredients such as 2 g succinic acid, 1.5 and 2 g NH4Cl, 1.5 g MgSO4, 1 g FeSO4, 1 and 1.5 g ZnSO4 after 21 days of incubation time period using pH 5 at 25(°)C incubation temperature in the fermentation medium. Ergot alkaloids were determined using Spectrophotometry and Thin Layer Chromatography (TLC) techniques.

  3. Impact of osmotic stress and ethanol inhibition in yeast cells on process oscillation associated with continuous very-high-gravity ethanol fermentation

    PubMed Central

    2013-01-01

    Background VHG fermentation is a promising process engineering strategy aiming at improving ethanol titer, and thus saving energy consumption for ethanol distillation and distillage treatment. However, sustained process oscillation was observed during continuous VHG ethanol fermentation, which significantly affected ethanol fermentation performance of the system. Results Sustained process oscillation was investigated in continuous VHG ethanol fermentation, and stresses exerted on yeast cells by osmotic pressure from unfermented sugars and ethanol inhibition developed within the fermentation system were postulated to be major factors triggering this phenomenon. In this article, steady state was established for continuous ethanol fermentation with LG medium containing 120 g/L glucose, and then 160 g/L non-fermentable xylose was supplemented into the LG medium to simulate the osmotic stress on yeast cells under the VHG fermentation condition, but the fermentation process was still at steady state, indicating that the impact of osmotic stress on yeast cells was not the main reason for the process oscillation. However, when 30 g/L ethanol was supplemented into the LG medium to simulate the ethanol inhibition in yeast cells under the VHG fermentation condition, process oscillation was triggered, which was augmented with extended oscillation period and exaggerated oscillation amplitude as ethanol supplementation was increased to 50 g/L, but the process oscillation was gradually attenuated when the ethanol supplementations were stopped, and the steady state was restored. Furthermore, gas stripping was incorporated into the continuous VHG fermentation system to in situ remove ethanol produced by Saccharomyces cerevisiae, and the process oscillation was also attenuated, but restored after the gas stripping was interrupted. Conclusions Experimental results indicated that ethanol inhibition rather than osmotic stress on yeast cells is one of the main factors triggering the

  4. Rye bran as fermentation matrix boosts in situ dextran production by Weissella confusa compared to wheat bran.

    PubMed

    Kajala, Ilkka; Mäkelä, Jari; Coda, Rossana; Shukla, Shraddha; Shi, Qiao; Maina, Ndegwa Henry; Juvonen, Riikka; Ekholm, Päivi; Goyal, Arun; Tenkanen, Maija; Katina, Kati

    2016-04-01

    The consumption of fiber-rich foods such as cereal bran is highly recommended due to its beneficial health effects. Pre-fermentation of bran with lactic acid bacteria can be used to improve the otherwise impaired flavor and textural qualities of bran-rich products. These positive effects are attributed to enzymatic modification of bran components and the production of functional metabolites like organic acids and exopolysaccharides such as dextrans. The aim of this study was to investigate dextran production in wheat and rye bran by fermentation with two Weissella confusa strains. Bran raw materials were analyzed for their chemical compositions and mineral content. Microbial growth and acidification kinetics were determined from the fermentations. Both strains produced more dextran in rye bran in which the fermentation-induced acidification was slower and the acidification lag phase longer than in wheat bran. Higher dextran production in rye bran is expected to be due to the longer period of optimal pH for dextran synthesis during fermentation. The starch content of wheat bran was higher, which may promote isomaltooligosaccharide formation at the expense of dextran production. W. confusa Cab3 produced slightly higher amounts of dextran than W. confusa VTT E-90392 in all raw materials. Fermentation with W. confusa Cab3 also resulted in lower residual fructose content which has technological relevance. The results indicate that wheat and particularly rye bran are promising matrices for producing technologically significant amounts of dextran, which facilitates the use of nutritionally valuable raw bran in food applications.

  5. Effect of fermentation and sterilization on anthocyanins in blueberry.

    PubMed

    Nie, Qixing; Feng, Lei; Hu, Jielun; Wang, Sunan; Chen, Haihong; Huang, Xiaojun; Nie, Shaoping; Xiong, Tao; Xie, Mingyong

    2017-03-01

    Blueberry products have various health benefits due to their high content of dietary anthocyanins. The aim of this study was to investigate the impact of fermentation and sterilization on total anthocyanin content, composition and some quality attributes of blueberry puree. The blueberry puree used here was fermented for 40 h at 37 °C by Lactobacillus after sterilization. The method of ultra-performance liquid chromatography-mass spectrometry was optimized for the rapid analysis of anthocyanins. Quality attributes including pH, color, total soluble solids and viscosity were measured. A total of 21 anthocyanins and five anthocyanidins were quantified by ultra-performance liquid chromatography. Fermented blueberry had reduced total anthocyanin content (29%) and levels of individual anthocyanins compared with fresh blueberry. Total anthocyanin content was decreased 46% by sterilization, and different degradation behavior of individual anthocyanin was appeared between fermented and sterilized-fermented blueberry puree. Fermentation and sterilization decreased the total soluble solids and pH and changed color parameters, while minimally influencing viscosity. The loss of total anthocyanin content by fermentation was related to the unstable structure of blueberry anthocyanins. Anthocyanins are sensitive to temperature (>80 °C), and degradation of anthocyanins by sterilization in blueberry should be considered in the fermentation procedure. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

  6. Investigation of the instability and low water kefir grain growth during an industrial water kefir fermentation process.

    PubMed

    Laureys, David; Van Jean, Amandine; Dumont, Jean; De Vuyst, Luc

    2017-04-01

    A poorly performing industrial water kefir production process consisting of a first fermentation process, a rest period at low temperature, and a second fermentation process was characterized to elucidate the causes of its low water kefir grain growth and instability. The frozen-stored water kefir grain inoculum was thawed and reactivated during three consecutive prefermentations before the water kefir production process was started. Freezing and thawing damaged the water kefir grains irreversibly, as their structure did not restore during the prefermentations nor the production process. The viable counts of the lactic acid bacteria and yeasts on the water kefir grains and in the liquors were as expected, whereas those of the acetic acid bacteria were high, due to the aerobic fermentation conditions. Nevertheless, the fermentations progressed slowly, which was caused by excessive substrate concentrations resulting in a high osmotic stress. Lactobacillus nagelii, Lactobacillus paracasei, Lactobacillus hilgardii, Leuconostoc mesenteroides, Bifidobacterium aquikefiri, Gluconobacter roseus/oxydans, Gluconobacter cerinus, Saccharomyces cerevisiae, and Zygotorulaspora florentina were the most prevalent microorganisms. Lb. hilgardii, the microorganism thought to be responsible for water kefir grain growth, was not found culture-dependently, which could explain the low water kefir grain growth of this industrial process.

  7. Exogenous acetaldehyde as a tool for modulating wine color and astringency during fermentation.

    PubMed

    Sheridan, Marlena K; Elias, Ryan J

    2015-06-15

    Wine tannins undergo modifications during fermentation and storage that can decrease their perceived astringency and increase color stability. Acetaldehyde acts as a bridging compound to form modified tannins and polymeric pigments that are less likely to form tannin-protein complexes than unmodified tannins. Red wines are often treated with oxygen in order to yield acetaldehyde, however this approach can lead to unintended consequences due to the generation of reactive oxygen species. The present study employs exogenous acetaldehyde at relatively low and high treatment concentrations during fermentation to encourage tannin modification without promoting potentially deleterious oxidation reactions. The high acetaldehyde treatment significantly increased polymeric pigments in the wine without increasing concentrations of free and sulfite-bound acetaldehyde. Protein-tannin precipitation was also significantly decreased with the addition of exogenous acetaldehyde. These results indicate a possible treatment of wines early in their production to increase color stability and lower astringency of finished wines. Copyright © 2015 Elsevier Ltd. All rights reserved.

  8. Predicting the concentration of verotoxin-producing Escherichia coli bacteria during processing and storage of fermented raw-meat sausages.

    PubMed

    Quinto, E J; Arinder, P; Axelsson, L; Heir, E; Holck, A; Lindqvist, R; Lindblad, M; Andreou, P; Lauzon, H L; Marteinsson, V Þ; Pin, C

    2014-05-01

    A model to predict the population density of verotoxigenic Escherichia coli (VTEC) throughout the elaboration and storage of fermented raw-meat sausages (FRMS) was developed. Probabilistic and kinetic measurement data sets collected from publicly available resources were completed with new measurements when required and used to quantify the dependence of VTEC growth and inactivation on the temperature, pH, water activity (aw), and concentration of lactic acid. Predictions were compared with observations in VTEC-contaminated FRMS manufactured in a pilot plant. Slight differences in the reduction of VTEC were predicted according to the fermentation temperature, 24 or 34°C, with greater inactivation at the highest temperature. The greatest reduction was observed during storage at high temperatures. A population decrease greater than 6 decimal logarithmic units was observed after 66 days of storage at 25°C, while a reduction of only ca. 1 logarithmic unit was detected at 12°C. The performance of our model and other modeling approaches was evaluated throughout the processing of dry and semidry FRMS. The greatest inactivation of VTEC was predicted in dry FRMS with long drying periods, while the smallest reduction was predicted in semidry FMRS with short drying periods. The model is implemented in a computing tool, E. coli SafeFerment (EcSF), freely available from http://www.ifr.ac.uk/safety/EcoliSafeFerment. EcSF integrates growth, probability of growth, and thermal and nonthermal inactivation models to predict the VTEC concentration throughout FRMS manufacturing and storage under constant or fluctuating environmental conditions.

  9. Predicting the Concentration of Verotoxin-Producing Escherichia coli Bacteria during Processing and Storage of Fermented Raw-Meat Sausages

    PubMed Central

    Quinto, E. J.; Arinder, P.; Axelsson, L.; Heir, E.; Holck, A.; Lindqvist, R.; Lindblad, M.; Andreou, P.; Lauzon, H. L.; Marteinsson, V. Þ.

    2014-01-01

    A model to predict the population density of verotoxigenic Escherichia coli (VTEC) throughout the elaboration and storage of fermented raw-meat sausages (FRMS) was developed. Probabilistic and kinetic measurement data sets collected from publicly available resources were completed with new measurements when required and used to quantify the dependence of VTEC growth and inactivation on the temperature, pH, water activity (aw), and concentration of lactic acid. Predictions were compared with observations in VTEC-contaminated FRMS manufactured in a pilot plant. Slight differences in the reduction of VTEC were predicted according to the fermentation temperature, 24 or 34°C, with greater inactivation at the highest temperature. The greatest reduction was observed during storage at high temperatures. A population decrease greater than 6 decimal logarithmic units was observed after 66 days of storage at 25°C, while a reduction of only ca. 1 logarithmic unit was detected at 12°C. The performance of our model and other modeling approaches was evaluated throughout the processing of dry and semidry FRMS. The greatest inactivation of VTEC was predicted in dry FRMS with long drying periods, while the smallest reduction was predicted in semidry FMRS with short drying periods. The model is implemented in a computing tool, E. coli SafeFerment (EcSF), freely available from http://www.ifr.ac.uk/safety/EcoliSafeFerment. EcSF integrates growth, probability of growth, and thermal and nonthermal inactivation models to predict the VTEC concentration throughout FRMS manufacturing and storage under constant or fluctuating environmental conditions. PMID:24561587

  10. Effects of dry period length and dietary energy source on metabolic status and hepatic gene expression of dairy cows in early lactation.

    PubMed

    Chen, J; Gross, J J; van Dorland, H A; Remmelink, G J; Bruckmaier, R M; Kemp, B; van Knegsel, A T M

    2015-02-01

    In a prior study, we observed that cows with a 0-d dry period had greater energy balance and lower milk production compared with cows with a 30- or 60-d dry period in early lactation. The objective of the current study was to evaluate the influence of dry period length on metabolic status and hepatic gene expression in cows fed a lipogenic or glucogenic diet in early lactation. Holstein-Friesian dairy cows (n=167) were assigned randomly to 3×2 factorial design with 3 dry period lengths (n=56, 55, and 56 for 0-, 30-, and 60-d dry, respectively) and 2 early lactation diets (n=84 and 83 for glucogenic and lipogenic diet, respectively). Cows were fed a glucogenic or lipogenic diet from 10d before the expected calving date and onward. The main ingredient for a glucogenic concentrate was corn, and the main ingredients for a lipogenic concentrate were sugar beet pulp, palm kernel, and rumen-protected palm oil. Blood was sampled weekly from 95 cows from wk 3 precalving to wk 8 postcalving. Liver samples were collected from 76 cows in wk -2, 2, and 4 relative to calving. Liver samples were analyzed for triacylglycerol concentrations and mRNA expression of 12 candidate genes. Precalving, cows with a 0-d dry period had greater plasma β-hydroxybutyrate, urea, and insulin concentrations compared with cows with a 30- or 60-d dry period. Postcalving, cows with a 0-d dry period had lower liver triacylglycerol and plasma nonesterified fatty acids concentrations (0.20, 0.32, and 0.36mmol/L for 0-, 30-, and 60-d dry period, respectively), greater plasma glucose, insulin-like growth factor-I, and insulin (24.38, 14.02, and 11.08µIU/mL for 0-, 30-, and 60-d dry period, respectively) concentrations, and lower hepatic mRNA expression of pyruvate carboxylase, compared with cows with a 30- or 60-d dry period. Plasma urea and β-hydroxybutyrate concentrations were greater in cows fed a lipogenic diet compared with cows fed a glucogenic diet. In conclusion, cows with a 0-d dry period had

  11. A novel non-dairy beverage from durian pulp fermented with selected probiotics and yeast.

    PubMed

    Lu, Yuyun; Putra, Satya Dwi; Liu, Shao-Quan

    2018-01-16

    This study investigated the effects of sequential inoculation (Seq-I) of Bifidobacterium animalis subsp. lactis or Lactobacillus casei with yeast Williopsis saturnus on durian pulp fermentation. Seq-I of W. saturnus following B. animalis subsp. lactis did not bring about any significant differences compared to the B. animalis subsp. lactis monoculture due to the sharp early death of W. saturnus soon after inoculation. However, Seq-I of W. saturnus significantly enhanced the survival of L. casei and improved the utilization of fructose and glucose compared to L. casei monoculture. In addition, there were significant differences in the metabolism of organic acids especially for lactic acid and succinic acid. Furthermore, Seq-I produced significantly higher levels of volatile compounds including alcohols (ethanol and 2-phenylethyl alcohol) and acetate esters (2-phenylethyl acetate, isoamyl acetate and ethyl acetate), which would positively contribute to the flavour notes. Although the initial volatile sulphur compounds were reduced to trace levels after fermentation, but the durian odour still remained. This study suggests that the use of probiotics and W. saturnus to ferment durian pulp could act as a potential avenue to develop a novel non-dairy durian-based functional beverage to deliver probiotics. Copyright © 2017 Elsevier B.V. All rights reserved.

  12. Fermentation of polysaccharides by Klebsiella and other facultative bacilli

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ochuba, G.U.; Von Riesen, V.L.

    1980-05-01

    Fermentations of 10 polysaccharides by species of the family Enterobacteriaceae were examined. Algin, guar, karaya, xanthan, and xylan were not fermented by any of the strains tested. Most of the activity was found in the tribe Klebsielleae. Klebseilla oxytoca fermented amylopectin (97% of the strains studied), carrageenan (100%), inulin (68%), polypectate (100%), and tragacanth (100%). Klebsiella pneumoniae fermented amylopectin (91%), carrageenan (100%), and tragacanth (86%). Carraggeenan was also fermented by Enterobacter aerogenes (100%), Enterobacter agglomerans (63%), Enterobacter cloacae (95%), and pectobacterium (38%). pectobacterium shared polypectate fermentation (100%) with K. oxytoca. With one exception, Serratia strains were negative on all polysaccharides.more » These results, along with other evidence, indicate that (i) the genus Klebsiella is biochemically the most versatile genus of the tribe, (ii) because of its distinct characteristics, K. oxytoca warrants species designation separate from K. pneumoniae, and (iii) some food additives generally considered indigestible can be metabolized by a few species of facultative bacilli, whereas others appear to be resistant.« less

  13. Review - Lactic acid bacteria in traditional fermented Asian foods.

    PubMed

    Azam, Mariya; Mohsin, Mashkoor; Ijaz, Hira; Tulain, Ume Ruqia; Ashraf, Muhammad Adnan; Fayyaz, Ahad; Abadeen, Zainul; Kamran, Qindeel

    2017-09-01

    Lactic acid bacteria play vital roles in various fermented foods in Asia. This paper reviews many types of the world's lactic acid fermented foods and discusses the beneficial effects of lactic acid fermentation of food. The lactic acid bacteria associated with foods now include species of the genera Carnobacterium, Enterococcus, Lactobacillus, Lactococcus, Leuconostoc, Oenococcus, Pediococcus, Streptococcus, Tetragenococcus, Vagococcus and Weissella. Lactic acid bacteria (LAB) are involved in many fermentation processes of Asian traditional foods, demonstrating their profound effects on improving food quality and food safety. During the past few decades' interest has arisen in the use of the varied antagonistic activities of LAB to extent the shelf-life of protein-rich products such as meats and fish. This review article outlines the main types of LAB fermentation as well as their typical fermented foods such as idli, kishk, sauerkraut, koumiss, Suan-tsai, stinky tofu, Chinese sausage and kefir. The roles of LAB and the reasons for their common presence are also discussed.

  14. Survival of commercial yeasts in the winery environment and their prevalence during spontaneous fermentations.

    PubMed

    Blanco, P; Orriols, I; Losada, A

    2011-01-01

    Inoculation of active dry yeasts during the wine-making process has become a common practice in most wine-producing regions; this practice may affect the diversity of the indigenous population of Saccharomyces cerevisiae in the winery. The aim of this work was to study the incidence of commercial yeasts in the experimental winery of Estación de Viticultura e Enoloxía de Galicia (EVEGA) and their ability to lead spontaneous fermentations. To do this, 64 spontaneous fermentations were carried out in the experimental cellar of EVEGA over a period of 7 years. Samples were taken from must and at the beginning, vigorous and final stages of fermentation. A representative number of yeast colonies was isolated from each sample. S. cerevisiae strains were characterised by analysis of mitochondrial DNA restriction patterns. The results showed that although more than 40 different strains of S. cerevisiae were identified, only 10 were found as the dominant strain or in codominance with other strains in spontaneous fermentations. The genetic profiles (mtDNA-RFLPs) of eight of these strains were similar to those of different commercial yeasts that had been previously used in the EVEGA cellar. The remaining two strains were autochthonous ones that were able to reach implantation frequencies as high of those of commercial yeasts. These results clearly indicated that commercial wine yeasts were perfectly adapted to survive in EVEGA cellar conditions, and they successfully competed with the indigenous strains of S. cerevisiae, even during spontaneous fermentations. On the other hand, autochthonous dominant strains that presented desirable oenological traits could be of interest to preserve wine typicity.

  15. Mathematical models of ABE fermentation: review and analysis.

    PubMed

    Mayank, Rahul; Ranjan, Amrita; Moholkar, Vijayanand S

    2013-12-01

    Among different liquid biofuels that have emerged in the recent past, biobutanol produced via fermentation processes is of special interest due to very similar properties to that of gasoline. For an effective design, scale-up, and optimization of the acetone-butanol-ethanol (ABE) fermentation process, it is necessary to have insight into the micro- and macro-mechanisms of the process. The mathematical models for ABE fermentation are efficient tools for this purpose, which have evolved from simple stoichiometric fermentation equations in the 1980s to the recent sophisticated and elaborate kinetic models based on metabolic pathways. In this article, we have reviewed the literature published in the area of mathematical modeling of the ABE fermentation. We have tried to present an analysis of these models in terms of their potency in describing the overall physiology of the process, design features, mode of operation along with comparison and validation with experimental results. In addition, we have also highlighted important facets of these models such as metabolic pathways, basic kinetics of different metabolites, biomass growth, inhibition modeling and other additional features such as cell retention and immobilized cultures. Our review also covers the mathematical modeling of the downstream processing of ABE fermentation, i.e. recovery and purification of solvents through flash distillation, liquid-liquid extraction, and pervaporation. We believe that this review will be a useful source of information and analysis on mathematical models for ABE fermentation for both the appropriate scientific and engineering communities.

  16. Paraformaldehyde-Resistant Starch-Fermenting Bacteria in “Starch-Base” Drilling Mud

    PubMed Central

    Myers, G. E.

    1962-01-01

    Starch-fermenting bacteria were found in each of 12 samples of nonfermenting starch-base drilling mud examined. Of the 12 samples, 3 contained very active starch-fermenting gram-positive spore-bearing bacilli closely resembling Bacillus subtilis. Similar active starch-fermenting bacteria were found in fermenting starch-base drilling mud and in corn starch and slough water used to prepare such mud. The active starch-fermenting microorganisms completely hydrolyzed 1% (w/v) corn starch within 24 hr at 37.5 C. The active starch-fermenting bacteria isolated from fermenting drilling mud were capable of surviving 12 hr of continuous exposure to 0.1% (w/w) paraformaldehyde or 1 hr of continuous exposure to 0.5% (w/w) paraformaldehyde, with no diminution in starch-fermenting ability. The same organisms fermented starch after 3 hr of continuous exposure to 0.5% (w/w) paraformaldehyde, but not after 4 hr of exposure. The phenomenon of rapid disappearance of paraformaldehyde from fermenting drilling mud was observed in the laboratory using a modified sodium sulfite test. Paraformaldehyde, initially present in a concentration of 0.192 lb per barrel of mud, completely disappeared in 9 hr at 22 to 23 C. A significant decrease in paraformaldehyde concentration was detected 0.5 hr after preparation of the mud. It is suggested that the presence of relatively high concentrations of ammonia and chloride in the mud may facilitate the disappearance of paraformaldehyde. The failure of 0.1% (w/w) paraformaldehyde to inhibit the strong starch-fermenting microorganisms isolated from fermenting drilling mud, and the rapid disappearance of paraformaldehyde from the mud, explains the fermentation of starch which occurred in this mud, despite the addition of paraformaldehyde. PMID:13936949

  17. Treponemal disease in the middle Archaic to early Woodland periods of the western Tennessee River Valley.

    PubMed

    Smith, Maria Ostendorf

    2006-10-01

    The high frequency of late prehistoric New World treponemal disease is attributable to the demographic changes concomitant with the adoption of agriculture. However, these demographic changes in group mobility and site density episodically preceded intensive plant domestication, suggesting possible staggered temporal change in observed treponemal disease case frequency. Thirteen convincing and an additional two probable (N = 581) cases of treponemal disease were identified in an eight-site skeletal sample spanning the Middle (6,000-3,000 BCE) to Late (2,500-ca. 1,000 to 500 BCE) Archaic and Early Woodland (500 BCE-0 CE) periods from the western Tennessee River Valley. Treponemal disease cases are infrequent in both the Middle (3/115, 2.6%) and Late (2 to 4 cases, Early Woodland horizon. As the subsistence economy across the Archaic-Woodland temporal boundary in the western Tennessee River Valley remained, as elsewhere, based on intensive hunting and collecting, the demographic corollaries of treponemal disease would apparently not be met. However, the traditional horizon marker of the Woodland period is the adoption of pottery, an activity associated with sedentism.

  18. Kinetic Study of Acetone-Butanol-Ethanol Fermentation in Continuous Culture

    PubMed Central

    Buehler, Edward A.; Mesbah, Ali

    2016-01-01

    Acetone-butanol-ethanol (ABE) fermentation by clostridia has shown promise for industrial-scale production of biobutanol. However, the continuous ABE fermentation suffers from low product yield, titer, and productivity. Systems analysis of the continuous ABE fermentation will offer insights into its metabolic pathway as well as into optimal fermentation design and operation. For the ABE fermentation in continuous Clostridium acetobutylicum culture, this paper presents a kinetic model that includes the effects of key metabolic intermediates and enzymes as well as culture pH, product inhibition, and glucose inhibition. The kinetic model is used for elucidating the behavior of the ABE fermentation under the conditions that are most relevant to continuous cultures. To this end, dynamic sensitivity analysis is performed to systematically investigate the effects of culture conditions, reaction kinetics, and enzymes on the dynamics of the ABE production pathway. The analysis provides guidance for future metabolic engineering and fermentation optimization studies. PMID:27486663

  19. Simulation and optimization of continuous extractive fermentation with recycle system

    NASA Astrophysics Data System (ADS)

    Widjaja, Tri; Altway, Ali; Rofiqah, Umi; Airlangga, Bramantyo

    2017-05-01

    Extractive fermentation is continuous fermentation method which is believed to be able to substitute conventional fermentation method (batch). The recovery system and ethanol refinery will be easier. Continuous process of fermentation will make the productivity increase although the unconverted sugar in continuous fermentation is still in high concentration. In order to make this process more efficient, the recycle process was used. Increasing recycle flow will enhance the probability of sugar to be re-fermented. However, this will make ethanol enter fermentation column. As a result, the accumulated ethanol will inhibit the growth of microorganism. This research aims to find optimum conditions of solvent to broth ratio (S:B) and recycle flow to fresh feed ratio in order to produce the best yield and productivity. This study employed optimization by Hooke Jeeves method using Matlab 7.8 software. The result indicated that optimum condition occured in S: B=2.615 and R: F=1.495 with yield = 50.2439 %.

  20. Wastewater recycling technology for fermentation in polyunsaturated fatty acid production.

    PubMed

    Song, Xiaojin; Ma, Zengxin; Tan, Yanzhen; Zhang, Huidan; Cui, Qiu

    2017-07-01

    To reduce fermentation-associated wastewater discharge and the cost of wastewater treatment, which further reduces the total cost of DHA and ARA production, this study first analyzed the composition of wastewater from Aurantiochytrium (DHA) and Mortierella alpina (ARA) fermentation, after which wastewater recycling technology for these fermentation processes was developed. No negative effects of DHA and ARA production were observed when the two fermentation wastewater methods were cross-recycled. DHA and ARA yields were significantly inhibited when the wastewater from the fermentation process was directly reused. In 5-L fed-batch fermentation experiments, using this cross-recycle technology, the DHA and ARA yields were 30.4 and 5.13gL -1 , respectively, with no significant changes (P>0.05) compared to the control group, and the water consumption was reduced by half compared to the traditional process. Therefore, this technology has great potential in industrial fermentation for polyunsaturated fatty acid production. Copyright © 2017 Elsevier Ltd. All rights reserved.

  1. Enhancing ethanol yields through d-xylose and l-arabinose co-fermentation after construction of a novel high efficient l-arabinose-fermenting Saccharomyces cerevisiae strain.

    PubMed

    Caballero, Antonio; Ramos, Juan Luis

    2017-04-01

    Lignocellulose contains two pentose sugars, l-arabinose and d-xylose, neither of which is naturally fermented by first generation (1G) ethanol-producing Saccharomyces cerevisiae yeast. Since these sugars are inaccessible to 1G yeast, a significant percentage of the total carbon in bioethanol production from plant residues, which are used in second generation (2G) ethanol production, remains unused. Recombinant Saccharomyces cerevisiae strains capable of fermenting d-xylose are available on the market; however, there are few examples of l-arabinose-fermenting yeasts, and commercially, there are no strains capable of fermenting both d-xylose and l-arabinose because of metabolic incompatibilities when both metabolic pathways are expressed in the same cell. To attempt to solve this problem we have tested d-xylose and l-arabinose co-fermentation. To find efficient alternative l-arabinose utilization pathways to the few existing ones, we have used stringent methodology to screen for new genes (metabolic and transporter functions) to facilitate l-arabinose fermentation in recombinant yeast. We demonstrate the feasibility of this approach in a successfully constructed yeast strain capable of using l-arabinose as the sole carbon source and capable of fully transforming it to ethanol, reaching the maximum theoretical fermentation yield (0.43 g g-1). We demonstrate that efficient co-fermentation of d-xylose and l-arabinose is feasible using two different co-cultured strains, and observed no fermentation delays, yield drops or accumulation of undesired byproducts. In this study we have identified a technically efficient strategy to enhance ethanol yields by 10 % in 2G plants in a process based on C5 sugar co-fermentation.

  2. Inhibitory activity of cheese whey fermented with kefir grains.

    PubMed

    Londero, A; Quinta, R; Abraham, A G; Sereno, R; De Antoni, G; Garrote, G L

    2011-01-01

    We investigated the chemical and microbiological compositions of three types of whey to be used for kefir fermentation as well as the inhibitory capacity of their subsequent fermentation products against 100 Salmonella sp. and 100 Escherichia coli pathogenic isolates. All the wheys after fermentation with 10% (wt/vol) kefir grains showed inhibition against all 200 isolates. The content of lactic acid bacteria in fermented whey ranged from 1.04 × 10(7) to 1.17 × 10(7) CFU/ml and the level of yeasts from 2.05 × 10(6) to 4.23 × 10(6) CFU/ml. The main changes in the chemical composition during fermentation were a decrease in lactose content by 41 to 48% along with a corresponding lactic acid production to a final level of 0.84 to 1.20% of the total reaction products. The MIC was a 30% dilution of the fermentation products for most of the isolates, while the MBC varied between 40 and 70%, depending on the isolate. The pathogenic isolates Salmonella enterica serovar Enteritidis 2713 and E. coli 2710 in the fermented whey lost their viability after 2 to 7 h of incubation. When pathogens were deliberately inoculated into whey before fermentation, the CFU were reduced by 2 log cycles for E. coli and 4 log cycles for Salmonella sp. after 24 h of incubation. The inhibition was mainly related to lactic acid production. This work demonstrated the possibility of using kefir grains to ferment an industrial by-product in order to obtain a natural acidic preparation with strong bacterial inhibitory properties that also contains potentially probiotic microorganisms.

  3. Lactic acid fermentation and storage of blanched garlic.

    PubMed

    de Castro, A; Montaño, A; Sánchez, A H; Rejano, L

    1998-02-17

    The controlled fermentation of peeled, blanched garlic, using a starter culture of Lactobacillus plantarum, was studied and compared with that of unblanched garlic. Blanching was carried out in hot water (90 degrees C) for 15 min. The starter grew abundantly in the case of blanched garlic, producing mainly lactic acid and reaching a pH of 3.8 after 7 days, but its growth was inhibited in unblanched garlic. Ethanol and fructose, coming from enzymatic activities of the garlic, and a green pigment were formed during the fermentation of unblanched garlic, but not of blanched garlic. The blanched garlic fermented by L. plantarum, even without a preservation treatment (pasteurization), was microbiologically stable during storage at 30 degrees C in an acidified brine (approximately 3% (w/w) NaCl and pH 3.5 at equilibrium), but fructans were hydrolyzed. The packed fermented product and that obtained by direct packing without fermentation were not significantly different with regard to flavour.

  4. Establishing the relative importance of damaged starch and fructan as sources of fermentable sugars in wheat flour and whole meal bread dough fermentations.

    PubMed

    Struyf, Nore; Laurent, Jitka; Lefevere, Bianca; Verspreet, Joran; Verstrepen, Kevin J; Courtin, Christophe M

    2017-03-01

    It is generally believed that maltose drives yeast-mediated bread dough fermentation. The relative importance of fructose and glucose, released from wheat fructan and sucrose by invertase, compared to maltose is, however, not documented. This is surprising given the preference of yeast for glucose and fructose over maltose. This study revealed that, after 2h fermentation of wheat flour dough, about 44% of the sugars consumed were generated by invertase-mediated degradation of fructan, raffinose and sucrose. The other 56% were generated by amylases. In whole meal dough, 70% of the sugars consumed were released by invertase activity. Invertase-mediated sugar release seems to be crucial during the first hour of fermentation, while amylase-mediated sugar release was predominant in the later stages of fermentation, which explains why higher amylolytic activity prolonged the productive fermentation time only. These results illustrate the importance of wheat fructan and sucrose content and their degradation for dough fermentations. Copyright © 2016 Elsevier Ltd. All rights reserved.

  5. Carbohydrate utilization and the lager yeast transcriptome during brewery fermentation.

    PubMed

    Gibson, Brian R; Boulton, Chris A; Box, Wendy G; Graham, Neil S; Lawrence, Stephen J; Linforth, Robert S T; Smart, Katherine A

    2008-08-01

    The fermentable carbohydrate composition of wort and the manner in which it is utilized by yeast during brewery fermentation have a direct influence on fermentation efficiency and quality of the final product. In this study the response of a brewing yeast strain to changes in wort fermentable carbohydrate concentration and composition during full-scale (3275 hl) brewery fermentation was investigated by measuring transcriptome changes with the aid of oligonucleotide-based DNA arrays. Up to 74% of the detectable genes showed a significant (pfermentation and the majority of these genes showed transient or prolonged peaks in expression following the exhaustion of the monosaccharides from the wort. Transcriptional activity of many genes was consistent with their known responses to glucose de/repression under laboratory conditions, despite the presence of di- and trisaccharide sugars in the wort. In a number of cases the transcriptional response of genes was not consistent with their known responses to glucose, suggesting a degree of complexity during brewery fermentation which cannot be replicated in small-scale wort fermentations or in laboratory experiments involving defined media. Copyright 2008 John Wiley & Sons, Ltd.

  6. Prokaryotic community composition in alkaline-fermented skate (Raja pulchra).

    PubMed

    Jang, Gwang Il; Kim, Gahee; Hwang, Chung Yeon; Cho, Byung Cheol

    2017-02-01

    Prokaryotes were extracted from skates and fermented skates purchased from fish markets and a local manufacturer in South Korea. The prokaryotic community composition of skates and fermented skates was investigated using 16S rRNA pyrosequencing. The ranges for pH and salinity of the grinded tissue extract from fermented skates were 8.4-8.9 and 1.6-6.6%, respectively. Urea and ammonia concentrations were markedly low and high, respectively, in fermented skates compared to skates. Species richness was increased in fermented skates compared to skates. Dominant and predominant bacterial groups present in the fermented skates belonged to the phylum Firmicutes, whereas those in skates belonged to Gammaproteobacteria. The major taxa found in Firmicutes were Atopostipes (Carnobacteriaceae, Lactobacillales) and/or Tissierella (Tissierellaceae, Tissierellales). A combination of RT-PCR and pyrosequencing for active bacterial composition showed that the dominant taxa i.e., Atopostipes and Tissierella, were active in fermented skate. Those dominant taxa are possibly marine lactic acid bacteria. Marine bacteria of the taxa Lactobacillales and/or Clostridia seem to be important in alkaline fermentation of skates. Copyright © 2016 Elsevier Ltd. All rights reserved.

  7. Oxygen and diverse nutrients influence the water kefir fermentation process.

    PubMed

    Laureys, David; Aerts, Maarten; Vandamme, Peter; De Vuyst, Luc

    2018-08-01

    Eight water kefir fermentation series differing in the presence of oxygen, the nutrient concentration, and the nutrient source were studied during eight consecutive backslopping steps. The presence of oxygen allowed the proliferation of acetic acid bacteria, resulting in high concentrations of acetic acid, and decreased the relative abundance of Bifidobacterium aquikefiri. Low nutrient concentrations resulted in slow water kefir fermentation and high pH values, which allowed the growth of Comamonas testosteroni/thiooxydans. Further, low nutrient concentrations favored the growth of Lactobacillus hilgardii and Dekkera bruxellensis, whereas high nutrient concentrations favored the growth of Lactobacillus nagelii and Saccharomyces cerevisiae. Dried figs, dried apricots, and raisins resulted in stable water kefir fermentation. Water kefir fermentation with dried apricots resulted in the highest pH and water kefir grain growth, whereas that with raisins resulted in the lowest pH and water kefir grain growth. Further, water kefir fermentation with raisins resembled fermentations with low nutrient concentrations, that with dried apricots resembled fermentations with normal nutrient concentrations, and that with fresh figs or a mixture of yeast extract and peptone resembled fermentations with high nutrient concentrations. Copyright © 2018 Elsevier Ltd. All rights reserved.

  8. Manufacturing Ethyl Acetate From Fermentation Ethanol

    NASA Technical Reports Server (NTRS)

    Rohatgi, Naresh K.; Ingham, John D.

    1991-01-01

    Conceptual process uses dilute product of fermentation instead of concentrated ethanol. Low-concentration ethanol, extracted by vacuum from fermentation tank, and acetic acid constitutes feedstock for catalytic reaction. Product of reaction goes through steps that increases ethyl acetate content to 93 percent by weight. To conserve energy, heat exchangers recycle waste heat to preheat process streams at various points.

  9. Influence of nitrogen sources on growth and fermentation performance of different wine yeast species during alcoholic fermentation.

    PubMed

    Kemsawasd, Varongsiri; Viana, Tiago; Ardö, Ylva; Arneborg, Nils

    2015-12-01

    In this study, the influence of twenty different single (i.e. 19 amino acids and ammonium sulphate) and two multiple nitrogen sources (N-sources) on growth and fermentation (i.e. glucose consumption and ethanol production) performance of Saccharomyces cerevisiae and of four wine-related non-Saccharomyces yeast species (Lachancea thermotolerans, Metschnikowia pulcherrima, Hanseniaspora uvarum and Torulaspora delbrueckii) was investigated during alcoholic fermentation. Briefly, the N-sources with beneficial effects on all performance parameters (or for the majority of them) for each yeast species were alanine, arginine, asparagine, aspartic acid, glutamine, isoleucine, ammonium sulphate, serine, valine and mixtures of 19 amino acids and of 19 amino acids plus ammonium sulphate (for S. cerevisiae), serine (for L. thermotolerans), alanine (for H. uvarum), alanine and asparagine (for M. pulcherrima), arginine, asparagine, glutamine, isoleucine and mixture of 19 amino acids (for T. delbrueckii). Furthermore, our results showed a clear positive effect of complex mixtures of N-sources on S. cerevisiae and on T. delbrueckii (although to a lesser extent) as to all performance parameters studied, whereas for L. thermotolerans, H. uvarum and M. pulcherrima, single amino acids affected growth and fermentation performance to the same extent as the mixtures. Moreover, we found groups of N-sources with similar effects on the growth and/or fermentation performance of two or more yeast species. Finally, the influences of N-sources observed for T. delbrueckii and H. uvarum resembled those of S. cerevisiae the most and the least, respectively. Overall, this work contributes to an improved understanding of how different N-sources affect growth, glucose consumption and ethanol production of wine-related yeast species under oxygen-limited conditions, which, in turn, may be used to, e.g. optimize growth and fermentation performance of the given yeast upon N-source supplementation during

  10. Treatment of biomass to obtain fermentable sugars

    DOEpatents

    Dunson, Jr., James B.; Tucker, Melvin [Lakewood, CO; Elander, Richard [Evergreen, CO; Hennessey, Susan M [Avondale, PA

    2011-04-26

    Biomass is pretreated using a low concentration of aqueous ammonia at high biomass concentration. Pretreated biomass is further hydrolyzed with a saccharification enzyme consortium. Fermentable sugars released by saccharification may be utilized for the production of target chemicals by fermentation.

  11. Investigation of food waste valorization through sequential lactic acid fermentative production and anaerobic digestion of fermentation residues.

    PubMed

    Demichelis, Francesca; Pleissner, Daniel; Fiore, Silvia; Mariano, Silvia; Navarro Gutiérrez, Ivette Michelle; Schneider, Roland; Venus, Joachim

    2017-10-01

    This work concerns the investigation of the sequential production of lactic acid (LA) and biogas from food waste (FW). LA was produced from FW using a Streptococcus sp. strain via simultaneous saccharification and fermentation (SSF) and separate enzymatic hydrolysis and fermentation (SHF). Via SHF a yield of 0.33g LA /g FW (productivity 3.38g LA /L·h) and via SSF 0.29g LA /g FW (productivity 2.08g LA /L·h) was obtained. Fermentation residues and FW underwent anaerobic digestion (3wt% TS). Biogas yields were 0.71, 0.74 and 0.90Nm 3 /kg VS for FW and residues from SSF and SHF respectively. The innovation of the approach is considering the conversion of FW into two different products through a biorefinery concept, therefore making economically feasible LA production and valorising its fermentative residues. Finally, a mass balance of three different outlines with the aim to assess the amount of LA and biogas that may be generated within different scenarios is presented. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. Fermented pigeon pea (Cajanus cajan) ingredients in pasta products.

    PubMed

    Torres, Alexia; Frias, J; Granito, M; Vidal-Valverde, C

    2006-09-06

    Pigeon pea (Cajanus cajan var. aroíto) seeds were fermented in order to remove antinutritional factors and to obtain functional legume flour to be used as pasta ingredients. Fermentation brought about a drastic reduction of alpha-galactosides (82%), phytic acid (48%), and trypsin inhibitor activity (39%). Fermented legume flours presented a notable increase of fat and total soluble available carbohydrates, a slight decrease of protein, dietary fiber, calcium, vitamin B2, vitamin E, and total antioxidant capacity, and a decrease of soluble dietary fiber, Na, K, Mg, and Zn contents. No changes were observed in the level of starch and tannins as a consequence of fermentation. The fermented flour was used as an ingredient to make pasta products in a proportion of 5, 10, and 12%. The supplemented pasta products obtained had longer cooking times, higher cooking water absorptions, higher cooking loss, and higher protein loss in water than control pasta (100% semolina). From sensory evaluations, fortified pasta with 5 and 10% fermented pigeon pea flour had an acceptability score similar to control pasta. Pasta supplemented with 10% fermented pigeon pea flour presented higher levels of protein, fat, dietary fiber, mineral, vitamin E, and Trolox equivalent antioxidant capacity than 100% semolina pasta and similar vitamins B1 and B2 contents. Protein efficiency ratios and true protein digestibility improved (73 and 6%, respectively) after supplementation with 10% fermented pigeon pea flour; therefore, the nutritional value was enhanced.

  13. Purification and fermentation characteristics of exopolysaccharide from Fomitopsis castaneus Imaz.

    PubMed

    Guo, Wenkui; Chi, Yujie

    2017-12-01

    Short-chain fatty acids (SCFAs), which are the end products of carbohydrate fermentation in the gut, mainly contribute to energy metabolism in mammals. The amount of SCFAs produced during fermentation is an important parameter that characterizes the fermentation capacity of a system. This paper reports on the fermentation characteristics of exopolysaccharides (EPS) isolated from Fomitopsis castaneus Imaz, a wood-rot fungal species. We isolated and purified the main EPS fraction by freeze drying and DEAE-Sepharose fast flow chromatography. We then analyzed the monosaccharide composition of EPS. The isolated EPS was mainly composed of glucose, galactose, rhamnose, mannose, and arabinose. The characteristic absorption peaks of sugar esters were also detected. Fresh fecal extracts from healthy adults and children were used as fermentation substrate to simulate the human intestinal environment (anaerobic conditions at 37°C) and study the fermentation characteristics of the purified EPS. Adding the isolated EPS to the fermentation system of the simulated intestinal environment increased the SCFAs content in the fecal extract of adults and children. However, the yield of SCFAs, particularly butyric acid, in the fermentation system of fecal extract in children was higher than that in adults. Furthermore, adding exogenous lactic acid bacteria, such as Enterococcus fecalis and Enterococcus fecium, to the fermentation system effectively increased the SCFAs concentration in the model intestinal system of the children. By contrast, adding E. fecalis, Lactobacillus rhamnosus, and E. fecium increased the content of the produced SCFAs in the system of adults. Those results indicate that EPS isolated from F. castaneus Imaz was effectively fermented in the simulated intestinal environments, and the fermentation capability was enhanced by adding microbial flora. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. Simulation of the early startup period of high-temperature heat pipes from the frozen state by a rarefied vapor self-diffusion model

    NASA Technical Reports Server (NTRS)

    Cao, Y.; Faghri, A.

    1993-01-01

    The heat pipe startup process is described physically and is divided into five periods for convenience of analysis. The literature survey revealed that none of the previous attempts to simulate the heat pipe startup process numerically were successful, since the rarefied vapor flow in the heat pipe was not considered. Therefore, a rarefied vapor self-diffusion model is proposed, and the early startup periods, in which the rarefied vapor flow is dominant within the heat pipe, are first simulated numerically. The numerical results show that large vapor density gradients existed along the heat pipe length, and the vapor flow reaches supersonic velocities when the density is extremely low. The numerical results are compared with the experimental data of the early startup period with good agreement.

  15. Analysis of problems with dry fermentation process for biogas production

    NASA Astrophysics Data System (ADS)

    Pilát, Peter; Patsch, Marek; Jandačka, Jozef

    2012-04-01

    The technology of dry anaerobic fermentation is still meeting with some scepticism, and therefore in most biogas plants are used wet fermentation technology. Fermentation process would be not complete without an optimal controlled condition: dry matter content, density, pH, and in particular the reaction temperature. If is distrust of dry fermentation eligible it was on the workplace of the Department of Power Engineering at University of Zilina built an experimental small-scale biogas station that allows analysis of optimal parameters of the dry anaerobic fermentation, in particular, however, affect the reaction temperature on yield and quality of biogas.

  16. Effects of dietary fermentable carbohydrates on energy metabolism in group-housed sows.

    PubMed

    Rijnen, M M; Verstegen, M W; Heetkamp, M J; Haaksma, J; Schrama, J W

    2001-01-01

    The effect of dietary nonstarch polysaccharide (NSP) content on the metabolic rate in group-housed sows was studied. Twelve groups of six nonpregnant sows were each fed one of four experimental diets similar in composition except for the starch and NSP content. Exchanging sugar beet pulp silage (SBPS) for tapioca created the difference in starch and NSP ratio in the diet. On a DM basis, diets contained 0, 10, 20, or 30% SBPS. Sows were group-housed and fed at 1.30 times the assumed maintenance energy requirements. Nitrogen and energy balances were measured per group during a 7-d experimental period, which was preceded by a 33-d adaptation period. Both digestibility and metabolizability of energy decreased with increasing dietary SBPS content (P < 0.05). Heat production and energy retention were unaffected by the exchange of starch for NSP (P > 0.1). Based on energy retention data and apparent fecal digestibilities of crude protein, crude fat, starch, and NSP, the estimated net energy value of fermented NSP was 13.4 kJ/g. The present study shows that group-housed sows are capable of using energy from fermented NSP (i.e., NSP from SBPS) as efficiently as energy from digested starch (i.e., starch from tapioca).

  17. Review: Diversity of Microorganisms in Global Fermented Foods and Beverages

    PubMed Central

    Tamang, Jyoti P.; Watanabe, Koichi; Holzapfel, Wilhelm H.

    2016-01-01

    Culturalable and non-culturable microorganisms naturally ferment majority of global fermented foods and beverages. Traditional food fermentation represents an extremely valuable cultural heritage in most regions, and harbors a huge genetic potential of valuable but hitherto undiscovered strains. Holistic approaches for identification and complete profiling of both culturalable and non-culturable microorganisms in global fermented foods are of interest to food microbiologists. The application of culture-independent technique has thrown new light on the diversity of a number of hitherto unknown and non-cultural microorganisms in naturally fermented foods. Functional bacterial groups (“phylotypes”) may be reflected by their mRNA expression in a particular substrate and not by mere DNA-level detection. An attempt has been made to review the microbiology of some fermented foods and alcoholic beverages of the world. PMID:27047484

  18. Invited review: Fermented milk as antihypertensive functional food.

    PubMed

    Beltrán-Barrientos, L M; Hernández-Mendoza, A; Torres-Llanez, M J; González-Córdova, A F; Vallejo-Córdoba, B

    2016-06-01

    Over the past decade, interest has risen in fermented dairy foods that promote health and could prevent diseases such as hypertension. This biological effect has mainly been attributed to bioactive peptides encrypted within dairy proteins that can be released during fermentation with specific lactic acid bacteria or during gastrointestinal digestion. The most studied bioactive peptides derived from dairy proteins are antihypertensive peptides; however, a need exists to review the different studies dealing with the evaluation of antihypertensive fermented milk before a health claim may be associated with the product. Thus, the objective of this overview was to present available information related to the evaluation of fermented milk containing antihypertensive peptides by in vitro and in vivo studies, which are required before a fermented functional dairy product may be introduced to the market. Although commercial fermented milks with antihypertensive effects exist, these are scarce and most are based on Lactobacillus helveticus. Thus, a great opportunity is available for the development of functional dairy products with new lactic acid bacteria that support heart health through blood pressure- and heart rate-lowering effects. Hence, the consumer may be willing to pay a premium for foods with important functional benefits. Copyright © 2016 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  19. Sucrose fermentation by Saccharomyces cerevisiae lacking hexose transport.

    PubMed

    Batista, Anderson S; Miletti, Luiz C; Stambuk, Boris U

    2004-01-01

    Sucrose is the major carbon source used by Saccharomyces cerevisiae during production of baker's yeast, fuel ethanol and several distilled beverages. It is generally accepted that sucrose fermentation proceeds through extracellular hydrolysis of the sugar, mediated by the periplasmic invertase, producing glucose and fructose that are transported into the cells and metabolized. In the present work we analyzed the contribution to sucrose fermentation of a poorly characterized pathway of sucrose utilization by S. cerevisiae cells, the active transport of the sugar through the plasma membrane and its intracellular hydrolysis. A yeast strain that lacks the major hexose transporters (hxt1-hxt7 and gal2) is incapable of growing on or fermenting glucose or fructose. Our results show that this hxt-null strain is still able to ferment sucrose due to direct uptake of the sugar into the cells. Deletion of the AGT1 gene, which encodes a high-affinity sucrose-H(+) symporter, rendered cells incapable of sucrose fermentation. Since sucrose is not an inducer of the permease, expression of the AGT1 must be constitutive in order to allow growth of the hxt-null strain on sucrose. The molecular characterization of active sucrose transport and fermentation by S. cerevisiae cells opens new opportunities to optimize yeasts for sugarcane-based industrial processes.

  20. Kombucha tea fermentation: Microbial and biochemical dynamics.

    PubMed

    Chakravorty, Somnath; Bhattacharya, Semantee; Chatzinotas, Antonis; Chakraborty, Writachit; Bhattacharya, Debanjana; Gachhui, Ratan

    2016-03-02

    Kombucha tea, a non-alcoholic beverage, is acquiring significant interest due to its claimed beneficial properties. The microbial community of Kombucha tea consists of bacteria and yeast which thrive in two mutually non-exclusive compartments: the soup or the beverage and the biofilm floating on it. The microbial community and the biochemical properties of the beverage have so far mostly been described in separate studies. This, however, may prevent understanding the causal links between the microbial communities and the beneficial properties of Kombucha tea. Moreover, an extensive study into the microbial and biochemical dynamics has also been missing. In this study, we thus explored the structure and dynamics of the microbial community along with the biochemical properties of Kombucha tea at different time points up to 21 days of fermentation. We hypothesized that several biochemical properties will change during the course of fermentation along with the shifts in the yeast and bacterial communities. The yeast community of the biofilm did not show much variation over time and was dominated by Candida sp. (73.5-83%). The soup however, showed a significant shift in dominance from Candida sp. to Lachancea sp. on the 7th day of fermentation. This is the first report showing Candida as the most dominating yeast genus during Kombucha fermentation. Komagateibacter was identified as the single largest bacterial genus present in both the biofilm and the soup (~50%). The bacterial diversity was higher in the soup than in the biofilm with a peak on the seventh day of fermentation. The biochemical properties changed with the progression of the fermentation, i.e., beneficial properties of the beverage such as the radical scavenging ability increased significantly with a maximum increase at day 7. We further observed a significantly higher D-saccharic acid-1,4-lactone content and caffeine degradation property compared to previously described Kombucha tea fermentations. Our

  1. Changes in selected physical property and enzyme activity of rice and barley koji during fermentation and storage.

    PubMed

    Bechman, Allison; Phillips, Robert D; Chen, Jinru

    2012-06-01

    Koji are solid-state fermentation products made by inoculating steamed grains with the spores of fungi, particularly Aspergillus spp. This research was undertaken to identify the fermentation and storage conditions optimal for the production and maintenance of selected hydrolytic enzymes, such as α-amlyase and protease, in koji. Steamed rice and barley were inoculated with 2 × 10 ¹¹ Aspergillus oryzae spores per kilogram of grains and fermented for 118 h in a growth chamber at 28 to 32 °C with controlled relative humidities. Samples were drawn periodically during fermentation and storage at -20, 4, or 32 °C, and α-amylase and protease activity, mold counts, a(w), moisture contents, and pH of collected samples were determined. It was observed that the a(w), moisture contents, and pH of the koji were influenced by the duration of fermentation and temperature of storage. The α-amylase activity of both koji increased as the populations of A. oryzae increased during the exponential growth phase. The enzyme activity of barley koji was significantly higher than that of rice koji, reaching a peak activity of 211.87 or 116.57 U at 46 and 58 h, respectively, into the fermentation process. The enzyme activity in both products started to decrease once the mold culture entered the stationary growth phase. The protease activities of both koji were low and remained relatively stable during fermentation and storage. These results suggest that rice and barley koji can be used as sources of α-amylase and desired enzyme activity can be achieved by controlling the fermentation and storage conditions. Amylases and proteases are 2 important hydrolytic enzymes. In the food industry, these enzymes are used to break down starches and proteins while reducing the viscosity of foods. Although amylases and proteases are found in plants and animals, commercial enzymes are often produced using bacteria or molds through solid state fermentation, which is designed to use natural microbial

  2. Fermented foods, neuroticism, and social anxiety: An interaction model.

    PubMed

    Hilimire, Matthew R; DeVylder, Jordan E; Forestell, Catherine A

    2015-08-15

    Animal models and clinical trials in humans suggest that probiotics can have an anxiolytic effect. However, no studies have examined the relationship between probiotics and social anxiety. Here we employ a cross-sectional approach to determine whether consumption of fermented foods likely to contain probiotics interacts with neuroticism to predict social anxiety symptoms. A sample of young adults (N=710, 445 female) completed self-report measures of fermented food consumption, neuroticism, and social anxiety. An interaction model, controlling for demographics, general consumption of healthful foods, and exercise frequency, showed that exercise frequency, neuroticism, and fermented food consumption significantly and independently predicted social anxiety. Moreover, fermented food consumption also interacted with neuroticism in predicting social anxiety. Specifically, for those high in neuroticism, higher frequency of fermented food consumption was associated with fewer symptoms of social anxiety. Taken together with previous studies, the results suggest that fermented foods that contain probiotics may have a protective effect against social anxiety symptoms for those at higher genetic risk, as indexed by trait neuroticism. While additional research is necessary to determine the direction of causality, these results suggest that consumption of fermented foods that contain probiotics may serve as a low-risk intervention for reducing social anxiety. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  3. The impact of yeast fermentation on dough matrix properties.

    PubMed

    Rezaei, Mohammad N; Jayaram, Vinay B; Verstrepen, Kevin J; Courtin, Christophe M

    2016-08-01

    Most studies on dough properties are performed on yeastless dough to exclude the complicating, time-dependent effect of yeast. Baker's yeast, however, impacts dough matrix properties during fermentation, probably through the production of primary (CO2 and ethanol) and secondary (glycerol, acetic acid and succinic acid) metabolites. The aim of this study is to obtain a better understanding of the changes in yeasted dough behavior introduced by fermentation, by investigating the impact of yeast fermentation on Farinograph dough consistency, dough spread, Kieffer rig dough extensibility and gluten agglomeration behavior in a fermented dough-batter gluten starch separation system. Results show that fermentation leads to a dough with less flow and lower extensibility that breaks more easily under stress and strain. The dough showed less elastic and more plastic deformation behavior. Gluten agglomerates were smaller for yeasted dough than for the unyeasted control. These changes probably have to be attributed to metabolites generated during fermentation. Indeed, organic acids and also ethanol in concentrations produced by yeast were previously shown to have similar effects in yeastless dough. These findings imply the high importance of yeast fermentation metabolites on dough matrix properties in industrial bread production. © 2015 Society of Chemical Industry. © 2015 Society of Chemical Industry.

  4. Digestion, absorption, and fermentation of carbohydrates in the newborn.

    PubMed

    Kien, C L

    1996-06-01

    In the newborn, sugars present in human milk and formulas are assimilated by both small intestinal digestion and, especially in the case of lactose, colonic bacterial fermentation. Colonic fermentation of carbohydrate serves three major functions: (1) conservation of a fraction of the metabolizable energy of dietary carbohydrate that is not absorbed in the small intestine; (2) prevention of osmotic diarrhea; and (3) production of short-chain fatty acids that stimulate sodium and water absorption, serve as fuel for colonocytes, and stimulate cell replication in colon and small intestine. Diarrhea produced in association with small bowel malabsorption of sugar may be caused by three, potentially overlapping mechanisms: (1) osmotic effects of unfermented sugar, which may cause secondary disruption of fermentation by purging the bacteria or diluting the bacteria mass; (2) damage to the colon mucosa from excessive fermentation leading to SCFA malabsorption and osmotic diarrhea on this basis; and (3) excessive fermentation leading to lowering of luminal pH and inhibition of bacterial enzymes. Therapy aimed at reducing diarrhea associated with sugar malabsorption might involve either slowing of motility to facilitate fermentation or stimulation of fermentative activity, but such interventions would depend on greater understanding of the mechanisms for colonic dysfunction in this condition.

  5. Fermentation: From Sensory Experience to Conceptual Understanding

    ERIC Educational Resources Information Center

    Moore, Eugene B.

    1977-01-01

    Presented is a laboratory exercise that utilizes the natural yeast carbonation method of making homemade root beer to study fermentation and the effect of variables upon the fermentation process. There are photographs, a sample data sheet, and procedural hints included. (Author/MA)

  6. Prediction of rhythmic and periodic EEG patterns and seizures on continuous EEG with early epileptiform discharges.

    PubMed

    Koren, J; Herta, J; Draschtak, S; Pötzl, G; Pirker, S; Fürbass, F; Hartmann, M; Kluge, T; Baumgartner, C

    2015-08-01

    Continuous EEG (cEEG) is necessary to document nonconvulsive seizures (NCS), nonconvulsive status epilepticus (NCSE), as well as rhythmic and periodic EEG patterns of 'ictal-interictal uncertainty' (RPPIIU) including periodic discharges, rhythmic delta activity, and spike-and-wave complexes in neurological intensive care patients. However, cEEG is associated with significant recording and analysis efforts. Therefore, predictors from short-term routine EEG with a reasonably high yield are urgently needed in order to select patients for evaluation with cEEG. The aim of this study was to assess the prognostic significance of early epileptiform discharges (i.e., within the first 30 min of EEG recording) on the following: (1) incidence of ictal EEG patterns and RPPIIU on subsequent cEEG, (2) occurrence of acute convulsive seizures during the ICU stay, and (3) functional outcome after 6 months of follow-up. We conducted a separate analysis of the first 30 min and the remaining segments of prospective cEEG recordings according to the ACNS Standardized Critical Care EEG Terminology as well as NCS criteria and review of clinical data of 32 neurological critical care patients. In 17 patients with epileptiform discharges within the first 30 min of EEG (group 1), electrographic seizures were observed in 23.5% (n = 4), rhythmic or periodic EEG patterns of 'ictal-interictal uncertainty' in 64.7% (n = 11), and neither electrographic seizures nor RPPIIU in 11.8% (n = 2). In 15 patients with no epileptiform discharges in the first 30 min of EEG (group 2), no electrographic seizures were recorded on subsequent cEEG, RPPIIU were seen in 26.7% (n = 4), and neither electrographic seizures nor RPPIIU in 73.3% (n = 11). The incidence of EEG patterns on cEEG was significantly different between the two groups (p = 0.008). Patients with early epileptiform discharges developed acute seizures more frequently than patients without early epileptiform discharges (p = 0.009). Finally, functional

  7. Simultaneous Saccharification and Fermentation and Partial Saccharification and Co-Fermentation of Lignocellulosic Biomass for Ethanol Production

    NASA Astrophysics Data System (ADS)

    Doran-Peterson, Joy; Jangid, Amruta; Brandon, Sarah K.; Decrescenzo-Henriksen, Emily; Dien, Bruce; Ingram, Lonnie O.

    Ethanol production by fermentation of lignocellulosic biomass-derived sugars involves a fairly ancient art and an ever-evolving science. Production of ethanol from lignocellulosic biomass is not avant-garde, and wood ethanol plants have been in existence since at least 1915. Most current ethanol production relies on starch- and sugar-based crops as the substrate; however, limitations of these materials and competing value for human and animal feeds is renewing interest in lignocellulose conversion. Herein, we describe methods for both simultaneous saccharification and fermentation (SSF) and a similar but separate process for partial saccharification and cofermentation (PSCF) of lignocellulosic biomass for ethanol production using yeasts or pentose-fermenting engineered bacteria. These methods are applicable for small-scale preliminary evaluations of ethanol production from a variety of biomass sources.

  8. Production of Star Fruit Alcoholic Fermented Beverage.

    PubMed

    Valim, Flávia de Paula; Aguiar-Oliveira, Elizama; Kamimura, Eliana Setsuko; Alves, Vanessa Dias; Maldonado, Rafael Resende

    2016-12-01

    Star fruit ( Averrhoa carambola ) is a nutritious tropical fruit. The aim of this study was to evaluate the production of a star fruit alcoholic fermented beverage utilizing a lyophilized commercial yeast ( Saccharomyces cerevisiae ). The study was conducted utilizing a 2 3 central composite design and the best conditions for the production were: initial soluble solids between 23.8 and 25 °Brix (g 100 g -1 ), initial pH between 4.8 and 5.0 and initial concentration of yeast between 1.6 and 2.5 g L -1 . These conditions yielded a fermented drink with an alcohol content of 11.15 °GL (L 100 L -1 ), pH of 4.13-4.22, final yeast concentration of 89 g L -1 and fermented yield from 82 to 94 %. The fermented drink also presented low levels of total and volatile acidities.

  9. Antioxidant properties of certain cereals as affected by food-grade bacteria fermentation.

    PubMed

    Wang, Chung-Yi; Wu, Sz-Jie; Shyu, Yuan-Tay

    2014-04-01

    The effects of fermentation by 2 food-grade bacteria (Bacillus subtilis and Lactobacillus plantarum) on antioxidant activities and the contents of phenolics and flavonoids in 4 cereals (specifically adlay, chestnut, lotus seed, and walnut) were determined and compared with those of their non-fermented counterparts. Results showed that antioxidant properties observed in the fermented and non-fermented cereals may vary with fermented starters. Fermentation was observed to increase the phenolic and flavonoid contents of the extracts. The effects on Bacillus-fermented cereals were stronger than on Lactobacillus-fermented cereals. In IC50 values (mg/mL) of extracts, the extracts of fermented cereal showed a stronger DPPH radical scavenging and ferric-reducing activities. Fermentation did not significantly alter the Fe(2+)-chelating activity in the extracts of chestnuts and lotus seeds. All cereals were shown significantly inhibited the production of LPS-induced intracellular reactive oxygen species (ROS) without creating obvious cytotoxic effects in the macrophage cells. These results suggest that the fermentation process enables cereal-based foods with enhanced antioxidant capacities to contribute to health and nutritional improvements in consumers. Copyright © 2013 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  10. Procedure of brewing alcohol as a staple food: case study of the fermented cereal liquor "Parshot" as a staple food in Dirashe special woreda, southern Ethiopia.

    PubMed

    Sunano, Yui

    2016-07-01

    For most brews, alcohol fermentation and lactic fermentation take place simultaneously during the brewing process, and alcohol fermentation can progress smoothly because the propagation of various microorganisms is prevented by lactic fermentation. It is not necessary to cause lactic fermentation with a thing generated naturally and intentionally. The people living in the Dirashe area in southern Ethiopia drink three types of alcoholic beverages that are prepared from cereals. From these alcoholic beverages, parshot is prepared by the addition of plant leaves for lactic fermentation and nech chaka by adding cereal powder for lactic fermentation before alcohol fermentation. People living in the Dirashe area partake of parshot as part of their staple diet. The brewing process used for parshot and a food culture with alcoholic beverages as parts of the staple diet are rare worldwide. This article discusses the significance of using lactic fermentation before alcoholic fermentation and focuses on lactic fermentation in the brewing methods used for the three kinds of alcoholic beverages consumed in the Dirashe area. We initially observed the brewing process and obtained information about the process from the people in that area. Next, we determined the pH and analyzed the lactic acid (g/100 g) and ethanol (g/100 g) content during lactic fermentation of parshot and nech chaka; the ethyl acetate (mg/100 g) and volatile base nitrogen (mg/100 g) content during this period was also analyzed. In addition, we compared the ethanol (g/100 g) content of all three kinds of alcoholic beverages after completion of brewing. The results showed that it was possible to consume large quantities of these alcoholic beverages because of the use of lactic fermentation before alcoholic fermentation, which improved the safety and preservation characteristics of the beverages by preventing the propagation of various microorganisms, improving flavor, and controlling the alcohol level.

  11. African fermented foods and probiotics.

    PubMed

    Franz, Charles M A P; Huch, Melanie; Mathara, Julius Maina; Abriouel, Hikmate; Benomar, Nabil; Reid, Gregor; Galvez, Antonio; Holzapfel, Wilhelm H

    2014-11-03

    Africa has an age old history of production of traditional fermented foods and is perhaps the continent with the richest variety of lactic acid fermented foods. These foods have a large impact on the nutrition, health and socio-economy of the people of the continent, often plagued by war, drought, famine and disease. Sub-Saharan Africa is the world's region with the highest percentage of chronically malnourished people and high child mortality. Further developing of traditional fermented foods with added probiotic health features would be an important contribution towards reaching the UN Millennium Development Goals of eradication of poverty and hunger, reduction in child mortality rates and improvement of maternal health. Specific probiotic strains with documented health benefits are sparsely available in Africa and not affordable to the majority of the population. Furthermore, they are not used in food fermentations. If such probiotic products could be developed especially for household food preparation, such as cereal or milk foods, it could make a profound impact on the health and well-being of adults and children. Suitable strains need to be chosen and efforts are needed to produce strains to make products which will be available for clinical studies. This can gauge the impact of probiotics on consumers' nutrition and health, and increase the number of people who can benefit. Copyright © 2014 Elsevier B.V. All rights reserved.

  12. The Microbial Diversity of Traditional Spontaneously Fermented Lambic Beer

    PubMed Central

    Spitaels, Freek; Wieme, Anneleen D.; Janssens, Maarten; Aerts, Maarten; Daniel, Heide-Marie; Van Landschoot, Anita; De Vuyst, Luc; Vandamme, Peter

    2014-01-01

    Lambic sour beers are the products of a spontaneous fermentation that lasts for one to three years before bottling. The present study determined the microbiota involved in the fermentation of lambic beers by sampling two fermentation batches during two years in the most traditional lambic brewery of Belgium, using culture-dependent and culture-independent methods. From 14 samples per fermentation, over 2000 bacterial and yeast isolates were obtained and identified. Although minor variations in the microbiota between casks and batches and a considerable species diversity were found, a characteristic microbial succession was identified. This succession started with a dominance of Enterobacteriaceae in the first month, which were replaced at 2 months by Pediococcus damnosus and Saccharomyces spp., the latter being replaced by Dekkera bruxellensis at 6 months fermentation duration. PMID:24748344

  13. The microbial diversity of traditional spontaneously fermented lambic beer.

    PubMed

    Spitaels, Freek; Wieme, Anneleen D; Janssens, Maarten; Aerts, Maarten; Daniel, Heide-Marie; Van Landschoot, Anita; De Vuyst, Luc; Vandamme, Peter

    2014-01-01

    Lambic sour beers are the products of a spontaneous fermentation that lasts for one to three years before bottling. The present study determined the microbiota involved in the fermentation of lambic beers by sampling two fermentation batches during two years in the most traditional lambic brewery of Belgium, using culture-dependent and culture-independent methods. From 14 samples per fermentation, over 2000 bacterial and yeast isolates were obtained and identified. Although minor variations in the microbiota between casks and batches and a considerable species diversity were found, a characteristic microbial succession was identified. This succession started with a dominance of Enterobacteriaceae in the first month, which were replaced at 2 months by Pediococcus damnosus and Saccharomyces spp., the latter being replaced by Dekkera bruxellensis at 6 months fermentation duration.

  14. Time course effects of fermentation on fatty acid and volatile compound profiles of Cheonggukjang using new soybean cultivars.

    PubMed

    Cho, Kye Man; Lim, Ho-Jeong; Kim, Mi-So; Kim, Da Som; Hwang, Chung Eun; Nam, Sang Hae; Joo, Ok Soo; Lee, Byong Won; Kim, Jae Kyeom; Shin, Eui-Cheol

    2017-07-01

    In this study, we investigated the effects of the potential probiotic Bacillus subtilis CSY191 on the fatty acid profiles of Cheonggukjang, a fermented soybean paste, prepared using new Korean brown soybean cultivars, protein-rich cultivar (Saedanbaek), and oil-rich cultivar (Neulchan). Twelve fatty acids were identified in the sample set-myristic, palmitic, palmitoleic, stearic, oleic, vaccenic, linoleic, α-linolenic, arachidic, gondoic, behenic, and lignoceric acids-yet, no specific changes driven by fermentation were noted in the fatty acid profiles. To further explore the effects of fermentation of B. subtilis CSY191, complete profiles of volatiles were monitored. In total, 121, 136, and 127 volatile compounds were detected in the Saedanbaek, Daewon (control cultivar), and Neulchan samples, respectively. Interestingly, the content of pyrazines-compounds responsible for pungent and unpleasant Cheonggukjang flavors-was significantly higher in Neulchan compared to that in Saedanbaek. Although the fermentation period was not a strong factor affecting the observed changes in fatty acid profiles, we noted that profiles of volatiles in Cheonggukjang changed significantly over time, and different cultivars represented specific volatile profiles. Thus, further sensory evaluation might be needed to determine if such differences influence consumers' preferences. Furthermore, additional studies to elucidate the associations between B. subtilis CSY191 fermentation and other nutritional components (e.g., amino acids) and their health-promoting potential are warranted. Copyright © 2016. Published by Elsevier B.V.

  15. Effects of mineral salt supplement on enteric methane emissions, ruminal fermentation and methanogen community of lactating cows.

    PubMed

    Li, Xiaohua; Liu, Chong; Chen, Yongxing; Shi, Rongguang; Cheng, Zhenhua; Dong, Hongmin

    2017-08-01

    We evaluated the effects of mineral salt supplement on enteric methane emissions, ruminal fermentation and methanogen community of dairy cows over a whole lactation period. Ten Holstein cows fed a total mixed ration (TMR) diet were randomly allocated into two groups, one supplied with mineral salts as the treatment group and the other as the control group. The methane measurement showed that the ingestion of mineral salts lowered enteric methane emissions significantly (P < 0.05), with an average of 10.5% reduction over the whole lactation period. Ruminal fermentation analysis showed the mineral salt intake could significantly decrease the acetate : propionate ratio (P < 0.05). Real-time PCR assay showed that rumen methanogen abundance significantly reduced in the treatment group (P < 0.05) but was not significantly influenced by mineral salt intake over the whole lactation period. Intergroup methanogen community composition was influenced slightly by mineral salt intake; however, significantly different intragroup profiles were apparent throughout the whole lactation period, according to denaturing gradient gel electrophoresis analysis. In conclusion, these results suggested that the effective mitigation of enteric methane emissions by mineral salt intake could be attributed to decreased density of methanogenic archaea and that fluctuations in methane emission over the lactation period might be related to Methanobrevibacter diversity. © 2016 Japanese Society of Animal Science.

  16. Characteristics of Milk Fermented by Streptococcus thermophilus MGA45-4 and the Profiles of Associated Volatile Compounds during Fermentation and Storage.

    PubMed

    Dan, Tong; Jin, Rulin; Ren, Weiyi; Li, Ting; Chen, Haiyan; Sun, Tiansong

    2018-04-11

    The lactic acid bacterium Streptococcus thermophilus is a major starter culture for the production of dairy products. In this study, the physiochemical characteristics of milk fermented by the MGA45-4 isolate of S. thermophilus were analyzed. Our data indicate that milk fermented using S. thermophilus MGA45-4 maintained a high viable cell count (8.86 log10 colony-forming units/mL), and a relatively high pH (4.4), viscosity (834.33 mPa·s), and water holding capacity (40.85%) during 14 days of storage. By analyzing the volatile compound profile using solid-phase microextraction and gas chromatography/mass spectrometry, we identified 73 volatile compounds in the fermented milk product, including five carboxylic acids, 21 aldehydes, 13 ketones, 16 alcohols, five esters, and 13 aromatic carbohydrates. According to the odor activity values, 11 of these volatile compounds were found to play a key role in producing the characteristic flavor of fermented milk, particularly octanal, nonanal, hexanal, 2,3-butanedione, and 1-octen-3-ol, which had the highest odor activity values among all compounds analyzed. These findings thus provide more insights in the chemical/molecular characteristics of milk fermented using S. thermophilus , which may provide a basis for improving dairy product flavor/odor during the process of fermentation and storage.

  17. Promoting healthy food preferences from the start: a narrative review of food preference learning from the prenatal period through early childhood.

    PubMed

    Anzman-Frasca, S; Ventura, A K; Ehrenberg, S; Myers, K P

    2018-04-01

    The palatable, energy-dense foods that characterize modern environments can promote unhealthy eating habits, along with humans' predispositions to accept sweet tastes and reject those that are sour or bitter. Yet food preferences are malleable, and examining food preference learning during early life can highlight ways to promote acceptance of healthier foods. This narrative review describes research from the past 10 years focused on food preference learning from the prenatal period through early childhood (ages 2-5 years). Exposure to a variety of healthy foods from the start, including during the prenatal period, early milk-feeding and the introduction to complementary foods and beverages, can support subsequent acceptance of those foods. Yet development is plastic, and healthier food preferences can still be promoted after infancy. In early childhood, research supports starting with the simplest strategies, such as repeated exposure and modelling, reserving other strategies for use when needed to motivate the initial tasting necessary for repeated exposure effects to begin. This review can help caregivers and practitioners to promote the development of healthy food preferences early in life. Specific implementation recommendations, the role of individual differences and next steps for research in this area are also discussed. © 2017 World Obesity Federation.

  18. Rheology of corn stover slurries during fermentation to ethanol

    NASA Astrophysics Data System (ADS)

    Ghosh, Sanchari; Epps, Brenden; Lynd, Lee

    2017-11-01

    In typical processes that convert cellulosic biomass into ethanol fuel, solubilization of the biomass is carried out by saccharolytic enzymes; however, these enzymes require an expensive pretreatment step to make the biomass accessible for solubilization (and subsequent fermentation). We have proposed a potentially-less-expensive approach using the bacterium Clostridium thermocellum, which can initiate fermentation without pretreatment. Moreover, we have proposed a ``cotreatment'' process, in which fermentation and mechanical milling occur alternately so as to achieve the highest ethanol yield for the least milling energy input. In order to inform the energetic requirements of cotreatment, we experimentally characterized the rheological properties of corn stover slurries at various stages of fermentation. Results show that a corn stover slurry is a yield stress fluid, with shear thinning behavior well described by a power law model. Viscosity decreases dramatically upon fermentation, controlling for variables such as solids concentration and particle size distribution. To the authors' knowledge, this is the first study to characterize the changes in the physical properties of biomass during fermentation by a thermophilic bacterium.

  19. Optimization of fermentation conditions for alcohol production.

    PubMed

    Bowman, L; Geiger, E

    1984-12-01

    The quantitative effects of carbohydrate levels, degree of initial saccharification, glucoamylase dosage, temperature, and fermentation time were investigated using a Box-Wilson central composite design protocol. With Saccharomyces cerevisiae ATCC 4126, it was found that the use of a partially saccharified starch substrate markedly increased yields and attainable alcohol levels. Balancing the degree of initial saccharification with the level of glucoamylase used to complete hydrolysis was found necessary to obtain optimum yields. The temperature optimum was found to be 36 degrees C. The regression equations obtained were used to model the fermentation in order to determine optimum fermentation conditions.

  20. Antidiabetic Effect of Morinda citrifolia (Noni) Fermented by Cheonggukjang in KK-Ay Diabetic Mice

    PubMed Central

    Lee, So-Young; Park, So-Lim; Hwang, Jin-Taek; Yi, Sung-Hun; Nam, Young-Do; Lim, Seong-Il

    2012-01-01

    Antidiabetic effects of Morinda citrifolia (aka Noni) fermented by Cheonggukjang (fast-fermented soybean paste) were evaluated using a T2DM (type 2 diabetes mellitus) murine model. Six-week-old KK-Ay/TaJcl mice were randomly divided into four groups: (1) the diabetic control (DC) group, provided with a normal mouse diet; (2) the positive control (PC) group, provided with a functional health food diet; (3) the M. citrifolia (MC) group, provided with an MC-based diet; (4) the fermented M. citrifolia (FMC) group, provided with an FMC-based diet. Over a testing period of 90 days, food and water intake decreased significantly in the FMC and PC groups compared with the DC group. Blood glucose levels in the FMC group were 211.60–252.20 mg/dL after 90 days, while those in the control group were over 400 mg/dL after 20 days. In addition, FMC supplementation reduced glycosylated hemoglobin (HbA1c) levels, enhanced insulin sensitivity, and significantly decreased serum triglycerides and low-density lipoprotein (LDL) cholesterol. Furthermore, a fermented M. citrifolia 70% ethanolic extract (FMCE) activated peroxisome proliferator-activated receptor-(PPAR-) γ and stimulated glucose uptake via stimulation of AMP-activated protein kinase (AMPK) in cultured C2C12 cells. These results suggest that FMC can be employed as a functional health food for T2DM management. PMID:22969823

  1. Cocoa pulp in beer production: Applicability and fermentative process performance.

    PubMed

    Nunes, Cassiane da Silva Oliveira; de Carvalho, Giovani Brandão Mafra; da Silva, Marília Lordêlo Cardoso; da Silva, Gervásio Paulo; Machado, Bruna Aparecida Souza; Uetanabaro, Ana Paula Trovatti

    2017-01-01

    This work evaluated the effect of cocoa pulp as a malt adjunct on the parameters of fermentation for beer production on a pilot scale. For this purpose, yeast isolated from the spontaneous fermentation of cachaça (SC52), belonging to the strain bank of the State University of Feira de Santana-Ba (Brazil), and a commercial strain of ale yeast (Safale S-04 Belgium) were used. The beer produced was subjected to acceptance and purchase intention tests for sensorial analysis. At the beginning of fermentation, 30% cocoa pulp (adjunct) was added to the wort at 12°P concentration. The production of beer on a pilot scale was carried out in a bioreactor with a 100-liter capacity, a usable volume of 60 liters, a temperature of 22°C and a fermentation time of 96 hours. The fermentation parameters evaluated were consumption of fermentable sugars and production of ethanol, glycerol and esters. The beer produced using the adjunct and yeast SC52 showed better fermentation performance and better acceptance according to sensorial analysis.

  2. Cocoa pulp in beer production: Applicability and fermentative process performance

    PubMed Central

    de Carvalho, Giovani Brandão Mafra; da Silva, Gervásio Paulo

    2017-01-01

    This work evaluated the effect of cocoa pulp as a malt adjunct on the parameters of fermentation for beer production on a pilot scale. For this purpose, yeast isolated from the spontaneous fermentation of cachaça (SC52), belonging to the strain bank of the State University of Feira de Santana-Ba (Brazil), and a commercial strain of ale yeast (Safale S-04 Belgium) were used. The beer produced was subjected to acceptance and purchase intention tests for sensorial analysis. At the beginning of fermentation, 30% cocoa pulp (adjunct) was added to the wort at 12°P concentration. The production of beer on a pilot scale was carried out in a bioreactor with a 100-liter capacity, a usable volume of 60 liters, a temperature of 22°C and a fermentation time of 96 hours. The fermentation parameters evaluated were consumption of fermentable sugars and production of ethanol, glycerol and esters. The beer produced using the adjunct and yeast SC52 showed better fermentation performance and better acceptance according to sensorial analysis. PMID:28419110

  3. Continuous energy recovery and nutrients removal from molasses wastewater by synergistic system of dark fermentation and algal culture under various fermentation types.

    PubMed

    Ren, Hong-Yu; Kong, Fanying; Ma, Jun; Zhao, Lei; Xie, Guo-Jun; Xing, Defeng; Guo, Wan-Qian; Liu, Bing-Feng; Ren, Nan-Qi

    2018-03-01

    Synergistic system of dark fermentation and algal culture was initially operated at batch mode to investigate the energy production and nutrients removal from molasses wastewater in butyrate-type, ethanol-type and propionate-type fermentations. Butyrate-type fermentation was the most appropriate fermentation type for the synergistic system and exhibited the accumulative hydrogen volume of 658.3 mL L -1 and hydrogen yield of 131.7 mL g -1 COD. By-products from dark fermentation (mainly acetate and butyrate) were further used to cultivate oleaginous microalgae. The maximum algal biomass and lipid content reached 1.01 g L -1 and 38.5%, respectively. In continuous operation, the synergistic system was stable and efficient, and energy production increased from 8.77 kJ L -1  d -1 (dark fermentation) to 17.3 kJ L -1  d -1 (synergistic system). Total COD, TN and TP removal efficiencies in the synergistic system reached 91.1%, 89.1% and 85.7%, respectively. This study shows the potential of the synergistic system in energy recovery and wastewater treatment. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. Demonstration-Scale High-Cell-Density Fermentation of Pichia pastoris.

    PubMed

    Liu, Wan-Cang; Zhu, Ping

    2018-01-01

    Pichia pastoris has been one of the most successful heterologous overexpression systems in generating proteins for large-scale production through high-cell-density fermentation. However, optimizing conditions of the large-scale high-cell-density fermentation for biochemistry and industrialization is usually a laborious and time-consuming process. Furthermore, it is often difficult to produce authentic proteins in large quantities, which is a major obstacle for functional and structural features analysis and industrial application. For these reasons, we have developed a protocol for efficient demonstration-scale high-cell-density fermentation of P. pastoris, which employs a new methanol-feeding strategy-biomass-stat strategy and a strategy of increased air pressure instead of pure oxygen supplement. The protocol included three typical stages of glycerol batch fermentation (initial culture phase), glycerol fed-batch fermentation (biomass accumulation phase), and methanol fed-batch fermentation (induction phase), which allows direct online-monitoring of fermentation conditions, including broth pH, temperature, DO, anti-foam generation, and feeding of glycerol and methanol. Using this protocol, production of the recombinant β-xylosidase of Lentinula edodes origin in 1000-L scale fermentation can be up to ~900 mg/L or 9.4 mg/g cells (dry cell weight, intracellular expression), with the specific production rate and average specific production of 0.1 mg/g/h and 0.081 mg/g/h, respectively. The methodology described in this protocol can be easily transferred to other systems, and eligible to scale up for a large number of proteins used in either the scientific studies or commercial purposes.

  5. Nutritional Value of Rice Bran Fermented by Bacillus amyloliquefaciens and Humic Substances and Its Utilization as a Feed Ingredient for Broiler Chickens.

    PubMed

    Supriyati; Haryati, T; Susanti, T; Susana, I W R

    2015-02-01

    An experiment was conducted to increase the quality of rice bran by fermentation using Bacillus amyloliquefaciens and humic substances and its utilization as a feed ingredient for broiler chickens. The experiment was carried out in two steps. First, the fermentation process was done using a completely randomized design in factorial with 16 treatments: i) Dosage of B. amyloliquefaciens (2.10(8) cfu/g), 10 and 20 g/kg; ii) Graded levels of humic substances, 0, 100, 200, and 400 ppm; iii) Length of fermentation, three and five days. The results showed that the fermentation significantly (p<0.05) reduced crude fiber content. The recommended conditions for fermentation of rice bran: 20 g/kg dosage of inoculums B. amyloliquefaciens, 100 ppm level of humic substances and three days fermentation period. The second step was a feeding trial to evaluate the fermented rice bran (FRB) as a feed ingredient for broiler chickens. Three hundred and seventy-five one-day-old broiler chicks were randomly assigned into five treatment diets. Arrangement of the diets as follows: 0%, 5%, 10%, 15%, and 20% level of FRB and the diets formulation based on equal amounts of energy and protein. The results showed that 15% inclusion of FRB in the diet provided the best bodyweight gain and feed conversion ratio (FCR) values. In conclusion, the nutrient content of rice bran improved after fermentation and the utilization of FRB as a feed ingredient for broiler chickens could be included up to 15% of the broiler diet.

  6. Fermentation and recovery process for lactic acid production

    DOEpatents

    Tsai, S.P.; Moon, S.H.; Coleman, R.

    1995-11-07

    A method is described for converting starch to glucose and fermenting glucose to lactic acid, including simultaneous saccharification and fermentation through use of a novel consortium of bacterial strains. 2 figs.

  7. Vision-Based Sensor for Early Detection of Periodical Defects in Web Materials

    PubMed Central

    Bulnes, Francisco G.; Usamentiaga, Rubén; García, Daniel F.; Molleda, Julio

    2012-01-01

    During the production of web materials such as plastic, textiles or metal, where there are rolls involved in the production process, periodically generated defects may occur. If one of these rolls has some kind of flaw, it can generate a defect on the material surface each time it completes a full turn. This can cause the generation of a large number of surface defects, greatly degrading the product quality. For this reason, it is necessary to have a system that can detect these situations as soon as possible. This paper presents a vision-based sensor for the early detection of this kind of defects. It can be adapted to be used in the inspection of any web material, even when the input data are very noisy. To assess its performance, the sensor system was used to detect periodical defects in hot steel strips. A total of 36 strips produced in ArcelorMittal Avilés factory were used for this purpose, 18 to determine the optimal configuration of the proposed sensor using a full-factorial experimental design and the other 18 to verify the validity of the results. Next, they were compared with those provided by a commercial system used worldwide, showing a clear improvement. PMID:23112629

  8. Physical and Sensory Properties of Ice Cream Containing Fermented Pepper Powder.

    PubMed

    Yeon, Su-Jung; Kim, Ji-Han; Hong, Go-Eun; Park, Woojoon; Kim, Soo-Ki; Seo, Han-Geuk; Lee, Chi-Ho

    2017-01-01

    This study was conducted to investigate the physical and sensory properties of ice cream containing fermented pepper powder. Three ice cream formulas were manufactured: 1, control; 2, supplemented with 0.1% fermented pepper powder; and 3, supplemented with 0.2% fermented pepper powder. Formulas 2 and 3 had significantly higher viscosity and lower overrun than formula 1 ( p <0.05). Additionally, ice creams supplemented with fermented pepper powder were harder and maintained their forms longer than the controls. 0.2% fermented pepper powder added ice cream had no pungency as much as that of control and overall sensory attribute was not significantly different from control. Therefore, ice cream containing fermented pepper powder maintained physical and sensory properties similar to the controls, and maintenance was better. It means fermented pepper powder ice cream can be utilized as the material of functional food (dessert).

  9. PERVAPORATION MEMBRANE SYSTEMS FOR VOLATILE FERMENTATION PRODUCT RECOVERY AND DEHYDRATION

    EPA Science Inventory

    The economics of fermentative production of fuels and commodity chemicals can be a strong function of the efficiency with which the fermentation products are removed from the biological media. Due to growth inhibition by some fermentation products, including ethanol, concentrati...

  10. Process for the fermentative production of acetone, butanol and ethanol

    DOEpatents

    Glassner, David A.; Jain, Mahendra K.; Datta, Rathin

    1991-01-01

    A process including multistage continuous fermentation followed by batch fermentation with carefully chosen temperatures for each fermentation step, combined with an asporogenic strain of C. acetobutylicum and a high carbohydrate substrate concentration yields extraordinarily high butanol and total solvents concentrations.

  11. REDUCING WASTEWATER FROM CUCUMBER PICKLING PROCESS BY CONTROLLED CULTURE FERMENTATION

    EPA Science Inventory

    On a demonstration scale, the controlled culture fermentation process (CCF) developed by the U.S. Food Fermentation Laboratory was compared with the conventional natural fermentation process (NF) in regard to product quality and yield and volume and concentration of wastewaters. ...

  12. Metabolite profiling of the fermentation process of "yamahai-ginjo-shikomi" Japanese sake.

    PubMed

    Tatsukami, Yohei; Morisaka, Hironobu; Aburaya, Shunsuke; Aoki, Wataru; Kohsaka, Chihiro; Tani, Masafumi; Hirooka, Kiyoo; Yamamoto, Yoshihiro; Kitaoka, Atsushi; Fujiwara, Hisashi; Wakai, Yoshinori; Ueda, Mitsuyoshi

    2018-01-01

    Sake is a traditional Japanese alcoholic beverage prepared by multiple parallel fermentation of rice. The fermentation process of "yamahai-ginjo-shikomi" sake is mainly performed by three microbes, Aspergillus oryzae, Saccharomyces cerevisiae, and Lactobacilli; the levels of various metabolites fluctuate during the fermentation of sake. For evaluation of the fermentation process, we monitored the concentration of moderate-sized molecules (m/z: 200-1000) dynamically changed during the fermentation process of "yamahai-ginjo-shikomi" Japanese sake. This analysis revealed that six compounds were the main factors with characteristic differences in the fermentation process. Among the six compounds, four were leucine- or isoleucine-containing peptides and the remaining two were predicted to be small molecules. Quantification of these compounds revealed that their quantities changed during the month of fermentation process. Our metabolomic approach revealed the dynamic changes observed in moderate-sized molecules during the fermentation process of sake, and the factors found in this analysis will be candidate molecules that indicate the progress of "yamahai-ginjo-shikomi" sake fermentation.

  13. Ethanol fermentation of cassava starch pretreated with alkali

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Shin, Y.C.; Lee, S.Y.; Choe, Y.K.

    1986-04-01

    In view of the current industrial process for the conventional ethanol fermentation, in which raw starch materials are heated at 120 degrees C for 2 h, conditions for an alternative process were set: an overall time from saccharification to ethanol fermentation of within 3-4 days, an operation temperature of below 60 degrees C, an ethanol yield of over 93%, and a ratio of raw material to fermentation volume of within 1:4. To meet these conditions, previously a steeping method of starch materials in 0.5N HCl solution at 60 degrees C for 12 h were used, followed by combined actions ofmore » ..cap alpha..-amylase and glucoamylase. The ethanol yield from uncooked cassava starch treated under the conditions described was 95% after fermentation for 3 days with Saccharomyces cerevisiae. However, the use of a relatively higher concentration of acid for steeping is still a problem and gelatinization of starch materials is insufficient. This communication, therefore, describes effects of alkali steeping and structural change of starch granules on the ethanol fermentation. 8 references.« less

  14. [Determination of nosocomial infection incidence in mothers and newborns during the early postpartum period].

    PubMed

    Malavaud, S; Bou-Segonds, E; Berrebi, A; Castagno, R; Assouline, C; Connan, L

    2003-04-01

    We wished to determine the incidence of nosocomial infections in the mother and the newborn during the early postpartum period. Over a three-month period, the same investigator collected 50 different clinical and microbiological, standardized data related to infectious diseases in parturients and their newborns. Data were collected on 804 deliveries. The overall rate of nosocomial infection was 2.9% (23/804). For vaginal deliveries, the rate was 1.9% (12/615) and for deliveries by Cesarean section, the rate was 5.8% (11/189). Of 745 newborns followed until discharge from hospital, 0.7% (5/745) had a nosocomial infection. These results are in line with previously published rates of nosocomial infections, which varied between 0.2% to 2.3% for vaginal deliveries, 1.6% to 18.9% for Cesarean section, and 0.2 to 4% in newborns. Regular surveys of the incidence or the prevalence of nosocomial infections are necessary to monitor the effectiveness of educational programs, aimed to reduce hospital acquired infections.

  15. Effects of inoculation of commercial starter cultures on the quality and histamine accumulation in fermented sausages.

    PubMed

    Wang, Xinhui; Ren, Hongyang; Wang, Wei; Zhang, Yin; Bai, Ting; Li, Junxia; Zhu, Wenyou

    2015-02-01

    To meet the requirements of high-quality safe products, starter cultures are used to produce fermented sausages. The effects of 3 commercial starter cultures, namely SM-194, T-SPX, and SM-181, on histamine accumulation and quality parameters including microbial quality, pH, water activity, and total volatile base nitrogen, as well as the color and texture properties, were evaluated during the fermentation and ripening of fermented sausages. Although initial counts of Escherichia coli, Enterobacteriaceae, and Pseudomonas were similar in the 4 batches, the growth of these microorganisms was significantly inhibited (P < 0.05) in batches SM-194, T-SPX, and SM-181 throughout the fermentation and ripening period. The counts of E. coli, Enterobacteriaceae, and Pseudomonas increased to maximum levels of 3.89, 4.41, and 5.15 log10 colony forming units/g in the control sausages, respectively. At the end of ripening, the levels of histamine were 8.85, 0.32, 7.82, and 3.18 mg/kg for batches C, SM-194, T-SPX, and SM-181, respectively. The results revealed that commercial starter cultures, particularly starter cultures SM-194 and SM-181, made a great contribution to histamine reduction. In addition, batches inoculated with starter cultures showed a stronger acidification and lower level of total volatile base nitrogen than the control sample during production (P < 0.05). In conclusion, it seems that the inoculation of commercial starter cultures, particularly starter cultures SM-194 and SM-181, contributes to improving microbial quality, hygienic quality and food safety of fermented sausages. © 2015 Institute of Food Technologists®

  16. Comparison of microbial fermentation of high- and low-forage diets in Rusitec, single-flow continuous-culture fermenters and sheep rumen.

    PubMed

    Carro, M D; Ranilla, M J; Martín-García, A I; Molina-Alcaide, E

    2009-04-01

    Eight Rusitec and eight single-flow continuous-culture fermenters (SFCCF) were used to compare the ruminal fermentation of two diets composed of alfalfa hay and concentrate in proportions of 80 : 20 (F80) and 20 : 80 (F20). Results were validated with those obtained previously in sheep fed the same diets. Rusitec fermenters were fed once daily and SFCCF twice, but liquid dilution rates were similar in both types of fermenters. Mean values of pH over the 12 h postfeeding were higher (P < 0.001) in Rusitec than in SFCCF, with diet F80 showing higher values (P < 0.001) in both types of fermenters. Concentrations of total volatile fatty acids (VFA) were higher (P < 0.001) in SFCCF than in Rusitec, and in both systems were higher (P = 0.002) for diet F20 than for diet F80. There were significant differences between systems in the proportions of the main VFA, and a fermentation system × diet interaction (P < 0.001) was detected for all VFA with the exception of valerate. No differences (P = 0.145) between the two types of fermenters were detected in dry matter (DM) digestibility, but NDF, microbial N flow and its efficiency were higher (P = 0.001) in SFCCF compared to Rusitec. Whereas pH values and VFA concentrations remained fairly stable through the day in both in vitro systems, pH dropped and VFA increased shortly after feeding in sheep rumen reaching the minimum and maximal values, respectively, about 4 h after feeding. Both in vitro systems detected differences between diets similar to those found in sheep for liquid dilution rate, pH values, DM digestibility, microbial N flow and growth efficiency. In contrast, acetate/propionate ratios were lower for diet F20 than for F80 in sheep rumen (2.73 and 3.97) and SFCCF (3.07 and 4.80), but were higher for diet F20 compared to F80 (4.29 and 3.40) in Rusitec, with values considered to be unphysiological for high-concentrate diets. In vivo NDF digestibility was affected (P = 0.017) by diet, but no differences between diets

  17. Evaluation of fermentation kinetics of acid-treated corn cob hydrolysate for xylose fermentation in the presence of acetic acid by Pichia stipitis.

    PubMed

    Kashid, Mohan; Ghosalkar, Anand

    2017-08-01

    The efficient utilization of lignocellulosic biomass for ethanol production depends on the fermentability of the biomass hydrolysate obtained after pretreatment. In this work we evaluated the kinetics of ethanol production from xylose using Pichia stipitis in acid-treated corn cob hydrolysate. Acetic acid is one of the main inhibitors in corn cob hydrolysate that negatively impacts kinetics of xylose fermentation by P. stipitis. Unstructured kinetic model has been formulated that describes cell mass growth and ethanol production as a function of xylose, oxygen, ethanol, and acetic acid concentration. Kinetic parameters were estimated under different operating conditions affecting xylose fermentation. This is the first report on kinetics of xylose fermentation by P. stipitis which includes inhibition of acetic acid on growth and product formation. In the presence of acetic acid in the hydrolysate, the model accurately predicted reduction in maximum specific growth rate (from 0.23 to 0.15 h -1 ) and increase in ethanol yield per unit biomass (from 3 to 6.2 gg -1 ), which was also observed during experimental trials. Presence of acetic acid in the fermentation led to significant reduction in the cell growth rate, reduction in xylose consumption and ethanol production rate. The developed model accurately described physiological state of P. stipitis during corn cob hydrolysate fermentation. Proposed model can be used to predict the influence of xylose, ethanol, oxygen, and acetic acid concentration on cell growth and ethanol productivity in industrial fermentation.

  18. The temporal analysis of yeast exponential phase using shotgun proteomics as a fermentation monitoring technique

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Huang, Eric L.; Orsat, Valerie; Shah, Manesh B

    2012-01-01

    System biology and bioprocess technology can be better understood using shotgun proteomics as a monitoring system during the fermentation. We demonstrated a shotgun proteomic method to monitor the temporal yeast proteome in early, middle and late exponential phases. Our study identified a total of 1389 proteins combining all 2D-LC-MS/MS runs. The temporal Saccharomyces cerevisiae proteome was enriched with proteolysis, radical detoxification, translation, one-carbon metabolism, glycolysis and TCA cycle. Heat shock proteins and proteins associated with oxidative stress response were found throughout the exponential phase. The most abundant proteins observed were translation elongation factors, ribosomal proteins, chaperones and glycolytic enzymes. Themore » high abundance of the H-protein of the glycine decarboxylase complex (Gcv3p) indicated the availability of glycine in the environment. We observed differentially expressed proteins and the induced proteins at mid-exponential phase were involved in ribosome biogenesis, mitochondria DNA binding/replication and transcriptional activator. Induction of tryptophan synthase (Trp5p) indicated the abundance of tryptophan during the fermentation. As fermentation progressed toward late exponential phase, a decrease in cell proliferation was implied from the repression of ribosomal proteins, transcription coactivators, methionine aminopeptidase and translation-associated proteins.« less

  19. Biotechnological process for obtaining new fermented products from cashew apple fruit by Saccharomyces cerevisiae strains.

    PubMed

    Araújo, Suzane Macêdo; Silva, Cristina Ferraz; Moreira, Jane Jesus Silveira; Narain, Narendra; Souza, Roberto Rodrigues

    2011-09-01

    In Brazil, the use of cashew apple (Anacardium occidentale L.) to obtain new products by biotechnological process represents an important alternative to avoid wastage of a large quantity of this fruit, which reaches about 85% of the annual production of 1 million tons. This work focuses on the development of an alcoholic product obtained by the fermentation of cashew apple juice. The inoculation with two different strains of yeast Saccharomyces cerevisiae viz. SCP and SCT, were standardized to a concentration of 10(7 )cells ml(-1). Each inoculum was added to 1,500 ml of cashew must. Fermentation was performed at 28 ± 3°C and aliquots were withdrawn every 24 h to monitor soluble sugar concentrations, pH, and dry matter contents. The volatile compounds in fermented products were analyzed using the gas chromatography/mass spectrometry (GC/MS) system. After 6 days, the fermentation process was completed, cells removed by filtration and centrifugation, and the products were stabilized under refrigeration for a period of 20 days. The stabilized products were stored in glass bottles and pasteurized at 60 ± 5°C/30 min. Both fermented products contained ethanol concentration above 6% (v v(-1)) while methanol was not detected and total acidity was below 90 mEq l(-1), representing a pH of 3.8-3.9. The volatile compounds were characterized by the presence of aldehyde (butyl aldehyde diethyl acetal, 2,4-dimethyl-hepta-2,4-dienal, and 2-methyl-2-pentenal) and ester (ethyl α-methylbutyrate) representing fruity aroma. The strain SCT was found to be better and efficient and this produced 10% more alcohol over that of strain SCP.

  20. Addition of grape pomace extract to probiotic fermented goat milk: the effect on phenolic content, probiotic viability and sensory acceptability.

    PubMed

    Dos Santos, Karina Mo; de Oliveira, Isabel C; Lopes, Marcos Ac; Cruz, Ana Paula Gil; Buriti, Flávia Ca; Cabral, Lourdes M

    2017-03-01

    Grape pomace is a source of phenolic compounds, which are associated with health benefits in humans. Additionally, fermented dairy foods with probiotics can be good vehicles to deliver these bioactive compounds. The effects of the addition of grape pomace extract (GPE) on the total phenolic (TP) content, physico-chemical characteristics and viability of Lactobacillus acidophilus LA-5 or Lactobacillus rhamnosus HN001 in fermented goat milks prepared with grape juice were investigated. The TP concentration increased significantly in fermented milks with the addition of GPE. A protective effect of GPE on the viability of L. acidophilus was observed. However, after 14 days of storage, the populations of L. acidophilus were significantly lower when compared with those of L. rhamnosus, and only the last probiotic maintained its viability above 7 log CFU mL -1 throughout the period investigated. The sensory scores of flavor, color and overall acceptability of the fermented milk containing L. rhamnosus HN001 were significantly increased when GPE was added. The use of GPE might increase the functionality of probiotic fermented goat milk processed with L. rhamnosus HN001 and grape juice because grape polyphenols are known for their antioxidant properties and positive effect on the modulation of gut microbiota. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

  1. Comparison of fermented animal feed and mushroom growth media as two value-added options for waste Cassava pulp management.

    PubMed

    Trakulvichean, Sivalee; Chaiprasert, Pawinee; Otmakhova, Julia; Songkasiri, Warinthorn

    2017-12-01

    Cassava is one of the main processed crops in Thailand, but this generates large amounts (7.3 million tons in 2015) of waste cassava pulp (WCP). The solid WCP is sold directly to farmers or pulp-drying companies at a low cost to reduce the burden of on-site waste storage. Using an integrated direct and environmental cost model, fermented animal feed and mushroom growth media were compared as added-value waste management alternatives for WCP to mitigate environmental problems. Primary and secondary data were collected from the literature, field data, and case studies. Data boundaries were restricted to a gate-to-gate scenario with a receiving capacity of 500 t WCP/d, and based on a new production unit being set up at the starch factory. The total production cost of each WCP utilization option was analyzed from the economic and environmental costs. Fermented animal feed was an economically attractive scenario, giving a higher net present value (NPV), lower investment cost and environmental impact, and a shorter payback period for the 10-year operational period. The selling price of mushrooms was the most sensitive parameter regarding the NPV, while the NPV for the price of fermented animal feed had the highest value in the best-case scenario.

  2. Evaluation of the potential use of probiotic strain Lactobacillus plantarum 299v in lactic fermentation of button mushroom fruiting bodies.

    PubMed

    Jabłońska-Ryś, Ewa; Sławińska, Aneta; Radzki, Wojciech; Gustaw, Waldemar

    2016-01-01

    The available literature does not provide data on the application of probiotic strains in mushroom processing. The aim of the study was to evaluate the potential to use the L. plantarum 299v strain with documented probiotic properties in the process of lactic fermentation of button mushroom fruiting bodies (Agaricus bisporus). Fresh button mushroom fruiting bodies and cultures of lactic acid bacteria L. plantarum Ib and a probiotic strain L. plantarum 299v were the material analysed. Sensory evaluation was performed with a 5-point scale, an instrumental method of colour measurement based on the CIA L*a*b* scale, total phenolic compounds were determined with the Folin method, antioxidant properties were assayed with the DPPH radical test, and reducing power was determined using the FRAP method. After a week-long lactic fermentation, the pH value in the samples declined to a level of 3.6 (L. plantarum Ib) and 3.75 (L. plantarum 299v); these values persisted or decreased slightly during the period of maturation of the fermented samples under refrigeration. Fermented mushrooms were assigned high grades in the organoleptic evaluation. The colour analysis revealed significant changes in the values of the L*a*b* parameters in the fermented product, in comparison with fresh mushrooms. Blanching contributed to a significant decrease in the content of total phenolic compounds in the mushroom fruiting bodies and to a decline in antioxidant activity. Mushrooms fermented with the probiotic strain were characterised by higher phenolic compound content and higher antioxidant activity. L. plantarum 299v strain with documented probiotic properties can be applied in fermentation of button mushroom fruiting bodies. Products obtained with the use of both strains were characterised by good sensory properties. The type of strain used in the lactic fermentation of mushroom fruiting bodies had an effect on the phenolic compound content and antioxidant properties of the final product.

  3. Alcoholic fermentation induces melatonin synthesis in orange juice.

    PubMed

    Fernández-Pachón, M S; Medina, S; Herrero-Martín, G; Cerrillo, I; Berná, G; Escudero-López, B; Ferreres, F; Martín, F; García-Parrilla, M C; Gil-Izquierdo, A

    2014-01-01

    Melatonin (N-acetyl-5-methoxytryptamine) is a molecule implicated in multiple biological functions. Its level decreases with age, and the intake of foods rich in melatonin has been considered an exogenous source of this important agent. Orange is a natural source of melatonin. Melatonin synthesis occurs during alcoholic fermentation of grapes, malt and pomegranate. The amino acid tryptophan is the precursor of all 5-methoxytryptamines. Indeed, melatonin appears in a shorter time in wines when tryptophan is added before fermentation. The aim of the study was to measure melatonin content during alcoholic fermentation of orange juice and to evaluate the role of the precursor tryptophan. Identification and quantification of melatonin during the alcoholic fermentation of orange juice was carried out by UHPLC-QqQ-MS/MS. Melatonin significantly increased throughout fermentation from day 0 (3.15 ng/mL) until day 15 (21.80 ng/mL) reaching larger amounts with respect to other foods. Melatonin isomer was also analysed, but its content remained stable ranging from 11.59 to 14.18 ng/mL. The enhancement of melatonin occurred mainly in the soluble fraction. Tryptophan levels significantly dropped from 13.80 mg/L (day 0) up to 3.19 mg/L (day 15) during fermentation. Melatonin was inversely and significantly correlated with tryptophan (r = 0.907). Therefore, the enhancement in melatonin could be due to both the occurrence of tryptophan and the new synthesis by yeast. In summary, the enhancement of melatonin in novel fermented orange beverage would improve the health benefits of orange juice by increasing this bioactive compound. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  4. Metaproteomics of Microbiota in Naturally Fermented Soybean Paste, Da-jiang.

    PubMed

    Zhang, Ping; Zhang, Pengfei; Xie, Mengxi; An, Feiyu; Qiu, Boshu; Wu, Rina

    2018-05-01

    Da-jiang is a typical traditional fermented soybean product in China. At present, the proteins in da-jiang are needed to be explored. The composition and species of microbial proteins in traditional fermented da-jiang were analyzed by metaproteomics based on sodium dodecyl sulfonate-polyacrylamide gel electrophoresis (SDS-PAGE) and liquid chromatography-mass spectrometry/mass spectrometry (LC-MS/MS). The results showed that the number and variety of microbial proteins in the traditional fermented da-jiang from different regions were different. The production site influences the fermentation in da-jiang. Then we analyzed the functions of the microbial proteins identified in da-jiang, and found that they were mainly involved in the process of protein synthesis, glycometabolism and nucleic acid synthesis. In addtion, we compared the proteins composition in different da-jiang. There are 51 common proteins of naturally fermented da-jiang, and 25 common microbial sources. The main commonly microbial sources of fungal proteins are Saccharomyces cerevisiae and Schizosaccharomyces; the main commonly microbial sources of bacterial proteins are Enterococcus faecalis, Leuconostoc mesenteroides, Acinetobacter baumannii, and Bacillus subtilis. These common microbes play the predominant role in da-jiang fermentation. The present results help us to understand the fermentation of da-jiang and improve the quality and safety of final products in the future. The study illustrated metaproteome of microbiota in traditional fermented soybean paste, da-jiang, by sodium dodecyl sulfonate-polyacrylamide gel electrophoresis (SDS-PAGE) and liquid chromatography-mass spectrometry/mass spectrometry (LC-MS/MS). A method of extracting metaproteome from microbiota in da-jiang was attempted. The findings help to understand the fermentation of da-jiang and improve the quality and safety of da-jiang in fermented industry. © 2018 Institute of Food Technologists®.

  5. Species diversity, community dynamics, and metabolite kinetics of spontaneous leek fermentations.

    PubMed

    Wouters, D; Bernaert, N; Conjaerts, W; Van Droogenbroeck, B; De Loose, M; De Vuyst, L

    2013-04-01

    Leek (Allium ampeloprasum var. porrum) is one of Belgium's most important vegetables. All or part of the green leek parts are often left on the fields because of their limited cooking applications compared to the white leek parts. Therefore, the possibility to perform leek fermentations in view of product valorization and diversification was investigated. This study deals with the community dynamics, species diversity, and metabolite kinetics of spontaneous leek fermentations, thereby studying the influence of added NaCl concentration, harvesting season, and duration of the fermentation. The combination of a culture-dependent and culture-independent approach revealed the prevalence of lactic acid bacteria (LAB) from the third day of fermentation onwards, which was not influenced by the fermentation conditions applied. Enterobacteriaceae, Pseudomonadaceae, and yeasts disappeared after one week of fermentation. Leuconostoc mesenteroides, Lactobacillus sakei, and Lactobacillus plantarum, Lactobacillus brevis, and Lactobacillus parabrevis were the most frequently isolated LAB species. Both added NaCl concentrations were suitable to perform successful fermentations within three weeks. By that time, glucose and fructose, the main leek carbohydrates, were metabolized into mainly lactic acid, acetic acid, ethanol, and mannitol. A sensory analysis revealed that the fermented white leek parts were generally more appreciated than the fermented green leek parts. Copyright © 2012 Elsevier Ltd. All rights reserved.

  6. Membrane-mediated extractive fermentation for lactic acid production from cellulosic biomass

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Chen, Rongfu; Lee, Y.Y.

    1997-12-31

    Lactic acid production from cellulosic biomass by cellulose and Lactobacillus delbrueckii was studied in a fermenter-extractor employing a microporous hollow fiber membrane (NIHF). This bioreactor system was operated under a fed-batch mode with continuous removal of lactic acid by an in situ extraction. A tertiary amine (Alamine 336) was used as an extractant for lactic acid. The extraction capacity of Alamine 336 is greatly enhanced by addition of alcohol. Long-chain alcohols serve well for this purpose since they are less toxic to micro-organism. Addition of kerosene, a diluent, was necessary to reduce the solvent viscosity. A solvent mixture of 20%more » Alamine 336,40% oleyl alcohol, and 40% kerosene was found to be most effective in the extraction of lactic acid. Progressive change of pH from an initial value of 5.0 down to 4.3 has significantly improved the overall performance of the simultaneous saccharification and extractive fermentation over that of constant pH operation. The change of pH was applied to promote cell growth in the early phase, and extraction in the latter phase. 20 refs., 10 figs., 1 tab.« less

  7. Physical and Sensory Properties of Ice Cream Containing Fermented Pepper Powder

    PubMed Central

    Kim, Soo-Ki; Seo, Han-Geuk

    2017-01-01

    This study was conducted to investigate the physical and sensory properties of ice cream containing fermented pepper powder. Three ice cream formulas were manufactured: 1, control; 2, supplemented with 0.1% fermented pepper powder; and 3, supplemented with 0.2% fermented pepper powder. Formulas 2 and 3 had significantly higher viscosity and lower overrun than formula 1 (p<0.05). Additionally, ice creams supplemented with fermented pepper powder were harder and maintained their forms longer than the controls. 0.2% fermented pepper powder added ice cream had no pungency as much as that of control and overall sensory attribute was not significantly different from control. Therefore, ice cream containing fermented pepper powder maintained physical and sensory properties similar to the controls, and maintenance was better. It means fermented pepper powder ice cream can be utilized as the material of functional food (dessert). PMID:28316469

  8. Comparative studies on the fermentation performance of autochthonous Saccharomyces cerevisiae strains in Chinese light-fragrant liquor during solid-state or submerged fermentation.

    PubMed

    Kong, Y; Wu, Q; Xu, Y

    2017-04-01

    To explore the metabolic characteristic of autochthonous Saccharomyces cerevisiae strains in Chinese light-fragrant liquor fermentation. Inter-delta amplification analysis was used to differentiate the S. cerevisiae strains at strain level. Twelve biotypes (I-XII) were identified among the 72 S. cerevisiae strains preselected. A comparison was conducted between solid-state fermentation (SSF) and submerged fermentation (SmF) with S. cerevisiae strains had different genotype, with a focus on the production of ethanol and the volatile compounds. The degree of ethanol ranged from 28·0 to 45·2 g l -1 in SmF and from 14·8 to 25·6 g kg -1 in SSF, and SSF was found to be more suitable for the production of ethanol with higher yield coefficient of all the S. cerevisiae strains. The metabolite profiles of each yeast strain showed obvious distinction in the two fermentations. The highest amounts of ethyl acetate in SmF and SSF were found in genotype VII (328·2 μg l -1 ) and genotype V (672 μg kg -1 ), respectively. In addition, the generation of some volatile compounds could be strictly related to the strain used. Compound β-damascenone was only detected in genotypes I, II, X and XII in the two fermentation processes. Furthermore, laboratory scale fermentations were clearly divided into SSF and SmF in hierarchical cluster analysis regardless of the inoculated yeast strains, indicating that the mode of fermentation was more important than the yeast strains inoculated. The autochthonous S. cerevisiae strains in Chinese light-fragrant liquor vary considerably in terms of their volatiles profiles during SSF and SmF. This work facilitates a better understanding of the fermentative mechanism in the SSF process for light-fragrant liquor production. © 2016 The Society for Applied Microbiology.

  9. Control and prediction of the course of brewery fermentations by gravimetric analysis.

    PubMed

    Kosín, P; Savel, J; Broz, A; Sigler, K

    2008-01-01

    A simple, fast and cheap test suitable for predicting the course of brewery fermentations based on mass analysis is described and its efficiency is evaluated. Compared to commonly used yeast vitality tests, this analysis takes into account wort composition and other factors that influence fermentation performance. It can be used to predict the shape of the fermentation curve in brewery fermentations and in research and development projects concerning yeast vitality, fermentation conditions and wort composition. It can also be a useful tool for homebrewers to control their fermentations.

  10. Biomass Content Governs Fermentation Rate in Nitrogen-Deficient Wine Musts

    PubMed Central

    Varela, Cristian; Pizarro, Francisco; Agosin, Eduardo

    2004-01-01

    Problematic fermentations are common in the wine industry. Assimilable nitrogen deficiency is the most prevalent cause of sluggish fermentations and can reduce fermentation rates significantly. A lack of nitrogen diminishes a yeast's metabolic activity, as well as the biomass yield, although it has not been clear which of these two interdependent factors is more significant in sluggish fermentations. Under winemaking conditions with different initial nitrogen concentrations, metabolic flux analysis was used to isolate the effects. We quantified yeast physiology and identified key metabolic fluxes. We also performed cell concentration experiments to establish how biomass yield affects the fermentation rate. Intracellular analysis showed that trehalose accumulation, which is highly correlated with ethanol production, could be responsible for sustaining cell viability in nitrogen-poor musts independent of the initial assimilable nitrogen content. Other than the higher initial maintenance costs in sluggish fermentations, the main difference between normal and sluggish fermentations was that the metabolic flux distributions in nitrogen-deficient cultures revealed that the specific sugar uptake rate was substantially lower. The results of cell concentration experiments, however, showed that in spite of lower sugar uptake, adding biomass from sluggish cultures not only reduced the time to finish a problematic fermentation but also was less likely to affect the quality of the resulting wine as it did not alter the chemistry of the must. PMID:15184136

  11. Physicochemical and Microbial Properties of the Korean Traditional Rice Wine, Makgeolli, Supplemented with Banana during Fermentation.

    PubMed

    Kim, Eunkyung; Chang, Yoon Hyuk; Ko, Jae Youn; Jeong, Yoonhwa

    2013-09-01

    The objective of the present study was to evaluate the physicochemical and microbial properties of the Korean traditional rice wine Makgeolli, supplemented with banana during 6 day fermentation. The alcohol contents of the control and banana Makgeolli were 17.0 and 16.5%, respectively. The pH values decreased while total acidity, total soluble solids, and color values increased throughout the fermentation process. An increase in microorganism counts throughout the 6-day fermentation period was noted in all samples. The major free sugar and organic acid detected in all samples were glucose and succinic acid, respectively. There were 39 volatile compounds detected in the control and banana Makgeolli. The major ester detected was ethyl acetate (20.037 and 22.604% for the control and banana Makgeolli, respectively). The major alcohol compounds detected were 3-methylbutanol (20.933%) and 3-methyl-1-butanol (34.325%) in the control. 2-mtehyl-1-propanol (22.289%) and 3-methyl-1-butanol (39.851%) were the highest alcohol compounds detected in the banana Makgeolli.

  12. Physicochemical and Microbial Properties of the Korean Traditional Rice Wine, Makgeolli, Supplemented with Banana during Fermentation

    PubMed Central

    Kim, Eunkyung; Chang, Yoon Hyuk; Ko, Jae Youn; Jeong, Yoonhwa

    2013-01-01

    The objective of the present study was to evaluate the physicochemical and microbial properties of the Korean traditional rice wine Makgeolli, supplemented with banana during 6 day fermentation. The alcohol contents of the control and banana Makgeolli were 17.0 and 16.5%, respectively. The pH values decreased while total acidity, total soluble solids, and color values increased throughout the fermentation process. An increase in microorganism counts throughout the 6-day fermentation period was noted in all samples. The major free sugar and organic acid detected in all samples were glucose and succinic acid, respectively. There were 39 volatile compounds detected in the control and banana Makgeolli. The major ester detected was ethyl acetate (20.037 and 22.604% for the control and banana Makgeolli, respectively). The major alcohol compounds detected were 3-methylbutanol (20.933%) and 3-methyl-1-butanol (34.325%) in the control. 2-mtehyl-1-propanol (22.289%) and 3-methyl-1-butanol (39.851%) were the highest alcohol compounds detected in the banana Makgeolli. PMID:24471133

  13. Relevance of microbial coculture fermentations in biotechnology.

    PubMed

    Bader, J; Mast-Gerlach, E; Popović, M K; Bajpai, R; Stahl, U

    2010-08-01

    The purpose of this article is to review coculture fermentations in industrial biotechnology. Examples for the advantageous utilization of cocultures instead of single cultivations include the production of bulk chemicals, enzymes, food additives, antimicrobial substances and microbial fuel cells. Coculture fermentations may result in increased yield, improved control of product qualities and the possibility of utilizing cheaper substrates. Cocultivation of different micro-organisms may also help to identify and develop new biotechnological substances. The relevance of coculture fermentations and the potential of improving existing processes as well as the production of new chemical compounds in industrial biotechnology are pointed out here by means of more than 35 examples.

  14. The Preboreal-like Asian monsoon climate in the early last interglacial period recorded from the Dark Cave, Southwest China

    NASA Astrophysics Data System (ADS)

    Jiang, Xiuyang; He, Yaoqi; Wang, Xiaoyan; Sun, Xiaoshuang; Hong, Hui; Liu, Juan; Yu, Tsai-Luen; Li, Zhizhong; Shen, Chuan-Chou

    2017-08-01

    Transitions of glacial-interglacial cycles are critical periods for Quaternary climate shifts. Here, we present new, decadal resolution Asian summer monsoon (ASM) record from three stalagmites obtained from the Dark Cave in southwestern China over 130-114 thousand years ago (ka, before CE 1950). Chronology was anchored by 28 230Th dates with typical uncertainties of ±0.3-1.0 kyr, allowing an assessment of timing and transition of climate changes during the onset and end of the last interglacial. An agreement between this new and previous stalagmite δ18O records supports that summer insolation predominates orbital-scale ASM evolution. A 2-3 kyr-long gradually increasing ASM period, analogous to the classical Preboreal episode in the early Holocene, follows the termination of a weak monsoon interval at 129.0 ± 0.8 ka. This finding suggests a strong influence of high-latitude ice-sheet dynamics on Asian monsoonal conditions during the early interglacial period. An abrupt end of the marine isotope stage 5e at 118.8 ± 0.6 ka was probably caused by the internal climate system threshold effects.

  15. Genetic improvement of native xylose-fermenting yeasts for ethanol production.

    PubMed

    Harner, Nicole K; Wen, Xin; Bajwa, Paramjit K; Austin, Glen D; Ho, Chi-Yip; Habash, Marc B; Trevors, Jack T; Lee, Hung

    2015-01-01

    Lignocellulosic substrates are the largest source of fermentable sugars for bioconversion to fuel ethanol and other valuable compounds. To improve the economics of biomass conversion, it is essential that all sugars in potential hydrolysates be converted efficiently into the desired product(s). While hexoses are fermented into ethanol and some high-value chemicals, the bioconversion of pentoses in hydrolysates remains inefficient. This remains one of the key challenges in lignocellulosic biomass conversion. Native pentose-fermenting yeasts can ferment both glucose and xylose in lignocellulosic biomass to ethanol. However, they perform poorly in the presence of hydrolysate inhibitors, exhibit low ethanol tolerance and glucose repression, and ferment pentoses less efficiently than the main hexoses glucose and mannose. This paper reviews classical and molecular strain improvement strategies applied to native pentose-fermenting yeasts for improved ethanol production from xylose and lignocellulosic substrates. We focus on Pachysolen tannophilus, Scheffersomyces (Candida) shehatae, Scheffersomyces (Pichia) stipitis, and Spathaspora passalidarum which are good ethanol producers among the native xylose-fermenting yeasts. Strains obtained thus far are not robust enough for efficient ethanol production from lignocellulosic hydrolysates and can benefit from further improvements.

  16. Effect of osmotic dehydration of olives as pre-fermentation treatment and partial substitution of sodium chloride by monosodium glutamate in the fermentation profile of Kalamata natural black olives.

    PubMed

    Bonatsou, Stamatoula; Iliopoulos, Vasilis; Mallouchos, Athanasios; Gogou, Eleni; Oikonomopoulou, Vasiliki; Krokida, Magdalini; Taoukis, Petros; Panagou, Efstathios Z

    2017-05-01

    This study examined the effect of osmotic dehydration of Kalamata natural black olives as pre-fermentation treatment in combination with partial substitution of NaCl by monosodium glutamate (MSG) on the fermentation profile of olives. Osmotic dehydration was undertaken by immersing the olives in 70% (w/w) glucose syrup overnight at room temperature. Further on, three different mixtures of NaCl and MSG with/without prior osmotic dehydration of olives were investigated, namely (i) 6.65% NaCl - 0.35% MSG (5% substitution), (ii) 6.30% NaCl - 0.70% MSG (10% substitution), (iii) 5.95% NaCl - 1.05% MSG (15% substitution), and (iv) 7% NaCl without osmotic dehydration (control treatment). Changes in the microbial association (lactic acid bacteria [LAB], yeasts, Enterobacteriaceae), pH, titratable acidity, organic acids, sugars, and volatile compounds in the brine were analyzed for a period of 4 months. The final product was subjected to sensory analysis and the content of MSG in olives was determined. Results demonstrated that osmotic dehydration of olives prior to brining led to vigorous lactic acid processes as indicated by the obtained values of pH (3.7-4.1) and acidity (0.7-0.8%) regardless of the amount of MSG used. However, in non-osmotically dehydrated olives, the highest substitution level of MSG resulted in a final pH (4.5) that was beyond specification for this type of olives. MSG was degraded in the brines being almost completely converted to γ-aminobutyric acid (GABA) at the end of fermentation. Finally, the sensory assessment of fermented olives with/without osmotic dehydration and at all levels of MSG did not show any deviation compared to the control treatment. Copyright © 2016 Elsevier Ltd. All rights reserved.

  17. Enhanced ethanol fermentation by engineered Saccharomyces cerevisiae strains with high spermidine contents.

    PubMed

    Kim, Sun-Ki; Jo, Jung-Hyun; Jin, Yong-Su; Seo, Jin-Ho

    2017-05-01

    Construction of robust and efficient yeast strains is a prerequisite for commercializing a biofuel production process. We have demonstrated that high intracellular spermidine (SPD) contents in Saccharomyces cerevisiae can lead to improved tolerance against various fermentation inhibitors, including furan derivatives and acetic acid. In this study, we examined the potential applicability of the S. cerevisiae strains with high SPD contents under two cases of ethanol fermentation: glucose fermentation in repeated-batch fermentations and xylose fermentation in the presence of fermentation inhibitors. During the sixteen times of repeated-batch fermentations using glucose as a sole carbon source, the S. cerevisiae strains with high SPD contents maintained higher cell viability and ethanol productivities than a control strain with lower SPD contents. Specifically, at the sixteenth fermentation, the ethanol productivity of a S. cerevisiae strain with twofold higher SPD content was 31% higher than that of the control strain. When the SPD content was elevated in an engineered S. cerevisiae capable of fermenting xylose, the resulting S. cerevisiae strain exhibited much 40-50% higher ethanol productivities than the control strain during the fermentations of synthetic hydrolysate containing high concentrations of fermentation inhibitors. These results suggest that the strain engineering strategy to increase SPD content is broadly applicable for engineering yeast strains for robust and efficient production of ethanol.

  18. [Intrauterine devices in the immediate, early and late postabortion period].

    PubMed

    Nun, S

    1971-01-01

    2146 cases of IUD insertions after hospitalization for abortion at a hospital in Chile were studied. In 1514 cases the IUDs were inserted immediately after abortion, in 430 cases between 1-5 days after the operation, and in 202 cases between 5-40 days after. It is concluded that immediate or early insertion results in a somewhat lower retention rate, but offers the advantage of making it possible to treat a greater number of patients, many of whom would not return later to have the IUD inserted. The incidence of removal for medical causes was very low and immediate insertion was found to be harmless. The medical causes of removal were the usual ones of bleeding, pain, and infection; the most frequent cause of interruption of use was expulsion, which tends to occur during the 1st few months of use and among younger women. The probability of failure due to pregnancy was somewhat higher than in the case of insertion during the intermenstrual period. Cases of voluntary removal tend to increase after prolonged use, and a study to analyze the actual reasons for this fact is necessary.

  19. Influence of fiber degradation and concentration of fermentable sugars on simultaneous saccharification and fermentation of high-solids spruce slurry to ethanol.

    PubMed

    Hoyer, Kerstin; Galbe, Mats; Zacchi, Guido

    2013-10-08

    Saccharification and fermentation of pretreated lignocellulosic materials, such as spruce, should be performed at high solids contents in order to reduce the cost of the produced bioethanol. However, this has been shown to result in reduced ethanol yields or a complete lack of ethanol production. Previous studies have shown inconsistent results when prehydrolysis is performed at a higher temperature prior to the simultaneous saccharification and fermentation (SSF) of steam-pretreated lignocellulosic materials. In some cases, a significant increase in overall ethanol yield was reported, while in others, a slight decrease in ethanol yield was observed. In order to investigate the influence of prehydrolysis on high-solids SSF of steam-pretreated spruce slurry, in the present study, the presence of fibers and inhibitors, degree of fiber degradation and initial fermentable sugar concentration has been studied. SSF of whole steam-pretreated spruce slurry at a solids content of 13.7% water-insoluble solids (WIS) resulted in a very low overall ethanol yield, mostly due to poor fermentation. The yeast was, however, able to ferment the washed slurry and the liquid fraction of the pretreated slurry. Performing prehydrolysis at 48°C for 22 hours prior to SSF of the whole pretreated slurry increased the overall ethanol yield from 3.9 to 62.1%. The initial concentration of fermentable sugars in SSF could not explain the increase in ethanol yield in SSF with prehydrolysis. Although the viscosity of the material did not appear to decrease significantly during prehydrolysis, the degradation of the fibers prior to the addition of the yeast had a positive effect on ethanol yield when using whole steam-pretreated spruce slurry. The results of the present study suggest that the increase in ethanol yield from SSF when performing prehydrolysis is a result of fiber degradation rather than a decrease in viscosity. The increased concentration of fermentable sugars at the beginning of the

  20. Single Zymomonas mobilis strain for xylose and arabinose fermentation

    DOEpatents

    Zhang, M.; Chou, Y.C.; Picataggio, S.K.; Finkelstein, M.

    1998-12-01

    This invention relates to single microorganisms which normally do not ferment pentose sugars which are genetically altered to ferment the pentose sugars, xylose and arabinose, to produce ethanol, and a fermentation process utilizing the same. Examples include Zymomonas mobilis which has been transformed with a combination of E. coli genes for xylose isomerase, xylulokinase, L-arabinose isomerase, L-ribulokinase, L-ribulose 5-phosphate 4-epimerase, transaldolase and transketolase. Expression of added genes are under the control of Z. mobilis promoters. These newly created microorganisms are useful for fermenting glucose, xylose and arabinose, produced by hydrolysis of hemicellulose and cellulose or starch, to produce ethanol. 6 figs.