Sample records for acid production potential

  1. Potential of Different Coleus blumei Tissues for Rosmarinic Acid Production

    PubMed Central

    Vuković, Rosemary; Likić, Saša; Jelaska, Sibila

    2015-01-01

    Summary Rosmarinic acid is one of the main active components of Coleus blumei and is known to have numerous health benefits. The pharmacological significance of rosmarinic acid and its production through in vitro culture has been the subject of numerous studies. Here, the ability of different tissues to accumulate rosmarinic acid and sustainability in production over long cultivation have been tested. Calli, tumours, normal roots and hairy roots were established routinely by application of plant growth regulators or by transformation with agrobacteria. The differences among the established tumour lines were highly heterogeneous. Hairy root lines showed the highest mean growth rate and consistency in rosmarinic acid production. Although some tumour lines produced more rosmarinic acid than the hairy root lines, over a long cultivation period their productivity was unstable and decreased. Further, the effects of plant growth regulators on growth and rosmarinic acid accumulation were tested. 2,4-Dichlorophenoxyacetic acid significantly reduced tumour growth and rosmarinic acid production. 1-Naphthaleneacetic acid strongly stimulated hairy root growth whilst abscisic acid strongly enhanced rosmarinic acid production. Hairy roots cultured in an airlift bioreactor exhibited the highest potential for mass production of rosmarinic acid. PMID:27904326

  2. Natural products as potential anticonvulsants: caffeoylquinic acids.

    PubMed

    Kim, Hyo Geun; Oh, Myung Sook

    2012-03-01

    Current anticonvulsant therapies are generally directed at symptomatic treatment by suppressing excitability within the brain. Consequently, they have adverse effects such as cognitive impairment, dependence, and abuse. The need for more effective and less toxic anticonvulsants has generated renewed interest in natural products for the treatment of convulsions. Caffeoylquinic acids (CQs) are naturally occurring phenolic acids that are distributed widely in plants. There has been increasing interest in the biological activities of CQs in diseases of the central nervous system. In this issue, Nugroho et al. give evidence for the anticonvulsive effect of a CQ-rich extract from Aster glehni Franchet et Sckmidt. They optimized the extract solvent conditions, resulting in high levels of CQs and peroxynitrite-scavenging activity. Then, they investigated the sedative and anticonvulsive effects in pentobarbital- and pentylenetetrazole-induced models in mice. The CQ-rich extract significantly inhibited tonic convulsions as assessed by onset time, tonic extent, and mortality. They suggested that the CQ-rich extract from A. glehni has potential for treating convulsions. This report provides preclinical data which may be used for the development of anticonvulsants from natural products.

  3. Acid Lipase from Candida viswanathii: Production, Biochemical Properties, and Potential Application

    PubMed Central

    de Almeida, Alex Fernando; Carmona, Eleonora Cano

    2013-01-01

    Influences of environmental variables and emulsifiers on lipase production of a Candida viswanathii strain were investigated. The highest lipase activity (101.1 U) was observed at 210 rpm, pH 6.0, and 27.5°C. Other fermentation parameters analyzed showed considerable rates of biomass yield (Y L/S = 1.381 g/g), lipase yield (Y L/S = 6.892 U/g), and biomass productivity (P X = 0.282 g/h). Addition of soybean lecithin increased lipase production in 1.45-fold, presenting lipase yield (Y L/S) of 10.061 U/g. Crude lipase presented optimal activity at acid pH of 3.5, suggesting a new lipolytic enzyme for this genus and yeast in general. In addition, crude lipase presented high stability in acid conditions and temperature between 40 and 45°C, after 24 h of incubation in these temperatures. Lipase remained active in the presence of organic solvents maintaining above 80% activity in DMSO, methanol, acetonitrile, ethanol, acetone, 1-propanol, isopropanol, and 2-propanol. Effectiveness for the hydrolysis of a wide range of natural triglycerides suggests that this new acid lipase has high potential application in the oleochemical and food industries for hydrolysis and/or modification of triacylglycerols to improve the nutritional properties. PMID:24350270

  4. Bacterial production of short-chain organic acids and trehalose from levulinic acid: a potential cellulose-derived building block as a feedstock for microbial production.

    PubMed

    Habe, Hiroshi; Sato, Shun; Morita, Tomotake; Fukuoka, Tokuma; Kirimura, Kohtaro; Kitamoto, Dai

    2015-02-01

    Levulinic acid (LA) is a platform chemical derived from cellulosic biomass, and the expansion of LA utilization as a feedstock is important for production of a wide variety of chemicals. To investigate the potential of LA as a substrate for microbial conversion to chemicals, we isolated and identified LA-utilizing bacteria. Among the six isolated strains, Pseudomonas sp. LA18T and Rhodococcus hoagie LA6W degraded up to 70 g/L LA in a high-cell-density system. The maximal accumulation of acetic acid by strain LA18T and propionic acid by strain LA6W was 13.6 g/L and 9.1 g/L, respectively, after a 4-day incubation. Another isolate, Burkholderia stabilis LA20W, produced trehalose extracellularly in the presence of 40 g/L LA to approximately 2 g/L. These abilities to produce useful compounds supported the potential of microbial LA conversion for future development and cellulosic biomass utilization. Copyright © 2014 Elsevier Ltd. All rights reserved.

  5. Oral hygiene products and acidic medicines.

    PubMed

    Hellwig, E; Lussi, A

    2006-01-01

    Acidic or EDTA-containing oral hygiene products and acidic medicines have the potential to soften dental hard tissues. The low pH of oral care products increases the chemical stability of some fluoride compounds, favors the incorporation of fluoride ions in the lattice of hydroxyapatite and the precipitation of calcium fluoride on the tooth surface. This layer has some protective effect against an erosive attack. However, when the pH is too low or when no fluoride is present these protecting effects are replaced by direct softening of the tooth surface. Xerostomia or oral dryness can occur as a consequence of medication such as tranquilizers, anti-histamines, anti-emetics and anti-parkinsonian medicaments or of salivary gland dysfunction e.g. due to radiotherapy of the oral cavity and the head and neck region. Above all, these patients should be aware of the potential demineralization effects of oral hygiene products with low pH and high titratable acids. Acetyl salicylic acid taken regularly in the form of multiple chewable tablets or in the form of headache powder as well chewing hydrochloric acids tablets for treatment of stomach disorders can cause erosion. There is most probably no direct association between asthmatic drugs and erosion on the population level. Consumers, patients and health professionals should be aware of the potential of tooth damage not only by oral hygiene products and salivary substitutes but also by chewable and effervescent tablets. Additionally, it can be assumed that patients suffering from xerostomia should be aware of the potential effects of oral hygiene products with low pH and high titratable acids.

  6. 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.

  7. Organic Acid Production by Filamentous Fungi

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

    Magnuson, Jon K.; Lasure, Linda L.

    Many of the commercial production processes for organic acids are excellent examples of fungal biotechnology. However, unlike penicillin, the organic acids have had a less visible impact on human well-being. Indeed, organic acid fermentations are often not even identified as fungal bioprocesses, having been overshadowed by the successful deployment of the β-lactam processes. Yet, in terms of productivity, fungal organic acid processes may be the best examples of all. For example, commercial processes using Aspergillus niger in aerated stirred-tank-reactors can convert glucose to citric acid with greater than 80% efficiency and at final concentrations in hundreds of grams per liter.more » Surprisingly, this phenomenal productivity has been the object of relatively few research programs. Perhaps a greater understanding of this extraordinary capacity of filamentous fungi to produce organic acids in high concentrations will allow greater exploitation of these organisms via application of new knowledge in this era of genomics-based biotechnology. In this chapter, we will explore the biochemistry and modern genetic aspects of the current and potential commercial processes for making organic acids. The organisms involved, with a few exceptions, are filamentous fungi, and this review is limited to that group. Although yeasts including Saccharomyces cerevisiae, species of Rhodotorula, Pichia, and Hansenula are important organisms in fungal biotechnology, they have not been significant for commercial organic acid production, with one exception. The yeast, Yarrowia lipolytica, and related yeast species, may be in use commercially to produce citric acid (Lopez-Garcia, 2002). Furthermore, in the near future engineered yeasts may provide new commercial processes to make lactic acid (Porro, Bianchi, Ranzi, Frontali, Vai, Winkler, & Alberghina, 2002). This chapter is divided into two parts. The first contains a review of the commercial aspects of current and potential large

  8. Significance of pH on the Cytotoxic Potential of the Water Disinfection By-Product Iodoacetic Acid

    EPA Science Inventory

    Significance of pH on the Cytotoxic Potential of the Water Disinfection By-Product Iodoacetic Acid Vicki Richardson1, Susan D. Richardson2, Mary Moyer3, Jane Ellen Simmons1, and Anthony DeAngelo1, 1U.S. Environmental Protection Agency, Research Triangle Park, NC, 2University of...

  9. Studies on potential effects of fumaric acid on rumen microbial fermentation, methane production and microbial community.

    PubMed

    Riede, Susanne; Boguhn, Jeannette; Breves, Gerhard

    2013-01-01

    The greenhouse gas methane (CH4) contributes substantially to global climate change. As a potential approach to decrease ruminal methanogenesis, the effects of different dosages of fumaric acid (FA) on ruminal microbial metabolism and on the microbial community (archaea, bacteria) were studied using a rumen simulation technique (RUSITEC). FA acts as alternative hydrogen acceptor diverting 2H from methanogenesis of archaea towards propionate formation of bacteria. Three identical trials were conducted with 12 fermentation vessels over a period of 14 days. In each trial, four fermentation vessels were assigned to one of the three treatment groups differing in FA dosage: low fumaric acid (LFA), high fumaric acid (HFA) and without FA (control). FA was continuously infused with the buffer. Grass silage and concentrate served as substrate. FA led to decreases in pH and to higher production rates of total short chain fatty acids (SCFA) mediated by increases in propionate for LFA of 1.69 mmol d(-1) and in propionate and acetate production for HFA of 4.49 and 1.10 mmol d(-1), respectively. Concentrations of NH3-N, microbial crude protein synthesis, their efficiency, degradation of crude nutrients and detergent fibre fraction were unchanged. Total gas and CH4 production were not affected by FA. Effects of FA on structure of microbial community by means of single strand conformation polymorphism (SSCP) analyses could not be detected. Given the observed increase in propionate production and the unaffected CH4 production it can be supposed that the availability of reduction equivalents like 2H was not limited by the addition of FA in this study. It has to be concluded from the present study that the application of FA is not an appropriate approach to decrease the ruminal CH4 production.

  10. Biotechnological Production of Organic Acids from Renewable Resources.

    PubMed

    Pleissner, Daniel; Dietz, Donna; van Duuren, Jozef Bernhard Johann Henri; Wittmann, Christoph; Yang, Xiaofeng; Lin, Carol Sze Ki; Venus, Joachim

    2017-03-07

    Biotechnological processes are promising alternatives to petrochemical routes for overcoming the challenges of resource depletion in the future in a sustainable way. The strategies of white biotechnology allow the utilization of inexpensive and renewable resources for the production of a broad range of bio-based compounds. Renewable resources, such as agricultural residues or residues from food production, are produced in large amounts have been shown to be promising carbon and/or nitrogen sources. This chapter focuses on the biotechnological production of lactic acid, acrylic acid, succinic acid, muconic acid, and lactobionic acid from renewable residues, these products being used as monomers for bio-based material and/or as food supplements. These five acids have high economic values and the potential to overcome the "valley of death" between laboratory/pilot scale and commercial/industrial scale. This chapter also provides an overview of the production strategies, including microbial strain development, used to convert renewable resources into value-added products.

  11. Bacteriocins from lactic acid bacteria and their potential in the preservation of fruit products.

    PubMed

    Barbosa, Ana Andréa Teixeira; Mantovani, Hilário Cuquetto; Jain, Sona

    2017-11-01

    Bacteriocins produced by lactic acid bacteria (LAB) are well-recognized for their potential as natural food preservatives. These antimicrobial peptides usually do not change the sensorial properties of food products and can be used in combination with traditional preservation methods to ensure microbial stability. In recent years, fruit products are increasingly being associated with food-borne pathogens and spoilage microorganisms, and bacteriocins are important candidates to preserve these products. Bacteriocins have been extensively studied to preserve foods of animal origin. However, little information is available for their use in vegetable products, especially in minimally processed ready-to-eat fruits. Although, many bacteriocins possess useful characteristics that can be used to preserve fruit products, to date, only nisin, enterocin AS-48, bovicin HC5, enterocin 416K1, pediocin and bificin C6165 have been tested for their activity against spoilage and pathogenic microorganisms in these products. Among these, only nisin and pediocin are approved to be commercially used as food additives, and their use in fruit products is still limited to certain countries. Considering the increasing demand for fresh-tasting fruit products and concern for public safety, the study of other bacteriocins with biochemical characteristics that make them candidates for the preservation of these products are of great interest. Efforts for their approval as food additives are also important. In this review, we discuss why the study of bacteriocins as an alternative method to preserve fruit products is important; we detail the biotechnological approaches for the use of bacteriocins in fruit products; and describe some bacteriocins that have been tested and have potential to be tested for the preservation of fruit products.

  12. The investigation of probiotic potential of lactic acid bacteria isolated from traditional Mongolian dairy products.

    PubMed

    Takeda, Shiro; Yamasaki, Keiko; Takeshita, Masahiko; Kikuchi, Yukiharu; Tsend-Ayush, Chuluunbat; Dashnyam, Bumbein; Ahhmed, Abdulatef M; Kawahara, Satoshi; Muguruma, Michio

    2011-08-01

    The aims of this study were to investigate the diversity of lactic acid bacteria (LAB) isolated from traditional Mongolian dairy products, and to estimate the probiotic potential of the isolated strains. We collected 66 samples of the traditional Mongolian dairy products tarag (n = 45), airag (n = 7), aaruul (n = 8), byasulag (n = 1) and eezgii (n = 5), from which 543 LAB strains were isolated and identified based on 16S ribosomal DNA sequence. The predominant species of those products were Lactobacillus (L.) delbrueckii ssp. bulgaricus, L. helveticus, L. fermentum, L. delbrueckii ssp. lactis and Lactococcus lactis ssp. lactis. However, we could not detect any LAB strains from eezgii. All LAB isolates were screened for tolerance to low pH and to bile acid, gas production from glucose, and adherence to Caco-2 cells. In vitro, we found 10 strains possess probiotic properties, and almost identified them as L. plantarum or L. paracasei subspecies, based on 16S ribosomal DNA and carbohydrate fermentation pattern. These strains were differentiated from each other individually by randomly amplified polymorphic DNA analysis. Additionally, it was notable that 6/10 strains were isolated from camel milk tarag from the Dornogovi province. 2011 The Authors. Animal Science Journal © 2011 Japanese Society of Animal Science.

  13. Prescription omega-3 fatty acid products containing highly purified eicosapentaenoic acid (EPA).

    PubMed

    Brinton, Eliot A; Mason, R Preston

    2017-01-31

    The omega-3 fatty acid eicosapentaenoic acid (EPA) has multiple actions potentially conferring cardiovascular benefit, including lowering serum triglyceride (TG) and non-high-density lipoprotein cholesterol (non-HDL-C) levels and potentially reducing key steps in atherogenesis. Dietary supplements are a common source of omega-3 fatty acids in the US, but virtually all contain docosahexaenoic acid (DHA) in addition to EPA, and lipid effects differ between DHA and EPA. Contrary to popular belief, no over-the-counter omega-3 products are available in the US, only prescription products and dietary supplements. Among the US prescription omega-3 products, only one contains EPA exclusively (Vascepa); another closely related prescription omega-3 product also contains highly purified EPA, but is approved only in Japan and is provided in different capsule sizes. These high-purity EPA products do not raise low-density lipoprotein cholesterol (LDL-C) levels, even in patients with TG levels >500 mg/dL, in contrast to the increase in LDL-C levels with prescription omega-3 products that also contain DHA. The Japanese prescription EPA product was shown to significantly reduce major coronary events in hypercholesterolemic patients when added to statin therapy in the Japan EPA Lipid Intervention Study (JELIS). The effects of Vascepa on cardiovascular outcomes are being investigated in statin-treated patients with high TG levels in the Reduction of Cardiovascular Events With EPA-Intervention Trial (REDUCE-IT).

  14. Acetic acid production from food wastes using yeast and acetic acid bacteria micro-aerobic fermentation.

    PubMed

    Li, Yang; He, Dongwei; Niu, Dongjie; Zhao, Youcai

    2015-05-01

    In this study, yeast and acetic acid bacteria strains were adopted to enhance the ethanol-type fermentation resulting to a volatile fatty acids yield of 30.22 g/L, and improve acetic acid production to 25.88 g/L, with food wastes as substrate. In contrast, only 12.81 g/L acetic acid can be obtained in the absence of strains. The parameters such as pH, oxidation reduction potential and volatile fatty acids were tested and the microbial diversity of different strains and activity of hydrolytic ferment were investigated to reveal the mechanism. The optimum pH and oxidation reduction potential for the acetic acid production were determined to be at 3.0-3.5 and -500 mV, respectively. Yeast can convert organic matters into ethanol, which is used by acetic acid bacteria to convert the organic wastes into acetic acid. The acetic acid thus obtained from food wastes micro-aerobic fermentation liquid could be extracted by distillation to get high-pure acetic acid.

  15. Production of caffeoylmalic acid from glucose in engineered Escherichia coli.

    PubMed

    Li, Tianzhen; Zhou, Wei; Bi, Huiping; Zhuang, Yibin; Zhang, Tongcun; Liu, Tao

    2018-07-01

    To achieve biosynthesis of caffeoylmalic acid from glucose in engineered Escherichia coli. We constructed the biosynthetic pathway of caffeoylmalic acid in E. coli by co-expression of heterologous genes RgTAL, HpaBC, At4CL2 and HCT2. To enhance the production of caffeoylmalic acid, we optimized the tyrosine metabolic pathway of E. coli to increase the supply of the substrate caffeic acid. Consequently, an E. coli-E. coli co-culture system was used for the efficient production of caffeoylmalic acid. The final titer of caffeoylmalic acid reached 570.1 mg/L. Microbial production of caffeoylmalic acid using glucose has application potential. In addition, microbial co-culture is an efficient tool for producing caffeic acid esters.

  16. Potential for mcl-PHA production from nonanoic and azelaic acids.

    PubMed

    Gillis, James; Ko, Kenton; Ramsay, Juliana A; Ramsay, Bruce A

    2018-01-01

    Greater than 65% of canola and high-oleic soy oil fatty acids is oleic acid, which is readily converted to nonanoic (NA) and azelaic (AzA) acids by ozonolysis. NA is an excellent substrate for medium-chain-length polyhydroxyalkanoate (mcl-PHA) production but AzA has few uses. Pseudomonas citronellolis DSM 50332 and Pseudomonas fluorescens ATCC 17400, both able to produce mcl-PHA from fatty acids and to grow on AzA as the sole source of carbon and energy, were assessed for the accumulation of mcl-PHA from AzA and NA. In N-limited shake flasks using NA, P. citronellolis produced 32% of its dry biomass as mcl-PHA containing 78% 3-hydroxynonanoate with 22% 3-hydroxyheptanoate. Pseudomonas fluorescens produced only 2% PHA. N-limited P. citronellolis on AzA produced 20% dry weight PHA containing 75% 3-hydroxydecanoate and 25% 3-hydroxyoctanoate, indicative of de novo synthesis. Although selective pressure, including β-oxidation inhibition, under well-controlled (chemostat) conditions was applied to P. citronellolis, no side-chain carboxyl groups were detected. It was concluded that one or more of FabG and PhaJ or the PHA synthase cannot catalyze reactions involving ω-carboxy substrates. However, a process based on oleic acid could be established if Pseudomonas putida was engineered to grow on AzA.

  17. Potential bronchoconstrictor stimuli in acid fog.

    PubMed Central

    Balmes, J R; Fine, J M; Gordon, T; Sheppard, D

    1989-01-01

    Acid fog is complex and contains multiple stimuli that may be capable of inducing bronchoconstriction. These stimuli include sulfuric and niric acids, the principal inorganic acids present; sulfites, formed in the atmosphere as a reaction product of sulfur dioxide and water droplets; fog water itself, a hypoosmolar aerosol; the organic acid hydroxymethanesulfonate, the bisulfite adduct of formaldehyde; and gaseous pollutants, e.g., sulfur dioxide, oxides of nitrogen, ozone. Given this complexity, evaluation of the respiratory health effects of naturally occurring acid fog requires assessment of the bronchoconstrictor potency of each component stimulus and possible interactions among these stimuli. We summarize the results of three studies that involve characterization of the bronchoconstrictor potency of acid fog stimuli and/or their interaction in subjects with asthma. The results of the first study indicate that titratable acidity appears to be a more important stimulus to bronchoconstriction than is pH. The results of the second study demonstrate that sulfite species are capable of inducing bronchoconstriction, especially when inhaled at acid pH. The results of the third study suggest that acidity can potentiate hypoosmolar fog-induced bronchoconstriction. PMID:2539989

  18. Amino acids production focusing on fermentation technologies - A review.

    PubMed

    D'Este, Martina; Alvarado-Morales, Merlin; Angelidaki, Irini

    Amino acids are attractive and promising biochemicals with market capacity requirements constantly increasing. Their applicability ranges from animal feed additives, flavour enhancers and ingredients in cosmetic to specialty nutrients in pharmaceutical and medical fields. This review gives an overview of the processes applied for amino acids production and points out the main advantages and disadvantages of each. Due to the advances made in the genetic engineering techniques, the biotechnological processes, and in particular the fermentation with the aid of strains such as Corynebacterium glutamicum or Escherichia coli, play a significant role in the industrial production of amino acids. Despite the numerous advantages of the fermentative amino acids production, the process still needs significant improvements leading to increased productivity and reduction of the production costs. Although the production processes of amino acids have been extensively investigated in previous studies, a comprehensive overview of the developments in bioprocess technology has not been reported yet. This review states the importance of the fermentation process for industrial amino acids production, underlining the strengths and the weaknesses of the process. Moreover, the potential of innovative approaches utilizing macro and microalgae or bacteria are presented. Copyright © 2017 Elsevier Inc. All rights reserved.

  19. Adipic acid production catalyzed by a combination of a solid acid and an iodide salt from biomass-derived tetrahydrofuran-2,5-dicarboxylic acid

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

    Gilkey, Matthew J.; Balakumar, Rachana; Vlachos, Dionisios G.

    We recently reported biomass-derived tetrahydrofuran-2,5-dicarboxylic acid (THFDCA) as a potential renewable feedstock for adipic acid (AA) production by combining HI and molecular H 2 in organic acid solvents.

  20. Adipic acid production catalyzed by a combination of a solid acid and an iodide salt from biomass-derived tetrahydrofuran-2,5-dicarboxylic acid

    DOE PAGES

    Gilkey, Matthew J.; Balakumar, Rachana; Vlachos, Dionisios G.; ...

    2018-01-01

    We recently reported biomass-derived tetrahydrofuran-2,5-dicarboxylic acid (THFDCA) as a potential renewable feedstock for adipic acid (AA) production by combining HI and molecular H 2 in organic acid solvents.

  1. Food acid content and erosive potential of sugar-free confections.

    PubMed

    Shen, P; Walker, G D; Yuan, Y; Reynolds, C; Stacey, M A; Reynolds, E C

    2017-06-01

    Dental erosion is an increasingly prevalent problem associated with frequent consumption of acidic foods and beverages. The aim of this study was to measure the food acid content and the erosive potential of a variety of sugar-free confections. Thirty sugar-free confections were selected and extracts analysed to determine pH, titratable acidity, chemical composition and apparent degree of saturation with respect to apatite. The effect of the sugar-free confections in artificial saliva on human enamel was determined in an in vitro dental erosion assay using change in surface microhardness. The change in surface microhardness was used to categorize the confections as high, moderate or low erosive potential. Seventeen of the 30 sugar-free confections were found to contain high concentrations of food acids, exhibit low pH and high titratable acidity and have high erosive potential. Significant correlations were found between the dental erosive potential (change in enamel surface microhardness) and pH and titratable acidity of the confections. Ten of these high erosive potential confections displayed dental messages on the packaging suggesting they were safe for teeth. Many sugar-free confections, even some with 'Toothfriendly' messages on the product label, contain high contents of food acids and have erosive potential. © 2017 Australian Dental Association.

  2. Enhanced succinic acid production from corncob hydrolysate by microbial electrolysis cells.

    PubMed

    Zhao, Yan; Cao, Weijia; Wang, Zhen; Zhang, Bowen; Chen, Kequan; Ouyang, Pingkai

    2016-02-01

    In this study, Actinobacillus succinogenes NJ113 microbial electrolysis cells (MECs) were used to enhance the reducing power responsible for succinic acid production from corncob hydrolysate. During corncob hydrolysate fermentation, electric MECs resulted in a 1.31-fold increase in succinic acid production and a 1.33-fold increase in the reducing power compared with those in non-electric MECs. When the hydrolysate was detoxified by combining Ca(OH)2, NaOH, and activated carbon, succinic acid production increased from 3.47 to 6.95 g/l. Using a constant potential of -1.8 V further increased succinic acid production to 7.18 g/l. A total of 18.09 g/l of succinic acid and a yield of 0.60 g/g total sugar were obtained after a 60-h fermentation when NaOH was used as a pH regulator. The improved succinic acid yield from corncob hydrolysate fermentation using A. succinogenes NJ113 in electric MECs demonstrates the great potential of using biomass as a feedstock to cost-effectively produce succinate. Copyright © 2015 Elsevier Ltd. All rights reserved.

  3. Process for chemical reaction of amino acids and amides yielding selective conversion products

    DOEpatents

    Holladay, Jonathan E [Kennewick, WA

    2006-05-23

    The invention relates to processes for converting amino acids and amides to desirable conversion products including pyrrolidines, pyrrolidinones, and other N-substituted products. L-glutamic acid and L-pyroglutamic acid provide general reaction pathways to numerous and valuable selective conversion products with varied potential industrial uses.

  4. Recent advances in lactic acid production by microbial fermentation processes.

    PubMed

    Abdel-Rahman, Mohamed Ali; Tashiro, Yukihiro; Sonomoto, Kenji

    2013-11-01

    Fermentative production of optically pure lactic acid has roused interest among researchers in recent years due to its high potential for applications in a wide range of fields. More specifically, the sharp increase in manufacturing of biodegradable polylactic acid (PLA) materials, green alternatives to petroleum-derived plastics, has significantly increased the global interest in lactic acid production. However, higher production costs have hindered the large-scale application of PLA because of the high price of lactic acid. Therefore, reduction of lactic acid production cost through utilization of inexpensive substrates and improvement of lactic acid production and productivity has become an important goal. Various methods have been employed for enhanced lactic acid production, including several bioprocess techniques facilitated by wild-type and/or engineered microbes. In this review, we will discuss lactic acid producers with relation to their fermentation characteristics and metabolism. Inexpensive fermentative substrates, such as dairy products, food and agro-industrial wastes, glycerol, and algal biomass alternatives to costly pure sugars and food crops are introduced. The operational modes and fermentation methods that have been recently reported to improve lactic acid production in terms of concentrations, yields, and productivities are summarized and compared. High cell density fermentation through immobilization and cell-recycling techniques are also addressed. Finally, advances in recovery processes and concluding remarks on the future outlook of lactic acid production are presented. Copyright © 2013 Elsevier Inc. All rights reserved.

  5. Analysis of Organic Acids, Deacetyl Asperulosidic Acid and Polyphenolic Compounds as a Potential Tool for Characterization of Noni (Morinda citrifolia) Products.

    PubMed

    Bittová, Miroslava; Hladůkova, Dita; Roblová, Vendula; Krácmar, Stanislav; Kubán, Petr; Kubán, Vlastimil

    2015-11-01

    Organic acids, deacetyl asperulosidic acid (DAA) and polyphenolic compounds in various noni (Morinda citrifolia L.) products (4 juices, 4 dry fruit powders and 2 capsules with dry fruit powder) were analyzed. Reversed-phase high-performance liquid chromatography (RP-HPLC) coupled with a variable wavelength detector (VWD) and electrospray ionization time-of-flight mass spectrometer (ESI-TOF MS) was applied for simultaneous analysis of organic acids (malic, lactic, citric and succinic acid) and DAA. An RP-HPLC method with diode-array detector (DAD) was developed for the analysis of polyphenolic compound content (rutin, catechin, quercitrin, kaempferol, gallic acid, caffeic acid and p-coumaric acid). The developed methods can contribute to better characterization of available noni products that is required from the consumers. In our study, we discovered significant dissimilarities in the content of DAA, citric acid and several phenolic compounds in some samples.

  6. Physiological functions and pathogenic potential of uric acid: A review.

    PubMed

    El Ridi, Rashika; Tallima, Hatem

    2017-09-01

    Uric acid is synthesized mainly in the liver, intestines and the vascular endothelium as the end product of an exogenous pool of purines, and endogenously from damaged, dying and dead cells, whereby nucleic acids, adenine and guanine, are degraded into uric acid. Mentioning uric acid generates dread because it is the established etiological agent of the severe, acute and chronic inflammatory arthritis, gout and is implicated in the initiation and progress of the metabolic syndrome. Yet, uric acid is the predominant anti-oxidant molecule in plasma and is necessary and sufficient for induction of type 2 immune responses. These properties may explain its protective potential in neurological and infectious diseases, mainly schistosomiasis. The pivotal protective potential of uric acid against blood-borne pathogens and neurological and autoimmune diseases is yet to be established.

  7. Anti-inflammatory potential of ellagic acid, gallic acid and punicalagin A&B isolated from Punica granatum.

    PubMed

    BenSaad, Lamees A; Kim, Kah Hwi; Quah, Chin Chew; Kim, Wee Ric; Shahimi, Mustafa

    2017-01-14

    Punica granatum (pomegranate), an edible fruit originating in the Middle East, has been used as a traditional medicine for treatment of pain and inflammatory conditions such as peptic ulcer. The numerous risks associated with nonsteroidal anti-inflammatory drugs (NSAIDs) for treatment of pain and inflammation give rise to using medicinal herbs as alternative therapies. This study aimed to evaluate the anti-inflammatory effect of isolated compounds from the ethyl acetate (EtOAc) fraction of P. granatum by determination of their inhibitory effects on lipopolysaccharide (LPS), stimulated nitric oxide (NO), prostaglandin E2 (PGE-2), interleukin-6 (IL-6) and cyclooxxgenase-2 (COX-2) release from RAW264.7 cells. The compounds ellagic acid, gallic acid and punicalagin A&B were isolated from EtOAc by high performance liquid chromatography (HPLC) and further identified by mass spectrometry (MS). The inhibitory effect of ellagic acid, gallic acid and punicalagin A&B were evaluated on the production of LPS-induced NO by Griess reagent, PGE-2 and IL-6 by immunoassay kit and prostaglandin E2 competitive ELISA kit, and COX-2 by Western blotting. Ellagic acid, gallic acid and punicalagin A&B potentially inhibited LPS-induced NO, PGE-2 and IL-6 production. The results indicate that ellagic acid, gallic acid and punicalagin may be the compounds responsible for the anti-inflammatory potential of P. granatum.

  8. Malic acid production from thin stillage by Aspergillus species.

    PubMed

    West, Thomas P

    2011-12-01

    The ability of Aspergillus strains to utilize thin stillage to produce malic acid was compared. The highest malic acid was produced by Aspergillus niger ATCC 9142 at 17 g l(-1). Biomass production from thin stillage was similar with all strains but ATCC 10577 was the highest at 19 g l(-1). The highest malic acid yield (0.8 g g(-1)) was with A. niger ATCC 9142 and ATCC 10577 on the stillage. Thus, thin stillage has the potential to act as a substrate for the commercial production of food-grade malic acid by the A. niger strains. © Springer Science+Business Media B.V. 2011

  9. Antimicrobial potential of bioconverted products of omega-3 fatty acids by Pseudomonas aeruginosa PR3

    USDA-ARS?s Scientific Manuscript database

    Bioconverted omega-3 fatty acids, eicosapentaenoic acid (bEPA) and docosahexanoic acid (bDHA), obtained from the microbial conversion of non-bioconverted eicosapentaenoic and docosahexaenoic acids by Pseudomonas aeruginosa PR3 were evaluated for their antimicrobial potential. bEPA and bDHA at 5 µl/...

  10. Production of lactic acid using a new homofermentative Enterococcus faecalis isolate

    PubMed Central

    Subramanian, Mohan Raj; Talluri, Suvarna; Christopher, Lew P

    2015-01-01

    Lactic acid is an intermediate-volume specialty chemical for a wide range of food and industrial applications such as pharmaceuticals, cosmetics and chemical syntheses. Although lactic acid production has been well documented, improved production parameters that lead to reduced production costs are always of interest in industrial developments. In this study, we describe the production of lactic acid at high concentration, yield and volumetric productivity utilizing a novel homofermentative, facultative anaerobe Enterococcus faecalis CBRD01. The highest concentration of 182 g lactic acid l−1 was achieved after 38 h of fed-batch fermentation on glucose. The bacterial isolate utilized only 2–13% of carbon for its growth and energy metabolism, while 87–98% of carbon was converted to lactic acid at an overall volumetric productivity of 5 g l−1 h−1. At 13 h of fermentation, the volumetric productivity of lactate production reached 10.3 g l−1 h−1, which is the highest ever reported for microbial production of lactic acid. The lactic acid produced was of high purity as formation of other metabolites was less than 0.1%. The present investigation demonstrates a new opportunity for enhanced production of lactic acid with potential for reduced purification costs. PMID:24894833

  11. Potential Antagonist of Folic Acid Metabolism as Malarial Drugs,

    DTIC Science & Technology

    1982-09-01

    which sen.irited from the hydrocloric acid was filtered and then washed with water (25 ml). The reaction gave 2.3 g of the product which melted be...neutralized with cold dilute hydrocloric acid and evaporated to dryness. The residue was then extracted with methylene chloride filtered, and again...FhGh6/15hEE 1281 12.5 ~I1.50 IIA 132ii MJCRc)tll I’RE SOLU i UN ltIS CHiARI AD FINAL REPORT POTENTIAL ANTAGONIST OF FOLIC ACID METABOLISM AS MALARIAL

  12. Uric acid disrupts hypochlorous acid production and the bactericidal activity of HL-60 cells.

    PubMed

    Carvalho, Larissa A C; Lopes, João P P B; Kaihami, Gilberto H; Silva, Railmara P; Bruni-Cardoso, Alexandre; Baldini, Regina L; Meotti, Flavia C

    2018-06-01

    Uric acid is the end product of purine metabolism in humans and is an alternative physiological substrate for myeloperoxidase. Oxidation of uric acid by this enzyme generates uric acid free radical and urate hydroperoxide, a strong oxidant and potentially bactericide agent. In this study, we investigated whether the oxidation of uric acid and production of urate hydroperoxide would affect the killing activity of HL-60 cells differentiated into neutrophil-like cells (dHL-60) against a highly virulent strain (PA14) of the opportunistic pathogen Pseudomonas aeruginosa. While bacterial cell counts decrease due to dHL-60 killing, incubation with uric acid inhibits this activity, also decreasing the release of the inflammatory cytokines interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF- α). In a myeloperoxidase/Cl - /H 2 O 2 cell-free system, uric acid inhibited the production of HOCl and bacterial killing. Fluorescence microscopy showed that uric acid also decreased the levels of HOCl produced by dHL-60 cells, while significantly increased superoxide production. Uric acid did not alter the overall oxidative status of dHL-60 cells as measured by the ratio of reduced (GSH) and oxidized (GSSG) glutathione. Our data show that uric acid impairs the killing activity of dHL-60 cells likely by competing with chloride by myeloperoxidase catalysis, decreasing HOCl production. Despite diminishing HOCl, uric acid probably stimulates the formation of other oxidants, maintaining the overall oxidative status of the cells. Altogether, our results demonstrated that HOCl is, indeed, the main relevant oxidant against bacteria and deviation of myeloperoxidase activity to produce other oxidants hampers dHL-60 killing activity. Copyright © 2018 The Authors. Published by Elsevier B.V. All rights reserved.

  13. Engineering the production of conjugated fatty acids in Arabidopsis thaliana leaves

    USDA-ARS?s Scientific Manuscript database

    The seeds of many non-domesticated plant species synthesize oils containing high amounts of a single unusual fatty acid, many of which have potential usage in industry. Despite the identification of enzymes for unusual oxidized fatty acid synthesis, the production of these fatty acids in engineered ...

  14. Overexpression of a C4-dicarboxylate transporter is the key for rerouting citric acid to C4-dicarboxylic acid production in Aspergillus carbonarius.

    PubMed

    Yang, Lei; Christakou, Eleni; Vang, Jesper; Lübeck, Mette; Lübeck, Peter Stephensen

    2017-03-14

    C 4 -dicarboxylic acids, including malic acid, fumaric acid and succinic acid, are valuable organic acids that can be produced and secreted by a number of microorganisms. Previous studies on organic acid production by Aspergillus carbonarius, which is capable of producing high amounts of citric acid from varieties carbon sources, have revealed its potential as a fungal cell factory. Earlier attempts to reroute citric acid production into C 4 -dicarboxylic acids have been with limited success. In this study, a glucose oxidase deficient strain of A. carbonarius was used as the parental strain to overexpress a native C 4 -dicarboxylate transporter and the gene frd encoding fumarate reductase from Trypanosoma brucei individually and in combination. Impacts of the introduced genetic modifications on organic acid production were investigated in a defined medium and in a hydrolysate of wheat straw containing high concentrations of glucose and xylose. In the defined medium, overexpression of the C 4 -dicarboxylate transporter alone and in combination with the frd gene significantly increased the production of C 4 -dicarboxylic acids and reduced the accumulation of citric acid, whereas expression of the frd gene alone did not result in any significant change of organic acid production profile. In the wheat straw hydrolysate after 9 days of cultivation, similar results were obtained as in the defined medium. High amounts of malic acid and succinic acid were produced by the same strains. This study demonstrates that the key to change the citric acid production into production of C 4 -dicarboxylic acids in A. carbonarius is the C 4 -dicarboxylate transporter. Furthermore it shows that the C 4 -dicarboxylic acid production by A. carbonarius can be further increased via metabolic engineering and also shows the potential of A. carbonarius to utilize lignocellulosic biomass as substrates for C 4 -dicarboxylic acid production.

  15. Detoxification of acidic biorefinery waste liquor for production of high value amino acid.

    PubMed

    Christopher, Meera; Anusree, Murali; Mathew, Anil K; Nampoothiri, K Madhavan; Sukumaran, Rajeev Kumar; Pandey, Ashok

    2016-08-01

    The current study evaluates the detoxification of acid pretreatment liquor (APL) using adsorbent (ADS 400 & ADS 800) or ion-exchange (A-27MP & A-72MP) resins and its potential for amino acid production. The APL is generated as a by-product from the pretreatment of lignocellulosic biomass and is rich monomeric sugars as well as sugar degradation products (fermentation inhibitors) such as furfural and hydroxymethyl furfural (HMF). Of the four resins compared, ADS 800 removed approximately 85% and 60% of furfural and HMF, respectively. ADS 800 could be reused for up to six cycles after regeneration without losing its adsorption properties. The study was further extended by assessing the fermentability of detoxified APL for l-lysine production using wild and mutant strains of Corynebacterium glutamicum. The detoxified APL was superior to APL for l-lysine production. Copyright © 2016 Elsevier Ltd. All rights reserved.

  16. Formic acid catalyzed hydrolysis of SO3 in the gas phase: a barrierless mechanism for sulfuric acid production of potential atmospheric importance.

    PubMed

    Hazra, Montu K; Sinha, Amitabha

    2011-11-02

    Computational studies at the B3LYP/6-311++G(3df,3pd) and MP2/6-311++G(3df,3pd) levels are performed to explore the changes in reaction barrier height for the gas phase hydrolysis of SO(3) to form H(2)SO(4) in the presence of a single formic acid (FA) molecule. For comparison, we have also performed calculations for the reference reaction involving water assisted hydrolysis of SO(3) at the same level. Our results show that the FA assisted hydrolysis of SO(3) to form H(2)SO(4) is effectively a barrierless process. The barrier heights for the isomerization of the SO(3)···H(2)O···FA prereactive collision complex, which is the rate limiting step in the FA assisted hydrolysis, are found to be respectively 0.59 and 0.08 kcal/mol at the B3LYP/6-311++G(3df,3pd) and MP2/6-311++G(3df,3pd) levels. This is substantially lower than the ~7 kcal/mol barrier for the corresponding step in the hydrolysis of SO(3) by two water molecules--which is currently the accepted mechanism for atmospheric sulfuric acid production. Simple kinetic analysis of the relative rates suggests that the reduction in barrier height facilitated by FA, combined with the greater stability of the prereactive SO(3)···H(2)O···FA collision complex compared to SO(3)···H(2)O···H(2)O and the rather plentiful atmospheric abundance of FA, makes the formic acid mediated hydrolysis reaction a potentially important pathway for atmospheric sulfuric acid production.

  17. Triacetic acid lactone production from Saccharomyces cerevisiae

    USDA-ARS?s Scientific Manuscript database

    Triacetic acid lactone (TAL) is a potential platform chemical produced from acetyl-CoA and malonyl-CoA by the Gerbera hybrida 2-pyrone synthase (2PS) gene. Studies are ongoing to optimize production, purification, and chemical modification of TAL, which can be used to create the commercial chemicals...

  18. Production of carboxylic acid and salt co-products

    DOEpatents

    Hanchar, Robert J.; Kleff, Susanne; Guettler, Michael V.

    2014-09-09

    This invention provide processes for producing carboxylic acid product, along with useful salts. The carboxylic acid product that is produced according to this invention is preferably a C.sub.2-C.sub.12 carboxylic acid. Among the salts produced in the process of the invention are ammonium salts.

  19. L-Lactic acid production from glycerol coupled with acetic acid metabolism by Enterococcus faecalis without carbon loss.

    PubMed

    Murakami, Nao; Oba, Mana; Iwamoto, Mariko; Tashiro, Yukihiro; Noguchi, Takuya; Bonkohara, Kaori; Abdel-Rahman, Mohamed Ali; Zendo, Takeshi; Shimoda, Mitsuya; Sakai, Kenji; Sonomoto, Kenji

    2016-01-01

    Glycerol is a by-product in the biodiesel production process and considered as one of the prospective carbon sources for microbial fermentation including lactic acid fermentation, which has received considerable interest due to its potential application. Enterococcus faecalis isolated in our laboratory produced optically pure L-lactic acid from glycerol in the presence of acetic acid. Gas chromatography-mass spectrometry analysis using [1, 2-(13)C2] acetic acid proved that the E. faecalis strain QU 11 was capable of converting acetic acid to ethanol during lactic acid fermentation of glycerol. This indicated that strain QU 11 restored the redox balance by oxidizing excess NADH though acetic acid metabolism, during ethanol production, which resulted in lactic acid production from glycerol. The effects of pH control and substrate concentration on lactic acid fermentation were also investigated. Glycerol and acetic acid concentrations of 30 g/L and 10 g/L, respectively, were expected to be appropriate for lactic acid fermentation of glycerol by strain QU 11 at a pH of 6.5. Furthermore, fed-batch fermentation with 30 g/L glycerol and 10 g/L acetic acid wholly exhibited the best performance including lactic acid production (55.3 g/L), lactic acid yield (0.991 mol-lactic acid/mol-glycerol), total yield [1.08 mol-(lactic acid and ethanol)]/mol-(glycerol and acetic acid)], and total carbon yield [1.06 C-mol-(lactic acid and ethanol)/C-mol-(glycerol and acetic acid)] of lactic acid and ethanol. In summary, the strain QU 11 successfully produced lactic acid from glycerol with acetic acid metabolism, and an efficient fermentation system was established without carbon loss. Copyright © 2015 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  20. The microbial communities and potential greenhouse gas production in boreal acid sulphate, non-acid sulphate, and reedy sulphidic soils.

    PubMed

    Šimek, Miloslav; Virtanen, Seija; Simojoki, Asko; Chroňáková, Alica; Elhottová, Dana; Krištůfek, Václav; Yli-Halla, Markku

    2014-01-01

    Acid sulphate (AS) soils along the Baltic coasts contain significant amounts of organic carbon and nitrogen in their subsoils. The abundance, composition, and activity of microbial communities throughout the AS soil profile were analysed. The data from a drained AS soil were compared with those from a drained non-AS soil and a pristine wetland soil from the same region. Moreover, the potential production of methane, carbon dioxide, and nitrous oxide from the soils was determined under laboratory conditions. Direct microscopic counting, glucose-induced respiration (GIR), whole cell hybridisation, and extended phospholipid fatty acid (PLFA) analysis confirmed the presence of abundant microbial communities in the topsoil and also in the deepest Cg2 horizon of the AS soil. The patterns of microbial counts, biomass and activity in the profile of the AS soil and partly also in the non-AS soil therefore differed from the general tendency of gradual decreases in soil profiles. High respiration in the deepest Cg2 horizon of the AS soil (5.66 μg Cg(-1)h(-1), as compared to 2.71 μg Cg(-1)h(-1) in a top Ap horizon) is unusual but reasonable given the large amount of organic carbon in this horizon. Nitrous oxide production peaked in the BCgc horizon of the AS and in the BC horizon of the non-AS soil, but the peak value was ten-fold higher in the AS soil than in the non-AS soil (82.3 vs. 8.6 ng Ng(-1)d(-1)). The data suggest that boreal AS soils on the Baltic coast contain high microbial abundance and activity. This, together with the abundant carbon and total and mineral nitrogen in the deep layers of AS soils, may result in substantial gas production. Consequently, high GHG emissions could occur, for example, when the generally high water table is lowered because of arable farming. © 2013.

  1. World market and biotechnological production of itaconic acid.

    PubMed

    Cunha da Cruz, Juliana; Machado de Castro, Aline; Camporese Sérvulo, Eliana Flávia

    2018-03-01

    The itaconic acid (IA) world market is expected to exceed 216 million of dollars by 2020 as a result of an increasing demand for bio-based chemicals. The potential of this organic acid produced by fermentation mainly with filamentous fungi relies on the vast industrial applications of polymers derived from it. The applications may be as a superabsorbent polymer for personal care or agriculture, unsaturated polyester resin for the transportation industry, poly(methyl methacrylate) for electronic devices, among many others. However, the existence of other substitutes and the high production cost limit the current IA market. IA manufacturing is done mainly in China and other Asia-Pacific countries. Higher economic feasibility and production worldwide may be achieved with the use of low-cost feedstock of local origin and with the development of applications targeted to specific local markets. Moreover, research on the biological pathway for IA synthesis and the effect of medium composition are important for amplifying the knowledge about the production of that biochemical with great market potential.

  2. Cereal-based biorefinery development: utilisation of wheat milling by-products for the production of succinic acid.

    PubMed

    Dorado, M Pilar; Lin, Sze Ki Carol; Koutinas, Apostolis; Du, Chenyu; Wang, Ruohang; Webb, Colin

    2009-08-10

    A novel wheat-based bioprocess for the production of a nutrient-complete feedstock for the fermentative succinic acid production by Actinobacillus succinogenes has been developed. Wheat was fractionated into bran, middlings and flour. The bran fraction, which would normally be a waste product of the wheat milling industry, was used as the sole medium in two solid-state fermentations (SSF) of Aspergillus awamori and Aspergillus oryzae that produce enzyme complexes rich in amylolytic and proteolytic enzymes, respectively. The resulting fermentation solids were then used as crude enzyme sources, by adding directly to an aqueous suspension of milled bran and middlings fractions (wheat flour milling by-products) to generate a hydrolysate containing over 95g/L glucose, 25g/L maltose and 300mg/L free amino nitrogen (FAN). This hydrolysate was then used as the sole medium for A. succinogenes fermentations, which led to the production of 50.6g/L succinic acid. Supplementation of the medium with yeast extract did not significantly improve succinic acid production though increasing the inoculum concentration to 20% did result in the production of 62.1g/L succinic acid. Results indicated that A. succinogenes cells were able to utilise glucose and maltose in the wheat hydrolysate for cell growth and succinic acid production. The proposed process could be potentially integrated into a wheat-milling process to upgrade the wheat flour milling by-products (WFMB) into succinic acid, one of the future platform chemicals of a sustainable chemical industry.

  3. Enzymatic Production of Ascorbic Acid-2-phosphate by Recombinant Acid Phosphatase.

    PubMed

    Zheng, Kai; Song, Wei; Sun, Anran; Chen, Xiulai; Liu, Jia; Luo, Qiuling; Wu, Jing

    2017-05-24

    In this study, an environmentally friendly and efficient enzymatic method for the synthesis of l-ascorbic acid-2-phosphate (AsA-2P) from l-ascorbic acid (AsA) was developed. The Pseudomonas aeruginosa acid phosphatase (PaAPase) was expressed in Escherichia coli BL21. The optimal temperature, optimal pH, K m , k cat , and catalytic efficiency of recombinant PaAPase were 50 °C, 5.0, 93 mM, 4.2 s -1 , and 2.7 mM -1 min -1 , respectively. The maximal dry cell weight and PaAPase phosphorylating activity reached 8.5 g/L and 1127.7 U/L, respectively. The highest AsA-2P concentration (50.0 g/L) and the maximal conversion (39.2%) were obtained by incubating 75 g/L intact cells with 88 g/L AsA and 160 g/L sodium pyrophosphate under optimal conditions (0.1 mM Ca 2+ , pH 4.0, 30 °C) for 10 h; the average AsA-2P production rate was 5.0 g/L/h, and the AsA-2P production system was successfully scaled up to a 7.5 L fermenter. Therefore, the enzymatic process showed great potential for production of AsA-2P in industry.

  4. Organic acid pretreatment of oil palm trunk: effect on enzymatic saccharification and ethanol production.

    PubMed

    Rattanaporn, Kittipong; Tantayotai, Prapakorn; Phusantisampan, Theerawut; Pornwongthong, Peerapong; Sriariyanun, Malinee

    2018-04-01

    Effective lignocellulosic biomass saccharification is one of the crucial requirements of biofuel production via fermentation process. Organic acid pretreatments have been gained much interests as one of the high potential methods for promoting enzymatic saccharification of lignocellulosic materials due to their lower hazardous properties and lower production of inhibitory by-products of fermentation than typical chemical pretreatment methods. In this study, three organic acids, including acetic acid, oxalic acid, and citric acid, were examined for improvement of enzymatic saccharification and bioethanol production from oil palm trunk biomass. Based on response surface methodology, oxalic acid pretreated biomass released the maximum reducing sugar of 144 mg/g-pretreated biomass at the optimum condition, which was higher than untreated samples for 2.30 times. The released sugar yield of oil palm trunk also corresponded to the results of FT-IR analysis, which revealed the physical modification of cellulose and hemicellulose surface structures of pretreated biomass. Nevertheless, citric acid pretreatment is the most efficient pretreatment method to improve bioethanol fermentation of Saccharomyces cerevisiae TISTR 5606 at 1.94 times higher than untreated biomass. These results highlighted the selection of organic acid pretreatment as a potential method for biofuel production from oil palm trunk feedstocks.

  5. Folic Acid Production by Engineered Ashbya gossypii.

    PubMed

    Serrano-Amatriain, Cristina; Ledesma-Amaro, Rodrigo; López-Nicolás, Rubén; Ros, Gaspar; Jiménez, Alberto; Revuelta, José Luis

    2016-11-01

    Folic acid (vitamin B 9 ) is the common name of a number of chemically related compounds (folates), which play a central role as cofactors in one-carbon transfer reactions. Folates are involved in the biosynthesis and metabolism of nucleotides and amino acids, as well as supplying methyl groups to a broad range of substrates, such as hormones, DNA, proteins, and lipids, as part of the methyl cycle. Humans and animals cannot synthesize folic acid and, therefore, need them in the diet. Folic acid deficiency is an important and underestimated problem of micronutrient malnutrition affecting billions of people worldwide. Therefore, the addition of folic acid as food additive has become mandatory in many countries thus contributing to a growing demand of the vitamin. At present, folic acid is exclusively produced by chemical synthesis despite its associated environmental burdens. In this work, we have metabolically engineered the industrial fungus Ashbya gossypii in order to explore its potential as a natural producer of folic acid. Overexpression of FOL genes greatly enhanced the synthesis of folates and identified GTP cyclohydrolase I as the limiting step. Metabolic flux redirection from competing pathways also stimulated folic acid production. Finally, combinatorial engineering synergistically increased the production of different bioactive forms of the folic vitamin. Overall, strains were constructed which produce 146-fold (6595µg/L) more vitamin than the wild-type and by far represents the highest yield reported. Copyright © 2016 International Metabolic Engineering Society. Published by Elsevier Inc. All rights reserved.

  6. The Rcs-Regulated Colanic Acid Capsule Maintains Membrane Potential in Salmonella enterica serovar Typhimurium

    PubMed Central

    Pando, Jasmine M.; Karlinsey, Joyce E.; Lara, Jimmie C.; Libby, Stephen J.

    2017-01-01

    ABSTRACT The Rcs phosphorelay and Psp (phage shock protein) systems are envelope stress responses that are highly conserved in gammaproteobacteria. The Rcs regulon was found to be strongly induced during metal deprivation of Salmonella enterica serovar Typhimurium lacking the Psp response. Nineteen genes activated by the RcsA-RcsB response regulator make up an operon responsible for the production of colanic acid capsular polysaccharide, which promotes biofilm development. Despite more than half a century of research, the physiological function of colanic acid has remained elusive. Here we show that Rcs-dependent colanic acid production maintains the transmembrane electrical potential and proton motive force in cooperation with the Psp response. Production of negatively charged exopolysaccharide covalently bound to the outer membrane may enhance the surface potential by increasing the local proton concentration. This provides a unifying mechanism to account for diverse Rcs/colanic acid-related phenotypes, including susceptibility to membrane-damaging agents and biofilm formation. PMID:28588134

  7. Heterotrophy of filamentous oleaginous microalgae Tribonema minus for potential production of lipid and palmitoleic acid.

    PubMed

    Zhou, Wenjun; Wang, Hui; Chen, Lin; Cheng, Wentao; Liu, Tianzhong

    2017-09-01

    Heterotrophic fermentation and high valuable co-product producing are thought to be effective ways to improve the economic viability and feasibility of commercial production of microalgae biofuels. This work reported the heterotrophic cultivation of Tribonema minus for lipid and palmitoleic acid (a novel functional fatty acid) production. Firstly, the heterotrophic ability of T. minus was identified for the first time with significant promotion in biomass and lipid productivity, and glucose and urea were then selected as the optimal carbon and nitrogen sources. Moreover, nutrient concentrations and culture conditions were optimized. Highest biomass and lipid productivity of 30.8gL -1 and 730mgL -1 d -1 were obtained respectively by adding 80gL -1 glucose at once. In addition, 2gL -1 urea, 0.8gL -1 K 2 HPO 4 , 24mgL -1 ammonium ferric citrate, initial pH of 6, and temperature of 27°C were determined as the appropriate conditions for heterotrophic growth and lipid production. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. Yeast Acid Phosphatases and Phytases: Production, Characterization and Commercial Prospects

    NASA Astrophysics Data System (ADS)

    Kaur, Parvinder; Satyanarayana, T.

    The element phosphorus is critical to all life forms as it forms the basic component of nucleic acids and ATP and has a number of indispensable biochemical roles. Unlike C or N, the biogeochemical cycling of phosphorus is very slow, and thus making it the growth-limiting element in most soils and aquatic systems. Phosphohydrolases (e.g. acid phosphatases and phytases) are enzymes that break the C-O-P ester bonds and provide available inorganic phosphorus from various inassimilable organic forms of phosphorus like phytates. These enzymes are of significant value in effectively combating phosphorus pollution. Although phytases and acid phosphatases are produced by various plants, animals and micro organisms, microbial sources are more promising for the production on a commercial scale. Yeasts being the simplest eukaryotes are ideal candidates for phytase and phos-phatase research due to their mostly non-pathogenic and GRAS status. They have not, however, been utilized to their full potential. This chapter focuses attention on the present state of knowledge on the production, characterization and potential commercial prospects of yeast phytases and acid phosphatases.

  9. Effects of global change factors on fatty acids and mycosporine-like amino acid production in Chroothece richteriana (Rhodophyta).

    PubMed

    Gonzalez-Silvera, Daniel; Pérez, Sandra; Korbee, Nathalie; Figueroa, Félix L; Asencio, Antonia D; Aboal, Marina; López-Jiménez, José Ángel

    2017-10-01

    Under natural conditions, Chroothece richteriana synthesizes a fairly high proportion of fatty acids. However, nothing is known about how environmental changes affect their production, or about the production of protective compounds, when colonies develop under full sunshine with high levels of UV radiation. In this study, wild colonies of C. richteriana were subjected to increasing temperature, conductivity, ammonium concentrations and photosynthetically active radiation (PAR), and UV radiations to assess the potential changes in lipid composition and mycosporine-like amino acids (MAAs) concentration. The PERMANOVA analysis detected no differences for the whole fatty acid profile among treatments, but the percentages of α-linolenic acid and total polyunsaturated fatty acids increased at the lowest assayed temperature. The percentages of linoleic and α-linolenic acids increased with lowering temperature. γ-linolenic and arachidonic acids decreased with increasing conductivity, and a high arachidonic acid concentration was related with increased conductivity. The samples exposed to UVB radiation showed higher percentages of eicosapentaenoic acid and total monounsaturated fatty acids, at the expense of saturated fatty acids. MAAs accumulation increased but not significantly at the lowest conductivity, and also with the highest PAR and UVR exposure, while ammonium and temperature had no effect. The observed changes are probably related with adaptations of both membrane fluidity to low temperature, and metabolism to protect cells against UV radiation damage. The results suggest the potential to change lipid composition and MAAs concentration in response to environmental stressful conditions due to climate change, and highlight the interest of the species in future research about the biotechnological production of both compound types. © 2017 Phycological Society of America.

  10. Itaconic acid production in microorganisms.

    PubMed

    Zhao, Meilin; Lu, Xinyao; Zong, Hong; Li, Jinyang; Zhuge, Bin

    2018-03-01

    Itaconic acid, 2-methylidenebutanedioic acid, is a precursor of polymers, chemicals, and fuels. Many fungi can synthesize itaconic acid; Aspergillus terreus and Ustilago maydis produce up to 85 and 53 g l -1 , respectively. Other organisms, including Aspergillus niger and yeasts, have been engineered to produce itaconic acid. However, the titer of itaconic acid is low compared with the analogous major fermentation product, citric acid, for which the yield is > 200 g l -1 . Here, we review two types of pathway for itaconic acid biosynthesis as well as recent advances by metabolic engineering strategies and process optimization to enhance itaconic acid productivity in native producers and heterologous hosts. We also propose further improvements to overcome existing problems.

  11. Screening of marine bacterial producers of polyunsaturated fatty acids and optimisation of production.

    PubMed

    Abd El Razak, Ahmed; Ward, Alan C; Glassey, Jarka

    2014-02-01

    Water samples from three different environments including Mid Atlantic Ridge, Red Sea and Mediterranean Sea were screened in order to isolate new polyunsaturated fatty acids (PUFAs) bacterial producers especially eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). Two hundred and fifty-one isolates were screened for PUFA production and among them the highest number of producers was isolated from the Mid-Atlantic Ridge followed by the Red Sea while no producers were found in the Mediterranean Sea samples. The screening strategy included a simple colourimetric method followed by a confirmation via GC/MS. Among the tested producers, an isolate named 66 was found to be a potentially high PUFA producer producing relatively high levels of EPA in particular. A Plackett-Burman statistical design of experiments was applied to screen a wide number of media components identifying glycerol and whey as components of a production medium. The potential low-cost production medium was optimised by applying a response surface methodology to obtain the highest productivity converting industrial by-products into value-added products. The maximum achieved productivity of EPA was 20 mg/g, 45 mg/l, representing 11% of the total fatty acids, which is approximately five times more than the amount produced prior to optimisation. The production medium composition was 10.79 g/l whey and 6.87 g/l glycerol. To our knowledge, this is the first investigation of potential bacteria PUFA producers from Mediterranean and Red Seas providing an evaluation of a colourimetric screening method as means of rapid screening of a large number of isolates.

  12. Inhibition effects of perfluoroalkyl acids on progesterone production in mLTC-1.

    PubMed

    Zhao, Wei; Cui, Ruina; Wang, Jianshe; Dai, Jiayin

    2017-06-01

    Perfluoroalkyl substances (PFASs) are a class of fluorine substituted carboxylic acid, sulfonic acid and alcohol, structurally similar to their corresponding parent compounds. Previous study demonstrated the potential endocrine disruption and reproductive toxicity of perfluorooctane sulfonic acid and perfluorooctanoic acid, two dominant PFASs in animals and humans. We explored the relationship between eleven perfluoroalkyl acids (PFAAs) with different carbon chain length and their ability to inhibit progesterone production in mouse Leydig tumor cells (mLTC-1). We found an obvious dose-response relationship between progesterone inhibition rate and PFAA exposure concentration in mLTC-1. The relative inhibition rate of progesterone by PFAAs was linearly related to the carbon chain length and molar refractivity of PFAAs. Mitochondrial membrane potential (MMP) decreased after PFAA exposure at the half-maximal inhibitory effect concentration (IC 50 ) of progesterone production in mLTC-1, while the reactive oxygen species (ROS) content increased significantly. These results imply that the inhibition effect of PFAAs on progesterone production might be due, in part, to ROS damage and the decrease in MMP in mLTC-1. Copyright © 2016. Published by Elsevier B.V.

  13. [Fatty acids in confectionery products].

    PubMed

    Daniewski, M; Mielniczuk, E; Jacórzyński, B; Pawlicka, M; Balas, J; Filipek, A; Górnicka, M

    2000-01-01

    The content of fat and fatty acids in 144 different confectionery products purchased on the market in Warsaw region during 1997-1999 have been investigated. In examined confectionery products considerable variability of both fat and fatty acids content have been found. The content of fat varied from 6.6% (coconut cookies) up to 40% (chocolate wafers). Saturated fatty acids were present in both cis and trans form. Especially trans fatty acids reach (above 50%) were fats extracted from nut wafers, coconuts wafers.

  14. Effect of Pyruvate Decarboxylase Knockout on Product Distribution Using Pichia pastoris (Komagataella phaffii) Engineered for Lactic Acid Production.

    PubMed

    Melo, Nadiele T M; Mulder, Kelly C L; Nicola, André Moraes; Carvalho, Lucas S; Menino, Gisele S; Mulinari, Eduardo; Parachin, Nádia S

    2018-02-16

    Lactic acid is the monomer unit of the bioplastic poly-lactic acid (PLA). One candidate organism for lactic acid production is Pichia pastoris , a yeast widely used for heterologous protein production. Nevertheless, this yeast has a poor fermentative capability that can be modulated by controlling oxygen levels. In a previous study, lactate dehydrogenase (LDH) activity was introduced into P. pastoris, enabling this yeast to produce lactic acid. The present study aimed to increase the flow of pyruvate towards the production of lactic acid in P. pastoris . To this end, a strain designated GLp was constructed by inserting the bovine lactic acid dehydrogenase gene (LDHb) concomitantly with the interruption of the gene encoding pyruvate decarboxylase (PDC). Aerobic fermentation, followed by micro-aerophilic culture two-phase fermentations, showed that the GLp strain achieved a lactic acid yield of 0.65 g/g. The distribution of fermentation products demonstrated that the acetate titer was reduced by 20% in the GLp strain with a concomitant increase in arabitol production: arabitol increased from 0.025 g/g to 0.174 g/g when compared to the GS115 strain. Taken together, the results show a significant potential for P. pastoris in producing lactic acid. Moreover, for the first time, physiological data regarding co-product formation have indicated the redox balance limitations of this yeast.

  15. Production of itaconic acid from acetate by engineering acid-tolerant Escherichia coli W.

    PubMed

    Noh, Myung Hyun; Lim, Hyun Gyu; Woo, Sung Hwa; Song, Jinyi; Jung, Gyoo Yeol

    2018-03-01

    Utilization of abundant and cheap carbon sources can effectively reduce the production cost and enhance the economic feasibility. Acetate is a promising carbon source to achieve cost-effective microbial processes. In this study, we engineered an Escherichia coli strain to produce itaconic acid from acetate. As acetate is known to inhibit cell growth, we initially screened for a strain with a high tolerance to 10 g/L of acetate in the medium, and the W strain was selected as the host. Subsequently, the WC strain was obtained by overexpression of cad (encoding cis-aconitate decarboxylase) using a synthetic promoter and 5' UTR. However, the WC strain produced only 0.13 g/L itaconic acid because of low acetate uptake. To improve the production, the acetate assimilating pathway and glyoxylate shunt pathway were amplified by overexpression of pathway genes as well as its deregulation. The resulting strain, WCIAG4 produced 3.57 g/L itaconic acid (16.1% of theoretical maximum yield) after 88 hr of fermentation with rapid acetate assimilation. These efforts support that acetate can be a potential feedstock for biochemical production with engineered E. coli. © 2017 Wiley Periodicals, Inc.

  16. Ethanesulfonic acid-based esterification of industrial acidic crude palm oil for biodiesel production.

    PubMed

    Hayyan, Adeeb; Mjalli, Farouq S; Hashim, Mohd Ali; Hayyan, Maan; AlNashef, Inas M; Al-Zahrani, Saeed M; Al-Saadi, Mohammed A

    2011-10-01

    An industrial grade acidic crude palm oil (ACPO) pre-treatment process was carried out using ethanesulfonic acid (ESA) as a catalyst in the esterification reaction. ESA was used in different dosages to reduce free fatty acid (FFA) to a minimum level for the second stage of biodiesel production via alkaline transesterification reaction. Different process operating conditions were optimized such as ESA dosage (0.25-3.5% wt/wt), methanol to ACPO molar ratio (1:1-20:1), reaction temperature (40-70 °C), and reaction time (3-150 min). This study revealed the potential use of abundant quantities of ACPO from oil palm mills for biodiesel production. The lab scale results showed the effectiveness of the pre-treatment process using ESA catalyst. Three consecutive catalyst recycling runs were achieved without significant degradation in its performance. Second and third reuse runs needed more reaction time to achieve the target level of FFA content. Esterification and transesterification using ESA and KOH respectively is proposed for biodiesel industrial scale production. The produced biodiesel meets the international standards specifications for biodiesel fuel (EN 14214 and ASTM D6751). Copyright © 2011 Elsevier Ltd. All rights reserved.

  17. POTENTIAL ABATEMENT PRODUCTION AND MARKETING OF BYPRODUCT SULFURIC ACID IN THE U.S

    EPA Science Inventory

    The report gives results of an evaluation of the market potential for sulfur and sulfuric acid byproducts of combustion in power plant boilers. (Air quality regulations require control of SOx emissions from power plant boilers. Recovery of sulfur in useful form would avoid waste ...

  18. Catalytic amino acid production from biomass-derived intermediates

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

    Deng, Weiping; Wang, Yunzhu; Zhang, Sui

    Amino acids are the building blocks for protein biosynthesis and find use in myriad industrial applications including in food for humans, in animal feed, and as precursors for bio-based plastics, among others. However, the development of efficient chemical methods to convert abundant and renewable feedstocks into amino acids has been largely unsuccessful to date. To that end, here we report a heterogeneous catalyst that directly transforms lignocellulosic biomass-derived a-hydroxyl acids into a-amino acids, including alanine, leucine, valine, aspartic acid, and phenylalanine in high yields. The reaction follows a dehydrogenation-reductive amination pathway, with dehydrogenation as the rate-determining step. Ruthenium nanoparticles supportedmore » on carbon nanotubes (Ru/CNT) exhibit exceptional efficiency compared with catalysts based on other metals, due to the unique, reversible enhancement effect of NH 3 on Ru in dehydrogenation. Based on the catalytic system, a two-step chemical process was designed to convert glucose into alanine in 43% yield, comparable with the well-established microbial cultivation process, and therefore, the present strategy enables a route for the production of amino acids from renewable feedstocks. Moreover, a conceptual process design employing membrane distillation to facilitate product purification is proposed and validated. Overall, this study offers a rapid and potentially more efficient chemical method to produce amino acids from woody biomass components.« less

  19. Catalytic amino acid production from biomass-derived intermediates

    PubMed Central

    Deng, Weiping; Zhang, Sui; Gupta, Krishna M.; Hülsey, Max J.; Asakura, Hiroyuki; Liu, Lingmei; Han, Yu; Karp, Eric M.; Jiang, Jianwen; Tanaka, Tsunehiro; Wang, Ye

    2018-01-01

    Amino acids are the building blocks for protein biosynthesis and find use in myriad industrial applications including in food for humans, in animal feed, and as precursors for bio-based plastics, among others. However, the development of efficient chemical methods to convert abundant and renewable feedstocks into amino acids has been largely unsuccessful to date. To that end, here we report a heterogeneous catalyst that directly transforms lignocellulosic biomass-derived α-hydroxyl acids into α-amino acids, including alanine, leucine, valine, aspartic acid, and phenylalanine in high yields. The reaction follows a dehydrogenation-reductive amination pathway, with dehydrogenation as the rate-determining step. Ruthenium nanoparticles supported on carbon nanotubes (Ru/CNT) exhibit exceptional efficiency compared with catalysts based on other metals, due to the unique, reversible enhancement effect of NH3 on Ru in dehydrogenation. Based on the catalytic system, a two-step chemical process was designed to convert glucose into alanine in 43% yield, comparable with the well-established microbial cultivation process, and therefore, the present strategy enables a route for the production of amino acids from renewable feedstocks. Moreover, a conceptual process design employing membrane distillation to facilitate product purification is proposed and validated. Overall, this study offers a rapid and potentially more efficient chemical method to produce amino acids from woody biomass components. PMID:29712826

  20. Catalytic amino acid production from biomass-derived intermediates.

    PubMed

    Deng, Weiping; Wang, Yunzhu; Zhang, Sui; Gupta, Krishna M; Hülsey, Max J; Asakura, Hiroyuki; Liu, Lingmei; Han, Yu; Karp, Eric M; Beckham, Gregg T; Dyson, Paul J; Jiang, Jianwen; Tanaka, Tsunehiro; Wang, Ye; Yan, Ning

    2018-05-15

    Amino acids are the building blocks for protein biosynthesis and find use in myriad industrial applications including in food for humans, in animal feed, and as precursors for bio-based plastics, among others. However, the development of efficient chemical methods to convert abundant and renewable feedstocks into amino acids has been largely unsuccessful to date. To that end, here we report a heterogeneous catalyst that directly transforms lignocellulosic biomass-derived α-hydroxyl acids into α-amino acids, including alanine, leucine, valine, aspartic acid, and phenylalanine in high yields. The reaction follows a dehydrogenation-reductive amination pathway, with dehydrogenation as the rate-determining step. Ruthenium nanoparticles supported on carbon nanotubes (Ru/CNT) exhibit exceptional efficiency compared with catalysts based on other metals, due to the unique, reversible enhancement effect of NH 3 on Ru in dehydrogenation. Based on the catalytic system, a two-step chemical process was designed to convert glucose into alanine in 43% yield, comparable with the well-established microbial cultivation process, and therefore, the present strategy enables a route for the production of amino acids from renewable feedstocks. Moreover, a conceptual process design employing membrane distillation to facilitate product purification is proposed and validated. Overall, this study offers a rapid and potentially more efficient chemical method to produce amino acids from woody biomass components. Copyright © 2018 the Author(s). Published by PNAS.

  1. Catalytic amino acid production from biomass-derived intermediates

    DOE PAGES

    Deng, Weiping; Wang, Yunzhu; Zhang, Sui; ...

    2018-04-30

    Amino acids are the building blocks for protein biosynthesis and find use in myriad industrial applications including in food for humans, in animal feed, and as precursors for bio-based plastics, among others. However, the development of efficient chemical methods to convert abundant and renewable feedstocks into amino acids has been largely unsuccessful to date. To that end, here we report a heterogeneous catalyst that directly transforms lignocellulosic biomass-derived a-hydroxyl acids into a-amino acids, including alanine, leucine, valine, aspartic acid, and phenylalanine in high yields. The reaction follows a dehydrogenation-reductive amination pathway, with dehydrogenation as the rate-determining step. Ruthenium nanoparticles supportedmore » on carbon nanotubes (Ru/CNT) exhibit exceptional efficiency compared with catalysts based on other metals, due to the unique, reversible enhancement effect of NH 3 on Ru in dehydrogenation. Based on the catalytic system, a two-step chemical process was designed to convert glucose into alanine in 43% yield, comparable with the well-established microbial cultivation process, and therefore, the present strategy enables a route for the production of amino acids from renewable feedstocks. Moreover, a conceptual process design employing membrane distillation to facilitate product purification is proposed and validated. Overall, this study offers a rapid and potentially more efficient chemical method to produce amino acids from woody biomass components.« less

  2. Potential of endophytic fungus Phomopsis liquidambari for transformation and degradation of recalcitrant pollutant sinapic acid.

    PubMed

    Xie, Xing-Guang; Huang, Chun-Yan; Fu, Wan-Qiu; Dai, Chuan-Chao

    2016-03-01

    The biodegradation potential of sinapic acid, one of the most representative methoxy phenolic pollutants presented in industrial wastewater, was first studied using an endophytic fungus called Phomopsis liquidambari. This strain can effectively degrade sinapic acid in flasks and in soil and the possible biodegradation pathway was first systematically proposed on the basis of the metabolite production patterns and the identification of the metabolites by GC-MS and HPLC-MS. Sinapic acid was first transformed to 2,6-dimethoxy-4-vinylphenol that was further degraded via 4-hydroxy-3,5-dimethoxybenzaldehyde, syringic acid, gallic acid, and citric acid which involved in the continuous catalysis by phenolic acid decarboxylase, laccase, and gallic acid dioxygenase. Moreover, their activities and gene expression levels exhibited a 'cascade induction' response with the changes in metabolic product concentrations and the generation of fungal laccase significantly improved the degradation process. This study is the first report of an endophytic fungus that has great potential to degrade xenobiotic sinapic acid, and also provide a basis for practical application of endophytic fungus in the bioremediation of sinapic acid-contaminated industrial wastewater and soils. Copyright © 2015 The British Mycological Society. Published by Elsevier Ltd. All rights reserved.

  3. Fermentation Conditions that Affect Clavulanic Acid Production in Streptomyces clavuligerus: A Systematic Review.

    PubMed

    Ser, Hooi-Leng; Law, Jodi Woan-Fei; Chaiyakunapruk, Nathorn; Jacob, Sabrina Anne; Palanisamy, Uma Devi; Chan, Kok-Gan; Goh, Bey-Hing; Lee, Learn-Han

    2016-01-01

    The β-lactamase inhibitor, clavulanic acid is frequently used in combination with β-lactam antibiotics to treat a wide spectrum of infectious diseases. Clavulanic acid prevents drug resistance by pathogens against these β-lactam antibiotics by preventing the degradation of the β-lactam ring, thus ensuring eradication of these harmful microorganisms from the host. This systematic review provides an overview on the fermentation conditions that affect the production of clavulanic acid in the firstly described producer, Streptomyces clavuligerus. A thorough search was conducted using predefined terms in several electronic databases (PubMed, Medline, ScienceDirect, EBSCO), from database inception to June 30th 2015. Studies must involve wild-type Streptomyces clavuligerus, and full texts needed to be available. A total of 29 eligible articles were identified. Based on the literature, several factors were identified that could affect the production of clavulanic acid in S. clavuligerus. The addition of glycerol or other vegetable oils (e.g., olive oil, corn oil) could potentially affect clavulanic acid production. Furthermore, some amino acids such as arginine and ornithine, could serve as potential precursors to increase clavulanic acid yield. The comparison of different fermentation systems revealed that fed-batch fermentation yields higher amounts of clavulanic acid as compared to batch fermentation, probably due to the maintenance of substrates and constant monitoring of certain entities (such as pH, oxygen availability, etc.). Overall, these findings provide vital knowledge and insight that could assist media optimization and fermentation design for clavulanic acid production in S. clavuligerus.

  4. Engineering E. coli–E. coli cocultures for production of muconic acid from glycerol

    DOE PAGES

    Zhang, Haoran; Li, Zhengjun; Pereira, Brian; ...

    2015-09-15

    cis, cis-Muconic acid is an important chemical that can be biosynthesized from simple substrates in engineered microorganisms. Recently, it has been shown that engineering microbial cocultures is an emerging and promising approach for biochemical production. In this study, we aim to explore the potential of the E. coli–E. coli coculture system to use a single renewable carbon source, glycerol, for the production of value-added product cis, cis-muconic acid. As a result, two coculture engineering strategies were investigated. In the first strategy, an E. coli strain containing the complete biosynthesis pathway was co-cultivated with another E. coli strain containing only amore » heterologous intermediate-to-product biosynthetic pathway. In the second strategy, the upstream and downstream pathways were accommodated in two separate E. coli strains, each of which was dedicated to one portion of the biosynthesis process. Compared with the monoculture approach, both coculture engineering strategies improved the production significantly. Using a batch bioreactor, the engineered coculture achieved a 2 g/L muconic acid production with a yield of 0.1 g/g. In conclusion, our results demonstrate that coculture engineering is a viable option for producing muconic acid from glycerol. Moreover, microbial coculture systems are shown to have the potential for converting single carbon source to value-added products.« less

  5. PRODUCTION OF TRIFLUOROACETIC ACID

    DOEpatents

    Haworth, W.N.; Stacey, M.

    1949-07-19

    A method is given for the production of improved yields of trifluoroacetic acid. The compound is prepared by oxidizing m-aminobenzotrifluoride with an alkali metal or alkaline earth metal permanganate at a temperature in the range of 80 deg C to 100 deg C while dissolved ln a mixture of water with glacial acetic acid and/or trifluoroacetic acid. Preferably a mixture of water and trifluoroacetic acid ls used as the solvent.

  6. Influence of apple and citrus pectins, processed mango peels, a phenolic mango peel extract, and gallic Acid as potential feed supplements on in vitro total gas production and rumen methanogenesis.

    PubMed

    Geerkens, Christian Hubert; Schweiggert, Ralf Martin; Steingass, Herbert; Boguhn, Jeannette; Rodehutscord, Markus; Carle, Reinhold

    2013-06-19

    Several food processing byproducts were assessed as potential feed and feed supplements. Since their chemical composition revealed a high nutritional potential for ruminants, the Hohenheim in vitro gas test was used to investigate total gas, methane, and volatile fatty acid production as well as protozoal numbers after ruminal digestion of different substrate levels. Processing byproducts used were low- and high-esterified citrus and apple pectins, integral mango peels, and depectinized mango peels. In addition, the effect of a phenolic mango peel extract and pure gallic acid was investigated. The highest decrease in methane production (19%) was achieved by supplementing high levels of low-esterified citrus pectin to the hay-based diet. Interestingly, total gas production was not affected at the same time. Showing valuable nutritional potential, all byproducts exhibited, e.g., high metabolizable energy (11.9-12.8 MJ/kg DM). In conclusion, all byproducts, particularly low-esterified citrus pectin, revealed promising potential as feed and feed supplements.

  7. Microbial production of poly-γ-glutamic acid.

    PubMed

    Sirisansaneeyakul, Sarote; Cao, Mingfeng; Kongklom, Nuttawut; Chuensangjun, Chaniga; Shi, Zhongping; Chisti, Yusuf

    2017-09-05

    Poly-γ-glutamic acid (γ-PGA) is a natural, biodegradable and water-soluble biopolymer of glutamic acid. This review is focused on nonrecombinant microbial production of γ-PGA via fermentation processes. In view of its commercial importance, the emphasis is on L-glutamic acid independent producers (i.e. microorganisms that do not require feeding with the relatively expensive amino acid L-glutamic acid to produce γ-PGA), but glutamic acid dependent production is discussed for comparison. Strategies for improving production, reducing costs and using renewable feedstocks are discussed.

  8. Sampling the oxidative weathering products and the potentially acidic permafrost on Mars

    NASA Technical Reports Server (NTRS)

    Burns, Roger G.

    1988-01-01

    Large areas of Mars' surface are covered by oxidative weathering products containing ferric and sulfate ions having analogies to terrestrial gossans derived from sulfide mineralization associated with iron-rich basalts. Chemical weathering of such massive and disseminated pyrrhotite-pentlandite assemblages and host basaltic rocks in the Martian environment could have produced metastable gossaniferous phases (limonite containing poorly crystalline hydrated ferric sulfates and oxyhydroxides, clay silicates and opal). Underlying groundwater, now permafrost on Mars, may still be acidic due to incomplete buffering reactions by wall-rock alteration of unfractured host rock. Such acidic solutions stabilize temperature-sensitive complex ions and sols which flocculate to colloidal precipitates at elevated temperatures. Sampling procedures of Martian regolith will need to be designed bearing in mind that the frozen permafrost may be corrosive and be stabilizing unique complex ions and sols of Fe, Al, Mg, Ni and other minor elements.

  9. Cell immobilization for production of lactic acid biofilms do it naturally.

    PubMed

    Dagher, Suzanne F; Ragout, Alicia L; Siñeriz, Faustino; Bruno-Bárcena, José M

    2010-01-01

    Interest in natural cell immobilization or biofilms for lactic acid fermentation has developed considerably over the last few decades. Many studies report the benefits associated with biofilms as industrial methods for food production and for wastewater treatment, since the formation represents a protective means of microbial growth offering survival advantages to cells in toxic environments. The formation of biofilms is a natural process in which microbial cells adsorb to a support without chemicals or polymers that entrap the cells and is dependent on the reactor environment, microorganism, and characteristics of the support. These unique characteristics enable biofilms to cause chronic infections, disease, food spoilage, and devastating effects as in microbial corrosion. Their distinct resistance to toxicity, high biomass potential, and improved stability over cells in suspension make biofilms a good tool for improving the industrial economics of biological lactic acid production. Lactic acid bacteria and specific filamentous fungi are the main sources of biological lactic acid. Over the past two decades, studies have focused on improving the lactic acid volumetric productivity through reactor design development, new support materials, and improvements in microbial production strains. To illustrate the operational designs applied to the natural immobilization of lactic acid producing microorganisms, this chapter presents the results of a search for optimum parameters and how they are affected by the physical, chemical, and biological variables of the process. We will place particular emphasis upon the relationship between lactic acid productivity attained by various types of reactors, supports, media formulations, and lactic acid producing microorganisms. Copyright (c) 2010 Elsevier Inc. All rights reserved.

  10. Production of hydroxycinnamoyl-shikimates and chlorogenic acid in Escherichia coli: production of hydroxycinnamic acid conjugates

    PubMed Central

    2013-01-01

    Background Hydroxycinnamates (HCs) are mainly produced in plants. Caffeic acid (CA), p-coumaric acid (PA), ferulic acid (FA) and sinapic acid (SA) are members of the HC family. The consumption of HC by human might prevent cardiovascular disease and some types of cancer. The solubility of HCs is increased through thioester conjugation to various compounds such as quinic acid, shikimic acid, malic acid, anthranilic acid, and glycerol. Although hydroxycinnamate conjugates can be obtained from diverse plant sources such as coffee, tomato, potato, apple, and sweet potato, some parts of the world have limited availability to these compounds. Thus, there is growing interest in producing HC conjugates as nutraceutical supplements. Results Hydroxycinnamoyl transferases (HCTs) including hydroxycinnamate-CoA shikimate transferase (HST) and hydroxycinnamate-CoA quinate transferase (HQT) were co-expressed with 4-coumarateCoA:ligase (4CL) in Escherichia coli cultured in media supplemented with HCs. Two hydroxycinnamoyl conjugates, p-coumaroyl shikimates and chlorogenic acid, were thereby synthesized. Total 29.1 mg/L of four different p-coumaroyl shikimates (3-p-coumaroyl shikimate, 4-p-coumaroyl shikimate, 3,4-di-p-coumaroyl shikimate, 3,5-di-p-coumaroyl shikimate, and 4,5-di-p-coumaroyl shikimate) was obtained and 16 mg/L of chlorogenic acid was synthesized in the wild type E. coli strain. To increase the concentration of endogenous acceptor substrates such as shikimate and quinate, the shikimate pathway in E. coli was engineered. A E. coli aroL and aroK gene were mutated and the resulting mutants were used for the production of p-coumaroyl shikimate. An E. coli aroD mutant was used for the production of chlorogenic acid. We also optimized the vector and cell concentration optimization. Conclusions To produce p-coumaroyl-shikimates and chlorogenic acid in E. coli, several E. coli mutants (an aroD mutant for chlorogenic acid production; an aroL, aroK, and aroKL mutant for p

  11. Fatty acid synthesis in Escherichia coli and its applications towards the production of fatty acid based biofuels

    PubMed Central

    2014-01-01

    The idea of renewable and regenerative resources has inspired research for more than a hundred years. Ideally, the only spent energy will replenish itself, like plant material, sunlight, thermal energy or wind. Biodiesel or ethanol are examples, since their production relies mainly on plant material. However, it has become apparent that crop derived biofuels will not be sufficient to satisfy future energy demands. Thus, especially in the last decade a lot of research has focused on the production of next generation biofuels. A major subject of these investigations has been the microbial fatty acid biosynthesis with the aim to produce fatty acids or derivatives for substitution of diesel. As an industrially important organism and with the best studied microbial fatty acid biosynthesis, Escherichia coli has been chosen as producer in many of these studies and several reviews have been published in the fields of E. coli fatty acid biosynthesis or biofuels. However, most reviews discuss only one of these topics in detail, despite the fact, that a profound understanding of the involved enzymes and their regulation is necessary for efficient genetic engineering of the entire pathway. The first part of this review aims at summarizing the knowledge about fatty acid biosynthesis of E. coli and its regulation, and it provides the connection towards the production of fatty acids and related biofuels. The second part gives an overview about the achievements by genetic engineering of the fatty acid biosynthesis towards the production of next generation biofuels. Finally, the actual importance and potential of fatty acid-based biofuels will be discussed. PMID:24405789

  12. Abscisic Acid Accumulation Maintains Maize Primary Root Elongation at Low Water Potentials by Restricting Ethylene Production1

    PubMed Central

    Spollen, William G.; LeNoble, Mary E.; Samuels, Timmy D.; Bernstein, Nirit; Sharp, Robert E.

    2000-01-01

    Previous work showed that primary root elongation in maize (Zea mays L.) seedlings at low water potentials (ψw) requires the accumulation of abscisic acid (ABA) (R.E. Sharp, Y. Wu, G.S. Voetberg, I.N. Saab, M.E. LeNoble [1994] J Exp Bot 45: 1743–1751). The objective of the present study was to determine whether the inhibition of elongation in ABA-deficient roots is attributable to ethylene. At a ψw of −1.6 MPa, inhibition of root elongation in dark-grown seedlings treated with fluridone to impose ABA deficiency was largely prevented with two inhibitors of ethylene synthesis (aminooxyacetic acid and aminoethoxyvinylglycine) and one inhibitor of ethylene action (silver thiosulfate). The fluridone treatment caused an increase in the rate of ethylene evolution from intact seedlings. This effect was completely prevented with aminooxyacetic acid and also when ABA was supplied at a concentration that restored the ABA content of the root elongation zone and the root elongation rate. Consistent results were obtained when ABA deficiency was imposed using the vp5 mutant. Both fluridone-treated and vp5 roots exhibited additional morphological symptoms of excess ethylene. The results demonstrate that an important role of ABA accumulation in the maintenance of root elongation at low ψw is to restrict ethylene production. PMID:10712561

  13. Bioactivity and biotechnological production of punicic acid.

    PubMed

    Holic, Roman; Xu, Yang; Caldo, Kristian Mark P; Singer, Stacy D; Field, Catherine J; Weselake, Randall J; Chen, Guanqun

    2018-04-01

    Punicic acid (PuA; 18: 3Δ 9cis,11trans,13cis ) is an unusual 18-carbon fatty acid bearing three conjugated double bonds. It has been shown to exhibit a myriad of beneficial bioactivities including anti-cancer, anti-diabetes, anti-obesity, antioxidant, and anti-inflammatory properties. Pomegranate (Punica granatum) seed oil contains approximately 80% PuA and is currently the major natural source of this remarkable fatty acid. While both PuA and pomegranate seed oil have been used as functional ingredients in foods and cosmetics for some time, their value in pharmaceutical/medical and industrial applications are presently under further exploration. Unfortunately, the availability of PuA is severely limited by the low yield and unstable supply of pomegranate seeds. In addition, efforts to produce PuA in transgenic crops have been limited by a relatively low content of PuA in the resulting seed oil. The production of PuA in engineered microorganisms with modern fermentation technology is therefore a promising and emerging method with the potential to resolve this predicament. In this paper, we provide a comprehensive review of this unusual fatty acid, covering topics ranging from its natural sources, biosynthesis, extraction and analysis, bioactivity, health benefits, and industrial applications, to recent efforts and future perspectives on the production of PuA in engineered plants and microorganisms.

  14. Production of a conjugated fatty acid by Bifidobacterium breve LMC520 from α-linolenic acid: conjugated linolenic acid (CLnA).

    PubMed

    Park, Hui Gyu; Cho, Hyung Taek; Song, Myoung-Chong; Kim, Sang Bum; Kwon, Eung Gi; Choi, Nag Jin; Kim, Young Jun

    2012-03-28

    This study was performed to characterize natural CLnA isomer production by Bifidobacterium breve LMC520 of human origin in comparison to conjugated linoleic acid (CLA) production. B. breve LMC520 was found to be highly active in terms of CLnA production, of which the major portion was identified as cis-9,trans-11,cis-15 CLnA isomer by GC-MS and NMR analysis. B. breve LMC520 was incubated for 48 h using MRS medium (containing 0.05% L-cysteine · HCl) under different environmental conditions such as atmosphere, pH, and substrate concentration. The high conversion rate of α-linolenic acid (α-LNA) to CLnA (99%) was retained up to 2 mM α-LNA, and the production was proportionally increased nearly 7-fold with 8 mM by the 6 h of incubation under anaerobic conditions at a wide range of pH values (between 5 and 9). When α-LNA was compared with linoleic acid (LA) as a substrate for isomerization by B. breve LMC520, the conversion of α-LNA was higher than that of LA. These results demonstrated that specific CLnA isomer could be produced through active bacterial conversion at an optimized condition. Because many conjugated octadecatrienoic acids in nature are shown to play many positive roles, the noble isomer found in this study has potential as a functional source.

  15. Integrated production of cellulosic bioethanol and succinic acid from rapeseed straw after dilute-acid pretreatment.

    PubMed

    Kuglarz, Mariusz; Alvarado-Morales, Merlin; Dąbkowska, Katarzyna; Angelidaki, Irini

    2018-05-29

    The aim of this study was to develop an integrated biofuel (cellulosic bioethanol) and biochemical (succinic acid) production process from rapeseed straw after dilute-acid pretreatment. Rapeseed straw pretreatment at 20% (w/v) solid loading and subsequent hydrolysis with Cellic® CTec2 resulted in high glucose yield (80%) and ethanol output (122-125 kg of EtOH/Mg of rapeseed straw). Supplementation the enzymatic process with 10% dosage of endoxylanases (Cellic® HTec2) reduced the hydrolysis time required to achieve the maximum glucan conversion by 44-46% and increased the xylose yield by 10% compared to the process with Cellic® CTec2. Significantly higher amounts of succinic acid were produced after fermentation of pretreatment liquor (48 kg/Mg of rapeseed straw, succinic acid yield: 60%) compared to fermentation of xylose-rich residue after ethanol production (35-37 kg/Mg of rapeseed straw, succinic yield: 68-71%). Results obtained in this study clearly proved the biorefinery potential of rapeseed straw. Copyright © 2018 Elsevier Ltd. All rights reserved.

  16. Effects of rare sugar D-allulose on acid production and probiotic activities of dairy lactic acid bacteria.

    PubMed

    Kimoto-Nira, H; Moriya, N; Hayakawa, S; Kuramasu, K; Ohmori, H; Yamasaki, S; Ogawa, M

    2017-07-01

    It has recently been reported that the rare sugar d-allulose has beneficial effects, including the suppression of postprandial blood glucose elevation in humans, and can be substituted for sucrose as a low-calorie food ingredient. To examine the applications of d-allulose in the dairy industry, we investigated the effects of d-allulose on the acid production of 8 strains of yogurt starter (Lactobacillus delbrueckii ssp. bulgaricus and Streptococcus thermophilus) and 4 strains of lactococci, including potential probiotic candidates derived from dairy products. Acid production by 2 L. delbrueckii ssp. bulgaricus yogurt starter strains in milk was suppressed by d-allulose, but this phenomenon was also observed in some strains with another sugar (xylose), a sugar alcohol (sorbitol), or both. In contrast, among the dairy probiotic candidates, Lactococcus lactis H61, which has beneficial effects for human skin when drunk as part of fermented milk, was the only strain that showed suppression of acid production in the presence of d-allulose. Strain H61 did not metabolize d-allulose. We did not observe suppression of acid production by strain H61 with the addition of xylose or sorbitol, and xylose and sorbitol were not metabolized by strain H61. The acid production of strain H61 after culture in a constituted medium (tryptone-yeast extract-glucose broth) was also suppressed with the addition of d-allulose, but growth efficiency and sugar fermentation style were not altered. Probiotic activities-such as the angiotensin-converting enzyme inhibitory activity of H61-fermented milk and the superoxide dismutase activity of H61 cells grown in tryptone-yeast extract-glucose broth-were not affected by d-allulose. d-Allulose may suppress acid production in certain lactic acid bacteria without altering their probiotic activity. It may be useful for developing new probiotic dairy products from probiotic strains such as Lactococcus lactis H61. Copyright © 2017 American Dairy Science

  17. Isolation of lactic acid bacteria with potential protective culture characteristics from fruits

    NASA Astrophysics Data System (ADS)

    Hashim, Nurul Huda; Sani, Norrakiah Abdullah

    2015-09-01

    Lactic acid bacteria are also known as beneficial microorganisms abundantly found in fermented food products. In this study, lactic acid bacteria were isolated from fresh cut fruits obtained from local markets. Throughout the isolation process from 11 samples of fruits, 225 presumptive lactic acid bacteria were isolated on MRS agar medium. After catalase and oxidase tests, 149 resulted to fit the characteristics of lactic acid bacteria. Further identification using Gram staining was conducted to identify the Gram positive bacteria. After this confirmation, the fermentation characteristics of these isolates were identified. It was found that 87 (58.4%) isolates were heterofermentative, while the rest of 62 (41.6%) are homofermentative lactic acid bacteria. Later, all these isolates were investigated for the ability to inhibit growth of Staphylococcus aureus using agar spot assay method. Seven (4.7%) isolates showed strong antagonistic capacity, while 127 (85.2%) and 8 (5.4%) isolates have medium and weak antagonistic capacity, respectively. The other 7 (4.7%) isolates indicated to have no antagonistic effect on S. aureus. Results support the potential of LAB isolated in this study which showed strong antagonistic activity against S. aureus may be manipulated to become protective cultures in food products. While the homofermentative or heterofermentative LAB can be utilized in fermentation of food and non-food products depending on the by-products required during the fermentation.

  18. Production of Succinic Acid from Citric Acid and Related Acids by Lactobacillus Strains

    PubMed Central

    Kaneuchi, Choji; Seki, Masako; Komagata, Kazuo

    1988-01-01

    A number of Lactobacillus strains produced succinic acid in de Man-Rogosa-Sharpe broth to various extents. Among 86 fresh isolates from fermented cane molasses in Thailand, 30 strains (35%) produced succinic acid; namely, 23 of 39 Lactobacillus reuteri strains, 6 of 18 L. cellobiosus strains, and 1 of 6 unidentified strains. All of 10 L. casei subsp. casei strains, 5 L. casei subsp. rhamnosus strains, 6 L. mali strains, and 2 L. buchneri strains did not produce succinic acid. Among 58 known strains including 48 type strains of different Lactobacillus species, the strains of L. acidophilus, L. crispatus, L. jensenii, and L. parvus produced succinic acid to the same extent as the most active fresh isolates, and those of L. alimentarius, L. collinoides, L. farciminis, L. fructivorans (1 of 2 strains tested), L. malefermentans, and L. reuteri were also positive, to lesser extents. Diammonium citrate in de Man-Rogosa-Sharpe broth was determined as a precursor of the succinic acid produced. Production rates were about 70% on a molar basis with two fresh strains tested. Succinic acid was also produced from fumaric and malic acids but not from dl-isocitric, α-ketoglutaric, and pyruvic acids. The present study is considered to provide the first evidence on the production of succinic acid, an important flavoring substance in dairy products and fermented beverages, from citrate by lactobacilli. PMID:16347795

  19. Production of succinic Acid from citric Acid and related acids by lactobacillus strains.

    PubMed

    Kaneuchi, C; Seki, M; Komagata, K

    1988-12-01

    A number of Lactobacillus strains produced succinic acid in de Man-Rogosa-Sharpe broth to various extents. Among 86 fresh isolates from fermented cane molasses in Thailand, 30 strains (35%) produced succinic acid; namely, 23 of 39 Lactobacillus reuteri strains, 6 of 18 L. cellobiosus strains, and 1 of 6 unidentified strains. All of 10 L. casei subsp. casei strains, 5 L. casei subsp. rhamnosus strains, 6 L. mali strains, and 2 L. buchneri strains did not produce succinic acid. Among 58 known strains including 48 type strains of different Lactobacillus species, the strains of L. acidophilus, L. crispatus, L. jensenii, and L. parvus produced succinic acid to the same extent as the most active fresh isolates, and those of L. alimentarius, L. collinoides, L. farciminis, L. fructivorans (1 of 2 strains tested), L. malefermentans, and L. reuteri were also positive, to lesser extents. Diammonium citrate in de Man-Rogosa-Sharpe broth was determined as a precursor of the succinic acid produced. Production rates were about 70% on a molar basis with two fresh strains tested. Succinic acid was also produced from fumaric and malic acids but not from dl-isocitric, alpha-ketoglutaric, and pyruvic acids. The present study is considered to provide the first evidence on the production of succinic acid, an important flavoring substance in dairy products and fermented beverages, from citrate by lactobacilli.

  20. Metabolic engineering of Clostridium acetobutylicum for enhanced production of butyric acid.

    PubMed

    Jang, Yu-Sin; Woo, Hee Moon; Im, Jung Ae; Kim, In Ho; Lee, Sang Yup

    2013-11-01

    Clostridium acetobutylicum has been considered as an attractive platform host for biorefinery due to its metabolic diversity. Considering its capability to overproduce butanol through butyrate, it was thought that butyric acid can also be efficiently produced by this bacterium through metabolic engineering. The pta-ctfB-deficient C. acetobutylicum CEKW, in which genes encoding phosphotransacetylase and CoA-transferase were knocked out, was assessed for its potential as a butyric acid producer in fermentations with four controlled pH values at 5.0, 5.5, 6.0, and 6.4. Butyric acid could be best produced by fermentation of the CEKW at pH 6.0, resulting in the highest titer of 26.6 g/l, which is 6.4 times higher than that obtained with the wild type. However, due to the remaining solventogenic ability of the CEKW, 3.6 g/l solvents were also produced. Thus, the CEKW was further engineered by knocking out the adhE1-encoding aldehyde/alcohol dehydrogenase to prevent solvent production. Batch fermentation of the resulting C. acetobutylicum HCEKW at pH 6.0 showed increased butyric acid production to 30.8 g/l with a ratio of butyric-to-acetic acid (BA/AA) of 6.6 g/g and a productivity of 0.72 g/l/h from 86.9 g/l glucose, while negligible solvent (0.8 g/l ethanol only) was produced. The butyric acid titer, BA/AA ratio, and productivity obtained in this study were the highest values reported for C. acetobutylicum, and the BA/AA ratio and productivity were also comparable to those of native butyric acid producer Clostridium tyrobutyricum. These results suggested that the simultaneous deletion of the pta-ctfB-adhE1 in C. acetobutylicum resulted in metabolic switch from biphasic to acidogenic fermentation, which enhanced butyric acid production.

  1. Mannose and galactose as substrates for production of itaconic acid by Aspergillus terreus

    USDA-ARS?s Scientific Manuscript database

    Itaconic acid (IA), an unsaturated 5-carbon dicarboxylic acid, is a building block platform chemical that is currently produced industrially from glucose by fermentation with Aspergillus terreus. Softwood has the potential to serve as low cost source of sugars for its production. Effective utilizati...

  2. Homofermentative production of optically pure L-lactic acid from xylose by genetically engineered Escherichia coli B.

    PubMed

    Zhao, Jinfang; Xu, Liyuan; Wang, Yongze; Zhao, Xiao; Wang, Jinhua; Garza, Erin; Manow, Ryan; Zhou, Shengde

    2013-06-07

    Polylactic acid (PLA), a biodegradable polymer, has the potential to replace (at least partially) traditional petroleum-based plastics, minimizing "white pollution". However, cost-effective production of optically pure L-lactic acid is needed to achieve the full potential of PLA. Currently, starch-based glucose is used for L-lactic acid fermentation by lactic acid bacteria. Due to its competition with food resources, an alternative non-food substrate such as cellulosic biomass is needed for L-lactic acid fermentation. Nevertheless, the substrate (sugar stream) derived from cellulosic biomass contains significant amounts of xylose, which is unfermentable by most lactic acid bacteria. However, the microorganisms that do ferment xylose usually carry out heterolactic acid fermentation. As a result, an alternative strain should be developed for homofermentative production of optically pure L-lactic acid using cellulosic biomass. In this study, an ethanologenic Escherichia coli strain, SZ470 (ΔfrdBC ΔldhA ΔackA ΔpflB ΔpdhR ::pflBp6-acEF-lpd ΔmgsA), was reengineered for homofermentative production of L-lactic acid from xylose (1.2 mole xylose = > 2 mole L-lactic acid), by deleting the alcohol dehydrogenase gene (adhE) and integrating the L-lactate dehydrogenase gene (ldhL) of Pediococcus acidilactici. The resulting strain, WL203, was metabolically evolved further through serial transfers in screw-cap tubes containing xylose, resulting in the strain WL204 with improved anaerobic cell growth. When tested in 70 g L-1 xylose fermentation (complex medium), WL204 produced 62 g L-1 L-lactic acid, with a maximum production rate of 1.631 g L-1 h-1 and a yield of 97% based on xylose metabolized. HPLC analysis using a chiral column showed that an L-lactic acid optical purity of 99.5% was achieved by WL204. These results demonstrated that WL204 has the potential for homofermentative production of L-lactic acid using cellulosic biomass derived substrates, which contain a

  3. Acid production potentials of massive sulfide minerals and lead-zinc mine tailings: a medium-term study.

    PubMed

    Çelebi, Emin Ender; Öncel, Mehmet Salim; Kobya, Mehmet

    2018-01-01

    Weathering of sulfide minerals is a principal source of acid generation. To determine acid-forming potentials of sulfide-bearing materials, two basic approaches named static and kinetic tests are available. Static tests are short-term, and easily undertaken within a few days and in a laboratory. In contrast, kinetic tests are long-term procedures and mostly carried out on site. In this study, experiments were conducted over a medium-term period of 2 months, not as short as static tests and also not as long as kinetic tests. As a result, pH and electrical conductivity oscillations as a function of time, acid-forming potentials and elemental contents of synthetically prepared rainwater leachates of massive sulfides and sulfide-bearing lead-zinc tailings from abandoned and currently used deposition areas have been determined. Although the lowest final pH of 2.70 was obtained in massive pyrite leachate, massive chalcopyrite leachate showed the highest titrable acidity of 1.764 g H 2 SO 4 /L. On the other hand, a composite of currently deposited mine tailings showed no acidic characteristic with a final pH of 7.77. The composite abandoned mine tailing leachate had a final pH of 6.70, close to the final pH of massive galena and sphalerite leachates, and produced a slight titrable acidity of 0.130 g H 2 SO 4 /L.

  4. Isolation and molecular characterization of Thraustochytrium strain isolated from Antarctic Peninsula and its biotechnological potential in the production of fatty acids.

    PubMed

    Caamaño, Esteban; Loperena, Lyliam; Hinzpeter, Ivonne; Pradel, Paulina; Gordillo, Felipe; Corsini, Gino; Tello, Mario; Lavín, Paris; González, Alex R

    Thraustochytrids are unicellular protists belonging to the Labyrinthulomycetes class, which are characterized by the presence of a high lipid content that could replace conventional fatty acids. They show a wide geographic distribution, however their diversity in the Antarctic Region is rather scarce. The analysis based on the complete sequence of 18S rRNA gene showed that strain 34-2 belongs to the species Thraustochytrium kinnei, with 99% identity. The total lipid profile shows a wide range of saturated fatty acids with abundance of palmitic acid (16:0), showing a range of 16.1-19.7%. On the other hand, long-chain polyunsaturated fatty acids, mainly docosahexaenoic acid and eicosapentaenoic acid are present in a range of 24-48% and 6.1-9.3%, respectively. All factors analyzed in cells (biomass, carbon consumption and lipid content) changed with variations of culture temperature (10°C and 25°C). The growth in glucose at a temperature of 10°C presented the most favorable conditions to produce omega-3fatty acid. This research provides the identification and characterization of a Thraustochytrids strain, with a total lipid content that presents potential applications in the production of nutritional supplements and as well biofuels. Copyright © 2017 Sociedade Brasileira de Microbiologia. Published by Elsevier Editora Ltda. All rights reserved.

  5. Growth and fatty acid characterization of microalgae isolated from municipal waste-treatment systems and the potential role of algal-associated bacteria in feedstock production

    PubMed Central

    Stemmler, Kevin; Massimi, Rebecca

    2016-01-01

    Much research has focused on growing microalgae for biofuel feedstock, yet there remain concerns about the feasibility of freshwater feedstock systems. To reduce cost and improve environmental sustainability, an ideal microalgal feedstock system would be fed by municipal, agricultural or industrial wastewater as a main source of water and nutrients. Nonetheless, the microalgae must also be tolerant of fluctuating wastewater quality, while still producing adequate biomass and lipid yields. To address this problem, our study focused on isolating and characterizing microalgal strains from three municipal wastewater treatment systems (two activated sludge and one aerated-stabilization basin systems) for their potential use in biofuel feedstock production. Most of the 19 isolates from wastewater grew faster than two culture collection strains under mixotrophic conditions, particularly with glucose. The fastest growing wastewater strains included the genera Chlorella and Dictyochloris. The fastest growing microalgal strains were not necessarily the best lipid producers. Under photoautotrophic and mixotrophic growth conditions, single strains of Chlorella and Scenedesmus each produced the highest lipid yields, including those most relevant to biodiesel production. A comparison of axenic and non-axenic versions of wastewater strains showed a notable effect of commensal bacteria on fatty acid composition. Strains grown with bacteria tended to produce relatively equal proportions of saturated and unsaturated fatty acids, which is an ideal lipid blend for biodiesel production. These results not only show the potential for using microalgae isolated from wastewater for growth in wastewater-fed feedstock systems, but also the important role that commensal bacteria may have in impacting the fatty acid profiles of microalgal feedstock. PMID:26989618

  6. Direct production of biodiesel from high-acid value Jatropha oil with solid acid catalyst derived from lignin

    PubMed Central

    2011-01-01

    Background Solid acid catalyst was prepared from Kraft lignin by chemical activation with phosphoric acid, pyrolysis and sulfuric acid. This catalyst had high acid density as characterized by scanning electron microscope (SEM), energy-dispersive x-ray spectrometry (EDX) and Brunauer, Emmett, and Teller (BET) method analyses. It was further used to catalyze the esterification of oleic acid and one-step conversion of non-pretreated Jatropha oil to biodiesel. The effects of catalyst loading, reaction temperature and oil-to-methanol molar ratio, on the catalytic activity of the esterification were investigated. Results The highest catalytic activity was achieved with a 96.1% esterification rate, and the catalyst can be reused three times with little deactivation under optimized conditions. Biodiesel production from Jatropha oil was studied under such conditions. It was found that 96.3% biodiesel yield from non-pretreated Jatropha oil with high-acid value (12.7 mg KOH/g) could be achieved. Conclusions The catalyst can be easily separated for reuse. This single-step process could be a potential route for biodiesel production from high-acid value oil by simplifying the procedure and reducing costs. PMID:22145867

  7. The allelochemical trans-cinnamic acid stimulates salicylic acid production and galactose pathway in maize leaves: A potential mechanism of stress tolerance.

    PubMed

    Araniti, Fabrizio; Lupini, Antonio; Mauceri, Antonio; Zumbo, Antonino; Sunseri, Francesco; Abenavoli, Maria Rosa

    2018-05-05

    In this study, the effects (5 days) of the secondary metabolite trans-cinnamic acid on maize leaves (Zea mays L.), through a physiological and an untargeted metabolomic approach, were evaluated. A reduction in leaf growth and development accompanied by a decrease in protein content was observed in treated seedlings. Besides, trans-cinnamic acid stimulated the photosynthetic machinery with a significant increment in pigment content (chlorophyll a, b and carotenoids), a stimulation of the light adapted PSII efficiency (ɸ II ) as well as the chlorophyll a fluorescence (Y NO ), the apparent electron transport rate, and the regulated dissipation of the energy (Y NPQ ). By contrast, the dark adapted PSII parameter (Fv/Fm) was not affected suggesting that no physical damages to the antenna complex were caused by trans-cinnamic acid. These results suggested that maize seedlings were experiencing a stress but, at the same time, were able to cope with it. This hypothesis was confirmed by both the increment in benzoic and salicylic acids, important molecules involved in stress response, and the metabolomic results, which pointed out that the seedlings are directing their metabolism towards galactose production modulating its pathway, which is pivotal for the production of the antioxidant compound ascorbic acid (ASA). Indeed, in treated plants, a significant increment in total ASA content (28%) was observed. The results suggested that the main strategy adopted by plants to cope with trans-cinnamic-induced stress consisted in the modulation of their metabolism in order to increase the total ASA and carotenoids concentration, radical scavenging species. Copyright © 2018 Elsevier Masson SAS. All rights reserved.

  8. Indoleacetic acid production and plant growth promoting potential of bacterial endophytes isolated from rice (Oryza sativa L.) seeds.

    PubMed

    Shahzad, Raheem; Waqas, Muhammad; Khan, Abdul Latif; Al-Hosni, Khadija; Kang, Sang-Mo; Seo, Chang-Woo; Lee, In-Jung

    2017-06-01

    Bacterial endophytes from the phyllosphere and rhizosphere have been used to produce bioactive metabolites and to promote plant growth. However, little is known about the endophytes residing in seeds. This study aimed to isolate and identify seed-borne bacterial endophytes from rice and elucidate their potential for phytohormone production and growth enhancement. The isolated endophytes included Micrococcus yunnanensis RWL-2, Micrococcus luteus RWL-3, Enterobacter soli RWL-4, Leclercia adecarboxylata RWL-5, Pantoea dispersa RWL-6, and Staphylococcus epidermidis RWL-7, which were identified using 16S rRNA sequencing and phylogenetic analysis. These strains were analyzed for indoleacetic acid (IAA) production by using GC-MS and IAA was found in the range of 11.50 ± 0.77 μg ml -1 to 38.80 ± 1.35 μg ml -1 . We also assessed the strains for plant growth promoting potential because these isolates were able to produce IAA in pure culture. Most of the growth attributes of rice plants (shoot and root length, fresh and dry biomass, and chlorophyll content) were significantly increased by bacterial endophytes compared to the controls. These results show that IAA producing bacterial endophytes can improve hostplant growth traits and can be used as bio-fertilizers.

  9. Environmental evaluation of eicosapentaenoic acid production by Phaeodactylum tricornutum.

    PubMed

    Pérez-López, Paula; González-García, Sara; Allewaert, Céline; Verween, Annick; Murray, Patrick; Feijoo, Gumersindo; Moreira, Ma Teresa

    2014-01-01

    Polyunsaturated fatty acids (PUFAs) play an important role in human health. Due to the increased market demand, the production of PUFAs from potential alternative sources such as microalgae is receiving increased interest. The aim of this study was to perform a life cycle assessment (LCA) of the biotechnological production of eicosapentaenoic acid (EPA) from the marine diatom Phaeodactylum tricornutum, followed by the identification of avenues to improve its environmental profile. The LCA tackles two production schemes of P. tricornutum PUFAs with an EPA content of 36%: lab and pilot scales. The results at lab scale show that both the electricity requirements and the production of the extraction agent (chloroform) have significant influence on the life cycle environmental performance of microalgal EPA production. An alternative method based on hexane was proposed to replace chloroform and environmental benefits were identified. Regarding the production of EPA at pilot scale, three main environmental factors were identified: the production of the nitrogen source required for microalgae growing, the transport activities and electricity requirements. Improvement alternatives were proposed and discussed concerning: a) the use of nitrogen based fertilizers, b) the valorization of the residual algal paste as soil conditioner and, c) the anaerobic digestion of the residual algal paste for bioenergy production. Encouraging environmental benefits could be achieved if sodium nitrate was substituted by urea, calcium nitrate or ammonium nitrate, regardless the category under assessment. In contrast, minor improvement was found when valorizing the residual algal paste as mineral fertilizer, due to its overall low content in N and P. Concerning the biogas production from the anaerobic digestion, the improvement on the environmental profile was also limited due to the discrepancy between the potential energy production from the algal paste and the high electricity requirements in

  10. Scaleable production and separation of fermentation-derived acetic acid. Final CRADA report.

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

    Snyder, S. W.; Energy Systems

    2010-02-08

    (4) Moderate ammonia flux. The advantages of producing acetic acid by fermentation include its appropriateness for small-scale production, lower cost feedstocks, low energy membrane-based purification, and lower temperature and pressure requirements. Potential energy savings of using fermentation are estimated to be approximately 14 trillion Btu by 2020 from a reduction in natural gas use. Decreased transportation needs with regional plants will eliminate approximately 200 million gallons of diesel consumption, for combined savings of 45 trillion Btu. If the fermentation process captures new acetic acid production, savings could include an additional 5 trillion Btu from production and 7 trillion Btu from transportation energy.« less

  11. Pediatric poisonings from household products: hydrofluoric acid and methacrylic acid.

    PubMed

    Perry, H E

    2001-04-01

    Household products continue to be a cause of poisoning morbibidity and mortality. Young children frequently are exposed to cleaning products and cosmetics in the course of exploring their environment. Most of these exposures are insignificant, but some result in death or permanent disability. This review discusses two products that have been responsible for serious injury and death in children: hydrofluoric acid and methacrylic acid. It also discusses federal initiatives designed to protect children from these and other household hazards.

  12. Parabanic acid is the singlet oxygen specific oxidation product of uric acid.

    PubMed

    Iida, Sayaka; Ohkubo, Yuki; Yamamoto, Yorihiro; Fujisawa, Akio

    2017-11-01

    Uric acid quenches singlet oxygen physically or reacts with it, but the oxidation product has not been previously characterized. The present study determined that the product is parabanic acid, which was confirmed by LC/TOFMS analysis. Parabanic acid was stable at acidic pH (<5.0), but hydrolyzed to oxaluric acid at neutral or alkaline pH. The total yields of parabanic acid and oxaluric acid based on consumed uric acid were ~100% in clean singlet oxygen production systems such as UVA irradiation of Rose Bengal and thermal decomposition of 3-(1,4-dihydro-1,4-epidioxy-4-methyl-1-naphthyl)propionic acid. However, the ratio of the amount of uric acid consumed to the total amount of singlet oxygen generated was less than 1/180, indicating that most of the singlet oxygen was physically quenched. The total yields of parabanic acid and oxaluric acid were high in the uric acid oxidation systems with hydrogen peroxide plus hypochlorite or peroxynitrite. They became less than a few percent in peroxyl radical-, hypochlorite- or peroxynitrite-induced oxidation of uric acid. These results suggest that parabanic acid could be an in vivo probe of singlet oxygen formation because of the wide distribution of uric acid in human tissues and extracellular spaces. In fact, sunlight exposure significantly increased human skin levels of parabanic acid.

  13. Characterization of the newly isolated ω-oxidizing yeast Candida sorbophila DS02 and its potential applications in long-chain dicarboxylic acid production.

    PubMed

    Lee, Heeseok; Sugiharto, Yohanes Eko Chandra; Lee, Seunghoon; Park, Gyuyeon; Han, Changpyo; Jang, Hyeran; Jeon, Wooyoung; Park, Heejoon; Ahn, Jungoh; Kang, Kyungbo; Lee, Hongwoen

    2017-08-01

    α, ω-Dicarboxylic acids (DCAs) are multipurpose chemicals widely used in polymers, perfumes, plasticizers, lubricants, and adhesives. The biotransformation of DCAs from alkanes and fatty acids by microorganisms has attracted recent interest, since synthesis via chemical oxidation causes problems in terms of the environment and safety. We isolated an ω-oxidizing yeast from a wastewater disposal facility of a petrochemical factory by chemostat enrichment culture. The haploid strain identified as Candida sorbophila DS02 grew on glucose and dodecane, exhibiting greater cell shrinkage on the latter. In flask cultures with mixed alkanes (C10-16) and fatty acid methyl esters (C10-16), DS02 used mixed alkanes simultaneously unlike Candida tropicalis and Yarrowia lipolytica and showed high substrate resistance. In flask cultures with acrylic acid-a known inhibitor of β-oxidation-DS02 produced 0.28 g/l dodecanedioic acid (DDDA) from dodecane, similar to wild-type C. tropicalis ATCC 20336. In fed-batch fermentation, DS02 produced 9.87 g/l DDDA, which was 5.7-fold higher than wild-type C. tropicalis. These results suggest that C. sorbophila strain DS02 has potential applications for the large-scale production of DCA.

  14. Prescription Omega-3 Fatty Acid Products and Dietary Supplements Are Not Interchangeable.

    PubMed

    Hilleman, Daniel; Smer, Aiman

    2016-01-01

    To provide an overview of prescription and dietary supplement omega-3 fatty acid (OM3-FA) products and considerations for clinical use. Narrative review. The PubMed database was searched for cardiovascular-related investigations focused on eicosapentaenoic acid (EPA) and/or docosahexaenoic acid (DHA) (limit: English-only articles). Additional regulatory information on prescription and dietary supplements was obtained from United States Food and Drug Administration online sources. Prescription QM3-FA products are supported by robust clinical development and safety monitoring programs, whereas dietary supplements are not required to demonstrate safety or efficacy prior to marketing. There are no over-the-counter OM3-FA products available in the United States. Investigations of OM3-FA dietary supplements show that quantities of EPA and DHA are highly variable within and between brands. Dietary supplements also may contain potentially harmful components, including oxidized OM3-FA, other lipids, cholesterol, and toxins. Prescription OM3-FA products may contain DHA and EPA or EPA alone. All prescription OM3-FA products have demonstrated statistically significant triglyceride reduction as monotherapy or in combination with statins in patients with hypertriglyceridemia. Differential effects between products containing EPA and DHA compared with a high-purity EPA product (icosapent ethyl) have clinical implications: Increases in low-density lipoprotein cholesterol associated with DHA have the potential to confound strategies for managing patients with dyslipidemia. Cardiovascular outcomes studies of prescription CM3-FA products are ongoing. OM3-FA dietary supplements should not be substituted for prescription products, and prescription OM3-FA products that contain DHA are not equivalent to or interchangeable with high-purity EPA (icosapent ethyl) and should not be substituted for it.

  15. Succinic acid production from cellobiose by Actinobacillus succinogenes.

    PubMed

    Jiang, Min; Xu, Rong; Xi, Yong-Lan; Zhang, Jiu-Hua; Dai, Wen-Yu; Wan, Yue-Jia; Chen, Ke-Quan; Wei, Ping

    2013-05-01

    In this study, cellobiose, a reducing disaccharide was used to produce succinic acid by Actinobacillus succinogenes NJ113. A final succinic acid concentration of 30.3g/l with a yield of 67.8% was achieved from an initial cellobiose concentration of 50 g/l via batch fermentation in anaerobic bottles. The cellobiose uptake mechanism was investigated and the results of enzyme assays revealed that the phosphoenolpyruvate phosphotransferase system (PEP-PTS) played an important role in the cellobiose uptake process. In batch fermentation with 18 g/l of cellobiose and 17 g/l of other sugars from sugarcane bagasse cellulose hydrolysates, a succinic acid concentration of 20.0 g/l was obtained, with a corresponding yield of 64.7%. This study found that cellobiose from incomplete hydrolysis of cellulose could be a potential carbon source for economical and efficient succinic acid production by A. succinogenes. Copyright © 2012 Elsevier Ltd. All rights reserved.

  16. Food-associated lactic acid bacteria with antimicrobial potential from traditional Mexican foods.

    PubMed

    Alvarado, C; García Almendárez, B E; Martin, S E; Regalado, C

    2006-01-01

    This work was conducted to identify indigenous LAB capable of antimicrobial activity, present in traditional Mexican-foods with potential as natural preservatives. A total of 27 artisan unlabeled Mexican products were evaluated, from which 94 LAB strains were isolated, and only 25 strains showed antimicrobial activity against at least one pathogen indicator microorganism. Most of the inhibitory activity showed by the isolated LAB strains was attributed to pH reduction by organic acids. Lactobacillus and Lactococcus strains were good acid producers, depending on the substrate, and may enhance the safety of food products. Cell free cultures of Leuconostoc mesenteroides CH210, and PT8 (from chorizo and pulque, respectively) reduced the number of viable cells of enteropathogenic E. coli in broth system. Lb. plantarum CC10 (from "madre" of vinegar) showed significant inhibitory effect against S. aureus 8943. E. faecium QPII (from panela cheese) produced a bacteriocin with wide anti-L. monocytogenes activity. Selected LAB from traditional Mexican foods showed good potential as bio-preservatives.

  17. Enterococcus faecium QU 50: a novel thermophilic lactic acid bacterium for high-yield l-lactic acid production from xylose.

    PubMed

    Abdel-Rahman, Mohamed Ali; Tashiro, Yukihiro; Zendo, Takeshi; Sakai, Kenji; Sonomoto, Kenji

    2015-01-01

    Production of optically pure lactic acid from lignocellulosic material for commercial purposes is hampered by several difficulties, including heterofermentation of pentose sugars and high energy consumption by mesophilic lactic acid bacteria. Here, we report a novel lactic acid bacterium, strain QU 50, that has the potential to produce optically pure l-lactic acid (≥99.2%) in a homofermentative manner from xylose under thermophilic conditions. Strain QU 50 was isolated from Egyptian fertile soil and identified as Enterococcus faecium QU 50 by analyzing its sugar fermentation pattern and 16S rRNA gene sequence. Enterococcus faecium QU 50 fermented xylose efficiently to produce lactic acid over wide pH (6.0-10.0) and temperature ranges (30-52°C), with a pH of 6.5 and temperature of 50°C being optimal. To our knowledge, this is the first report of homofermentative lactic acid production from xylose by a thermophilic lactic acid bacterium. © FEMS 2014. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  18. Potential SSP Perfluorooctanoic Acid Related Fluoropolymer Materials Obsolescence

    NASA Technical Reports Server (NTRS)

    Segars, Matt G.

    2006-01-01

    The Shuttle Environmental Assurance Initiative (SEA) has identified a potential for the Space Shuttle Program (SSP) to incur materials obsolescence issues due to agreements between the fluoro-chemical industry and the United States Environmental Protection Agency (USEPA) to participate in a Global Stewardship Program for perfluorooctanoic acid (PFOA). This presentation will include discussions of the chemistry, regulatory drivers, affected types of fluoropolymer and fluoroelastomer products, timeline for reformulations, and methodology for addressing the issue. It will cover the coordination of assessment efforts with the International Space Station and Head Quarters Air Force Space Command, along with some examples of impacted materials. The presentation is directed at all members of the international aerospace community concerned with identifying potential environmentally driven materials obsolescence issues.

  19. Homofermentative production of D-lactic acid from sucrose by a metabolically engineered Escherichia coli.

    PubMed

    Wang, Yongze; Tian, Tian; Zhao, Jinfang; Wang, Jinhua; Yan, Tao; Xu, Liyuan; Liu, Zao; Garza, Erin; Iverson, Andrew; Manow, Ryan; Finan, Chris; Zhou, Shengde

    2012-11-01

    Escherichia coli W, a sucrose-positive strain, was engineered for the homofermentative production of D-lactic acid through chromosomal deletion of the competing fermentative pathway genes (adhE, frdABCD, pta, pflB, aldA) and the repressor gene (cscR) of the sucrose operon, and metabolic evolution for improved anaerobic cell growth. The resulting strain, HBUT-D, efficiently fermented 100 g sucrose l(-1) into 85 g D-lactic acid l(-1) in 72-84 h in mineral salts medium with a volumetric productivity of ~1 g l(-1) h(-1), a product yield of 85 % and D-lactic acid optical purity of 98.3 %, and with a minor by-product of 4 g acetate l(-1). HBUT-D thus has great potential for production of D-lactic acid using an inexpensive substrate, such as sugar cane and/or beet molasses, which are primarily composed of sucrose.

  20. Efficient production of succinic acid from herbal extraction residue hydrolysate.

    PubMed

    Wang, Caixia; Su, Xinyao; Sun, Wei; Zhou, Sijing; Zheng, Junyu; Zhang, Mengting; Sun, Mengchu; Xue, Jianping; Liu, Xia; Xing, Jianmin; Chen, Shilin

    2018-06-15

    In this study, six different herbal-extraction residues were evaluated for succinic acid production in terms of chemical composition before and after dilute acid pretreatment (DAP) and sugar release performance. Chemical composition showed that pretreated residues of Glycyrrhiza uralensis Fisch (GUR) and Morus alba L. (MAR) had the highest cellulose content, 50% and 52%, respectively. Higher concentrations of free sugars (71.6 g/L total sugar) and higher hydrolysis yield (92%) were both obtained under 40 FPU/g DM at 10% solid loading for GUR. Using scanning electron microscopy (SEM), GUR was found to show a less compact structure due to process of extraction. Specifically, the fibers in pretreated GUR were coarse and disordered compared with that of GUR indicated by SEM. Finally, 65 g/L succinic acid was produced with a higher yield of 0.89 g/g total sugar or 0.49 g/g GUR. Our results illustrate the potential of GUR for succinic acid production. Copyright © 2018 Elsevier Ltd. All rights reserved.

  1. Thraustochytrids as production organisms for docosahexaenoic acid (DHA), squalene, and carotenoids.

    PubMed

    Aasen, Inga Marie; Ertesvåg, Helga; Heggeset, Tonje Marita Bjerkan; Liu, Bin; Brautaset, Trygve; Vadstein, Olav; Ellingsen, Trond E

    2016-05-01

    Thraustochytrids have been applied for industrial production of the omega-3 fatty acid docosahexaenoic (DHA) since the 1990s. During more than 20 years of research on this group of marine, heterotrophic microorganisms, considerable increases in DHA productivities have been obtained by process and medium optimization. Strains of thraustochytrids also produce high levels of squalene and carotenoids, two other commercially interesting compounds with a rapidly growing market potential, but where yet few studies on process optimization have been reported. Thraustochytrids use two pathways for fatty acid synthesis. The saturated fatty acids are produced by the standard fatty acid synthesis, while DHA is synthesized by a polyketide synthase. However, fundamental knowledge about the relationship between the two pathways is still lacking. In the present review, we extract main findings from the high number of reports on process optimization for DHA production and interpret these in the light of the current knowledge of DHA synthesis in thraustochytrids and lipid accumulation in oleaginous microorganisms in general. We also summarize published reports on squalene and carotenoid production and review the current status on strain improvement, which has been hampered by the yet very few published genome sequences and the lack of tools for gene transfer to the organisms. As more sequences now are becoming available, targets for strain improvement can be identified and open for a system-level metabolic engineering for improved productivities.

  2. Characterization of a Potential Probiotic Lactobacillus brevis RK03 and Efficient Production of γ-Aminobutyric Acid in Batch Fermentation.

    PubMed

    Wu, Chien-Hui; Hsueh, Yi-Huang; Kuo, Jen-Min; Liu, Si-Jia

    2018-01-04

    Lactic acid bacteria were isolated from fish and evaluated for their γ-aminobutyric acid (GABA)-producing abilities. Out of thirty-two isolates, Lactobacillus brevis RK03 showed the highest GABA production ability. The effects of various fermentation parameters including initial glutamic acid level, culture temperature, initial pH, and incubation time on GABA production were investigated via a singleparameter optimization strategy. For industrial large-scale production, a low-cost GABA producing medium (GM) broth was developed for fermentation with L. brevis RK03. We found that an optimized GM broth recipe of 1% glucose; 2.5% yeast extract; 2 ppm each of CaCO₃, MnSO₄, and Tween 80; and 10 μM pyridoxal phosphate (PLP) resulted in a maximum GABA yield of 62,523 mg/L after 88 h following the addition of 650 mM monosodium glutamate (MSG), for a conversion rate of 93.28%. Our data provide a practical approach for the highly efficient and economic production of GABA. In addition, L. brevis RK03 is highly resistant to gastric acid and bovine bile salt. Thus, the discovery of Lactobacillus strains with the ability to synthesize GABA may offer new opportunities in the design of improved health-promoting functional foods.

  3. Characterization of a Potential Probiotic Lactobacillus brevis RK03 and Efficient Production of γ-Aminobutyric Acid in Batch Fermentation

    PubMed Central

    Hsueh, Yi-Huang; Kuo, Jen-Min; Liu, Si-Jia

    2018-01-01

    Lactic acid bacteria were isolated from fish and evaluated for their γ-aminobutyric acid (GABA)-producing abilities. Out of thirty-two isolates, Lactobacillus brevis RK03 showed the highest GABA production ability. The effects of various fermentation parameters including initial glutamic acid level, culture temperature, initial pH, and incubation time on GABA production were investigated via a singleparameter optimization strategy. For industrial large-scale production, a low-cost GABA producing medium (GM) broth was developed for fermentation with L. brevis RK03. We found that an optimized GM broth recipe of 1% glucose; 2.5% yeast extract; 2 ppm each of CaCO3, MnSO4, and Tween 80; and 10 μM pyridoxal phosphate (PLP) resulted in a maximum GABA yield of 62,523 mg/L after 88 h following the addition of 650 mM monosodium glutamate (MSG), for a conversion rate of 93.28%. Our data provide a practical approach for the highly efficient and economic production of GABA. In addition, L. brevis RK03 is highly resistant to gastric acid and bovine bile salt. Thus, the discovery of Lactobacillus strains with the ability to synthesize GABA may offer new opportunities in the design of improved health-promoting functional foods. PMID:29300336

  4. Toward Sustainable Amino Acid Production.

    PubMed

    Usuda, Yoshihiro; Hara, Yoshihiko; Kojima, Hiroyuki

    Because the global amino acid production industry has been growing steadily and is expected to grow even more in the future, efficient production by fermentation is of great importance from economic and sustainability viewpoints. Many systems biology technologies, such as genome breeding, omics analysis, metabolic flux analysis, and metabolic simulation, have been employed for the improvement of amino acid-producing strains of bacteria. Synthetic biological approaches have recently been applied to strain development. It is also important to use sustainable carbon sources, such as glycerol or pyrolytic sugars from cellulosic biomass, instead of conventional carbon sources, such as glucose or sucrose, which can be used as food. Furthermore, reduction of sub-raw substrates has been shown to lead to reduction of environmental burdens and cost. Recently, a new fermentation system for glutamate production under acidic pH was developed to decrease the amount of one sub-raw material, ammonium, for maintenance of culture pH. At the same time, the utilization of fermentation coproducts, such as cells, ammonium sulfate, and fermentation broth, is a useful approach to decrease waste. In this chapter, further perspectives for future amino acid fermentation from one-carbon compounds are described.

  5. Citric Acid Production by Aspergillus niger Cultivated on Parkia biglobosa Fruit Pulp

    PubMed Central

    Abidoye, Khadijat Toyin; Tahir, Hauwa; Ibrahim, Aliyu Dabai; Aransiola, Sesan Abiodun

    2014-01-01

    The study was conducted to investigate the potential of Parkia biglobosa fruit pulp as substrate for citric acid production by Aspergillus niger. Reducing sugar was estimated by 3,5-dinitrosalicylic acid and citric acid was estimated spectrophotometrically using pyridine-acetic anhydride methods. The studies revealed that production parameters (pH, inoculum size, substrate concentration, incubation temperature, and fermentation period) had profound effect on the amount of citric acid produced. The maximum yield was obtained at the pH of 2 with citric acid of 1.15 g/L and reducing sugar content of 0.541 mMol−1, 3% vegetative inoculum size with citric acid yield of 0.53 g/L and reducing sugar content of 8.87 mMol−1, 2% of the substrate concentration with citric acid yield of 0.83 g/L and reducing sugar content of 9.36 mMol−1, incubation temperature of 55°C with citric acid yield of 0.62 g/L and reducing sugar content of 8.37 mMol−1, and fermentation period of 5 days with citric acid yield of 0.61 g/L and reducing sugar content of 3.70 mMol−1. The results of this study are encouraging and suggest that Parkia biglobosa pulp can be harnessed at low concentration for large scale citric acid production. PMID:27433535

  6. Production of γ-aminobutyric acid by microorganisms from different food sources.

    PubMed

    Hudec, Jozef; Kobida, Ľubomír; Čanigová, Margita; Lacko-Bartošová, Magdaléna; Ložek, Otto; Chlebo, Peter; Mrázová, Jana; Ducsay, Ladislav; Bystrická, Judita

    2015-04-01

    γ-Aminobutyric acid (GABA) is a potentially bioactive component of foods and pharmaceuticals. The aim of this study was screen lactic acid bacteria belonging to the Czech Collection of Microorganisms, and microorganisms (yeast and bacteria) from 10 different food sources for GABA production by fermentation in broth or plant and animal products. Under an aerobic atmosphere, very low selectivity of GABA production (from 0.8% to 1.3%) was obtained using yeast and filamentous fungi, while higher selectivity (from 6.5% to 21.0%) was obtained with bacteria. The use of anaerobic conditions, combined with the addition of coenzyme (pyridoxal-5-phosphate) and salts (CaCl2 , NaCl), led to the detection of a low concentration of GABA precursor. Simultaneously, using an optimal temperature of 33 °C, a pH of 6.5 and bacteria from banana (Pseudomonadaceae and Enterobacteriaceae families), surprisingly, a high selectivity of GABA was obtained. A positive impact of fenugreek sprouts on the proteolytic process and GABA production from plant material as a source of GABA precursor was identified. Lactic acid bacteria for the production of new plant and animal GABA-rich products from different natural sources containing GABA precursor can be used. © 2014 Society of Chemical Industry.

  7. Morphological regulation of Aspergillus niger to improve citric acid production by chsC gene silencing.

    PubMed

    Sun, Xiaowen; Wu, Hefang; Zhao, Genhai; Li, Zhemin; Wu, Xihua; Liu, Hui; Zheng, Zhiming

    2018-04-02

    The mycelial morphology of Aspergillus niger, a major filamentous fungus used for citric acid production, is important for citric acid synthesis during submerged fermentation. To investigate the involvement of the chitin synthase gene, chsC, in morphogenesis and citric acid production in A. niger, an RNAi system was constructed to silence chsC and the morphological mutants were screened after transformation. The compactness of the mycelial pellets was obviously reduced in the morphological mutants, with lower proportion of dispersed mycelia. These morphological changes have caused a decrease in viscosity and subsequent improvement in oxygen and mass transfer efficiency, which may be conducive for citric acid accumulation. All the transformants exhibited improvements in citric acid production; in particular, chsC-3 showed 42.6% higher production than the original strain in the shake flask. Moreover, the high-yield strain chsC-3 exhibited excellent citric acid production potential in the scale-up process.The citric acid yield and the conversion rate of glucose of chsC-3 were both improved by 3.6%, when compared with that of the original strain in the stirred tank bioreactor.

  8. Scale-up laccase production from Trametes versicolor stimulated by vanillic acid.

    PubMed

    Wang, Ke-Feng; Hu, Jian-Hua; Guo, Chen; Liu, Chun-Zhao

    2016-07-01

    An efficient strategy for laccase production in Trametes versicolor cultures was developed using vanillic acid as the inducer. The optimized vanillic acid treatment strategy consisted of exposing 2-day-old mycelia cultures to 80 mg/L vanillic acid. After 4 days, laccase activity of 588.84 U/L was achieved in flasks which represented a 1.79-fold increase compared to the control. In 200-L airlift bioreactor, the maximal laccase activity reached up to 785.12 U/L using the optimized vanillic acid treatment strategy. The zymograms of culture supernatants revealed three bands with laccase activity, among which Lac1 and Lac2 were abundant laccase isoforms constitutively expressed, and Lac3 was an inducible isozyme by vanillic acid. The results of real-time quantitative PCR showed that the transcription level of lcc in T. versicolor cultures grown with vanillic acid for 7 days was about 5.64-fold greater than that without vanillic acid in flasks. In 200-L airlift bioreactor cultures of T. versicolor with addition of vanillic acid, the transcript level of lcc at day 7 was 2.62-fold higher than that in flasks with vanillic acid due to the good mass transfer and oxygen supply in the bioreactor system. This study provides a basis for understanding the induction mechanism of vanillic acid for laccase production and has good potential for industrial applications.

  9. Chicoric acid: chemistry, distribution, and production

    NASA Astrophysics Data System (ADS)

    Lee, Jungmin; Scagel, Carolyn

    2013-12-01

    Though chicoric acid was first identified in 1958, it was largely ignored until recent popular media coverage cited potential health beneficial properties from consuming food and dietary supplements containing this compound. To date, plants from at least 63 genera and species have been found to contain chicoric acid, and while the compound is used as a processing quality indicator, it may also have useful health benefits. This review of chicoric acid summarizes research findings and highlights gaps in research knowledge for investigators, industry stakeholders, and consumers alike. Additionally, chicoric acid identification and quantification methods, biosynthesis, processing improvements to increase chicoric acid retention, and potential areas for future research are discussed.

  10. Chicoric acid: chemistry, distribution, and production.

    PubMed

    Lee, Jungmin; Scagel, Carolyn F

    2013-01-01

    Though chicoric acid was first identified in 1958, it was largely ignored until recent popular media coverage cited potential health beneficial properties from consuming food and dietary supplements containing this compound. To date, plants from at least 63 genera and species have been found to contain chicoric acid, and while the compound is used as a processing quality indicator, it may also have useful health benefits. This review of chicoric acid summarizes research findings and highlights gaps in research knowledge for investigators, industry stakeholders, and consumers alike. Additionally, chicoric acid identification, and quantification methods, biosynthesis, processing improvements to increase chicoric acid retention, and potential areas for future research are discussed.

  11. Degradation of tannic acid by cold-adapted Klebsiella sp NACASA1 and phytotoxicity assessment of tannic acid and its degradation products.

    PubMed

    Jadhav, Umesh; Kadu, Sudhir; Thokal, Nilesh; Padul, Manohar; Dawkar, Vishal; Chougale, Ashok; Salve, Abhay; Patil, Manoj

    2011-08-01

    The focus of the present study is to know the potential of bacterial isolate for tannic acid degradation at low temperature. Also, we tried to evaluate the suitability of phytotoxicity testing protocol for the determination of tannic acid toxicity. Screening for tannic acid degrading bacterial strains was carried out by using microbial isolation techniques. The 16S rDNA amplicon of the isolate was used to identify the isolate. The effect of different concentrations of tannic acid and its degradation products on germination of Vigna unguiculata was evaluated. The study was carried out to determine total sugar and starch content of the used seeds and even to check the presence of α-amylase activity during seed germination. The isolated bacterium was identified as Klebsiella sp NACASA1 and it showed degradation of tannic acid in 40 (±0.85***) h at 15°C and pH 7.0. A gradual decrease in root/shoot length was observed with increasing concentration of tannic acid. There was 95.11 (±0.24**)% inhibition in α-amylase activity at 20,000 ppm tannic acid, as compared to control. No such effects were observed on germination, root-shoot length, and α-amylase activity with tannic acid degradation products. The results obtained confirmed that tannic acid may act as a toxic agent in plant cells. The simple biodegradation process presented in this study was found to be effective in reducing toxicity of tannic acid. Also, it reveals the potential of soil bacterium to degrade tannic acid at low temperature.

  12. Enhancement of acidogenic fermentation for volatile fatty acid production from food waste: Effect of redox potential and inoculum.

    PubMed

    Yin, Jun; Yu, Xiaoqin; Zhang, Yeer; Shen, Dongsheng; Wang, Meizhen; Long, Yuyang; Chen, Ting

    2016-09-01

    The aim of this study was to explore the effects of redox potential (ORP) and inoculum on volatile fatty acids (VFAs) production from food waste by acidogenic fermentation. Four experimental conditions with two ORP levels were tested: limited aeration conditions with ORP level of -100 to -200mV inoculating anaerobic sludge (LA+AnS) or aerobic sludge (LA+AeS), and anaerobic conditions with ORP level of -200 to -300mV inoculating anaerobic sludge with 2-bromoethanosulfophate (AN+BES) and without BES (AN). The maximal VFA yield (0.79g COD/g VS) was attained in LA+AnS reactor due to enhanced hydrolysis of substrates, especially proteins (degradation efficiency 78.3%). A higher frequency of phylum Firmicutes under limited aeration conditions (42.2-48.2%) was observed than that under anaerobic conditions (21.1%). The microbial community was more diverse in LA+AnS reactors than LA+AeS. We conclude that appropriate ORP level (from -100 to -200mV) and inoculum play essential roles in VFA production. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. Succinic acid production from sucrose by Actinobacillus succinogenes NJ113.

    PubMed

    Jiang, Min; Dai, Wenyu; Xi, Yonglan; Wu, Mingke; Kong, Xiangping; Ma, Jiangfeng; Zhang, Min; Chen, Kequan; Wei, Ping

    2014-02-01

    In this study, sucrose, a reproducible disaccharide extracted from plants, was used as the carbon source for the production of succinic acid by Actinobacillus succinogenes NJ113. During serum bottle fermentation, the succinic acid concentration reached 57.1g/L with a yield of 71.5%. Further analysis of the sucrose utilization pathways revealed that sucrose was transported and utilized via a sucrose phosphotransferase system, sucrose-6-phosphate hydrolase, and a fructose PTS. Compared to glucose utilization in single pathway, more pathways of A. succinogenes NJ113 are dependent on sucrose utilization. By changing the control strategy in a fed-batch culture to alleviate sucrose inhibition, 60.5g/L of succinic acid was accumulated with a yield of 82.9%, and the productivity increased by 35.2%, reaching 2.16g/L/h. Thus utilization of sucrose has considerable potential economics and environmental meaning. Copyright © 2014 Elsevier Ltd. All rights reserved.

  14. Optimization of D-lactic acid production using unutilized biomass as substrates by multiple parallel fermentation.

    PubMed

    Mufidah, Elya; Wakayama, Mamoru

    2016-12-01

    This study investigated the optimization of D-lactic acid production from unutilized biomass, specifically banana peel and corncob by multiple parallel fermentation (MPF) with Leuconostoc mesenteroides and Aspergillus awamori. The factors involved in MPF that were assessed in this study comprised banana peel and corncob, KH 2 PO 4 , Tween 80, MgSO 4 ·7H 2 O, NaCl, yeast extract, and diammonium hydrogen citrate to identify the optimal concentration for D-lactic acid production. Optimization of these component factors was performed using the Taguchi method with an L8 orthogonal array. The optimal concentrations for the effectiveness of MPF using biomass substrates were as follows: (1) banana peel, D-lactic acid production was 31.8 g/L in medium containing 15 % carbon source, 0.5 % KH 2 PO 4 , 0.1 % Tween 80, 0.05 % MgSO 4 ·7H 2 O, 0.05 % NaCl, 1.5 % yeast extract, and 0.2 % diammonium hydrogen citrate. (2) corncob, D-lactic acid production was 38.3 g/L in medium containing 15 % of a carbon source, 0.5 % KH 2 PO 4 , 0.1 % Tween 80, 0.05 % MgSO 4 ·7H 2 O, 0.1 % NaCl, 1.0 % yeast extract, and 0.4 % diammonium hydrogen citrate. Thus, both banana peel and corncob are unutilized potential resources for D-lactic acid production. These results indicate that MPF using L. mesenteroides and A. awamori could constitute part of a potential industrial application of the currently unutilized banana peel and corncob biomass for D-lactic acid production.

  15. Fatty acid composition of Swedish bakery products, with emphasis on trans-fatty acids.

    PubMed

    Trattner, Sofia; Becker, Wulf; Wretling, Sören; Öhrvik, Veronica; Mattisson, Irene

    2015-05-15

    Trans-fatty acids (TFA) have been associated with increased risk of coronary heart disease, by affecting blood lipids and inflammation factors. Current nutrition recommendations emphasise a limitation of dietary TFA intake. The aim of this study was to investigate fatty acid composition in sweet bakery products, with emphasis on TFA, on the Swedish market and compare fatty acid composition over time. Products were sampled in 2001, 2006 and 2007 and analysed for fatty acid composition by using GC. Mean TFA levels were 0.7% in 2007 and 5.9% in 2001 of total fatty acids. In 1995-97, mean TFA level was 14.3%. In 2007, 3 of 41 products had TFA levels above 2% of total fatty acids. TFA content had decreased in this product category, while the proportion of saturated (SFA) and polyunsaturated (PUFA) fatty acids had increased, mostly through increased levels of 16:0 and 18:2 n-6, respectively. The total fat content remained largely unchanged. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

  16. Chicoric acid: chemistry, distribution, and production

    PubMed Central

    Lee, Jungmin; Scagel, Carolyn F.

    2013-01-01

    Though chicoric acid was first identified in 1958, it was largely ignored until recent popular media coverage cited potential health beneficial properties from consuming food and dietary supplements containing this compound. To date, plants from at least 63 genera and species have been found to contain chicoric acid, and while the compound is used as a processing quality indicator, it may also have useful health benefits. This review of chicoric acid summarizes research findings and highlights gaps in research knowledge for investigators, industry stakeholders, and consumers alike. Additionally, chicoric acid identification, and quantification methods, biosynthesis, processing improvements to increase chicoric acid retention, and potential areas for future research are discussed. PMID:24790967

  17. Microbial production of lactic acid: the latest development.

    PubMed

    Juturu, Veeresh; Wu, Jin Chuan

    2016-12-01

    Lactic acid is an important platform chemical for producing polylactic acid (PLA) and other value-added products. It is naturally produced by a wide spectrum of microbes including bacteria, yeast and filamentous fungi. In general, bacteria ferment C5 and C6 sugars to lactic acid by either homo- or hetero-fermentative mode. Xylose isomerase, phosphoketolase, transaldolase, l- and d-lactate dehydrogenases are the key enzymes that affect the ways of lactic acid production. Metabolic engineering of microbial strains are usually needed to produce lactic acid from unconventional carbon sources. Production of d-LA has attracted much attention due to the demand for producing thermostable PLA, but large scale production of d-LA has not yet been commercialized. Thermophilic Bacillus coagulans strains are able to produce l-lactic acid from lignocellulose sugars homo-fermentatively under non-sterilized conditions, but the lack of genetic tools for metabolically engineering them severely affects their development for industrial applications. Pre-treatment of agriculture biomass to obtain fermentable sugars is a pre-requisite for utilization of the huge amounts of agricultural biomass to produce lactic acid. The major challenge is to obtain quality sugars of high concentrations in a cost effective-way. To avoid or minimize the use of neutralizing agents during fermentation, genetically engineering the strains to make them resist acidic environment and produce lactic acid at low pH would be very helpful for reducing the production cost of lactic acid.

  18. Net endogenous acid production is associated with a faster decline in GFR in African Americans

    PubMed Central

    Scialla, Julia J.; Appel, Lawrence J.; Astor, Brad C.; Miller, Edgar R.; Beddhu, Srinivasan; Woodward, Mark; Parekh, Rulan S.; Anderson, Cheryl A. M.

    2012-01-01

    Increased acid excretion may promote renal injury. To evaluate this in African Americans with hypertensive nephrosclerosis, we studied the association between the net endogenous acid production and progression of kidney disease in 632 patients in the AASK trial. Protein and potassium intakes were estimated from 24-hour urea nitrogen and potassium excretion, and used to estimate net endogenous acid production, averaged over 2 years, approximating routine intake. The link between net endogenous acid production and the I125iothalamate glomerular filtration rate (iGFR) and time to end stage renal disease or doubling of serum creatinine was analyzed using mixed models and Cox proportional hazards regressions. The trend in higher net endogenous acid production was significantly associated with a faster decline in iGFR over a median of 3.2 years. After adjustment for age, body mass index, baseline iGFR, urine protein to creatinine ratio and randomized treatment group, the trend in higher net endogenous acid production remained significantly associated with a faster decline in iGFR at a rate 1.01 mL/min/1.73 m2 per year faster in the highest to the lowest quartile. However, in time to event analyses over a median of 7.7 years, the adjusted hazard ratio (1.10) for composite renal events per 25 mEq/day higher net endogenous acid production was not significant. Hence, our findings implicate endogenous acid production as a potential modifiable risk factor for progressive kidney disease. PMID:22475819

  19. The Potential of Microalgae Lipids for Edible Oil Production.

    PubMed

    Huang, Yanfei; Zhang, Dongmei; Xue, Shengzhang; Wang, Meng; Cong, Wei

    2016-10-01

    The objective of this study was to evaluate the potential of oil-rich green algae, Chlorella vulgaris, Scenedesmus obliquus, and Nannochloropsis oceanica, to produce edible oil with respect to lipid and residue properties. The results showed that C. vulgaris and N. oceanica had similarly much higher lipid recovery (about 50 %) in hexane extraction than that of S. obliquus (about 25 %), and C. vulgaris had the highest content of neutral lipids among the three algae. The fatty acid compositions of neutral lipids from C. vulgaris and S. obliquus were mainly C16 and C18, resembling that of vegetable oils. ARA and EPA were the specific valuable fatty acids in lipids of N. oceanica, but the content of which was lower in neutral lipids. Phytol was identified as the major unsaponifiable component in lipids of the three algae. Combined with the evaluation of the ratios in SFA/MUFA/PUFA, (n-6):(n-3) and content of free fatty acids, lipids obtained from C. vulgaris displayed the great potential for edible oil production. Lipids of N. oceanica showed the highest antioxidant activity, and its residue contained the largest amounts of protein as well as the amino acid compositions were greatly beneficial to the health of human beings.

  20. The Efficient Clade: Lactic Acid Bacteria for Industrial Chemical Production.

    PubMed

    Sauer, Michael; Russmayer, Hannes; Grabherr, Reingard; Peterbauer, Clemens K; Marx, Hans

    2017-08-01

    Lactic acid bacteria are well known to be beneficial for food production and, as probiotics, they are relevant for many aspects of health. However, their potential as cell factories for the chemical industry is only emerging. Many physiological traits of these microorganisms, evolved for optimal growth in their niche, are also valuable in an industrial context. Here, we illuminate these features and describe why the distinctive adaptation of lactic acid bacteria is particularly useful when developing a microbial process for chemical production from renewable resources. High carbon uptake rates with low biomass formation combined with strictly regulated simple metabolic pathways, leading to a limited number of metabolites, are among the key factors defining their success in both nature and industry. Copyright © 2017 Elsevier Ltd. All rights reserved.

  1. Lactic acid and methane: improved exploitation of biowaste potential.

    PubMed

    Dreschke, G; Probst, M; Walter, A; Pümpel, T; Walde, J; Insam, H

    2015-01-01

    This feasibility study investigated a two-step biorefining approach to increase the value gained by recycling of organic municipal solid waste. Firstly, lactic acid was produced via batch fermentation at 37°C using the indigenous microbiome. Experiments revealed an optimal fermentation period of 24h resulting in high yields of lactic acid (up to 37gkg(-1)). The lactic acid proportion of total volatile fatty acid content reached up to 83%. Lactobacilli were selectively enriched to up to 75% of the bacterial community. Additionally conversion of organic matter to lactic acid was increased from 22% to 30% through counteracting end product inhibition by continuous lactic acid extraction. Secondly, fermentation residues were used as co-substrate in biomethane production yielding up to 618±41Nmlbiomethaneg(-1) volatile solids. Digestate, the only end product of this process can be used as organic fertilizer. Copyright © 2014 Elsevier Ltd. All rights reserved.

  2. d-lactic acid production from renewable lignocellulosic biomass via genetically modified Lactobacillus plantarum.

    PubMed

    Zhang, Yixing; Kumar, Amit; Hardwidge, Philip R; Tanaka, Tsutomu; Kondo, Akihiko; Vadlani, Praveen V

    2016-03-01

    d-lactic acid is of great interest because of increasing demand for biobased poly-lactic acid (PLA). Blending poly-l-lactic acid with poly-d-lactic acid greatly improves PLA's mechanical and physical properties. Corn stover and sorghum stalks treated with 1% sodium hydroxide were investigated as possible substrates for d-lactic acid production by both sequential saccharification and fermentation and simultaneous saccharification and cofermentation (SSCF). A commercial cellulase (Cellic CTec2) was used for hydrolysis of lignocellulosic biomass and an l-lactate-deficient mutant strain Lactobacillus plantarum NCIMB 8826 ldhL1 and its derivative harboring a xylose assimilation plasmid (ΔldhL1-pCU-PxylAB) were used for fermentation. The SSCF process demonstrated the advantage of avoiding feedback inhibition of released sugars from lignocellulosic biomass, thus significantly improving d-lactic acid yield and productivity. d-lactic acid (27.3 g L(-1) ) and productivity (0.75 g L(-1) h(-1) ) was obtained from corn stover and d-lactic acid (22.0 g L(-1) ) and productivity (0.65 g L(-1) h(-1) ) was obtained from sorghum stalks using ΔldhL1-pCU-PxylAB via the SSCF process. The recombinant strain produced a higher concentration of d-lactic acid than the mutant strain by using the xylose present in lignocellulosic biomass. Our findings demonstrate the potential of using renewable lignocellulosic biomass as an alternative to conventional feedstocks with metabolically engineered lactic acid bacteria to produce d-lactic acid. © 2016 American Institute of Chemical Engineers Biotechnol. Prog., 32:271-278, 2016. © 2016 American Institute of Chemical Engineers.

  3. Detoxification of Sap from Felled Oil Palm Trunks for the Efficient Production of Lactic Acid.

    PubMed

    Kunasundari, Balakrishnan; Arai, Takamitsu; Sudesh, Kumar; Hashim, Rokiah; Sulaiman, Othman; Stalin, Natra Joseph; Kosugi, Akihiko

    2017-09-01

    The availability of fermentable sugars in high concentrations in the sap of felled oil palm trunks and the thermophilic nature of the recently isolated Bacillus coagulans strain 191 were exploited for lactic acid production under non-sterile conditions. Screening indicated that strain 191 was active toward most sugars including sucrose, which is a major component of sap. Strain 191 catalyzed a moderate conversion of sap sugars to lactic acid (53%) with a productivity of 1.56 g/L/h. Pretreatment of oil palm sap (OPS) using alkaline precipitation improved the sugar fermentability, providing a lactic acid yield of 92% and productivity of 2.64 g/L/h. To better characterize potential inhibitors in the sap, phenolic, organic, and mineral compounds were analyzed using non-treated sap and saps treated with activated charcoal and alkaline precipitation. Phthalic acid, 3,4-dimethoxybenzoic acid, aconitic acid, syringic acid, and ferulic acid were reduced in the sap after treatment. High concentrations of Mg, P, K, and Ca were also precipitated by the alkaline treatment. These results suggest that elimination of excess phenolic and mineral compounds in OPS can improve the fermentation yield. OPS, a non-food resource that is readily available in bulk quantities from plantation sites, is a promising source for lactic acid production.

  4. Potential use of fatty acid profiles of the adductor muscle of cockles (Cerastoderma edule) for traceability of collection site

    PubMed Central

    Ricardo, Fernando; Pimentel, Tânia; Moreira, Ana S. P.; Rey, Felisa; Coimbra, Manuel A.; Rosário Domingues, M.; Domingues, Pedro; Costa Leal, Miguel; Calado, Ricardo

    2015-01-01

    Geographic traceability of seafood is key for controlling its quality and safeguarding consumers’ interest. The present study assessed if the fatty acid (FA) profile of the adductor muscle (AM) of fresh cockles (Cerastoderma edule) can be used to discriminate the origin of specimens collected in different bivalve capture/production areas legally defined within a coastal lagoon. Results suggest that this biochemical approach holds the potential to trace sampling locations with a spatial resolution <10 Km, even for areas with identical classification for bivalve production. Cockles further away from the inlet, i.e. in areas exposed to a higher saline variation, exhibited lower levels of saturated fatty acids, which are key for stabilizing the bilayer structure of cell membranes, and a higher percentage of polyunsaturated fatty acids, which enhance bilayer fluidity. Results suggest that the structural nature of the lipids present in the AM provides a stable fatty acid signature and holds potential for tracing the origin of bivalves to their capture/production areas. PMID:26084395

  5. Guaiacol production from ferulic acid, vanillin and vanillic acid by Alicyclobacillus acidoterrestris.

    PubMed

    Witthuhn, R Corli; van der Merwe, Enette; Venter, Pierre; Cameron, Michelle

    2012-06-15

    Alicyclobacilli are thermophilic, acidophilic bacteria (TAB) that spoil fruit juice products by producing guaiacol. It is currently believed that guaiacol is formed by Alicyclobacillus in fruit juices as a product of ferulic acid metabolism. The aim of this study was to identify the precursors that can be metabolised by Alicyclobacillus acidoterrestris to produce guaiacol and to evaluate the pathway of guaiacol production. A. acidoterrestris FB2 was incubated at 45°C for 7days in Bacillus acidoterrestris (BAT) broth supplemented with ferulic acid, vanillin or vanillic acid, respectively. The samples were analysed every day to determine the cell concentration, the supplement concentration using high performance liquid chromatography with UV-diode array detection (HPLC-DAD) and the guaiacol concentration, using both the peroxidase enzyme colourimetric assay (PECA) and HPLC-DAD. The cell concentration of A. acidoterrestris FB2 during the 7days in all samples were above the critical cell concentration of 10(5)cfu/mL reportedly required for guaiacol production. The guaiacol produced by A. acidoterrestris FB2 increased with an increase in vanillin or vanillic acid concentration and a metabolic pathway of A. acidoterrestris FB2 directly from vanillin to guaiacol was established. The high concentration of vanillic acid (1000mg/L) resulted in an initial inhibitory effect on the cells, but the cell concentration increased after day 2. Guaiacol production did not occur in the absence of either a precursor or A. acidoterrestris FB2 and guaiacol was not produced by A. acidoterrestris FB2 in the samples supplemented with ferulic acid. The presence of Alicyclobacillus spp. that has the ability to produce guaiacol, as well as the substrates vanillin or vanillic acid is prerequisite for production of guaiacol. Copyright © 2012 Elsevier B.V. All rights reserved.

  6. Efficient production of triacylglycerols rich in docosahexaenoic acid (DHA) by osmo-heterotrophic marine protists.

    PubMed

    Liu, Ying; Tang, Jie; Li, Jingjing; Daroch, Maurycy; Cheng, Jay J

    2014-12-01

    Thraustochytrids have recently emerged as a promising source for docosahexaenoic acid (DHA) production due to their high growth rate and oil content. In this study, two thraustochytrid isolates, Aurantiochytrium sp. PKU#SW7 and Thraustochytriidae sp. PKU#Mn16 were used for DHA production. Following growth parameters were optimized to maximize DHA production: temperature, pH, salinity, and glucose concentration. Both isolates achieved the highest DHA yield at the cultivation temperature of 28 °C, pH 6, 100 % seawater, and 2 % glucose. A DHA yield of 1.395 g/l and 1.426 g/l was achieved under the optimized culture conditions. Further investigation revealed that both isolates possess simple fatty acids profiles with palmitic acid and DHA as their dominant constituents, accounting for ∼79 % of total fatty acids. To date, very few studies have focused on the DHA distribution in various lipid fractions which is an important factor for identifying strains with a potential for industrial DHA production. In the present study, the lipids profiles of each strain both revealed that the majority of DHA was distributed in neutral lipids (NLs), and the DHA distribution in NLs of PKU#SW7 was exclusively in the form of triacylglycerols (TAGs) which suggest that PKU#SW7 could be utilized as an alternative source of DHA for dietary supplements. The fermentation process established for both strains also indicating that Aurantiochytrium sp. PKU#SW7 was more suitable for cultivation in fermenter. In addition, the high percentage of saturated fatty acids produced by the two thraustochytrids indicates their potential application in biodiesel production. Overall, our findings suggest that two thraustochytrid isolates are suitable candidates for biotechnological applications.

  7. Omega-3 Fatty Acid Formulations in Cardiovascular Disease: Dietary Supplements are Not Substitutes for Prescription Products.

    PubMed

    Fialkow, Jonathan

    2016-08-01

    Omega-3 fatty acid products are available as prescription formulations (icosapent ethyl, omega-3-acid ethyl esters, omega-3-acid ethyl esters A, omega-3-carboxylic acids) and dietary supplements (predominantly fish oils). Most dietary supplements and all but one prescription formulation contain mixtures of the omega-3 fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). Products containing both EPA and DHA may raise low-density lipoprotein cholesterol (LDL-C). In clinical trials, the EPA-only prescription product, icosapent ethyl, did not raise LDL-C compared with placebo. To correct a common misconception, it is important to note that omega-3 fatty acid dietary supplements are not US FDA-approved over-the-counter drugs and are not required to demonstrate safety and efficacy prior to marketing. Conversely, prescription products are supported by extensive clinical safety and efficacy investigations required for FDA approval and have active and ongoing safety monitoring programs. While omega-3 fatty acid dietary supplements may have a place in the supplementation of diet, they generally contain lower levels of EPA and DHA than prescription products and are not approved or intended to treat disease. Perhaps due to the lack of regulation of dietary supplements, EPA and DHA levels may vary widely within and between brands, and products may also contain unwanted cholesterol or fats or potentially harmful components, including toxins and oxidized fatty acids. Accordingly, omega-3 fatty acid dietary supplements should not be substituted for prescription products. Similarly, prescription products containing DHA and EPA should not be substituted for the EPA-only prescription product, as DHA may raise LDL-C and thereby complicate the management of patients with dyslipidemia.

  8. Application of acid whey and set milk to marinate beef with reference to quality parameters and product safety.

    PubMed

    Wójciak, Karolina M; Krajmas, Paweł; Solska, Elżbieta; Dolatowski, Zbigniew J

    2015-01-01

    The aim of the study was to evaluate the potential of acid whey and set milk as a marinade in the traditional production of fermented eye round. Studies involved assaying pH value, water activity (aw), oxidation-reduction potential and TBARS value, colour parameters in CIE system (L*, a*, b*), assaying the number of lactic acid bacteria and certain pathogenic bacteria after ripening process and after 60-day storing in cold storage. Sensory analysis and analysis of the fatty acids profile were performed after completion of the ripening process. Analysis of pH value in the products revealed that application of acid whey to marinate beef resulted in increased acidity of ripening eye round (5.14). The highest value of the colour parameter a* after ripening process and during storage was observed in sample AW (12.76 and 10.07 respectively), the lowest on the other hand was observed in sample SM (10.06 and 7.88 respectively). The content of polyunsaturated fatty acids (PUFA) was higher in eye round marinated in acid whey by approx. 4% in comparison to other samples. Application of acid whey to marinade beef resulted in increased share of red colour in general colour tone as well as increased oxidative stability of the product during storage. It also increased the content of polyunsaturated fatty acids (PUFA) in the product. All model products had high content of lactic acid bacteria and there were no pathogenic bacteria such as: L. monocytogenes, Y. enterocolitica, S. aureus, Clostridium sp.

  9. Ascorbic acid reduces noise-induced nitric oxide production in the guinea pig ear.

    PubMed

    Heinrich, Ulf-Rüdiger; Fischer, Ilka; Brieger, Jürgen; Rümelin, Andreas; Schmidtmann, Irene; Li, Huige; Mann, Wolf J; Helling, Kai

    2008-05-01

    Noise-induced hearing loss can be caused, among other causes, by increased nitric oxide (NO) production in the inner ear leading to nitroactive stress and cell destruction. Some studies in the literature suggest that the degree of hearing loss (HL) could be reduced in an animal model through ascorbic acid supplementation. To identify the effect of ascorbic acid on tissue-dependent NO content in the inner ear of the guinea pig, we determined the local NO production in the organ of Corti and the lateral wall separately 6 hours after noise exposure. Prospective animal study in guinea pigs. Over a period of 7 days, male guinea pigs were supplied with minimum (25 mg/kg body weight/day) and maximum (525 mg/kg body weight/day) ascorbic acid doses, and afterwards exposed to noise (90 dB sound pressure level for 1 hour). The acoustic-evoked potentials were recorded before and after noise exposure. The organ of Corti and the lateral wall were incubated differently for 6 hours in culture medium, and the degree of NO production was determined by chemiluminescence. Ascorbic acid treatment reduced the hearing threshold shift after noise exposure depending on concentration. When the maximum ascorbic acid dose was substituted, NO production was significantly reduced in the lateral wall after noise exposure and slightly reduced in the organ of Corti. Oral supplementation of the natural radical scavenger ascorbic acid reduces the NO-production rate in the inner ear in noisy conditions. This finding supports the concept of inner ear protection by ascorbic acid supplementation.

  10. Fermentation and purification strategies for the production of betulinic acid and its lupane-type precursors in Saccharomyces cerevisiae.

    PubMed

    Czarnotta, Eik; Dianat, Mariam; Korf, Marcel; Granica, Fabian; Merz, Juliane; Maury, Jérôme; Baallal Jacobsen, Simo A; Förster, Jochen; Ebert, Birgitta E; Blank, Lars M

    2017-11-01

    Microbial production of plant derived, biologically active compounds has the potential to provide economic and ecologic alternatives to existing low productive, plant-based processes. Current production of the pharmacologically active cyclic triterpenoid betulinic acid is realized by extraction from the bark of plane tree or birch. Here, we reengineered the reported betulinic acid pathway into Saccharomyces cerevisiae and used this novel strain to develop efficient fermentation and product purification methods. Fed-batch cultivations with ethanol excess, using either an ethanol-pulse feed or controlling a constant ethanol concentration in the fermentation medium, significantly enhanced production of betulinic acid and its triterpenoid precursors. The beneficial effect of excess ethanol was further exploited in nitrogen-limited resting cell fermentations, yielding betulinic acid concentrations of 182 mg/L, and total triterpenoid concentrations of 854 mg/L, the highest concentrations reported so far. Purification of lupane-type triterpenoids with high selectivity and yield was achieved by solid-liquid extraction without prior cell disruption using polar aprotic solvents such as acetone or ethyl acetate and subsequent precipitation with strong acids. This study highlights the potential of microbial production of plant derived triterpenoids in S. cerevisiae by combining metabolic and process engineering. © 2017 Wiley Periodicals, Inc.

  11. Cyclic voltammetry to evaluate the antioxidant potential in winemaking by-products.

    PubMed

    José Jara-Palacios, M; Luisa Escudero-Gilete, M; Miguel Hernández-Hierro, J; Heredia, Francisco J; Hernanz, Dolores

    2017-04-01

    Grape pomace is composed of seeds, skins and stems that are an important source of phenolic substances, which have antioxidant properties and potential benefits to human health. Cyclic voltammetry (CV) has been used to measure the total antioxidant potential of different winemaking by-products. The electrochemical behavior of pomace, seeds, skins and stems was measured by CV and lipid peroxidation inhibition by thiobarbituric acid reactive substances (TBARS) method. Differences for the electrochemical parameter were found between the by-products, pomace and seeds, which presented the greatest voltammetric peak area. Furthermore, the by-products induced inhibition of lipid peroxidation in rat liver homogenates. Pomace and seeds showed higher capacity to inhibit lipid peroxidation than stems and skins, which could be because these by-products are richer in flavanols. Simple regression analyses showed that voltammetric parameters are highly correlated to the values obtained for lipid peroxidation inhibition. CV is a promising technique to estimate the total antioxidant potential of phenolic extract from winemaking by-products. Copyright © 2016 Elsevier B.V. All rights reserved.

  12. Potentiation of substance p by lysergic acid diethylamide in vivo

    PubMed Central

    Krivoy, W. A.

    1961-01-01

    In doses of 10 μg/kg or more, lysergic acid diethylamide enhanced the fourth potential (DR IV) of the dorsal root potential complex in the cat. Smaller doses of lysergic acid diethylamide did not in themselves alter the DR IV, but revealed an enhancement of the potential by substance P, which by itself had no effect. 2-Bromolysergic acid diethylamide had no action on the dorsal root potentials, but prevented the actions of lysergic acid diethylamide. PMID:13754427

  13. Marine Microbial-Derived Molecules and Their Potential Use in Cosmeceutical and Cosmetic Products

    PubMed Central

    Corinaldesi, Cinzia; Barone, Giulio; Marcellini, Francesca; Dell’Anno, Antonio; Danovaro, Roberto

    2017-01-01

    The oceans encompass a wide range of habitats and environmental conditions, which host a huge microbial biodiversity. The unique characteristics of several marine systems have driven a variety of biological adaptations, leading to the production of a large spectrum of bioactive molecules. Fungi, fungi-like protists (such as thraustochytrids) and bacteria are among the marine organisms with the highest potential of producing bioactive compounds, which can be exploited for several commercial purposes, including cosmetic and cosmeceutical ones. Mycosporines and mycosporine-like amino acids, carotenoids, exopolysaccharides, fatty acids, chitosan and other compounds from these microorganisms might represent a sustainable, low-cost and fast-production alternative to other natural molecules used in photo-protective, anti-aging and skin-whitening products for face, body and hair care. Here, we review the existing knowledge of these compounds produced by marine microorganisms, highlighting the marine habitats where such compounds are preferentially produced and their potential application in cosmetic and cosmeceutical fields. PMID:28417932

  14. Marine Microbial-Derived Molecules and Their Potential Use in Cosmeceutical and Cosmetic Products.

    PubMed

    Corinaldesi, Cinzia; Barone, Giulio; Marcellini, Francesca; Dell'Anno, Antonio; Danovaro, Roberto

    2017-04-12

    The oceans encompass a wide range of habitats and environmental conditions, which host a huge microbial biodiversity. The unique characteristics of several marine systems have driven a variety of biological adaptations, leading to the production of a large spectrum of bioactive molecules. Fungi, fungi-like protists (such as thraustochytrids) and bacteria are among the marine organisms with the highest potential of producing bioactive compounds, which can be exploited for several commercial purposes, including cosmetic and cosmeceutical ones. Mycosporines and mycosporine-like amino acids, carotenoids, exopolysaccharides, fatty acids, chitosan and other compounds from these microorganisms might represent a sustainable, low-cost and fast-production alternative to other natural molecules used in photo-protective, anti-aging and skin-whitening products for face, body and hair care. Here, we review the existing knowledge of these compounds produced by marine microorganisms, highlighting the marine habitats where such compounds are preferentially produced and their potential application in cosmetic and cosmeceutical fields.

  15. Biotechnological production of enantiomerically pure d-lactic acid.

    PubMed

    Klotz, Silvia; Kaufmann, Norman; Kuenz, Anja; Prüße, Ulf

    2016-11-01

    The fermentation process of l-lactic acid is well known. Little importance was attached to d-lactic acid, but in the past 10 years, d-lactic acid gained significantly in importance. d-Lactic acid is an interesting precursor for manufacturing heat-resistant polylactic acid (PLA) bioplastics which can be widely used, for example as packaging material, coatings, for textiles or in the automotive industry.This review provides a comprehensive overview of the most recent developments, including a spectrum of studied microorganisms and their capabilities for the production of d-lactic acid. Additionally, the technological achievements in biotechnological d-lactic acid production including fermentation techniques like fed batch, simultaneous saccharification, and fermentation and continuous techniques are presented. Attention is also turned to suitable alternative substrates and their applicability in fermentation processes. Furthermore, advantages and disadvantages of product recovery and purification are discussed. Economic aspects of PLA are pointed out, and the present industrial producers of lactic acid are briefly introduced.

  16. Efficient enzymatic production of hydroxy fatty acids by linoleic acid Δ9 hydratase from Lactobacillus plantarum AKU 1009a.

    PubMed

    Takeuchi, M; Kishino, S; Park, S-B; Hirata, A; Kitamura, N; Saika, A; Ogawa, J

    2016-05-01

    This study aims to produce hydroxy fatty acids efficiently. Escherichia coli overexpressing linoleic acid Δ9 hydratase from Lactobacillus plantarum AKU 1009a was employed to produce hydroxy fatty acids with industrial potential. We found that 280 g l(-1) of linoleic acid (1 mol l(-1)) was converted into (S)-10-hydoxy-cis-12-octadecenoic acid (HYA) with a high conversion rate of 98% (mol/mol) and more than 99·9% enantiomeric excess (e.e.) by recombinant E. coli cells in the presence of FAD and NADH. In the same way, many kinds of C18 unsaturated fatty acids with Δ9 carbon double bond (280 g l(-1)) were converted into corresponding 10-hydroxy fatty acids with the conversion rates over 95% (mol/mol). We also produced HYA at a high rate of accumulation (289 g l(-1) ) with a high yield (97 mol%) in a reaction mixture that contained glucose instead of NADH. We developed a process for producing several types of hydroxy fatty acids with high accumulation rates and high yields. Hydroxy fatty acids are important materials for the chemical, food, cosmetic and pharmaceutical industries, and thus they have recently attracted much interest in a variety of research fields. However, the mass production of hydroxy fatty acids has been limited. This method of hydroxy fatty acids production will facilitate the widespread application of hydroxy fatty acids in various industries. © 2016 The Society for Applied Microbiology.

  17. Caffeic acid production by simultaneous saccharification and fermentation of kraft pulp using recombinant Escherichia coli.

    PubMed

    Kawaguchi, Hideo; Katsuyama, Yohei; Danyao, Du; Kahar, Prihardi; Nakamura-Tsuruta, Sachiko; Teramura, Hiroshi; Wakai, Keiko; Yoshihara, Kumiko; Minami, Hiromichi; Ogino, Chiaki; Ohnishi, Yasuo; Kondo, Ahikiko

    2017-07-01

    Caffeic acid (3,4-dihydroxycinnamic acid) serves as a building block for thermoplastics and a precursor for biologically active compounds and was recently produced from glucose by microbial fermentation. To produce caffeic acid from inedible cellulose, separate hydrolysis and fermentation (SHF) and simultaneous saccharification and fermentation (SSF) reactions were compared using kraft pulp as lignocellulosic feedstock. Here, a tyrosine-overproducing Escherichia coli strain was metabolically engineered to produce caffeic acid from glucose by introducing the genes encoding a 4-hydroxyphenyllactate 3-hydroxylase (hpaBC) from Pseudomonas aeruginosa and tyrosine ammonia lyase (fevV) from Streptomyces sp. WK-5344. Using the resulting recombinant strain, the maximum yield of caffeic acid in SSF (233 mg/L) far exceeded that by SHF (37.9 mg/L). In the SSF with low cellulase loads (≤2.5 filter paper unit/g glucan), caffeic acid production was markedly increased, while almost no glucose accumulation was detected, indicating that the E. coli cells experienced glucose limitation in this culture condition. Caffeic acid yield was also negatively correlated with the glucose concentration in the fermentation medium. In SHF, the formation of by-product acetate and the accumulation of potential fermentation inhibitors increased significantly with kraft pulp hydrolysate than filter paper hydrolysate. The combination of these inhibitors had synergistic effects on caffeic acid fermentation at low concentrations. With lower loads of cellulase in SSF, less potential fermentation inhibitors (furfural, 5-hydroxymethyfurfural, and 4-hydroxylbenzoic acid) accumulated in the medium. These observations suggest that glucose limitation in SSF is crucial for improving caffeic acid yield, owing to reduced by-product formation and fermentation inhibitor accumulation.

  18. Effect of acetic acid on Saccharomyces carlsbergensis ATCC 6269 batch ethanol production monitored by flow cytometry.

    PubMed

    Freitas, Cláudia; Neves, Elisabete; Reis, Alberto; Passarinho, Paula C; da Silva, Teresa Lopes

    2012-11-01

    Bioethanol produced from lignocellulosic materials has been considered a sustainable alternative fuel. Such type of raw materials have a huge potential, but their hydrolysis into mono-sugars releases toxic compounds such as weak acids, which affect the microorganisms' physiology, inhibiting the growth and ethanol production. Acetic acid (HAc) is the most abundant weak acid in the lignocellulosic materials hydrolysates. In order to understand the physiological changes of Saccharomyces carlsbergensis when fermenting in the presence of different acetic acid (HAc) concentrations, the yeast growth was monitored by multi-parameter flow cytometry at same time that the ethanol production was assessed. The membrane potential stain DiOC(6)(3) fluorescence intensity decreased as the HAc concentration increased, which was attributed to the plasmic membrane potential reduction as a result of the toxic effect of the HAc undissociated form. Nevertheless, the proportion of cells with permeabilized membrane did not increase with the HAc concentration increase. Fermentations ending at lower external pH and higher ethanol concentrations depicted the highest proportions of permeabilized cells and cells with increased reactive oxygen species levels. Flow cytometry allowed monitoring, near real time (at-line), the physiological states of the yeast during the fermentations. The information obtained can be used to optimize culture conditions to improve bioethanol production.

  19. Microbial Production of Glyceric Acid, an Organic Acid That Can Be Mass Produced from Glycerol ▿ †

    PubMed Central

    Habe, Hiroshi; Shimada, Yuko; Yakushi, Toshiharu; Hattori, Hiromi; Ano, Yoshitaka; Fukuoka, Tokuma; Kitamoto, Dai; Itagaki, Masayuki; Watanabe, Kunihiro; Yanagishita, Hiroshi; Matsushita, Kazunobu; Sakaki, Keiji

    2009-01-01

    Glyceric acid (GA), an unfamiliar biotechnological product, is currently produced as a small by-product of dihydroxyacetone production from glycerol by Gluconobacter oxydans. We developed a method for the efficient biotechnological production of GA as a target compound for new surplus glycerol applications in the biodiesel and oleochemical industries. We investigated the ability of 162 acetic acid bacterial strains to produce GA from glycerol and found that the patterns of productivity and enantiomeric GA compositions obtained from several strains differed significantly. The growth parameters of two different strain types, Gluconobacter frateurii NBRC103465 and Acetobacter tropicalis NBRC16470, were optimized using a jar fermentor. G. frateurii accumulated 136.5 g/liter of GA with a 72% d-GA enantiomeric excess (ee) in the culture broth, whereas A. tropicalis produced 101.8 g/liter of d-GA with a 99% ee. The 136.5 g/liter of glycerate in the culture broth was concentrated to 236.5 g/liter by desalting electrodialysis during the 140-min operating time, and then, from 50 ml of the concentrated solution, 9.35 g of GA calcium salt was obtained by crystallization. Gene disruption analysis using G. oxydans IFO12528 revealed that the membrane-bound alcohol dehydrogenase (mADH)-encoding gene (adhA) is required for GA production, and purified mADH from G. oxydans IFO12528 catalyzed the oxidation of glycerol. These results strongly suggest that mADH is involved in GA production by acetic acid bacteria. We propose that GA is potentially mass producible from glycerol feedstock by a biotechnological process. PMID:19837846

  20. Therapeutic potential of n-3 polyunsaturated fatty acids in disease.

    PubMed

    Fetterman, James W; Zdanowicz, Martin M

    2009-07-01

    The potential therapeutic benefits of supplementation with n-3 polyunsaturated fatty acids (PUFAs) in various diseases are reviewed, and the antiinflammatory actions, activity, and potential drug interactions and adverse effects of n-3 PUFAs are discussed. Fish oils are an excellent source of long-chain n-3 PUFAs, such as eicosapentaenoic acid and docosahexaenoic acid. After consumption, n-3 PUFAs can be incorporated into cell membranes and reduce the amount of arachidonic acid available for the synthesis of proinflammatory eicosanoids (e.g., prostaglandins, leukotrienes). Likewise, n-3 PUFAs can also reduce the production of inflammatory cytokines, such as tumor necrosis factor alpha, interleukin-1, and interleukin-6. Considerable research has been conducted to evaluate the potential therapeutic effects of fish oils in numerous conditions, including arthritis, coronary artery disease, inflammatory bowel disease, asthma, and sepsis, all of which have inflammation as a key component of their pathology. Additional investigations into the use of supplementation with fish oils in patients with neural injury, cancer, ocular diseases, and critical illness have recently been conducted. The most commonly reported adverse effects of fish oil supplements are a fishy aftertaste and gastrointestinal upset. When recommending an n-3 PUFA, clinicians should be aware of any possible adverse effect or drug interaction that, although not necessarily clinically significant, may occur, especially for patients who may be susceptible to increased bleeding (e.g., patients taking warfarin). The n-3 PUFAs have been shown to be efficacious in treating and preventing various diseases. The wide variation in dosages and formulations used in studies makes it difficult to recommend dosages for specific treatment goals.

  1. Physiological tolerance and stoichiometric potential of cyanobacteria for hydrocarbon fuel production.

    PubMed

    Kämäräinen, Jari; Knoop, Henning; Stanford, Natalie J; Guerrero, Fernando; Akhtar, M Kalim; Aro, Eva-Mari; Steuer, Ralf; Jones, Patrik R

    2012-11-30

    Cyanobacteria are capable of directly converting sunlight, carbon dioxide and water into hydrocarbon fuel or precursors thereof. Many biological and non-biological factors will influence the ability of such a production system to become economically sustainable. We evaluated two factors in engineerable cyanobacteria which could potentially limit economic sustainability: (i) tolerance of the host to the intended end-product, and (ii) stoichiometric potential for production. Alcohols, when externally added, inhibited growth the most, followed by aldehydes and acids, whilst alkanes were the least inhibitory. The growth inhibition became progressively greater with increasing chain-length for alcohols, whilst the intermediate C6 alkane caused more inhibition than both C3 and C11 alkane. Synechocystis sp. PCC 6803 was more tolerant to some of the tested chemicals than Synechococcus elongatus PCC 7942, particularly ethanol and undecane. Stoichiometric evaluation of the potential yields suggested that there is no difference in the potential productivity of harvestable energy between any of the studied fuels, with the exception of ethylene, for which maximal stoichiometric yield is considerably lower. In summary, it was concluded that alkanes would constitute the best choice metabolic end-product for fuel production using cyanobacteria if high-yielding strains can be developed. Copyright © 2012 Elsevier B.V. All rights reserved.

  2. Dilute sulfuric acid fractionation of Korean food waste for ethanol and lactic acid production by yeast.

    PubMed

    Kim, Yong Seon; Jang, Ji Yeon; Park, Seong Jik; Um, Byung Hwan

    2018-04-01

    Fermentation of food waste biomass can be used to produce biochemicals such as lactic acid and ethanol in a cost-effective manner. Korean food waste (KFW) dewatered by a screw press contains 23.1% glucan on a dry basis and is a potential raw material for the production of ethanol and lactic acid through fermentation. This study was conducted to optimize the dilute acid fractionation conditions for KFW fermentation with respect to the H 2 SO 4 concentration (0-0.8% w/v), temperature (130-190 °C), and residence time (1-128 min) using response surface methodology. Dilute sulfuric acid fractionation was carried out using a 30-mL stainless steel reactor under conditions, and then the dilute acid fractionation was scaled-up in 1-L and 7-L stainless steel reactors under the optimal conditions. The hydrolysate was concentrated, liquid-liquid extracted and neutralized for lactic acid and ethanol production. The highest concentration of glucose obtained from the KFW was 26.4 g/L using fractionation with 0.37% w/v H 2 SO 4 at 156 °C for 123.6 min. Using recombinant Saccharomyces cerevisiae containing a codon-optimized lactate dehydrogenase, the yield of lactic acid and ethanol was 77% of the theoretical yield for 17.4 g/L of fermentable sugar at pH 5.5. Additionally, the yield of ethanol produced by Issatchenkia orientalis was 89% of the theoretical yield for 25 g/L of fermentable sugar at pH 3. Copyright © 2018 Elsevier Ltd. All rights reserved.

  3. Factors Which Increase Acid Production in Milk by Lactobacilli

    PubMed Central

    Huhtanen, C. N.; Williams, W. L.

    1963-01-01

    The stimulation by yeast extract of acid production in milk by various lactobacilli was studied. It was found that supplementing milk with purine and pyrimidine bases and amino acids allowed nearly maximal acid production by Lactobacillus bulgaricus strain 7994, L. acidophilus 4796, 4356, and 4357, and L. leichmannii 326 and 327. Further supplementation with deoxyribotides allowed maximal acid production by L. acidophilus 204, but L. acidophilus 207 required adenosine or adenylic acid. L. casei strain 7469 showed no appreciable response to the amino acids or purine and pyrimidine bases, and is presumed to require an unidentified factor in corn steep liquor. PMID:13955610

  4. Succinic acid production on xylose-enriched biorefinery streams by Actinobacillus succinogenes in batch fermentation

    DOE PAGES

    Salvachua, Davinia; Mohagheghi, Ali; Smith, Holly; ...

    2016-02-02

    Co-production of chemicals from lignocellulosic biomass alongside fuels holds promise for improving the economic outlook of integrated biorefineries. In current biochemical conversion processes that use thermochemical pretreatment and enzymatic hydrolysis, fractionation of hemicellulose-derived and cellulose-derived sugar streams is possible using hydrothermal or dilute acid pretreatment (DAP), which then offers a route to parallel trains for fuel and chemical production from xylose- and glucose-enriched streams. Succinic acid (SA) is a co-product of particular interest in biorefineries because it could potentially displace petroleum-derived chemicals and polymer precursors for myriad applications. Furthermore, SA production from biomass-derived hydrolysates has not yet been fully exploredmore » or developed.« less

  5. Consolidated Bioprocessing for Butyric Acid Production from Rice Straw with Undefined Mixed Culture

    PubMed Central

    Ai, Binling; Chi, Xue; Meng, Jia; Sheng, Zhanwu; Zheng, Lili; Zheng, Xiaoyan; Li, Jianzheng

    2016-01-01

    Lignocellulosic biomass is a renewable source with great potential for biofuels and bioproducts. However, the cost of cellulolytic enzymes limits the utilization of the low-cost bioresource. This study aimed to develop a consolidated bioprocessing without the need of supplementary cellulase for butyric acid production from lignocellulosic biomass. A stirred-tank reactor with a working volume of 21 L was constructed and operated in batch and semi-continuous fermentation modes with a cellulolytic butyrate-producing microbial community. The semi-continuous fermentation with intermittent discharging of the culture broth and replenishment with fresh medium achieved the highest butyric acid productivity of 2.69 g/(L· d). In semi-continuous operation mode, the butyric acid and total carboxylic acid concentrations of 16.2 and 28.9 g/L, respectively, were achieved. Over the 21-day fermentation period, their cumulative yields reached 1189 and 2048 g, respectively, corresponding to 41 and 74% of the maximum theoretical yields based on the amount of NaOH pretreated rice straw fed in. This study demonstrated that an undefined mixed culture-based consolidated bioprocessing for butyric acid production can completely eliminate the cost of supplementary cellulolytic enzymes. PMID:27822203

  6. Consolidated Bioprocessing for Butyric Acid Production from Rice Straw with Undefined Mixed Culture.

    PubMed

    Ai, Binling; Chi, Xue; Meng, Jia; Sheng, Zhanwu; Zheng, Lili; Zheng, Xiaoyan; Li, Jianzheng

    2016-01-01

    Lignocellulosic biomass is a renewable source with great potential for biofuels and bioproducts. However, the cost of cellulolytic enzymes limits the utilization of the low-cost bioresource. This study aimed to develop a consolidated bioprocessing without the need of supplementary cellulase for butyric acid production from lignocellulosic biomass. A stirred-tank reactor with a working volume of 21 L was constructed and operated in batch and semi-continuous fermentation modes with a cellulolytic butyrate-producing microbial community. The semi-continuous fermentation with intermittent discharging of the culture broth and replenishment with fresh medium achieved the highest butyric acid productivity of 2.69 g/(L· d). In semi-continuous operation mode, the butyric acid and total carboxylic acid concentrations of 16.2 and 28.9 g/L, respectively, were achieved. Over the 21-day fermentation period, their cumulative yields reached 1189 and 2048 g, respectively, corresponding to 41 and 74% of the maximum theoretical yields based on the amount of NaOH pretreated rice straw fed in. This study demonstrated that an undefined mixed culture-based consolidated bioprocessing for butyric acid production can completely eliminate the cost of supplementary cellulolytic enzymes.

  7. Targeting arachidonic acid pathway by natural products for cancer prevention and therapy.

    PubMed

    Yarla, Nagendra Sastry; Bishayee, Anupam; Sethi, Gautam; Reddanna, Pallu; Kalle, Arunasree M; Dhananjaya, Bhadrapura Lakkappa; Dowluru, Kaladhar S V G K; Chintala, Ramakrishna; Duddukuri, Govinda Rao

    2016-10-01

    Arachidonic acid (AA) pathway, a metabolic process, plays a key role in carcinogenesis. Hence, AA pathway metabolic enzymes phospholipase A 2 s (PLA 2 s), cyclooxygenases (COXs) and lipoxygenases (LOXs) and their metabolic products, such as prostaglandins and leukotrienes, have been considered novel preventive and therapeutic targets in cancer. Bioactive natural products are a good source for development of novel cancer preventive and therapeutic drugs, which have been widely used in clinical practice due to their safety profiles. AA pathway inhibitory natural products have been developed as chemopreventive and therapeutic agents against several cancers. Curcumin, resveratrol, apigenin, anthocyans, berberine, ellagic acid, eugenol, fisetin, ursolic acid, [6]-gingerol, guggulsteone, lycopene and genistein are well known cancer chemopreventive agents which act by targeting multiple pathways, including COX-2. Nordihydroguaiaretic acid and baicalein can be chemopreventive molecules against various cancers by inhibiting LOXs. Several PLA 2 s inhibitory natural products have been identified with chemopreventive and therapeutic potentials against various cancers. In this review, we critically discuss the possible utility of natural products as preventive and therapeutic agents against various oncologic diseases, including prostate, pancreatic, lung, skin, gastric, oral, blood, head and neck, colorectal, liver, cervical and breast cancers, by targeting AA pathway. Further, the current status of clinical studies evaluating AA pathway inhibitory natural products in cancer is reviewed. In addition, various emerging issues, including bioavailability, toxicity and explorability of combination therapy, for the development of AA pathway inhibitory natural products as chemopreventive and therapeutic agents against human malignancy are also discussed. Copyright © 2016 Elsevier Ltd. All rights reserved.

  8. Rewiring a secondary metabolite pathway towards itaconic acid production in Aspergillus niger.

    PubMed

    Hossain, Abeer H; Li, An; Brickwedde, Anja; Wilms, Lars; Caspers, Martien; Overkamp, Karin; Punt, Peter J

    2016-07-28

    The industrially relevant filamentous fungus Aspergillus niger is widely used in industry for its secretion capabilities of enzymes and organic acids. Biotechnologically produced organic acids promise to be an attractive alternative for the chemical industry to replace petrochemicals. Itaconic acid (IA) has been identified as one of the top twelve building block chemicals which have high potential to be produced by biotechnological means. The IA biosynthesis cluster (cadA, mttA and mfsA) has been elucidated in its natural producer Aspergillus terreus and transferred to A. niger to enable IA production. Here we report the rewiring of a secondary metabolite pathway towards further improved IA production through the overexpression of a putative cytosolic citrate synthase citB in a A. niger strain carrying the IA biosynthesis cluster. We have previously shown that expression of cadA from A. terreus results in itaconic acid production in A. niger AB1.13, albeit at low levels. This low-level production is boosted fivefold by the overexpression of mttA and mfsA in itaconic acid producing AB1.13 CAD background strains. Controlled batch cultivations with AB1.13 CAD + MFS + MTT strains showed increased production of itaconic acid compared with AB1.13 CAD strain. Moreover, preliminary RNA-Seq analysis of an itaconic acid producing AB1.13 CAD strain has led to the identification of the putative cytosolic citrate synthase citB which was induced in an IA producing strain. We have overexpressed citB in a AB1.13 CAD + MFS + MTT strain and by doing so hypothesize to have targeted itaconic acid production to the cytosolic compartment. By overexpressing citB in AB1.13 CAD + MFS + MTT strains in controlled batch cultivations we have achieved highly increased titers of up to 26.2 g/L IA with a productivity of 0.35 g/L/h while no CA was produced. Expression of the IA biosynthesis cluster in Aspergillus niger AB1.13 strain enables IA production. Moreover, in the AB1.13 CAD

  9. Genome-scale model-driven strain design for dicarboxylic acid production in Yarrowia lipolytica.

    PubMed

    Mishra, Pranjul; Lee, Na-Rae; Lakshmanan, Meiyappan; Kim, Minsuk; Kim, Byung-Gee; Lee, Dong-Yup

    2018-03-19

    Recently, there have been several attempts to produce long-chain dicarboxylic acids (DCAs) in various microbial hosts. Of these, Yarrowia lipolytica has great potential due to its oleaginous characteristics and unique ability to utilize hydrophobic substrates. However, Y. lipolytica should be further engineered to make it more competitive: the current approaches are mostly intuitive and cumbersome, thus limiting its industrial application. In this study, we proposed model-guided metabolic engineering strategies for enhanced production of DCAs in Y. lipolytica. At the outset, we reconstructed genome-scale metabolic model (GSMM) of Y. lipolytica (iYLI647) by substantially expanding the previous models. Subsequently, the model was validated using three sets of published culture experiment data. It was finally exploited to identify genetic engineering targets for overexpression, knockout, and cofactor modification by applying several in silico strain design methods, which potentially give rise to high yield production of the industrially relevant long-chain DCAs, e.g., dodecanedioic acid (DDDA). The resultant targets include (1) malate dehydrogenase and malic enzyme genes and (2) glutamate dehydrogenase gene, in silico overexpression of which generated additional NADPH required for fatty acid synthesis, leading to the increased DDDA fluxes by 48% and 22% higher, respectively, compared to wild-type. We further investigated the effect of supplying branched-chain amino acids on the acetyl-CoA turn-over rate which is key metabolite for fatty acid synthesis, suggesting their significance for production of DDDA in Y. lipolytica. In silico model-based strain design strategies allowed us to identify several metabolic engineering targets for overproducing DCAs in lipid accumulating yeast, Y. lipolytica. Thus, the current study can provide a methodological framework that is applicable to other oleaginous yeasts for value-added biochemical production.

  10. Improvement of lactic acid production in Saccharomyces cerevisiae by a deletion of ssb1.

    PubMed

    Lee, Jinsuk J; Crook, Nathan; Sun, Jie; Alper, Hal S

    2016-01-01

    Polylactic acid (PLA) is an important renewable polymer, but current processes for producing its precursor, lactic acid, suffer from process inefficiencies related to the use of bacterial hosts. Therefore, improving the capacity of Saccharomyces cerevisiae to produce lactic acid is a promising approach to improve industrial production of lactic acid. As one such improvement required, the lactic acid tolerance of yeast must be significantly increased. To enable improved tolerance, we employed an RNAi-mediated genome-wide expression knockdown approach as a means to rapidly identify potential genetic targets. In this approach, several gene knockdown targets were identified which confer increased acid tolerance to S. cerevisiae BY4741, of which knockdown of the ribosome-associated chaperone SSB1 conferred the highest increase (52%). This target was then transferred into a lactic acid-overproducing strain of S. cerevisiae CEN.PK in the form of a knockout and the resulting strain demonstrated up to 33% increased cell growth, 58% increased glucose consumption, and 60% increased L-lactic acid production. As SSB1 contains a close functional homolog SSB2 in yeast, this result was counterintuitive and may point to as-yet-undefined functional differences between SSB1 and SSB2 related to lactic acid production. The final strain produced over 50 g/L of lactic acid in under 60 h of fermentation.

  11. Developing Potential Energy Curves of Acidic and Basic Amino Acids Using Quantum Computational Techniques

    NASA Astrophysics Data System (ADS)

    de Guzman, C. P.; Andrianarijaona, M.; Yoshida, Y.; Kim, K.; Andrianarijaona, V. M.

    2017-04-01

    Proteins are made out of long chains of amino acids and are an integral part of many tasks of a cell. Because the function of a protein is caused by its structure, even minute changes in the molecular geometry of the protein can have large effects on how the protein can be used. This study investigated how manipulations in the structure of acidic and basic amino acids affected their potential energy. Acidic and basic amino acids were chosen because prior studies have suggested that the ionizable side chains of these amino acids can be very influential on a molecule's prefered conformation. Each atom in the molecule was pulled along x, y, and z axis to see how different types of changes affect the potential energy of the whole structure. The results of our calculations, which were done using ORCA, emphasize the vibronic couplings. The aggregated data was used to create a data set of potential energy curves to better understand the quantum dynamic properties of acidic and basic amino acids (preliminary data was presented in http://meetings.aps.org/Meeting/MAR16/Session/M1.273 andhttp://meetings.aps.org/Meeting/FWS16/Session/F2.6).

  12. Production of succinic acid by metabolically engineered microorganisms.

    PubMed

    Ahn, Jung Ho; Jang, Yu-Sin; Lee, Sang Yup

    2016-12-01

    Succinic acid (SA) has been recognized as one of the most important bio-based building block chemicals due to its numerous potential applications. For the economical bio-based production of SA, extensive research works have been performed on developing microbial strains by metabolic engineering as well as fermentation and downstream processes. Here we review metabolic engineering strategies applied for bio-based production of SA using representative microorganisms, including Saccharomyces cerevisiae, Pichia kudriavzevii, Escherichia coli, Mannheimia succiniciproducens, Basfia succiniciproducens, Actinobacillus succinogenes, and Corynebacterium glutamicum. In particular, strategies employed for developing engineered strains of these microorganisms leading to the best performance indices (titer, yield, and productivity) are showcased based on the published papers as well as patents. Those processes currently under commercialization are also analyzed and future perspectives are provided. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. Reducing the potential for processing contaminant formation in cereal products.

    PubMed

    Curtis, Tanya Y; Postles, Jennifer; Halford, Nigel G

    2014-05-01

    Processing contaminants may be defined as substances that are produced in a food when it is cooked or processed, are not present or are present at much lower concentrations in the raw, unprocessed food, and are undesirable either because they have an adverse effect on product quality or because they are potentially harmful. The presence of very low levels of processing contaminants in common foods is becoming an increasingly important issue for the food industry, as developments in analytical techniques and equipment bring foods under closer and closer scrutiny. This review considers the formation of lipid oxidation products, hydrogenation of polyunsaturated fatty acids to prevent lipid oxidation and the associated risk of trans fatty acid formation. The formation of acrylamide in the Maillard reaction is described, as well as the genetic and agronomic approaches being taken to reduce the acrylamide-forming potential of cereal grain. The multiple routes for the formation of furan and associated chemicals, including hydroxymethylfurfuryl, are also described. The evolving regulatory and public perception situations for these processing contaminants and their implications for the cereal supply chain are discussed, emphasising the need for cereal breeders to engage with the contaminants issue.

  14. Novel homologous lactate transporter improves L-lactic acid production from glycerol in recombinant strains of Pichia pastoris.

    PubMed

    de Lima, Pollyne Borborema Almeida; Mulder, Kelly Cristina Leite; Melo, Nadiele Tamires Moreira; Carvalho, Lucas Silva; Menino, Gisele Soares; Mulinari, Eduardo; de Castro, Virgilio H; Dos Reis, Thaila F; Goldman, Gustavo Henrique; Magalhães, Beatriz Simas; Parachin, Nádia Skorupa

    2016-09-15

    Crude glycerol is the main byproduct of the biodiesel industry. Although it can have different applications, its purification is costly. Therefore, in this study a biotechnological route has been proposed for further utilization of crude glycerol in the fermentative production of lactic acid. This acid is largely utilized in food, pharmaceutical, textile, and chemical industries, making it the hydroxycarboxylic acid with the highest market potential worldwide. Currently, industrial production of lactic acid is done mainly using sugar as the substrate. Thus here, for the first time, Pichia pastoris has been engineered for heterologous L-lactic acid production using glycerol as a single carbon source. For that, the Bos taurus lactate dehydrogenase gene was introduced into P. pastoris. Moreover, a heterologous and a novel homologous lactate transporter have been evaluated for L-lactic acid production. Batch fermentation of the P. pastoris X-33 strain producing LDHb allowed for lactic acid production in this yeast. Although P. pastoris is known for its respiratory metabolism, batch fermentations were performed with different oxygenation levels, indicating that lower oxygen availability increased lactic acid production by 20 %, pushing the yeast towards a fermentative metabolism. Furthermore, a newly putative lactate transporter from P. pastoris named PAS has been identified by search similarity with the lactate transporter from Saccharomyces cerevisiae Jen1p. Both heterologous and homologous transporters, Jen1p and PAS, were evaluated in one strain already containing LDH activity. Fed-batch experiments of P. pastoris strains carrying the lactate transporter were performed with the batch phase at aerobic conditions followed by an aerobic oxygen-limited phase where production of lactic acid was favored. The results showed that the strain containing PAS presented the highest lactic acid titer, reaching a yield of approximately 0.7 g/g. We showed that P. pastoris has a

  15. Amino acid catabolism-directed biofuel production in Clostridium sticklandii: An insight into model-driven systems engineering.

    PubMed

    Sangavai, C; Chellapandi, P

    2017-12-01

    Model-driven systems engineering has been more fascinating process for the microbial production of biofuel and bio-refineries in chemical and pharmaceutical industries. Genome-scale modeling and simulations have been guided for metabolic engineering of Clostridium species for the production of organic solvents and organic acids. Among them, Clostridium sticklandii is one of the potential organisms to be exploited as a microbial cell factory for biofuel production. It is a hyper-ammonia producing bacterium and is able to catabolize amino acids as important carbon and energy sources via Stickland reactions and the development of the specific pathways. Current genomic and metabolic aspects of this bacterium are comprehensively reviewed herein, which provided information for learning about protein catabolism-directed biofuel production. It has a metabolic potential to drive energy and direct solventogenesis as well as acidogenesis from protein catabolism. It produces by-products such as ethanol, acetate, n -butanol, n -butyrate and hydrogen from amino acid catabolism. Model-driven systems engineering of this organism would improve the performance of the industrial sectors and enhance the industrial economy by using protein-based waste in environment-friendly ways.

  16. 40 CFR 721.10125 - Alkenedioic acid, dialkyl ester, reaction products with polyaminocarbomonocycle and alkenoic acid...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ..., reaction products with polyaminocarbomonocycle and alkenoic acid alkyl ester (generic). 721.10125 Section... Substances § 721.10125 Alkenedioic acid, dialkyl ester, reaction products with polyaminocarbomonocycle and.... (1) The chemical substances identified generically as alkenedioic acid, dialkyl ester, reaction...

  17. 40 CFR 721.10125 - Alkenedioic acid, dialkyl ester, reaction products with polyaminocarbomonocycle and alkenoic acid...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ..., reaction products with polyaminocarbomonocycle and alkenoic acid alkyl ester (generic). 721.10125 Section... Substances § 721.10125 Alkenedioic acid, dialkyl ester, reaction products with polyaminocarbomonocycle and.... (1) The chemical substances identified generically as alkenedioic acid, dialkyl ester, reaction...

  18. Protein and metabolic engineering for the production of organic acids.

    PubMed

    Liu, Jingjing; Li, Jianghua; Shin, Hyun-Dong; Liu, Long; Du, Guocheng; Chen, Jian

    2017-09-01

    Organic acids are natural metabolites of living organisms. They have been widely applied in the food, pharmaceutical, and bio-based materials industries. In recent years, biotechnological routes to organic acids production from renewable raw materials have been regarded as very promising approaches. In this review, we provide an overview of current developments in the production of organic acids using protein and metabolic engineering strategies. The organic acids include propionic acid, pyruvate, itaconic acid, succinic acid, fumaric acid, malic acid and citric acid. We also expect that rapid developments in the fields of systems biology and synthetic biology will accelerate protein and metabolic engineering for microbial organic acid production in the future. Copyright © 2017. Published by Elsevier Ltd.

  19. [CONTENT OF TRANS FATTY ACIDS IN FOOD PRODUCTS IN SPAIN].

    PubMed

    Robledo de Dios, Teresa; Dal Re Saavedra, M Ángeles; Villar Villalba, Carmen; Pérez-Farinós, Napoleón

    2015-09-01

    trans fatty acids are associated to several health disorders, as ischemic heart disease or diabetes mellitus. to assess the content of trans fatty acids in products in Spain, and the percentage of trans fatty acids respecting total fatty acids. 443 food products were acquired in Spain, and they were classified into groups. The content in fatty acids was analyzed using gas chromatography. Estimates of central tendency and variability of the content of trans fatty acids in each food group were computed (in g of trans fatty acids/100 g of product). The percentage of trans fatty acids respecting total fatty acids was calculated in each group. 443 products were grouped into 42 groups. Median of trans fatty acids was less than 0.55 g / 100 g of product in all groups except one. 83 % of groups had less than 2 % of trans fatty acids, and 71 % of groups had less than 1 %. the content of trans fatty acids in Spain is low, and it currently doesn't play a public health problem. Copyright AULA MEDICA EDICIONES 2014. Published by AULA MEDICA. All rights reserved.

  20. Free lactic acid production under acidic conditions by lactic acid bacteria strains: challenges and future prospects.

    PubMed

    Singhvi, Mamata; Zendo, Takeshi; Sonomoto, Kenji

    2018-05-26

    Lactic acid (LA) is an important platform chemical due to its significant applications in various fields and its use as a monomer for the production of biodegradable poly(lactic acid) (PLA). Free LA production is required to get rid of CaSO 4 , a waste material produced during fermentation at neutral pH which will lead to easy purification of LA required for the production of biodegradable PLA. Additionally, there is no need to use corrosive acids to release free LA from the calcium lactate produced during neutral fermentation. To date, several attempts have been made to improve the acid tolerance of lactic acid bacteria (LAB) by using both genome-shuffling approaches and rational design based on known mechanisms of LA tolerance and gene deletion in yeast strains. However, the lack of knowledge and the complexity of acid-tolerance mechanisms have made it challenging to generate LA-tolerant strains by simply modifying few target genes. Currently, adaptive evolution has proven an efficient strategy to improve the LA tolerance of individual/engineered strains. The main objectives of this article are to summarize the conventional biotechnological LA fermentation processes to date, assess their overall economic and environmental cost, and to introduce modern LA fermentation strategies for free LA production. In this review, we provide a broad overview of free LA fermentation processes using robust LAB that can ferment in acidic environments, the obstacles to these processes and their possible solutions, and the impact on future development of free LA fermentation processes commercially.

  1. Control of Salmonella Enteritidis in turkeys using organic acids and competitive exclusion product.

    PubMed

    Milbradt, E L; Zamae, J R; Araújo Júnior, J P; Mazza, P; Padovani, C R; Carvalho, V R; Sanfelice, C; Rodrigues, D M; Okamoto, A S; Andreatti Filho, R L

    2014-08-01

    To evaluate the use of organic acids (OAs) and competitive exclusion (CE) product administered continuously in the feed and transiently in drinking water on the control of Salmonella enterica subspecie enterica serotype Enteritidis (SE) prior to slaughter. The influence of treatments were evaluated on pH, population of the lactic acid bacteria (LAB) and bacteria of the family Enterobacteriaceae, concentration of volatile fatty acids and SE colonization in the crop and caecum. The birds were challenged with SE 24 h before being slaughtered, and then, the caeca and crop were removed and subjected to SE counts. Continuous administration of OAs reduced the population of bacteria from the Enterobacteriaceae family in both crop and caecum, positively influenced the butyric acid concentration and reduced SE colonization in the caecum. The diet supplemented with CE product positively influenced the quantity of LAB in the crop and caecum, elevated the butyric acid concentration and reduced both Enterobacteriaceae quantity and SE colonization in the caecum. There was no effect from administering the treatments via drinking water on the variables measured. Continuous supplementation in feed with OAs and CE product reduced SE colonization of the caeca. Supplementation of OAs and CE product in diet to turkeys can reduce the SE load, potentially leading to a lower contamination risk of meat during slaughter. © 2014 The Society for Applied Microbiology.

  2. Naphthylacetic Acid and Tea Polyphenol Application Promote Biomass and Lipid Production of Nervonic Acid-Producing Microalgae.

    PubMed

    Xu, Feng; Fan, Yong; Miao, Fuhong; Hu, Guang-Rong; Sun, Juan; Yang, Guofeng; Li, Fu-Li

    2018-01-01

    Mychonastes afer HSO-3-1 is a potential producer of nervonic acid, which could be accumulated to 2-3% of dry cell weight. Improving the productivity of nervonic acid is critical to promote the commercialization of this product. In this study, 1-naphthylacetic acid (NAA) and tea polyphenol (TP) were selected as bioactive additives to stimulate the growth of M. afer . Supplementing NAA in the early growth stage and TP in the middle and late growth stage led to improved lipid accumulation in M. afer . The cultures supplemented with TP at the late growth stage maintained higher photosynthetic efficiency than the control groups without TP. Furthermore, the intracellular reactive oxygen species (ROS) accumulations in M. afer supplemented with 500 mg/L of TP was 63% lower than the control group. A linear relationship ( R 2 = 0.899) between the values of Fv/Fm and ROS accumulation was established. We hypothesize supplement of bioactive additives at different growth stage could promote the cell growth rate and nervonic acid productivity of M. afer by retrieving intracellular ROS level. Further analysis of photosynthetic system II (PSII) protein in M. afer cultured in presence of NAA and TP indicated the levels of D1 and D2 proteins, the core skeleton proteins of PSII, showed 33.3 and 25.6% higher than the control group. CP43 protein, a critical module in PSII repair cycle, decreased significantly. These implied that TP possesses the function of slowing down the damage of PSII by scavenging excess intracellular ROS.

  3. Bacteriocins from lactic acid bacteria: production, purification, and food applications.

    PubMed

    De Vuyst, Luc; Leroy, Frédéric

    2007-01-01

    In fermented foods, lactic acid bacteria (LAB) display numerous antimicrobial activities. This is mainly due to the production of organic acids, but also of other compounds, such as bacteriocins and antifungal peptides. Several bacteriocins with industrial potential have been purified and characterized. The kinetics of bacteriocin production by LAB in relation to process factors have been studied in detail through mathematical modeling and positive predictive microbiology. Application of bacteriocin-producing starter cultures in sourdough (to increase competitiveness), in fermented sausage (anti-listerial effect), and in cheese (anti-listerial and anti-clostridial effects), have been studied during in vitro laboratory fermentations as well as on pilot-scale level. The highly promising results of these studies underline the important role that functional, bacteriocinogenic LAB strains may play in the food industry as starter cultures, co-cultures, or bioprotective cultures, to improve food quality and safety. In addition, antimicrobial production by probiotic LAB might play a role during in vivo interactions occurring in the human gastrointestinal tract, hence contributing to gut health.

  4. Fumaric acid production using renewable resources from biodiesel and cane sugar production processes.

    PubMed

    Papadaki, Aikaterini; Papapostolou, Harris; Alexandri, Maria; Kopsahelis, Nikolaos; Papanikolaou, Seraphim; de Castro, Aline Machado; Freire, Denise M G; Koutinas, Apostolis A

    2018-04-13

    The microbial production of fumaric acid by Rhizopus arrhizus NRRL 2582 has been evaluated using soybean cake from biodiesel production processes and very high polarity (VHP) sugar from sugarcane mills. Soybean cake was converted into a nutrient-rich hydrolysate via a two-stage bioprocess involving crude enzyme production via solid state fermentations (SSF) of either Aspergillus oryzae or R. arrhizus cultivated on soybean cake followed by enzymatic hydrolysis of soybean cake. The soybean cake hydrolysate produced using crude enzymes derived via SSF of R. arrhizus was supplemented with VHP sugar and evaluated using different initial free amino nitrogen (FAN) concentrations (100, 200, and 400 mg/L) in fed-batch cultures for fumaric acid production. The highest fumaric acid concentration (27.3 g/L) and yield (0.7 g/g of total consumed sugars) were achieved when the initial FAN concentration was 200 mg/L. The combination of VHP sugar with soybean cake hydrolysate derived from crude enzymes produced by SSF of A. oryzae at 200 mg/L initial FAN concentration led to the production of 40 g/L fumaric acid with a yield of 0.86 g/g of total consumed sugars. The utilization of sugarcane molasses led to low fumaric acid production by R. arrhizus, probably due to the presence of various minerals and phenolic compounds. The promising results achieved through the valorization of VHP sugar and soybean cake suggest that a focused study on molasses pretreatment could lead to enhanced fumaric acid production.

  5. Butyric acid stimulates bovine neutrophil functions and potentiates the effect of platelet activating factor.

    PubMed

    Carretta, M D; Hidalgo, A I; Burgos, J; Opazo, L; Castro, L; Hidalgo, M A; Figueroa, C D; Taubert, A; Hermosilla, C; Burgos, R A

    2016-08-01

    Increased short-chain fatty acid (SCFA) production is associated with subacute ruminal acidosis (SARA) and activation of inflammatory processes. In humans and rodents, SCFAs modulate inflammatory responses in the gut via free fatty acid receptor 2 (FFA2). In bovines, butyric acid is one of the most potent FFA2 agonists. Its expression in bovine neutrophils has recently been demonstrated, suggesting a role in innate immune response in cattle. This study aimed to evaluate if butyric acid modulates oxidative and non-oxidative functions or if it can potentiate other inflammatory mediators in bovine neutrophils. Our results showed that butyric acid can activate bovine neutrophils, inducing calcium (Ca(2+)) influx and mitogen-activated protein kinase (MAPK) phosphorylation, two second messengers involved in FFA2 activation. Ca(2+) influx induced by butyric acid was dependent on the extracellular and intracellular Ca(2+) source and phospholipase C (PLC) activation. Butyric acid alone had no significant effect on reactive oxygen species (ROS) production and chemotaxis; however, a priming effect on platelet-activating factor (PAF), a potent inflammatory mediator, was observed. Butyric acid increased CD63 expression and induced the release of neutrophil granule markers matrix metalloproteinase-9 (MMP-9) and lactoferrin. Finally, we observed that butyric acid induced neutrophil extracellular trap (NET) formation without affecting cellular viability. These findings suggest that butyric acid, a component of the ruminal fermentative process, can modulate the innate immune response of ruminants. Copyright © 2016 Elsevier B.V. All rights reserved.

  6. Succinic acid production from acid hydrolysate of corn fiber by Actinobacillus succinogenes.

    PubMed

    Chen, Kequan; Jiang, Min; Wei, Ping; Yao, Jiaming; Wu, Hao

    2010-01-01

    Dilute acid hydrolysate of corn fiber was used as carbon source for the production of succinic acid by Actinobacillus succinogenes NJ113. The optimized hydrolysis conditions were obtained by orthogonal experiments. When corn fiber particles were of 20 mesh in size and treated with 1.0% sulfuric acid at 121 degrees C for 2 h, the total sugar yield could reach 63.3%. It was found that CaCO(3) neutralization combined with activated carbon adsorption was an effective method to remove fermentation inhibitors especially furfural that presented in the acid hydrolysate of corn fiber. Only 5.2% of the total sugar was lost, while 91.9% of furfural was removed. The yield of succinic acid was higher than 72.0% with the detoxified corn fiber hydrolysate as the carbon source in anaerobic bottles or 7.5 L fermentor cultures. It was proved that the corn fiber hydrolysate could be an alternative to glucose for the production of succinic acid by A. succinogenes NJ113.

  7. Engineered Production of Short Chain Fatty Acid in Escherichia coli Using Fatty Acid Synthesis Pathway

    PubMed Central

    Jawed, Kamran; Mattam, Anu Jose; Fatma, Zia; Wajid, Saima; Abdin, Malik Z.; Yazdani, Syed Shams

    2016-01-01

    Short-chain fatty acids (SCFAs), such as butyric acid, have a broad range of applications in chemical and fuel industries. Worldwide demand of sustainable fuels and chemicals has encouraged researchers for microbial synthesis of SCFAs. In this study we compared three thioesterases, i.e., TesAT from Anaerococcus tetradius, TesBF from Bryantella formatexigens and TesBT from Bacteroides thetaiotaomicron, for production of SCFAs in Escherichia coli utilizing native fatty acid synthesis (FASII) pathway and modulated the genetic and bioprocess parameters to improve its yield and productivity. E. coli strain expressing tesBT gene yielded maximum butyric acid titer at 1.46 g L-1, followed by tesBF at 0.85 g L-1 and tesAT at 0.12 g L-1. The titer of butyric acid varied significantly depending upon the plasmid copy number and strain genotype. The modulation of genetic factors that are known to influence long chain fatty acid production, such as deletion of the fadD and fadE that initiates the fatty acid degradation cycle and overexpression of fadR that is a global transcriptional activator of fatty acid biosynthesis and repressor of degradation cycle, did not improve the butyric acid titer significantly. Use of chemical inhibitor cerulenin, which restricts the fatty acid elongation cycle, increased the butyric acid titer by 1.7-fold in case of TesBF, while it had adverse impact in case of TesBT. In vitro enzyme assay indicated that cerulenin also inhibited short chain specific thioesterase, though inhibitory concentration varied according to the type of thioesterase used. Further process optimization followed by fed-batch cultivation under phosphorous limited condition led to production of 14.3 g L-1 butyric acid and 17.5 g L-1 total free fatty acid at 28% of theoretical yield. This study expands our understanding of SCFAs production in E. coli through FASII pathway and highlights role of genetic and process optimization to enhance the desired product. PMID:27466817

  8. Biomass production of multipopulation microalgae in open air pond for biofuel potential.

    PubMed

    Selvakumar, P; Umadevi, K

    2016-04-01

    Biodiesel gains attention as it is made from renewable resources and has considerable environmental benefits. The present investigation has focused on large scale cultivation of multipopulation microalgae in open air pond using natural sea water without any additional nutritive supplements for low cost biomass production as a possible source of biofuel in large scale. Open air algal pond attained average chlorophyll concentration of 11.01 µg/L with the maximum of 43.65 µg/L as well as a higher lipid concentration of 18% (w/w) with lipid content 9.3 mg/L on the 10th day of the culture; and maximum biomass of 0.36 g/L on the 7th day of the culture. Composition analysis of fatty acid methyl ester (FAME) was performed by gas chromatography and mass spectrometry (GCMS). Multipopulation of algal biomass had 18% of total lipid content with 55% of total saturated fatty acids (SFA), 35.3% of monounsaturated fatty acids (MUFA) and 9.7% of polyunsaturated fatty acids (PUFA), revealing a potential source of biofuel production at low cost.

  9. Sugar-Based Ethanol Biorefinery: Ethanol, Succinic Acid and By-Product Production

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

    Donal F. Day

    2009-03-31

    The work conducted in this project is an extension of the developments itemized in DE-FG-36-04GO14236. This program is designed to help the development of a biorefinery based around a raw sugar mill, which in Louisiana is an underutilized asset. Some technical questions were answered regarding the addition of a biomass to ethanol facility to existing sugar mills. The focus of this work is on developing technology to produce ethanol and valuable by-products from bagasse. Three major areas are addressed, feedstock storage, potential by-products and the technology for producing ethanol from dilute ammonia pre-treated bagasse. Sugar mills normally store bagasse inmore » a simple pile. During the off season there is a natural degradation of the bagasse, due to the composting action of microorganisms in the pile. This has serious implications if bagasse must be stored to operate a bagasse/biorefinery for a 300+ day operating cycle. Deterioration of the fermentables in bagasse was found to be 6.5% per month, on pile storage. This indicates that long term storage of adequate amounts of bagasse for year-round operation is probably not feasible. Lignin from pretreatment seemed to offer a potential source of valuable by-products. Although a wide range of phenolic compounds were present in the effluent from dilute ammonia pretreatment, the concentrations of each (except for benzoic acid) were too low to consider for extraction. The cellulosic hydrolysis system was modified to produce commercially recoverable quantities of cellobiose, which has a small but growing market in the food process industries. A spin-off of this led to the production of a specific oligosaccharide which appears to have both medical and commercial implications as a fungal growth inhibitor. An alternate use of sugars produced from biomass hydrolysis would be to produce succinic acid as a chemical feedstock for other conversions. An organism was developed which can do this bioconversion, but the

  10. In situ biodiesel production from greasy sewage sludge using acid and enzymatic catalysts.

    PubMed

    Sangaletti-Gerhard, Naiane; Cea, Mara; Risco, Vicky; Navia, Rodrigo

    2015-03-01

    This study proposes to select the most appropriate sewage sludge (greasy, primary and secondary) for in situ transesterification and to compare the technical, economic and energetic performance of an enzymatic catalyst (Novozym®435) with sulfuric acid. Greasy sludge was selected as feedstock for biodiesel production due to its high lipid content (44.4%) and low unsaponifiable matter. Maximum methyl esters yield (61%) was reached when processing the wet sludge using sulfuric acid as catalyst and n-hexane, followed by dried-greasy sludge catalyzed by Novozym®435 (57% methyl esters). Considering the economic point of view, the process using acid catalyst was more favorable compared to Novozym®435 catalyst due to the high cost of lipase. In general, greasy sludge (wet or dried) showed high potential to produce biodiesel. However, further technical adjustments are needed to make biodiesel production by in situ transesterification using acid and enzymatic catalyst feasible. Copyright © 2014 Elsevier Ltd. All rights reserved.

  11. Evaluation of the potential of 9 Nannochloropsis strains for biodiesel production.

    PubMed

    Ma, Yubin; Wang, Zhiyao; Yu, Changjiang; Yin, Yehu; Zhou, Gongke

    2014-09-01

    Nannochloropsis have attracted sustained interest from algal biodiesel researchers due to their high biomass accumulation rate and high lipid content. There are six recognized species in the Nannochloropsis genus that are phylogenetically divided into Nannochloropsis gaditana, Nannochloropsis salina, Nannochloropsis granulata, Nannochloropsis limnetica, Nannochloropsis oceanica and Nannochloropsis oculata. In this study, the potential of 9 Nannochloropsis species from the 6 genus for biodiesel production was evaluated by determining their growth rate, biomass accumulation, lipid productivity, lipid composition, fatty acid profiles and biodiesel properties. The results showed that the best strain was N. oceanica IMET1, with lipid productivity of 158.76 ± 13.83 mg L(-1)day(-1), TAG production of 1.67 ± 0.20 g/L, favorable fatty acid profiles of C16-C18 (56.62 ± 1.96%) as well as suitable biodiesel properties of higher cetane number (54.61 ± 0.25), lower iodine number (104.85 ± 2.80 g I2/100g) and relative low cloud point (3.45 ± 0.50°C). N. oceanica IMET1 could be consider as valuable feedstock for microalgal biodiesel production. Copyright © 2014 Elsevier Ltd. All rights reserved.

  12. The Potential Role of Seaweeds in the Natural Manipulation of Rumen Fermentation and Methane Production.

    PubMed

    Maia, Margarida R G; Fonseca, António J M; Oliveira, Hugo M; Mendonça, Carla; Cabrita, Ana R J

    2016-08-30

    This study is the first to evaluate the effects of five seaweeds (Ulva sp., Laminaria ochroleuca, Saccharina latissima, Gigartina sp., and Gracilaria vermiculophylla) on gas and methane production and ruminal fermentation parameters when incubated in vitro with two substrates (meadow hay and corn silage) for 24 h. Seaweeds led to lower gas production, with Gigartina sp. presenting the lowest value. When incubated with meadow hay, Ulva sp., Gigartina sp. and G. vermiculophylla decreased methane production, but with corn silage, methane production was only decreased by G. vermiculophylla. With meadow hay, L. ochroleuca and S. latissima promoted similar methane production as the control, but with corn silage, L. ochroleuca increased it. With the exception of S. latissima, all seaweeds promoted similar levels of total volatile fatty acid production. The highest proportion of acetic acid was produced with Ulva sp., G. vermiculophylla, and S. latissima; the highest proportion of butyric acid with the control and L. ochroleuca; and the highest proportion of iso-valeric acid with Gigartina sp. These results reveal the potential of seaweeds to mitigate ruminal methane production and the importance of the basal diet. To efficiently use seaweeds as feed ingredients with nutritional and environmental benefits, more research is required to determine the mechanisms underlying seaweed and substrate interactions.

  13. The Potential Role of Seaweeds in the Natural Manipulation of Rumen Fermentation and Methane Production

    PubMed Central

    Maia, Margarida R. G.; Fonseca, António J. M.; Oliveira, Hugo M.; Mendonça, Carla; Cabrita, Ana R. J.

    2016-01-01

    This study is the first to evaluate the effects of five seaweeds (Ulva sp., Laminaria ochroleuca, Saccharina latissima, Gigartina sp., and Gracilaria vermiculophylla) on gas and methane production and ruminal fermentation parameters when incubated in vitro with two substrates (meadow hay and corn silage) for 24 h. Seaweeds led to lower gas production, with Gigartina sp. presenting the lowest value. When incubated with meadow hay, Ulva sp., Gigartina sp. and G. vermiculophylla decreased methane production, but with corn silage, methane production was only decreased by G. vermiculophylla. With meadow hay, L. ochroleuca and S. latissima promoted similar methane production as the control, but with corn silage, L. ochroleuca increased it. With the exception of S. latissima, all seaweeds promoted similar levels of total volatile fatty acid production. The highest proportion of acetic acid was produced with Ulva sp., G. vermiculophylla, and S. latissima; the highest proportion of butyric acid with the control and L. ochroleuca; and the highest proportion of iso-valeric acid with Gigartina sp. These results reveal the potential of seaweeds to mitigate ruminal methane production and the importance of the basal diet. To efficiently use seaweeds as feed ingredients with nutritional and environmental benefits, more research is required to determine the mechanisms underlying seaweed and substrate interactions. PMID:27572486

  14. The Potential Role of Seaweeds in the Natural Manipulation of Rumen Fermentation and Methane Production

    NASA Astrophysics Data System (ADS)

    Maia, Margarida R. G.; Fonseca, António J. M.; Oliveira, Hugo M.; Mendonça, Carla; Cabrita, Ana R. J.

    2016-08-01

    This study is the first to evaluate the effects of five seaweeds (Ulva sp., Laminaria ochroleuca, Saccharina latissima, Gigartina sp., and Gracilaria vermiculophylla) on gas and methane production and ruminal fermentation parameters when incubated in vitro with two substrates (meadow hay and corn silage) for 24 h. Seaweeds led to lower gas production, with Gigartina sp. presenting the lowest value. When incubated with meadow hay, Ulva sp., Gigartina sp. and G. vermiculophylla decreased methane production, but with corn silage, methane production was only decreased by G. vermiculophylla. With meadow hay, L. ochroleuca and S. latissima promoted similar methane production as the control, but with corn silage, L. ochroleuca increased it. With the exception of S. latissima, all seaweeds promoted similar levels of total volatile fatty acid production. The highest proportion of acetic acid was produced with Ulva sp., G. vermiculophylla, and S. latissima; the highest proportion of butyric acid with the control and L. ochroleuca; and the highest proportion of iso-valeric acid with Gigartina sp. These results reveal the potential of seaweeds to mitigate ruminal methane production and the importance of the basal diet. To efficiently use seaweeds as feed ingredients with nutritional and environmental benefits, more research is required to determine the mechanisms underlying seaweed and substrate interactions.

  15. Production and Recovery of Pyruvic Acid: Recent Advances

    NASA Astrophysics Data System (ADS)

    Pal, Dharm; Keshav, Amit; Mazumdar, Bidyut; Kumar, Awanish; Uslu, Hasan

    2017-12-01

    Pyruvic acid is an important keto-carboxylic acid and can be manufactured by both chemical synthesis and biotechnological routes. In the present paper an overview of recent developments and challenges in various existing technique for the production and recovery of pyruvic acid from fermentation broth or from waste streams has been presented. The main obstacle in biotechnological production of pyruvic acid is development of suitable microorganism which can provide high yield and selectivity. On the other hand, technical limitation in recovery of pyruvic acid from fermentation broth is that, it could not be separated as other carboxylic acid in the form of salts by addition of alkali. Besides, pyruvic acid cannot be crystallized. Commercial separation by distillation is very expensive because pyruvic acid decomposes at higher temperature. It is also chemically reactive due to its peculiar molecular structure and has tendency to polymerize. Thus, at high concentration the various type of reaction leads to lower yield of the product, and hence, conventional methods are not favorable. Alternate separation technologies viable to both synthetic and biological routes are the current research areas. Latest techniques such as reactive extraction is new to the field of recovery of pyruvic acid. Recent development and future prospects in downstream processing of biochemically produced pyruvic acids has been discussed in this review article.

  16. PRODUCTION OF TRIFLUOROACETIC ACID COMPOUNDS

    DOEpatents

    Haworth, W.N.; Stacey, M.

    1949-08-30

    A process is described for the preparation of trifluoroacetic acid. Acetone vapor diluted wlth nitrogen and fluorine also diluted with nltrogen are fed separately at a temperature of about 210 deg C into a reaction vessel containing a catalyst mass selected from-the group consisting of silver and gold. The temperature in the reaction vessel is maintained in the range of 200 deg to 250 deg C. The reaction product, trifluoroacetyl fluoride, is absorbed in aqueous alkali solution. Trifluoroacetic acid is recovered from the solution by acidification wlth an acid such as sulfuric followed by steam distillation.

  17. Production of xylitol from corn cob hydrolysate through acid and enzymatic hydrolysis by yeast

    NASA Astrophysics Data System (ADS)

    Mardawati, Efri; Andoyo, R.; Syukra, K. A.; Kresnowati, MTAP; Bindar, Y.

    2018-03-01

    The abundance of corn production in Indonesia offers the potential for its application as the raw material for biorefinery process. The hemicellulose content in corn cobs can be considered to be used as a raw material for xylitol production. The purpose of this research was to study the effect of hydrolysis methods for xylitol production and the effect of the hydrolyzed corn cobs to produce xylitol through fermentation. Hydrolysis methods that would be evaluated were acid and enzymatic hydrolysis. The result showed that the xylitol yield of fermented solution using enzymatic hydrolysates was 0.216 g-xylitol/g-xylose, which was higher than the one that used acid hydrolysates, which was 0.100 g-xylitol/g-xylose. Moreover, the specific growth rate of biomass in fermentation using enzymatic hydrolysates was also higher than the one that used acid hydrolysates, 0.039/h compared to 0.0056/h.

  18. Enhanced d-lactic acid production by recombinant Saccharomyces cerevisiae following optimization of the global metabolic pathway.

    PubMed

    Yamada, Ryosuke; Wakita, Kazuki; Mitsui, Ryosuke; Ogino, Hiroyasu

    2017-09-01

    Utilization of renewable feedstocks for the production of bio-based chemicals such as d-lactic acid by engineering metabolic pathways in the yeast Saccharomyces cerevisiae has recently become an attractive option. In this study, to realize efficient d-lactic acid production by S. cerevisiae, the expression of 12 glycolysis-related genes and the Leuconostoc mesenteroides d-LDH gene was optimized using a previously developed global metabolic engineering strategy, and repeated batch fermentation was carried out using the resultant strain YPH499/dPdA3-34/DLDH/1-18. Stable d-lactic acid production through 10 repeated batch fermentations was achieved using YPH499/dPdA3-34/DLDH/1-18. The average d-lactic acid production, productivity, and yield with 10 repeated batch fermentations were 60.3 g/L, 2.80 g/L/h, and 0.646, respectively. The present study is the first report of the application of a global metabolic engineering strategy for bio-based chemical production, and it shows the potential for efficient production of such chemicals by global metabolic engineering of the yeast S. cerevisiae. Biotechnol. Bioeng. 2017;114: 2075-2084. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  19. Effect of saturated and unsaturated fatty acid supplementation on bio-plastic production under submerged fermentation.

    PubMed

    Srivastava, S K; Tripathi, Abhishek Dutt

    2013-10-01

    Polyhydroxyalkanoates (PHAs) are intracellular reserve material stored by gram-negative bacteria under nutrient-limited condition. PHAs are utilized in biodegradable plastics (bio-plastics) synthesis due to their similarity with conventional synthetic plastic. In the present study, the effect of addition of saturated and unsaturated fatty acids (palmitic acid, stearic acid, oleic acid and linoleic acid) on the production of PHAs by the soil bacterium Alcaligenes sp. NCIM 5085 was studied. Fatty acid supplementation in basal media produced saturated and unsaturated PHAs of medium and short chain length. Gas chromatography analysis of palmitic acid-supplemented media showed the presence of short chain length (scl) PHAs which could potentially serve as precursors for bio-plastic production. The scl PHA was subsequently characterized as PHB by NMR and FTIR. On the other hand, oleic acid and linoleic acid addition showed both saturated and unsaturated PHAs of different chain lengths. Palmitic acid showed maximum PHB content of 70.8 % at concentration of 15 g l -1 under shake flask cultivation. When shake flask cultivation was scaled up in a 7.5-l bioreactor (working volume 3 l), 7.6 g l -1 PHA was produced with a PHB yield (Y P/X ) and productivity of 75.89 % and 0.14 g l -1  h, respectively.

  20. 40 CFR 721.4385 - Hydrofluoric acid, reaction products with heptane.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Hydrofluoric acid, reaction products... Specific Chemical Substances § 721.4385 Hydrofluoric acid, reaction products with heptane. (a) Chemical... hydrofluoric acid, reaction products with heptane (PMN P-98-1036; CAS No. 207409-71-0) is subject to reporting...

  1. 40 CFR 721.4385 - Hydrofluoric acid, reaction products with heptane.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Hydrofluoric acid, reaction products... Specific Chemical Substances § 721.4385 Hydrofluoric acid, reaction products with heptane. (a) Chemical... hydrofluoric acid, reaction products with heptane (PMN P-98-1036; CAS No. 207409-71-0) is subject to reporting...

  2. [Hydrocyanic acid content in cerals and cereal products].

    PubMed

    Lehmann, G; Zinsmeister, H D; Erb, N; Neunhoeffer, O

    1979-03-01

    In the above paper for the first time a systematic study of the amount of hydrocyanic acid in grains and cereal products is reported. Among 24 analysed wheat, rye, maize and oats types, the presence of hydrocyanic acid could be identified in 19 cases in their Karyopses. Similar is the result with 28 among 31 analysed cereal products. The content of hydrocyanic acid lies between 0.1 and 45 microgram/100 gr dried mass.

  3. Impact of climate change on maize potential productivity and the potential productivity gap in southwest China

    NASA Astrophysics Data System (ADS)

    He, Di; Wang, Jing; Dai, Tong; Feng, Liping; Zhang, Jianping; Pan, Xuebiao; Pan, Zhihua

    2014-12-01

    The impact of climate change on maize potential productivity and the potential productivity gap in Southwest China (SWC) are investigated in this paper. We analyze the impact of climate change on the photosynthetic, light-temperature, and climatic potential productivity of maize and their gaps in SWC, by using a crop growth dynamics statistical method. During the maize growing season from 1961 to 2010, minimum temperature increased by 0.20°C per decade ( p < 0.01) across SWC. The largest increases in average and minimum temperatures were observed mostly in areas of Yunnan Province. Growing season average sunshine hours decreased by 0.2 h day-1 per decade ( p < 0.01) and total precipitation showed an insignificant decreasing trend across SWC. Photosynthetic potential productivity decreased by 298 kg ha-1 per decade ( p < 0.05). Both light-temperature and climatic potential productivity decreased ( p < 0.05) in the northeast of SWC, whereas they increased ( p < 0.05) in the southwest of SWC. The gap between light-temperature and climatic potential productivity varied from 12 to 2729 kg ha-1, with the high value areas centered in northern and southwestern SWC. Climatic productivity of these areas reached only 10%-24% of the light-temperature potential productivity, suggesting that there is great potential to increase the maize potential yield by improving water management in these areas. In particular, the gap has become larger in the most recent 10 years. Sensitivity analysis shows that the climatic potential productivity of maize is most sensitive to changes in temperature in SWC. The findings of this study are helpful for quantification of irrigation water requirements so as to achieve maximum yield potentials in SWC.

  4. Optimum production and characterization of an acid protease from marine yeast Metschnikowia reukaufii W6b

    NASA Astrophysics Data System (ADS)

    Li, Jing; Peng, Ying; Wang, Xianghong; Chi, Zhenming

    2010-12-01

    The marine yeast strain W6b isolated from sediment of the South China Sea was found to produce a cell-bound acid protease. The crude acid protease produced by this marine yeast showed the highest activity at pH 3.5 and 40 °C. The optimal pH and temperature for the crude acid protease were in agreement with those for acid protease produced by the terrestrial yeasts. The optimal medium of the acid protease production was seawater containing 1.0% glucose, 1.5% casein, and 0.5% yeast extract, and the optimal cultivation conditions of the acid protease production were pH 4.0, a temperature of 25 °C and a shaking speed of 140 rmin-1. Under the optimal conditions, 72.5 UmL-1 of acid protease activity could be obtained in cell suspension within 48 h of fermentation at shake flask level. The acid protease production was induced by high-molecular-weight nitrogen sources and repressed by low-molecular-weight nitrogen sources. Skimmed-milk-clotting test showed that the crude acid protease from the cell suspension of the yeast W6b had high skimmed milk coagulability. The acid protease produced by M. reukaufii W6b may have highly potential applications in cheese, food and fermentation industries.

  5. Continuous Succinic Acid Production by Actinobacillus succinogenes on Xylose-Enriched Hydrolysate

    DOE PAGES

    Bradfield, Michael F. A.; Mohagheghi, Ali; Salvachua, Davinia; ...

    2015-11-14

    Bio-manufacturing of high-value chemicals in parallel to renewable biofuels has the potential to dramatically improve the overall economic landscape of integrated lignocellulosic biorefineries. However, this will require the generation of carbohydrate streams from lignocellulose in a form suitable for efficient microbial conversion and downstream processing appropriate to the desired end use, making overall process development, along with selection of appropriate target molecules, crucial to the integrated biorefinery. Succinic acid (SA), a high-value target molecule, can be biologically produced from sugars and has the potential to serve as a platform chemical for various chemical and polymer applications. However, the feasibility ofmore » microbial SA production at industrially relevant productivities and yields from lignocellulosic biorefinery streams has not yet been reported.« less

  6. Photoautotrophic production of D-lactic acid in an engineered cyanobacterium

    PubMed Central

    2013-01-01

    Background The world faces the challenge to develop sustainable technologies to replace thousands of products that have been generated from fossil fuels. Microbial cell factories serve as promising alternatives for the production of diverse commodity chemicals and biofuels from renewable resources. For example, polylactic acid (PLA) with its biodegradable properties is a sustainable, environmentally friendly alternative to polyethylene. At present, PLA microbial production is mainly dependent on food crops such as corn and sugarcane. Moreover, optically pure isomers of lactic acid are required for the production of PLA, where D-lactic acid controls the thermochemical and physical properties of PLA. Henceforth, production of D-lactic acid through a more sustainable source (CO2) is desirable. Results We have performed metabolic engineering on Synechocystis sp. PCC 6803 for the phototrophic synthesis of optically pure D-lactic acid from CO2. Synthesis of optically pure D-lactic acid was achieved by utilizing a recently discovered enzyme (i.e., a mutated glycerol dehydrogenase, GlyDH*). Significant improvements in D-lactic acid synthesis were achieved through codon optimization and by balancing the cofactor (NADH) availability through the heterologous expression of a soluble transhydrogenase. We have also discovered that addition of acetate to the cultures improved lactic acid production. More interestingly, 13C-pathway analysis revealed that acetate was not used for the synthesis of lactic acid, but was mainly used for synthesis of certain biomass building blocks (such as leucine and glutamate). Finally, the optimal strain was able to accumulate 1.14 g/L (photoautotrophic condition) and 2.17 g/L (phototrophic condition with acetate) of D-lactate in 24 days. Conclusions We have demonstrated the photoautotrophic production of D-lactic acid by engineering a cyanobacterium Synechocystis 6803. The engineered strain shows an excellent D-lactic acid productivity from CO2. In

  7. Photoautotrophic production of D-lactic acid in an engineered cyanobacterium.

    PubMed

    Varman, Arul M; Yu, Yi; You, Le; Tang, Yinjie J

    2013-11-25

    The world faces the challenge to develop sustainable technologies to replace thousands of products that have been generated from fossil fuels. Microbial cell factories serve as promising alternatives for the production of diverse commodity chemicals and biofuels from renewable resources. For example, polylactic acid (PLA) with its biodegradable properties is a sustainable, environmentally friendly alternative to polyethylene. At present, PLA microbial production is mainly dependent on food crops such as corn and sugarcane. Moreover, optically pure isomers of lactic acid are required for the production of PLA, where D-lactic acid controls the thermochemical and physical properties of PLA. Henceforth, production of D-lactic acid through a more sustainable source (CO2) is desirable. We have performed metabolic engineering on Synechocystis sp. PCC 6803 for the phototrophic synthesis of optically pure D-lactic acid from CO2. Synthesis of optically pure D-lactic acid was achieved by utilizing a recently discovered enzyme (i.e., a mutated glycerol dehydrogenase, GlyDH*). Significant improvements in D-lactic acid synthesis were achieved through codon optimization and by balancing the cofactor (NADH) availability through the heterologous expression of a soluble transhydrogenase. We have also discovered that addition of acetate to the cultures improved lactic acid production. More interestingly, (13)C-pathway analysis revealed that acetate was not used for the synthesis of lactic acid, but was mainly used for synthesis of certain biomass building blocks (such as leucine and glutamate). Finally, the optimal strain was able to accumulate 1.14 g/L (photoautotrophic condition) and 2.17 g/L (phototrophic condition with acetate) of D-lactate in 24 days. We have demonstrated the photoautotrophic production of D-lactic acid by engineering a cyanobacterium Synechocystis 6803. The engineered strain shows an excellent D-lactic acid productivity from CO2. In the late growth phase, the

  8. Development of an industrializable fermentation process for propionic acid production.

    PubMed

    Stowers, Chris C; Cox, Brad M; Rodriguez, Brandon A

    2014-05-01

    Propionic acid (PA) is a short-chain fatty acid with wide industrial application including uses in pharmaceuticals, herbicides, cosmetics, and food preservatives. As a three-carbon building block, PA also has potential as a precursor for high-volume commodity chemicals such as propylene. Currently, most PA is manufactured through petrochemical routes, which can be tied to increasing prices and volatility due to difficulty in demand forecasting and feedstock availability. Herein described are research advancements to develop an industrially feasible, renewable route to PA. Seventeen Propionibacterium strains were screened using glucose and sucrose as the carbon source to identify the best platform strain. Propionibacterium acidipropionici ATCC 4875 was selected as the platform strain and subsequent fermentation optimization studies were performed to maximize productivity and yield. Fermentation productivity was improved three-fold to exceed 2 g/l/h by densifying the inoculum source. Byproduct levels, particularly lactic and succinic acid, were reduced by optimizing fermentor headspace pressure and shear. Following achievement of commercially viable productivities, the lab-grade medium components were replaced with industrial counterparts to further reduce fermentation costs. A pure enzymatically treated corn mash (ECM) medium improved the apparent PA yield to 0.6 g/g (PA produced/glucose consumed), but it came at the cost of reduced productivity. Supplementation of ECM with cyanocobalamin restored productivity to near lab-grade media levels. The optimized ECM recipe achieved a productivity of 0.5 g/l/h with an apparent PA yield of 0.60 g/g corresponding to a media cost <1 USD/kg of PA. These improvements significantly narrow the gap between the fermentation and incumbent petrochemical processes, which is estimated to have a manufacturing cost of 0.82 USD/kg in 2017.

  9. Amino Acid Degradations Produced by Lipid Oxidation Products.

    PubMed

    Hidalgo, Francisco J; Zamora, Rosario

    2016-06-10

    Differently to amino acid degradations produced by carbohydrate-derived reactive carbonyls, amino acid degradations produced by lipid oxidation products are lesser known in spite of being lipid oxidation a major source of reactive carbonyls in food. This article analyzes the conversion of amino acids into Strecker aldehydes, α-keto acids, and amines produced by lipid-derived free radicals and carbonyl compounds, as well as the role of lipid oxidation products on the reactions suffered by these compounds: the formation of Strecker aldehydes and other aldehydes from α-keto acids; the formation of Strecker aldehydes and olefins from amines; the formation of shorter aldehydes from Strecker aldehydes; and the addition reactions suffered by the olefins produced from the amines. The relationships among all these reactions and the effect of reaction conditions on them are discussed. This knowledge should contribute to better control food processing in order to favor the formation of desirable beneficial compounds and to inhibit the production of compounds with deleterious properties.

  10. Genome-scale model guided design of Propionibacterium for enhanced propionic acid production.

    PubMed

    Navone, Laura; McCubbin, Tim; Gonzalez-Garcia, Ricardo A; Nielsen, Lars K; Marcellin, Esteban

    2018-06-01

    Production of propionic acid by fermentation of propionibacteria has gained increasing attention in the past few years. However, biomanufacturing of propionic acid cannot compete with the current oxo-petrochemical synthesis process due to its well-established infrastructure, low oil prices and the high downstream purification costs of microbial production. Strain improvement to increase propionic acid yield is the best alternative to reduce downstream purification costs. The recent generation of genome-scale models for a number of Propionibacterium species facilitates the rational design of metabolic engineering strategies and provides a new opportunity to explore the metabolic potential of the Wood-Werkman cycle. Previous strategies for strain improvement have individually targeted acid tolerance, rate of propionate production or minimisation of by-products. Here we used the P. freudenreichii subsp . shermanii and the pan- Propionibacterium genome-scale metabolic models (GEMs) to simultaneously target these combined issues. This was achieved by focussing on strategies which yield higher energies and directly suppress acetate formation. Using P. freudenreichii subsp . shermanii , two strategies were assessed. The first tested the ability to manipulate the redox balance to favour propionate production by over-expressing the first two enzymes of the pentose-phosphate pathway (PPP), Zwf (glucose-6-phosphate 1-dehydrogenase) and Pgl (6-phosphogluconolactonase). Results showed a 4-fold increase in propionate to acetate ratio during the exponential growth phase. Secondly, the ability to enhance the energy yield from propionate production by over-expressing an ATP-dependent phosphoenolpyruvate carboxykinase (PEPCK) and sodium-pumping methylmalonyl-CoA decarboxylase (MMD) was tested, which extended the exponential growth phase. Together, these strategies demonstrate that in silico design strategies are predictive and can be used to reduce by-product formation in

  11. By-products of electrochemical synthesis of suberic acid

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

    Shirobokova, O.I.; Adamov, A.A.; Freidlin, G.N.

    By-products of the electrochemical synthesis of dimethyl suberate from glutaric anhydride were studied. This is isolated by thermal dehydration of a mixture of lower dicarboxylic acids that are wastes from the production of adipic acid. To isolate the by-products, they used the methods of vacuum rectification and preparative gas-liquid chromatography, and for their identification, PMR, IR spectroscopy, gas-liquid chromatography, and other known physicochemical methods of investigation.

  12. Production of Putative Diterpene Carboxylic Acid Intermediates of Triptolide in Yeast

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

    Forman, Victor; Callari, Roberta; Folly, Christophe

    The development of medical applications exploiting the broad bioactivities of the diterpene therapeutic triptolide from Tripterygium wilfordii is limited by low extraction yields from the native plant. Furthermore, the extraordinarily high structural complexity prevents an economically attractive enantioselective total synthesis. An alternative production route of triptolide through engineered Saccharomyces cerevisiae (yeast) could provide a sustainable source of triptolide. A potential intermediate in the unknown biosynthetic route to triptolide is the diterpene dehydroabietic acid. Here, we report a biosynthetic route to dehydroabietic acid by transient expression of enzymes from T. wilfordii and Sitka spruce (Picea sitchensis) in Nicotiana benthamiana. The combinationmore » of diterpene synthases TwTPS9, TwTPS27, and cytochromes P450 PsCYP720B4 yielded dehydroabietic acid and a novel analog, tentatively identified as ‘miltiradienic acid’. This biosynthetic pathway was reassembled in a yeast strain engineered for increased yields of the pathway intermediates, the diterpene olefins miltiradiene and dehydroabietadiene. Introduction in that strain of PsCYP720B4 in combination with two alternative NADPH-dependent cytochrome P450 reductases resulted in scalable in vivo production of dehydroabietic acid and its analog from glucose. Approaching future elucidation of the remaining biosynthetic steps to triptolide, our findings may provide an independent platform for testing of additional recombinant candidate genes, and ultimately pave the way to biotechnological production of the high value diterpenoid therapeutic.« less

  13. Production of Putative Diterpene Carboxylic Acid Intermediates of Triptolide in Yeast

    DOE PAGES

    Forman, Victor; Callari, Roberta; Folly, Christophe; ...

    2017-06-13

    The development of medical applications exploiting the broad bioactivities of the diterpene therapeutic triptolide from Tripterygium wilfordii is limited by low extraction yields from the native plant. Furthermore, the extraordinarily high structural complexity prevents an economically attractive enantioselective total synthesis. An alternative production route of triptolide through engineered Saccharomyces cerevisiae (yeast) could provide a sustainable source of triptolide. A potential intermediate in the unknown biosynthetic route to triptolide is the diterpene dehydroabietic acid. Here, we report a biosynthetic route to dehydroabietic acid by transient expression of enzymes from T. wilfordii and Sitka spruce (Picea sitchensis) in Nicotiana benthamiana. The combinationmore » of diterpene synthases TwTPS9, TwTPS27, and cytochromes P450 PsCYP720B4 yielded dehydroabietic acid and a novel analog, tentatively identified as ‘miltiradienic acid’. This biosynthetic pathway was reassembled in a yeast strain engineered for increased yields of the pathway intermediates, the diterpene olefins miltiradiene and dehydroabietadiene. Introduction in that strain of PsCYP720B4 in combination with two alternative NADPH-dependent cytochrome P450 reductases resulted in scalable in vivo production of dehydroabietic acid and its analog from glucose. Approaching future elucidation of the remaining biosynthetic steps to triptolide, our findings may provide an independent platform for testing of additional recombinant candidate genes, and ultimately pave the way to biotechnological production of the high value diterpenoid therapeutic.« less

  14. Membrane engineering via trans unsaturated fatty acids production improves Escherichia coli robustness and production of biorenewables.

    PubMed

    Tan, Zaigao; Yoon, Jong Moon; Nielsen, David R; Shanks, Jacqueline V; Jarboe, Laura R

    2016-05-01

    Constructing microbial biocatalysts that produce biorenewables at economically viable yields and titers is often hampered by product toxicity. For production of short chain fatty acids, membrane damage is considered the primary mechanism of toxicity, particularly in regards to membrane integrity. Previous engineering efforts in Escherichia coli to increase membrane integrity, with the goal of increasing fatty acid tolerance and production, have had mixed results. Herein, a novel approach was used to reconstruct the E. coli membrane by enabling production of a novel membrane component. Specifically, trans unsaturated fatty acids (TUFA) were produced and incorporated into the membrane of E. coli MG1655 by expression of cis-trans isomerase (Cti) from Pseudomonas aeruginosa. While the engineered strain was found to have no increase in membrane integrity, a significant decrease in membrane fluidity was observed, meaning that membrane polarization and rigidity were increased by TUFA incorporation. As a result, tolerance to exogenously added octanoic acid and production of octanoic acid were both increased relative to the wild-type strain. This membrane engineering strategy to improve octanoic acid tolerance was found to require fine-tuning of TUFA abundance. Besides improving tolerance and production of carboxylic acids, TUFA production also enabled increased tolerance in E. coli to other bio-products, e.g. alcohols, organic acids, aromatic compounds, a variety of adverse industrial conditions, e.g. low pH, high temperature, and also elevated styrene production, another versatile bio-chemical product. TUFA permitted enhanced growth due to alleviation of bio-product toxicity, demonstrating the general effectiveness of this membrane engineering strategy towards improving strain robustness. Copyright © 2016 International Metabolic Engineering Society. Published by Elsevier Inc. All rights reserved.

  15. Butyric acid production from softwood hydrolysate by acetate-consuming Clostridium sp. S1 with high butyric acid yield and selectivity.

    PubMed

    Kim, Minsun; Kim, Ki-Yeon; Lee, Kyung Min; Youn, Sung Hun; Lee, Sun-Mi; Woo, Han Min; Oh, Min-Kyu; Um, Youngsoon

    2016-10-01

    The aim of this work was to study the butyric acid production from softwood hydrolysate by acetate-consuming Clostridium sp. S1. Results showed that Clostridium sp. S1 produced butyric acid by simultaneously utilizing glucose and mannose in softwood hydrolysate and, more remarkably, it consumed acetic acid in hydrolysate. Clostridium sp. S1 utilized each of glucose, mannose, and xylose as well as mixed sugars simultaneously with partially repressed xylose utilization. When softwood (Japanese larch) hydrolysate containing glucose and mannose as the main sugars was used, Clostridium sp. S1 produced 21.17g/L butyric acid with the yield of 0.47g/g sugar and the selectivity of 1 (g butyric acid/g total acids) owing to the consumption of acetic acid in hydrolysate. The results demonstrate potential of Clostridium sp. S1 to produce butyric acid selectively and effectively from hydrolysate not only by utilizing mixed sugars simultaneously but also by converting acetic acid to butyric acid. Copyright © 2016 Elsevier Ltd. All rights reserved.

  16. Vinegar production from post-distillation slurry deriving from rice shochu production with the addition of caproic acid-producing bacteria consortium and lactic acid bacterium.

    PubMed

    Yuan, Hua-Wei; Tan, Li; Chen, Hao; Sun, Zhao-Yong; Tang, Yue-Qin; Kida, Kenji

    2017-12-01

    To establish a zero emission process, the post-distillation slurry of a new type of rice shochu (NTRS) was used for the production of health promoting vinegar. Since the NTRS post-distillation slurry contained caproic acid and lactic acid, the effect of these two organic acids on acetic acid fermentation was first evaluated. Based on these results, Acetobacter aceti CICC 21684 was selected as a suitable strain for subsequent production of vinegar. At the laboratory scale, acetic acid fermentation of the NTRS post-distillation slurry in batch mode resulted in an acetic acid concentration of 41.9 g/L, with an initial ethanol concentration of 40 g/L, and the acetic acid concentration was improved to 44.5 g/L in fed-batch mode. Compared to the NTRS post-distillation slurry, the vinegar product had higher concentrations of free amino acids and inhibition of angiotensin I converting enzyme activity. By controlling the volumetric oxygen transfer coefficient to be similar to that of the laboratory scale production, 45 g/L of acetic acid was obtained at the pilot scale, using a 75-L fermentor with a working volume of 40 L, indicating that vinegar production can be successfully scaled up. Copyright © 2017 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  17. Formation of Amino Acid Thioesters for Prebiotic Peptide Synthesis: Catalysis By Amino Acid Products

    NASA Technical Reports Server (NTRS)

    Weber, Arthur L.; DeVincenzi, Donald L. (Technical Monitor)

    1999-01-01

    The origin of life can be described as a series of events in which a prebiotic chemical process came increasingly under the control of its catalytic products. In our search for this prebiotic process that yielded catalytic takeover products (such as polypeptides), we have been investigating a reaction system that generates peptide-forming amino acid thioesters from formaldehyde, glycolaldehyde, and ammonia in the presence of thiols. As shown below, this model process begins by aldol condensation of formaldehyde and glycolaldehyde to give trioses and releases. These sugars then undergo beta-dehydration yielding their respective alpha-ketoaldehydes. Addition of ammonia to the alpha-ketoaldehydes yields imines which can either: (a) rearrange in the presence of thesis to give amino acid thioesters or (be react with another molecule of aldehyde to give imidazoles. This 'one-pot' reaction system operates under mild aqueous conditions, and like modem amino acid biosynthesis, uses sugar intermediates which are converted to products by energy-yielding redox reactions. Recently, we discovered that amino acids, such as the alanine reaction product, catalyze the first and second steps of the process. In the presence of ammonia the process also generates other synthetically useful products, like the important biochemical -- pyruvic acid.

  18. A mutation of Aspergillus niger for hyper-production of citric acid from corn meal hydrolysate in a bioreactor.

    PubMed

    Hu, Wei; Liu, Jing; Chen, Ji-hong; Wang, Shu-yang; Lu, Dong; Wu, Qing-hua; Li, Wen-jian

    2014-11-01

    The properties of the screened mutants for hyper-production of citric acid induced by carbon ((12)C(6+)) ion beams and X-ray irradiation were investigated in our current study. Among these mutants, mutant H4002 screened from (12)C(6+) ion irradiation had a higher yield of citric acid production than the parental strain in a 250-ml shaking flash. These expanded submerged experiments in a bioreactor were also carried out for mutant H4002. The results showed that (177.7-196.0) g/L citric acid was accumulated by H4002 through exploiting corn meal hydrolysate (containing initial 200.0-235.7 g/L sugar) with the productivity of (2.96-3.27) g/(L∙h). This was especially true when the initial sugar concentration was 210 g/L, and the best economical citric acid production reached (187.5±0.7) g/L with a productivity of 3.13 g/(L∙h). It was observed that mutant H4002 can utilize low-cost corn meal as a feedstock to efficiently produce citric acid. These results imply that the H4002 strain has the industrial production potentiality for citric acid and offers strong competition for the citric acid industry.

  19. A mutation of Aspergillus niger for hyper-production of citric acid from corn meal hydrolysate in a bioreactor*

    PubMed Central

    Hu, Wei; Liu, Jing; Chen, Ji-hong; Wang, Shu-yang; Lu, Dong; Wu, Qing-hua; Li, Wen-jian

    2014-01-01

    The properties of the screened mutants for hyper-production of citric acid induced by carbon (12C6+) ion beams and X-ray irradiation were investigated in our current study. Among these mutants, mutant H4002 screened from 12C6+ ion irradiation had a higher yield of citric acid production than the parental strain in a 250-ml shaking flash. These expanded submerged experiments in a bioreactor were also carried out for mutant H4002. The results showed that (177.7–196.0) g/L citric acid was accumulated by H4002 through exploiting corn meal hydrolysate (containing initial 200.0–235.7 g/L sugar) with the productivity of (2.96–3.27) g/(L∙h). This was especially true when the initial sugar concentration was 210 g/L, and the best economical citric acid production reached (187.5±0.7) g/L with a productivity of 3.13 g/(L∙h). It was observed that mutant H4002 can utilize low-cost corn meal as a feedstock to efficiently produce citric acid. These results imply that the H4002 strain has the industrial production potentiality for citric acid and offers strong competition for the citric acid industry. PMID:25367793

  20. Polyhydroxyalkanoate production potential of heterotrophic bacteria in activated sludge.

    PubMed

    Inoue, Daisuke; Suzuki, Yuta; Uchida, Takahiro; Morohoshi, Jota; Sei, Kazunari

    2016-01-01

    This study was conducted to evaluate the polyhydroxyalkanoate (PHA) production potential of cultivable heterotrophic bacteria in activated sludge by genotypic and phenotypic characterizations. A total of 114 bacterial strains were isolated from four activated sludge samples taken from a lab-scale sequencing batch reactor and three wastewater treatment processes of two municipal wastewater treatment plants. PCR detection of the phaC genes encoding class I and II PHA synthase revealed that 15% of the total isolates possessed phaC genes, all of which had the closest similarities to known phaC genes of α- and β-Proteobacteria and Actinobacteria. PHA production experiments under aerobic and nitrogen-limited conditions showed that 68% of the total isolates were capable of producing PHA from at least one of the six substrates used (acetate, propionate, lactate, butyrate, glucose and glycerol). Genotypic and phenotypic characterizations revealed that 75% of the activated sludge bacteria had PHA production potential. Our results also indicated that short-chain fatty acids would be the preferable substrates for PHA production by activated sludge bacteria, and that there might be a variety of unidentified phaC genes in activated sludge. Copyright © 2015 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  1. Mycosporine-Like Amino Acids: Potential Health and Beauty Ingredients

    PubMed Central

    Chrapusta, Ewelina; Kaminski, Ariel; Duchnik, Kornelia; Bober, Beata; Adamski, Michal; Bialczyk, Jan

    2017-01-01

    Human skin is constantly exposed to damaging ultraviolet radiation (UVR), which induces a number of acute and chronic disorders. To reduce the risk of UV-induced skin injury, people apply an additional external protection in the form of cosmetic products containing sunscreens. Nowadays, because of the use of some chemical filters raises a lot of controversies, research focuses on exploring novel, fully safe and highly efficient natural UV-absorbing compounds that could be used as active ingredients in sun care products. A promising alternative is the application of multifunctional mycosporine-like amino acids (MAAs), which can effectively compete with commercially available filters. Here, we outline a complete characterization of these compounds and discuss their enormous biotechnological potential with special emphasis on their use as sunscreens, activators of cells proliferation, anti-cancer agents, anti-photoaging molecules, stimulators of skin renewal, and functional ingredients of UV-protective biomaterials. PMID:29065484

  2. Effects of 20 standard amino acids on the growth, total fatty acids production, and γ-linolenic acid yield in Mucor circinelloides.

    PubMed

    Tang, Xin; Zhang, Huaiyuan; Chen, Haiqin; Chen, Yong Q; Chen, Wei; Song, Yuanda

    2014-12-01

    Twenty standard amino acids were examined as single nitrogen source on the growth, total fatty acids production, and yield of γ-linolenic acid (GLA) in Mucor circinelloides. Of the amino acids, tyrosine gave the highest biomass and lipid accumulation and thus resulted in a high GLA yield with respective values of 17.8 g/L, 23 % (w/w, dry cell weight, DCW), and 0.81 g/L, which were 36, 25, and 72 % higher than when the fungus was grown with ammonium tartrate. To find out the potential mechanism underlying the increased lipid accumulation of M. circinelloides when grown on tyrosine, the activity of lipogenic enzymes of the fungus during lipid accumulation phase was measured. The enzyme activities of glucose 6-phosphate dehydrogenase, 6-phosphogluconate dehydrogenase, and ATP-citrate lyase were up-regulated, while NADP-isocitrate dehydrogenase was down-regulated by tyrosine during the lipid accumulation phase of the fungus which suggested that these enzymes may be involved in the increased lipid biosynthesis by tyrosine in this fungus.

  3. Screening of new British thraustochytrids isolates for docosahexaenoic acid (DHA) production.

    PubMed

    Marchan, Loris Fossier; Lee Chang, Kim J; Nichols, Peter D; Polglase, Jane L; Mitchell, Wilfrid J; Gutierrez, Tony

    2017-01-01

    Thraustochytrids isolated from hot tropical and sub-tropical waters have been well studied for DHA and biodiesel production in the last decades. However, little research has been performed on the oils of cold water thraustochytrids, in particular from the North Sea region. In this study, thraustochytrid strains from British waters showed high relative levels of omega-3 long-chain (≥C 20 ) polyunsaturated fatty acids (LC-PUFA), including docosahexaenoic acid (DHA, 22:6ω3). The relative levels of DHA (as % of total fatty acids, TFA) in the different British strains are hitherto amongst the highest recorded from any thraustochytrid screening study, with strain TL18 reaching up to 67% DHA in modified Glucose-Yeast Extract-Peptone (GYP) medium. At this screening stage, low final biomass and fatty acid yield were observed in modified GYP and MarChiquita-Brain Heart Broth (MCBHB), while PUFA profiles (as % of PUFA) remained unaltered regardless of the culture medium used. Hence, optimizing the medium and culture conditions to improve growth and lipid content, without impacting the relative percentage of DHA, has the potential to increase the final DHA concentration. With this in mind, three strains were identified as promising organisms for the production of DHA. In the context of possible future industrial exploitation involving a winterization step, we investigated the recycling of the residual oil for biodiesel use. To do this, a mathematical model was used to assess the intrinsic properties of the by-product oil. The results showed the feasibility of producing primary DHA-rich oil, assuming optimized conditions, while using the by-product oil for biodiesel use.

  4. Microalgal biofactories: a promising approach towards sustainable omega-3 fatty acid production

    PubMed Central

    2012-01-01

    Omega-3 fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) provide significant health benefits and this has led to an increased consumption as dietary supplements. Omega-3 fatty acids EPA and DHA are found in animals, transgenic plants, fungi and many microorganisms but are typically extracted from fatty fish, putting additional pressures on global fish stocks. As primary producers, many marine microalgae are rich in EPA (C20:5) and DHA (C22:6) and present a promising source of omega-3 fatty acids. Several heterotrophic microalgae have been used as biofactories for omega-3 fatty acids commercially, but a strong interest in autotrophic microalgae has emerged in recent years as microalgae are being developed as biofuel crops. This paper provides an overview of microalgal biotechnology and production platforms for the development of omega-3 fatty acids EPA and DHA. It refers to implications in current biotechnological uses of microalgae as aquaculture feed and future biofuel crops and explores potential applications of metabolic engineering and selective breeding to accumulate large amounts of omega-3 fatty acids in autotrophic microalgae. PMID:22830315

  5. Fluoride-sensitivity of growth and acid production of oral Actinomyces: comparison with oral Streptococcus.

    PubMed

    Kawashima, Junko; Nakajo, Kazuko; Washio, Jumpei; Mayanagi, Gen; Shimauchi, Hidetoshi; Takahashi, Nobuhiro

    2013-12-01

    Actinomyces are predominant oral bacteria; however, their cariogenic potential in terms of acid production and fluoride sensitivity has not been elucidated in detail and compared with that of other caries-associated oral bacteria, such as Streptococcus. Therefore, this study aimed to elucidate and compare the acid production and growth of Actinomyces and Streptococcus in the presence of bicarbonate and fluoride to mimic conditions in the oral cavity. Acid production from glucose was measured by pH-stat at pH 5.5 and 7.0 under anaerobic conditions. Growth rate was assessed by optical density in anaerobic culture. Although Actinomyces produced acid at a lower rate than did Streptococcus, their acid production was more tolerant of fluoride (IDacid production 50 = 110-170 ppm at pH 7.0 and 10-13 ppm at pH 5.5) than that of Streptococcus (IDacid production 50 = 36-53 ppm at pH 7.0 and 6.3-6.5 ppm at pH 5.5). Bicarbonate increased acid production by Actinomyces with prominent succinate production and enhanced their fluoride tolerance (IDacid production 50 = 220-320 ppm at pH 7.0 and 33-52 ppm at pH 5.5). Bicarbonate had no effect on these variables in Streptococcus. In addition, although the growth rate of Actinomyces was lower than that of Streptococcus, Actinomyces growth was more tolerant of fluoride (IDgrowth 50 = 130-160 ppm) than was that of Streptococcus (IDgrowth 50 = 27-36 ppm). These results indicate that oral Actinomyces are more tolerant of fluoride than oral Streptococcus, and bicarbonate enhances the fluoride tolerance of oral Actinomyces. Because of the limited number of species tested here, further study is needed to generalize these findings to the genus level. © 2013 The Societies and Wiley Publishing Asia Pty Ltd.

  6. Method for production of petroselinic acid and OMEGA12 hexadecanoic acid in transgenic plants

    DOEpatents

    Ohlrogge, John B.; Cahoon, Edgar B.; Shanklin, John; Somerville, Christopher R.

    1995-01-01

    The present invention relates to a process for producing lipids containing the fatty acid petroselinic acid in plants. The production of petroselinic acid is accomplished by genetically transforming plants which do not normally accumulate petroselinic acid with a gene for a .omega.12 desaturase from another species which does normally accumulate petroselinic acid.

  7. [Dependence of rumen fatty acid production on the composition of rations].

    PubMed

    Lebzien, P; Rohr, K; Oslage, H J

    1981-10-01

    In three experiments with two Black-and-White dairy cows the influence of soybean oil and coconut fat as well as that of rations rich in roughage and concentrated feed on the production of fatty acids were determined with the isotope dilution method. A change in the method of sampling from the rumen in the course of the investigations resulted in distinctly different absolute production quotas, which can presumably be traced back to the disproportionate mixing in of the isotope and/or different production quotas in various regions of the rumen. The relative differences between the production quotas dependent on the rations, however were approximately the same with both sampling methods, so that they make the comparison of the rations concerning rumen fermentation possible. The production of acetic acid and the total production of fatty acids (C2--C4) correlated closely both with the intake of digestible energy and the intake of digestible organic matter. There was also a highly significant correlation o that they make the comparison of the rations concerning rumen fermentation possible. The production of acetic acid and the total production of fatty acids (C2--C4) correlated closely both with the intake of digestible energy and the intake of digestible organic matter. There was also a highly significant correlation o that they make the comparison of the rations concerning rumen fermentation possible. The production of acetic acid and the total production of fatty acids (C2--C4) correlated closely both with the intake of digestible energy and the intake of digestible organic matter. There was also a highly significant correlation between the relation of acetic and propionic acid in the rumen fluid and the quotient from acetic and propionic acid produced. In contrast to this, a significant relation between the concentration of fatty acids and the production of fatty acids could not be ascertained. Soybean oil and coconut fat brought about a slightly better

  8. Lipids and Fatty Acids of Nudibranch Mollusks: Potential Sources of Bioactive Compounds

    PubMed Central

    Zhukova, Natalia V.

    2014-01-01

    The molecular diversity of chemical compounds found in marine animals offers a good chance for the discovery of novel bioactive compounds of unique structures and diverse biological activities. Nudibranch mollusks, which are not protected by a shell and produce chemicals for various ecological uses, including defense against predators, have attracted great interest for their lipid composition. Lipid analysis of eight nudibranch species revealed dominant phospholipids, sterols and monoalkyldiacylglycerols. Among polar lipids, 1-alkenyl-2-acyl glycerophospholipids (plasmalogens) and ceramide-aminoethyl phosphonates were found in the mollusks. The fatty acid compositions of the nudibranchs differed greatly from those of other marine gastropods and exhibited a wide diversity: very long chain fatty acids known as demospongic acids, a series of non-methylene-interrupted fatty acids, including unusual 21:2∆7,13, and an abundance of various odd and branched fatty acids typical of bacteria. Symbiotic bacteria revealed in some species of nudibranchs participate presumably in the production of some compounds serving as a chemical defense for the mollusks. The unique fatty acid composition of the nudibranchs is determined by food supply, inherent biosynthetic activities and intracellular symbiotic microorganisms. The potential of nudibranchs as a source of biologically active lipids and fatty acids is also discussed. PMID:25196731

  9. Withania somnifera attenuates acid production, acid tolerance and extra-cellular polysaccharide formation of Streptococcus mutans biofilms.

    PubMed

    Pandit, Santosh; Song, Kwang-Yeob; Jeon, Jae-Gyu

    2014-01-01

    Withania somnifera (Ashwagandha) is a plant of the Solanaceae family. It has been widely used as a remedy for a variety of ailments in India and Nepal. The plant has also been used as a controlling agent for dental diseases. The aim of the present study was to evaluate the activity of the methanol extract of W. somnifera against the physiological ability of cariogenic biofilms and to identify the components of the extract. To determine the activity of the extract, assays for sucrose-dependent bacterial adherence, glycolytic acid production, acid tolerance, and extracellular polysaccharide formation were performed using Streptococcus mutans biofilms. The viability change of S. mutans biofilms cells was also determined. A phytochemical analysis of the extract was performed using TLC and LC/MS/MS. The extract showed inhibitory effects on sucrose-dependent bacterial adherence (≥ 100 μg/ml), glycolytic acid production (≥ 300 μg/ml), acid tolerance (≥ 300 μg/ml), and extracellular polysaccharide formation (≥ 300 μg/ml) of S. mutans biofilms. However, the extract did not alter the viability of S. mutans biofilms cells in all concentrations tested. Based on the phytochemical analysis, the activity of the extract may be related to the presence of alkaloids, anthrones, coumarines, anthraquinones, terpenoids, flavonoids, and steroid lactones (withanolide A, withaferin A, withanolide B, withanoside IV, and 12-deoxy withastramonolide). These data indicate that W. somnifera may be a potential agent for restraining the physiological ability of cariogenic biofilms.

  10. Succinic acid production with Actinobacillus succinogenes: rate and yield analysis of chemostat and biofilm cultures.

    PubMed

    Brink, Hendrik Gideon; Nicol, Willie

    2014-08-19

    Succinic acid is well established as bio-based platform chemical with production quantities expecting to increase exponentially within the next decade. Actinobacillus succinogenes is by far the most studied wild organism for producing succinic acid and is known for high yield and titre during production on various sugars in batch culture. At low shear conditions continuous fermentation with A. succinogenes results in biofilm formation. In this study, a novel shear controlled fermenter was developed that enabled: 1) chemostat operation where self-immobilisation was opposed by high shear rates and, 2) in-situ removal of biofilm by increasing shear rates and subsequent analysis thereof. The volumetric productivity of the biofilm fermentations were an order of magnitude more than the chemostat runs. In addition the biofilm runs obtained substantially higher yields. Succinic acid to acetic acid ratios for chemostat runs were 1.28±0.2 g.g(-1), while the ratios for biofilm runs started at 2.4 g.g(-1) and increased up to 3.3 g.g(-1) as glucose consumption increased. This corresponded to an overall yield on glucose of 0.48±0.05 g.g(-1) for chemostat runs, while the yields varied between 0.63 g.g(-1) and 0.74 g.g(-1) for biofilm runs. Specific growth rates (μ) were shown to be severely inhibited by the formation of organic acids, with μ only 12% of μ(max) at a succinic acid titre of 7 g.L(-1). Maintenance production of succinic acid was shown to be dominant for the biofilm runs with cell based production rates (extracellular polymeric substance removed) decreasing as SA titre increases. The novel fermenter allowed for an in-depth bioreaction analysis of A. succinogenes. Biofilm cells achieve higher SA yields than suspended cells and allow for operation at higher succinic acid titre. Both growth and maintenance rates were shown to drastically decrease with succinic acid titre. The A. succinogenes biofilm process has vast potential, where self-induced high cell densities

  11. Succinic Acid Production from Cheese Whey using Actinobacillus succinogenes 130 Z

    NASA Astrophysics Data System (ADS)

    Wan, Caixia; Li, Yebo; Shahbazi, Abolghasem; Xiu, Shuangning

    Actinobacillus succinogenes 130 Z was used to produce succinic acid from cheese whey in this study. At the presence of external CO2 supply, the effects of initial cheese whey concentration, pH, and inoculum size on the succinic acid production were studied. The by-product formation during the fermentation process was also analyzed. The highest succinic acid yield of 0.57 was obtained at initial cheese whey concentration of 50 g/L, while the highest succinic acid productivity of 0.58 g h-1 L-1 was obtained at initial cheese whey concentration of 100 g/L. Increase in pH and inoculum size caused higher succinic acid yield and productivity. At the preferred fermentation condition of pH 6.8, inoculum size of 5% and initial cheese whey concentration of 50 g/L, succinic acid yield of 0.57, and productivity of 0.44 g h-1 L-1 were obtained. Acetic acid and formic acid were the main by-products throughout the fermentation run of 48 h. It is feasible to produce succinic acid using lactose from cheese whey as carbon resource by A. succinogenes 130 Z.

  12. Extending shikimate pathway for the production of muconic acid and its precursor salicylic acid in Escherichia coli.

    PubMed

    Lin, Yuheng; Sun, Xinxiao; Yuan, Qipeng; Yan, Yajun

    2014-05-01

    cis,cis-Muconic acid (MA) and salicylic acid (SA) are naturally-occurring organic acids having great commercial value. MA is a potential platform chemical for the manufacture of several widely-used consumer plastics; while SA is mainly used for producing pharmaceuticals (for example, aspirin and lamivudine) and skincare and haircare products. At present, MA and SA are commercially produced by organic chemical synthesis using petro-derived aromatic chemicals, such as benzene, as starting materials, which is not environmentally friendly. Here, we report a novel approach for efficient microbial production of MA via extending shikimate pathway by introducing the hybrid of an SA biosynthetic pathway with its partial degradation pathway. First, we engineered a well-developed phenylalanine producing Escherichia coli strain into an SA overproducer by introducing isochorismate synthase and isochorismate pyruvate lyase. The engineered strain is able to produce 1.2g/L of SA from simple carbon sources, which is the highest titer reported so far. Further, the partial SA degradation pathway involving salicylate 1-monoxygenase and catechol 1,2-dioxygenase is established to achieve the conversion of SA to MA. Finally, a de novo MA biosynthetic pathway is assembled by integrating the established SA biosynthesis and degradation modules. Modular optimization enables the production of up to 1.5g/L MA within 48h in shake flasks. This study not only establishes an efficient microbial platform for the production of SA and MA, but also demonstrates a generalizable pathway design strategy for the de novo biosynthesis of valuable degradation metabolites. Copyright © 2014. Published by Elsevier Inc.

  13. Method for production of petroselinic acid and OMEGA12 hexadecanoic acid in transgenic plants

    DOEpatents

    Ohlrogge, J.B.; Cahoon, E.B.; Shanklin, J.; Somerville, C.R.

    1995-07-04

    The present invention relates to a process for producing lipids containing the fatty acid, petroselinic acid, in plants. The production of petroselinic acid is accomplished by genetically transforming plants which do not normally accumulate petroselinic acid with a gene for a {omega}12 desaturase from another species which does normally accumulate petroselinic acid. 19 figs.

  14. Actinobacillus succinogenes ATCC 55618 Fermentation Medium Optimization for the Production of Succinic Acid by Response Surface Methodology

    PubMed Central

    Zhu, Li-Wen; Wang, Cheng-Cheng; Liu, Rui-Sang; Li, Hong-Mei; Wan, Duan-Ji; Tang, Ya-Jie

    2012-01-01

    As a potential intermediary feedstock, succinic acid takes an important place in bulk chemical productions. For the first time, a method combining Plackett-Burman design (PBD), steepest ascent method (SA), and Box-Behnken design (BBD) was developed to optimize Actinobacillus succinogenes ATCC 55618 fermentation medium. First, glucose, yeast extract, and MgCO3 were identified to be key medium components by PBD. Second, preliminary optimization was run by SA method to access the optimal region of the key medium components. Finally, the responses, that is, the production of succinic acid, were optimized simultaneously by using BBD, and the optimal concentration was located to be 84.6 g L−1 of glucose, 14.5 g L−1 of yeast extract, and 64.7 g L−1 of MgCO3. Verification experiment indicated that the maximal succinic acid production of 52.7 ± 0.8 g L−1 was obtained under the identified optimal conditions. The result agreed with the predicted value well. Compared with that of the basic medium, the production of succinic acid and yield of succinic acid against glucose were enhanced by 67.3% and 111.1%, respectively. The results obtained in this study may be useful for the industrial commercial production of succinic acid. PMID:23093852

  15. End product yields from the extraruminal fermentation of various polysaccharide, protein and nucleic acid components of biofuels feedstocks.

    PubMed

    Weimer, Paul J

    2011-02-01

    "Extraruminal" fermentations employing in vitro incubation of mixed ruminal bacterial consortia, are capable of converting a complex array of biomass materials to mixtures of volatile fatty acids (VFA), methane, and carbon dioxide. Most of the potential energy in the biomass feedstock is retained in the VFA products, which are potential reactants for electrochemical conversion to hydrocarbon fuels. Quantitative data on VFA yields and proportions from biomass components are necessary for determining industrial feasibility, but such measurements have not been systematically reported. VFA yields and proportions were determined for a variety of carbohydrates, proteins and nucleic acids. Carbohydrates yielded primarily acetic and propionic acids, while proteins also yielded a more favorable product mix (longer average chain length and branched chain VFAs). Addition of certain co-substrates (e.g., glycerol) favorably improved the VFA product mix. The results have implications for hydrocarbon fuel generation from biomass materials by hybrid fermentation/chemical processes. Published by Elsevier Ltd.

  16. Chlorogenic acid and maize ear rot resistance: a dynamic study investigating Fusarium graminearum development, deoxynivalenol production, and phenolic acid accumulation.

    PubMed

    Atanasova-Penichon, Vessela; Pons, Sebastien; Pinson-Gadais, Laetitia; Picot, Adeline; Marchegay, Gisèle; Bonnin-Verdal, Marie-Noelle; Ducos, Christine; Barreau, Christian; Roucolle, Joel; Sehabiague, Pierre; Carolo, Pierre; Richard-Forget, Florence

    2012-12-01

    Fusarium graminearum is the causal agent of Gibberella ear rot and produces trichothecene mycotoxins. Basic questions remain unanswered regarding the kernel stages associated with trichothecene biosynthesis and the kernel metabolites potentially involved in the regulation of trichothecene production in planta. In a two-year field study, F. graminearum growth, trichothecene accumulation, and phenolic acid composition were monitored in developing maize kernels of a susceptible and a moderately resistant variety using quantitative polymerase chain reaction and liquid chromatography coupled with photodiode array or mass spectrometry detection. Infection started as early as the blister stage and proceeded slowly until the dough stage. Then, a peak of trichothecene accumulation occurred and infection progressed exponentially until the final harvest time. Both F. graminearum growth and trichothecene production were drastically reduced in the moderately resistant variety. We found that chlorogenic acid is more abundant in the moderately resistant variety, with levels spiking in the earliest kernel stages induced by Fusarium infection. This is the first report that precisely describes the kernel stage associated with the initiation of trichothecene production and provides in planta evidence that chlorogenic acid may play a role in maize resistance to Gibberella ear rot and trichothecene accumulation.

  17. Effect of oxidoreduction potential on aroma biosynthesis by lactic acid bacteria in nonfat yogurt.

    PubMed

    Martin, F; Cachon, R; Pernin, K; De Coninck, J; Gervais, P; Guichard, E; Cayot, N

    2011-02-01

    The aim of this study was to investigate the effect of oxidoreduction potential (Eh) on the biosynthesis of aroma compounds by lactic acid bacteria in non-fat yogurt. The study was done with yogurts fermented by Lactobacillus bulgaricus and Streptococcus thermophilus. The Eh was modified by the application of different gaseous conditions (air, nitrogen, and nitrogen/hydrogen). Acetaldehyde, dimethyl sulfide, diacetyl, and pentane-2,3-dione, as the major endogenous odorant compounds of yogurt, were chosen as tracers for the biosynthesis of aroma compounds by lactic acid bacteria. Oxidative conditions favored the production of acetaldehyde, dimethyl sulfide, and diketones (diacetyl and pentane-2,3-dione). The Eh of the medium influences aroma production in yogurt by modifying the metabolic pathways of Lb. bulgaricus and Strep. thermophilus. The use of Eh as a control parameter during yogurt production could permit the control of aroma formation. Copyright © 2011 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  18. Mechanisms of volatile production from non-sulfur amino acids by irradiation

    NASA Astrophysics Data System (ADS)

    Ahn, Dong Uk; Lee, Eun Joo; Feng, Xi; Zhang, Wangang; Lee, Ji Hwan; Jo, Cheorun; Nam, Kichang

    2016-02-01

    Non-sulfur amino acid monomers were used to study the mechanisms of volatile production in meat by irradiation. Irradiation not only produced many volatiles but also increased the amounts of volatiles from non-sulfur amino acid monomers. The major reaction mechanisms involved in volatile production from each group of the amino acids by irradiation differ significantly. However, we speculate that the radiolysis of amino acid side chains were the major mechanism. In addition, Strecker degradation, especially the production of aldehydes from aliphatic group amino acids, and deamination, isomerization, decarboxylation, cyclic reaction and dehydrogenation of the initial radiolytic products were also contributed to the production of volatile compounds. Each amino acid monomers produced different odor characteristics, but the intensities of odor from all non-sulfur amino acid groups were very weak. This indicated that the contribution of volatiles produced from non-sulfur amino acids was minor. If the volatile compounds from non-sulfur amino acids, especially aldehydes, interact with other volatiles compounds such as sulfur compounds, however, they can contribute to the off-odor of irradiated meat significantly.

  19. Degradation of caffeic acid in subcritical water and online HPLC-DPPH assay of degradation products.

    PubMed

    Khuwijitjaru, Pramote; Suaylam, Boonyanuch; Adachi, Shuji

    2014-02-26

    Caffeic acid was subjected to degradation under subcritical water conditions within 160-240 °C and at a constant pressure of 5 MPa in a continuous tubular reactor. Caffeic acid degraded quickly at these temperatures; the main products identified by liquid chromatography-diode array detection/mass spectrometry were hydroxytyrosol, protocatechuic aldehyde, and 4-vinylcatechol. The reaction rates for the degradation of caffeic acid and the formation of products were evaluated. Online high-performance liquid chromatography/2,2-diphenyl-1-picryhydrazyl assay was used to determine the antioxidant activity of each product in the solution. It was found that the overall antioxidant activity of the treated solution did not change during the degradation process. This study showed a potential of formation of antioxidants from natural phenolic compounds under these subcritical water conditions, and this may lead to a discovering of novel antioxidants compounds during the extraction by this technique.

  20. Propionic acid production from corn stover hydrolysate by Propionibacterium acidipropionici

    DOE PAGES

    Wang, Xiaoqing; Salvachua, Davinia; Sanchez i Nogue, Violeta; ...

    2017-08-17

    The production of value-added chemicals alongside biofuels from lignocellulosic hydrolysates is critical for developing economically viable biorefineries. Here, the production of propionic acid (PA), a potential building block for C3-based chemicals, from corn stover hydrolysate is investigated using the native PA-producing bacterium Propionibacterium acidipropionici. A wide range of culture conditions and process parameters were examined and experimentally optimized to maximize titer, rate, and yield of PA. The effect of gas sparging during fermentation was first examined, and N 2 was found to exhibit improved performance over CO 2. Subsequently, the effects of different hydrolysate concentrations, nitrogen sources, and neutralization agentsmore » were investigated. One of the best combinations found during batch experiments used yeast extract (YE) as the primary nitrogen source and NH 4OH for pH control. This combination enabled PA titers of 30.8 g/L with a productivity of 0.40 g/L h from 76.8 g/L biomass sugars, while successfully minimizing lactic acid production. Due to the economic significance of downstream separations, increasing titers using fed-batch fermentation was examined by changing both feeding media and strategy. Continuous feeding of hydrolysate was found to be superior to pulsed feeding and combined with high YE concentrations increased PA titers to 62.7 g/L and improved the simultaneous utilization of different biomass sugars. Additionally, applying high YE supplementation maintains the lactic acid concentration below 4 g/L for the duration of the fermentation. Finally, with the aim of increasing productivity, high cell density fed-batch fermentations were conducted. PA titers increased to 64.7 g/L with a productivity of 2.35 g/L h for the batch stage and 0.77 g/L h for the overall process. These results highlight the importance of media and fermentation strategy to improve PA production. Altogether, this work demonstrates the feasibility of

  1. Propionic acid production from corn stover hydrolysate by Propionibacterium acidipropionici

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

    Wang, Xiaoqing; Salvachua, Davinia; Sanchez i Nogue, Violeta

    The production of value-added chemicals alongside biofuels from lignocellulosic hydrolysates is critical for developing economically viable biorefineries. Here, the production of propionic acid (PA), a potential building block for C3-based chemicals, from corn stover hydrolysate is investigated using the native PA-producing bacterium Propionibacterium acidipropionici. A wide range of culture conditions and process parameters were examined and experimentally optimized to maximize titer, rate, and yield of PA. The effect of gas sparging during fermentation was first examined, and N 2 was found to exhibit improved performance over CO 2. Subsequently, the effects of different hydrolysate concentrations, nitrogen sources, and neutralization agentsmore » were investigated. One of the best combinations found during batch experiments used yeast extract (YE) as the primary nitrogen source and NH 4OH for pH control. This combination enabled PA titers of 30.8 g/L with a productivity of 0.40 g/L h from 76.8 g/L biomass sugars, while successfully minimizing lactic acid production. Due to the economic significance of downstream separations, increasing titers using fed-batch fermentation was examined by changing both feeding media and strategy. Continuous feeding of hydrolysate was found to be superior to pulsed feeding and combined with high YE concentrations increased PA titers to 62.7 g/L and improved the simultaneous utilization of different biomass sugars. Additionally, applying high YE supplementation maintains the lactic acid concentration below 4 g/L for the duration of the fermentation. Finally, with the aim of increasing productivity, high cell density fed-batch fermentations were conducted. PA titers increased to 64.7 g/L with a productivity of 2.35 g/L h for the batch stage and 0.77 g/L h for the overall process. These results highlight the importance of media and fermentation strategy to improve PA production. Altogether, this work demonstrates the feasibility of

  2. Aspergillus oryzae-based cell factory for direct kojic acid production from cellulose.

    PubMed

    Yamada, Ryosuke; Yoshie, Toshihide; Wakai, Satoshi; Asai-Nakashima, Nanami; Okazaki, Fumiyoshi; Ogino, Chiaki; Hisada, Hiromoto; Tsutsumi, Hiroko; Hata, Yoji; Kondo, Akihiko

    2014-05-18

    Kojic acid (5-Hydroxy-2-(hydroxymethyl)-4-pyrone) is one of the major secondary metabolites in Aspergillus oryzae. It is widely used in food, pharmaceuticals, and cosmetics. The production cost, however, is too high for its use in many applications. Thus, an efficient and cost-effective kojic acid production process would be valuable. However, little is known about the complete set of genes for kojic acid production. Currently, kojic acid is produced from glucose. The efficient production of kojic acid using cellulose as an inexpensive substrate would help establish cost-effective kojic acid production. A kojic acid transcription factor gene over-expressing the A. oryzae strain was constructed. Three genes related to kojic acid production in this strain were transcribed in higher amounts than those found in the wild-type strain. This strain produced 26.4 g/L kojic acid from 80 g/L glucose. Furthermore, this strain was transformed with plasmid harboring 3 cellulase genes. The resultant A. oryzae strain successfully produced 0.18 g/L of kojic acid in 6 days of fermentation from the phosphoric acid swollen cellulose. Kojic acid was produced directly from cellulose material using genetically engineered A. oryzae. Because A. oryzae has efficient protein secretion ability and secondary metabolite productivity, an A. oryzae-based cell factory could be a platform for the production of various kinds of bio-based chemicals.

  3. Critical considerations for developing nucleic acid macromolecule based drug products.

    PubMed

    Muralidhara, Bilikallahalli K; Baid, Rinku; Bishop, Steve M; Huang, Min; Wang, Wei; Nema, Sandeep

    2016-03-01

    Protein expression therapy using nucleic acid macromolecules (NAMs) as a new paradigm in medicine has recently gained immense therapeutic potential. With the advancement of nonviral delivery it has been possible to target NAMs against cancer, immunodeficiency and infectious diseases. Owing to the complex and fragile structure of NAMs, however, development of a suitable, stable formulation for a reasonable product shelf-life and efficacious delivery is indeed challenging to achieve. This review provides a synopsis of challenges in the formulation and stability of DNA/m-RNA based medicines and probable mitigation strategies including a brief summary of delivery options to the target cells. Nucleic acid based drugs at various stages of ongoing clinical trials are compiled. Copyright © 2016. Published by Elsevier Ltd.

  4. Exploring the potential of lactic acid production from lignocellulosic hydrolysates with various ratios of hexose versus pentose by Bacillus coagulans IPE22.

    PubMed

    Wang, Yujue; Cao, Weifeng; Luo, Jianquan; Wan, Yinhua

    2018-08-01

    The aim of this study was to investigate the feasibility of utilizing different lignocellulosic hydrolysates with various hexose versus pentose (H:P) ratios to produce lactic acid (LA) from Bacillus coagulans IPE22 by fermentations with single and mixed sugar. In single sugar utilization, glucose tended to promote LA production, and xylose preferred to enhance cell growth. In mixed sugar utilization, glucose and pentose were consumed simultaneously when glucose concentration was lower than 20 g/L, and almost the same concentration of LA (50 g/L) was obtained regardless of the differences of H:P values. Finally, LA production from corn cob hydrolysates (CCH) contained 60 g/L mixed sugar verified the mechanisms found in the fermentations with simulated sugar mixture. Comparing with single glucose utilization, CCH utilization was faster and the yield of LA was not significantly affected. Therefore, the great potential of producing LA with lignocellulosic materials by B. coagulans was proved. Copyright © 2018. Published by Elsevier Ltd.

  5. Cultivation characteristics of immobilized Aspergillus oryzae for kojic acid production.

    PubMed

    Kwak, M Y; Rhee, J S

    1992-04-15

    Aspergillus oryzae in situ grown from spores entrapped in calcium alginate gel beads was used for the production of kojic acid. The immobilized cells in flask cultures produced kojic acid in a linear proportion while maintaining the stable metabolic activity for a prolonged production period. Kojic acid was accumulated up to a high concentration of 83 g/L, at which the kojic acid began to crystallize, and, thus, the culture had to be replaced with fresh media for the next batch culture. The overall productivities of two consecutive cultivations were higher than that of free mycelial fermentation. However, the production rate of kojic acid by the immobilized cells was suddenly decreased with the appearance of central cavernae inside the immobilized gel beads after 12 days of the third batch cultivation.

  6. Biotechnological production of alpha-keto acids: Current status and perspectives.

    PubMed

    Song, Yang; Li, Jianghua; Shin, Hyun-Dong; Liu, Long; Du, Guocheng; Chen, Jian

    2016-11-01

    Alpha-keto (α-keto) acids are used widely in feeds, food additives, pharmaceuticals, and in chemical synthesis processes. Although most α-keto acids are currently produced by chemical synthesis, their biotechnological production from renewable carbohydrates is a promising new approach. In this mini-review, we first present the different types of α-keto acids as well as their applications; next, we summarize the recent progresses in the biotechnological production of some important α-keto acids; namely, pyruvate, α-ketoglutarate, α-ketoisovalerate, α-ketoisocaproate, phenylpyruvate, α-keto-γ-methylthiobutyrate, and 2,5-diketo-d-gluconate. Finally, we discuss the future prospects as well as favorable directions for the biotechnological production of keto acids that ultimately would be more environment-friendly and simpler compared with the production by chemical synthesis. Copyright © 2016. Published by Elsevier Ltd.

  7. Cumulative irritation potential of metronidazole gel compared to azelaic acid gel after repeated applications to healthy skin.

    PubMed

    Ziel, Kristin; Yelverton, Christopher B; Balkrishnan, Rajesh; Feldman, Steven R

    2005-01-01

    Metronidazole 0.75% gel and azelaic acid 15% gel are commonly used to treat rosacea. Irritation is a common side effect. To assess the cumulative irritation potential of metronidazole 0.75% gel and azelaic acid 15% gel. Metronidazole 0.75% gel, azelaic acid 15% gel, and a white petrolatum negative control were applied under occlusive conditions to the upper back of a total of 33 healthy subjects. There were twelve 24-hour applications (4 times a week) and three 72-hour applications on weekends during a 3-week period. Skin reactions (erythema score +/- other local reaction) were assessed within 15 to 30 minutes of removal of the products. The mean cumulative irritancy index of metronidazole 0.75% gel was significantly lower than that of azelaic acid 15% gel and not significantly higher than the negative control product. There was increasing cumulative irritancy with azelaic acid; no cumulative irritancy was seen for either metronidazole or white petrolatum. Metronidazole 0.75% gel is less irritating in sustained use than azelaic acid 15% gel.

  8. Novel consortium of Klebsiella variicola and Lactobacillus species enhances the functional potential of fermented dairy products by increasing the availability of branched-chain amino acids and the amount of distinctive volatiles.

    PubMed

    Rosales-Bravo, H; Morales-Torres, H C; Vázquez-Martínez, J; Molina-Torres, J; Olalde-Portugal, V; Partida-Martínez, L P

    2017-11-01

    Identify novel bacterial taxa that could increase the availability of branched-chain amino acids and the amount of distinctive volatiles during skim milk fermentation. We recovered 344 bacterial isolates from stool samples of healthy and breastfed infants. Five were selected based on their ability to produce branched-chain amino acids. Three strains were identified as Escherichia coli, one as Klebsiella pneumoniae and other as Klebsiella variicola by molecular and biochemical methods. HPLC and solid-phase microextraction with GC-MS were used for the determination of free amino acids and volatile compounds respectively. The consortium formed by K. variicola and four Lactobacillus species showed the highest production of Leu and Ile in skim milk fermentation. In addition, the production of volatile compounds, such as acetoin, ethanol, 2-nonanone, and acetic, hexanoic and octanoic acids, increased in comparison to commercial yogurt, Emmental and Gouda cheese. Also, distinctive volatiles, such as 2,3-butanediol, 4-methyl-2- hexanone and octanol, were identified. The use of K. variicola in combination with probiotic Lactobacillus species enhances the availability of Leu and Ile and the amount of distinctive volatiles during skim milk fermentation. The identified consortium increases the functional potential of fermented dairy products. © 2017 The Society for Applied Microbiology.

  9. Biodiesel production using fatty acids from food industry waste using corona discharge plasma technology.

    PubMed

    Cubas, A L V; Machado, M M; Pinto, C R S C; Moecke, E H S; Dutra, A R A

    2016-01-01

    This article aims to describe an alternative and innovative methodology to transform waste, frying oil in a potential energy source, the biodiesel. The biodiesel was produced from fatty acids, using a waste product of the food industry as the raw material. The methodology to be described is the corona discharge plasma technology, which offers advantages such as acceleration of the esterification reaction, easy separation of the biodiesel and the elimination of waste generation. The best conditions were found to be an oil/methanol molar ratio of 6:1, ambient temperature (25 °C) and reaction time of 110 min and 30 mL of sample. The acid value indicates the content of free fatty acids in the biodiesel and the value obtained in this study was 0.43 mg KOH/g. Peaks corresponding to octadecadienoic acid methyl ester, octadecanoic acid methyl ester and octadecenoic acid methyl ester, from the biodiesel composition, were identified using GC-MS. A major advantage of this process is that the methyl ester can be obtained in the absence of chemical catalysts and without the formation of the co-product (glycerin). Copyright © 2015 Elsevier Ltd. All rights reserved.

  10. Production of L- and D-lactic acid from waste Curcuma longa biomass through simultaneous saccharification and cofermentation.

    PubMed

    Nguyen, Cuong Mai; Kim, Jin-Seog; Nguyen, Thanh Ngoc; Kim, Seul Ki; Choi, Gyung Ja; Choi, Yong Ho; Jang, Kyoung Soo; Kim, Jin-Cheol

    2013-10-01

    Simultaneous saccharification and cofermentation (SSCF) of Curcuma longa waste biomass obtained after turmeric extraction to L- and D-lactic acid by Lactobacillus coryniformis and Lactobacillus paracasei, respectively, was investigated. This is a rich, starchy, agro-industrial waste with potential for use in industrial applications. After optimizing the fermentation of the biomass by adjusting nitrogen sources, enzyme compositions, nitrogen concentrations, and raw material concentrations, the SSCF process was conducted in a 7-l jar fermentor at 140 g dried material/L. The maximum lactic acid concentration, average productivity, reducing sugar conversion and lactic acid yield were 97.13 g/L, 2.7 g/L/h, 95.99% and 69.38 g/100 g dried material for L-lactic acid production, respectively and 91.61 g/L, 2.08 g/L/h, 90.53% and 65.43 g/100 g dried material for D-lactic acid production, respectively. The simple and efficient process described in this study could be utilized by C. longa residue-based lactic acid industries without requiring the alteration of plant equipment. Copyright © 2013 Elsevier Ltd. All rights reserved.

  11. Production of sugars and levulinic acid from marine biomass Gelidium amansii.

    PubMed

    Jeong, Gwi-Taek; Park, Don-Hee

    2010-05-01

    This study focused on optimization of reaction conditions for formation of sugars and levulinic acid from marine algal biomass Gelidium amansii using acid catalyst and by using statistical approach. By this approach, optimal conditions for production of sugars and levulinic acid were found as follows: glucose (reaction temperature of 139.4 degrees C, reaction time of 15.0 min, and catalyst concentration of 3.0%), galactose (108.2 degrees C, 45.0 min, and 3.0%), and levulinic acid (160.0 degrees C, 43.1 min, and 3.0%). While trying to optimize the conditions for the production of glucose and galactose, levulinic acid production was found to be minimum. Similarly, the production of glucose and galactose were found to be minimum while optimizing the conditions for the production of levulinic acid. In addition, optimized production of glucose required a higher reaction temperature and shorter reaction time than that of galactose. Levulinic acid was formed at a high reaction temperature, long reaction time, and high catalyst concentration. The combined results of this study may provide useful information to develop more economical and efficient systems for production of sugars and chemicals from marine biomass.

  12. Developing cellulosic waste products as platform chemicals: protecting group chemistry of α-glucoisosaccharinic acid.

    PubMed

    Almond, Michael; Suleiman, Mustapha G; Hawkins, Matthew; Winder, Daniel; Robshaw, Thomas; Waddoups, Megan; Humphreys, Paul N; Laws, Andrew P

    2018-01-02

    Alpha and beta-glucoisosaccharinic acids ((2S,4S)-2,4,5-trihydroxy-2-(hydroxymethyl)pentanoic acid and (2R,4S)-2,4,5-trihydroxy-2-(hydroxymethyl)pentanoic acid) which are produced when cellulosic materials are treated with aqueous alkali are potentially valuable platform chemicals. Their highly functionalised carbon skeleton, with fixed chirality at C-2 and C-4, makes them ideal starting materials for use in synthesis. In order to assess the potential of these saccharinic acids as platform chemicals we have explored the protecting group chemistry of the lactone form of alpha-glucoisosaccharinic acid (α-GISAL). We report here the use of single and multiple step reaction pathways leading to the regioselective protection of the three different hydroxyl groups of α-GISAL. We report strategies for protecting the three different hydroxyl groups individually or in pairs. We also report the synthesis of a range of tri-O-protected α-GISAL derivatives where a number of the products contain orthogonal protecting groups. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Industrial production of L-ascorbic Acid (vitamin C) and D-isoascorbic acid.

    PubMed

    Pappenberger, Günter; Hohmann, Hans-Peter

    2014-01-01

    L-ascorbic acid (vitamin C) was first isolated in 1928 and subsequently identified as the long-sought antiscorbutic factor. Industrially produced L-ascorbic acid is widely used in the feed, food, and pharmaceutical sector as nutritional supplement and preservative, making use of its antioxidative properties. Until recently, the Reichstein-Grüssner process, designed in 1933, was the main industrial route. Here, D-sorbitol is converted to L-ascorbic acid via 2-keto-L-gulonic acid (2KGA) as key intermediate, using a bio-oxidation with Gluconobacter oxydans and several chemical steps. Today, industrial production processes use additional bio-oxidation steps with Ketogulonicigenium vulgare as biocatalyst to convert D-sorbitol to the intermediate 2KGA without chemical steps. The enzymes involved are characterized by a broad substrate range, but remarkable regiospecificity. This puzzling specificity pattern can be understood from the preferences of these enyzmes for certain of the many isomeric structures which the carbohydrate substrates adopt in aqueous solution. Recently, novel enzymes were identified that generate L-ascorbic acid directly via oxidation of L-sorbosone, an intermediate of the bio-oxidation of D-sorbitol to 2KGA. This opens the possibility for a direct route from D-sorbitol to L-ascorbic acid, obviating the need for chemical rearrangement of 2KGA. Similar concepts for industrial processes apply for the production of D-isoascorbic acid, the C5 epimer of L-ascorbic acid. D-isoascorbic acid has the same conformation at C5 as D-glucose and can be derived more directly than L-ascorbic acid from this common carbohydrate feed stock.

  14. Production of humic acids from oil palm empty fruit bunch by submerged fermentation with Trichoderma viride: cellulosic substrates and nitrogen sources.

    PubMed

    Motta, F L; Santana, M H A

    2013-01-01

    The novelty of this study was to produce humic acids by submerged fermentation of empty fruit bunch (EFB) with Trichoderma viride and to investigate the effects of the cellulosic substrates and the organic sources of nitrogen on the biotechnological production of these acids. The results obtained indicate the potential application of EFB, a waste of oil palm processing, for humic acids production. Because EFB contains cellulose, hemicellulose and lignin, fermentations were also performed using these polymers as carbon sources, separately or in combination. After 120 h of fermentation, significant production of humic acids was observed only in cultures containing either EFB or a mixture of the three polymers. Use of either potato peptone or yeast extract as a nitrogen source yielded nearly identical patterns of fungal growth and production of humic acids. The data obtained from microscopic imaging of T. viride growth and sporulation in EFB, coupled with the determined rates of production of humic acids indicated that the production of these acids is related to T. viride sporulation. © 2013 American Institute of Chemical Engineers.

  15. Potential effects of chlorogenic acids on platelet activiation

    USDA-ARS?s Scientific Manuscript database

    Coffee (Coffea sp) is a most consumed beverage world-wide. Chlorogenic acids (CHAs) are naturally occurring phenolic acid esters abundantly found in coffee. They are reported to have potential health effects on several chronic diseases such as obesity, diabetes and cardiovascular diseases (CVD). At...

  16. Determination of acid forming potential of massive sulfide minerals and the tailings situated in lead/zinc mining district of Balya (NW Turkey)

    NASA Astrophysics Data System (ADS)

    Çelebi, E. Ender; Öncel, M. Salim

    2016-12-01

    Weathering of sulfide minerals is a major source of acid production in nature and especially in mining territories. Pyrite is not the only principal mineral that generates acid drainage: other sulfide minerals (sphalerite, galena, chalcopyrite, etc.) may also be responsible for acid production. In addition to massive sulfide minerals, sulfide-bearing mine tailings may also produce acid drainage due to oxidation and hydrolysis reactions in waste dumps. The lead/zinc (Pb/Zn) mining region in Balya and Balıkesir, in Turkey, has operated mines intensively since the 1860s; so that characterization of the sulfide minerals and tailings situated and formed around the mining site is of great importance to secure a sustainable environment. For this purpose, acid production and neutralization potentials of massive sulfide ores of the region, and in the Pb/Zn process facility mine tailings from ten different points of tailings dam, have been determined by applied conventional Acid-Base Accounting (ABA) and Net Acid Generation (NAG) static tests after chemical and mineralogical analysis. The NAG pH and net acid production potential (NAPP) values were compared on a chart in order to classify the samples as either acid generating or non-acid generating. According to the comparisons, the sulfide minerals were classified as potentially acid forming (PAF). Massive pyrite had the highest NAPP and NAG pH value of 1966.6 kg H2SO4/ton and 1.91, respectively and the galena had the lowest NAPP value of 558.9 kg H2SO4/ton. However, the sphalerite NAG leachate pH value of 4.30 was the highest in sulfide minerals so that the sphalerite plotted near the uncertainty reference border in the PAF zone. In the mine tailings, NAPP values of 105.9 kg H2SO4/ton on average and the NAG pH values of over 7.5 were determined. In addition to these tests, water leaching (agitation test) was carried out on tailings in order to generate more information. The tailings did not generate acidic leachates as

  17. Polyunsaturated Fatty Acids of Marine Macroalgae: Potential for Nutritional and Pharmaceutical Applications

    PubMed Central

    Pereira, Hugo; Barreira, Luísa; Figueiredo, Filipe; Custódio, Luísa; Vizetto-Duarte, Catarina; Polo, Cristina; Rešek, Eva; Engelen, Aschwin; Varela, João

    2012-01-01

    As mammals are unable to synthesize essential polyunsaturated fatty acids (PUFA), these compounds need to be taken in through diet. Nowadays, obtaining essential PUFA in diet is becoming increasingly difficult; therefore this work investigated the suitability of using macroalgae as novel dietary sources of PUFA. Hence, 17 macroalgal species from three different phyla (Chlorophyta, Phaeophyta and Rhodophyta) were analyzed and their fatty acid methyl esters (FAME) profile was assessed. Each phylum presented a characteristic fatty acid signature as evidenced by clustering of PUFA profiles of algae belonging to the same phylum in a Principal Components Analysis. The major PUFA detected in all phyla were C18 and C20, namely linoleic, arachidonic and eicosapentaenoic acids. The obtained data showed that rhodophytes and phaeophytes have higher concentrations of PUFA, particularly from the n-3 series, thereby being a better source of these compounds. Moreover, rhodophytes and phaeophytes presented “healthier” ∑n-6/∑n-3 and PUFA/saturated fatty acid ratios than chlorophytes. Ulva was an exception within the Chlorophyta, as it presented high concentrations of n-3 PUFA, α-linolenic acid in particular. In conclusion, macroalgae can be considered as a potential source for large-scale production of essential PUFA with wide applications in the nutraceutical and pharmacological industries. PMID:23118712

  18. Biotechnological production of gluconic acid: future implications.

    PubMed

    Singh, Om V; Kumar, Raj

    2007-06-01

    Gluconic acid (GA) is a multifunctional carbonic acid regarded as a bulk chemical in the food, feed, beverage, textile, pharmaceutical, and construction industries. The favored production process is submerged fermentation by Aspergillus niger utilizing glucose as a major carbohydrate source, which accompanied product yield of 98%. However, use of GA and its derivatives is currently restricted because of high prices: about US$ 1.20-8.50/kg. Advancements in biotechnology such as screening of microorganisms, immobilization techniques, and modifications in fermentation process for continuous fermentation, including genetic engineering programmes, could lead to cost-effective production of GA. Among alternative carbohydrate sources, sugarcane molasses, grape must show highest GA yield of 95.8%, and banana must may assist reducing the overall cost of GA production. These methodologies would open new markets and increase applications of GA.

  19. Aspergillus oryzae-based cell factory for direct kojic acid production from cellulose

    PubMed Central

    2014-01-01

    Background Kojic acid (5-Hydroxy-2-(hydroxymethyl)-4-pyrone) is one of the major secondary metabolites in Aspergillus oryzae. It is widely used in food, pharmaceuticals, and cosmetics. The production cost, however, is too high for its use in many applications. Thus, an efficient and cost-effective kojic acid production process would be valuable. However, little is known about the complete set of genes for kojic acid production. Currently, kojic acid is produced from glucose. The efficient production of kojic acid using cellulose as an inexpensive substrate would help establish cost-effective kojic acid production. Results A kojic acid transcription factor gene over-expressing the A. oryzae strain was constructed. Three genes related to kojic acid production in this strain were transcribed in higher amounts than those found in the wild-type strain. This strain produced 26.4 g/L kojic acid from 80 g/L glucose. Furthermore, this strain was transformed with plasmid harboring 3 cellulase genes. The resultant A. oryzae strain successfully produced 0.18 g/L of kojic acid in 6 days of fermentation from the phosphoric acid swollen cellulose. Conclusions Kojic acid was produced directly from cellulose material using genetically engineered A. oryzae. Because A. oryzae has efficient protein secretion ability and secondary metabolite productivity, an A. oryzae-based cell factory could be a platform for the production of various kinds of bio-based chemicals. PMID:24885968

  20. Enhanced succinic acid production by Actinobacillus succinogenes after genome shuffling.

    PubMed

    Zheng, Pu; Zhang, Kunkun; Yan, Qiang; Xu, Yan; Sun, Zhihao

    2013-08-01

    Succinic acid is an important platform chemical for synthesis of C4 compounds. We applied genome shuffling to improve fermentative production of succinic acid by A. succinogenes. Using a screening strategy composed of selection in fermentation broth, cultured in 96-deep-well plates, and condensed HPLC screening, a starting population of 11 mutants producing a higher succinic acid concentration was selected and subjected to recursive protoplasts fusion. After three rounds of genome shuffling, strain F3-II-3-F was obtained, producing succinic acid at 1.99 g/l/h with a yield of 95.6 g/l. The genome shuffled strain had about a 73 % improvement in succinic acid production compared to the parent strain after 48 h in fed-batch fermentation. The genomic variability of F3-II-3-F was confirmed by amplified fragment-length polymorphism. The activity levels of key enzymes involved in end-product formation from glucose and metabolic flux distribution during succinic acid production were compared between A. succinogenes CGMCC 1593 and F3-II-3-F. Increased activity of glucokinase, fructose-1,6-bisphosphate aldolase, PEP carboxykinase and fumarase, as well as decreased activity of pyruvate kinase, pyruvate formate-lyase, and acetate kinase explained the enhanced succinic acid production and decreased acetic acid formation. Metabolic flux analysis suggested that increased flux to NADH was the main reason for increased activity of the C4 pathway resulting in increased yields of succinic acid. The present work will be propitious to the development of a bio-succinic acid fermentation industry.

  1. 40 CFR 721.4461 - Hydrofluoric acid, reaction products with octane (generic).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Hydrofluoric acid, reaction products... New Uses for Specific Chemical Substances § 721.4461 Hydrofluoric acid, reaction products with octane... identified generically as a hydrofluoric acid, reaction products with octane (PMN P-99-0052) is subject to...

  2. 40 CFR 721.4461 - Hydrofluoric acid, reaction products with octane (generic).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Hydrofluoric acid, reaction products... New Uses for Specific Chemical Substances § 721.4461 Hydrofluoric acid, reaction products with octane... identified generically as a hydrofluoric acid, reaction products with octane (PMN P-99-0052) is subject to...

  3. 40 CFR 415.280 - Applicability; description of the boric acid production subcategory.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... boric acid production subcategory. 415.280 Section 415.280 Protection of Environment ENVIRONMENTAL... SOURCE CATEGORY Boric Acid Production Subcategory § 415.280 Applicability; description of the boric acid... production of boric acid from ore-mined borax and from borax produced by the Trona process. ...

  4. Highly efficient production of optically pure l-lactic acid from corn stover hydrolysate by thermophilic Bacillus coagulans.

    PubMed

    Ma, Kedong; Hu, Guoquan; Pan, Liwei; Wang, Zichao; Zhou, Yi; Wang, Yanwei; Ruan, Zhiyong; He, Mingxiong

    2016-11-01

    A thermophilic strain Bacillus coagulans (NBRC 12714) was employed to produce l-lactic acid from corn stover hydrolysate in membrane integrated continuous fermentation. The strain NBRC 12714 metabolized glucose and xylose by the Embden-Meyerhof-Parnas pathway (EMP) and the pentose phosphate pathway (PPP), producing l-lactic acid with optical purity >99.5%. The overall l-lactic acid titer of 92g/l with a yield of 0.91g/g and a productivity of 13.8g/l/h were achieved at a dilution rate of 0.15h(-1). The productivity obtained was 1.6-fold than that of conventional continuous fermentation without cell recycling, and also was the highest among the relevant studies ever reported. These results indicated that the process developed had great potential for economical industrial production of l-lactic acid from lignocellulosic biomass. Copyright © 2016 Elsevier Ltd. All rights reserved.

  5. Very high gravity ethanol and fatty acid production of Zymomonas mobilis without amino acid and vitamin.

    PubMed

    Wang, Haoyong; Cao, Shangzhi; Wang, William Tianshuo; Wang, Kaven Tianyv; Jia, Xianhui

    2016-06-01

    Very high gravity (VHG) fermentation is the mainstream technology in ethanol industry, which requires the strains be resistant to multiple stresses such as high glucose concentration, high ethanol concentration, high temperature and harsh acidic conditions. To our knowledge, it was not reported previously that any ethanol-producing microbe showed a high performance in VHG fermentations without amino acid and vitamin. Here we demonstrate the engineering of a xylose utilizing recombinant Zymomonas mobilis for VHG ethanol fermentations. The recombinant strain can produce ethanol up to 136 g/L without amino acid and vitamin with a theoretical yield of 90 %, which is significantly superior to that produced by all the reported ethanol-producing strains. The intracellular fatty acids of the bacterial were about 16 % of the bacterial dry biomass, with the ratio of ethanol:fatty acids was about 273:1 (g/g). The recombinant strain was achieved by a multivariate-modular strategy tackles with the multiple stresses which are closely linked to the ethanol productivity of Z. mobilis. The over-expression of metB/yfdZ operon enabled the growth of the recombinant Z. mobilis in a chemically defined medium without amino acid and vitamin; and the fatty acids overproduction significantly increased ethanol tolerance and ethanol production. The coupled production of ethanol with fatty acids of the Z. mobilis without amino acid and vitamin under VHG fermentation conditions may permit a significant reduction of the production cost of ethanol and microbial fatty acids.

  6. Formic acid production using a microbial electrolysis desalination and chemical-production cell.

    PubMed

    Lu, Yaobin; Luo, Haiping; Yang, Kunpeng; Liu, Guangli; Zhang, Renduo; Li, Xiao; Ye, Bo

    2017-11-01

    The aim of this study was to investigate the feasibility and optimization of formic acid production in the microbial electrolysis desalination and chemical-production cell (MEDCC). The maximum current density in the MEDCC with 72cm of the anode fiber length (72-MEDCC) reached 24.0±2.0A/m 2 , which was much higher than previously reported. The maximum average formic acid production rate in the 72-MEDCC was 5.28 times higher than that in the MEDCC with 24cm of the anode fiber length (37.00±1.15vs. 7.00±0.25mg/h). High performance in the 72-MEDCC was attributed to small membrane spacing (1mm), high flow rate (1500μL/min) on the membrane surface and high anode biomass. The minimum electricity consumption of 0.34±0.04kWh/kg in the 72-MEDCC was only 3.1-18.8% of those in the EDBMs. The MEDCC should be a promising technology for the formic acid production. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. Fatty acids from VLDL lipolysis products induce lipid droplet accumulation in human monocytes

    PubMed Central

    den Hartigh, Laura J; Connolly-Rohrbach, Jaime E; Fore, Samantha; Huser, Thomas R; Rutledge, John C

    2010-01-01

    One mechanism by which monocytes become activated postprandially is by exposure to triglyceride (TG)-rich lipoproteins such as very low-density lipoproteins (VLDL). VLDL are hydrolyzed by lipoprotein lipase (LpL) at the blood-endothelial cell interface, releasing free fatty acids. In this study, we examined postprandial monocyte activation in more detail, and found that lipolysis products generated from postprandial VLDL induce the formation of lipid-filled droplets within cultured THP-1 monocytes, characterized by coherent anti-stokes Raman spectroscopy. Organelle-specific stains revealed an association of lipid droplets with the endoplasmic reticulum, confirmed by electron microscopy. Lipid droplet formation was reduced when LpL-released fatty acids were bound by bovine serum albumin, which also reduced cellular inflammation. Furthermore, saturated fatty acids induced more lipid droplet formation in monocytes compared to mono- and polyunsaturated fatty acids. Monocytes treated with postprandial VLDL lipolysis products contained lipid droplets with more intense saturated Raman spectroscopic signals than monocytes treated with fasting VLDL lipolysis products. In addition, we found that human monocytes isolated during the peak postprandial period contain more lipid droplets compared to those from the fasting state, signifying that their development is not limited to cultured cells but also occurs in vivo. In summary, circulating free fatty acids can mediate lipid droplet formation in monocytes and potentially be used as a biomarker to assess an individual’s risk of developing atherosclerotic cardiovascular disease. PMID:20208007

  8. High-level production of C-11-carboxyl-labeled amino acids. [For use in tumor and pancreatic imaging

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

    Washburn, L. C.; Sun, T. T.; Byrd, B. L.

    Carbon-11-labeled amino acids have significant potential as agents for positron tomographic functional imaging. We have developed a rapid, high-temperature, high-pressure modification of the Buecherer--Strecker amino acid synthesis and found it to be quite general for the production of C-11-carboxyl-labeled neutral amino acids. Production of C-11-carboxyl-labeled DL-tryptophan requires certain modifications in the procedure. Twelve different amino acids have been produced to date by this technique. Synthesis and chromatographic purification require approximately 40 min, and C-11-carboxyl-labeled amino acids have been produced in yields of up to 425 mCi. Two C-11-carboxyl-labeled amino acids are being investigated clinically for tumor scanning and two othersmore » for pancreatic imaging. Over 120 batches of the various agents have been produced for clinical use over a three-year period.« less

  9. Production of Odd-Carbon Dicarboxylic Acids in Escherichia coli Using an Engineered Biotin-Fatty Acid Biosynthetic Pathway.

    PubMed

    Haushalter, Robert W; Phelan, Ryan M; Hoh, Kristina M; Su, Cindy; Wang, George; Baidoo, Edward E K; Keasling, Jay D

    2017-04-05

    Dicarboxylic acids are commodity chemicals used in the production of plastics, polyesters, nylons, fragrances, and medications. Bio-based routes to dicarboxylic acids are gaining attention due to environmental concerns about petroleum-based production of these compounds. Some industrial applications require dicarboxylic acids with specific carbon chain lengths, including odd-carbon species. Biosynthetic pathways involving cytochrome P450-catalyzed oxidation of fatty acids in yeast and bacteria have been reported, but these systems produce almost exclusively even-carbon species. Here we report a novel pathway to odd-carbon dicarboxylic acids directly from glucose in Escherichia coli by employing an engineered pathway combining enzymes from biotin and fatty acid synthesis. Optimization of the pathway will lead to industrial strains for the production of valuable odd-carbon diacids.

  10. Use of corn steep liquor as an economical nitrogen source for biosuccinic acid production by Actinobacillus succinogenes

    NASA Astrophysics Data System (ADS)

    Tan, J. P.; Jahim, J. M.; Wu, T. Y.; Harun, S.; Mumtaz, T.

    2016-06-01

    Expensive raw materials are the driving force that leads to the shifting of the petroleum-based succinic acid production into bio-based succinic acid production by microorganisms. Cost of fermentation medium is among the main factors contributing to the total production cost of bio-succinic acid. After carbon source, nitrogen source is the second largest component of the fermentation medium, the cost of which has been overlooked for the past years. The current study aimed at replacing yeast extract- a costly nitrogen source with corn steep liquor for economical production of bio-succinic acid by Actinobacillus succinogenes 130Z. In this study, a final succinic acid concentration of 20.6 g/L was obtained from the use of corn steep liquor as the nitrogen source, which was comparable with the use of yeast extract as the nitrogen source that had a final succinate concentration of 21.4 g/l. In terms of economical wise, corn steep liquor was priced at 200 /ton, which was one fifth of the cost of yeast extract at 1000 /ton. Therefore, corn steep liquor can be considered as a potential nitrogen source in biochemical industries instead of the costly yeast extract.

  11. Metabolic engineering of Clostridium acetobutylicum for butyric acid production with high butyric acid selectivity.

    PubMed

    Jang, Yu-Sin; Im, Jung Ae; Choi, So Young; Lee, Jung Im; Lee, Sang Yup

    2014-05-01

    A typical characteristic of the butyric acid-producing Clostridium is coproduction of both butyric and acetic acids. Increasing the butyric acid selectivity important for economical butyric acid production has been rather difficult in clostridia due to their complex metabolic pathways. In this work, Clostridium acetobutylicum was metabolically engineered for highly selective butyric acid production. For this purpose, the second butyrate kinase of C. acetobutylicum encoded by the bukII gene instead of butyrate kinase I encoded by the buk gene was employed. Furthermore, metabolic pathways were engineered to further enhance the NADH-driving force. Batch fermentation of the metabolically engineered C. acetobutylicum strain HCBEKW (pta(-), buk(-), ctfB(-) and adhE1(-)) at pH 6.0 resulted in the production of 32.5g/L of butyric acid with a butyric-to-acetic acid ratio (BA/AA ratio) of 31.3g/g from 83.3g/L of glucose. By further knocking out the hydA gene (encoding hydrogenase) in the HCBEKW strain, the butyric acid titer was not further improved in batch fermentation. However, the BA/AA ratio (28.5g/g) obtained with the HYCBEKW strain (pta(-), buk(-), ctfB(-), adhE1(-) and hydA(-)) was 1.6 times higher than that (18.2g/g) obtained with the HCBEKW strain at pH 5.0, while no improvement was observed at pH 6.0. These results suggested that the buk gene knockout was essential to get a high butyric acid selectivity to acetic acid in C. acetobutylicum. Copyright © 2014 International Metabolic Engineering Society. Published by Elsevier Inc. All rights reserved.

  12. Improved eicosapentaenoic acid production in Pythium splendens RBB-5 based on metabolic regulation analysis.

    PubMed

    Ren, Liang; Zhou, Pengpeng; Zhu, Yuanmin; Zhang, Ruijiao; Yu, Longjiang

    2017-05-01

    Eicosapentaenoic acid (EPA) is an essential polyunsaturated fatty acid for human beings. At present, the production of commercially available long-chain polyunsaturated fatty acids, mainly from wild-caught ocean fish, is struggling to meet the increasing demand for EPA. Production of EPA by microorganisms may be an alternative, effective and economical method. The oleaginous fungus Pythium splendens RBB-5 is a potential source of EPA, and thanks to the simple culture conditions required, high yields can be achieved in a facile manner. In the study, lipid metabolomics was performed in an attempt to enhance EPA biosynthesis in Pythium splendens. Synthetic, metabolic regulation and gene expression analyses were conducted to clarify the mechanism of EPA biosynthesis, and guide optimization of EPA production. The results showed that the Δ 6 desaturase pathway is the main EPA biosynthetic route in this organism, and ∆ 6 , ∆ 12 and Δ 17 desaturases are the rate-limiting enzymes. All the three desaturase genes were separately introduced into the parent strain to increase the flow of fatty acids into the Δ 6 desaturase pathway. Enhanced expression of these key enzymes, in combination with improved regulation of metabolism, resulted in a maximum yield of 1.43 g/L in the D12 transgenic strain, which represents a tenfold increase over the parent strain before optimization. This is the higher EPA production yield yet reported for a microbial system. Our findings may allow the production of EPA at an industrial scale, and the strategy employed could be used to increase the production of EPA or other lipids in oleaginous microorganisms.

  13. 9-cis Retinoic Acid is the ALDH1A1 Product that Stimulates Melanogenesis

    PubMed Central

    Paterson, Elyse K.; Ho, Hsiang; Kapadia, Rubina; Ganesan, Anand K.

    2013-01-01

    Aldehyde dehydrogenase 1A1 (ALDH1A1), an enzyme that catalyzes the conversion of lipid aldehydes to lipid carboxylic acids, plays pleiotropic roles in UV-radiation resistance, melanogenesis, and stem cell maintenance. In this study, a combination of RNAi and pharmacologic approaches were used to determine which ALDH1A1 substrates and products regulate melanogenesis. Initial studies revealed that neither the UV-induced lipid aldehyde 4-hydroxy-2-nonenal nor the ALDH1A1 product all-trans retinoic acid appreciably induced melanogenesis. In contrast, both the ALDH1A1 substrate 9-cis retinal and its corresponding product 9-cis retinoic acid potently induced the accumulation of MITF mRNA, Tyrosinase mRNA, and melanin. ALDH1A1 depletion inhibited the ability of 9-cis retinal but not 9-cis retinoic acid to stimulate melanogenesis, indicating that ALDH1A1 regulates melanogenesis by catalyzing the conversion of 9-cis retinal to 9-cis retinoic acid. The addition of potent ALDH1A inhibitors (cyanamide or Angeli’s salt) suppressed Tyrosinase and MITF mRNA accumulation in vitro and also melanin accumulation in skin equivalents, suggesting that 9-cis retinoids regulate melanogenesis in the intact epidermis. Taken together, these studies not only identify cyanamide as a potential novel treatment for hyperpigmentary disorders, but also identify 9-cis retinoic acid as a pigment stimulatory agent that may have clinical utility in the treatment of hypopigmentary disorders, such as vitiligo. PMID:23489423

  14. Production of Δ9-tetrahydrocannabinolic acid from cannabigerolic acid by whole cells of Pichia (Komagataella) pastoris expressing Δ9-tetrahydrocannabinolic acid synthase from Cannabis sativa L.

    PubMed

    Zirpel, Bastian; Stehle, Felix; Kayser, Oliver

    2015-09-01

    The Δ9-tetrahydrocannabinolic acid synthase (THCAS) from Cannabis sativa was expressed intracellularly in different organisms to investigate the potential of a biotechnological production of Δ9-tetrahydrocannabinolic acid (THCA) using whole cells. Functional expression of THCAS was obtained in Saccharomyces cerevisiae and Pichia (Komagataella) pastoris using a signal peptide from the vacuolar protease, proteinase A. No functional expression was achieved in Escherichia coli. The highest volumetric activities obtained were 98 pkat ml(-1) (intracellular) and 44 pkat ml(-1) (extracellular) after 192 h of cultivation at 15 °C using P. pastoris cells. Low solubility of CBGA prevents the THCAS application in aqueous cell-free systems, thus whole cells were used for a bioconversion of cannabigerolic acid (CBGA) to THCA. Finally, 1 mM (0.36 g THCA l(-1)) THCA could be produced by 10.5 gCDW l(-1) before enzyme activity was lost. Whole cells of P. pastoris offer the capability of synthesizing pharmaceutical THCA production.

  15. Biotechnological Production of Caffeic Acid by Bacterial Cytochrome P450 CYP199A2

    PubMed Central

    Arai, Yuka; Kino, Kuniki

    2012-01-01

    Caffeic acid is a biologically active molecule that has various beneficial properties, including antioxidant, anticancer, and anti-inflammatory activities. In this study, we explored the catalytic potential of a bacterial cytochrome P450, CYP199A2, for the biotechnological production of caffeic acid. When the CYP199A2 enzyme was reacted with p-coumaric acid, it stoichiometrically produced caffeic acid. The crystal structure of CYP199A2 shows that Phe at position 185 is situated directly above, and only 6.35 Å from, the heme iron. This F185 residue was replaced with hydrophobic or hydroxylated amino acids using site-directed mutagenesis to create mutants with novel and improved catalytic properties. In whole-cell assays with the known substrate of CYP199A2, 2-naphthoic acid, only the wild-type enzyme hydroxylated 2-naphthoic acid at the C-7 and C-8 positions, whereas all of the active F185 mutants exhibited a preference for C-5 hydroxylation. Interestingly, several F185 mutants (F185V, F185L, F185I, F185G, and F185A mutants) also acquired the ability to hydroxylate cinnamic acid, which was not hydroxylated by the wild-type enzyme. These results demonstrate that F185 is an important residue that controls the regioselectivity and the substrate specificity of CYP199A2. Furthermore, Escherichia coli cells expressing the F185L mutant exhibited 5.5 times higher hydroxylation activity for p-coumaric acid than those expressing the wild-type enzyme. By using the F185L whole-cell catalyst, the production of caffeic acid reached 15 mM (2.8 g/liter), which is the highest level so far attained in biotechnological production of this compound. PMID:22729547

  16. Survival and Growth of Probiotic Lactic Acid Bacteria in Refrigerated Pickle Products.

    PubMed

    Fan, Sicun; Breidt, Fred; Price, Robert; Pérez-Díaz, Ilenys

    2017-01-01

    We examined 10 lactic acid bacteria that have been previously characterized for commercial use as probiotic cultures, mostly for dairy products, including 1 Pediococcus and 9 Lactobacilli. Our objectives were to develop a rapid procedure for determining the long-term survivability of these cultures in acidified vegetable products and to identify suitable cultures for probiotic brined vegetable products. We therefore developed assays to measure acid resistance of these cultures to lactic and acetic acids, which are present in pickled vegetable products. We used relatively high acid concentrations (compared to commercial products) of 360 mM lactic acid and 420 mM acetic acid to determine acid resistance with a 1 h treatment. Growth rates were measured in a cucumber juice medium at pH 5.3, 4.2, and 3.8, at 30 °C and 0% to 2% NaCl. Significant differences in acid resistance and growth rates were found among the 10 cultures. In general, the acid resistant strains had slower growth rates than the acid sensitive strains. Based on the acid resistance data, selected cultures were tested for long-term survival in a simulated acidified refrigerated cucumber product. We found that one of the most acid resistant strains (Lactobacillus casei) could survive for up to 63 d at 4 °C without significant loss of viability at 10 8 CFU/mL. These data may aid in the development of commercial probiotic refrigerated pickle products. © 2016 Institute of Food Technologists®.

  17. Optimal production of 7,10-dihydroxy-8(E)-hexadecenoic acid from palmitoleic acid by Pseudomonas aeruginosa PR3.

    PubMed

    Bae, Jae-Han; Suh, Min-Jung; Kim, Beom-Soo; Hou, Ching T; Lee, In-Jung; Kim, In-Hwan; Kim, Hak-Ryul

    2010-09-30

    The hydroxylation of unsaturated fatty acids by bacterial strains is one type of value-adding bioconversion processes. This process generates new hydroxy fatty acids (HFA) carrying special properties such as higher viscosity and reactivity compared with normal fatty acids. Among microbial strains tested for HFA production, Pseudomonas aeruginosa PR3 is well known to utilize various unsaturated fatty acids to produce mono-, di- and tri-hydroxy fatty acids. Previously we reported that strain PR3 could produce a novel value-added hydroxy fatty acid 7,10-dihydroxy-8(E)-hexadecenoic acid (DHD) from palmitoleic acid (Bae et al. (2007) Appl. Microbiol. Biotechnol. 75, 435-440). In this study, we focused on the development of the optimal nutritional and environmental conditions for DHD production from palmitoleic acid by PR3. Optimal carbon and nitrogen sources for DHD production were fructose and yeast extract, respectively. Optimal initial medium pH and incubation temperature were pH 8.0 and 30 degrees C and magnesium ion was essentially required for DHD production. Substrate concentration and time of substrate addition were also optimized. Under optimized conditions, maximal DHD production was 1600mg/l representing 26.7% conversion yield. Copyright 2009 Elsevier B.V. All rights reserved.

  18. 21 CFR 573.500 - Condensed, extracted glutamic acid fermentation product.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Condensed, extracted glutamic acid fermentation product. 573.500 Section 573.500 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND... fermentation product. Condensed, extracted glutamic acid fermentation product may be safely used in animal feed...

  19. Updates on industrial production of amino acids using Corynebacterium glutamicum.

    PubMed

    Wendisch, Volker F; Jorge, João M P; Pérez-García, Fernando; Sgobba, Elvira

    2016-06-01

    L-Amino acids find various applications in biotechnology. L-Glutamic acid and its salts are used as flavor enhancers. Other L-amino acids are used as food or feed additives, in parenteral nutrition or as building blocks for the chemical and pharmaceutical industries. L-amino acids are synthesized from precursors of central carbon metabolism. Based on the knowledge of the biochemical pathways microbial fermentation processes of food, feed and pharma amino acids have been developed. Production strains of Corynebacterium glutamicum, which has been used safely for more than 50 years in food biotechnology, and Escherichia coli are constantly improved using metabolic engineering approaches. Research towards new processes is ongoing. Fermentative production of L-amino acids in the million-ton-scale has shaped modern biotechnology and its markets continue to grow steadily. This review focusses on recent achievements in strain development for amino acid production including the use of CRISPRi/dCas9, genome-reduced strains, biosensors and synthetic pathways to enable utilization of alternative carbon sources.

  20. Biohydrogen and methane production via a two-step process using an acid pretreated native microalgae consortium.

    PubMed

    Carrillo-Reyes, Julian; Buitrón, Germán

    2016-12-01

    A native microalgae consortium treated under thermal-acidic hydrolysis was used to produce hydrogen and methane in a two-step sequential process. Different acid concentrations were tested, generating hydrogen and methane yields of up to 45mLH 2 gVS -1 and 432mLCH 4 gVS -1 , respectively. The hydrogen production step solubilized the particulate COD (chemical oxygen demand) up to 30%, creating considerable amounts of volatile fatty acids (up to 10gCODL -1 ). It was observed that lower acid concentration presented higher hydrogen and methane production potential. The results revealed that thermal acid hydrolysis of a native microalgae consortium is a simple but effective strategy for producing hydrogen and methane in the sequential process. In addition to COD removal (50-70%), this method resulted in an energy recovery of up to 15.9kJ per g of volatile solids of microalgae biomass, one of the highest reported. Copyright © 2016 Elsevier Ltd. All rights reserved.

  1. Cleaner production of citric acid by recycling its extraction wastewater treated with anaerobic digestion and electrodialysis in an integrated citric acid-methane production process.

    PubMed

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

    2015-01-01

    To solve the pollution problem of extraction wastewater in citric acid production, an integrated citric acid-methane production process was proposed. Extraction wastewater was treated through anaerobic digestion and the anaerobic digestion effluent (ADE) was recycled for the next batch of citric acid fermentation, thus eliminating wastewater discharge and reducing water consumption. Excessive Na(+) contained in ADE could significantly inhibit citric acid fermentation in recycling and was removed by electrodialysis in this paper. Electrodialysis performance was improved after pretreatment of ADE with air stripping and activated carbon adsorption to remove precipitable metal ions and pigments. Moreover, the concentrate water was recycled and mixed with feed to improve the water recovery rate above 95% in electrodialysis treatment, while the dilute water was collected for citric acid fermentation. The removal rate of Na(+) in ADE was above 95% and the citric acid production was even higher than that with tap water. Copyright © 2015 Elsevier Ltd. All rights reserved.

  2. Production of Odd-Carbon Dicarboxylic Acids in Escherichia coli Using an Engineered Biotin–Fatty Acid Biosynthetic Pathway

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

    Haushalter, Robert W.; Phelan, Ryan M.; Hoh, Kristina M.

    Dicarboxylic acids are commodity chemicals used in the production of plastics, polyesters, nylons, fragrances, and medications. Bio-based routes to dicarboxylic acids are gaining attention due to environmental concerns about petroleum-based production of these compounds. Some industrial applications require dicarboxylic acids with specific carbon chain lengths, including odd-carbon species. Biosynthetic pathways involving cytochrome P450-catalyzed oxidation of fatty acids in yeast and bacteria have been reported, but these systems produce almost exclusively even-carbon species. Here in this paper we report a novel pathway to odd-carbon dicarboxylic acids directly from glucose in Escherichia coli by employing an engineered pathway combining enzymes from biotinmore » and fatty acid synthesis. Optimization of the pathway will lead to industrial strains for the production of valuable odd-carbon diacids.« less

  3. Acid production in dental plaque after exposure to probiotic bacteria.

    PubMed

    Keller, Mette K; Twetman, Svante

    2012-10-24

    The increasing interest in probiotic lactobacilli in health maintenance has raised the question of potential risks. One possible side effect could be an increased acidogenicity in dental plaque. The aim of this study was to investigate the effect of probiotic lactobacilli on plaque lactic acid (LA) production in vitro and in vivo. In the first part (A), suspensions of two lactobacilli strains (L. reuteri DSM 17938, L. plantarum 299v) were added to suspensions of supragingival dental plaque collected from healthy young adults (n=25). LA production after fermentation with either xylitol or fructose was analyzed. In the second part (B), subjects (n=18) were given lozenges with probiotic lactobacilli (L. reuteri DSM 17938 and ATCC PTA 5289) or placebo for two weeks in a double-blinded, randomized cross-over trial. The concentration of LA in supragingival plaque samples was determined at baseline and after 2 weeks. Salivary counts of mutans streptococci (MS) and lactobacilli were estimated with chair-side methods. Plaque suspensions with L. reuteri DSM 17938 produced significantly less LA compared with L. plantarum 299v or controls (p<0.05). Fructose gave higher LA concentrations than xylitol. In part B, there were no significant differences in LA production between baseline and follow up in any of the groups and no differences between test and placebo were displayed. The salivary MS counts were not significantly altered during the intervention but the lactobacilli counts increased significantly in the test group (p<0.05). Lactic acid production in suspensions of plaque and probiotic lactobacilli was strain-dependant and the present study provides no evidence of an increase in plaque acidity by the supply of selected probiotic lactobacilli when challenged by fructose or xylitol. The study protocol was approved by The Danish National Committee on Biomedical Research Ethics (protocol no H-2-2010-112). NCT01700712.

  4. Nitrogenous compounds stimulate glucose-derived acid production by oral Streptococcus and Actinomyces.

    PubMed

    Norimatsu, Yuka; Kawashima, Junko; Takano-Yamamoto, Teruko; Takahashi, Nobuhiro

    2015-09-01

    Both Streptococcus and Actinomyces can produce acids from dietary sugars and are frequently found in caries lesions. In the oral cavity, nitrogenous compounds, such as peptides and amino acids, are provided continuously by saliva and crevicular gingival fluid. Given that these bacteria can also utilize nitrogen compounds for their growth, it was hypothesized that nitrogenous compounds may influence their acid production; however, no previous studies have examined this topic. Therefore, the present study aimed to assess the effects of nitrogenous compounds (tryptone and glutamate) on glucose-derived acid production by Streptococcus and Actinomyces. Acid production was evaluated using a pH-stat method under anaerobic conditions, whereas the amounts of metabolic end-products were quantified using high performance liquid chromatography. Tryptone enhanced glucose-derived acid production by up to 2.68-fold, whereas glutamate enhanced Streptococcus species only. However, neither tryptone nor glutamate altered the end-product profiles, indicating that the nitrogenous compounds stimulate the whole metabolic pathways involving in acid production from glucose, but are not actively metabolized, nor do they alter metabolic pathways. These results suggest that nitrogenous compounds in the oral cavity promote acid production by Streptococcus and Actinomyces in vivo. © 2015 The Societies and Wiley Publishing Asia Pty Ltd.

  5. Heterologous production and characterization of a chlorogenic acid esterase from Ustilago maydis with a potential use in baking.

    PubMed

    Nieter, Annabel; Kelle, Sebastian; Takenberg, Meike; Linke, Diana; Bunzel, Mirko; Popper, Lutz; Berger, Ralf G

    2016-10-15

    Ustilago maydis, an edible mushroom growing on maize (Zea mays), is consumed as the food delicacy huitlacoche in Mexico. A chlorogenic acid esterase from this basidiomycete was expressed in good yields cultivating the heterologous host Pichia pastoris on the 5L bioreactor scale (reUmChlE; 45.9UL(-1)). In contrast to previously described chlorogenic acid esterases, the reUmChlE was also active towards feruloylated saccharides. The enzyme preferred substrates with the ferulic acid esterified to the O-5 position of arabinose residues, typical of graminaceous monocots, over the O-2 position of arabinose or the O-6 position of galactose residues. Determination of kcat/Km showed that the reUmChlE hydrolyzed chlorogenic acid 18-fold more efficiently than methyl ferulate, p-coumarate or caffeate. Phenolic acids were released by reUmChlE from natural substrates, such as destarched wheat bran, sugar beet pectin and coffee pulp. Treatment of wheat dough using reUmChlE resulted in a noticeable softening indicating a potential application of the enzyme in bakery and confectionery. Copyright © 2016 Elsevier Ltd. All rights reserved.

  6. 2012: no trans fatty acids in Spanish bakery products.

    PubMed

    Ansorena, Diana; Echarte, Andrea; Ollé, Rebeca; Astiasarán, Iciar

    2013-05-01

    Trans fatty acids (TFA) are strongly correlated with an increased risk of cardiovascular and other chronic diseases. Current dietary recommendations exclude bakery products from frequent consumption basically due to their traditionally high content of TFA. The aim of this work was to analyse the lipid profile of different bakery products currently commercialised in Spain and with a conventionally high fat and TFA content. Premium and store brands for each product were included in the study. No significant amounts of TFA were found in any of the analysed products, regardless the brand. TFA content ranged between 0.17 g and 0.22 g/100 g product (mean=0.19 g/100 g product). Expressed on percentage of fatty acids, the maximum value was 0.87 g/100 g fatty acids and the mean value was 0.68%. These data are significantly lower than those observed in previously published papers for these types of products, and highlighted the importance of updating food composition databases in order to accurately estimate the real and current intake of TFA. Copyright © 2012 Elsevier Ltd. All rights reserved.

  7. Potential of fecal waste for the production of biomethane, bioethanol and biodiesel.

    PubMed

    Gomaa, Mohamed A; Abed, Raeid M M

    2017-07-10

    Fecal waste is an environmental burden that requires proper disposal, which ultimately becomes also an economic burden. Because fecal waste is nutrient-rich and contains a diverse methanogenic community, it has been utilized to produce biomethane via anaerobic digestion. Carbohydrates and lipids in fecal waste could reach up to 50% of the dry weight, which also suggests a potential as a feedstock for bioethanol and biodiesel production. We measured biomethane production from fecal waste of cows, chickens, goats and humans and compared the microbial community composition before and after anaerobic digestion. We also compared the fecal waste for cellulase production, saccharification and fermentation to produce bioethanol and for lipid content and fatty acid profiles to produce biodiesel. All fecal waste produced biomethane, with the highest yield of 433.4±77.1ml CH 4 /g VS from cow fecal waste. Production of bioethanol was achieved from all samples, with chicken fecal waste yielding as high as 1.6±0.25g/l. Sludge samples exhibited the highest extractable portion of lipids (20.9±0.08wt%) and conversion to fatty acid methyl esters (11.94wt%). Utilization of fecal waste for the production of biofuels is environmentally and economically beneficial. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. Optimization of odd chain fatty acid production by Yarrowia lipolytica.

    PubMed

    Park, Young-Kyoung; Dulermo, Thierry; Ledesma-Amaro, Rodrigo; Nicaud, Jean-Marc

    2018-01-01

    Odd chain fatty acids (odd FAs) have a wide range of applications in therapeutic and nutritional industries, as well as in chemical industries including biofuel. Yarrowia lipolytica is an oleaginous yeast considered a preferred microorganism for the production of lipid-derived biofuels and chemicals. However, it naturally produces negligible amounts of odd chain fatty acids. The possibility of producing odd FAs using Y. lipolytica was investigated. Y. lipolytica wild-type strain was shown able to grow on weak acids; acetate, lactate, and propionate. Maximal growth rate on propionate reached 0.24 ± 0.01 h -1 at 2 g/L, and growth inhibition occurred at concentration above 10 g/L. Wild-type strain accumulated lipids ranging from 7.39 to 8.14% (w/w DCW) depending on the carbon source composition, and odd FAs represented only 0.01-0.12 g/L. We here proved that the deletion of the PHD1 gene improved odd FAs production, which reached a ratio of 46.82% to total lipids. When this modification was transferred to an obese strain, engineered for improving lipid accumulation, further increase odd FAs production reaching a total of 0.57 g/L was shown. Finally, a fed-batch co-feeding strategy was optimized for further increase odd FAs production, which generated 0.75 g/L, the best production described so far in Y. lipolytica . A Y. lipolytica strain able to accumulate high level of odd chain fatty acids, mainly heptadecenoic acid, has been successfully developed. In addition, a fed-batch co-feeding strategy was optimized to further improve lipid accumulation and odd chain fatty acid content. These lipids enriched in odd chain fatty acid can (1) improve the properties of the biodiesel generated from Y. lipolytica lipids and (2) be used as renewable source of odd chain fatty acid for industrial applications. This work paves the way for further improvements in odd chain fatty acids and fatty acid-derived compound production.

  9. Comparing EPA production and fatty acid profiles of three Phaeodactylum tricornutum strains under western Norwegian climate conditions.

    PubMed

    Steinrücken, Pia; Prestegard, Siv Kristin; de Vree, Jeroen Hendrik; Storesund, Julia E; Pree, Bernadette; Mjøs, Svein Are; Erga, Svein Rune

    2018-03-01

    Microalgae could provide a sustainable alternative to fish oil as a source for the omega-3 polyunsaturated fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). However, growing microalgae on a large-scale is still more cost-intensive than fish oil production, and outdoor productivities vary greatly with reactor type, geographic location, climate conditions and microalgae species or even strains. The diatom Phaeodactylum tricornutum has been intensively investigated for its potential in large-scale production, due to its robustness and comparatively high growth rates and EPA content. Yet, most research have been performed in southern countries and with a single commercial P . tricornutum strain, while information about productivities at higher latitudes and of local strains is scarce. We examined the potential of the climate conditions in Bergen, western Norway for outdoor cultivation of P . tricornutum in flat panel photobioreactors and cultivated three different strains simultaneously, one commercial strain from Spain (Fito) and two local isolates (M28 and B58), to assess and compare their biomass and EPA productivities, and fatty acid (FA) profiles. The three strains possessed similar biomass productivities (average volumetric productivities of 0.20, 0.18, and 0.21 g L - 1  d - 1 ), that were lower compared to productivities reported from southern latitudes. However, EPA productivities differed between the strains (average volumetric productivities of 9.8, 5.7 and 6.9 mg L - 1  d - 1 ), due to differing EPA contents (average of 4.4, 3.2 and 3.1% of dry weight), and were comparable to results from Italy. The EPA content of strain Fito of 4.4% is higher than earlier reported for P . tricornutum (2.6-3.1%) and was only apparent under outdoor conditions. A principal component analysis (PCA) of the relative FA composition revealed strain-specific profiles. However, including data from laboratory experiments, revealed more significant

  10. Production of chlorogenic acid in Varthemia persica DC (var. persica) callus cultures

    PubMed Central

    Siahpoush, A.; Ghasemi, N.; Ardakani, M. Shams; Asghari, G.

    2011-01-01

    Chlorogenic acid, a pharmacologically important compound, is a phenolic compound that occurs in certain commonly used medicinal herbs. We looked for the presence of this compound in the callus cultures of Varthemia persica DC (var. persica). We have evaluated the conditions for establishment of callus cultures of V. persica and the in vitro production of chlorogenic acid. Callus was initiated by culturing seedling of V. persica on MS basal medium supplemented with different concentrations of kinetin, naphthalene acetic acid and 2,4-diphenoxy acetic acid. Also, the influence of light, and phytohormones on the production of chlorogenic acid was examined. Kinetin stimulated the production of chlorogenic acid. Replacement of 2,4-diphenoxy acetic acid with naphthalene acetic acid did not alter the chlorogenic acid production. The ability to induce the accumulation of chlorogenic acid in the V. persica callus cultures offers an opportunity to produce a phenolic compound with therapeutic value. PMID:22049279

  11. Selection of oleaginous yeasts for fatty acid production.

    PubMed

    Lamers, Dennis; van Biezen, Nick; Martens, Dirk; Peters, Linda; van de Zilver, Eric; Jacobs-van Dreumel, Nicole; Wijffels, René H; Lokman, Christien

    2016-05-27

    Oleaginous yeast species are an alternative for the production of lipids or triacylglycerides (TAGs). These yeasts are usually non-pathogenic and able to store TAGs ranging from 20 % to 70 % of their cell mass depending on culture conditions. TAGs originating from oleaginous yeasts can be used as the so-called second generation biofuels, which are based on non-food competing "waste carbon sources". In this study the selection of potentially new interesting oleaginous yeast strains is described. Important selection criteria were: a broad maximum temperature and pH range for growth (robustness of the strain), a broad spectrum of carbon sources that can be metabolized (preferably including C-5 sugars), a high total fatty acid content in combination with a low glycogen content and genetic accessibility. Based on these selection criteria, among 24 screened species, Schwanniomyces occidentalis (Debaromyces occidentalis) CBS2864 was selected as a promising strain for the production of high amounts of lipids.

  12. Simultaneous saccharification and fermentation of acid-pretreated rapeseed meal for succinic acid production using Actinobacillus succinogenes.

    PubMed

    Chen, Kequan; Zhang, Han; Miao, Yelian; Wei, Ping; Chen, Jieyu

    2011-04-07

    Rapeseed meal was evaluated for succinic acid production by simultaneous saccharification and fermentation using Actinobacillus succinogenes ATCC 55618. Diluted sulfuric acid pretreatment and subsequent hydrolysis with pectinase was used to release sugars from rapeseed meal. The effects of culture pH, pectinase loading and yeast extract concentration on succinic acid production were investigated. When simultaneous saccharification and fermentation of diluted acid pretreated rapeseed meal with a dry matter content of 12.5% (w/v) was performed at pH 6.4 and a pectinase loading of 2% (w/w, on dry matter) without supplementation of yeast extract, a succinic acid concentration of 15.5 g/L was obtained at a yield of 12.4 g/100g dry matter. Fed-batch simultaneous saccharification and fermentation was carried out with supplementation of concentrated pretreated rapeseed meal and pectinase at 18 and 28 h to yield a final dry matter content of 20.5% and pectinase loading of 2%, with the succinic acid concentration enhanced to 23.4 g/L at a yield of 11.5 g/100g dry matter and a productivity of 0.33 g/(Lh). This study suggests that rapeseed meal may be an alternative substrate for the efficient production of succinic acid by A. succinogenes without requiring nitrogen source supplementation. Copyright © 2011 Elsevier Inc. All rights reserved.

  13. Homo-fermentative production of D-lactic acid by Lactobacillus sp. employing casein whey permeate as a raw feed-stock.

    PubMed

    Prasad, Saurav; Srikanth, Katla; Limaye, Anil M; Sivaprakasam, Senthilkumar

    2014-06-01

    Casein whey permeate (CWP), a lactose-enriched dairy waste effluent, is a viable feed stock for the production of value-added products. Two lactic acid bacteria were cultivated in a synthetic casein whey permeate medium with or without pH control. Lactobacillus lactis ATCC 4797 produced D-lactic acid (DLA) at 12.5 g l(-1) in a bioreactor. The values of Leudking-Piret model parameters suggested that lactate was a growth-associated product. Batch fermentation was also performed employing CWP (35 g lactose l(-1)) with casein hydrolysate as a nitrogen supplement in a bioreactor. After 40 h, L. lactis produced 24.3 g lactic acid l(-1) with an optical purity >98 %. Thus CWP may be regarded as a potential feed-stock for DLA production.

  14. Vernonia galamensis, potential new crop source of epoxy acid

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

    Perdue, R.E. Jr.; Carlson, K.D.; Gilbert, M.G.

    Vernonia galamensis is a good source of seed oil rich in epoxy acid, which can be used to manufacture plastic formulations, protective coatings, and other products. Seed from a natural stand in Ethiopia contained 31% epoxy acid. Under cultivation in Kenya, this unimproved germ plasm produced a substantial yield of seed with 32% epoxy acid. This African species has good natural seed retention and is a promising new crop for semiarid tropical areas. 11 references.

  15. Top value platform chemicals: bio-based production of organic acids.

    PubMed

    Becker, Judith; Lange, Anna; Fabarius, Jonathan; Wittmann, Christoph

    2015-12-01

    Driven by the quest for sustainability, recent years have seen a tremendous progress in bio-based production routes from renewable raw materials to commercial goods. Particularly, the production of organic acids has crystallized as a competitive and fast-evolving field, related to the broad applicability of organic acids for direct use, as polymer building blocks, and as commodity chemicals. Here, we review recent advances in metabolic engineering and industrial market scenarios with focus on organic acids as top value products from biomass, accessible through fermentation and biotransformation. Copyright © 2015 Elsevier Ltd. All rights reserved.

  16. Urinary Urea, Uric Acid and Hippuric Acid as Potential Biomarkers in Multiple Sclerosis Patients.

    PubMed

    Atya, Hanaa B; Ali, Sahar A; Hegazy, Mohamed I; El Sharkawi, Fathia Z

    2018-04-01

    Urine is a proven source of metabolite biomarkers and has the potential to be a rapid, noninvasive, inexpensive, and efficient diagnostic tool for various human diseases. Despite these advantages, urine is an under-investigated source of biomarkers for multiple sclerosis (MS). The objective was to investigate the level of some urinary metabolites (urea, uric acid and hippuric acid) in patients with MS and correlate their levels to the severity of the disease, MS subtypes and MS treatment. The urine samples were collected from 73 MS patients-48 with RRMS and 25 with SPMS- and age matched 75 healthy controls. The values of urinary urea, uric acid and hippuric acid in MS patients were significantly decreased, and these metabolites in SPMS pattern showed significantly decrease than RRMS pattern. Also showed significant inverse correlation with expanded disability status scale and number of relapses. Accordingly, they may act as a potential urinary biomarkers for MS, and correlate to disease progression.

  17. Production of bio-sugar and bioethanol from coffee residue (CR) by acid-chlorite pretreatment.

    PubMed

    Kim, Ho Myeong; Choi, Yong-Soo; Lee, Dae-Seok; Kim, Yong-Hwan; Bae, Hyeun-Jong

    2017-07-01

    Nowadays, coffee residue (CR) after roasting is recognized as one of the most useful resources in the world for producing the biofuel and bio-materials. In this study, we evaluated the potential of bio-sugar and bioethanol production from acid-chlorite treated CR. Notably, CR treated three times with acid-chlorite after organic solvent extraction (OSE-3), showed the high monosaccharide content, and the efficient sugar conversion yield compared to the other pretreatment conditions. The OSE-3 (6% substrate loading, w/v) can produce bio-sugar (0.568g/g OSE-3). Also, simultaneous saccharification and fermentation (SSF) produced ethanol (0.266g/g OSE-3), and showed an ethanol conversion yield of 73.8% after a 72-h reaction period. These results suggest that acid-chlorite pretreatment can improve the bio-sugar and bioethanol production of CR by removing the phenolic and brown compounds. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. Catabolism of coniferyl aldehyde, ferulic acid and p-coumaric acid by Saccharomyces cerevisiae yields less toxic products.

    PubMed

    Adeboye, Peter Temitope; Bettiga, Maurizio; Aldaeus, Fredrik; Larsson, Per Tomas; Olsson, Lisbeth

    2015-09-21

    Lignocellulosic substrates and pulping process streams are of increasing relevance to biorefineries for second generation biofuels and biochemical production. They are known to be rich in sugars and inhibitors such as phenolic compounds, organic acids and furaldehydes. Phenolic compounds are a group of aromatic compounds known to be inhibitory to fermentative organisms. It is known that inhibition of Sacchromyces cerevisiae varies among phenolic compounds and the yeast is capable of in situ catabolic conversion and metabolism of some phenolic compounds. In an approach to engineer a S. cerevisiae strain with higher tolerance to phenolic inhibitors, we selectively investigated the metabolic conversion and physiological effects of coniferyl aldehyde, ferulic acid, and p-coumaric acid in Saccharomyces cerevisiae. Aerobic batch cultivations were separately performed with each of the three phenolic compounds. Conversion of each of the phenolic compounds was observed on time-based qualitative analysis of the culture broth to monitor various intermediate and final metabolites. Coniferyl aldehyde was rapidly converted within the first 24 h, while ferulic acid and p-coumaric acid were more slowly converted over a period of 72 h. The conversion of the three phenolic compounds was observed to involved several transient intermediates that were concurrently formed and converted to other phenolic products. Although there were several conversion products formed from coniferyl aldehyde, ferulic acid and p-coumaric acid, the conversion products profile from the three compounds were similar. On the physiology of Saccharomyces cerevisiae, the maximum specific growth rates of the yeast was not affected in the presence of coniferyl aldehyde or ferulic acid, but it was significantly reduced in the presence of p-coumaric acid. The biomass yields on glucose were reduced to 73 and 54 % of the control in the presence of coniferyl aldehyde and ferulic acid, respectively, biomass yield

  19. By-products from the biodiesel chain as a substrate to citric acid production by solid-state fermentation.

    PubMed

    Schneider, Manuella; Zimmer, Gabriela F; Cremonese, Ezequiel B; de C de S Schneider, Rosana; Corbellini, Valeriano A

    2014-07-01

    In this study, we propose the use of tung cake for the production of organic acids, with an emphasis on citric acid by solid-state fermentation. We evaluated the conditions of production and the by-products from the biodiesel chain as raw materials involved in this bioprocess. First, we standardized the conditions of solid-state fermentation in tung cake with and without residual fat and with different concentrations of glycerine using the fungus Aspergillus niger The solid-state fermentation process was monitored for 7 days considering the biomass growth and pH level. Citric acid production was determined by high-performance liquid chromatography. Fungal development was better in the crude tung cake, consisting of 20% glycerine. The highest citric acid yield was 350 g kg(-1) of biomass. Therefore, the solid-state fermentation of the tung cake with glycerine led to citric acid production using the Aspergillus niger fungus. © The Author(s) 2014.

  20. Identification of intermediates and assessment of ecotoxicity in the oxidation products generated during the ozonation of clofibric acid.

    PubMed

    Rosal, Roberto; Gonzalo, María S; Boltes, Karina; Letón, Pedro; Vaquero, Juan J; García-Calvo, E

    2009-12-30

    The degradation of an aqueous solution of clofibric acid was investigated during catalytic and non-catalytic ozonation. The catalyst, TiO(2), enhanced the production of hydroxyl radicals from ozone and raised the fraction or clofibric acid degraded by hydroxyl radicals. The rate constant for the reaction of clofibric acid and hydroxyl radicals was not affected by the presence of the catalyst. The toxicity of the oxidation products obtained during the reaction was assessed by means of Vibrio fischeri and Daphnia magna tests in order to evaluate the potential formation of toxic by-products. The results showed that the ozonation was enhanced by the presence of TiO(2,) the clofibric acid being removed completely after 15 min at pH 5. The evolution of dissolved organic carbon, specific ultraviolet absorption at 254 nm and the concentration of carboxylic acids monitored the degradation process. The formation of 4-chlorophenol, hydroquinone, 4-chlorocatechol, 2-hydroxyisobutyric acid and three non-aromatic compounds identified as a product of the ring-opening reaction was assessed by exact mass measurements performed by liquid chromatography coupled to time-of-flight mass spectrometry (LC-TOF-MS). The bioassays showed a significant increase in toxicity during the initial stages of ozonation following a toxicity pattern closely related to the formation of ring-opening by-products.

  1. Potential adverse effects of omega-3 Fatty acids in dogs and cats.

    PubMed

    Lenox, C E; Bauer, J E

    2013-01-01

    Fish oil omega-3 fatty acids, mainly eicosapentaenoic acid and docosahexaenoic acid, are used in the management of several diseases in companion animal medicine, many of which are inflammatory in nature. This review describes metabolic differences among omega-3 fatty acids and outlines potential adverse effects that may occur with their supplementation in dogs and cats with a special focus on omega-3 fatty acids from fish oil. Important potential adverse effects of omega-3 fatty acid supplementation include altered platelet function, gastrointestinal adverse effects, detrimental effects on wound healing, lipid peroxidation, potential for nutrient excess and toxin exposure, weight gain, altered immune function, effects on glycemic control and insulin sensitivity, and nutrient-drug interactions. Copyright © 2013 by the American College of Veterinary Internal Medicine.

  2. Rational Discovery of (+) (S) Abscisic Acid as a Potential Antifungal Agent: a Repurposing Approach.

    PubMed

    Khedr, Mohammed A; Massarotti, Alberto; Mohamed, Maged E

    2018-06-04

    Fungal infections are spreading widely worldwide, and the types of treatment are limited due to the lack of diverse therapeutic agents and their associated side effects and toxicity. The discovery of new antifungal classes is vital and critical. We discovered the antifungal activity of abscisic acid through a rational drug design methodology that included the building of homology models for fungal chorismate mutases and a pharmacophore model derived from a transition state inhibitor. Ligand-based virtual screening resulted in some hits that were filtered using molecular docking and molecular dynamic simulations studies. Both in silico methods and in vitro antifungal assays were used as tools to select and validate the abscisic acid repurposing. Abscisic acid inhibition assays confirmed the inhibitory effect of abscisic acid on chorismate mutase through the inhibition of phenylpyruvate production. The repositioning of abscisic acid, the well-known and naturally occurring plant growth regulator, as a potential antifungal agent because of its suggested action as an inhibitor to several fungal chorismate mutases was the main result of this work.

  3. High production of D-tagatose by the addition of boric acid.

    PubMed

    Lim, Byung-Chul; Kim, Hye-Jung; Oh, Deok-Kun

    2007-01-01

    An L-arabinose isomerase mutant enzyme from Geobacillus thermodenitrificans was used to catalyze the isomerization of D-galactose to D-tagatose with boric acid. Maximum production of D-tagatose occurred at pH 8.5-9.0, 60 degrees C, and 0.4 molar ratio of boric acid to D-galactose, and the production increased with increasing enzyme concentration. Under the optimum conditions, the enzyme (10.8 units/mL) converted 300 g/L D-galactose to 230 g/L D-tagatose for 20 h with a yield of 77% (w/w); the production and conversion yield with boric acid were 1.5-fold and 24% higher than without boric acid, respectively. In 24 h, the enzyme produced 370 g/L D-tagatose from 500 g/L D-galactose with boric acid, corresponding to a conversion yield of 74% (w/w) and a production rate of 15.4 g/L.h. The production and yield of D-tagatose obtained in this study are unprecedented.

  4. Biotechnology for improved hHydroxy fatty acid production in oilseed lesquerella

    USDA-ARS?s Scientific Manuscript database

    The conventional source of hydroxy fatty acid (HFA) is from castor (Ricinus communis), 90% of castor oil is ricinoleic acid (18:1OH). Ricinoleic acid and its derivatives are used as raw materials for numerous industrial products, such as lubricants, plasticizers and surfactants. The production of ca...

  5. Green and low-cost production of thermally stable and carboxylated cellulose Nanocrystals and nanofibrils using highly recyclable dicarboxylic acids

    Treesearch

    Huiyang Bian; Liheng Chen; Ruibin Wang; Junyong Zhu

    2016-01-01

    Here we demonstrate potentially low cost and green productions of high thermally stable and carboxylated cellulose nanocrystals (CNCs) and nanofibrils (CNF) from bleached eucalyptus pulp (BEP) and unbleached mixed hardwood kraft pulp (UMHP) fibers using highly recyclable dicarboxylic solid acids. Typical operating conditions were acid concentrations of 50 - 70 wt% at...

  6. Using multi-dimensional Smolyak interpolation to make a sum-of-products potential

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

    Avila, Gustavo, E-mail: Gustavo-Avila@telefonica.net; Carrington, Tucker, E-mail: Tucker.Carrington@queensu.ca

    2015-07-28

    We propose a new method for obtaining potential energy surfaces in sum-of-products (SOP) form. If the number of terms is small enough, a SOP potential surface significantly reduces the cost of quantum dynamics calculations by obviating the need to do multidimensional integrals by quadrature. The method is based on a Smolyak interpolation technique and uses polynomial-like or spectral basis functions and 1D Lagrange-type functions. When written in terms of the basis functions from which the Lagrange-type functions are built, the Smolyak interpolant has only a modest number of terms. The ideas are tested for HONO (nitrous acid)

  7. Comparison of efficacy of products containing azelaic acid in melasma treatment.

    PubMed

    Mazurek, Klaudia; Pierzchała, Ewa

    2016-09-01

    Melasma is one of the most frequently diagnosed hyperpigmentation changes on the skin of women's faces. Nearly 30% of women using oral estrogen therapy struggle with this problem. A common way of reducing melasma is the application of azelaic acid products. Comparison of efficacy of three dermocosmetic products, containing azelaic acid, in the reduction in melasma for women aged 35-55. A group of 60 women diagnosed with melasma were divided into three even, twenty-person subgroups. Each subgroup was assigned one dermocosmetic product containing azelaic acid. For 24 weeks, the patients applied the assigned product twice a day. The level of the colorant within the hyperpigmentation was marked before the treatment, after 1 month, after 3 months, and after 6 months of therapy. The pigmentation was measured using Mexameter(®) (Courage + Khazaka electronic, Germany). In addition, during each inspection, the patients' level of hydration, elasticity, and intensity of erythema was checked using Corneometer(®) , Reviscometer(®) . All dermocosmetics containing azelaic acid that were applied significantly contributed to the reduction in pigment in the pigmentary lesion. The largest decrease in the amount of pigment was observed in the first 3 months of use of the products. A combination containing 20% azelaic acid and mandelic acid, phytic acid, 4N-butyl resorcinol, and ferulic acid proved to be the most effective dermocosmetic III (Sesderma, Valencia, Spain). Dermocosmetics containing azelaic acid significantly contribute to the clearing of melasma. The effect depends on the treatment time, the acid concentration, and addition of other components. © 2016 Wiley Periodicals, Inc.

  8. Fatty acid production in genetically modified cyanobacteria

    PubMed Central

    Liu, Xinyao; Sheng, Jie; Curtiss III, Roy

    2011-01-01

    To avoid costly biomass recovery in photosynthetic microbial biofuel production, we genetically modified cyanobacteria to produce and secrete fatty acids. Starting with introducing an acyl–acyl carrier protein thioesterase gene, we made six successive generations of genetic modifications of cyanobacterium Synechocystis sp. PCC6803 wild type (SD100). The fatty acid secretion yield was increased to 197 ± 14 mg/L of culture in one improved strain at a cell density of 1.0 × 109 cells/mL by adding codon-optimized thioesterase genes and weakening polar cell wall layers. Although these strains exhibited damaged cell membranes at low cell densities, they grew more rapidly at high cell densities in late exponential and stationary phase and exhibited less cell damage than cells in wild-type cultures. Our results suggest that fatty acid secreting cyanobacteria are a promising technology for renewable biofuel production. PMID:21482809

  9. Potential of chicken by-products as sources of useful biological resources

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

    Lasekan, Adeseye; Abu Bakar, Fatimah, E-mail: fatim@putra.upm.edu.my; Halal Products Research Institute, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor

    By-products from different animal sources are currently being utilised for beneficial purposes. Chicken processing plants all over the world generate large amount of solid by-products in form of heads, legs, bones, viscera and feather. These wastes are often processed into livestock feed, fertilizers and pet foods or totally discarded. Inappropriate disposal of these wastes causes environmental pollution, diseases and loss of useful biological resources like protein, enzymes and lipids. Utilisation methods that make use of these biological components for producing value added products rather than the direct use of the actual waste material might be another viable option for dealingmore » with these wastes. This line of thought has consequently led to researches on these wastes as sources of protein hydrolysates, enzymes and polyunsaturated fatty acids. Due to the multi-applications of protein hydrolysates in various branches of science and industry, and the large body of literature reporting the conversion of animal wastes to hydrolysates, a large section of this review was devoted to this subject. Thus, this review reports the known functional and bioactive properties of hydrolysates derived from chicken by-products as well their utilisation as source of peptone in microbiological media. Methods of producing these hydrolysates including their microbiological safety are discussed. Based on the few references available in the literature, the potential of some chicken by-product as sources of proteases and polyunsaturated fatty acids are pointed out along with some other future applications.« less

  10. Allergenic potential of novel proteins - What can we learn from animal production?

    PubMed

    Ekmay, Ricardo D; Coon, Craig N; Ladics, Gregory S; Herman, Rod A

    2017-10-01

    Currently, risk assessment of the allergenic potential of novel proteins relies heavily on evaluating protein digestibility under normal conditions based on the theory that allergens are more resistant to gastrointestinal digestion than non-allergens. There is also proposed guidance for expanded in vitro digestibility assay conditions to include vulnerable sub-populations. One of the underlying rationales for the expanded guidance is that current in vitro assays do not accurately replicate the range of physiological conditions. Animal scientists have long sought to predict protein and amino acid digestibility for precision nutrition. Monogastric production animals, especially swine, have gastrointestinal systems similar to humans, and evaluating potential allergen digestibility in this context may be beneficial. Currently, there is no compelling evidence that the mechanisms sometimes postulated to be associated with allergenic sensitization, e.g. antacid modification of stomach pH, are valid among production animals. Furthermore, examples are provided where non-biologically representative assays are better at predicting protein and amino acid digestibility compared with those designed to mimic in vivo conditions. Greater emphasis should be made to align in vitro assessments with in vivo data. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

  11. Fresh water green microalga Scenedesmus abundans: A potential feedstock for high quality biodiesel production.

    PubMed

    Mandotra, S K; Kumar, Pankaj; Suseela, M R; Ramteke, P W

    2014-03-01

    Present investigation studied the potential of fresh water green microalga Scenedesmus abundans as a feedstock for biodiesel production. To study the biomass and lipid yield, the culture was grown in BBM, Modified CHU-13 and BG-11 medium. Among the tested nitrogen concentration using Modified CHU-13 medium, the highest biomass and lipid yield of 1.113±0.05g/L and 489±23mg/L respectively was found in the culture medium with 0.32g/L of nitrogen (KNO3). Different lipid extraction as well as transesterification methods were also tested. Fatty acid profile of alga grown in large scale indigenous made photobioreactor has shown abundance of fatty acids with carbon chain length of C16 and C18. Various biodiesel properties such as cetane number, iodine value and saponification value were found to be in accordance with Brazilian National Petroleum Agency (ANP255) and European biodiesel standard EN14214 which makes S. abundans as a potential feedstock for biodiesel production. Copyright © 2014 Elsevier Ltd. All rights reserved.

  12. 40 CFR 721.9484 - Dimer acid/rosin amidoamine reaction product (generic).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Dimer acid/rosin amidoamine reaction... Specific Chemical Substances § 721.9484 Dimer acid/rosin amidoamine reaction product (generic). (a... generically as Dimer acid/rosin amidoamine reaction product (PMN P-99-0143) is subject to reporting under this...

  13. 40 CFR 721.9484 - Dimer acid/rosin amidoamine reaction product (generic).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Dimer acid/rosin amidoamine reaction... Specific Chemical Substances § 721.9484 Dimer acid/rosin amidoamine reaction product (generic). (a... generically as Dimer acid/rosin amidoamine reaction product (PMN P-99-0143) is subject to reporting under this...

  14. Hematite Core Nanoparticles with Carbon Shell: Potential for Environmentally Friendly Production from Iron Mining Sludge

    NASA Astrophysics Data System (ADS)

    Stević, Dragana; Mihajlović, Dijana; Kukobat, Radovan; Hattori, Yoshiyuki; Sagisaka, Kento; Kaneko, Katsumi; Atlagić, Suzana Gotovac

    2016-08-01

    Hematite nanoparticles with amorphous, yet relatively uniform carbon shell, were produced based exclusively on the waste sludge from the iron mine as the raw material. The procedure for acid digestion-based purification of the sludge with the full recovery of acid vapors and the remaining non-toxic rubble is described. Synthesis of the hematite nanoparticles was performed by the arrested precipitation method with cationic surfactant. The particles were thoroughly characterized and the potential of their economical production for the battery industry is indicated.

  15. Screening and characterization of Isochrysis strains and optimization of culture conditions for docosahexaenoic acid production.

    PubMed

    Liu, Jin; Sommerfeld, Milton; Hu, Qiang

    2013-06-01

    Isochrysis is a genus of marine unicellular microalgae that produces docosahexaenoic acid (DHA, C22:6), a very long chain polyunsaturated fatty acid (PUFA) of significant health and nutritional value. Mass cultivation of Isochrysis for DHA production for human consumption has not been established due to disappointing low DHA productivity obtained from commonly used Isochrysis strains. In this study, 19 natural Isochrysis strains were screened for DHA yields and the results showed that the cellular DHA content ranged from 6.8 to 17.0 % of total fatty acids with the highest DHA content occurring in the exponential growth phase. Isochrysis galbana #153180 exhibited the greatest DHA production potential and was selected for further investigation. The effects of different light intensities, forms, and concentrations of nitrogen, phosphorus, and salinity on growth and DHA production of I. galbana #153180 were studied in a bubble column photobioreactor (PBR). Under favorable culture conditions, I. galbana #153180 contained DHA up to 17.5 % of total fatty acids or 1.7 % of cell dry weight. I. galbana #153180 was further tested in outdoor flat-plate PBRs varying in light path length, starting cell density (SCD), and culture mode (batch versus semicontinuous). When optimized, record high biomass and DHA productivity of I. galbana #153180 of 0.72 g L(-1) day(-1) and 13.6 mg L(-1) day(-1), or 26.4 g m(-2) day(-1) and 547.7 mg m(-2) day(-1), respectively, were obtained, suggesting that I. galbana #153180 may be a desirable strain for commercial production of DHA.

  16. Acidic organic compounds in beverage, food, and feed production.

    PubMed

    Quitmann, Hendrich; Fan, Rong; Czermak, Peter

    2014-01-01

    Organic acids and their derivatives are frequently used in beverage, food, and feed production. Acidic additives may act as buffers to regulate acidity, antioxidants, preservatives, flavor enhancers, and sequestrants. Beneficial effects on animal health and growth performance have been observed when using acidic substances as feed additives. Organic acids could be classified in groups according to their chemical structure. Each group of organic acids has its own specific properties and is used for different applications. Organic acids with low molecular weight (e.g. acetic acid, lactic acid, and citric acid), which are part of the primary metabolism, are often produced by fermentation. Others are produced more economically by chemical synthesis based on petrochemical raw materials on an industrial scale (e.g. formic acid, propionic and benzoic acid). Biotechnology-based production is of interest due to legislation, consumer demand for natural ingredients, and increasing environmental awareness. In the United States, for example, biocatalytically produced esters for food applications can be labeled as "natural," whereas identical conventional acid catalyst-based molecules cannot. Natural esters command a price several times that of non-natural esters. Biotechnological routes need to be optimized regarding raw materials and yield, microorganisms, and recovery methods. New bioprocesses are being developed for organic acids, which are at this time commercially produced by chemical synthesis. Moreover, new organic acids that could be produced with biotechnological methods are under investigation for food applications.

  17. Lipase-catalyzed production of short-chain acids terpenyl esters of interest to the food industry.

    PubMed

    Laboret, F; Perraud, R

    1999-12-01

    The production of low molecular weight esters as flavor compounds by biotechnological processes has a potential interest for the food industry. The use of natural available substrates and enzymes is an essential part of the process design, because the products may obtain natural label. In this study, direct esterification of citronellol and geraniol with short-chain fatty acids catalyzed by free lipase from Mucor miehei was performed with high yields in n-hexane. The effects of the acid:alcohol ratio on the bioconversion rate of increasing chain length esters was investigated. To reach the optimum yield, substrates and enzyme concentration were determined. The inhibiting effects of acid are strongly attenuated by reducing the quantity of acid and increasing the amount of enzyme in media following the optimum values. Improvements have been made to increase the ester purity. The consumption of excess substrate by adding calculated amounts of acid gives a 10% yield enhancement, and leads to 100% pure terpenyl esters. The first steps to a scale-up application were attempted using a reactor that allowed us to produce ester quantities up to 100 cm3. Separation and purification of the products were treated with success, underlining the lipase stability and efficiency under the conditions of this study. The ability to recover the enzyme, and reusing it in bioconversions, plays a major role in reducing the cost of the overall process.

  18. Hyper-thermal acid hydrolysis and adsorption treatment of red seaweed, Gelidium amansii for butyric acid production with pH control.

    PubMed

    Ra, Chae Hun; Jeong, Gwi-Taek; Kim, Sung-Koo

    2017-03-01

    Optimal hyper-thermal (HT) acid hydrolysis conditions for Gelidium amansii were determined to be 12% (w/v) seaweed slurry content and 144 mM H 2 SO 4 at 150 °C for 10 min. HT acid hydrolysis-treated G. amansii hydrolysates produced low concentrations of inhibitory compounds and adsorption treatment using 3% activated carbon. An adsorption time of 5 min was subsequently used to remove the inhibitory 5-hydroxymethylfurfural from the medium. A final maximum monosaccharide concentration of 44.6 g/L and 79.1% conversion from 56.4 g/L total fermentable monosaccharides with 120 g dw/L G. amansii slurry was obtained from HT acid hydrolysis, enzymatic saccharification, and adsorption treatment. This study demonstrates the potential for butyric acid production from G. amansii hydrolysates under non-pH-controlled as well as pH-controlled fermentation using Clostridium acetobutylicum KCTC 1790. The activated carbon treatment and pH-controlled fermentation showed synergistic effects and produced butyric acid at a concentration of 11.2 g/L after 9 days of fermentation.

  19. EPS production by Propionibacterium freudenreichii facilitates its immobilization for propionic acid production.

    PubMed

    Belgrano, F D S; Verçoza, B R F; Rodrigues, J C F; Hatti-Kaul, R; Pereira, N

    2018-04-28

    Immobilization of microbial cells is a useful strategy for developing high cell density bioreactors with improved stability and productivity for production of different chemicals. Functionalization of the immobilization matrix or biofilm forming property of some strains has been utilized for achieving cell attachment. The aim of the present study was to investigate the production of exopolysaccharide (EPS) by Propionibacterium freudenreichii C.I.P 59.32 and utilize this feature for immobilization of the cells on porous glass beads for production of propionic acid. Propionibacterium freudenreichii was shown to produce both capsular and excreted EPS during batch cultivations using glucose as carbon source. Different electron microscopy techniques confirmed the secretion of EPS and formation of cellular aggregates. The excreted EPS was mainly composed of mannose and glucose in a 5·3 : 1 g g -1 ratio. Immobilization of the cells on untreated and polyethyleneimine (PEI)-treated Poraver beads in a bioreactor was evaluated. Higher productivity and yield of propionic acid (0·566 g l -1  h -1 and 0·314 g g -1 , respectively) was achieved using cells immobilized to untreated beads and EPS production reached 617·5 mg l -1 after 48 h. These results suggest an important role of EPS-producing strains for improving cell immobilization and propionic acid production. This study demonstrates the EPS-producing microbe to be easily immobilized on a solid matrix and to be used in a bioprocess. Such a system could be optimized for achieving high cell density in fermentations without the need for functionalization of the matrix. © 2018 The Society for Applied Microbiology.

  20. Decoupling Hydrogen and Oxygen Production in Acidic Water Electrolysis Using a Polytriphenylamine-Based Battery Electrode.

    PubMed

    Ma, Yuanyuan; Dong, Xiaoli; Wang, Yonggang; Xia, Yongyao

    2018-03-05

    Hydrogen production through water splitting is considered a promising approach for solar energy harvesting. However, the variable and intermittent nature of solar energy and the co-production of H 2 and O 2 significantly reduce the flexibility of this approach, increasing the costs of its use in practical applications. Herein, using the reversible n-type doping/de-doping reaction of the solid-state polytriphenylamine-based battery electrode, we decouple the H 2 and O 2 production in acid water electrolysis. In this architecture, the H 2 and O 2 production occur at different times, which eliminates the issue of gas mixing and adapts to the variable and intermittent nature of solar energy, facilitating the conversion of solar energy to hydrogen (STH). Furthermore, for the first time, we demonstrate a membrane-free solar water splitting through commercial photovoltaics and the decoupled acid water electrolysis, which potentially paves the way for a new approach for solar water splitting. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  1. Calyx diversity of flavonols and fatty acids in Roselle (Hibiscus sabdariffa) for use as a potential nutraceutical crop.

    USDA-ARS?s Scientific Manuscript database

    Flavonols and fatty acids in plants has potential to be used as an antioxidant, lowering of cholesterol, and for cancer prevention. Roselle is a photoperiod and frost-sensitive species requiring greenhouse production in the Griffin, GA environment. Six accessions of roselle calyces were evaluated fo...

  2. Combinatorial Effects of Fatty Acid Elongase Enzymes on Nervonic Acid Production in Camelina sativa

    PubMed Central

    Huai, Dongxin; Zhang, Yuanyuan; Zhang, Chunyu; Cahoon, Edgar B.; Zhou, Yongming

    2015-01-01

    Very long chain fatty acids (VLCFAs) with chain lengths of 20 carbons and longer provide feedstocks for various applications; therefore, improvement of VLCFA contents in seeds has become an important goal for oilseed enhancement. VLCFA biosynthesis is controlled by a multi-enzyme protein complex referred to as fatty acid elongase, which is composed of β-ketoacyl-CoA synthase (KCS), β-ketoacyl-CoA reductase (KCR), β-hydroxyacyl-CoA dehydratase (HCD) and enoyl reductase (ECR). KCS has been identified as the rate-limiting enzyme, but little is known about the involvement of other three enzymes in VLCFA production. Here, the combinatorial effects of fatty acid elongase enzymes on VLCFA production were assessed by evaluating the changes in nervonic acid content. A KCS gene from Lunaria annua (LaKCS) and the other three elongase genes from Arabidopsis thaliana were used for the assessment. Five seed-specific expressing constructs, including LaKCS alone, LaKCS with AtKCR, LaKCS with AtHCD, LaKCS with AtECR, and LaKCS with AtKCR and AtHCD, were transformed into Camelina sativa. The nervonic acid content in seed oil increased from null in wild type camelina to 6-12% in LaKCS-expressing lines. However, compared with that from the LaKCS-expressing lines, nervonic acid content in mature seeds from the co-expressing lines with one or two extra elongase genes did not show further increases. Nervonic acid content from LaKCS, AtKCR and AtHCD co-expressing line was significantly higher than that in LaKCS-expressing line during early seed development stage, while the ultimate nervonic acid content was not significantly altered. The results from this study thus provide useful information for future engineering of oilseed crops for higher VLCFA production. PMID:26121034

  3. Potential of biohydrogen production from effluents of citrus processing industry using anaerobic bacteria from sewage sludge.

    PubMed

    Torquato, Lilian D M; Pachiega, Renan; Crespi, Marisa S; Nespeca, Maurílio Gustavo; de Oliveira, José Eduardo; Maintinguer, Sandra I

    2017-01-01

    Citrus crops are among the most abundant crops in the world, which processing is mainly based on juice extraction, generating large amounts of effluents with properties that turn them into potential pollution sources if they are improperly discarded. This study evaluated the potential for bioconversion of effluents from citrus-processing industry (wastewater and vinasse) into hydrogen through the dark fermentation process, by applying anaerobic sewage sludge as inoculum. The inoculum was previously heat treated to eliminate H 2 -consumers microorganisms and improve its activity. Anaerobic batch reactors were operated in triplicate with increasing proportions (50, 80 and 100%) of each effluent as substrate at 37°C, pH 5.5. Citrus effluents had different effects on inoculum growth and H 2 yields, demonstrated by profiles of acetic acid, butyric acid, propionic acid and ethanol, the main by-products generated. It was verified that there was an increase in the production of biogas with the additions of either wastewater (7.3, 33.4 and 85.3mmolL -1 ) or vinasse (8.8, 12.7 and 13.4mmolL -1 ) in substrate. These effluents demonstrated remarkable energetic reuse perspectives: 24.0MJm -3 and 4.0MJm -3 , respectively. Besides promoting the integrated management and mitigation of anaerobic sludge and effluents from citrus industry, the biohydrogen production may be an alternative for the local energy supply, reducing the operational costs in their own facilities, while enabling a better utilization of the biological potential contained in sewage sludges. Copyright © 2016 Elsevier Ltd. All rights reserved.

  4. Improving succinic acid production by Actinobacillus succinogenes from raw industrial carob pods.

    PubMed

    Carvalho, Margarida; Roca, Christophe; Reis, Maria A M

    2016-10-01

    Carob pods are an inexpensive by-product of locust bean gum industry that can be used as renewable feedstock for bio-based succinic acid. Here, for the first time, unprocessed raw carob pods were used to extract a highly enriched sugar solution, afterwards used as substrate to produce succinic acid using Actinobacillus succinogenes. Batch fermentations containing 30g/L sugars resulted in a production rate of 1.67gSA/L.h and a yield of 0.39gSA/g sugars. Taking advantage of A. succinogenes' metabolism, uncoupling cell growth from succinic acid production, a fed-batch mode was implemented to increase succinic acid yield and reduce by-products formation. This strategy resulted in a succinic acid yield of 0.94gSA/g sugars, the highest yield reported in the literature for fed-batch and continuous experiments, while maintaining by-products at residual values. Results demonstrate that raw carob pods are a highly efficient feedstock for bio-based succinic acid production. Copyright © 2016 Elsevier Ltd. All rights reserved.

  5. Enzyme immunoassay for tenuazonic acid in apple and tomato products.

    PubMed

    Gross, Madeleine; Curtui, Valeriu; Ackermann, Yvonne; Latif, Hadri; Usleber, Ewald

    2011-12-14

    The Alternaria mycotoxin tenuazonic acid was derivatized with succinic anhydride and conjugated to keyhole limpet hemocyanin (KLH) and to horseradish peroxidase (HRP), respectively. The KLH conjugate was used to produce polyclonal antibodies in rabbits. A competitive direct enzyme immunoassay (EIA) for tenuazonic acid was established, which was moderately sensitive for tenuazonic acid [50% inhibition concentration (IC(50)): 320 ± 130 ng/mL] but strongly reacted with tenuazonic acid acetate (IC(50): 23.3 ± 7.5 ng/mL). Therefore, an optimized EIA protocol was established, which employed acetylation of standard and sample extract solutions. The mean standard curve detection limit (IC(30)) for tenuazonic acid acetate was 5.4 ± 2.0 ng/mL, enabling detection limits for tenuazonic acid in apple and tomato products of 25-50 ng/g (150 ng/g in tomato paste). Recoveries in a concentration range of 50-2000 ng/g were 60-130% in apple juice and tomato juice and 40-150% in other tomato products. Tenuazonic acid was detected in apple juice and tomato products from German retail shops at levels of 50-200 ng/g. In conclusion, this novel EIA for tenuazonic acid could be useful within a screening program for Alternaria mycotoxins in food.

  6. Metabolic engineering in the biotechnological production of organic acids in the tricarboxylic acid cycle of microorganisms: Advances and prospects.

    PubMed

    Yin, Xian; Li, Jianghua; Shin, Hyun-Dong; Du, Guocheng; Liu, Long; Chen, Jian

    2015-11-01

    Organic acids, which are chemically synthesized, are also natural intermediates in the metabolic pathways of microorganisms, among which the tricarboxylic acid (TCA) cycle is the most crucial route existing in almost all living organisms. Organic acids in the TCA cycle include citric acid, α-ketoglutaric acid, succinic acid, fumaric acid, l-malic acid, and oxaloacetate, which are building-block chemicals with wide applications and huge markets. In this review, we summarize the synthesis pathways of these organic acids and review recent advances in metabolic engineering strategies that enhance organic acid production. We also propose further improvements for the production of organic acids with systems and synthetic biology-guided metabolic engineering strategies. Copyright © 2015 Elsevier Inc. All rights reserved.

  7. Anaerobic Fermentation for Production of Carboxylic Acids as Bulk Chemicals from Renewable Biomass.

    PubMed

    Wang, Jufang; Lin, Meng; Xu, Mengmeng; Yang, Shang-Tian

    Biomass represents an abundant carbon-neutral renewable resource which can be converted to bulk chemicals to replace petrochemicals. Carboxylic acids have wide applications in the chemical, food, and pharmaceutical industries. This chapter provides an overview of recent advances and challenges in the industrial production of various types of carboxylic acids, including short-chain fatty acids (acetic, propionic, butyric), hydroxy acids (lactic, 3-hydroxypropionic), dicarboxylic acids (succinic, malic, fumaric, itaconic, adipic, muconic, glucaric), and others (acrylic, citric, gluconic, pyruvic) by anaerobic fermentation. For economic production of these carboxylic acids as bulk chemicals, the fermentation process must have a sufficiently high product titer, productivity and yield, and low impurity acid byproducts to compete with their petrochemical counterparts. System metabolic engineering offers the tools needed to develop novel strains that can meet these process requirements for converting biomass feedstock to the desirable product.

  8. High titer L-lactic acid production from corn stover with minimum wastewater generation and techno-economic evaluation based on Aspen plus modeling.

    PubMed

    Liu, Gang; Sun, Jiaoe; Zhang, Jian; Tu, Yi; Bao, Jie

    2015-12-01

    Technological potentials of l-lactic acid production from corn stover feedstock were investigated by experimental and techno-economic studies. An optimal performance with 104.5 g/L in l-lactic acid titer and 71.5% in overall yield from cellulose in corn stover to l-lactic acid using an engineered Pediococcus acidilactici strain were obtained by overcoming several technical barriers. A rigorous Aspen plus model for l-lactic acid production starting from dry dilute acid pretreated and biodetoxified corn stover was developed. The techno-economic analysis shows that the minimum l-lactic acid selling price (MLSP) was $0.523 per kg, which was close to that of the commercial l-lactic acid produced from starch feedstock, and 24% less expensive than that of ethanol from corn stover, even though the xylose utilization was not considered. The study provided a prototype of industrial application and an evaluation model for high titer l-lactic acid production from lignocellulose feedstock. Copyright © 2015 Elsevier Ltd. All rights reserved.

  9. Production of eicosapentaenoic acid by high cell density cultivation of the marine oleaginous diatom Fistulifera solaris.

    PubMed

    Tanaka, Tsuyoshi; Yabuuchi, Takashi; Maeda, Yoshiaki; Nojima, Daisuke; Matsumoto, Mitsufumi; Yoshino, Tomoko

    2017-12-01

    Polyunsaturated fatty acids (PUFAs), including eicosapentaenoic acid (EPA), have attracted attention owing to their health benefits for humans, as well as their importance in aquaculture and animal husbandry. Establishing a sustainable PUFA supply based on fish oils has been difficult due to their increasing demand. Therefore, alternative sources of PUFAs are required. In this research, we examined the potential of the marine oleaginous diatom Fistulifera solaris as an alternative producer of PUFAs. Optimization of culture conditions was carried out for high cell density cultivation, and a maximal biomass productivity of 1.32±0.13g/(L·day) was achieved. By slightly adjusting the culture conditions for EPA production, the maximal EPA productivity reached 135.7±10.0mg/(L·day). To the best of our knowledge, this is the highest EPA productivity among microalgae cultured under photoautotrophic conditions. This result indicates that F. solaris is a promising candidate host for sustainable PUFA production. Copyright © 2017 Elsevier Ltd. All rights reserved.

  10. Differences in Pop Levels between Conventional and Omega-3 Fatty Acid-Enriched Milk and Dairy Products

    PubMed Central

    Guerranti, Cristiana; Focardi, Silvano Ettore

    2011-01-01

    Conventional and omega-3 fatty acid-enriched milk and cheese were analyzed for persistent organic pollutants (POPs). Omega-3-enriched products are usually supplemented with fish oil which is potentially contaminated. All classes of the considered POPs (PCBs, DDT, HCB, PBDEs, and PCDD/Fs) were found in the samples, with average concentrations higher in omega-3-enriched products than in conventional ones. For PCBs, DDT, and HCB, differences were statistically significant and, therefore, cannot be ascribed to normal variability. With regard to all classes of compounds, the highest levels in individual samples were always found in omega-3 products, in line with the hypothesis that these foods are potentially more contaminated than conventional ones. PMID:23724286

  11. 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.

  12. Effects of cultivar, fruit number and reflected photosynthetically active radiation on Fragaria x ananassa productivity and fruit ellagic acid and ascorbic acid concentrations.

    PubMed

    Atkinson, C J; Dodds, P A A; Ford, Y Y; Le Mière, J; Taylor, J M; Blake, P S; Paul, N

    2006-03-01

    A number of strawberry varieties were surveyed for their total ellagic acid concentration, and attempts were made to determine if ellagic acid and ascorbic acid concentrations of two strawberry cultivars could be increased by polythene reflective mulches. After adjusting crop yields and cultivation using polythene mulches with two different PAR reflective capacities, field- and polytunnel-grown strawberries were analysed for ellagic acid and ascorbic acid concentrations by HPLC. Comparative measurements of yield and fruit quality were determined along with plant developmental changes. Ellagic acid concentration varied widely with strawberry cultivar (60-341 microg g(-1) frozen weight), as did the ratio of conjugated ellagic acid : free ellagic acid. Also, there was significant year-to-year variation in total ellagic acid concentration with some cultivars. Mulches with different reflective capacities impacted on strawberry production; highly reflective mulches significantly increased growth and yield, the latter due to increases in fruit size and number. Highly reflective mulches significantly increased total concentrations of ellagic acid and ascorbic acid relative to control in fruit of different cultivars. The potential of agronomic practices to enhance the concentration and amounts of these important dietary bioactive compounds is discussed.

  13. Production of Fumaric Acid in 20-Liter Fermentors

    PubMed Central

    Rhodes, R. A.; Lagoda, A. A.; Misenheimer, T. J.; Smith, M. L.; Anderson, R. F.; Jackson, R. W.

    1962-01-01

    The conditions necessary for the production of fumaric acid in 20-liter fermentors by fermentation of glucose with Rhizopus arrhizus strain NRRL 2582 were determined. Continuous neutralization of fumaric acid was necessary for optimal yields. Yields of the calcium salt were in excess of 65 g of fumaric acid from 100 g of sugar consumed during fermentation of sugar concentrations of 10 to 16%. Conditions established for calcium fumarate production include a simple mineral salts medium, 0.5 v:v:min aeration rate, 300 rev/min agitation rate in a baffled tank, 33 C incubation temperature, CaCO3 to neutralize the acid formed, and a 4 to 5% (v/v) vegetative inoculum. A suitable procedure and medium for the preparation of a vigorous vegetative inoculum were established. The tendency for calcium fumarate fermentations to foam excessively was controlled with a proper antifoam agent added prior to sterilization of the medium and again at daily intervals during fermentation. The production of soluble sodium or potassium fumarates was inhibited when the concentration of fumarates reached 3.5 to 4.0%. No means of overcoming this inhibition was found. Starches and certain other grain-derived carbohydrates were fermented to form calcium fumarate in flask experiments with approximately the same efficiency as was glucose. PMID:16349614

  14. Batch and fed-batch production of butyric acid by Clostridium butyricum ZJUCB

    PubMed Central

    He, Guo-qing; Kong, Qing; Chen, Qi-he; Ruan, Hui

    2005-01-01

    The production of butyric acid by Clostridium butyricum ZJUCB at various pH values was investigated. In order to study the effect of pH on cell growth, butyric acid biosynthesis and reducing sugar consumption, different cultivation pH values ranging from 6.0 to 7.5 were evaluated in 5-L bioreactor. In controlled pH batch fermentation, the optimum pH for cell growth and butyric acid production was 6.5 with a cell yield of 3.65 g/L and butyric acid yield of 12.25 g/L. Based on these results, this study then compared batch and fed-batch fermentation of butyric acid production at pH 6.5. Maximum value (16.74 g/L) of butyric acid concentration was obtained in fed-batch fermentation compared to 12.25 g/L in batch fermentation. It was concluded that cultivation under fed-batch fermentation mode could enhance butyric acid production significantly (P<0.01) by C. butyricum ZJUCB. PMID:16252341

  15. Reduced carbon sequestration potential of biochar in acidic soil.

    PubMed

    Sheng, Yaqi; Zhan, Yu; Zhu, Lizhong

    2016-12-01

    Biochar application in soil has been proposed as a promising method for carbon sequestration. While factors affecting its carbon sequestration potential have been widely investigated, the number of studies on the effect of soil pH is limited. To investigate the carbon sequestration potential of biochar across a series of soil pH levels, the total carbon emission, CO 2 release from inorganic carbon, and phospholipid fatty acids (PLFAs) of six soils with various pH levels were compared after the addition of straw biochar produced at different pyrolysis temperatures. The results show that the acidic soils released more CO 2 (1.5-3.5 times higher than the control) after the application of biochar compared with neutral and alkaline soils. The degradation of both native soil organic carbon (SOC) and biochar were accelerated. More inorganic CO 2 release in acidic soil contributed to the increased degradation of biochar. Higher proportion of gram-positive bacteria in acidic soil (25%-36%) was responsible for the enhanced biochar degradation and simultaneously co-metabolism of SOC. In addition, lower substrate limitation for bacteria, indicated by higher C-O stretching after the biochar application in the acidic soil, also caused more CO 2 release. In addition to the soil pH, other factors such as clay contents and experimental duration also affected the phsico-chemical and biotic processes of SOC dynamics. Gram-negative/gram-positive bacteria ratio was found to be negatively related to priming effects, and suggested to serve as an indicator for priming effect. In general, the carbon sequestration potential of rice-straw biochar in soil reduced along with the decrease of soil pH especially in a short-term. Given wide spread of acidic soils in China, carbon sequestration potential of biochar may be overestimated without taking into account the impact of soil pH. Copyright © 2016 Elsevier B.V. All rights reserved.

  16. Recycling stabilised/solidified drill cuttings for forage production in acidic soils.

    PubMed

    Kogbara, Reginald B; Dumkhana, Bernard B; Ayotamuno, Josiah M; Okparanma, Reuben N

    2017-10-01

    Stabilisation/solidification (S/S), which involves fixation and immobilisation of contaminants using cementitious materials, is one method of treating drill cuttings before final fate. This work considers reuse of stabilised/solidified drill cuttings for forage production in acidic soils. It sought to improve the sustainability of S/S technique through supplementation with the phytoremediation potential of plants, eliminate the need for landfill disposal and reduce soil acidity for better plant growth. Drill cuttings with an initial total petroleum hydrocarbon (TPH) concentration of 17,125 mg kg -1 and low concentrations of metals were treated with 5%, 10%, and 20% cement dosages. The treated drill cuttings were reused in granular form for growing a forage, elephant grass (Pennisetum purpureum), after mixing with uncontaminated soil. The grasses were also grown in uncontaminated soil. The phytoremediation and growth potential of the plants was assessed over a 12-week period. A mix ratio of one part drill cuttings to three parts uncontaminated soil was required for active plant growth. The phytoremediation ability of elephant grass (alongside abiotic losses) reduced the TPH level (up to 8795 mg kg -1 ) in the soil-treated-drill cuttings mixtures below regulatory (1000 mg kg -1 ) levels. There were also decreased concentrations of metals. The grass showed better heights and leaf lengths in soil containing drill cuttings treated with 5% cement dosage than in uncontaminated soil. The results suggest that recycling S/S treated drill cuttings for forage production may be a potential end use of the treated waste. Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. Enhancing Fatty Acid Production of Saccharomyces cerevisiae as an Animal Feed Supplement.

    PubMed

    You, Seung Kyou; Joo, Young-Chul; Kang, Dae Hee; Shin, Sang Kyu; Hyeon, Jeong Eun; Woo, Han Min; Um, Youngsoon; Park, Chulhwan; Han, Sung Ok

    2017-12-20

    Saccharomyces cerevisiae is used for edible purposes, such as human food or as an animal feed supplement. Fatty acids are also beneficial as feed supplements, but S. cerevisiae produces small amounts of fatty acids. In this study, we enhanced fatty acid production of S. cerevisiae by overexpressing acetyl-CoA carboxylase, thioesterase, and malic enzyme associated with fatty acid metabolism. The enhanced strain pAMT showed 2.4-fold higher fatty acids than the wild-type strain. To further increase the fatty acids, various nitrogen sources were analyzed and calcium nitrate was selected as an optimal nitrogen source for fatty acid production. By concentration optimization, 672 mg/L of fatty acids was produced, which was 4.7-fold higher than wild-type strain. These results complement the low level fatty acid production and make it possible to obtain the benefits of fatty acids as an animal feed supplement while, simultaneously, maintaining the advantages of S. cerevisiae.

  18. Potential applications of antimicrobial fatty acids in medicine, agriculture and other industries.

    PubMed

    Desbois, Andrew P

    2012-08-01

    The antimicrobial effects of free fatty acids are well recognised and these compounds can prevent the growth of or directly kill bacteria, fungi and other microbes by affecting multiple cellular targets, including the cell membrane and components found therein. Moreover, fatty acids exert detrimental effects on microbial pathogens by interfering with mechanisms of virulence, such as preventing biofilm formation and inhibiting the production of toxins and enzymes. The antimicrobial properties of free fatty acids can be exploited for the preservation of perishable products, such as food and cosmetics, and for the prevention and treatment of infections. These safe natural products are particularly useful in circumstances where antimicrobial activity is required but where the use of conventional antibiotics is undesirable or forbidden. This review focuses on the most promising prospects for exploiting the antimicrobial properties of free fatty acids for applications in various industries. The benefits of using fatty acids as antimicrobial agents are discussed and relevant recent patents are highlighted.

  19. Production of bioactive substances by intestinal bacteria as a basis for explaining probiotic mechanisms: bacteriocins and conjugated linoleic acid.

    PubMed

    O'Shea, Eileen F; Cotter, Paul D; Stanton, Catherine; Ross, R Paul; Hill, Colin

    2012-01-16

    The mechanisms by which intestinal bacteria achieve their associated health benefits can be complex and multifaceted. In this respect, the diverse microbial composition of the human gastrointestinal tract (GIT) provides an almost unlimited potential source of bioactive substances (pharmabiotics) which can directly or indirectly affect human health. Bacteriocins and fatty acids are just two examples of pharmabiotic substances which may contribute to probiotic functionality within the mammalian GIT. Bacteriocin production is believed to confer producing strains with a competitive advantage within complex microbial environments as a consequence of their associated antimicrobial activity. This has the potential to enable the establishment and prevalence of producing strains as well as directly inhibiting pathogens within the GIT. Consequently, these antimicrobial peptides and the associated intestinal producing strains may be exploited to beneficially influence microbial populations. Intestinal bacteria are also known to produce a diverse array of health-promoting fatty acids. Indeed, certain strains of intestinal bifidobacteria have been shown to produce conjugated linoleic acid (CLA), a fatty acid which has been associated with a variety of systemic health-promoting effects. Recently, the ability to modulate the fatty acid composition of the liver and adipose tissue of the host upon oral administration of CLA-producing bifidobacteria and lactobacilli was demonstrated in a murine model. Importantly, this implies a potential therapeutic role for probiotics in the treatment of certain metabolic and immunoinflammatory disorders. Such examples serve to highlight the potential contribution of pharmabiotic production to probiotic functionality in relation to human health maintenance. Copyright © 2011 Elsevier B.V. All rights reserved.

  20. Metabolic Engineering for Enhanced Medium Chain Omega Hydroxy Fatty Acid Production in Escherichia coli

    PubMed Central

    Xiao, Kang; Yue, Xiu-Hong; Chen, Wen-Chao; Zhou, Xue-Rong; Wang, Lian; Xu, Lin; Huang, Feng-Hong; Wan, Xia

    2018-01-01

    Medium chain hydroxy fatty acids (HFAs) at ω-1, 2, or 3 positions (ω-1/2/3) are rare in nature but are attractive due to their potential applications in industry. They can be metabolically engineered in Escherichia coli, however, the current yield is low. In this study, metabolic engineering with P450BM3 monooxygenase was applied to regulate both the chain length and sub-terminal position of HFA products in E. coli, leading to increased yield. Five acyl-acyl carrier protein thioesterases from plants and bacteria were first evaluated for regulating the chain length of fatty acids. Co-expression of the selected thioesterase gene CcFatB1 with a fatty acid metabolism regulator fadR and monooxygenase P450BM3 boosted the production of HFAs especially ω-3-OH-C14:1, in both the wild type and fadD deficient strain. Supplementing renewable glycerol to reduce the usage of glucose as a carbon source further increased the HFAs production to 144 mg/L, representing the highest titer of such HFAs obtained in E. coli under the comparable conditions. This study illustrated an improved metabolic strategy for medium chain ω-1/2/3 HFAs production in E. coli. In addition, the produced HFAs were mostly secreted into culture media, which eased its recovery. PMID:29467747

  1. Effects of abscisic acid, gibberellin, ethylene and their interactions on production of phenolic acids in salvia miltiorrhiza bunge hairy roots.

    PubMed

    Liang, Zongsuo; Ma, Yini; Xu, Tao; Cui, Beimi; Liu, Yan; Guo, Zhixin; Yang, Dongfeng

    2013-01-01

    Salvia miltiorrhiza is one of the most important traditional Chinese medicinal plants because of its excellent performance in treating coronary heart disease. Phenolic acids mainly including caffeic acid, rosmarinic acid and salvianolic acid B are a group of active ingredients in S. miltiorrhiza. Abscisic acid (ABA), gibberellin (GA) and ethylene are three important phytohormones. In this study, effects of the three phytohormones and their interactions on phenolic production in S. miltiorrhiza hairy roots were investigated. The results showed that ABA, GA and ethylene were all effective to induce production of phenolic acids and increase activities of PAL and TAT in S. miltiorrhiza hairy roots. Effects of phytohormones were reversed by their biosynthetic inhibitors. Antagonistic actions between the three phytohormones played important roles in the biosynthesis of phenolic acids. GA signaling is necessary for ABA and ethylene-induced phenolic production. Yet, ABA and ethylene signaling is probably not necessary for GA3-induced phenolic production. The complex interactions of phytohormones help us reveal regulation mechanism of secondary metabolism and scale-up production of active ingredients in plants.

  2. Effects of Abscisic Acid, Gibberellin, Ethylene and Their Interactions on Production of Phenolic Acids in Salvia miltiorrhiza Bunge Hairy Roots

    PubMed Central

    Xu, Tao; Cui, Beimi; Liu, Yan; Guo, Zhixin; Yang, Dongfeng

    2013-01-01

    Salvia miltiorrhiza is one of the most important traditional Chinese medicinal plants because of its excellent performance in treating coronary heart disease. Phenolic acids mainly including caffeic acid, rosmarinic acid and salvianolic acid B are a group of active ingredients in S. miltiorrhiza. Abscisic acid (ABA), gibberellin (GA) and ethylene are three important phytohormones. In this study, effects of the three phytohormones and their interactions on phenolic production in S. miltiorrhiza hairy roots were investigated. The results showed that ABA, GA and ethylene were all effective to induce production of phenolic acids and increase activities of PAL and TAT in S. miltiorrhiza hairy roots. Effects of phytohormones were reversed by their biosynthetic inhibitors. Antagonistic actions between the three phytohormones played important roles in the biosynthesis of phenolic acids. GA signaling is necessary for ABA and ethylene-induced phenolic production. Yet, ABA and ethylene signaling is probably not necessary for GA3-induced phenolic production. The complex interactions of phytohormones help us reveal regulation mechanism of secondary metabolism and scale-up production of active ingredients in plants. PMID:24023778

  3. Acid production in dental plaque after exposure to probiotic bacteria

    PubMed Central

    2012-01-01

    Background The increasing interest in probiotic lactobacilli in health maintenance has raised the question of potential risks. One possible side effect could be an increased acidogenicity in dental plaque. The aim of this study was to investigate the effect of probiotic lactobacilli on plaque lactic acid (LA) production in vitro and in vivo. Methods In the first part (A), suspensions of two lactobacilli strains (L. reuteri DSM 17938, L. plantarum 299v) were added to suspensions of supragingival dental plaque collected from healthy young adults (n=25). LA production after fermentation with either xylitol or fructose was analyzed. In the second part (B), subjects (n=18) were given lozenges with probiotic lactobacilli (L. reuteri DSM 17938 and ATCC PTA 5289) or placebo for two weeks in a double-blinded, randomized cross-over trial. The concentration of LA in supragingival plaque samples was determined at baseline and after 2 weeks. Salivary counts of mutans streptococci (MS) and lactobacilli were estimated with chair-side methods. Results Plaque suspensions with L. reuteri DSM 17938 produced significantly less LA compared with L. plantarum 299v or controls (p<0.05). Fructose gave higher LA concentrations than xylitol. In part B, there were no significant differences in LA production between baseline and follow up in any of the groups and no differences between test and placebo were displayed. The salivary MS counts were not significantly altered during the intervention but the lactobacilli counts increased significantly in the test group (p<0.05). Conclusion Lactic acid production in suspensions of plaque and probiotic lactobacilli was strain-dependant and the present study provides no evidence of an increase in plaque acidity by the supply of selected probiotic lactobacilli when challenged by fructose or xylitol. The study protocol was approved by The Danish National Committee on Biomedical Research Ethics (protocol no H-2-2010-112). Trial registration NCT01700712

  4. Light-Stimulated Bacterial Production and Amino Acid Assimilation by Cyanobacteria and Other Microbes in the North Atlantic Ocean▿

    PubMed Central

    Michelou, Vanessa K.; Cottrell, Matthew T.; Kirchman, David L.

    2007-01-01

    We examined the contribution of photoheterotrophic microbes—those capable of light-mediated assimilation of organic compounds—to bacterial production and amino acid assimilation along a transect from Florida to Iceland from 28 May to 9 July 2005. Bacterial production (leucine incorporation at a 20 nM final concentration) was on average 30% higher in light than in dark-incubated samples, but the effect varied greatly (3% to 60%). To further characterize this light effect, we examined the abundance of potential photoheterotrophs and measured their contribution to bacterial production and amino acid assimilation (0.5 nM addition) using flow cytometry. Prochlorococcus and Synechococcus were abundant in surface waters where light-dependent leucine incorporation was observed, whereas aerobic anoxygenic phototrophic bacteria were abundant but did not correlate with the light effect. The per-cell assimilation rates of Prochlorococcus and Synechococcus were comparable to or higher than those of other prokaryotes, especially in the light. Picoeukaryotes also took up leucine (20 nM) and other amino acids (0.5 nM), but rates normalized to biovolume were much lower than those of prokaryotes. Prochlorococcus was responsible for 80% of light-stimulated bacterial production and amino acid assimilation in surface waters south of the Azores, while Synechococcus accounted for on average 12% of total assimilation. However, nearly 40% of the light-stimulated leucine assimilation was not accounted for by these groups, suggesting that assimilation by other microbes is also affected by light. Our results clarify the contribution of cyanobacteria to photoheterotrophy and highlight the potential role of other photoheterotrophs in biomass production and dissolved-organic-matter assimilation. PMID:17630296

  5. Effects of ensiling treatments on lactic acid production and supplementary methane formation of maize and amaranth--an advanced green biorefining approach.

    PubMed

    Haag, Nicola Leonard; Nägele, Hans-Joachim; Fritz, Thomas; Oechsner, Hans

    2015-02-01

    A green biorefinery enables the material and energetic use of biomass via lactic acid and methane production. Different ensiling techniques were applied to maize and amaranth with the aim to increase the amount of lactic acid in the silage. In addition the methane formation potential of the ensiled samples and the remaining solid residues after separating the organic juice were assessed. Treating maize with homofermentative lactic acid bacteria in combination with carbonated lime increased the amount of lactic acid about 91.9%. For amaranth no additional lactic acid production was obtained by treating the raw material. Specific methane yields for the solid residues of amaranth were significantly lower in comparison to the corresponding silages. The most promising treatment resulted in a production of 127.9±4.1 g kg(-1) DM lactic acid and a specific methane yield for the solid residue of 349.5±6.6 lN kg(-1) ODM. Copyright © 2014 Elsevier Ltd. All rights reserved.

  6. Lactic acid production from xylose by Geobacillus stearothermophilus strain 15

    NASA Astrophysics Data System (ADS)

    Kunasundari, B.; Naresh, S.; Chu, J. E.

    2017-09-01

    Lactic acid is an important compound with a wide range of industrial applications. The present study tested the efficiency of xylose, as a sole carbon source to be converted to lactic acid by Geobacillus stearothermophilus strain 15. To the best of our knowledge, limited information is available on the directed fermentation of xylose to lactic acid by this bacterium. The effects of different parameters such as temperature, pH, incubation time, agitation speed, concentrations of nitrogen and carbon sources on the lactic acid production were investigated statistically. It was found that the bacterium exhibited poor assimilation of xylose to lactic acid. Temperature, agitation rate and incubation time were determined to improve the lactic acid production slightly. The highest lactic acid yield obtained was 8.9% at 45°C, 300 RPM, 96 h, pH of 6.0 with carbon and nitrogen source concentrations were fixed at 5% w/v.

  7. Succinic acid production from corn cob hydrolysates by genetically engineered Corynebacterium glutamicum.

    PubMed

    Wang, Chen; Zhang, Hengli; Cai, Heng; Zhou, Zhihui; Chen, Yilu; Chen, Yali; Ouyang, Pingkai

    2014-01-01

    Corynebacterium glutamicum wild type lacks the ability to utilize the xylose fractions of lignocellulosic hydrolysates. In the present work, we constructed a xylose metabolic pathway in C. glutamicum by heterologous expression of the xylA and xylB genes coming from Escherichia coli. Dilute-acid hydrolysates of corn cobs containing xylose and glucose were used as a substrate for succinic acid production by recombinant C. glutamicum NC-2. The results indicated that the available activated charcoal pretreatment in dilute-acid hydrolysates of corn cobs could be able to overcome the inhibitory effect in succinic acid production. Succinic acid was shown to be efficiently produced from corn cob hydrolysates (55 g l(-1) xylose and 4 g l(-1) glucose) under oxygen deprivation with addition of sodium carbonate. Succinic acid concentration reached 40.8 g l(-1) with a yield of 0.69 g g(-1) total sugars within 48 h. It was the first report of succinic acid production from corn cob hydrolysates by metabolically engineered C. glutamicum. This study suggested that dilute-acid hydrolysates of corn cobs may be an alternative substrate for the efficient production of succinic acid by C. glutamicum.

  8. Low-pH production of D-lactic acid using newly isolated acid tolerant yeast Pichia kudriavzevii NG7.

    PubMed

    Park, Hyun Joo; Bae, Jung-Hoon; Ko, Hyeok-Jin; Lee, Sun-Hee; Sung, Bong Hyun; Han, Jong-In; Sohn, Jung-Hoon

    2018-06-13

    Lactic acid is a platform chemical for the sustainable production of various materials. To develop a robust yeast platform for low-pH production of D-lactic acid, an acid-tolerant yeast strain was isolated from grape skins and named Pichia kudriavzevii NG7 by ribosomal RNA sequencing. This strain was able to grow at pH 2.0 and 50°C. For the commercial application of P. kudriavzevii NG7 as a lactic acid producer, the ethanol fermentation pathway was redirected to lactic acid by replacing pyruvate decarboxylase 1 gene (PDC1) with D-lactate dehydrogenase gene (D-LDH) derived from Lactobacillus plantarum. To enhance lactic acid tolerance, this engineered strain was adapted to high lactic acid concentrations, and a new transcriptional regulator, PAR1, responsible for acid tolerance, was identified by whole-genome resequencing. The final engineered strain produced 135 g/L and 154 g/L of D-lactic acid with productivity over 3.66 g/L/h at pH 3.6 and 4.16 g/L/h at pH 4.7, respectively. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  9. Complete genome sequence of probiotic Bacillus coagulans HM-08: A potential lactic acid producer.

    PubMed

    Yao, Guoqiang; Gao, Pengfei; Zhang, Wenyi

    2016-06-20

    Bacillus coagulans HM-08 is a commercialized probiotic strain in China. Its genome contains a 3.62Mb circular chromosome with an average GC content of 46.3%. In silico analysis revealed the presence of one xyl operon as well as several other genes that are correlated to xylose utilization. The genetic information provided here may help to expand its future biotechnology potential in lactic acid production. Copyright © 2016 Elsevier B.V. All rights reserved.

  10. Production of 5'-phosphodiesterase by Catharanthus roseus cells promoted by heat-degraded products generated from uronic acid.

    PubMed

    Akimoto-Tomiyama, Chiharu; Aoyagi, Hideki; Ozawa, Tetsuo; Tanaka, Hideo

    2002-01-01

    Polyalginate was autoclaved at 121 degrees C for 20 min and its molecular weight distribution was analyzed. The autoclaved alginate yielded alginate polymer, oligomer and heat degraded products (HDPs). Each of the separated substances promoted 5'-phosphodiesterase (5'-PDase) production in suspension culture of Catharanthus roseus cells. HDPs could also be generated from other uronic acids (galacturonic acid and glucuronic acid) by autoclave treatment. The most effective substance in the HDPs was isolated and characterized as trans-4,5-dihydroxy-2-cyclopenten-1-one (DHCP). The optimal conditions for DHCP production were also established (autoclaving 1 mg/ml monogalacturonic acid [pH 2] at 121 degrees C for 2 h). A combination of oligo-alginate (below 4 kDa) and HDPs significantly promoted the production of 5'-PDase in C. roseus. Based on the above results, a novel alginate complex that gave a 44-fold increase in 5'-PDase production by C. roseus was developed.

  11. Regulation of lithospermic acid B and shikonin production in Lithospermum erythrorhizon cell suspension cultures.

    PubMed

    Yamamoto, Hirobumi; Zhao, Ping; Yazaki, Kazufumi; Inoue, Kenichiro

    2002-08-01

    Cell suspension cultures of Lithospermum erythrorhizon produced a large amount of lithospermic acid B, a caffeic acid tetramer, as well as shikonin derivatives (each ca. 10% of dry wt.) when cultured in shikonin production medium M-9. Various culture factors for increasing the production of lithospermic acid B were investigated. Lithospermic acid B production was inhibited by 2, 4-D or NH4+, whereas it was stimulated by Cu2+. These regulatory patterns were similar to those for the production of shikonin derivatives in these cell cultures, suggestive of close relations and similar metabolic regulation between the production of these compounds. Cultivation under light illumination, however, showed that these metabolisms were independently regulated. In particular, blue light showed a stimulatory effect on lithospermic acid B production, while shikonin production was strongly inhibited, indicative of an effective condition for lithospermic acid B production.

  12. Production of ω-hydroxy octanoic acid with Escherichia coli.

    PubMed

    Kirtz, Marko; Klebensberger, Janosch; Otte, Konrad B; Richter, Sven M; Hauer, Bernhard

    2016-07-20

    The present proof-of-concept study reports the construction of a whole-cell biocatalyst for the de novo production of ω-hydroxy octanoic acid. This was achieved by hijacking the natural fatty acid cycle and subsequent hydroxylation using a specific monooxygenase without the need for the additional feed of alkene-like precursors. For this, we used the model organism Escherichia coli and increased primarily the release of the octanoic acid precursors by overexpressing the plant thioesterase FatB2 from Cuphea hookeriana in a β-oxidation deficient strain, which lead to the production of 2.32mM (8.38mggcww(-1)) octanoic acid in 24h. In order to produce the corresponding ω-hydroxy derivative, we additionally expressed the engineered self-sufficient monooxygenase fusion protein CYP153AMaq(G307A)-CPRBM3 within the octanoic acid producing strain. With this, we finally produced 234μM (0.95mggcww(-1)) ω-hydroxy octanoic acid in a 20h fed-batch set-up. Copyright © 2016 Elsevier B.V. All rights reserved.

  13. Methyl Jasmonate and Salicylic Acid Enhanced the Production of Ursolic and Oleanolic Acid in Callus Cultures of Lepechinia Caulescens

    PubMed Central

    Vergara Martínez, Víctor M.; Estrada-Soto, Samuel E.; Arellano-García, José de Jesús; Rivera-Leyva, Julio C.; Castillo-España, Patricia; Flores, Angélica Flores; Cardoso-Taketa, Alexandre T.; Perea-Arango, Irene

    2017-01-01

    Background: The production of triterpenes from plants for pharmacological purposes varies in concentration, due to genetic and environmental factors. In vitro culture enables the control and increase of these bioactive molecules. Objective: To evaluate the effect of plant growth regulators and elicitors in the induction of calli and the production of ursolic acid (UA) and oleanolic acid (OA) in Lepechinia caulescens. Materials and Methods: Leaf explants were exposed for the induction of calli at different concentrations and combinations of 2,4-dichlorophenoxyacetic acid (2,4-D) and 6-benzylaminopurine (BAP). Methyl jasmonate (MJ) and salicylic acid were used as elicitors. High-performance liquid chromatography method was used to quantify UA and OA content in each treatment. Results: Treatment with 3.0 mg/L of 2,4-D and 0.1 mg/L of BAP produced the best results for calli induction and production of UA (1.57 mg/g dry weight [DW]) and OA (1.13 mg/g DW). Both elicitors facilitated the accumulation of triterpenes. Conclusion: The combination of auxins and cytokinins showed favorable results for the induction of calli. Variation concerning the accumulation of UA and OA was observed between treatments. MJ increased the production of triterpenes five times after 8 h of exposure, compared to control treatment. There is a greater accumulation of UA (16.58 mg/g DW) and OA (1.94 mg/g DW) in leaves of wild plants. SUMMARY Callus cultures of Lepechinia caulescens were obtained from leaf explants treated with 2,4-dichlorophenoxyacetic acid and 6-bencylaminopurineResulting cultures were elicited with methyl jasmonate (MJ) and salicylic acid to increase the production of the triterpenes, ursolic acid (UA), and oleanolic acid (OA)The cultures elicited with MJ increased the production of UA and OA five times, as compared to the control. Abbreviations used: 2,4-D: 2,4-dichlorophenoxyacetic acid, BAP: 6-benzylaminopurine, DW: Dry weight, MJ: Methyl jasmonate, OA: Oleanolic acid, PGRs

  14. Bio-based production of methacrylic acid

    USDA-ARS?s Scientific Manuscript database

    Methacrylic acid (MAA) is an important industrial chemical commodity, with annual production exceeding 3 million metric tons and a market value surpassing $9 billion. The primary use of MAA is the conversion to ester derivatives, which are further converted into numerous useful polymers. Despite the...

  15. PLASMA PROTEIN PRODUCTION INFLUENCED BY AMINO ACID MIXTURES AND LACK OF ESSENTIAL AMINO ACIDS

    PubMed Central

    Madden, S. C.; Anderson, F. W.; Donovan, J. C.; Whipple, G. H.

    1945-01-01

    When blood plasma proteins are depleted by bleeding with return of red cells suspended in saline (plasmapheresis) it is possible to bring dogs to a steady state of hypoproteinemia and a constant level of plasma protein production if the diet nitrogen intake is controlled and limited. Such dogs are outwardly normal but have a lowered resistance to infection and intoxication and probably to vitamin deficiency. When the diet nitrogen is provided by certain mixtures of the ten growth essential amino acids plus glycine, given intravenously at a rapid rate, plasma protein production is good. The same mixture absorbed subcutaneously at a slower rate may be slightly better utilized. Fed orally the same mixture is better utilized and associated with a lower urinary nitrogen excretion. An ample amino acid mixture for the daily intake of a 10 kilo dog may contain in grams dl-threonine 1.4, dl-valine 3, dl-leucine 3, dl-isoleucine 2, l(+)-lysine·HCl·H2O 2.2, dl-tryptophane 0.3, dl-phenylalanine 2, dl-methionine 1.2, l(+)-histidine·HCl·H2O 1, l(+)-arginine·HCl 1, and glycine 2. Half this quantity is inadequate and not improved by addition of a mixture of alanine, serine, norleucine, proline, hydroxyproline, and tyrosine totalling 1.4 gm. Aspartic acid appears to induce vomiting when added to a mixture of amino acids. The same response has been reported for glutamic acid (8). Omission from the intake of leucine or of leucine and isoleucine results in negative nitrogen balance and rapid weight loss but plasma protein production may be temporarily maintained. It is possible that leucine may be captured from red blood cell destruction. Tryptophane deficiency causes an abrupt decline in plasma protein production. No decline occurred during 2 weeks of histidine deficiency but the urinary nitrogen increased to negative balance. Plasma protein production may be impaired during conditions of dietary deficiency not related to the protein or amino acid intake. Skin lesions and liver

  16. Semicontinuous Production of Lactic Acid From Cheese Whey Using Integrated Membrane Reactor

    NASA Astrophysics Data System (ADS)

    Li, Yebo; Shahbazi, Abolghasem; Coulibaly, Sekou; Mims, Michele M.

    Semicontinuous production of lactic acid from cheese whey using free cells of Bifidobacterium longum with and without nanofiltration was studied. For the semicontinuous fermentation without membrane separation, the lactic acid productivity of the second and third runs is much lower than the first run. The semicontinuous fermentation with nanoseparation was run semicontinuously for 72 h with lactic acid to be harvested every 24 h using a nanofiltration membrane unit. The cells and unutilized lactose were kept in the reactor and mixed with newly added cheese whey in the subsequent runs. Slight increase in the lactic acid productivity was observed in the second and third runs during the semicontinuous fermentation with nanofiltration. It can be concluded that nanoseparation could improve the lactic acid productivity of the semicontinuous fermentation process.

  17. Short-chain carboxylic acids, a new class of teratogens: studies of potential biochemical mechanisms.

    PubMed

    Coakley, M E; Rawlings, S J; Brown, N A

    1986-12-01

    Certain short-chain carboxylic acids (SCCA) appear to share a common teratogenic potential, although the structural requirements for activity remain obscure. By using a whole rat embryo culture model system, several biochemical processes have been examined, either as potential initial sites of teratogenic action or as early steps in the pathway to malformation. Valproate, methoxyacetate, and butyrate were the prototype SCCA examined. Measurement of [14C]glucose utilization and lactate production confirmed that energy production by the early organogenesis embryo is predominantly from glycolysis. While the positive control agent, iodoacetate, caused a significant inhibition of lactate production, none of the SCCA affected this process or glucose utilization at teratogenic concentrations. Valproate did not influence embryonic acetyl CoA levels, in marked contrast to the reported response of adult liver, the other major target of valproate toxicity. Pinocytosis by the visceral yolk sac (VYS) was measured by the uptake of [125I]polyvinylpyrrolidone. This process ultimately supplies the embryo with amino-acids and is essential for normal development. SCCA induce morphological abnormalities of the VYS in embryo culture. Pinocytosis was slightly reduced by valporate, but not the other SCCA. However, comparison with the action of an antiserum, for which inhibition of pinocytosis is the initial teratogenic insult, suggests that this is not the mechanism for valproate. Incorporation of [3H]thymidine into embryo or yolk sac was not affected after 3 hr of SCCA exposure, but there was a marked effect of the positive control, hydroxyurea. This suggests that DNA synthesis is not directly influenced by SCCA.(ABSTRACT TRUNCATED AT 250 WORDS)

  18. Short-chain carboxylic acids, a new class of teratogens: studies of potential biochemical mechanisms.

    PubMed Central

    Coakley, M E; Rawlings, S J; Brown, N A

    1986-01-01

    Certain short-chain carboxylic acids (SCCA) appear to share a common teratogenic potential, although the structural requirements for activity remain obscure. By using a whole rat embryo culture model system, several biochemical processes have been examined, either as potential initial sites of teratogenic action or as early steps in the pathway to malformation. Valproate, methoxyacetate, and butyrate were the prototype SCCA examined. Measurement of [14C]glucose utilization and lactate production confirmed that energy production by the early organogenesis embryo is predominantly from glycolysis. While the positive control agent, iodoacetate, caused a significant inhibition of lactate production, none of the SCCA affected this process or glucose utilization at teratogenic concentrations. Valproate did not influence embryonic acetyl CoA levels, in marked contrast to the reported response of adult liver, the other major target of valproate toxicity. Pinocytosis by the visceral yolk sac (VYS) was measured by the uptake of [125I]polyvinylpyrrolidone. This process ultimately supplies the embryo with amino-acids and is essential for normal development. SCCA induce morphological abnormalities of the VYS in embryo culture. Pinocytosis was slightly reduced by valporate, but not the other SCCA. However, comparison with the action of an antiserum, for which inhibition of pinocytosis is the initial teratogenic insult, suggests that this is not the mechanism for valproate. Incorporation of [3H]thymidine into embryo or yolk sac was not affected after 3 hr of SCCA exposure, but there was a marked effect of the positive control, hydroxyurea. This suggests that DNA synthesis is not directly influenced by SCCA.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:3830097

  19. Potential Application of Biohydrogen Production Liquid Waste as Phosphate Solubilizing Agent-A Study Using Soybean Plants.

    PubMed

    Sarma, Saurabh Jyoti; Brar, Satinder Kaur; LeBihan, Yann; Buelna, Gerardo

    2016-03-01

    With CO2 free emission and a gravimetric energy density higher than gasoline, diesel, biodiesel, and bioethanol, biohydrogen is a promising green renewable energy carrier. During fermentative hydrogen production, 60-70 % of the feedstock is converted to different by-products, dominated by organic acids. In the present investigation, a simple approach for value addition of hydrogen production liquid waste (HPLW) containing these compounds has been demonstrated. In soil, organic acids produced by phosphate solubilizing bacteria chelate the cations of insoluble inorganic phosphates (e.g., Ca3 (PO4)2) and make the phosphorus available to the plants. Organic acid-rich HPLW, therefore, has been evaluated as soil phosphate solubilizer. Application of HPLW as soil phosphate solubilizer was found to improve the phosphorus uptake of soybean plants by 2.18- to 2.74-folds. Additionally, 33-100 % increase in seed germination rate was also observed. Therefore, HPLW has the potential to be an alternative for phosphate solubilizing biofertilizers available in the market. Moreover, the strategy can be useful for phytoremediation of phosphorus-rich soil.

  20. Integrated production of lactic acid and biomass on distillery stillage.

    PubMed

    Djukić-Vuković, Aleksandra P; Mojović, Ljiljana V; Vukašinović-Sekulić, Maja S; Nikolić, Svetlana B; Pejin, Jelena D

    2013-09-01

    The possibilities of parallel lactic acid and biomass production in batch and fed-batch fermentation on distillery stillage from bioethanol production were studied. The highest lactic acid yield and productivity of 92.3 % and 1.49 g L(-1) h(-1) were achieved in batch fermentation with initial sugar concentration of 55 g L(-1). A significant improvement of the process was achieved in fed-batch fermentation where the concentration of lactic acid was increased to 47.6 % and volumetric productivity for 21 % over the batch process. A high number of Lactobacillus rhamnosus ATCC 7469 viable cells of 10(9) CFU ml(-1) was attained at the end of fed-batch fermentation. The survival of 92.9 % of L. rhamnosus cells after 3 h of incubation at pH 2.5 validated that the fermentation media remained after lactic acid removal could be used as a biomass-enriched animal feed thus making an additional value to the process.

  1. Scaled-up production of poacic acid, a plant-derived antifungal agent

    DOE PAGES

    Yue, Fengxia; Gao, Ruili; Piotrowski, Jeff S.; ...

    2017-09-01

    Poacic acid, a decarboxylated product from 8–5-diferulic acid that is commonly found in monocot lignocellulosic hydrolysates, has been identified as a natural antifungal agent against economically significant fungi and oomycete plant pathogens. Starting from commercially available or monocot-derivable ferulic acid, a three-step synthetic procedure has been developed for the production of poacic acid needed for field testing in a controlled agricultural setting. First, ferulic acid was esterified to produce ethyl ferulate in 92% yield. Second, peroxidase-catalyzed free radical dehydrodimerization of ethyl ferulate produced crude diferulates, mainly 8–5-diferulate, in 91% yield. Finally, crystalline poacic acid was obtained in 25% yield viamore » alkaline hydrolysis of the crude diferulates after purification by flash-column chromatography. Thus, this new procedure offers two key improvements relevant to large-scale production: 1) bubbling air through the reaction mixture in the second step to remove acetone greatly improves the recovery efficiency of the crude diferulates; and 2) telescoping minor impurities directly into the alkaline hydrolysis step eliminates the need for additional column purifications, thus reducing the overall cost of production and removing a major impediment to process scale-up.« less

  2. Scaled-up production of poacic acid, a plant-derived antifungal agent

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

    Yue, Fengxia; Gao, Ruili; Piotrowski, Jeff S.

    Poacic acid, a decarboxylated product from 8–5-diferulic acid that is commonly found in monocot lignocellulosic hydrolysates, has been identified as a natural antifungal agent against economically significant fungi and oomycete plant pathogens. Starting from commercially available or monocot-derivable ferulic acid, a three-step synthetic procedure has been developed for the production of poacic acid needed for field testing in a controlled agricultural setting. First, ferulic acid was esterified to produce ethyl ferulate in 92% yield. Second, peroxidase-catalyzed free radical dehydrodimerization of ethyl ferulate produced crude diferulates, mainly 8–5-diferulate, in 91% yield. Finally, crystalline poacic acid was obtained in 25% yield viamore » alkaline hydrolysis of the crude diferulates after purification by flash-column chromatography. Thus, this new procedure offers two key improvements relevant to large-scale production: 1) bubbling air through the reaction mixture in the second step to remove acetone greatly improves the recovery efficiency of the crude diferulates; and 2) telescoping minor impurities directly into the alkaline hydrolysis step eliminates the need for additional column purifications, thus reducing the overall cost of production and removing a major impediment to process scale-up.« less

  3. Amino acid composition reveals functional diversity of zooplankton in tropical lakes related to geography, taxonomy and productivity.

    PubMed

    Aranguren-Riaño, Nelson J; Guisande, Cástor; Shurin, Jonathan B; Jones, Natalie T; Barreiro, Aldo; Duque, Santiago R

    2018-07-01

    Variation in resource use among species determines their potential for competition and co-existence, as well as their impact on ecosystem processes. Planktonic crustaceans consume a range of micro-organisms that vary among habitats and species, but these differences in resource consumption are difficult to characterize due to the small size of the organisms. Consumers acquire amino acids from their diet, and the composition of tissues reflects both the use of different resources and their assimilation in proteins. We examined the amino acid composition of common crustacean zooplankton from 14 tropical lakes in Colombia in three regions (the Amazon floodplain, the eastern range of the Andes, and the Caribbean coast). Amino acid composition varied significantly among taxonomic groups and the three regions. Functional richness in amino acid space was greatest in the Amazon, the most productive region, and tended to be positively related to lake trophic status, suggesting the niche breadth of the community could increase with ecosystem productivity. Functional evenness increased with lake trophic status, indicating that species were more regularly distributed within community-wide niche space in more productive lakes. These results show that zooplankton resource use in tropical lakes varies with both habitat and taxonomy, and that lake productivity may affect community functional diversity and the distribution of species within niche space.

  4. Evaluation of improved γ-aminobutyric acid production in yogurt using Lactobacillus plantarum NDC75017.

    PubMed

    Shan, Y; Man, C X; Han, X; Li, L; Guo, Y; Deng, Y; Li, T; Zhang, L W; Jiang, Y J

    2015-04-01

    Most γ-aminobutyric acid (GABA)-producing microorganisms are lactic acid bacteria (LAB), but the yield of GABA is limited in most of these GABA-producing strains. In this study, the production of GABA was carried out by using Lactobacillus plantarum NDC75017, a strain screened from traditional fermented dairy products in China. Concentrations of substrate (l-monosodium glutamate, L-MSG) and coenzyme (pyridoxal-5-phosphate, PLP) of glutamate decarboxylase (GAD) and culture temperature were investigated to evaluate their effects on GABA yield of Lb. plantarum NDC75017. The results indicated that GABA production was related to GAD activity and biomass of Lb. plantarum NDC75017. Response surface methodology was used to optimize conditions of GABA production. The optimal factors for GABA production were L-MSG at 80 mM, PLP at 18 μM, and a culture temperature of 36 °C. Under these conditions, production of GABA was maximized at 314.56 mg/100 g. Addition of Lb. plantarum NDC75017 to a commercial starter culture led to higher GABA production in fermented yogurt. Flavor and texture of the prepared yogurt and the control yogurt did not differ significantly. Thus, Lb. plantarum NDC75017 has good potential for manufacture of GABA-enriched fermented milk products. Copyright © 2015 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  5. Potential impact of acid precipitation on arsenic and selenium.

    PubMed Central

    Mushak, P

    1985-01-01

    The potential impact of acidic precipitation on the environmental mobility of the metalloids arsenic (As) and selenium (Se) has not been given much attention and is poorly understood. As with other elements, the interest here is the potential effect of environmental acidification on environmental behavior in ways that are relevant to human exposure to these metalloids. Available information on acid precipitation and the environmental behavior of these metalloids do, however, permit some preliminary conclusions to be drawn. Both As and Se appear to be mobilized from household plumbing into tap water by the corrosive action of soft, mildly acidic water, while surface water catchment systems in areas impacted by acidic deposition may contain elevated soluble As levels. Acidification of aquatic ecosystems that are drinking water sources may pose the prospect of enhanced release of As from sediment to water as well as reduction in water levels of Se. Acidification of ground waters, where As appears to be especially mobile, is of particular concern in this regard. The potential impact of acidic deposition on As and Se in soils cannot readily be assessed with respect to human exposure, but it would appear that the behavior of these metalloids in poorly buffered, poorly immobilizing soils, e.g., sandy soils of low metal hydrous oxide content, would be most affected. The effect is opposite for the two elements; lowered pH would appear to enhance As mobility and to reduce Se availability. Altered acidity of both soil and aquatic systems poses a risk for altered biotransformation processes involving both As and Se, thereby affecting the relative amounts of different chemical forms varying in their toxicity to humans as well as influencing biogeochemical cycling. PMID:4076075

  6. Potential impact of acid precipitation on arsenic and selenium.

    PubMed

    Mushak, P

    1985-11-01

    The potential impact of acidic precipitation on the environmental mobility of the metalloids arsenic (As) and selenium (Se) has not been given much attention and is poorly understood. As with other elements, the interest here is the potential effect of environmental acidification on environmental behavior in ways that are relevant to human exposure to these metalloids. Available information on acid precipitation and the environmental behavior of these metalloids do, however, permit some preliminary conclusions to be drawn. Both As and Se appear to be mobilized from household plumbing into tap water by the corrosive action of soft, mildly acidic water, while surface water catchment systems in areas impacted by acidic deposition may contain elevated soluble As levels. Acidification of aquatic ecosystems that are drinking water sources may pose the prospect of enhanced release of As from sediment to water as well as reduction in water levels of Se. Acidification of ground waters, where As appears to be especially mobile, is of particular concern in this regard. The potential impact of acidic deposition on As and Se in soils cannot readily be assessed with respect to human exposure, but it would appear that the behavior of these metalloids in poorly buffered, poorly immobilizing soils, e.g., sandy soils of low metal hydrous oxide content, would be most affected. The effect is opposite for the two elements; lowered pH would appear to enhance As mobility and to reduce Se availability. Altered acidity of both soil and aquatic systems poses a risk for altered biotransformation processes involving both As and Se, thereby affecting the relative amounts of different chemical forms varying in their toxicity to humans as well as influencing biogeochemical cycling.

  7. Bioaugmentation with Clostridium tyrobutyricum to improve butyric acid production through direct rice straw bioconversion.

    PubMed

    Chi, Xue; Li, Jianzheng; Wang, Xin; Zhang, Yafei; Leu, Shao-Yuan; Wang, Ying

    2018-05-02

    One-pot bioconversion is an economically attractive biorefinery strategy to reduce enzyme consumption. Direct conversion of lignocellulosic biomass for butyric acid production is still challenging because of competition among microorganisms. In a consolidated hydrolysis/fermentation bioprocessing (CBP) the microbial structure may eventually prefer the production of caproic acid rather than butyric acid production. This paper presents a new bioaugmentation approach for high butyric acid production from rice straw. By dosing 0.03 g/L of Clostridium tyrobutyricum ATCC 25755 in the CBP, an increase of 226% higher butyric acid was yielded. The selectivity and concentration also increased to 60.7% and 18.05 g/L, respectively. DNA-sequencing confirmed the shift of bacterial community in the augmented CBP. Butyric acid producer was enriched in the bioaugmented bacterial community and the bacteria related to long chain acids production was degenerated. The findings may be useful in future research and process design to enhance productivity of desired bio-products. Copyright © 2018 Elsevier Ltd. All rights reserved.

  8. Enhanced H2O2 Production at Reductive Potentials from Oxidized Boron-Doped Ultrananocrystalline Diamond Electrodes.

    PubMed

    Thostenson, James O; Ngaboyamahina, Edgard; Sellgren, Katelyn L; Hawkins, Brian T; Piascik, Jeffrey R; Klem, Ethan J D; Parker, Charles B; Deshusses, Marc A; Stoner, Brian R; Glass, Jeffrey T

    2017-05-17

    This work investigates the surface chemistry of H 2 O 2 generation on a boron-doped ultrananocrystalline diamond (BD-UNCD) electrode. It is motivated by the need to efficiently disinfect liquid waste in resource constrained environments with limited electrical power. X-ray photoelectron spectroscopy was used to identify functional groups on the BD-UNCD electrode surfaces while the electrochemical potentials of generation for these functional groups were determined via cyclic voltammetry, chronocoulometry, and chronoamperometry. A colorimetric technique was employed to determine the concentration and current efficiency of H 2 O 2 produced at different potentials. Results showed that preanodization of an as-grown BD-UNCD electrode can enhance the production of H 2 O 2 in a strong acidic environment (pH 0.5) at reductive potentials. It is proposed that the electrogeneration of functional groups at oxidative potentials during preanodization allows for an increased current density during the successive electrolysis at reductive potentials that correlates to an enhanced production of H 2 O 2 . Through potential cycling methods, and by optimizing the applied potentials and duty cycle, the functional groups can be stabilized allowing continuous production of H 2 O 2 more efficiently compared to static potential methods.

  9. 40 CFR 415.280 - Applicability; description of the boric acid production subcategory.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... CATEGORY Boric Acid Production Subcategory § 415.280 Applicability; description of the boric acid... production of boric acid from ore-mined borax and from borax produced by the Trona process. ... 40 Protection of Environment 30 2013-07-01 2012-07-01 true Applicability; description of the boric...

  10. 40 CFR 415.280 - Applicability; description of the boric acid production subcategory.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... CATEGORY Boric Acid Production Subcategory § 415.280 Applicability; description of the boric acid... production of boric acid from ore-mined borax and from borax produced by the Trona process. ... 40 Protection of Environment 29 2014-07-01 2012-07-01 true Applicability; description of the boric...

  11. 40 CFR 415.280 - Applicability; description of the boric acid production subcategory.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... CATEGORY Boric Acid Production Subcategory § 415.280 Applicability; description of the boric acid... production of boric acid from ore-mined borax and from borax produced by the Trona process. ... 40 Protection of Environment 29 2011-07-01 2009-07-01 true Applicability; description of the boric...

  12. 40 CFR 415.280 - Applicability; description of the boric acid production subcategory.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... CATEGORY Boric Acid Production Subcategory § 415.280 Applicability; description of the boric acid... production of boric acid from ore-mined borax and from borax produced by the Trona process. ... 40 Protection of Environment 28 2010-07-01 2010-07-01 true Applicability; description of the boric...

  13. Production of Fatty Acid-Derived Valuable Chemicals in Synthetic Microbes

    PubMed Central

    Yu, Ai-Qun; Pratomo Juwono, Nina Kurniasih; Leong, Susanna Su Jan; Chang, Matthew Wook

    2014-01-01

    Fatty acid derivatives, such as hydroxy fatty acids, fatty alcohols, fatty acid methyl/ethyl esters, and fatty alka(e)nes, have a wide range of industrial applications including plastics, lubricants, and fuels. Currently, these chemicals are obtained mainly through chemical synthesis, which is complex and costly, and their availability from natural biological sources is extremely limited. Metabolic engineering of microorganisms has provided a platform for effective production of these valuable biochemicals. Notably, synthetic biology-based metabolic engineering strategies have been extensively applied to refactor microorganisms for improved biochemical production. Here, we reviewed: (i) the current status of metabolic engineering of microbes that produce fatty acid-derived valuable chemicals, and (ii) the recent progress of synthetic biology approaches that assist metabolic engineering, such as mRNA secondary structure engineering, sensor-regulator system, regulatable expression system, ultrasensitive input/output control system, and computer science-based design of complex gene circuits. Furthermore, key challenges and strategies were discussed. Finally, we concluded that synthetic biology provides useful metabolic engineering strategies for economically viable production of fatty acid-derived valuable chemicals in engineered microbes. PMID:25566540

  14. Antimatter Production at a Potential Boundary

    NASA Technical Reports Server (NTRS)

    LaPointe, Michael R.; Reddy, Dhanireddy (Technical Monitor)

    2001-01-01

    Current antiproton production techniques rely on high-energy collisions between beam particles and target nuclei to produce particle and antiparticle pairs, but inherently low production and capture efficiencies render these techniques impractical for the cost-effective production of antimatter for space propulsion and other commercial applications. Based on Dirac's theory of the vacuum field, a new antimatter production concept is proposed in which particle-antiparticle pairs are created at the boundary of a steep potential step formed by the suppression of the local vacuum fields. Current antimatter production techniques are reviewed, followed by a description of Dirac's relativistic quantum theory of the vacuum state and corresponding solutions for particle tunneling and reflection from a potential barrier. The use of the Casimir effect to suppress local vacuum fields is presented as a possible technique for generating the sharp potential gradients required for particle-antiparticle pair creation.

  15. Genetic and metabolic engineering for microbial production of poly-γ-glutamic acid.

    PubMed

    Cao, Mingfeng; Feng, Jun; Sirisansaneeyakul, Sarote; Song, Cunjiang; Chisti, Yusuf

    2018-05-28

    Poly-γ-glutamic acid (γ-PGA) is a natural biopolymer of glutamic acid. The repeating units of γ-PGA may be derived exclusively from d-glutamic acid, or l-glutamic acid, or both. The monomer units are linked by amide bonds between the α-amino group and the γ-carboxylic acid group. γ-PGA is biodegradable, edible and water-soluble. It has numerous existing and emerging applications in processing of foods, medicines and cosmetics. This review focuses on microbial production of γ-PGA via genetically and metabolically engineered recombinant bacteria. Strategies for improving production of γ-PGA include modification of its biosynthesis pathway, enhancing the production of its precursor (glutamic acid), and preventing loss of the precursor to competing byproducts. These and other strategies are discussed. Heterologous synthesis of γ-PGA in industrial bacterial hosts that do not naturally produce γ-PGA is discussed. Emerging trends and the challenges affecting the production of γ-PGA are reviewed. Copyright © 2018. Published by Elsevier Inc.

  16. Interaction effects of lactic acid and acetic acid at different temperatures on ethanol production by Saccharomyces cerevisiae in corn mash.

    PubMed

    Graves, Tara; Narendranath, Neelakantam V; Dawson, Karl; Power, Ronan

    2007-01-01

    The combined effects of lactic acid and acetic acid on ethanol production by S. cerevisiae in corn mash, as influenced by temperature, were examined. Duplicate full factorial experiments (three lactic acid concentrations x three acetic acid concentrations) were performed to evaluate the interaction between lactic and acetic acids on the ethanol production of yeast at each of the three temperatures, 30, 34, and 37 degrees C. Corn mash at 30% dry solids adjusted to pH 4 after lactic and acetic acid addition was used as the substrate. Ethanol production rates and final ethanol concentrations decreased (P<0.001) progressively as the concentration of combined lactic and acetic acids in the corn mash increased and the temperature was raised from 30 to 37 degrees C. At 30 degrees C, essentially no ethanol was produced after 96 h when 0.5% w/v acetic acid was present in the mash (with 0.5, 2, and 4% w/v lactic acid). At 34 and 37 degrees C, the final concentrations of ethanol produced by the yeast were noticeably reduced by the presence of 0.3% w/v acetic acid and >or=2% w/v lactic acid. It can be concluded that, as in previous studies with defined media, lactic acid and acetic acid act synergistically to reduce ethanol production by yeast in corn mash. In addition, the inhibitory effects of combined lactic and acetic acid in corn mash were more apparent at elevated temperatures.

  17. Systems metabolic engineering design: Fatty acid production as an emerging case study

    PubMed Central

    Tee, Ting Wei; Chowdhury, Anupam; Maranas, Costas D; Shanks, Jacqueline V

    2014-01-01

    Increasing demand for petroleum has stimulated industry to develop sustainable production of chemicals and biofuels using microbial cell factories. Fatty acids of chain lengths from C6 to C16 are propitious intermediates for the catalytic synthesis of industrial chemicals and diesel-like biofuels. The abundance of genetic information available for Escherichia coli and specifically, fatty acid metabolism in E. coli, supports this bacterium as a promising host for engineering a biocatalyst for the microbial production of fatty acids. Recent successes rooted in different features of systems metabolic engineering in the strain design of high-yielding medium chain fatty acid producing E. coli strains provide an emerging case study of design methods for effective strain design. Classical metabolic engineering and synthetic biology approaches enabled different and distinct design paths towards a high-yielding strain. Here we highlight a rational strain design process in systems biology, an integrated computational and experimental approach for carboxylic acid production, as an alternative method. Additional challenges inherent in achieving an optimal strain for commercialization of medium chain-length fatty acids will likely require a collection of strategies from systems metabolic engineering. Not only will the continued advancement in systems metabolic engineering result in these highly productive strains more quickly, this knowledge will extend more rapidly the carboxylic acid platform to the microbial production of carboxylic acids with alternate chain-lengths and functionalities. PMID:24481660

  18. Production of l(+)-lactic acid from acid pretreated sugarcane bagasse using Bacillus coagulans DSM2314 in a simultaneous saccharification and fermentation strategy.

    PubMed

    van der Pol, Edwin C; Eggink, Gerrit; Weusthuis, Ruud A

    2016-01-01

    Sugars derived from lignocellulose-rich sugarcane bagasse can be used as feedstock for production of l(+)-lactic acid, a precursor for renewable bioplastics. In our research, acid-pretreated bagasse was hydrolysed with the enzyme cocktail GC220 and fermented by the moderate thermophilic bacterium Bacillus coagulans DSM2314. Saccharification and fermentation were performed simultaneously (SSF), adding acid-pretreated bagasse either in one batch or in two stages. SSF was performed at low enzyme dosages of 10.5-15.8 FPU/g DW bagasse. The first batch SSF resulted in an average productivity of 0.78 g/l/h, which is not sufficient to compete with lactic acid production processes using high-grade sugars. Addition of 1 g/l furfural to precultures can increase B. coagulans resistance towards by-products present in pretreated lignocellulose. Using furfural-containing precultures, productivity increased to 0.92 g/l/h, with a total lactic acid production of 91.7 g in a 1-l reactor containing 20% W/W DW bagasse. To increase sugar concentrations, bagasse was solubilized with a liquid fraction, obtained directly after acid pretreatment. Solubilizing the bagasse fibres with water increased the average productivity to 1.14 g/l/h, with a total lactic acid production of 84.2 g in a 1-l reactor. Addition of bagasse in two stages reduced viscosity during SSF, resulting in an average productivity in the first 23 h of 2.54 g/l/h, similar to productivities obtained in fermentations using high-grade sugars. Due to fast accumulation of lactic acid, enzyme activity was repressed during two-stage SSF, resulting in a decrease in productivity and a slightly lower total lactic acid production of 75.6 g. In this study, it is shown that an adequate production of lactic acid from lignocellulose was successfully accomplished by a two-stage SSF process, which combines acid-pretreated bagasse, B. coagulans precultivated in the presence of furfural as microorganism, and GC220 as enzyme

  19. L-lactic acid production from apple pomace by sequential hydrolysis and fermentation.

    PubMed

    Gullón, Beatriz; Yáñez, Remedios; Alonso, José Luis; Parajó, J C

    2008-01-01

    The potential of apple pomace (a solid waste from cider and apple juice making factories) as a source of sugars and other compounds for fermentation was evaluated. The effect of the cellulase-to-solid ratio (CSR) and the liquor-to-solid ratio (LSR) on the kinetics of glucose and total monosaccharide generation was studied. Mathematical models suitable for reproducing and predicting the hydrolyzate composition were developed. When samples of apple pomace were subjected to enzymatic hydrolysis, the glucose and fructose present in the raw material as free monosaccharides were extracted at the beginning of the process. Using low cellulase and cellobiase charges (8.5 FPU/g-solid and 8.5 IU/g-solid, respectively), 79% of total glucan was saccharified after 12 h, leading to solutions containing up to 43.8 g monosaccharides/L (glucose, 22.8 g/L; fructose, 14.8 g/L; xylose+mannose+galactose, 2.5 g/L; arabinose+rhamnose, 2.8g/L). These results correspond to a monosaccharide/cellulase ratio of 0.06 g/FPU and to a volumetric productivity of 3.65 g of monosaccharides/L h. Liquors obtained under these conditions were used for fermentative lactic acid production with Lactobacillus rhamnosus CECT-288, leading to media containing up to 32.5 g/L of L-lactic acid after 6 h (volumetric productivity=5.41 g/L h, product yield=0.88 g/g).

  20. Production of amino acids - Genetic and metabolic engineering approaches.

    PubMed

    Lee, Jin-Ho; Wendisch, Volker F

    2017-12-01

    The biotechnological production of amino acids occurs at the million-ton scale and annually about 6milliontons of l-glutamate and l-lysine are produced by Escherichia coli and Corynebacterium glutamicum strains. l-glutamate and l-lysine production from starch hydrolysates and molasses is very efficient and access to alternative carbon sources and new products has been enabled by metabolic engineering. This review focusses on genetic and metabolic engineering of amino acid producing strains. In particular, rational approaches involving modulation of transcriptional regulators, regulons, and attenuators will be discussed. To address current limitations of metabolic engineering, this article gives insights on recent systems metabolic engineering approaches based on functional tools and method such as genome reduction, amino acid sensors based on transcriptional regulators and riboswitches, CRISPR interference, small regulatory RNAs, DNA scaffolding, and optogenetic control, and discusses future prospects. Copyright © 2017 Elsevier Ltd. All rights reserved.

  1. Potential of Macroalgae Ulva lactuca as a Source Feedstock for Biodiesel Production.

    PubMed

    Abd El Baky, Hanaa H; El Baroty, Gamal S

    2017-01-01

    The aim of this study was to investigate the possibility of growing of algae Ulva lactuca L.under different salinity levels coupled with varied KNO3 concentrations (source of N) as a potential source of oil for biodiesel production. U. lactuta was cultured in 10.0% NaCl coupled with either 2.5 g/L (S1+ 1N) or 1.0 g/L KNO3 (S1+ 2N) and in 30.0% NaCl coupled with 2.5 g/L (S2+ 1N) or 1.0 g/L KNO3 (S2+ 2N) nutrient medium. Among all algae cultures, biomass (dry weight) and lipid accumulation (total lipid content, TL) were significantly different (P>0.5%), with various degrees. The TL was increased (8.21% to 15.95%, g/100g) by increasing the NaCl % (from 10% to 30%) coupled with the depletion of KNO3 level (from 2.5% to 1%) in culture medium. High lipid content (15.95%) was obtained in S2+ 2N culture, this lipid showed physical (density, viscosity and average molecular weight) and chemical (iodine, acid, saponification and peroxide values) properties suitable for biodiesel production. The fatty acid methyl esters (FAME, biodiesel) prepared by trans-esterifiction reaction under acidic condition were mainly composed of saturated (50.33%), monounsaturated (MUFA, 36.12%) and polyunsaturated (13.55%) esters. C-18:1 was found to be the main MUFA, representing 25.76% of total FAME. On the other hand, the values of some critical of physiochemical parameter (density, kinematic viscosity, iodine value, acid value and oxidation stability) of biodiesel were found to meet the standards for a high quality biodiesel. Hence, U. lactuta could be serving as a valuable renewable biomass of oil for biodiesel production. There are recent patents also suggesting use of oil of U. lactuta marine biomass for biodiesel production. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  2. Ninety six well microtiter plate as microbioreactors for production of itaconic acid by six Aspergillus terreus strains

    USDA-ARS?s Scientific Manuscript database

    Itaconic acid (IA) is a building block platform chemical that is currently produced industrially from glucose by fermentation with Aspergillus terreus. However, lignocellulosic biomass has the potential to serve as low cost source of sugars for production of IA. Previously, 100 A. terreus strains we...

  3. [Folic acid fortified foods available in Spain: types of products, level of fortification and target population groups].

    PubMed

    Samaniego Vaesken, M L; Alonso-Aperte, E; Varela-Moreiras, G

    2009-01-01

    Folic acid is a potentially relevant factor in the prevention of a number of pathologies (congenital abnormalities, cardiovascular disease, colorectal cancer and neurocognitive decline). This has led to the introduction of different strategies in order to increase folate intake: nutritional education, pharmacological supplementation and mandatory or voluntary fortification of staple foods with folic acid. In Spain there is a growing number of folic acid fortified products on a voluntary basis, but there is also a lack of reliable data to assess their impact on the population's dietary folate intakes. To gather a better knowledge of folic acid food fortification practices in Spain. A Food Composition Database was developed using data from a market study. Also, previously published data of unfortified staple foods from Food Composition Tables was reviewed. The Database included 260 folic acid fortified food items and it was periodically updated. Food groups included were primarily "Cereals and derivatives" (52%) followed by "Dairy products". Most of these foodstuffs lacked a target population for their consumption (37%) or were aimed at "Weight control" (28%) and "Children" (23%), but only 2% targeted women at a reproductive age. Number of unfortified foods included was 690. Fortification levels declared by manufacturers ranged between 15 and 430% of the Recommended Dietary Allowances (RDA) for folic acid per 100 g/ml, and simultaneous addition of B6 and B12 vitamins was observed in 75% of the products. Currently, Spain market offers a significant number of folic acid fortified products on a voluntary basis and at a level > or = 15% of the RDA per 100 g/ml or serving declared by manufacturers.

  4. High-titer and productivity of l-(+)-lactic acid using exponential fed-batch fermentation with Bacillus coagulans arr4, a new thermotolerant bacterial strain.

    PubMed

    Coelho, Luciana Fontes; Beitel, Susan Michelz; Sass, Daiane Cristina; Neto, Paulo Marcelo Avila; Contiero, Jonas

    2018-04-01

    Bacillus coagulans arr4 is a thermotolerant microorganism with great biotechnological potential for l-(+)-lactic acid production from granulated sugar and yeast extract. The highest l-(+)-lactic acid production was obtained with Ca(OH) 2 . The maximum production of l-(+)-lactic acid (206.81 g/L) was observed in exponential feeding using granulated sugar solution (900 g/L) and yeast extract (1%) at 50 °C, pH 6.5, and initial granulated sugar concentration of 100 g/L at 39 h. 5.3 g/L h productivity and 97% yield were observed, and no sugar remained. Comparing the simple batch with exponential fed-batch fermentation, the l(+) lactic acid production was improved in 133.22% and dry cell weight was improved in 83.29%, using granulated sugar and yeast extract. This study presents the highest productivity of lactic acid ever observed in the literature, on the fermentation of thermotolerant Bacillus sp. as well as an innovative and high-efficiency purification technology, using low-cost substances as Celite and charcoal. The recovery of lactic acid was 86%, with 100% protein removal, and the fermentation medium (brown color) became a colorless solution.

  5. Engineering acyl carrier protein to enhance production of shortened fatty acids.

    PubMed

    Liu, Xueliang; Hicks, Wade M; Silver, Pamela A; Way, Jeffrey C

    2016-01-01

    The acyl carrier protein (ACP) is an essential and ubiquitous component of microbial synthesis of fatty acids, the natural precursor to biofuels. Natural fatty acids usually contain long chains of 16 or more carbon atoms. Shorter carbon chains, with increased fuel volatility, are desired for internal combustion engines. Engineering the length specificity of key proteins in fatty acid metabolism, such as ACP, may enable microbial synthesis of these shorter chain fatty acids. We constructed a homology model of the Synechococcus elongatus ACP, showing a hydrophobic pocket harboring the growing acyl chain. Amino acids within the pocket were mutated to increase steric hindrance to the acyl chain. Certain mutant ACPs, when over-expressed in Escherichia coli, increased the proportion of shorter chain lipids; I75 W and I75Y showed the strongest effects. Expression of I75 W and I75Y mutant ACPs also increased production of lauric acid in E. coli that expressed the C12-specific acyl-ACP thioesterase from Cuphea palustris. We engineered the specificity of the ACP, an essential protein of fatty acid metabolism, to alter the E. coli lipid pool and enhance production of medium-chain fatty acids as biofuel precursors. These results indicate that modification of ACP itself could be combined with enzymes affecting length specificity in fatty acid synthesis to enhance production of commodity chemicals based on fatty acids.

  6. Prediction of the developmental toxicity hazard potential of halogenated drinking water disinfection by-products tested by the in vitro hydra assay

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

    Fu, L.J.; Johnson, E.M.; Newman, L.M.

    A series of seven randomly selected potential halogenated water disinfection by-products were evaluated in vitro by the hydra assay to determine their developmental toxicity hazard potential. For six of the chemicals tested by this assay (dibromoacetonitrile; trichloroacetonitrile; 2-chlorophenol; 2,4,6-trichlorophenol; trichloroacetic acid; dichloroacetone) it was predicted that they would be generally equally toxic to both adult and embryonic mammals when studied by means of standard developmental toxicity teratology tests. However, the potential water disinfection by-product chloroacetic acid (CA) was determined to be over eight times more toxic to the embryonic developmental portion of the assay than it was to the adults.more » Because of this potential selectivity, CA is a high-priority item for developmental toxicity tests in pregnant mammals to confirm or refute its apparent unique developmental hazard potential and/or to establish a NOAEL by the route of most likely human exposure.« less

  7. Efficient production of free fatty acids from ionic liquid-based acid- or enzyme-catalyzed bamboo hydrolysate.

    PubMed

    Mi, Le; Qin, Dandan; Cheng, Jie; Wang, Dan; Li, Sha; Wei, Xuetuan

    2017-03-01

    Two engineered Escherichia coli strains, DQ101 (MG1655 fadD - )/pDQTES and DQ101 (MG1655 fadD - )/pDQTESZ were constructed to investigate the free fatty acid production using ionic liquid-based acid- or enzyme-catalyzed bamboo hydrolysate as carbon source in this study. The plasmid, pDQTES, carrying an acyl-ACP thioesterase 'TesA of E. coli in pTrc99A was constructed firstly, and then (3R)-hydroxyacyl-ACP dehydratase was ligated after the TesA to give the plasmid pDQTESZ. These two strains exhibited efficient fatty acid production when glucose was used as the sole carbon source, with a final concentration of 2.45 and 3.32 g/L, respectively. The free fatty acid production of the two strains on xylose is not as efficient as that on glucose, which was 2.32 and 2.96 g/L, respectively. For mixed sugars, DQ101 (MG1655 fadD - )-based strains utilized glucose and pentose sequentially under the carbon catabolite repression (CCR) regulation. The highest total FFAs concentration from the mixed sugar culture reached 2.81 g/L by DQ101 (MG1655 fadD - )/pDQTESZ. Furthermore, when ionic liquid-based enzyme-catalyzed bamboo hydrolysate was used as the carbon source, the strain DQ101 (MG1655 fadD - )/pDQTESZ could produce 1.23 g/L FFAs with a yield of 0.13 g/g, and while it just produced 0.65 g/L free fatty acid with the ionic liquid-based acid-catalyzed bamboo hydrolysate as the feedstock. The results suggested that enzymatic catalyzed bamboo hydrolysate with ionic liquid pretreatment could serve as an efficient feedstock for free fatty acid production.

  8. Production and identification of a novel compound, 7,10-dihydroxy-8(E)-hexadecenoic acid from palmitoleic acid by Pseudomonas aeruginosa PR3.

    PubMed

    Bae, Jae-Han; Kim, Deuk-Soo; Suh, Min-Jung; Oh, Sei-Ryang; Lee, In-Jung; Kang, Sun-Chul; Hou, Ching T; Kim, Hak-Ryul

    2007-05-01

    Hydroxy fatty acids are considered as important value-added product for industrial application because of their special properties such as higher viscosity and reactivity. Microbial production of the hydroxy fatty acids from various fatty acid substrates have been actively studied using several microorganisms. The new bacterial isolate Pseudomonas aeruginosa (PR3) had been reported to produce mono-, di-, and tri-hydroxy fatty acids from different unsaturated fatty acids. Of those, 7,10-dihydroxy-8(E)-octadecenoic acid (DOD) and 7,10,12-trihydroxy-8(E)-octadecenoic acid (TOD) were produced from oleic acid and ricinoleic acid, respectively. Based on the postulated common metabolic pathway involved in DOD and TOD formation by PR3, it was assumed that palmitoleic acid containing a singular 9-cis double bond, common structural property sharing with oleic acid and ricinoleic acid, could be utilized by PR3 to produce hydroxy fatty acid. In this study, we tried to use palmitoleic acid as substrate for production of hydroxy fatty acid by PR3 and firstly confirmed that PR3 could produce 7,10-dihydroxy-8(E)-hexadecenoic acid (DHD) with 23% yield from palmitoleic acid. DHD production was peaked at 72 h after the substrate was added to the 24-h-culture.

  9. Production of gluconic acid using Micrococcus sp.: optimisation of carbon and nitrogen sources.

    PubMed

    Joshi, V D; Sreekantiah, K R; Manjrekar, S P

    1996-01-01

    A process for production of gluconic acid from glucose by a Micrococcus sp. is described. More than 400 bacterial cultures isolated from local soil were tested for gluconic acid production. Three isolates, were selected on basis of their ability to produce gluconic acid and high titrable acidity. These were identified as Micrococcus sp. and were named M 27, M 54 and M 81. Nutritional and other parameters for maximum production of gluconic acid by the selected isolates were optimised. It was found that Micrococcus sp. isolate M 27 gave highest yield of 8.19 g gluconic acid from 9 g glucose utilised giving 91% conversion effeciency.

  10. Improvement of n-caproic acid production with Ruminococcaceae bacterium CPB6: selection of electron acceptors and carbon sources and optimization of the culture medium.

    PubMed

    Wang, Han; Li, Xiangzhen; Wang, Yi; Tao, Yong; Lu, Shaowen; Zhu, Xiaoyu; Li, Daping

    2018-06-25

    Global energy and resource shortages make it necessary to quest for renewable resources. n-Caproic acid (CA) production based on carboxylate platform by anaerobic fermentation is booming. Recently, a novel Ruminococcaceae bacterium CPB6 is shown to be a potential biotransformation factory for CA production from lactate-containing wastewater. However, little is known about the effects of different electron acceptors (EAs) on the fermentative products of strain CPB6, as well as the optimum medium for CA production. In this study, batch experiments were performed to investigate the fermentative products of strain CPB6 in a lactate medium supplemented with different EAs and sugars. Supplementation of acetate, butyrate and sucrose dramatically increased cell growth and CA production. The addition of propionate or pentanoate resulted in the production of C5 or C7 carboxylic acid, respectively. Further, a Box-Behnken experiment was conducted to optimize the culture medium for CA production. The result indicated that a medium containing 13.30 g/L sucrose, 22.35 g/L lactate and 16.48 g/L butyrate supported high-titer CA production (16.73 g/L) with a maximum productivity of 6.50 g/L/day. This study demonstrated that strain CPB6 could produce C6-C7 carboxylic acids from lactate (as electron donor) with C2-C5 short-chain carboxylic acids (as EAs), but CA (C6 carboxylic acid) was the most major and potential product. Butyrate and sucrose were the most significant EA and carbon source respectively for CA production from lactate by strain CPB6. High titer of CA can be produced from a synthetic substrate containing sucrose, lactate and butyrate. The work provided significant implications for improving CA production in industry-scale.

  11. Expression of dehydratase domains from a polyunsaturated fatty acid synthase increases the production of fatty acids in Escherichia coli.

    PubMed

    Oyola-Robles, Delise; Rullán-Lind, Carlos; Carballeira, Néstor M; Baerga-Ortiz, Abel

    2014-02-05

    Increasing the production of fatty acids by microbial fermentation remains an important step toward the generation of biodiesel and other portable liquid fuels. In this work, we report an Escherichia coli strain engineered to overexpress a fragment consisting of four dehydratase domains from the polyunsaturated fatty acid (PUFA) synthase enzyme complex from the deep-sea bacterium, Photobacterium profundum. The DH1-DH2-UMA enzyme fragment was excised from its natural context within a multi-enzyme PKS and expressed as a stand-alone protein. Fatty acids were extracted from the cell pellet, esterified with methanol and quantified by GC-MS analysis. Results show that the E. coli strain expressing the DH tetradomain fragment was capable of producing up to a 5-fold increase (80.31 mg total FA/L culture) in total fatty acids over the negative control strain lacking the recombinant enzyme. The enhancement in production was observed across the board for all the fatty acids that are typically made by E. coli. The overexpression of the DH tetradomain did not affect E. coli cell growth, thus showing that the observed enhancement in fatty acid production was not a result of effects associated with cell density. The observed enhancement was more pronounced at lower temperatures (3.8-fold at 16 °C, 3.5-fold at 22 °C and 1.5-fold at 30 °C) and supplementation of the media with 0.4% glycerol did not result in an increase in fatty acid production. All these results taken together suggest that either the dehydration of fatty acid intermediates are a limiting step in the E. coli fatty acid biosynthesis machinery, or that the recombinant dehydratase domains used in this study are also capable of catalyzing thioester hydrolysis of the final products. The enzyme in this report is a new tool which could be incorporated into other existing strategies aimed at improving fatty acid production in bacterial fermentations toward accessible biodiesel precursors. Copyright © 2013 Elsevier Inc

  12. Potential Approach of Microbial Conversion to Develop New Antifungal Products of Omega-3 Fatty Acids

    USDA-ARS?s Scientific Manuscript database

    Omega-3/('-3) or n-3 fatty acids are a family of unsaturated fatty acids that have in common a final carbon-carbon double bond in the n-3 position. n-3 Fatty acids which are important in human nutrition are: a-linolenic acid (18:3, n-3; ALA), eicosapentaenoic acid (20:5, n-3; EPA), and docosahexaen...

  13. A study of organic acid production in contrasts between two phosphate solubilizing fungi: Penicillium oxalicum and Aspergillus niger

    NASA Astrophysics Data System (ADS)

    Li, Zhen; Bai, Tongshuo; Dai, Letian; Wang, Fuwei; Tao, Jinjin; Meng, Shiting; Hu, Yunxiao; Wang, Shimei; Hu, Shuijin

    2016-04-01

    Phosphate solubilizing fungi (PSF) have huge potentials in enhancing release of phosphorus from fertilizer. Two PSF (NJDL-03 and NJDL-12) were isolated and identified as Penicillium oxalicum and Aspergillus niger respectively in this study. The quantification and identification of organic acids were performed by HPLC. Total concentrations of organic acids secreted by NJDL-03 and NJDL-12 are ~4000 and ~10,000 mg/L with pH values of 3.6 and 2.4 respectively after five-days culture. Oxalic acid dominates acidity in the medium due to its high concentration and high acidity constant. The two fungi were also cultured for five days with the initial pH values of the medium varied from 6.5 to 1.5. The biomass reached the maximum when the initial pH values are 4.5 for NJDL-03 and 2.5 for NJDL-12. The organic acids for NJDL-12 reach the maximum at the initial pH = 5.5. However, the acids by NJDL-03 continue to decrease and proliferation of the fungus terminates at pH = 2.5. The citric acid production increases significantly for NJDL-12 at acidic environment, whereas formic and oxalic acids decrease sharply for both two fungi. This study shows that NJDL-12 has higher ability in acid production and has stronger adaptability to acidic environment than NJDL-03.

  14. A study of organic acid production in contrasts between two phosphate solubilizing fungi: Penicillium oxalicum and Aspergillus niger

    PubMed Central

    Li, Zhen; Bai, Tongshuo; Dai, Letian; Wang, Fuwei; Tao, Jinjin; Meng, Shiting; Hu, Yunxiao; Wang, Shimei; Hu, Shuijin

    2016-01-01

    Phosphate solubilizing fungi (PSF) have huge potentials in enhancing release of phosphorus from fertilizer. Two PSF (NJDL-03 and NJDL-12) were isolated and identified as Penicillium oxalicum and Aspergillus niger respectively in this study. The quantification and identification of organic acids were performed by HPLC. Total concentrations of organic acids secreted by NJDL-03 and NJDL-12 are ~4000 and ~10,000 mg/L with pH values of 3.6 and 2.4 respectively after five-days culture. Oxalic acid dominates acidity in the medium due to its high concentration and high acidity constant. The two fungi were also cultured for five days with the initial pH values of the medium varied from 6.5 to 1.5. The biomass reached the maximum when the initial pH values are 4.5 for NJDL-03 and 2.5 for NJDL-12. The organic acids for NJDL-12 reach the maximum at the initial pH = 5.5. However, the acids by NJDL-03 continue to decrease and proliferation of the fungus terminates at pH = 2.5. The citric acid production increases significantly for NJDL-12 at acidic environment, whereas formic and oxalic acids decrease sharply for both two fungi. This study shows that NJDL-12 has higher ability in acid production and has stronger adaptability to acidic environment than NJDL-03. PMID:27126606

  15. Discovery of phosphonic acid natural products by mining the genomes of 10,000 actinomycetes.

    PubMed

    Ju, Kou-San; Gao, Jiangtao; Doroghazi, James R; Wang, Kwo-Kwang A; Thibodeaux, Christopher J; Li, Steven; Metzger, Emily; Fudala, John; Su, Joleen; Zhang, Jun Kai; Lee, Jaeheon; Cioni, Joel P; Evans, Bradley S; Hirota, Ryuichi; Labeda, David P; van der Donk, Wilfred A; Metcalf, William W

    2015-09-29

    Although natural products have been a particularly rich source of human medicines, activity-based screening results in a very high rate of rediscovery of known molecules. Based on the large number of natural product biosynthetic genes in microbial genomes, many have proposed "genome mining" as an alternative approach for discovery efforts; however, this idea has yet to be performed experimentally on a large scale. Here, we demonstrate the feasibility of large-scale, high-throughput genome mining by screening a collection of over 10,000 actinomycetes for the genetic potential to make phosphonic acids, a class of natural products with diverse and useful bioactivities. Genome sequencing identified a diverse collection of phosphonate biosynthetic gene clusters within 278 strains. These clusters were classified into 64 distinct groups, of which 55 are likely to direct the synthesis of unknown compounds. Characterization of strains within five of these groups resulted in the discovery of a new archetypical pathway for phosphonate biosynthesis, the first (to our knowledge) dedicated pathway for H-phosphinates, and 11 previously undescribed phosphonic acid natural products. Among these compounds are argolaphos, a broad-spectrum antibacterial phosphonopeptide composed of aminomethylphosphonate in peptide linkage to a rare amino acid N(5)-hydroxyarginine; valinophos, an N-acetyl l-Val ester of 2,3-dihydroxypropylphosphonate; and phosphonocystoximate, an unusual thiohydroximate-containing molecule representing a new chemotype of sulfur-containing phosphonate natural products. Analysis of the genome sequences from the remaining strains suggests that the majority of the phosphonate biosynthetic repertoire of Actinobacteria has been captured at the gene level. This dereplicated strain collection now provides a reservoir of numerous, as yet undiscovered, phosphonate natural products.

  16. Discovery of phosphonic acid natural products by mining the genomes of 10,000 actinomycetes

    PubMed Central

    Ju, Kou-San; Gao, Jiangtao; Doroghazi, James R.; Wang, Kwo-Kwang A.; Thibodeaux, Christopher J.; Li, Steven; Metzger, Emily; Fudala, John; Su, Joleen; Zhang, Jun Kai; Lee, Jaeheon; Cioni, Joel P.; Evans, Bradley S.; Hirota, Ryuichi; Labeda, David P.; van der Donk, Wilfred A.; Metcalf, William W.

    2015-01-01

    Although natural products have been a particularly rich source of human medicines, activity-based screening results in a very high rate of rediscovery of known molecules. Based on the large number of natural product biosynthetic genes in microbial genomes, many have proposed “genome mining” as an alternative approach for discovery efforts; however, this idea has yet to be performed experimentally on a large scale. Here, we demonstrate the feasibility of large-scale, high-throughput genome mining by screening a collection of over 10,000 actinomycetes for the genetic potential to make phosphonic acids, a class of natural products with diverse and useful bioactivities. Genome sequencing identified a diverse collection of phosphonate biosynthetic gene clusters within 278 strains. These clusters were classified into 64 distinct groups, of which 55 are likely to direct the synthesis of unknown compounds. Characterization of strains within five of these groups resulted in the discovery of a new archetypical pathway for phosphonate biosynthesis, the first (to our knowledge) dedicated pathway for H-phosphinates, and 11 previously undescribed phosphonic acid natural products. Among these compounds are argolaphos, a broad-spectrum antibacterial phosphonopeptide composed of aminomethylphosphonate in peptide linkage to a rare amino acid N5-hydroxyarginine; valinophos, an N-acetyl l-Val ester of 2,3-dihydroxypropylphosphonate; and phosphonocystoximate, an unusual thiohydroximate-containing molecule representing a new chemotype of sulfur-containing phosphonate natural products. Analysis of the genome sequences from the remaining strains suggests that the majority of the phosphonate biosynthetic repertoire of Actinobacteria has been captured at the gene level. This dereplicated strain collection now provides a reservoir of numerous, as yet undiscovered, phosphonate natural products. PMID:26324907

  17. Increased Production of Fatty Acids and Triglycerides in Aspergillus oryzae by Enhancing Expressions of Fatty Acid Synthesis-Related Genes

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

    Tamano, Koichi; Bruno, Kenneth S.; Karagiosis, Sue A.

    2013-01-01

    Microbial production of fats and oils is being developedas a means of converting biomass to biofuels. Here we investigate enhancing expression of enzymes involved in the production of fatty acids and triglycerides as a means to increase production of these compounds in Aspergillusoryzae. Examination of the A.oryzaegenome demonstrates that it contains twofatty acid synthases and several other genes that are predicted to be part of this biosynthetic pathway. We enhancedthe expressionof fatty acid synthesis-related genes by replacing their promoters with thepromoter fromthe constitutively highly expressedgene tef1. We demonstrate that by simply increasing the expression of the fatty acid synthasegenes wemore » successfullyincreasedtheproduction of fatty acids and triglyceridesby more than two fold. Enhancement of expression of the fatty acid pathway genes ATP-citrate lyase and palmitoyl-ACP thioesteraseincreasedproductivity to a lesser extent.Increasing expression ofacetyl-CoA carboxylase caused no detectable change in fatty acid levels. Increases in message level for each gene were monitored usingquantitative real-time RT-PCR. Our data demonstrates that a simple increase in the abundance of fatty acid synthase genes can increase the detectable amount of fatty acids.« less

  18. Evidence for the complex relationship between free amino acid and sugar concentrations and acrylamide-forming potential in potato

    PubMed Central

    Muttucumaru, N; Powers, SJ; Elmore, JS; Briddon, A; Mottram, DS; Halford, NG

    2014-01-01

    Free amino acids and reducing sugars participate in the Maillard reaction during high-temperature cooking and processing. This results not only in the formation of colour, aroma and flavour compounds, but also undesirable contaminants, including acrylamide, which forms when the amino acid that participates in the reaction is asparagine. In this study, tubers of 13 varieties of potato (Solanum tuberosum), which had been produced in a field trial in 2010 and sampled immediately after harvest or after storage for 6 months, were analysed to show the relationship between the concentrations of free asparagine, other free amino acids, sugars and acrylamide-forming potential. The varieties comprised five that are normally used for crisping, seven that are used for French fry production and one that is used for boiling. Acrylamide formation was measured in heated flour, and correlated with glucose and fructose concentration. In French fry varieties, which contain higher concentrations of sugars, acrylamide formation also correlated with free asparagine concentration, demonstrating the complex relationship between precursor concentration and acrylamide-forming potential in potato. Storage of the potatoes for 6 months at 9°C had a significant, variety-dependent impact on sugar and amino acid concentrations and acrylamide-forming potential. PMID:25540460

  19. Evaluation of bread crumbs as a potential carbon source for the growth of thraustochytrid species for oil and omega-3 production.

    PubMed

    Thyagarajan, Tamilselvi; Puri, Munish; Vongsvivut, Jitraporn; Barrow, Colin J

    2014-05-23

    The utilization of food waste by microorganisms to produce omega-3 fatty acids or biofuel is a potentially low cost method with positive environmental benefits. In the present study, the marine microorganisms Thraustochytrium sp. AH-2 and Schizochytrium sp. SR21 were used to evaluate the potential of breadcrumbs as an alternate carbon source for the production of lipids under static fermentation conditions. For the Thraustochytrium sp. AH-2, submerged liquid fermentation with 3% glucose produced 4.3 g/L of biomass and 44.16 mg/g of saturated fatty acids after seven days. Static fermentation with 0.5% and 1% breadcrumbs resulted in 2.5 and 4.7 g/L of biomass, and 42.4 and 33.6 mg/g of saturated fatty acids, respectively. Scanning electron microscopic (SEM) studies confirmed the growth of both strains on breadcrumbs. Attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy for both strains were consistent with the utilization of breadcrumbs for the production of unsaturated lipids, albeit at relatively low levels. The total lipid yield for static fermentation with bread crumbs was marginally lower than that of fermentation with glucose media, while the yield of unsaturated fatty acids was considerably lower, indicating that static fermentation may be more appropriate for the production of biodiesel than for the production of omega-3 rich oils in these strains.

  20. Evaluation of Bread Crumbs as a Potential Carbon Source for the Growth of Thraustochytrid Species for Oil and Omega-3 Production

    PubMed Central

    Thyagarajan, Tamilselvi; Puri, Munish; Vongsvivut, Jitraporn; Barrow, Colin J.

    2014-01-01

    The utilization of food waste by microorganisms to produce omega-3 fatty acids or biofuel is a potentially low cost method with positive environmental benefits. In the present study, the marine microorganisms Thraustochytrium sp. AH-2 and Schizochytrium sp. SR21 were used to evaluate the potential of breadcrumbs as an alternate carbon source for the production of lipids under static fermentation conditions. For the Thraustochytrium sp. AH-2, submerged liquid fermentation with 3% glucose produced 4.3 g/L of biomass and 44.16 mg/g of saturated fatty acids after seven days. Static fermentation with 0.5% and 1% breadcrumbs resulted in 2.5 and 4.7 g/L of biomass, and 42.4 and 33.6 mg/g of saturated fatty acids, respectively. Scanning electron microscopic (SEM) studies confirmed the growth of both strains on breadcrumbs. Attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy for both strains were consistent with the utilization of breadcrumbs for the production of unsaturated lipids, albeit at relatively low levels. The total lipid yield for static fermentation with bread crumbs was marginally lower than that of fermentation with glucose media, while the yield of unsaturated fatty acids was considerably lower, indicating that static fermentation may be more appropriate for the production of biodiesel than for the production of omega-3 rich oils in these strains. PMID:24858496

  1. Heterogeneous kinetics, products, and mechanisms of ferulic acid particles in the reaction with NO3 radicals

    NASA Astrophysics Data System (ADS)

    Liu, Changgeng; Zhang, Peng; Wen, Xiaoying; Wu, Bin

    2017-03-01

    Methoxyphenols, as an important component of wood burning, are produced by lignin pyrolysis and considered to be the potential tracers for wood smoke emissions. In this work, the heterogeneous reaction between ferulic acid particles and NO3 radicals was investigated. Six products including oxalic acid, 4-vinylguaiacol, vanillin, 5-nitrovanillin, 5-nitroferulic acid, and caffeic acid were confirmed by gas chromatography-mass spectrometry (GC-MS). In addition, the reaction mechanisms were proposed and the main pathways were NO3 electrophilic addition to olefin and the meta-position to the hydroxyl group. The uptake coefficient of NO3 radicals on ferulic acid particles was 0.17 ± 0.02 and the effective rate constant under experimental conditions was (1.71 ± 0.08) × 10-12 cm3 molecule-1 s-1. The results indicate that ferulic acid degradation by NO3 can be an important sink at night.

  2. High-Yield Production of Levulinic Acid from Pretreated Cow Dung in Dilute Acid Aqueous Solution.

    PubMed

    Su, Jialei; Shen, Feng; Qiu, Mo; Qi, Xinhua

    2017-02-14

    Agricultural waste cow dung was used as feedstock for the production of a high value-added chemical levulinic acid (LA) in dilute acid aqueous solutions. A high LA yield of 338.9 g/kg was obtained from the pretreated cow dung, which was much higher than that obtained from the crude cow dung (135 g/kg), mainly attributed to the breakage of the lignin fraction in the lignocellulose structure of the cow dung by potassium hydroxide (KOH) pretreatment, and thus enhanced the accessibility of cow dung to the acid sites in the catalytic reaction. Meanwhile, another value-added chemical formic acid could be obtained with a yield of ca. 160 g/kg in the process, implying a total production of ca. 500 g/kg yield for LA and formic acid from the pretreated cow dung with the proposed process. The developed process was shown to be tolerant to high initial substrate loading with a satisfied LA yield. This work provides a promising strategy for the value-increment utilization of liglocellulosic agricultural residues.

  3. Systems metabolic engineering design: fatty acid production as an emerging case study.

    PubMed

    Tee, Ting Wei; Chowdhury, Anupam; Maranas, Costas D; Shanks, Jacqueline V

    2014-05-01

    Increasing demand for petroleum has stimulated industry to develop sustainable production of chemicals and biofuels using microbial cell factories. Fatty acids of chain lengths from C6 to C16 are propitious intermediates for the catalytic synthesis of industrial chemicals and diesel-like biofuels. The abundance of genetic information available for Escherichia coli and specifically, fatty acid metabolism in E. coli, supports this bacterium as a promising host for engineering a biocatalyst for the microbial production of fatty acids. Recent successes rooted in different features of systems metabolic engineering in the strain design of high-yielding medium chain fatty acid producing E. coli strains provide an emerging case study of design methods for effective strain design. Classical metabolic engineering and synthetic biology approaches enabled different and distinct design paths towards a high-yielding strain. Here we highlight a rational strain design process in systems biology, an integrated computational and experimental approach for carboxylic acid production, as an alternative method. Additional challenges inherent in achieving an optimal strain for commercialization of medium chain-length fatty acids will likely require a collection of strategies from systems metabolic engineering. Not only will the continued advancement in systems metabolic engineering result in these highly productive strains more quickly, this knowledge will extend more rapidly the carboxylic acid platform to the microbial production of carboxylic acids with alternate chain-lengths and functionalities. © 2014 Wiley Periodicals, Inc.

  4. Central Appalachia: Production potential of low-sulfur coal

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

    Watkins, J.

    The vast preponderance of eastern US low sulfur and 1.2-lbs SO{sub 2}/MMBtu compliance coal comes from a relatively small area composed of 14 counties located in eastern Kentucky, southern West Virginia and western Virginia. These 14 counties accounted for 68% of all Central Appalachian coal production in 1989 as well as 85% of all compliance coal shipped to electric utilities from this region. A property-by-property analysis of total production potential in 10 of the 14 counties (Floyd, Knott, Letcher, Harlan, Martin and Pike in Kentucky and Boone, Kanawha, Logan and Mingo in West Virginia) resulted in the following estimates ofmore » active and yet to be developed properties: (1) total salable reserves for all sulfur levels were 5.9 billion tons and (2) 1.2-lbs. SO{sub 2}/MMBtu compliance'' reserves totaled 2.38 billion tons. This potential supply of compliance coal is adequate to meet the expanded utility demand expected under acid rain for the next 20 years. Beyond 2010, compliance supplies will begin to reach depletion levels in some areas of the study region. A review of the cost structure for all active mines was used to categorize the cost structure for developing potential supplies. FOB cash costs for all active mines in the ten counties ranged from $15 per ton to $35 per ton and the median mine cost was about $22 per ton. A total of 47 companies with the ability to produce and ship coal from owned or leased reserves are active in the ten-county region. Identified development and expansion projects controlled by active companies are capable of expanding the region's current production level by over 30 million tons per year over the next twenty years. Beyond this period the issue of reserve depletion for coal of all sulfur levels in the ten county region will become a pressing issue. 11 figs., 12 tabs.« less

  5. Activation of Short and Long Chain Fatty Acid Sensing Machinery in the Ileum Lowers Glucose Production in Vivo.

    PubMed

    Zadeh-Tahmasebi, Melika; Duca, Frank A; Rasmussen, Brittany A; Bauer, Paige V; Côté, Clémence D; Filippi, Beatrice M; Lam, Tony K T

    2016-04-15

    Evidence continues to emerge detailing the myriad of ways the gut microbiota influences host energy homeostasis. Among the potential mechanisms, short chain fatty acids (SCFAs), the byproducts of microbial fermentation of dietary fibers, exhibit correlative beneficial metabolic effects in humans and rodents, including improvements in glucose homeostasis. The underlying mechanisms, however, remain elusive. We here report that one of the main bacterially produced SCFAs, propionate, activates ileal mucosal free fatty acid receptor 2 to trigger a negative feedback pathway to lower hepatic glucose production in healthy rats in vivo We further demonstrate that an ileal glucagon-like peptide-1 receptor-dependent neuronal network is necessary for ileal propionate and long chain fatty acid sensing to regulate glucose homeostasis. These findings highlight the potential to manipulate fatty acid sensing machinery in the ileum to regulate glucose homeostasis. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

  6. Methods for producing 3-hydroxypropionic acid and other products

    DOEpatents

    Lynch, Michael D.; Gill, Ryan T.; Lipscomb, Tanya E. W.

    2016-07-12

    This invention relates to metabolically engineered microorganism strains, such as bacterial strains, in which there is an increased utilization of malonyl-CoA for production of a chemical product, which includes 3-hydroxypropionic acid.

  7. Method for producing 3-hydroxypropionic acid and other products

    DOEpatents

    Lynch, Michael D.; Gill, Ryan T.; Lipscomb, Tanya E.W.

    2016-08-30

    This invention relates to metabolically engineered microorganism strains, such as bacterial strains, in which there is an increased utilization of malonyl-CoA for production of a chemical product, which includes 3-hydroxypropionic acid.

  8. Production of Biodiesel from Acid Oil via a Two-Step Enzymatic Transesterification.

    PubMed

    Choi, Nakyung; Lee, Jeom-Sig; Kwak, Jieun; Lee, Junsoo; Kim, In-Hwan

    2016-11-01

    A two-step enzymatic transesterification process in a solvent-free system has been developed as a novel approach to the production of biodiesel using acid oil from rice bran oil soapstock. The acid oil consisted of 53.7 wt% fatty acids, 2.4 wt% monoacylglycerols, 9.1 wt% diacylglycerols, 28.8 wt% triacylglycerols, and 6.0 wt% others. Three immobilized lipases were evaluated as potential biocatalysts, including Novozym 435 from Candida antarctica, Lipozyme RM IM from Rhizomucor miehei, and Lipozyme TL IM from Thermomyces lanuginosus. The effects of molar ratio of acid oil to ethanol, temperature, and enzyme loading were investigated to determine the optimum conditions for the transesterification with the three immobilized lipases. The optimum conditions of the three immobilized lipases were a molar ratio of 1:5 (acid oil to ethanol), the temperature range of 30-40°C, and the enzyme loading range of 5-10%. The two-step transesterification was then conducted under the optimum conditions of each lipase. The stepwise use of Novozym 435 and Lipozyme TL IM or Lipozyme RM IM and Lipozyme TL IM resulted in similar or higher levels of yield to the individual lipases. The maximum yields obtained in both stepwise uses were ca. 92%.

  9. Theobromine Inhibits Uric Acid Crystallization. A Potential Application in the Treatment of Uric Acid Nephrolithiasis

    PubMed Central

    Grases, Felix; Rodriguez, Adrian; Costa-Bauza, Antonia

    2014-01-01

    Purpose To assess the capacity of methylxanthines (caffeine, theophylline, theobromine and paraxanthine) to inhibit uric acid crystallization, and to evaluate their potential application in the treatment of uric acid nephrolithiasis. Materials and Methods The ability of methylxathines to inhibit uric acid nucleation was assayed turbidimetrically. Crystal morphology and its modification due to the effect of theobromine were evaluated by scanning electron microscopy (SEM). The ability of theobromine to inhibit uric acid crystal growth on calculi fragments resulting from extracorporeal shock wave lithotripsy (ESWL) was evaluated using a flow system. Results The turbidimetric assay showed that among the studied methylxanthines, theobromine could markedly inhibit uric acid nucleation. SEM images showed that the presence of theobromine resulted in thinner uric acid crystals. Furthermore, in a flow system theobromine blocked the regrowth of post-ESWL uric acid calculi fragments. Conclusions Theobromine, a natural dimethylxanthine present in high amounts in cocoa, acts as an inhibitor of nucleation and crystal growth of uric acid. Therefore, theobromine may be clinically useful in the treatment of uric acid nephrolithiasis. PMID:25333633

  10. Improving itaconic acid production through genetic engineering of an industrial Aspergillus terreus strain.

    PubMed

    Huang, Xuenian; Lu, Xuefeng; Li, Yueming; Li, Xia; Li, Jian-Jun

    2014-08-11

    Itaconic acid, which has been declared to be one of the most promising and flexible building blocks, is currently used as monomer or co-monomer in the polymer industry, and produced commercially by Aspergillus terreus. However, the production level of itaconic acid hasn't been improved in the past 40 years, and mutagenesis is still the main strategy to improve itaconate productivity. The genetic engineering approach hasn't been applied in industrial A. terreus strains to increase itaconic acid production. In this study, the genes closely related to itaconic acid production, including cadA, mfsA, mttA, ATEG_09969, gpdA, ATEG_01954, acoA, mt-pfkA and citA, were identified and overexpressed in an industrial A. terreus strain respectively. Overexpression of the genes cadA (cis-aconitate decarboxylase) and mfsA (Major Facilitator Superfamily Transporter) enhanced the itaconate production level by 9.4% and 5.1% in shake flasks respectively. Overexpression of other genes showed varied effects on itaconate production. The titers of other organic acids were affected by the introduced genes to different extent. Itaconic acid production could be improved through genetic engineering of the industrially used A. terreus strain. We have identified some important genes such as cadA and mfsA, whose overexpression led to the increased itaconate productivity, and successfully developed a strategy to establish a highly efficient microbial cell factory for itaconate protuction. Our results will provide a guide for further enhancement of the itaconic acid production level through genetic engineering in future.

  11. Dye-Sensitized Hydrobromic Acid Splitting for Hydrogen Solar Fuel Production.

    PubMed

    Brady, Matthew D; Sampaio, Renato N; Wang, Degao; Meyer, Thomas J; Meyer, Gerald J

    2017-11-08

    Hydrobromic acid (HBr) has significant potential as an inexpensive feedstock for hydrogen gas (H 2 ) solar fuel production through HBr splitting. Mesoporous thin films of anatase TiO 2 or SnO 2 /TiO 2 core-shell nanoparticles were sensitized to visible light with a new Ru II polypyridyl complex that served as a photocatalyst for bromide oxidation. These thin films were tested as photoelectrodes in dye-sensitized photoelectrosynthesis cells. In 1 N HBr (aq), the photocatalyst undergoes excited-state electron injection and light-driven Br - oxidation. The injected electrons induce proton reduction at a Pt electrode. Under 100 mW cm -2 white-light illumination, sustained photocurrents of 1.5 mA cm -2 were measured under an applied bias. Faradaic efficiencies of 71 ± 5% for Br - oxidation and 94 ± 2% for H 2 production were measured. A 12 μmol h -1 sustained rate of H 2 production was maintained during illumination. The results demonstrate a molecular approach to HBr splitting with a visible light absorbing complex capable of aqueous Br - oxidation and excited-state electron injection.

  12. Potential heat exchange fluids for use in sulfuric acid vaporizers

    NASA Technical Reports Server (NTRS)

    Lawson, D. D.; Petersen, G. R.

    1979-01-01

    A series of perhalocarbons are proposed as candidate heat exchange fluids for service in thermochemical cycles for hydrogen production that involve direct contact of the fluid with sulfuric acid and vaporization of the acid. The required chemical and physical criteria of the liquids are described and the results of some preliminary high temperature test data are presented.

  13. Potential silver nanoparticles migration from commercially available polymeric baby products into food simulants.

    PubMed

    Choi, Jeong In; Chae, Song Ji; Kim, Jung Min; Choi, Jae Chun; Park, Se Jong; Choi, Hee Ju; Bae, Hojae; Park, Hyun Jin

    2018-05-01

    In recent years, silver nanoparticles (AgNPs) have been extensively employed in food packaging systems as a potential antibacterial agent. Although proven to be highly effective, the increased number of AgNP-containing products raises concerns among consumers regarding the migration of AgNPs from the packaging material into foods, which may exert toxic effects. To address this, five baby products were chosen (baby bottle A, baby bottle B, pacifier A, pacifier B and breastmilk storage bag) to investigate AgNPs migration into three food simulants (deionised water, 4% acetic acid (w/v) and 50% ethanol (v/v)) using inductively coupled plasma mass spectrometry (ICP-MS). As a result, the highest level of migrated Ag was observed for 4% acetic acid in the case of baby bottle B, pacifier A, pacifier B and the breastmilk storage bag, with the detection amount ranging from 1.05-2.25 ng/mL. On the other hand, baby bottle A showed the maximum migration for 50% ethanol due to the polymer nature. Finally, a centrifugal ultrafiltration experiment was conducted to determine the fraction of dissolved Ag in acidic simulant and it was found that migrated Ag was predominantly in Ag + form, with a small fraction of non-ionic AgNPs. Thus, it has been found that the amount of migrated Ag in baby products was low; however, the migration was dependent on the type of food simulant and polymer nature.

  14. Natural Product Anacardic Acid from Cashew Nut Shells Stimulates Neutrophil Extracellular Trap Production and Bactericidal Activity.

    PubMed

    Hollands, Andrew; Corriden, Ross; Gysler, Gabriela; Dahesh, Samira; Olson, Joshua; Raza Ali, Syed; Kunkel, Maya T; Lin, Ann E; Forli, Stefano; Newton, Alexandra C; Kumar, Geetha B; Nair, Bipin G; Perry, J Jefferson P; Nizet, Victor

    2016-07-01

    Emerging antibiotic resistance among pathogenic bacteria is an issue of great clinical importance, and new approaches to therapy are urgently needed. Anacardic acid, the primary active component of cashew nut shell extract, is a natural product used in the treatment of a variety of medical conditions, including infectious abscesses. Here, we investigate the effects of this natural product on the function of human neutrophils. We find that anacardic acid stimulates the production of reactive oxygen species and neutrophil extracellular traps, two mechanisms utilized by neutrophils to kill invading bacteria. Molecular modeling and pharmacological inhibitor studies suggest anacardic acid stimulation of neutrophils occurs in a PI3K-dependent manner through activation of surface-expressed G protein-coupled sphingosine-1-phosphate receptors. Neutrophil extracellular traps produced in response to anacardic acid are bactericidal and complement select direct antimicrobial activities of the compound. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

  15. Adaptation and Transcriptome Analysis of Aureobasidium pullulans in Corncob Hydrolysate for Increased Inhibitor Tolerance to Malic Acid Production

    PubMed Central

    Zou, Xiang; Wang, Yongkang; Tu, Guangwei; Zan, Zhanquan; Wu, Xiaoyan

    2015-01-01

    Malic acid is a dicarboxylic acid widely used in the food industry, and is also a potential C4 platform chemical. Corncob is a low-cost renewable feedstock from agricultural industry. However, side-reaction products (furfural, 5-hydroxymethylfurfural (HMF), formic acid, and acetic acid) that severely hinder fermentation are formed during corncob pretreatment. The process for producing malic acid from a hydrolysate of corncob was investigated with a polymalic acid (PMA)-producing Aureobasidium pullulans strain. Under the optimal hydrolysate sugar concentration 110 g/L, A. pullulans was further adapted in an aerobic fibrous bed bioreactor (AFBB) by gradually increasing the sugar concentration of hydrolysate. After nine batches of fermentation, the production and productivity of malic acid reached 38.6 g/L and 0.4 g/L h, respectively, which was higher than that in the first batch (27.6 g/L and 0.29 g/L h, respectively). The adapted strain could grow under the stress of 0.5 g/L furfural, 3 g/L HMF, 2g/L acetic acid, and 0.5 g/L formic acid, whereas the wild type did not. Transcriptome analysis revealed that the differentially expressed genes were related to carbohydrate transport and metabolism, lipid transport and metabolism, signal transduction mechanism, redox metabolism, and energy production and conversion under 0.5 g/L furfural and 3 g/L HMF stress conditions. In total, 42 genes in the adapted strain were upregulated by 15-fold or more, and qRT-PCR also confirmed that the expression levels of key genes (i.e. SIR, GSS, CYS, and GSR) involved in sulfur assimilation pathway were upregulated by over 10-fold in adapted strain for cellular protection against oxidative stress. PMID:25793624

  16. Fungal Peptaibiotics: Assessing Potential Meteoritic Amino Acid Contamination

    NASA Technical Reports Server (NTRS)

    Elsila, J. E.; Callahan, M. P.; Glavin, D. P.; Dworkin, J. P.; Bruckner, H.

    2010-01-01

    The presence of non-protein alpha-dialkyl-amino acids such as alpha-aminoisobutyric acid (alpha-A1B) and isovaline (Iva), which are relatively rare in the terrestrial biosphere, has long been used as an indication of the indigeneity of meteoritic amino acids, however, the discovery of alpha-AIB in peptides producers by a widespread group of filamentous fungi indicates the possibility of a terrestrial biotic source for the alpha-AIB observed in some meteorites. The alpha-AIB-containing peptides produced by these fungi are dubbed peptaibiotics. We measured the molecular distribution and stable carbon and nitrogen isotopic ratios for amino acids found in the total hydrolysates of four biologically synthesized peptaibiotics. We compared these aneasurenetts with those from the CM2 carbonaceous chondrite Murchison and from three Antarctic CR2 carbonaceous chondrites in order to understand the peptaibiotics as a potential source of meteoritic contamination.

  17. Feeding nitrate and docosahexaenoic acid affects enteric methane production and milk fatty acid composition in lactating dairy cows.

    PubMed

    Klop, G; Hatew, B; Bannink, A; Dijkstra, J

    2016-02-01

    An experiment was conducted to study potential interaction between the effects of feeding nitrate and docosahexaenoic acid (DHA; C22:6 n-3) on enteric CH4 production and performance of lactating dairy cows. Twenty-eight lactating Holstein dairy cows were grouped into 7 blocks of 4 cows. Within blocks, cows were randomly assigned to 1 of 4 treatments: control (CON; urea as alternative nonprotein N source to nitrate), NO3 [21 g of nitrate/kg of dry matter (DM)], DHA (3 g of DHA/kg of DM and urea as alternative nonprotein N source to nitrate), or NO3 + DHA (21 g of nitrate/kg of DM and 3 g of DHA/kg of DM, respectively). Cows were fed a total mixed ration consisting of 21% grass silage, 49% corn silage, and 30% concentrates on a DM basis. Feed additives were included in the concentrates. Cows assigned to a treatment including nitrate were gradually adapted to the treatment dose of nitrate over a period of 21 d during which no DHA was fed. The experimental period lasted 17 d, and CH4 production was measured during the last 5d in climate respiration chambers. Cows produced on average 363, 263, 369, and 298 g of CH4/d on CON, NO3, DHA, and NO3 + DHA treatments, respectively, and a tendency for a nitrate × DHA interaction effect was found where the CH4-mitigating effect of nitrate decreased when combined with DHA. This tendency was not obtained for CH4 production relative to dry matter intake (DMI) or to fat- and protein corrected milk (FPCM). The NO3 treatment decreased CH4 production irrespective of the unit in which it was expressed, whereas DHA did not affect CH4 production per kilogram of DMI, but resulted in a higher CH4 production per kilogram of fat- and protein-corrected milk (FPCM) production. The FPCM production (27.9, 24.7, 24.2, and 23. 8 kg/d for CON, NO3, DHA, and NO3 + DHA, respectively) was lower for DHA-fed cows because of decreased milk fat concentration. The proportion of saturated fatty acids in milk fat was decreased by DHA, and the proportion of

  18. Detection and Quantification of Valerenic Acid in Commercially Available Valerian Products

    ERIC Educational Resources Information Center

    Douglas, Ruth H.; Muldowney, Ciaran A.; Mohamed, Rabab; Keohane, Fiona; Shanahan, Catherine; Walsh, John J.; Kavanagh, Pierce V.

    2007-01-01

    Several valerian-containing products sold in pharmacies were evaluated to verify the presence of Valeriana officinalis by identifying the presence of valerenic acid found only in species of Valeriana. The content of valerenic acid was found to vary considerably in the products analyzed, thus emphasizing the importance of standardizing herbal…

  19. Immobilization of Actinobacillus succinogenes by adhesion or entrapment for the production of succinic acid.

    PubMed

    Corona-González, Rosa Isela; Miramontes-Murillo, Ricardo; Arriola-Guevara, Enrique; Guatemala-Morales, Guadalupe; Toriz, Guillermo; Pelayo-Ortiz, Carlos

    2014-07-01

    The production of succinic acid was studied with entrapped and adsorbed Actinobacillus succinogenes. The adsorption of fermentation products (organic acids in the concentration range of 1-20 g/L) on different supports was evaluated. It was found that succinic acid was adsorbed in small quantities on diatomite and zeolite (12.6 mg/g support). The highest production of succinic acid was achieved with A. succinogenes entrapped in agar beads. Batch fermentations with immobilized cells were carried out with glucose concentrations ranging from 20 to 80 g/L. Succinic acid (43.4 g/L) was obtained from 78.3g/L glucose, and a high productivity (2.83 g/Lh) was obtained with a glucose concentration of 37.6g/L. For repeated batch fermentations (5 cycles in 72 h) with immobilized cells in agar, the total glucose consumed was 147.55 g/L, while the production of succinic acid was 107 g/L. Immobilized cells reduced significantly the fermentation time, yield, productivity and final concentration of succinic acid. Copyright © 2014 Elsevier Ltd. All rights reserved.

  20. Kinetic study on ferulic acid production from banana stem waste via mechanical extraction

    NASA Astrophysics Data System (ADS)

    Zainol, Norazwina; Masngut, Nasratun; Khairi Jusup, Muhamad

    2018-04-01

    Banana is the tropical plants associated with lots of medicinal properties. It has been reported to be a potential source of phenolic compounds such as ferulic acid (FA). FA has excellent antioxidant properties higher than vitamin C and E. FA also have a wide range of biological activities, such as antioxidant activities and anti-microbial activities. This paper presents an experimental and kinetic study on ferulic acid (FA) production from banana stem waste (BSW) via mechanical extraction. The objective of this research is to determine the kinetic parameters in the ferulic acid production. The banana stem waste was randomly collected from the local banana plantation in Felda Lepar Hilir, Pahang. The banana stem juice was mechanically extracted by using sugarcane press machine (KR3176) and further analyzed in high performance liquid chromatography. The differential and integral method was applied to determine the kinetic parameter of the extraction process and the data obtained were fitted into the 0th, 1st and 2nd order of extraction process. Based on the results, the kinetic parameter and R2 value from were 0.05 and 0.93, respectively. It was determined that the 0th kinetic order fitted the reaction processes to best represent the mechanical extraction.

  1. Evaluating the composition and processing potential of novel sources of Brazilian biomass for sustainable biorenewables production

    PubMed Central

    2014-01-01

    Background The search for promising and renewable sources of carbohydrates for the production of biofuels and other biorenewables has been stimulated by an increase in global energy demand in the face of growing concern over greenhouse gas emissions and fuel security. In particular, interest has focused on non-food lignocellulosic biomass as a potential source of abundant and sustainable feedstock for biorefineries. Here we investigate the potential of three Brazilian grasses (Panicum maximum, Pennisetum purpureum and Brachiaria brizantha), as well as bark residues from the harvesting of two commercial Eucalyptus clones (E. grandis and E. grandis x urophylla) for biofuel production, and compare these to sugarcane bagasse. The effects of hot water, acid, alkaline and sulfite pretreatments (at increasing temperatures) on the chemical composition, morphology and saccharification yields of these different biomass types were evaluated. Results The average yield (per hectare), availability and general composition of all five biomasses were compared. Compositional analyses indicate a high level of hemicellulose and lignin removal in all grass varieties (including sugarcane bagasse) after acid and alkaline pretreatment with increasing temperatures, whilst the biomasses pretreated with hot water or sulfite showed little variation from the control. For all biomasses, higher cellulose enrichment resulted from treatment with sodium hydroxide at 130°C. At 180°C, a decrease in cellulose content was observed, which is associated with high amorphous cellulose removal and 5-hydroxymethyl-furaldehyde production. Morphological analysis showed the effects of different pretreatments on the biomass surface, revealing a high production of microfibrillated cellulose on grass surfaces, after treatment with 1% sodium hydroxide at 130°C for 30 minutes. This may explain the higher hydrolysis yields resulting from these pretreatments, since these cellulosic nanoparticles can be easily

  2. Enhanced H2O2 Production at Reductive Potentials from Oxidized Boron-Doped Ultrananocrystalline Diamond Electrodes

    PubMed Central

    2017-01-01

    This work investigates the surface chemistry of H2O2 generation on a boron-doped ultrananocrystalline diamond (BD-UNCD) electrode. It is motivated by the need to efficiently disinfect liquid waste in resource constrained environments with limited electrical power. X-ray photoelectron spectroscopy was used to identify functional groups on the BD-UNCD electrode surfaces while the electrochemical potentials of generation for these functional groups were determined via cyclic voltammetry, chronocoulometry, and chronoamperometry. A colorimetric technique was employed to determine the concentration and current efficiency of H2O2 produced at different potentials. Results showed that preanodization of an as-grown BD-UNCD electrode can enhance the production of H2O2 in a strong acidic environment (pH 0.5) at reductive potentials. It is proposed that the electrogeneration of functional groups at oxidative potentials during preanodization allows for an increased current density during the successive electrolysis at reductive potentials that correlates to an enhanced production of H2O2. Through potential cycling methods, and by optimizing the applied potentials and duty cycle, the functional groups can be stabilized allowing continuous production of H2O2 more efficiently compared to static potential methods. PMID:28471651

  3. Materials and methods for efficient lactic acid production

    DOEpatents

    Zhou, Shengde; Ingram, Lonnie O& #x27; Neal; Shanmugam, Keelnatham T; Yomano, Lorraine; Grabar, Tammy B; Moore, Jonathan C

    2013-04-23

    The present invention provides derivatives of Escherichia coli constructed for the production of lactic acid. The transformed E. coli of the invention are prepared by deleting the genes that encode competing pathways followed by a growth-based selection for mutants with improved performance. These transformed E. coli are useful for providing an increased supply of lactic acid for use in food and industrial applications.

  4. Materials and methods for efficient lactic acid production

    DOEpatents

    Zhou, Shengde [Sycamore, IL; Ingram, Lonnie O'Neal [Gainesville, FL; Shanmugam, Keelnatham T [Gainesville, FL; Yomano, Lorraine [Gainesville, FL; Grabar, Tammy B [Gainesville, FL; Moore, Jonathan C [Gainesville, FL

    2009-12-08

    The present invention provides derivatives of ethanologenic Escherichia coli K011 constructed for the production of lactic acid. The transformed E. coli of the invention are prepared by deleting the genes that encode competing pathways followed by a growth-based selection for mutants with improved performance. These transformed E. coli are useful for providing an increased supply of lactic acid for use in food and industrial applications.

  5. Lactic acid production from xylose by engineered Saccharomyces cerevisiae without PDC or ADH deletion.

    PubMed

    Turner, Timothy L; Zhang, Guo-Chang; Kim, Soo Rin; Subramaniam, Vijay; Steffen, David; Skory, Christopher D; Jang, Ji Yeon; Yu, Byung Jo; Jin, Yong-Su

    2015-10-01

    Production of lactic acid from renewable sugars has received growing attention as lactic acid can be used for making renewable and bio-based plastics. However, most prior studies have focused on production of lactic acid from glucose despite that cellulosic hydrolysates contain xylose as well as glucose. Microbial strains capable of fermenting both glucose and xylose into lactic acid are needed for sustainable and economic lactic acid production. In this study, we introduced a lactic acid-producing pathway into an engineered Saccharomyces cerevisiae capable of fermenting xylose. Specifically, ldhA from the fungi Rhizopus oryzae was overexpressed under the control of the PGK1 promoter through integration of the expression cassette in the chromosome. The resulting strain exhibited a high lactate dehydrogenase activity and produced lactic acid from glucose or xylose. Interestingly, we observed that the engineered strain exhibited substrate-dependent product formation. When the engineered yeast was cultured on glucose, the major fermentation product was ethanol while lactic acid was a minor product. In contrast, the engineered yeast produced lactic acid almost exclusively when cultured on xylose under oxygen-limited conditions. The yields of ethanol and lactic acid from glucose were 0.31 g ethanol/g glucose and 0.22 g lactic acid/g glucose, respectively. On xylose, the yields of ethanol and lactic acid were <0.01 g ethanol/g xylose and 0.69 g lactic acid/g xylose, respectively. These results demonstrate that lactic acid can be produced from xylose with a high yield by S. cerevisiae without deleting pyruvate decarboxylase, and the formation patterns of fermentations can be altered by substrates.

  6. Lysine and Glutamic Acids as the End Products of Multi-response of Optimized Fermented Medium by Mucor mucedo KP736529.

    PubMed

    El-Hersh, Mohammed S; Saber, WesamEldin I A; El-Fadaly, Husain A; Mahmoud, Mohammed K

    Amino acids are important for living organisms, they acting as crucial for metabolic activities and energy generation, wherein the deficiency in these amino acids cause various physiological defects. The aim of this study is to investigate the effect of some nutritional factors on the amino acids production by Mucor mucedo KP736529 during fermentation intervals. Mucor mucedo KP736529 was selected according to proteolytic activity. Corn steep liquor and olive cake were used in the fermented medium during Placket-Burman and central composite design to maximize the production of lysine and glutamic acids. During the screening by Plackett-Burman design, olive cake and Corn Steep Liquor (CSL) had potential importance for the higher production of amino acids. The individual fractionation of total amino acids showed both lysine and glutamic as the major amino acids associated with the fermentation process. Moreover, the Central Composite Design (CCD) has been adopted to explain the interaction between olive cake and CSL on the production of lysine and glutamic acids. The model recorded significant F-value, with high values of R 2, adjusted R 2 and predicted R 2 for both lysine and glutamic, indicating the validity of the data. Solving equation for maximum production of lysine recorded theoretical levels of olive cake and CSL, being 2.58 and 1.83 g L -1, respectively, with predicting value of lysine at 1.470 μg mL -1, whereas the predicting value of glutamic acid reached 0.805 mg mL -1 at levels of 2.49 and 1.93 g L -1 from olive cake and CSL, respectively. The desirability function (D) showed the actual responses being 1.473±0.009 and 0.801±0.004 μg mL -1 for lysine and glutamic acids, respectively. The model showed adequate validity to be applied in a large-scale production of both lysine and glutamic acids.

  7. 40 CFR 721.10211 - Octadecanoic acid, reaction products with diethylenetriamine and urea, acetates.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Octadecanoic acid, reaction products... SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.10211 Octadecanoic acid, reaction... subject to reporting. (1) The chemical substance identified as octadecanoic acid, reaction products with...

  8. Oil industry waste: a potential feedstock for biodiesel production.

    PubMed

    Abbas, Javeria; Hussain, Sabir; Iqbal, Muhammad Javid; Nadeem, Habibullah; Qasim, Muhammad; Hina, Saadia; Hafeez, Farhan

    2016-08-01

    The worldwide rising energy demands and the concerns about the sustainability of fossil fuels have led to the search for some low-cost renewable fuels. In this scenario, the production of biodiesel from various vegetable and animal sources has attracted worldwide attention. The present study was conducted to evaluate the production of biodiesel from the oil industry waste following base-catalysed transesterification. The transesterification reaction gave a yield of 83.7% by 6:1 methanol/oil molar ratio, at 60°C over 80 min of reaction time in the presence of NaOH. The gas chromatographic analysis of the product showed the presence of 16 fatty acid methyl esters with linoleic and oleic acid as principal components representing about 31% and 20.7% of the total methyl esters, respectively. The fourier transform infrared spectroscopy spectrum of oil industry waste and transesterified product further confirmed the formation of methyl esters. Furthermore, the fuel properties of oil industry waste methyl esters, such as kinematic viscosity, cetane number, cloud point, pour point, flash point, acid value, sulphur content, cold filter plugging point, copper strip corrosion, density, oxidative stability, higher heating values, ash content, water content, methanol content and total glycerol content, were determined and discussed in the light of ASTM D6751 and EN 14214 biodiesel standards. Overall, this study presents the production of biodiesel from the oil industry waste as an approach of recycling this waste into value-added products.

  9. Beech wood Fagus sylvatica dilute-acid hydrolysate as a feedstock to support Chlorella sorokiniana biomass, fatty acid and pigment production.

    PubMed

    Miazek, Krystian; Remacle, Claire; Richel, Aurore; Goffin, Dorothee

    2017-04-01

    This work evaluates the possibility of using beech wood (Fagus sylvatica) dilute-acid (H 2 SO 4 ) hydrolysate as a feedstock for Chlorella sorokiniana growth, fatty acid and pigment production. Neutralized wood acid hydrolysate, containing organic and mineral compounds, was tested on Chlorella growth at different concentrations and compared to growth under phototrophic conditions. Chlorella growth was improved at lower loadings and inhibited at higher loadings. Based on these results, a 12% neutralized wood acid hydrolysate (Hyd12%) loading was selected to investigate its impact on Chlorella growth, fatty acid and pigment production. Hyd12% improved microalgal biomass, fatty acid and pigment productivities both in light and in dark, when compared to photoautotrophic control. Light intensity had substantial influence on fatty acid and pigment composition in Chlorella culture during Hyd12%-based growth. Moreover, heterotrophic Chlorella cultivation with Hyd12% also showed that wood hydrolysate can constitute an attractive feedstock for microalgae cultivation in case of lack of light. Copyright © 2017 Elsevier Ltd. All rights reserved.

  10. Discovery of a Phosphonoacetic Acid Derived Natural Product by Pathway Refactoring.

    PubMed

    Freestone, Todd S; Ju, Kou-San; Wang, Bin; Zhao, Huimin

    2017-02-17

    The activation of silent natural product gene clusters is a synthetic biology problem of great interest. As the rate at which gene clusters are identified outpaces the discovery rate of new molecules, this unknown chemical space is rapidly growing, as too are the rewards for developing technologies to exploit it. One class of natural products that has been underrepresented is phosphonic acids, which have important medical and agricultural uses. Hundreds of phosphonic acid biosynthetic gene clusters have been identified encoding for unknown molecules. Although methods exist to elicit secondary metabolite gene clusters in native hosts, they require the strain to be amenable to genetic manipulation. One method to circumvent this is pathway refactoring, which we implemented in an effort to discover new phosphonic acids from a gene cluster from Streptomyces sp. strain NRRL F-525. By reengineering this cluster for expression in the production host Streptomyces lividans, utility of refactoring is demonstrated with the isolation of a novel phosphonic acid, O-phosphonoacetic acid serine, and the characterization of its biosynthesis. In addition, a new biosynthetic branch point is identified with a phosphonoacetaldehyde dehydrogenase, which was used to identify additional phosphonic acid gene clusters that share phosphonoacetic acid as an intermediate.

  11. Production of lactic acid from hemicellulose extracts by Bacillus coagulans MXL-9.

    PubMed

    Walton, Sara L; Bischoff, Kenneth M; van Heiningen, Adriaan R P; van Walsum, G Peter

    2010-08-01

    Bacillus coagulans MXL-9 was found capable of growing on pre-pulping hemicellulose extracts, utilizing all of the principle monosugars found in woody biomass. This organism is a moderate thermophile isolated from compost for its pentose-utilizing capabilities. It was found to have high tolerance for inhibitors such as acetic acid and sodium, which are present in pre-pulping hemicellulose extracts. Fermentation of 20 g/l xylose in the presence of 30 g/l acetic acid required a longer lag phase but overall lactic acid yield was not diminished. Similarly, fermentation of xylose in the presence of 20 g/l sodium increased the lag time but did not affect overall product yield, though 30 g/l sodium proved completely inhibitory. Fermentation of hot water-extracted Siberian larch containing 45 g/l total monosaccharides, mainly galactose and arabinose, produced 33 g/l lactic acid in 60 h and completely consumed all sugars. Small amounts of co-products were formed, including acetic acid, formic acid, and ethanol. Hemicellulose extract formed during autohydrolysis of mixed hardwoods contained mainly xylose and was converted into lactic acid with a 94% yield. Green liquor-extracted hardwood hemicellulose containing 10 g/l acetic acid and 6 g/l sodium was also completely converted into lactic acid at a 72% yield. The Bacillus coagulans MXL-9 strain was found to be well suited to production of lactic acid from lignocellulosic biomass due to its compatibility with conditions favorable to industrial enzymes and its ability to withstand inhibitors while rapidly consuming all pentose and hexose sugars of interest at high product yields.

  12. Production of gaba (γ - Aminobutyric acid) by microorganisms: a review.

    PubMed

    Dhakal, Radhika; Bajpai, Vivek K; Baek, Kwang-Hyun

    2012-10-01

    GABA (γ-aminobutyric acid) is a four carbon non-protein amino acid that is widely distributed in plants, animals and microorganisms. As a metabolic product of plants and microorganisms produced by the decarboxylation of glutamic acid, GABA functions as an inhibitory neurotransmitter in the brain that directly affects the personality and the stress management. A wide range of traditional foods produced by microbial fermentation contain GABA, in which GABA is safe and eco-friendly, and also has the possibility of providing new health-benefited products enriched with GABA. Synthesis of GABA is catalyzed by glutamate decarboxylase, therefore, the optimal fermentation condition is mainly based on the biochemical properties of the enzyme. Major GABA producing microorganisms are lactic acid bacteria (LAB), which make food spoilage pathogens unable to grow and act as probiotics in the gastrointestinal tract. The major factors affecting the production of GABA by microbial fermentation are temperature, pH, fermentation time and different media additives, therefore, these factors are summarized to provide the most up-dated information for effective GABA synthesis. There has been a huge accumulation of knowledge on GABA application for human health accompanying with a demand on natural GABA supply. Only the GABA production by microorganisms can fulfill the demand with GABA-enriched health beneficial foods.

  13. The oleic acid-ozone heterogeneous reaction system: products, kinetics, secondary chemistry, and atmospheric implications of a model system a review

    NASA Astrophysics Data System (ADS)

    Zahardis, J.; Petrucci, G. A.

    2006-11-01

    The heterogeneous processing of organic aerosols by trace oxidants has many implications to atmospheric chemistry and climate regulation. This review covers a model heterogeneous reaction system (HRS): the oleic acid-ozone HRS and other reaction systems featuring fatty acids, and their derivatives. The analysis of the primary products of ozonolysis (azelaic acid, nonanoic acid, 9-oxononanoic acid, nonanal) is described. Anomalies in the relative product yields are noted and explained by the observation of secondary chemical reactions. The secondary reaction products arising from reactive Criegee intermediates are mainly peroxidic, notably secondary ozonides and α-acyloxyalkyl hydroperoxide polymers. These highly oxygenated products are of low volatility and hydrophilic which may enhance the ability of particles to act as cloud condensation nuclei. The kinetic description of this HRS is critically reviewed. Most kinetic studies suggest this oxidative processing is either a near surface reaction that is limited by the diffusion of ozone or a surface based reaction. Internally mixed particles and coatings represent the next stage in the progression towards more realistic proxies of tropospheric organic aerosols and a description of the products and the kinetics resulting from the ozonolysis of these proxies, which are based on fatty acids or their derivatives, is presented. Finally, a series of atmospheric implications of oxidative processing of particulate containing fatty acids is presented. These implications include the extended lifetime of unsaturated species in the troposphere facilitated by the presence of solids, semisolids or viscous phases, and an enhanced rate of ozone uptake by particulate unsaturates compared to corresponding gas phase organics. Ozonolysis of oleic acid enhances its CCN activity, which implies that oxidatively processed particulate may contribute to indirect forcing of radiation. Other effects, including the potential role of aldehydic

  14. Production of lactic acid from sucrose: strain selection, fermentation, and kinetic modeling.

    PubMed

    Lunelli, Betânia H; Andrade, Rafael R; Atala, Daniel I P; Wolf Maciel, Maria Regina; Maugeri Filho, Francisco; Maciel Filho, Rubens

    2010-05-01

    Lactic acid is an important product arising from the anaerobic fermentation of sugars. It is used in the pharmaceutical, cosmetic, chemical, and food industries as well as for biodegradable polymer and green solvent production. In this work, several bacterial strains were isolated from industrial ethanol fermentation, and the most efficient strain for lactic acid production was selected. The fermentation was conducted in a batch system under anaerobic conditions for 50 h at a temperature of 34 degrees C, a pH value of 5.0, and an initial sucrose concentration of 12 g/L using diluted sugarcane molasses. Throughout the process, pulses of molasses were added in order to avoid the cell growth inhibition due to high sugar concentration as well as increased lactic acid concentrations. At the end of the fermentation, about 90% of sucrose was consumed to produce lactic acid and cells. A kinetic model has been developed to simulate the batch lactic acid fermentation results. The data obtained from the fermentation were used for determining the kinetic parameters of the model. The developed model for lactic acid production, growth cell, and sugar consumption simulates the experimental data well.

  15. Prevention of volatile fatty acids production and limitation of odours from winery wastewaters by denitrification.

    PubMed

    Bories, André; Guillot, Jean-Michel; Sire, Yannick; Couderc, Marie; Lemaire, Sophie-Andréa; Kreim, Virginie; Roux, Jean-Claude

    2007-07-01

    The effect of the addition of nitrate to winery wastewaters to control the formation of VFA in order to prevent odours during storage and treatment was studied in batch bioreactors at different NO(3)/chemical oxygen demand (COD) ratios and at full scale in natural evaporation ponds (2 x 7000 m(2)) by measuring olfactory intensity. In the absence of nitrate, butyric acid (2304 mgL(-1)), acetic acid (1633 mgL(-1)), propionic acid (1558 mgL(-1)), caproic acid (499 mgL(-1)) and valeric acid (298 mgL(-1)) were produced from reconstituted winery wastewater. For a ratio of NO(3)/COD=0.4 gg(-1), caproic and valeric acids were not formed. The production of butyric and propionic acids was reduced by 93.3% and 72.5%, respectively, at a ratio of NO(3)/COD=0.8, and by 97.4% and 100% at a ratio of NO(3)/COD=1.2 gg(-1). Nitrate delayed and decreased butyric acid formation in relation to the oxidoreduction potential. Studies in ponds showed that the addition of concentrated calcium nitrate (NITCAL) to winery wastewaters (3526 m(3)) in a ratio of NO(3)/COD=0.8 inhibited VFA production, with COD elimination (94%) and total nitrate degradation, and no final nitrite accumulation. On the contrary, in ponds not treated with nitrate, malodorous VFA (from propionic to heptanoïc acids) represented up to 60% of the COD. Olfactory intensity measurements in relation to the butanol scale of VFA solutions and the ponds revealed the pervasive role of VFA in the odour of the untreated pond as well as the clear decrease in the intensity and not unpleasant odour of the winery wastewater pond enriched in nitrates. The results obtained at full scale underscored the feasibility and safety of the calcium nitrate treatment as opposed to concentrated nitric acid.

  16. 40 CFR 721.10126 - Alkyl amino substituted triazine amino substituted benezenesulfonic acid reaction product with...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... substituted benezenesulfonic acid reaction product with naphthalenesulfonato azo substituted phenyl azo... substituted triazine amino substituted benezenesulfonic acid reaction product with naphthalenesulfonato azo... substituted triazine amino substituted benezenesulfonic acid reaction product with naphthalenesulfonato azo...

  17. 40 CFR 721.10126 - Alkyl amino substituted triazine amino substituted benezenesulfonic acid reaction product with...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... substituted benezenesulfonic acid reaction product with naphthalenesulfonato azo substituted phenyl azo... substituted triazine amino substituted benezenesulfonic acid reaction product with naphthalenesulfonato azo... substituted triazine amino substituted benezenesulfonic acid reaction product with naphthalenesulfonato azo...

  18. Influence of commercial (Fluka) naphthenic acids on acid volatile sulfide (AVS) production and divalent metal precipitation.

    PubMed

    McQueen, Andrew D; Kinley, Ciera M; Rodgers, John H; Friesen, Vanessa; Bergsveinson, Jordyn; Haakensen, Monique C

    2016-12-01

    Energy-derived waters containing naphthenic acids (NAs) are complex mixtures often comprising a suite of potentially problematic constituents (e.g. organics, metals, and metalloids) that need treatment prior to beneficial use, including release to receiving aquatic systems. It has previously been suggested that NAs can have biostatic or biocidal properties that could inhibit microbially driven processes (e.g. dissimilatory sulfate reduction) used to transfer or transform metals in passive treatment systems (i.e. constructed wetlands). The overall objective of this study was to measure the effects of a commercially available (Fluka) NA on sulfate-reducing bacteria (SRB), production of sulfides (as acid-volatile sulfides [AVS]), and precipitation of divalent metals (i.e. Cu, Ni, Zn). These endpoints were assessed following 21-d aqueous exposures of NAs using bench-scale reactors. After 21-days, AVS molar concentrations were not statistically different (p<0.0001; α=0.05) among NA treatments (10, 20, 40, 60, and 80mg NA/L) and an untreated control (no NAs). Extent of AVS production was sufficient in all NA treatments to achieve ∑SEM:AVS <1, indicating that conditions were conducive for treatment of metals, with sulfide ligands in excess of SEM (Cu, Ni, and Zn). In addition, no adverse effects to SRB (in terms of density, relative abundance, and diversity) were measured following exposures of a commercial NA. In this bench-scale study, dissimilatory sulfate reduction and subsequent metal precipitation were not vulnerable to NAs, indicating passive treatment systems utilizing sulfide production (AVS) could be used to treat metals occurring in NAs affected waters. Copyright © 2016 Elsevier Inc. All rights reserved.

  19. Polymalic acid fermentation by Aureobasidium pullulans for malic acid production from soybean hull and soy molasses: Fermentation kinetics and economic analysis.

    PubMed

    Cheng, Chi; Zhou, Yipin; Lin, Meng; Wei, Peilian; Yang, Shang-Tian

    2017-01-01

    Polymalic acid (PMA) production by Aureobasidium pullulans ZX-10 from soybean hull hydrolysate supplemented with corn steep liquor (CSL) gave a malic acid yield of ∼0.4g/g at a productivity of ∼0.5g/L·h. ZX-10 can also ferment soy molasses, converting all carbohydrates including the raffinose family oligosaccharides to PMA, giving a high titer (71.9g/L) and yield (0.69g/g) at a productivity of 0.29g/L·h in fed-batch fermentation under nitrogen limitation. A higher productivity of 0.64g/L·h was obtained in repeated batch fermentation with cell recycle and CSL supplementation. Cost analysis for a 5000 MT plant shows that malic acid can be produced at $1.10/kg from soy molasses, $1.37/kg from corn, and $1.74/kg from soybean hull. At the market price of $1.75/kg, malic acid production from soy molasses via PMA fermentation offers an economically competitive process for industrial production of bio-based malic acid. Copyright © 2016 Elsevier Ltd. All rights reserved.

  20. Production of docosahexaenoic acid by Aurantiochytrium sp. ATCC PRA-276.

    PubMed

    Furlan, Valcenir Júnior Mendes; Maus, Victor; Batista, Irineu; Bandarra, Narcisa Maria

    The high costs and environmental concerns associated with using marine resources as sources of oils rich in polyunsaturated fatty acids have prompted searches for alternative sources of such oils. Some microorganisms, among them members of the genus Aurantiochytrium, can synthesize large amounts of these biocompounds. However, various parameters that affect the polyunsaturated fatty acids production of these organisms, such as the carbon and nitrogen sources supplied during their cultivation, require further elucidation. The objective of this investigation was to study the effect of different concentrations of carbon and total nitrogen on the production of polyunsaturated fatty acids, particularly docosahexaenoic acid, by Aurantiochytrium sp. ATCC PRA-276. We performed batch system experiments using an initial glucose concentration of 30g/L and three different concentrations of total nitrogen, including 3.0, 0.44, and 0.22g/L, and fed-batch system experiments in which 0.14g/L of glucose and 0.0014g/L of total nitrogen were supplied hourly. To assess the effects of these different treatments, we determined the biomass, glucose, total nitrogen and polyunsaturated fatty acids concentration. The maximum cell concentration (23.9g/L) was obtained after 96h of cultivation in the batch system using initial concentrations of 0.22g/L total nitrogen and 30g/L glucose. Under these conditions, we observed the highest level of polyunsaturated fatty acids production (3.6g/L), with docosahexaenoic acid and docosapentaenoic acid ω6 concentrations reaching 2.54 and 0.80g/L, respectively. Copyright © 2017 Sociedade Brasileira de Microbiologia. Published by Elsevier Editora Ltda. All rights reserved.

  1. Anaerobic microbial dissolution of lead and production of organic acids

    DOEpatents

    Francis, A.J.; Dodge, C.; Chendrayan, K.; Quinby, H.L.

    1987-04-16

    The present invention related to an anaerobic bacterial culture of Clostridium sp. ATCC No. 53464 which solubilizes lead oxide under anaerobic conditions in coal and industrial wastes and therefore presents a method of removing lead from such wastes before they are dumped into the environment. The rat of lead dissolution during logarithmic growth of the bacteria in 40 ml medium containing 3.32 ..mu..moles of lead as lead oxide was 0.042 ..mu..moles m1/sup /-/1/ hr/sup /-/1/. Dissolution of lead oxide by the bacterial isolate is due to the production of metabolites and acidity in the culture medium. The major metabolites are acetic, butyric and lactic acid. The major metabolites are acetic, butyric and lactic acid. Clostridium sp. ATCC No. 53464 can be used in the recovery of the strategic metals from ores and wastes and also for the production of lactic acid for commercial purposes. The process yields large quantities of lactic acid as well as lead complexed in a stable form with said acids. 4 figs., 3 tabs.

  2. A novel extractive fermentation process for propionic acid production from whey lactose

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

    Lewis, V.P.; Yang, Shangtian

    An extractive fermentation process was developed to produce propionate from lactose. The bacterium Propionibacterium acidipropionici was immobilized in a spiral wound, fibrous matrix packed in the reactor. Propionic acid is the major product from lactose fermentation, with acetic acid and carbon dioxide as byproducts. Propionic acid is a strong inhibitor to this fermentation. A tertiary amine was used to selectively extract propionic acid from the bioreactor, hence enhancing reactor productivity by over 100%. The authors also speculate that by selectively extracting propionic acid, lactose metabolism can be directed to yield more propionate and less byproducts. Other advantages of extractive fermentationmore » include better pH control and a purer product. The propionic acid present in the extractant can be easily stripped with small amounts of an alkaline solution, resulting in a concentrated propionate salt. The extractant was also regenerated in this stripping step. Thus, the process is energy-efficient and economically attractive.« less

  3. Establishment and assessment of an integrated citric acid-methane production process.

    PubMed

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

    2015-01-01

    To solve the problem of extraction wastewater in citric acid industrial production, an improved integrated citric acid-methane production process was established in this study. Extraction wastewater was treated by anaerobic digestion and then the anaerobic digestion effluent (ADE) was stripped by air to remove ammonia. Followed by solid-liquid separation to remove metal ion precipitation, the supernatant was recycled for the next batch of citric acid fermentation, thus eliminating wastewater discharge and reducing water consumption. 130U/g glucoamylase was added to medium after inoculation and the recycling process performed for 10 batches. Fermentation time decreased by 20% in recycling and the average citric acid production (2nd-10th) was 145.9±3.4g/L, only 2.5% lower than that with tap water (149.6g/L). The average methane production was 292.3±25.1mL/g CODremoved and stable in operation. Excessive Na(+) concentration in ADE was confirmed to be the major challenge for the proposed process. Copyright © 2014 Elsevier Ltd. All rights reserved.

  4. Microwave-assisted extraction and purification of chlorogenic acid from by-products of Eucommia Ulmoides Oliver and its potential anti-tumor activity.

    PubMed

    Shao, P; Zhang, J F; Chen, X X; Sun, P L

    2015-08-01

    An efficient method for the rapid extraction, separation and purification of chlorogenic acid (CGA) from by-products of Eucommia Ulmoides Oliver (E. ulmoides) by microwave-assisted extraction (MAE) coupled with high-speed counter-current chromatography (HSCCC) was developed. The optimal MAE parameters were evaluated by response surface methodology (RSM), and they were extraction time of 12 min, microwave power of 420 W, ethanol concentration of 75 %, solvent/sample ratio of 30:1 (mL/g), yield of CGA reached 3.59 %. The crude extract was separated and purified directly by HSCCC using ethyl acetate-butyl alcohol-water (3:1:4, v/v) as the two-phase solvent system. The 14.5 mg of CGA with the purity of 98.7 % was obtained in one-step separation from 400 mg of crude extract. The chemical structure of CGA was verified with IR, ESI-MS analysis. Meanwhile, the purified CGA extract was evaluated by MTT assay and results indicate that CGA extract exhibited potential anti-tumor activity for AGS gastric cancer cell.

  5. Anaerobic microbial dissolution of lead and production of organic acids

    DOEpatents

    Francis, Arokiasamy J.; Dodge, Cleveland; Chendrayan, Krishnachetty; Quinby, Helen L.

    1988-01-01

    The present invention relates to an anaerobic bacterial culture of Clostridium sp. ATCC No. 53464 which solubilizes lead oxide under anaerobic conditions in coal and industrial wastes and therefore presents a method of removing lead from such wastes before they are dumped into the environment. The rate of lead dissolution during logarithmic growth of the bacteria in 40 ml medium containing 3.32 .mu.moles of lead as lead oxide was 0.042 .mu.moles ml.sup.-1 hr.sup.-1. Dissolution of lead oxide by the bacterial isolate is due to the production of metabolites and acidity in the culture medium. The major metabolites are acetic, butyric and lactic acid. Clostridium sp. ATCC No. 53464 can be used in the recovery of strategic metals from ores and wastes and also for the production of lactic acid for commercial purposes. The process yields large quantities of lactic acid as well as lead complexed in a stable form with said acids.

  6. Microwave-assisted biodiesel production by esterification of palm fatty acid distillate.

    PubMed

    Lokman, Ibrahim M; Rashid, Umer; Zainal, Zulkarnain; Yunus, Robiah; Taufiq-Yap, Yun Hin

    2014-01-01

    In the current research work, effect of microwave irradiation energy on the esterification of palm fatty acid distillate (PFAD) to produce PFAD methyl ester / biodiesel was intensively appraised. The PFAD is a by-product from refinery of crude palm oil consisting >85% of free fatty acid (FFA). The esterification reaction process with acid catalyst is needed to convert the FFA into fatty acid methyl ester or known as biodiesel. In this work, fabricated microwave-pulse width modulation (MPWM) reactor with controlled temperature was designed to be capable to increase the PFAD biodiesel production rate. The classical optimization technique was used in order to study the relationship and the optimum condition of variables involved. Consequently, by using MPWM reactor, mixture of methanol-to-PFAD molar ratio of 9:1, 1 wt.% of sulfuric acid catalyst, at 55°C reaction temperature within 15 min reaction time gave 99.5% of FFA conversion. The quality assessment and properties of the product were analyzed according to the American Society for Testing and Materials (ASTM), European (EN) standard methods and all results were in agreement with the standard requirements. It revealed that the use of fabricated MPWM with controlled temperature was significantly affecting the rate of esterification reaction and also increased the production yield of PFAD methyl ester.

  7. The Effect of Acid Pre-Treatment using Acetic Acid and Nitric Acid in The Production of Biogas from Rice Husk during Solid State Anaerobic Digestion (SS-AD)

    NASA Astrophysics Data System (ADS)

    Nugraha, Winardi Dwi; Syafrudin; Keumala, Cut Fadhila; Matin, Hasfi Hawali Abdul; Budiyono

    2018-02-01

    Pretreatment during biogas production aims to assist in degradation of lignin contained in the rice husk. In this study, pretreatment which is used are acid and biological pretreatment. Acid pretreatment was performed using acetic acid and nitric acid with a variety levels of 3% and 5%. While biological pretreatment as a control variable. Acid pretreatment was conducted by soaking the rice straw for 24 hours with acid variation. The study was conducted using Solid State Anaerobic Digestion (SS-AD) with 21% TS. Biogas production was measured using water displacement method every two days for 60 days at room temperature conditions. The results showed that acid pretreatment gave an effect on the production of biogas yield. The yield of the biogas produced by pretreatment of acetic acid of 5% and 3% was 43.28 and 45.86 ml/gr.TS. While the results without pretreatment biogas yield was 29.51 ml/gr.TS. The results yield biogas produced by pretreatment using nitric acid of 5% and 3% was 12.14 ml/gr.TS and 21.85 ml/gr.TS. Results biogas yield with acetic acid pretreatment was better than the biogas yield results with nitric acid pretreatment.

  8. Distribution of fatty acids and phospholipids in different table cuts and co-products from New Zealand pasture-fed Wagyu-dairy cross beef cattle.

    PubMed

    Bermingham, Emma N; Reis, Mariza Gomes; Subbaraj, Arvind K; Cameron-Smith, David; Fraser, Karl; Jonker, Arjan; Craigie, Cameron R

    2018-06-01

    Wagyu beef products are marketed as luxury goods to discerning consumers and the lipid content and composition are important drivers of wagyu product value. Wagyu beef is an extensively marbled meat product, well characterised for its tenderness and flavour. In New Zealand, pasture-fed Wagyu-dairy beef production is increasing to meet demand for ultra-premium meat products. Important for these characteristics is the composition of lipid species and their distribution across the carcass. The aim of this study was to analyse the distribution of fatty acids and phospholipids in 26 table cuts, nine co-products and three fat deposits of carcasses from New Zealand pasture-fed Wagyu-dairy cross beef carcasses (n = 5). Phospholipid and fatty acid levels varied across different cuts of the carcass, but typically cuts with high levels of phospholipids also had high levels of omega-3 fatty acids and low levels of saturated fatty acids. This work will be used in the future to examine the potential health aspects of pasture-fed Wagyu beef. Copyright © 2018 Elsevier Ltd. All rights reserved.

  9. Value of acid metabolic products in identification of certain corynebacteria.

    PubMed Central

    Reddy, C A; Kao, M

    1978-01-01

    Acid metabolic products of 23 strains of human and animal pathogenic corynebacteria, representing eight different species, were determined by gas chromatography. The results showed that the species examined were metabolically heterogeneous and could be presumptively identified based on the acid products produced. Corynebacterium equi did not produce any acids; C. renale produced lactate; and C. pyogenes produced major amounts of lactate, variable amounts of acetate, and minor amounts of succinate and pyruvate. C. kutscheri produced propionate and lactate as major products and pyruvate and oxalacetate as minor products. C. diphtheriae and C. pseudotuberculosis produced major amounts of propionate, acetate, and formate. In addition, C. pseudotuberculosis produced major amounts of pyruvate and minor amounts of succinate, lactate, and oxalacetate, whereas C. diphtheriae strains produced minor but variable amounts of lactate, succinate, fumarate, pyruvate, and oxalacetate. C. bovis produced aicd products similar to those of C. pyogenes but was readily distinguishable from the latter by the lack of hemolysis on blood agar, colony morphology, catalase reaction, and biochemicals. C. suis characteristically produced major amounts of ethanol, acetate, and formate and minor amounts of lactate and succinate but no propionate. PMID:96126

  10. Phenolic acids potentiate colistin-mediated killing of Acinetobacter baumannii by inducing redox imbalance.

    PubMed

    Ajiboye, Taofeek O; Skiebe, Evelyn; Wilharm, Gottfried

    2018-05-01

    Phenolic acids with catechol groups are good prooxidants because of their low redox potential. In this study, we provided data showing that phenolic acids, caffeic acid, gallic acid and protocatechuic acid, enhanced colistin-mediated bacterial death by inducing redox imbalance. The minimum inhibitory concentrations of these phenolic acids against Acinetobacter baumannii AB5075 were considerably lowered for ΔsodB and ΔkatG mutants. Checkerboard assay shows synergistic interactions between colistin and phenolic acids. The phenolic acids exacerbated colistin-induced oxidative stress in A. baumannii AB5075 through increased superoxide anion generation, NAD + /NADH and ADP/ATP ratio. In parallel, the level of reduced glutathione was significantly lowered. We conclude that phenolic acids potentiate colistin-induced oxidative stress in A. baumannii AB5075 by increasing ROS generation, energy metabolism and electron transport chain activity with a concomitant decrease in glutathione. Copyright © 2018 Elsevier Masson SAS. All rights reserved.

  11. Highly efficient production of D-lactic acid from chicory-derived inulin by Lactobacillus bulgaricus.

    PubMed

    Xu, Qianqian; Zang, Ying; Zhou, Jie; Liu, Peng; Li, Xin; Yong, Qiang; Ouyang, Jia

    2016-11-01

    Inulin is a readily available feedstock for cost-effective production of biochemicals. To date, several studies have explored the production of bioethanol, high-fructose syrup and fructooligosaccharide, but there are no studies regarding the production of D-lactic acid using inulin as a carbon source. In the present study, chicory-derived inulin was used for D-lactic acid biosynthesis by Lactobacillus bulgaricus CGMCC 1.6970. Compared with separate hydrolysis and fermentation processes, simultaneous saccharification and fermentation (SSF) has demonstrated the best performance of D-lactic acid production. Because it prevents fructose inhibition and promotes the complete hydrolysis of inulin, the highest D-lactic acid concentration (123.6 ± 0.9 g/L) with a yield of 97.9 % was obtained from 120 g/L inulin by SSF. Moreover, SSF by L. bulgaricus CGMCC 1.6970 offered another distinct advantage with respect to the higher optical purity of D-lactic acid (>99.9 %) and reduced number of residual sugars. The excellent performance of D-lactic acid production from inulin by SSF represents a high-yield method for D-lactic acid production from non-food grains.

  12. Acidic microenvironments induce lymphangiogenesis and IL-8 production via TRPV1 activation in human lymphatic endothelial cells

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

    Nakanishi, Masako, E-mail: n-masako@wakayama-med.ac.jp; Morita, Yoshihiro; Department of Oral and Maxillofacial Surgery, Seichokai Hannan Municipal Hospital, Hannan, Osaka 599-0202

    Local acidosis is one of the characteristic features of the cancer microenvironment. Many reports indicate that acidosis accelerates the proliferation and invasiveness of cancer cells. However, whether acidic conditions affect lymphatic metastasis is currently unknown. In the present study, we focused on the effects of acidosis on lymphatic endothelial cells (LECs) to assess the relationship between acidic microenvironments and lymph node metastasis. We demonstrated that normal human LECs express various acid receptors by immunohistochemistry and reverse transcriptase-polymerase chain reaction (PCR). Acidic stimulation with low pH medium induced morphological changes in LECs to a spindle shape, and significantly promoted cellular growthmore » and tube formation. Moreover, real-time PCR revealed that acidic conditions increased the mRNA expression of interleukin (IL)-8. Acidic stimulation increased IL-8 production in LECs, whereas a selective transient receptor potential vanilloid subtype 1 (TRPV1) antagonist, 5′-iodoresiniferatoxin, decreased IL-8 production. IL-8 accelerated the proliferation of LECs, and inhibition of IL-8 diminished tube formation and cell migration. In addition, phosphorylation of nuclear factor (NF)-κB was induced by acidic conditions, and inhibition of NF-κB activation reduced acid-induced IL-8 expression. These results suggest that acidic microenvironments in tumors induce lymphangiogenesis via TRPV1 activation in LECs, which in turn may promote lymphatic metastasis. - Highlights: • Acidity accelerates the growth, migration, and tube formation of LECs. • Acidic condition induces IL-8 expression in LECs. • IL-8 is critical for the changes of LECs. • IL-8 expression is induced via TRPV1 activation.« less

  13. Production of lovastatin and itaconic acid by Aspergillus terreus: a comparative perspective.

    PubMed

    Boruta, Tomasz; Bizukojc, Marcin

    2017-02-01

    Aspergillus terreus is a textbook example of an industrially relevant filamentous fungus. It is used for the biotechnological production of two valuable metabolites, namely itaconic acid and lovastatin. Itaconic acid serves as a precursor in polymer industry, whereas lovastatin found its place in the pharmaceutical market as a cholesterol-lowering statin drug and a precursor for semisynthetic statins. Interestingly, their biosynthetic gene clusters were shown to reside in the common genetic neighborhood. Despite the genomic proximity of the underlying biosynthetic genes, the production of lovastatin and itaconic acid was shown to be favored by different factors, especially with respect to pH values of the broth. While there are several reviews on various aspects of lovastatin and itaconic acid production, the survey on growth conditions, biochemistry and morphology related to the formation of these two metabolites has never been presented in the comparative manner. The aim of the current review is to outline the correlations and contrasts with respect to process-related and biochemical discoveries regarding itaconic acid and lovastatin production by A. terreus.

  14. Potential of bacteriocin-producing lactic acid bacteria for safety improvements of traditional Thai fermented meat and human health.

    PubMed

    Swetwiwathana, Adisorn; Visessanguan, Wonnop

    2015-11-01

    Lactic acid bacteria (LAB) are very important in converting of agricultural products into safe, delicious and shelf stable foods for human consumption. The preservative activity of LAB in foods is mainly attributed to the production of anti-microbial metabolites such as organic acids and bacteriocins which enables them to grow and control the growth of pathogens and spoilage microorganisms. Besides ensuring safety, bacteriocin-producing LAB with their probiotic potentials could also be emerging as a means to develop functional meat products with desirable health benefits. Nevertheless, to be qualified as a candidate probiotic culture, other prerequisite probiotic properties of bacteriocin-producing LAB have to be assessed according to regulatory guidelines for probiotics. Nham is an indigenous fermented sausage of Thailand that has gained popularity and acceptance among Thais. Since Nham is made from raw meat and is usually consumed without cooking, risks due to undesirable microorganisms such as Salmonella spp., Staphylococcus aureus, and Listeria monocytogenes, are frequently observed. With an ultimate goal to produce safer and healthier product, our research attempts on the development of a variety of new Nham products are discussed. Copyright © 2015 Elsevier Ltd. All rights reserved.

  15. Potassium ferrate addition as an alternative pre-treatment to enhance short-chain fatty acids production from waste activated sludge.

    PubMed

    He, Zhang-Wei; Liu, Wen-Zong; Gao, Qin; Tang, Cong-Cong; Wang, Ling; Guo, Ze-Chong; Zhou, Ai-Juan; Wang, Ai-Jie

    2018-01-01

    A potentially practical technology based on ferrate (VI), i.e. potassium ferrate (PF), pretreatment integrated into waste activated sludge (WAS) anaerobic fermentation has been presented to greatly enhance short-chain fatty acids (SCFAs) production with a shortened fermentation time. The maximum production of SCFAs, 343mg chemical oxygen demand/g volatile suspended solid with acetic acid proportion of 48.2%, was obtained with PF dosage of 56mg Fe(VI)/g total suspended solid within 5days, which was increased to 5.72times compared to that of control. The mechanism study showed that PF accelerated the release rate of both intracellular and extracellular constituents. And the activities of key hydrolytic enzymes were much improved with PF addition. Moreover, PF positively enriched the abundance of microorganisms responsible for WAS hydrolysis and SCFAs production, especially acetic acid-forming characteristic genera such as Petrimonas, Fusibacter and Acetoanaerobium. Besides, the incubation time of acidogenesis and methanogenesis were separated by PF. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Fumaric acid production in Saccharomyces cerevisiae by simultaneous use of oxidative and reductive routes.

    PubMed

    Xu, Guoqiang; Chen, Xiulai; Liu, Liming; Jiang, Linghuo

    2013-11-01

    In this study, the simultaneous use of reductive and oxidative routes to produce fumaric acid was explored. The strain FMME003 (Saccharomyces cerevisiae CEN.PK2-1CΔTHI2) exhibited capability to accumulate pyruvate and was used for fumaric acid production. The fum1 mutant FMME004 could produce fumaric acid via oxidative route, but the introduction of reductive route derived from Rhizopus oryzae NRRL 1526 led to lower fumaric acid production. Analysis of the key factors associated with fumaric acid production revealed that pyruvate carboxylase had a low degree of control over the carbon flow to malic acid. The fumaric acid titer was improved dramatically when the heterologous gene RoPYC was overexpressed and 32 μg/L of biotin was added. Furthermore, under the optimal carbon/nitrogen ratio, the engineered strain FMME004-6 could produce up to 5.64 ± 0.16 g/L of fumaric acid. These results demonstrated that the proposed fermentative method is efficient for fumaric acid production. Copyright © 2013 Elsevier Ltd. All rights reserved.

  17. Production of pyroglutamic acid by thermophilic lactic acid bacteria in hard-cooked mini-cheeses.

    PubMed

    Mucchetti, G; Locci, F; Massara, P; Vitale, R; Neviani, E

    2002-10-01

    Pyroglutamic acid is present in high amounts (0.5g/ 100g) in many cheese varieties-and particularly in extensively ripened Italian cheeses such as Grana Padano and Parmigiano Reggiano. An in vivo model system for cooked mini-cheese production and ripening acceleration was set up to demonstrate the ability of thermophilic lactic acid bacteria, used as a starter, to produce pyroglutamic acid (pGlu). In mini-cheeses stored at 38 and 30 degrees C for up to 45 d, all starters tested produced different amounts of pGlu. In descending order of pGlu production, the bacteria analyzed were: Lactobacillus helveticus, Lactobacillus delbrueckii subsp. bulgaricus, Streptococcus thermophilus, and Lactobacillus delbrueckii subsp. lactis. Evidence for the presence of glutamine to pGlu cyclase activity in lactic acid bacteria was provided. Cell lysates obtained from cultures of L. helveticus, L. delbrueckii subsp. bulgaricus, L. delbrueckii subsp. lactis, and S. thermophilus showed the ability to cyclize glutamine to pGlu, resulting in processing yields from 1.4 to 30.3%, depending on the subspecies. Formation of pGlu from free glutamine appeared to be similar to that observed using a glutamine-glutamine dipeptide substrate. Under the experimental conditions applied, pGlu aminopeptidase activity was only detected in L. helveticus. Thus, pGlu formation in long-ripened cooked cheese may depend on the activity of thermophilic lactic acid bacteria.

  18. Microbial Production of Short Chain Fatty Acids from Lignocellulosic Biomass: Current Processes and Market.

    PubMed

    Baumann, Ivan; Westermann, Peter

    2016-01-01

    Biological production of organic acids from conversion of biomass derivatives has received increased attention among scientists and engineers and in business because of the attractive properties such as renewability, sustainability, degradability, and versatility. The aim of the present review is to summarize recent research and development of short chain fatty acids production by anaerobic fermentation of nonfood biomass and to evaluate the status and outlook for a sustainable industrial production of such biochemicals. Volatile fatty acids (VFAs) such as acetic acid, propionic acid, and butyric acid have many industrial applications and are currently of global economic interest. The focus is mainly on the utilization of pretreated lignocellulosic plant biomass as substrate (the carbohydrate route) and development of the bacteria and processes that lead to a high and economically feasible production of VFA. The current and developing market for VFA is analyzed focusing on production, prices, and forecasts along with a presentation of the biotechnology companies operating in the market for sustainable biochemicals. Finally, perspectives on taking sustainable product of biochemicals from promise to market introduction are reviewed.

  19. Microbial Production of Short Chain Fatty Acids from Lignocellulosic Biomass: Current Processes and Market

    PubMed Central

    Baumann, Ivan

    2016-01-01

    Biological production of organic acids from conversion of biomass derivatives has received increased attention among scientists and engineers and in business because of the attractive properties such as renewability, sustainability, degradability, and versatility. The aim of the present review is to summarize recent research and development of short chain fatty acids production by anaerobic fermentation of nonfood biomass and to evaluate the status and outlook for a sustainable industrial production of such biochemicals. Volatile fatty acids (VFAs) such as acetic acid, propionic acid, and butyric acid have many industrial applications and are currently of global economic interest. The focus is mainly on the utilization of pretreated lignocellulosic plant biomass as substrate (the carbohydrate route) and development of the bacteria and processes that lead to a high and economically feasible production of VFA. The current and developing market for VFA is analyzed focusing on production, prices, and forecasts along with a presentation of the biotechnology companies operating in the market for sustainable biochemicals. Finally, perspectives on taking sustainable product of biochemicals from promise to market introduction are reviewed. PMID:27556042

  20. Changes in Phenolic Acid Content in Maize during Food Product Processing.

    PubMed

    Butts-Wilmsmeyer, Carrie J; Mumm, Rita H; Rausch, Kent D; Kandhola, Gurshagan; Yana, Nicole A; Happ, Mary M; Ostezan, Alexandra; Wasmund, Matthew; Bohn, Martin O

    2018-04-04

    The notion that many nutrients and beneficial phytochemicals in maize are lost due to food product processing is common, but this has not been studied in detail for the phenolic acids. Information regarding changes in phenolic acid content throughout processing is highly valuable because some phenolic acids are chemopreventive agents of aging-related diseases. It is unknown when and why these changes in phenolic acid content might occur during processing, whether some maize genotypes might be more resistant to processing induced changes in phenolic acid content than other genotypes, or if processing affects the bioavailability of phenolic acids in maize-based food products. For this study, a laboratory-scale processing protocol was developed and used to process whole maize kernels into toasted cornflakes. High-throughput microscale wet-lab analyses were applied to determine the concentrations of soluble and insoluble-bound phenolic acids in samples of grain, three intermediate processing stages, and toasted cornflakes obtained from 12 ex-PVP maize inbreds and seven hybrids. In the grain, insoluble-bound ferulic acid was the most common phenolic acid, followed by insoluble-bound p-coumaric acid and soluble cinnamic acid, a precursor to the phenolic acids. Notably, the ferulic acid content was approximately 1950 μg/g, more than ten-times the concentration of many fruits and vegetables. Processing reduced the content of the phenolic acids regardless of the genotype. Most changes occurred during dry milling due to the removal of the bran. The concentration of bioavailable soluble ferulic and p-coumaric acid increased negligibly due to thermal stresses. Therefore, the current dry milling based processing techniques used to manufacture many maize-based foods, including breakfast cereals, are not conducive for increasing the content of bioavailable phenolics in processed maize food products. This suggests that while maize is an excellent source of phenolics, alternative

  1. Bio-based production of organic acids with Corynebacterium glutamicum

    PubMed Central

    Wieschalka, Stefan; Blombach, Bastian; Bott, Michael; Eikmanns, Bernhard J

    2013-01-01

    The shortage of oil resources, the steadily rising oil prices and the impact of its use on the environment evokes an increasing political, industrial and technical interest for development of safe and efficient processes for the production of chemicals from renewable biomass. Thus, microbial fermentation of renewable feedstocks found its way in white biotechnology, complementing more and more traditional crude oil-based chemical processes. Rational strain design of appropriate microorganisms has become possible due to steadily increasing knowledge on metabolism and pathway regulation of industrially relevant organisms and, aside from process engineering and optimization, has an outstanding impact on improving the performance of such hosts. Corynebacterium glutamicum is well known as workhorse for the industrial production of numerous amino acids. However, recent studies also explored the usefulness of this organism for the production of several organic acids and great efforts have been made for improvement of the performance. This review summarizes the current knowledge and recent achievements on metabolic engineering approaches to tailor C. glutamicum for the bio-based production of organic acids. We focus here on the fermentative production of pyruvate, l-and d-lactate, 2-ketoisovalerate, 2-ketoglutarate, and succinate. These organic acids represent a class of compounds with manifold application ranges, e.g. in pharmaceutical and cosmetics industry, as food additives, and economically very interesting, as precursors for a variety of bulk chemicals and commercially important polymers. Funding Information Work in the laboratories of the authors was supported by the Fachagentur Nachwachsende Rohstoffe (FNR) of the Bundesministerium für Ernährung, Landwirtschaft und Verbraucherschutz (BMELV; FNR Grants 220-095-08A and 220-095-08D; Bio-ProChemBB project, ERA-IB programme), by the Deutsche Bundesstiftung Umwelt (DBU Grant AZ13040/05) and the Evonik Degussa AG. PMID

  2. Determination of amino acids in grape-derived products: a review.

    PubMed

    Callejón, R M; Troncoso, A M; Morales, M L

    2010-06-15

    The amino acids present in foods and beverages affect the quality of these products and they play an important role in enology. Amino acids are consumed by yeasts as a source of nitrogen during alcoholic fermentation and are precursors of aroma compounds. In this review various chromatographic methodologies for the determination of amino acids are described, and specific applications for the analysis of amino acid content are discussed. Amino acids usually need to be derivatized to make them more detectable. Several derivatizing reagents have been employed for the determination of amino acids in enological applications, and each has its advantages and disadvantages.

  3. Mixed Carboxylic Acid Production by Megasphaera elsdenii from Glucose and Lignocellulosic Hydrolysate

    DOE PAGES

    Nelson, Robert S.; Peterson, Darren J.; Karp, Eric M.; ...

    2017-03-01

    Here, volatile fatty acids (VFAs) can be readily produced from many anaerobic microbes and subsequently utilized as precursors to renewable biofuels and biochemicals. Megasphaera elsdenii represents a promising host for production of VFAs, butyric acid (BA) and hexanoic acid (HA). However, due to the toxicity of these acids, product removal via an extractive fermentation system is required to achieve high titers and productivities. Here, we examine multiple aspects of extractive separations to produce BA and HA from glucose and lignocellulosic hydrolysate with M. elsdenii. A mixture of oleyl alcohol and 10% (v/v) trioctylamine was selected as an extraction solvent duemore » to its insignificant inhibitory effect on the bacteria. Batch extractive fermentations were conducted in the pH range of 5.0 to 6.5 to select the best cell growth rate and extraction efficiency combination. Subsequently, fed-batch pertractive fermentations were run over 230 h, demonstrating high BA and HA concentrations in the extracted fraction (57.2 g/L from ~190 g/L glucose) and productivity (0.26 g/L/h). To our knowledge, these are the highest combined acid titers and productivity values reported for M. elsdenii and bacterial mono-cultures from sugars. Lastly, the production of BA and HA (up to 17 g/L) from lignocellulosic sugars was demonstrated.« less

  4. Mixed Carboxylic Acid Production by Megasphaera elsdenii from Glucose and Lignocellulosic Hydrolysate

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

    Nelson, Robert S.; Peterson, Darren J.; Karp, Eric M.

    Here, volatile fatty acids (VFAs) can be readily produced from many anaerobic microbes and subsequently utilized as precursors to renewable biofuels and biochemicals. Megasphaera elsdenii represents a promising host for production of VFAs, butyric acid (BA) and hexanoic acid (HA). However, due to the toxicity of these acids, product removal via an extractive fermentation system is required to achieve high titers and productivities. Here, we examine multiple aspects of extractive separations to produce BA and HA from glucose and lignocellulosic hydrolysate with M. elsdenii. A mixture of oleyl alcohol and 10% (v/v) trioctylamine was selected as an extraction solvent duemore » to its insignificant inhibitory effect on the bacteria. Batch extractive fermentations were conducted in the pH range of 5.0 to 6.5 to select the best cell growth rate and extraction efficiency combination. Subsequently, fed-batch pertractive fermentations were run over 230 h, demonstrating high BA and HA concentrations in the extracted fraction (57.2 g/L from ~190 g/L glucose) and productivity (0.26 g/L/h). To our knowledge, these are the highest combined acid titers and productivity values reported for M. elsdenii and bacterial mono-cultures from sugars. Lastly, the production of BA and HA (up to 17 g/L) from lignocellulosic sugars was demonstrated.« less

  5. Biotechnological production of caffeic acid derivatives from cell and organ cultures of Echinacea species.

    PubMed

    Murthy, Hosakatte Niranjana; Kim, Yun-Soo; Park, So-Young; Paek, Kee-Yoeup

    2014-09-01

    Caffeic acid derivatives (CADs) are a group of bioactive compounds which are produced in Echinacea species especially Echinacea purpurea, Echinacea angustifolia, and Echinacea pallida. Echinacea is a popular herbal medicine used in the treatment of common cold and it is also a prominent dietary supplement used throughout the world. Caffeic acid, chlorogenic acid (5-O-caffeoylquinic acid), caftaric acid (2-O-caffeoyltartaric acid), cichoric acid (2, 3-O-dicaffeoyltartaric acid), cynarin, and echinacoside are some of the important CADs which have varied pharmacological activities. The concentrations of these bioactive compounds are species specific and also they vary considerably with the cultivated Echinacea species due to geographical location, stage of development, time of harvest, and growth conditions. Due to these reasons, plant cell and organ cultures have become attractive alternative for the production of biomass and caffeic acid derivatives. Adventitious and hairy roots have been induced in E. pupurea and E. angustifolia, and suspension cultures have been established from flask to bioreactor scale for the production of biomass and CADs. Tremendous progress has been made in this area; various bioprocess methods and strategies have been developed for constant high-quality productivity of biomass and secondary products. This review is aimed to discuss biotechnological methods and approaches employed for the sustainable production of CADs.

  6. Progress of succinic acid production from renewable resources: Metabolic and fermentative strategies.

    PubMed

    Jiang, Min; Ma, Jiangfeng; Wu, Mingke; Liu, Rongming; Liang, Liya; Xin, Fengxue; Zhang, Wenming; Jia, Honghua; Dong, Weiliang

    2017-12-01

    Succinic acid is a four-carbon dicarboxylic acid, which has attracted much interest due to its abroad usage as a precursor of many industrially important chemicals in the food, chemicals, and pharmaceutical industries. Facing the shortage of crude oil supply and demand of sustainable development, biological production of succinic acid from renewable resources has become a topic of worldwide interest. In recent decades, robust producing strain selection, metabolic engineering of model strains, and process optimization for succinic acid production have been developed. This review provides an overview of succinic acid producers and cultivation technology, highlight some of the successful metabolic engineering approaches. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. Production of butyric acid from acid hydrolysate of corn husk in fermentation by Clostridium tyrobutyricum: kinetics and process economic analysis.

    PubMed

    Xiao, Zhiping; Cheng, Chu; Bao, Teng; Liu, Lujie; Wang, Bin; Tao, Wenjing; Pei, Xun; Yang, Shang-Tian; Wang, Minqi

    2018-01-01

    Butyric acid is an important chemical currently produced from petrochemical feedstocks. Its production from renewable, low-cost biomass in fermentation has attracted large attention in recent years. In this study, the feasibility of corn husk, an abundant agricultural residue, for butyric acid production by using Clostridium tyrobutyricum immobilized in a fibrous bed bioreactor (FBB) was evaluated. Hydrolysis of corn husk (10% solid loading) with 0.4 M H 2 SO 4 at 110 °C for 6 h resulted in a hydrolysate containing ~ 50 g/L total reducing sugars (glucose:xylose = 1.3:1.0). The hydrolysate was used for butyric acid fermentation by C. tyrobutyricum in a FBB, which gave 42.6 and 53.0% higher butyric acid production from glucose and xylose, respectively, compared to free-cell fermentations. Fermentation with glucose and xylose mixture (1:1) produced 50.37 ± 0.04 g L -1 butyric acid with a yield of 0.38 ± 0.02 g g -1 and productivity of 0.34 ± 0.03 g L -1  h -1 . Batch fermentation with corn husk hydrolysate produced 21.80 g L -1 butyric acid with a yield of 0.39 g g -1 , comparable to those from glucose. Repeated-batch fermentations consistently produced 20.75 ± 0.65 g L -1 butyric acid with an average yield of 0.39 ± 0.02 g g -1 in three consecutive batches. An extractive fermentation process can be used to produce, separate, and concentrate butyric acid to > 30% (w/v) sodium butyrate at an economically attractive cost for application as an animal feed supplement. A high concentration of total reducing sugars at ~ 50% (w/w) yield was obtained from corn husk after acid hydrolysis. Stable butyric acid production from corn husk hydrolysate was achieved in repeated-batch fermentation with C. tyrobutyricum immobilized in a FBB, demonstrating that corn husk can be used as an economical substrate for butyric acid production.

  8. Enhanced pinocembrin production in Escherichia coli by regulating cinnamic acid metabolism

    PubMed Central

    Cao, Weijia; Ma, Weichao; Wang, Xin; Zhang, Bowen; Cao, Xun; Chen, Kequan; Li, Yan; Ouyang, Pingkai

    2016-01-01

    Microbial biosynthesis of pinocembrin is of great interest in the area of drug research and human healthcare. Here we found that the accumulation of the pathway intermediate cinnamic acid adversely affected pinocembrin production. Hence, a stepwise metabolic engineering strategy was carried out aimed at eliminating this pathway bottleneck and increasing pinocembrin production. The screening of gene source and the optimization of gene expression was first employed to regulate the synthetic pathway of cinnamic acid, which showed a 3.53-fold increase in pinocembrin production (7.76 mg/L) occurred with the alleviation of cinnamic acid accumulation in the engineered E. coli. Then, the downstream pathway that consuming cinnamic acid was optimized by the site-directed mutagenesis of chalcone synthase and cofactor engineering. S165M mutant of chalcone synthase could efficiently improve the pinocembrin production, and allowed the product titer of pinocembrin increased to 40.05 mg/L coupled with the malonyl-CoA engineering. With a two-phase pH fermentation strategy, the cultivation of the optimized strain resulted in a final pinocembrin titer of 67.81 mg/L. The results and engineering strategies demonstrated here would hold promise for the titer improvement of other flavonoids. PMID:27586788

  9. Enhanced pinocembrin production in Escherichia coli by regulating cinnamic acid metabolism.

    PubMed

    Cao, Weijia; Ma, Weichao; Wang, Xin; Zhang, Bowen; Cao, Xun; Chen, Kequan; Li, Yan; Ouyang, Pingkai

    2016-09-02

    Microbial biosynthesis of pinocembrin is of great interest in the area of drug research and human healthcare. Here we found that the accumulation of the pathway intermediate cinnamic acid adversely affected pinocembrin production. Hence, a stepwise metabolic engineering strategy was carried out aimed at eliminating this pathway bottleneck and increasing pinocembrin production. The screening of gene source and the optimization of gene expression was first employed to regulate the synthetic pathway of cinnamic acid, which showed a 3.53-fold increase in pinocembrin production (7.76 mg/L) occurred with the alleviation of cinnamic acid accumulation in the engineered E. coli. Then, the downstream pathway that consuming cinnamic acid was optimized by the site-directed mutagenesis of chalcone synthase and cofactor engineering. S165M mutant of chalcone synthase could efficiently improve the pinocembrin production, and allowed the product titer of pinocembrin increased to 40.05 mg/L coupled with the malonyl-CoA engineering. With a two-phase pH fermentation strategy, the cultivation of the optimized strain resulted in a final pinocembrin titer of 67.81 mg/L. The results and engineering strategies demonstrated here would hold promise for the titer improvement of other flavonoids.

  10. Antibacterial free fatty acids: activities, mechanisms of action and biotechnological potential.

    PubMed

    Desbois, Andrew P; Smith, Valerie J

    2010-02-01

    Amongst the diverse and potent biological activities of free fatty acids (FFAs) is the ability to kill or inhibit the growth of bacteria. The antibacterial properties of FFAs are used by many organisms to defend against parasitic or pathogenic bacteria. Whilst their antibacterial mode of action is still poorly understood, the prime target of FFA action is the cell membrane, where FFAs disrupt the electron transport chain and oxidative phosphorylation. Besides interfering with cellular energy production, FFA action may also result from the inhibition of enzyme activity, impairment of nutrient uptake, generation of peroxidation and auto-oxidation degradation products or direct lysis of bacterial cells. Their broad spectrum of activity, non-specific mode of action and safety makes them attractive as antibacterial agents for various applications in medicine, agriculture and food preservation, especially where the use of conventional antibiotics is undesirable or prohibited. Moreover, the evolution of inducible FFA-resistant phenotypes is less problematic than with conventional antibiotics. The potential for commercial or biomedical exploitation of antibacterial FFAs, especially for those from natural sources, is discussed.

  11. Inhibitory effects of indole α-lipoic acid derivatives on nitric oxide production in LPS/IFNγ activated RAW 264.7 macrophages.

    PubMed

    Karabay, Arzu Zeynep; Koc, Aslı; Gurkan-Alp, A Selen; Buyukbingol, Zeliha; Buyukbingol, Erdem

    2015-04-01

    Alpha-lipoic acid (α-lipoic acid) is a potent antioxidant compound that has been shown to possess anti-inflammatory effects. RAW 264.7 macrophages produce various inflammatory mediators such as nitric oxide, IL-1β, IL-6 and TNF-alpha upon activation with LPS (Lipopolysaccharide) and IFNγ (interferon gamma). In this study, the effect of 12 synthetic indole α-lipoic acid derivatives on nitric oxide production and iNOS (inducible nitric oxide synthase) protein expression in LPS/IFNγ activated RAW 264.7 macrophages was determined. Cell proliferation, nitric oxide levels and iNOS protein expression were examined with thiazolyl blue tetrazolium blue test, griess assay and western blot, respectively. Our results showed that all of the indole α-lipoic acid derivatives showed significant inhibitory effects on nitric oxide production and iNOS protein levels (p < 0.05). The most active compounds were identified as compound I-4b, I-4e and II-3b. In conclusion, these indole α-lipoic acid derivatives may have the potential for treatment of inflammatory conditions related with high nitric oxide production. Copyright © 2015 John Wiley & Sons, Ltd.

  12. Elicitation of gymnemic acid production in cell suspension cultures of Gymnema sylvestre R.Br. through endophytic fungi.

    PubMed

    Netala, Vasudeva Reddy; Kotakadi, Venkata Subbaiah; Gaddam, Susmila Aparna; Ghosh, Sukhendu Bikash; Tartte, Vijaya

    2016-12-01

    The enhancement of plant secondary metabolite production in cell suspension cultures through biotic or abiotic elicitation has become a potential biotechnological approach for commercialization or large-scale production of bioactive compounds. Gymnema sylvestre R.Br. is an important medicinal plant, rich in a group of oleanane triterpenoid saponins called gymnemic acid, well known for its anti-diabetic activity. Two endophytic fungal strains were isolated from the leaves of G. sylvestre and identified as Polyancora globosa and Xylaria sp. based on the PCR amplification and internal transcribed spacer (ITS 1-5.8S-ITS 2) sequencing of 18S rRNA gene. The process of elicitation of cell suspension cultures of G. sylvestre with dried powder of fungal mycelia (DPFM) and extracellular culture filtrate (ECF) of endophytic fungi consistently enhanced the accumulation of gymnemic acid and the DPFM was proved to be an effective elicitor when compared to the ECF. The DPFM elicited the gymnemic acid content in the range of 2.57-10.45-fold, while the ECF elicited the gymnemic acid content in the range of 2.39-7.8-fold. P. globosa, a novel and a rare endophytic fungal strain, has shown a great influence on the production of gymnemic acid. Cell suspension cultures elicited with DPFM of P. globosa produced higher amount of gymnemic acid content (124.23 mg/g dried cell weight) compared to the cultures elicited with DPFM of Xylaria sp. (102.24 mg/g DCW). But the cultures treated with consortium of DPFM of both fungi showed great influence on the production of gymnemic acid (139.98 mg/g DCW) than the cultures treated with DPFM alone. Similarly, cultures treated with consortium of ECF of both fungi produced more gymnemic acid content (94.86 mg/g DCW) compared with cultures treated with ECF of Xylaria sp. (77.93 mg/g DCW) and ECF of P. globosa (78.65 mg/g DCW) alone.

  13. Continuous succinic acid production from xylose by Actinobacillus succinogenes.

    PubMed

    Bradfield, Michael F A; Nicol, Willie

    2016-02-01

    Continuous, anaerobic fermentations of D-xylose were performed by Actinobacillus succinogenes 130Z in a custom, biofilm reactor at dilution rates of 0.05, 0.10 and 0.30 h(-1). Succinic acid yields on xylose (0.55-0.68 g g(-1)), titres (10.9-29.4 g L(-1)) and productivities (1.5-3.4 g L(-1) h(-1)) were lower than those of a previous study on glucose, but product ratios (succinic acid/acetic acid = 3.0-5.0 g g(-1)) and carbohydrate consumption rates were similar. Also, mass balance closures on xylose were up to 18.2 % lower than those on glucose. A modified HPLC method revealed pyruvic acid excretion at appreciable concentrations (1.2-1.9 g L(-1)) which improved the mass balance closure by up to 16.8 %. Furthermore, redox balances based on the accounted xylose consumed and the excreted metabolites, indicated an overproduction of reducing power. The oxidative pentose phosphate pathway was shown to be a plausible source of the additional reducing power.

  14. Bacillus sphaericus: the highest bacterial tannase producer with potential for gallic acid synthesis.

    PubMed

    Raghuwanshi, Shailendra; Dutt, Kakoli; Gupta, Pritesh; Misra, Swati; Saxena, Rajendra Kumar

    2011-06-01

    An indigenously isolated strain of Bacillus sphaericus was found to produce 1.21 IU/ml of tannase under unoptimized conditions. Optimizing the process one variable at a time resulted in the production of 7.6 IU/ml of tannase in 48 h in the presence of 1.5% tannic acid. A 9.26-fold increase in tannase production was achieved upon further optimization using response surface methodology (RSM), a statistical approach. This increase led to a production level of 11.2I U/ml in medium containing 2.0% tannic acid, 2.5% galactose, 0.25% ammonium chloride, and 0.1% MgSO(4) pH 6.0 incubated at 37°C and 100 rpm for 48 h with a 2.0% inoculum level. Scaling up tannase production in a 30-l bioreactor resulted in the production of 16.54 IU/ml after 36 h. Thus far, this tannase production is the highest reported in this bacterial strain. Partially purified tannase exhibited an optimum pH of 5.0 with activity in the pH range of 3 to 8; 50°C was the optimal temperature for activity. Efficient conversion of tannic acid to purified gallic acid (90.80%) was achieved through crystallization. Copyright © 2011 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  15. 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 %.

  16. Dominant lactic acid bacteria and their technological properties isolated from the Himalayan ethnic fermented milk products.

    PubMed

    Dewan, Sailendra; Tamang, Jyoti Prakash

    2007-10-01

    Ethnic people of the Himalayan regions of India, Nepal, Bhutan and China consume a variety of indigenous fermented milk products made from cows milk as well as yaks milk. These lesser-known ethnic fermented foods are dahi, mohi, chhurpi, somar, philu and shyow. The population of lactic acid bacteria (LAB) ranged from 10(7) to 10(8) cfu/g in these Himalayan milk products. A total of 128 isolates of LAB were isolated from 58 samples of ethnic fermented milk products collected from different places of India, Nepal and Bhutan. Based on phenotypic characterization including API sugar test, the dominant lactic acid bacteria were identified as Lactobacillus bifermentans, Lactobacillus paracasei subsp. pseudoplantarum, Lactobacillus kefir, Lactobacillus hilgardii, Lactobacillus alimentarius, Lactobacillus paracasei subsp. paracasei, Lactobacillus plantarum, Lactococcus lactis subsp. lactis, Lactococcus lactis subsp. cremoris and Enterococcus faecium. LAB produced a wide spectrum of enzymes and showed high galactosidase, leucine-arylamidase and phosphatase activities. They showed antagonistic properties against selected Gram-negative bacteria. None of the strains produced bacteriocin and biogenic amines under the test conditions used. Most strains of LAB coagulated skim milk with a moderate drop in pH. Some strains of LAB showed a high degree of hydrophobicity, suggesting these strains may have useful adhesive potential. This paper is the first report on functional lactic acid bacterial composition in some lesser-known ethnic fermented milk products of the Himalayas.

  17. Vanillic acid from Actinidia deliciosa impedes virulence in Serratia marcescens by affecting S-layer, flagellin and fatty acid biosynthesis proteins.

    PubMed

    Sethupathy, Sivasamy; Ananthi, Sivagnanam; Selvaraj, Anthonymuthu; Shanmuganathan, Balakrishnan; Vigneshwari, Loganathan; Balamurugan, Krishnaswamy; Mahalingam, Sundarasamy; Pandian, Shunmugiah Karutha

    2017-11-27

    Serratia marcescens is one of the important nosocomial pathogens which rely on quorum sensing (QS) to regulate the production of biofilm and several virulence factors. Hence, blocking of QS has become a promising approach to quench the virulence of S. marcescens. For the first time, QS inhibitory (QSI) and antibiofilm potential of Actinidia deliciosa have been explored against S. marcescens clinical isolate (CI). A. deliciosa pulp extract significantly inhibited the virulence and biofilm production without any deleterious effect on the growth. Vanillic acid was identified as an active lead responsible for the QSI activity. Addition of vanillic acid to the growth medium significantly affected the QS regulated production of biofilm and virulence factors in a concentration dependent mode in S. marcescens CI, ATCC 14756 and MG1. Furthermore vanillic acid increased the survival of Caenorhabditis elegans upon S. marcescens infection. Proteomic analysis and mass spectrometric identification of differentially expressed proteins revealed the ability of vanillic acid to modulate the expression of proteins involved in S-layers, histidine, flagellin and fatty acid production. QSI potential of the vanillic acid observed in the current study paves the way for exploring it as a potential therapeutic candidate to treat S. marcescens infections.

  18. Monascus ruber as cell factory for lactic acid production at low pH.

    PubMed

    Weusthuis, Ruud A; Mars, Astrid E; Springer, Jan; Wolbert, Emil Jh; van der Wal, Hetty; de Vrije, Truus G; Levisson, Mark; Leprince, Audrey; Houweling-Tan, G Bwee; Pha Moers, Antoine; Hendriks, Sjon Na; Mendes, Odette; Griekspoor, Yvonne; Werten, Marc Wt; Schaap, Peter J; van der Oost, John; Eggink, Gerrit

    2017-07-01

    A Monascus ruber strain was isolated that was able to grow on mineral medium at high sugar concentrations and 175g/l lactic acid at pH 2.8. Its genome and transcriptomes were sequenced and annotated. Genes encoding lactate dehydrogenase (LDH) were introduced to accomplish lactic acid production and two genes encoding pyruvate decarboxylase (PDC) were knocked out to subdue ethanol formation. The strain preferred lactic acid to glucose as carbon source, which hampered glucose consumption and therefore also lactic acid production. Lactic acid consumption was stopped by knocking out 4 cytochrome-dependent LDH (CLDH) genes, and evolutionary engineering was used to increase the glucose consumption rate. Application of this strain in a fed-batch fermentation resulted in a maximum lactic acid titer of 190g/l at pH 3.8 and 129g/l at pH 2.8, respectively 1.7 and 2.2 times higher than reported in literature before. Yield and productivity were on par with the best strains described in literature for lactic acid production at low pH. Copyright © 2017 International Metabolic Engineering Society. Published by Elsevier Inc. All rights reserved.

  19. Inhibition of Fusarium Growth and Mycotoxin Production in Culture Medium and in Maize Kernels by Natural Phenolic Acids.

    PubMed

    Ferruz, Elena; Loran, Susana; Herrera, Marta; Gimenez, Isabel; Bervis, Noemi; Barcena, Carmen; Carramiñana, Juan Jose; Juan, Teresa; Herrera, Antonio; Ariño, Agustin

    2016-10-01

    The possible role of natural phenolic compounds in inhibiting fungal growth and toxin production has been of recent interest as an alternative strategy to the use of chemical fungicides for the maintenance of food safety. Fusarium is a worldwide fungal genus mainly associated with cereal crops. The most important Fusarium mycotoxins are trichothecenes, zearalenone, and fumonisins. This study was conducted to evaluate the potential of four natural phenolic acids (caffeic, ferulic, p-coumaric, and chlorogenic) for the control of mycelial growth and mycotoxin production by six toxigenic species of Fusarium . The addition of phenolic acids to corn meal agar had a marked inhibitory effect on the radial growth of all Fusarium species at levels of 2.5 to 10 mM in a dose-response pattern, causing total inhibition (100%) in all species except F. sporotrichioides and F. langsethiae . However, the effects of phenolic acids on mycotoxin production in maize kernels were less evident than the effects on growth. The fungal species differed in their responses to the phenolic acid treatments, and significant reductions in toxin concentrations were observed only for T-2 and HT-2 (90% reduction) and zearalenone (48 to 77% reduction). These results provide data that could be used for developing pre- and postharvest strategies for controlling Fusarium infection and subsequent toxin production in cereal grains.

  20. Production of D-lactic acid by Corynebacterium glutamicum under oxygen deprivation.

    PubMed

    Okino, Shohei; Suda, Masako; Fujikura, Keitaro; Inui, Masayuki; Yukawa, Hideaki

    2008-03-01

    In mineral salts medium under oxygen deprivation, Corynebacterium glutamicum exhibits high productivity of L-lactic acid accompanied with succinic and acetic acids. In taking advantage of this elevated productivity, C. glutamicum was genetically modified to produce D-lactic acid. The modification involved expression of fermentative D-lactate dehydrogenase (D-LDH)-encoding genes from Escherichia coli and Lactobacillus delbrueckii in L-lactate dehydrogenase (L-LDH)-encoding ldhA-null C. glutamicum mutants to yield strains C. glutamicum DeltaldhA/pCRB201 and C. glutamicum DeltaldhA/pCRB204, respectively. The productivity of C. glutamicum DeltaldhA/pCRB204 was fivefold higher than that of C. glutamicum DeltaldhA/pCRB201. By using C. glutamicum DeltaldhA/pCRB204 cells packed to a high density in mineral salts medium, up to 1,336 mM (120 g l(-1)) of D-lactic acid of greater than 99.9% optical purity was produced within 30 h.

  1. Brewery Waste Reuse for Protease Production by Lactic 
Acid Fermentation

    PubMed Central

    2017-01-01

    Summary This study evaluated the use of three solid brewery wastes: brewer’s spent grain, hot trub and residual brewer’s yeast, as alternative media for the cultivation of lactic acid bacteria to evaluate their potential for proteolytic enzyme production. Initially, a mixture experimental design was used to evaluate the effect of each residue, as well as different mixtures (with the protein content set at 4%) in the enzyme production. At predetermined intervals, the solid and liquid fractions were separated and the extracellular proteolytic activity was determined. After selecting the best experimental conditions, a second experiment, factorial experimental design, was developed in order to evaluate the protein content in the media (1 to 7%) and the addition of fermentable sugar (glucose, 1 to 7%). Among the wastes, residual yeast showed the highest potential for the production of extracellular enzymes, generating a proteolytic extract with 2.6 U/mL in 3 h. However, due to the low content of the fermentable sugars in the medium, the addition of glucose also had a positive effect, increasing the proteolytic activity to 4.9 U/mL. The best experimental conditions of each experimental design were reproduced for comparison, and the enzyme content was separated by ethanol precipitation. The best medium produced a precipitated protein with proteolytic activity of 145.5 U/g. PMID:28867951

  2. Aqueous chlorination of mefenamic acid: kinetics, transformation by-products and ecotoxicity assessment.

    PubMed

    Adira Wan Khalit, Wan Nor; Tay, Kheng Soo

    2016-05-18

    Mefenamic acid (Mfe) is one of the most frequently detected nonsteroidal anti-inflammatory drugs in the environment. This study investigated the kinetics and the transformation by-products of Mfe during aqueous chlorination. The potential ecotoxicity of the transformation by-products was also evaluated. In the kinetic study, the second-order rate constant (kapp) for the reaction between Mfe and free available chlorine (FAC) was determined at 25 ± 0.1 °C. The result indicated that the degradation of Mfe by FAC is highly pH-dependent. When the pH was increased from 6 to 8, it was found that the kapp for the reaction between Mfe and FAC was decreased from 16.44 to 4.4 M(-1) s(-1). Characterization of the transformation by-products formed during the chlorination of Mfe was carried out using liquid chromatography-quadrupole time-of-flight accurate mass spectrometry. Four major transformation by-products were identified. These transformation by-products were mainly formed through hydroxylation, chlorination and oxidation reactions. Ecotoxicity assessment revealed that transformation by-products, particularly monohydroxylated Mfe which is more toxic than Mfe, can be formed during aqueous chlorination.

  3. Analysis of the production process of optically pure D-lactic acid from raw glycerol using engineered Escherichia coli strains.

    PubMed

    Posada, John A; Cardona, Carlos A; Gonzalez, Ramon

    2012-02-01

    Glycerol has become an ideal feedstock for producing fuels and chemicals. Here, five technological schemes for optically pure D: -lactic acid production from raw glycerol were designed, simulated, and economically assessed based on five fermentative scenarios using engineered Escherichia coli strains. Fermentative scenarios considered different qualities of glycerol (pure, 98 wt.%, and crude, 85 wt.%) with concentrations ranging from 20 to 60 g/l in the fermentation media, and two fermentation stages were also analyzed. Raw glycerol (60 wt.%) was considered as the feedstock feeding the production process in all cases; then a purification process of raw glycerol up to the required quality was required. Simulation processes were carried out using Aspen Plus, while economic assessments were performed using Aspen Icarus Process Evaluator. D: -Lactic acid recovery and purification processes were based on reactive extraction with tri-n-octylamine using dichloromethane as active extractant agent. The use of raw glycerol represents only between 2.4% and 7.8% of the total production costs. Also, the total production costs obtained of D: -lactic acid in all cases were lower than its sale price indicating that these processes are potentially profitable. Thus, the best configuration process requires the use of crude glycerol diluted at 40 g/l with total glycerol consumption and with D: -lactic acid recovering by reactive extraction. The lowest obtained total production cost was 1.015 US$/kg with a sale price/production cost ratio of 1.53.

  4. Enhanced solid-state citric acid bio-production using apple pomace waste through surface response methodology.

    PubMed

    Dhillon, G S; Brar, S K; Verma, M; Tyagi, R D

    2011-04-01

      To evaluate the potential of apple pomace (AP) supplemented with rice husk for hyper citric acid production through solid-state fermentation by Aspergillus niger NRRL-567. Optimization of two key parameters, such as moisture content and inducer (ethanol and methanol) concentration was carried out by response surface methodology.   In this study, the effect of two crucial process parameters for solid-state citric acid fermentation by A. niger using AP waste supplemented with rice husk were thoroughly investigated in Erlenmeyer flasks through response surface methodology. Moisture and methanol had significant positive effect on citric acid production by A. niger grown on AP (P < 0·05). Higher values of citric acid on AP by A. niger (342·41gkg(-1) and 248·42gkg(-1) dry substrate) were obtained with 75% (v/w) moisture along with two inducers [3% (v/w) methanol and 3% (v/w) ethanol] with fermentation efficiency of 93·90% and 66·42%, respectively depending upon the total carbon utilized after 144h of incubation period. With the same optimized parameters, conventional tray fermentation was conducted. The citric acid concentration of 187·96gkg(-1) dry substrate with 3% (v/w) ethanol and 303·34gkg(-1) dry substrate with 3% (v/w) methanol were achieved representing fermentation efficiency of 50·80% and 82·89% in tray fermentation depending upon carbon utilization after 120h of incubation period.   Apple pomace proved to be the promising substrate for the hyper production of citric acid through solid-state tray fermentation, which is an economical technique and does not require any sophisticated instrumentation.   The study established that the utilization of agro-industrial wastes have positive repercussions on the economy and will help to meet the increasing demands of citric acid and moreover will help to alleviate the environmental problems resulting from the disposal of agro-industrial wastes. © 2011 The Authors. Journal of Applied Microbiology

  5. Statistical potential-based amino acid similarity matrices for aligning distantly related protein sequences.

    PubMed

    Tan, Yen Hock; Huang, He; Kihara, Daisuke

    2006-08-15

    Aligning distantly related protein sequences is a long-standing problem in bioinformatics, and a key for successful protein structure prediction. Its importance is increasing recently in the context of structural genomics projects because more and more experimentally solved structures are available as templates for protein structure modeling. Toward this end, recent structure prediction methods employ profile-profile alignments, and various ways of aligning two profiles have been developed. More fundamentally, a better amino acid similarity matrix can improve a profile itself; thereby resulting in more accurate profile-profile alignments. Here we have developed novel amino acid similarity matrices from knowledge-based amino acid contact potentials. Contact potentials are used because the contact propensity to the other amino acids would be one of the most conserved features of each position of a protein structure. The derived amino acid similarity matrices are tested on benchmark alignments at three different levels, namely, the family, the superfamily, and the fold level. Compared to BLOSUM45 and the other existing matrices, the contact potential-based matrices perform comparably in the family level alignments, but clearly outperform in the fold level alignments. The contact potential-based matrices perform even better when suboptimal alignments are considered. Comparing the matrices themselves with each other revealed that the contact potential-based matrices are very different from BLOSUM45 and the other matrices, indicating that they are located in a different basin in the amino acid similarity matrix space.

  6. In silico and in vitro studies of the reduction of unsaturated α,β bonds of trans-2-hexenedioic acid and 6-amino-trans-2-hexenoic acid – Important steps towards biobased production of adipic acid

    PubMed Central

    Westman, Gunnar; Eriksson, Leif A.; Mapelli, Valeria

    2018-01-01

    The biobased production of adipic acid, a precursor in the production of nylon, is of great interest in order to replace the current petrochemical production route. Glucose-rich lignocellulosic raw materials have high potential to replace the petrochemical raw material. A number of metabolic pathways have been proposed for the microbial conversion of glucose to adipic acid, but achieved yields and titers remain to be improved before industrial applications are feasible. One proposed pathway starts with lysine, an essential metabolite industrially produced from glucose by microorganisms. However, the drawback of this pathway is that several reactions are involved where there is no known efficient enzyme. By changing the order of the enzymatic reactions, we were able to identify an alternative pathway with one unknown enzyme less compared to the original pathway. One of the reactions lacking known enzymes is the reduction of the unsaturated α,β bond of 6-amino-trans-2-hexenoic acid and trans-2-hexenedioic acid. To identify the necessary enzymes, we selected N-ethylmaleimide reductase from Escherichia coli and Old Yellow Enzyme 1 from Saccharomyces pastorianus. Despite successful in silico docking studies, where both target substrates could fit in the enzyme pockets, and hydrogen bonds with catalytic residues of both enzymes were predicted, no in vitro activity was observed. We hypothesize that the lack of activity is due to a difference in electron withdrawing potential between the naturally reduced aldehyde and the carboxylate groups of our target substrates. Suggestions for protein engineering to induce the reactions are discussed, as well as the advantages and disadvantages of the two metabolic pathways from lysine. We have highlighted bottlenecks associated with the lysine pathways, and proposed ways of addressing them. PMID:29474495

  7. Efficient Production of Lactic Acid from Sweet Sorghum Juice by a Newly Isolated Lactobacillus salivarius CGMCC 7.75.

    PubMed

    Liu, Quanlan; Wang, Shanglong; Zhi, Jian-Fei; Ming, Henglei; Teng, Dawei

    2013-09-01

    Sweet sorghum juice was a cheap and renewable resource, and also a potential carbon source for the fermentation production of lactic acid (LA) by a lactic acid bacterium. One newly isolated strain Lactobacillus salivarius CGMCC 7.75 showed the ability to produce the highest yield and optical purity of LA from sweet sorghum juice. Studies of feeding different concentrations of sweet sorghum juice and nitrogen source suggested the optimal concentrations of fermentation were 325 ml l(-1) and 20 g l(-1), respectively. This combination produced 142.49 g l(-1) LA with a productivity level of 0.90 g of LA per gram of sugars consumed. The results indicated the high LA concentration achieved using L. salivarius CGMCC 7.75 not only gives cheap industrial product, but also broaden the application of sweet sorghum.

  8. LED power efficiency of biomass, fatty acid, and carotenoid production in Nannochloropsis microalgae.

    PubMed

    Ma, Ruijuan; Thomas-Hall, Skye R; Chua, Elvis T; Eltanahy, Eladl; Netzel, Michael E; Netzel, Gabriele; Lu, Yinghua; Schenk, Peer M

    2018-03-01

    The microalga Nannochloropsis produces high-value omega-3-rich fatty acids and carotenoids. In this study the effects of light intensity and wavelength on biomass, fatty acid, and carotenoid production with respect to light output efficiency were investigated. Similar biomass and fatty acid yields were obtained at high light intensity (150 μmol m -2  s -1 ) LEDs on day 7 and low light intensity (50 μmol m -2  s -1 ) LEDs on day 11 during cultivation, but the power efficiencies of biomass and fatty acid (specifically eicosapentaenoic acid) production were higher for low light intensity. Interestingly, low light intensity enhanced both, carotenoid power efficiency of carotenoid biosynthesis and yield. White LEDs were neither advantageous for biomass and fatty acid yields, nor the power efficiency of biomass, fatty acid, and carotenoid production. Noticeably, red LED resulted in the highest biomass and fatty acid power efficiency, suggesting that LEDs can be fine-tuned to grow Nannochloropsis algae more energy-efficiently. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. Induction of Thymic Stromal Lymphopoietin Production by Nonanoic Acid and Exacerbation of Allergic Inflammation in Mice

    PubMed Central

    Yamashita, Saori; Segawa, Ryosuke; Satou, Nozomi; Hiratsuka, Masahiro; Leonard, Warren J.; Hirasawa, Noriyasu

    2013-01-01

    Background Thymic stromal lymphopoietin (TSLP) plays critical roles in the induction and exacerbation of allergic diseases. We tested various chemicals in the environment and found that xylene and 1,2,4-trimethylbenzene induced the production of TSLP in vivo. These findings prompted us to search for additional chemicals that induce TSLP production. In this study, we examined whether fatty acids could induce the production of TSLP in vivo and exacerbate allergic inflammation. Methods Various fatty acids and related compounds were painted on the ear lobes of mice and the amount of TSLP in the homogenate of ear lobe tissue was determined. The effects of nonanoic acid on allergic inflammation were also examined. Results Octanoic acid, nonanoic acid, and decanoic acid markedly induced TSLP production, while a medium-chain aldehyde and alcohol showed only weak activity. Nonanoic acid induced the production of TSLP with a maximum at 24 h. TSLP production was even observed in nonanoic acid-treated C3H/HeJ mice that lacked functional toll-like receptor 4. The aryl hydrocarbon receptor agonist β-naphthoflavone did not induce TSLP production. Nonanoic acid promoted sensitization to ovalbumin, resulting in an enhancement in the cutaneous anaphylactic response. In addition, painting of nonanoic acid after the sensitization augmented picryl chloride-induced thickening of the ear, which was reversed in TSLP receptor-deficient mice. Conclusion Nonanoic acid and certain fatty acids induced TSLP production, resulting in the exacerbation of allergic inflammation. We propose that TSLP-inducing chemical compounds such as nonanoic acid be recognized as chemical allergo-accelerators. PMID:24060765

  10. Amino acid production exceeds plant nitrogen demand in Siberian tundra

    NASA Astrophysics Data System (ADS)

    Wild, Birgit; Eloy Alves, Ricardo J.; Bárta, Jiři; Čapek, Petr; Gentsch, Norman; Guggenberger, Georg; Hugelius, Gustaf; Knoltsch, Anna; Kuhry, Peter; Lashchinskiy, Nikolay; Mikutta, Robert; Palmtag, Juri; Prommer, Judith; Schnecker, Jörg; Shibistova, Olga; Takriti, Mounir; Urich, Tim; Richter, Andreas

    2018-03-01

    Arctic plant productivity is often limited by low soil N availability. This has been attributed to slow breakdown of N-containing polymers in litter and soil organic matter (SOM) into smaller, available units, and to shallow plant rooting constrained by permafrost and high soil moisture. Using 15N pool dilution assays, we here quantified gross amino acid and ammonium production rates in 97 active layer samples from four sites across the Siberian Arctic. We found that amino acid production in organic layers alone exceeded literature-based estimates of maximum plant N uptake 17-fold and therefore reject the hypothesis that arctic plant N limitation results from slow SOM breakdown. High microbial N use efficiency in organic layers rather suggests strong competition of microorganisms and plants in the dominant rooting zone. Deeper horizons showed lower amino acid production rates per volume, but also lower microbial N use efficiency. Permafrost thaw together with soil drainage might facilitate deeper plant rooting and uptake of previously inaccessible subsoil N, and thereby promote plant productivity in arctic ecosystems. We conclude that changes in microbial decomposer activity, microbial N utilization and plant root density with soil depth interactively control N availability for plants in the Arctic.

  11. Dietary potential renal Acid load in venezuelan children.

    PubMed

    López-Sayers, Mayerling; Bernal, Jennifer; López, Michelle

    2015-05-01

    Our aim was to determine and analyze the dietary PRAL and food composition pattern in apparently healthy children from 1 to 6 years of age. Parents of 52 children were selected by convenience, in an outpatient clinic of healthy children. Dietary quality and pattern was assessed by 24 hour recall and food frequency questionnaire. We focused on the intake of macronutrients and food groups, such as meats, dairy, fruits and vegetables. Nutrient intake was compared with national and international recommendations. PRAL was determined according to the method described by Remer and Manz. Descriptive statistics and correlations were applied. Dietary intake of proteins, milk and meat was high, while fruits and vegetables intake was low. PRAL was positive in 92% of the children and correlated (p<0.05) with intake of energy, proteins, fat, meat and dairy products. Protein intake was above 2.5 g/kg/day in 46.2% of the children. Food groups with the highest unbalance were meat and dairy products for excessive intake and fruits and vegetables regarding low intake, both of which represent risk factors for endogenous acid production. The diet of the children studied was characterized by an excessive acid load with the risk for the generation of systemic acidosis and its metabolic consequences. Copyright AULA MEDICA EDICIONES 2014. Published by AULA MEDICA. All rights reserved.

  12. Production of hydrogen, ethanol and volatile fatty acids from the seaweed carbohydrate mannitol.

    PubMed

    Xia, Ao; Jacob, Amita; Herrmann, Christiane; Tabassum, Muhammad Rizwan; Murphy, Jerry D

    2015-10-01

    Fermentative hydrogen from seaweed is a potential biofuel of the future. Mannitol, which is a typical carbohydrate component of seaweed, was used as a substrate for hydrogen fermentation. The theoretical specific hydrogen yield (SHY) of mannitol was calculated as 5 mol H2/mol mannitol (615.4 mL H2/g mannitol) for acetic acid pathway, 3 mol H2/mol mannitol (369.2 mL H2/g mannitol) for butyric acid pathway and 1 mol H2/mol mannitol (123.1 mL H2/g mannitol) for lactic acid and ethanol pathways. An optimal SHY of 1.82 mol H2/mol mannitol (224.2 mL H2/g mannitol) was obtained by heat pre-treated anaerobic digestion sludge under an initial pH of 8.0, NH4Cl concentration of 25 mM, NaCl concentration of 50mM and mannitol concentration of 10 g/L. The overall energy conversion efficiency achieved was 96.1%. The energy was contained in the end products, hydrogen (17.2%), butyric acid (38.3%) and ethanol (34.2%). Copyright © 2015 Elsevier Ltd. All rights reserved.

  13. Fatty acid analysis of Iranian junk food, dairy, and bakery products: Special attention to trans-fats

    PubMed Central

    Nazari, Bahar; Asgary, Sedigheh; Azadbakht, Leila

    2012-01-01

    Background: Low attention to dairy product consumptions and high intake of junk foods and bakery products might be related to high prevalence of chronic diseases because of their fat content and fatty acid composition. Objective: In this study we investigated the kind and amount of fatty acid content in Iranian junk foods, dairy, and bakery products Materials and Methods: Some common brands of Iranian’s junk foods, dairy, and bakery products were chosen randomly from different supermarkets in Iran. The amount of 10 g sample was considered for fatty acid analysis by gas chromatography equipment with flam ionization detector. Results: In this study stearic acid (C18:0) and palmitic (C16:0) acid have the highest amount among other saturated fatty acids in all groups. In junk foods and bakery products, the most common trans-fatty acid (TFA) is elaidic acid (C18:1 9t) with ranging from 2.4% to 18.5% and in dairy products vaccinic acid (C18:1 11t) has the high level of TFAs among others (2.1% to 11.5%). Conclusion: The amount of TFAs in Iranian junk foods and bakery products was in a high level. PMID:23825996

  14. Fatty acid analysis of Iranian junk food, dairy, and bakery products: Special attention to trans-fats.

    PubMed

    Nazari, Bahar; Asgary, Sedigheh; Azadbakht, Leila

    2012-10-01

    Low attention to dairy product consumptions and high intake of junk foods and bakery products might be related to high prevalence of chronic diseases because of their fat content and fatty acid composition. In this study we investigated the kind and amount of fatty acid content in Iranian junk foods, dairy, and bakery products. Some common brands of Iranian's junk foods, dairy, and bakery products were chosen randomly from different supermarkets in Iran. The amount of 10 g sample was considered for fatty acid analysis by gas chromatography equipment with flam ionization detector. In this study stearic acid (C18:0) and palmitic (C16:0) acid have the highest amount among other saturated fatty acids in all groups. In junk foods and bakery products, the most common trans-fatty acid (TFA) is elaidic acid (C18:1 9t) with ranging from 2.4% to 18.5% and in dairy products vaccinic acid (C18:1 11t) has the high level of TFAs among others (2.1% to 11.5%). The amount of TFAs in Iranian junk foods and bakery products was in a high level.

  15. Effects of temperature, salinity, light intensity, and pH on the eicosapentaenoic acid production of Pinguiococcus pyrenoidosus

    NASA Astrophysics Data System (ADS)

    Sang, Min; Wang, Ming; Liu, Jianhui; Zhang, Chengwu; Li, Aifen

    2012-06-01

    The effects of temperature, light intensity, salinity, and initial pH on the growth and fatty acid composition of Pinguiococcus pyrenoidosus 2078 were studied for eicosapentaenoic acid (EPA) production potential. The fatty acid composition was assayed by gas chromatography-mass spectrometry, which indicated that the main fatty acids were C14:0, C16:0 and EPA. The highest EPA percentage 20.83% of total fatty acids was obtained at 20°C with the temperature being set at 20, 24, and 28°C. Under different salinities and light intensities, the highest percentages of total polyunsaturated fatty acids (PUFAs) and EPA were 17.82% and 31.37% of total fatty acids, respectively, which were achieved at salinity 30 and 100 μmol photon m-2s-1 illumination. The highest percentages of total PUFAs and EPA were 38.75% and 23.13% of total fatty acids, respectively, which were reached at an initial pH of 6 with the test range being from 5.0 to 9.0.

  16. Effects of phosphoenolpyruvate carboxylase desensitization on glutamic acid production in Corynebacterium glutamicum ATCC 13032.

    PubMed

    Wada, Masaru; Sawada, Kazunori; Ogura, Kotaro; Shimono, Yuta; Hagiwara, Takuya; Sugimoto, Masakazu; Onuki, Akiko; Yokota, Atsushi

    2016-02-01

    Phosphoenolpyruvate carboxylase (PEPC) in Corynebacterium glutamicum ATCC13032, a glutamic-acid producing actinobacterium, is subject to feedback inhibition by metabolic intermediates such as aspartic acid and 2-oxoglutaric acid, which implies the importance of PEPC in replenishing oxaloacetic acid into the TCA cycle. Here, we investigated the effects of feedback-insensitive PEPC on glutamic acid production. A single amino-acid substitution in PEPC, D299N, was found to relieve the feedback control by aspartic acid, but not by 2-oxoglutaric acid. A simple mutant, strain R1, having the D299N substitution in PEPC was constructed from ATCC 13032 using the double-crossover chromosome replacement technique. Strain R1 produced glutamic acid at a concentration of 31.0 g/L from 100 g/L glucose in a jar fermentor culture under biotin-limited conditions, which was significantly higher than that of the parent, 26.0 g/L (1.19-fold), indicative of the positive effect of desensitized PEPC on glutamic acid production. Another mutant, strain DR1, having both desensitized PEPC and PYK-gene deleted mutations, was constructed in a similar manner using strain D1 with a PYK-gene deleted mutation as the parent. This mutation had been shown to enhance glutamic acid production in our previous study. Although marginal, strain D1 produced higher glutamic acid, 28.8 g/L, than ATCC13032 (1.11-fold). In contrast, glutamic acid production by strain DR-1 was elevated up to 36.9 g/L, which was 1.42-fold higher than ATCC13032 and significantly higher than the other three strains. The results showed a synergistic effect of these two mutations on glutamic acid production in C. glutamicum. Copyright © 2015 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  17. Effectiveness of acidic oxidative potential water in preventing bacterial infection in islet transplantation.

    PubMed

    Miyamoto, M; Inoue, K; Gu, Y; Hoki, M; Haji, S; Ohyanagi, H

    1999-01-01

    At a number of points in the current procedures of islet isolation and islet culture after the harvesting of donor pancreata, microorganisms could potentially infect the islet preparation. Furthermore, the use of islets from multiple donors can compound the risks of contamination of individual recipients. Acidic oxidative potential water (also termed electrolyzed strong acid solution, function water, or acqua oxidation water), which was developed in Japan, is a strong acid formed on the anode in the electrolysis of water containing a small amount of sodium chloride. It has these physical properties: pH, from 2.3 to 2.7; oxidative-reduction potential, from 1,000 to 1,100 mV; dissolved chlorine, from 30 to 40 ppm; and dissolved oxygen, from 10 to 30 ppm. Because of these properties, acidic oxidative potential water has strong bactericidal effects on all bacteria including methicillin-resistant Staphylococcus aureus (MRSA), viruses including HIV, HBV, HCV, CMV, and fungi as a result of the action of the active oxygen and active chlorine that it contains. We conducted this study to evaluate the effect of acidic oxidative potential water irrigation on bacterial contamination on the harvesting of porcine pancreata from slaughterhouses for islet xenotransplantation by counting the number of pancreatic surface bacteria using the Dip-slide method, and on the results of islet culture; and to evaluate the direct effect on isolated islets when it is used to prevent bacterial contamination by the static incubation test and by morphological examination. Direct irrigation of the pancreas by acidic oxidative potential water was found to be very effective in preventing bacterial contamination, but direct irrigation of isolated islets slightly decreased their viability and function.

  18. Increased production of omega-3 fatty acids protects retinal ganglion cells after optic nerve injury in mice.

    PubMed

    Peng, Shanshan; Shi, Zhe; Su, Huanxing; So, Kwok-Fai; Cui, Qi

    2016-07-01

    Injury to the central nervous system causes progressive degeneration of injured axons, leading to loss of the neuronal bodies. Neuronal survival after injury is a prerequisite for successful regeneration of injured axons. In this study, we investigated the effects of increased production of omega-3 fatty acids and elevation of cAMP on retinal ganglion cell (RGC) survival and axonal regeneration after optic nerve (ON) crush injury in adult mice. We found that increased production of omega-3 fatty acids in mice enhanced RGC survival, but not axonal regeneration, over a period of 3 weeks after ON injury. cAMP elevation promoted RGC survival in wild type mice, but no significant difference in cell survival was seen in mice over-producing omega-3 fatty acids and receiving intravitreal injections of CPT-cAMP, suggesting that cAMP elevation protects RGCs after injury but does not potentiate the actions of the omega-3 fatty acids. The observed omega-3 fatty acid-mediated neuroprotection is likely achieved partially through ERK1/2 signaling as inhibition of this pathway by PD98059 hindered, but did not completely block, RGC protection. Our study thus enhances our current understanding of neural repair after CNS injury, including the visual system. Copyright © 2016 Elsevier Ltd. All rights reserved.

  19. The effect of methanogenesis inhibition, inoculum and substrate concentration on hydrogen and carboxylic acids production from cassava wastewater.

    PubMed

    Amorim, Norma C S; Amorim, Eduardo L C; Kato, Mario T; Florencio, Lourdinha; Gavazza, Savia

    2018-02-01

    Manipueira is a carbohydrate-rich agro-industrial waste from cassava processing. It is considered well suitable for biotechnological processes, such as hydrogen and carboxylic acids production, due to the high content of easily degradable organic matter. However, the proper methanogenesis inhibition method, inoculum type, and organic loads are factors still limiting the processes. The objective in this work was to evaluate the effects of such factors on byproducts production in anaerobic reactors. Batch experiments were conducted with 2.3-L flasks during two operational phases. In the first phase (P1), inhibition of methanogens in the sludge was evaluated using acetylene (1% v/v of headspace) and heat treatment (120 °C, 1 atm for 30 min). In the second phase (P2), three inoculum types obtained from common anaerobic sludges (bovine rumen and sludges from municipal and textile industrial wastewater treatment plants) were individually assayed. P2 aimed to identify the best inoculum, based on hydrogen production ability, which was tested for three initial concentrations of manipueira in terms of chemical oxygen demand (COD) (10, 20 and 40 g O 2 /L). Results of P1 indicated that either acetylene or heat treatment efficiently inhibited methanogenesis, with no methane production. However, the maximum H 2 production potential by applying heat treatment (~ 563 mL) was more than twice compared with that by acetylene treatment (~ 257 mL); and butyrate was the main carboxylic acid by-product (~ 3 g/L). In P2 experiments after sludge heat treatment, the highest hydrogen yield (1.66 ± 0.07 mol H 2 /mol glucose) and caproic acid production (~ 2 g/L) were observed at 20 g O 2 /L of manipueira COD, when bovine rumen was the inoculum. The primary metabolic degradation products in all P2 experiments were ethanol, acetic, butyric, propionic and caproic acids. The finding of caproic acid detection indicated that the applied conditions in manipueira anaerobic

  20. Oleaginous yeast Yarrowia lipolytica culture with synthetic and food waste-derived volatile fatty acids for lipid production.

    PubMed

    Gao, Ruiling; Li, Zifu; Zhou, Xiaoqin; Cheng, Shikun; Zheng, Lei

    2017-01-01

    commercial biodiesel feedstock. This work demonstrated the feasibility of utilizing synthetic and food waste-derived VFA for lipid production by Y. lipolytica . The good adaptability of Y. lipolytica to the high temperature and acidic environment further illustrated its considerable potential for practical application.

  1. Volatile fatty acids production from marine macroalgae by anaerobic fermentation.

    PubMed

    Pham, Thi Nhan; Nam, Woo Joong; Jeon, Young Joong; Yoon, Hyon Hee

    2012-11-01

    Volatile fatty acids (VFAs) were produced from the marine macroalgae, Laminaria japonica, Pachymeniopsis elliptica, and Enteromorpha crinite by anaerobic fermentation using a microbial community derived from a municipal wastewater treatment plant. Methanogen inhibitor (iodoform), pH control, substrate concentration, and alkaline and thermal pretreatments affected VFA productivity. Acetic, propionic, and butyric acids were the main products. A maximum VFA concentration of 15.2g/L was obtained from 50 g/L of L. japonica in three days at 35°C and pH 6.5-7.0. Pretreatment with 0.5 N NaOH improved VFA productivity by 56% compared to control. The result shows the applicability of marine macroalgae as biomass feedstock for the production of VFAs which can be converted to mixed alcohol fuels. Copyright © 2012 Elsevier Ltd. All rights reserved.

  2. Enhanced D-lactic acid production from renewable resources using engineered Lactobacillus plantarum.

    PubMed

    Zhang, Yixing; Vadlani, Praveen V; Kumar, Amit; Hardwidge, Philip R; Govind, Revathi; Tanaka, Tsutomu; Kondo, Akihiko

    2016-01-01

    D-lactic acid is used as a monomer in the production of poly-D-lactic acid (PDLA), which is used to form heat-resistant stereocomplex poly-lactic acid. To produce cost-effective D-lactic acid by using all sugars derived from biomass efficiently, xylose-assimilating genes encoding xylose isomerase and xylulokinase were cloned into an L-lactate-deficient strain, Lactobacillus plantarum. The resulting recombinant strain, namely L. plantarum NCIMB 8826 ∆ldhL1-pLEM-xylAB, was able to produce D-lactic acid (at optical purity >99 %) from xylose at a yield of 0.53 g g(-1). Simultaneous utilization of glucose and xylose to produce D-lactic acid was also achieved by this strain, and 47.2 g L(-1) of D-lactic acid was produced from 37.5 g L(-1) glucose and 19.7 g L(-1) xylose. Corn stover and soybean meal extract (SBME) were evaluated as cost-effective medium components for D-lactic acid production. Optimization of medium composition using response surface methodology resulted in 30 % reduction in enzyme loading and 70 % reduction in peptone concentration. In addition, we successfully demonstrated D-lactic acid fermentation from corn stover and SBME in a fed-batch fermentation, which yielded 61.4 g L(-1) D-lactic acid with an overall yield of 0.77 g g(-1). All these approaches are geared to attaining high D-lactic acid production from biomass sugars to produce low-cost, highly thermostable biodegradable plastics.

  3. Cofactor and CO2 donor regulation involved in reductive routes for polymalic acid production by Aureobasidium pullulans CCTCC M2012223.

    PubMed

    Zou, Xiang; Tu, Guangwei; Zan, Zhanquan

    2014-10-01

    Polymalic acid (PMA) is a water-soluble polyester with many attractive properties for biomedical application. Its monomer L-malic acid is widely used in the food industry and also a potential C4 platform chemical. Cofactor and CO2 donor involved in the reductive routes were investigated for PMA production by Aureobasidium pullulans. Biotin as the key cofactor of pyruvate carboxylase was favor for the PMA biosynthesis. Na2CO3 as CO2 donor can obviously improved PMA titer when compared with no CO2 supplier NaOH, and also exhibit more advantages than the other donor CaCO3 because of its water-soluble characteristic. A combinational process with addition of biotin 70 mg/L and Na2CO3 as the CO2 donor was scaled-up in 50 L fermentor, achieving the high product 34.3 g/L of PMA and productivity of 0.41 g/L h. This process provides an efficient and economical way for PMA and malic acid production, and is promising for industrial application.

  4. Yarrowia lipolytica: a model yeast for citric acid production.

    PubMed

    Cavallo, Ema; Charreau, Hernán; Cerrutti, Patricia; Foresti, María Laura

    2017-12-01

    Every year more than 2 million tons of citric acid (CA) are produced around the world for industrial uses. Although initially extracted from citrus, the low profitability of the process and the increasing demand soon stimulated the search for more efficient methods to produce CA. Currently, most world CA demand (99%) is satisfied by fermentations with microorganisms, especially filamentous fungi and yeasts. CA production with yeasts has certain advantages over molds (e.g. higher productivity and easier cultivation), which in the last two decades have triggered a clear increase in publications and patents devoted to the use of yeasts in this field. Yarrowia lipolytica has become a model yeast that proved to be successful in different production systems. Considering the current interest evidenced in the literature, the most significant information on CA production using Y. lipolytica is summarized. The relevance on CA yields of key factors such as strains, media formulation, environmental conditions and production regimes is thoroughly discussed, with particular focus on increasing CA productivity. Besides, the possibility of tuning the mentioned variables to reduce concomitant isocitric acid production-the biggest disadvantage of using yeasts-is analyzed. Available methods for CA purification/quantification are also discussed. © FEMS 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  5. Unusal pattern of product inhibition: batch acetic acid fermentation

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

    Bar, R.; Gainer, J.L.; Kirwan, D.J.

    1987-04-20

    The limited tolerance of microorganisms to their metabolic products results in inhibited growth and product formation. The relationship between the specific growth rate, micro, and the concentration of an inhibitory product has been described by a number of mathematical models. In most cases, micro was found to be inversely proportional to the product concentration and invariably the rate of substrate utilization followed the same pattern. In this communication, the authors report a rather unusual case in which the formation rate of a product, acetic acid, increased with a decreasing growth rate of the microorganism, Acetobacter aceti. Apparently, a similar behaviormore » was mentioned in a review report with respect to Clostridium thermocellum in a batch culture but was not published in the freely circulating literature. The fermentation of ethanol to acetic acid, C/sub 2/H/sub 5/OH + O/sub 2/ = CH/sub 3/COOH + H/sub 2/O is clearly one of the oldest known fermentations. Because of its association with the commercial production of vinegar it has been a subject of extensive but rather technically oriented studies. Suprisingly, the uncommon uncoupling between the inhibited microbial growth and the product formation appears to have been unnoticed. 13 references.« less

  6. Response surface methodology for optimising the culture conditions for eicosapentaenoic acid production by marine bacteria.

    PubMed

    Abd Elrazak, Ahmed; Ward, Alan C; Glassey, Jarka

    2013-05-01

    Polyunsaturated fatty acids (PUFAs), especially eicosapentaenoic acid (EPA), are increasingly attracting scientific attention owing to their significant health-promoting role in the human body. However, the human body lacks the ability to produce them in vivo. The limitations associated with the current sources of ω-3 fatty acids from animal and plant sources have led to increased interest in microbial production. Bacterial isolate 717 was identified as a potential high EPA producer. As an important step in the process development of the microbial PUFA production, the culture conditions at the bioreactor scale were optimised for the isolate 717 using a response surface methodology exploring the significant effect of temperature, pH and dissolved oxygen and the interaction between them on the EPA production. This optimisation strategy led to a significant increase in the amount of EPA produced by the isolate under investigation, where the amount of EPA increased from 9 mg/g biomass (33 mg/l representing 7.6 % of the total fatty acids) to 45 mg/g (350 mg/l representing 25 % of the total fatty acids). To avoid additional costs associated with extreme cooling at large scale, a temperature shock experiment was carried out reducing the overall cooling time from the whole cultivation process to 4 h only prior to harvest. The ability of the organism to produce EPA under the complete absence of oxygen was tested revealing that oxygen is not critically required for the biosynthesis of EPA but the production improved in the presence of oxygen. The stability of the produced oil and the complete absence of heavy metals in the bacterial biomass are considered as an additional benefit of bacterial EPA compared to other sources of PUFA. To our knowledge this is the first report of a bacterial isolate producing EPA with such high yields making the large-scale manufacture much more economically viable.

  7. Purity-activity relationships of natural products: the case of anti-TB active ursolic acid.

    PubMed

    Jaki, Birgit U; Franzblau, Scott G; Chadwick, Lucas R; Lankin, David C; Zhang, Fangqiu; Wang, Yuehong; Pauli, Guido F

    2008-10-01

    The present study explores the variability of biological responses from the perspective of sample purity and introduces the concept of purity-activity relationships (PARs) in natural product research. The abundant plant triterpene ursolic acid (1) was selected as an exemplary natural product due to the overwhelming number yet inconsistent nature of its approximate 120 reported biological activities, which include anti-TB potential. Nine different samples of ursolic acid with purity certifications were obtained, and their purity was independently assessed by means of quantitative 1H NMR (qHNMR). Biological evaluation consisted of determining MICs against two strains of virulent Mycobacterium tuberculosis and IC50 values in Vero cells. Ab initio structure elucidation provided unequivocal structural confirmation and included an extensive 1H NMR spin system analysis, determination of nearly all J couplings and the complete NOE pattern, and led to the revision of earlier reports. As a net result, a sigmoid PAR profile of 1 was obtained, demonstrating the inverse correlation of purity and anti-TB bioactivity. The results imply that synergistic effects of 1 and its varying impurities are the likely cause of previously reported antimycobacterial potential. Generating PARs is a powerful extension of the routinely performed quantitative correlation of structure and activity ([Q]SAR). Advanced by the use of primary analytical methods such as qHNMR, PARs enable the elucidation of cases like 1 when increasing purity voids biological activity. This underlines the potential of PARs as a tool in drug discovery and synergy research and accentuates the need to routinely combine biological testing with purity assessment.

  8. Alpha-lipoic acid as a pleiotropic compound with potential therapeutic use in diabetes and other chronic diseases.

    PubMed

    Gomes, Marilia Brito; Negrato, Carlos Antonio

    2014-01-01

    Alpha-lipoic acid is a naturally occurring substance, essential for the function of different enzymes that take part in mitochondria's oxidative metabolism. It is believed that alpha-lipoic acid or its reduced form, dihydrolipoic acid have many biochemical functions acting as biological antioxidants, as metal chelators, reducers of the oxidized forms of other antioxidant agents such as vitamin C and E, and modulator of the signaling transduction of several pathways. These above-mentioned actions have been shown in experimental studies emphasizing the use of alpha-lipoic acid as a potential therapeutic agent for many chronic diseases with great epidemiological as well economic and social impact such as brain diseases and cognitive dysfunctions like Alzheimer disease, obesity, nonalcoholic fatty liver disease, burning mouth syndrome, cardiovascular disease, hypertension, some types of cancer, glaucoma and osteoporosis. Many conflicting data have been found concerning the clinical use of alpha-lipoic acid in the treatment of diabetes and of diabetes-related chronic complications such as retinopathy, nephropathy, neuropathy, wound healing and diabetic cardiovascular autonomic neuropathy. The most frequent clinical condition in which alpha-lipoic acid has been studied was in the management of diabetic peripheral neuropathy in patients with type 1 as well type 2 diabetes. Considering that oxidative stress, a imbalance between pro and antioxidants with excessive production of reactive oxygen species, is a factor in the development of many diseases and that alpha-lipoic acid, a natural thiol antioxidant, has been shown to have beneficial effects on oxidative stress parameters in various tissues we wrote this article in order to make an up-to-date review of current thinking regarding alpha-lipoic acid and its use as an antioxidant drug therapy for a myriad of diseases that could have potential benefits from its use.

  9. Fermentation Products of Solvent Tolerant Marine Bacterium Moraxella spp. MB1 and Its Biotechnological Applications in Salicylic Acid Bioconversion

    PubMed Central

    Wahidullah, Solimabi; Naik, Deepak N.; Devi, Prabha

    2013-01-01

    As part of a proactive approach to environmental protection, emerging issues with potential impact on the environment is the subject of ongoing investigation. One emerging area of environmental research concerns pharmaceuticals like salicylic acid, which is the main metabolite of various analgesics including aspirin. It is a common component of sewage effluent and also an intermediate in the degradation pathway of various aromatic compounds which are introduced in the marine environment as pollutants. In this study, biotransformation products of salicylic acid by seaweed, Bryopsis plumosa, associated marine bacterium, Moraxella spp. MB1, have been investigated. Phenol, conjugates of phenol and hydroxy cinnamic acid derivatives (coumaroyl, caffeoyl, feruloyl and trihydroxy cinnamyl) with salicylic acid (3–8) were identified as the bioconversion products by electrospray ionization mass spectrometry. These results show that the microorganism do not degrade phenolic acid but catalyses oxygen dependent transformations without ring cleavage. The degradation of salicylic acid is known to proceed either via gentisic acid pathway or catechol pathway but this is the first report of biotransformation of salicylic acid into cinnamates, without ring cleavage. Besides cinnamic acid derivatives (9–12), metabolites produced by the bacterium include antimicrobial indole (13) and β-carbolines, norharman (14), harman (15) and methyl derivative (16), which are beneficial to the host and the environment. PMID:24391802

  10. Efficient production of free fatty acids from soybean meal carbohydrates.

    PubMed

    Wang, Dan; Thakker, Chandresh; Liu, Ping; Bennett, George N; San, Ka-Yiu

    2015-11-01

    Conversion of biomass feedstock to chemicals and fuels has attracted increasing attention recently. Soybean meal, containing significant quantities of carbohydrates, is an inexpensive renewable feedstock. Glucose, galactose, and fructose can be obtained by enzymatic hydrolysis of soluble carbohydrates of soybean meal. Free fatty acids (FFAs) are valuable molecules that can be used as precursors for the production of fuels and other value-added chemicals. In this study, free fatty acids were produced by mutant Escherichia coli strains with plasmid pXZ18Z (carrying acyl-ACP thioesterase (TE) and (3R)-hydroxyacyl-ACP dehydratase) using individual sugars, sugar mixtures, and enzymatic hydrolyzed soybean meal extract. For individual sugar fermentations, strain ML211 (MG1655 fadD(-) fabR(-) )/pXZ18Z showed the best performance, which produced 4.22, 3.79, 3.49 g/L free fatty acids on glucose, fructose, and galactose, respectively. While the strain ML211/pXZ18Z performed the best with individual sugars, however, for sugar mixture fermentation, the triple mutant strain XZK211 (MG1655 fadD(-) fabR(-) ptsG(-) )/pXZ18Z with an additional deletion of ptsG encoding the glucose-specific transporter, functioned the best due to relieved catabolite repression. This strain produced approximately 3.18 g/L of fatty acids with a yield of 0.22 g fatty acids/g total sugar. Maximum free fatty acids production of 2.78 g/L with a high yield of 0.21 g/g was achieved using soybean meal extract hydrolysate. The results suggested that soybean meal carbohydrates after enzymatic treatment could serve as an inexpensive feedstock for the efficient production of free fatty acids. © 2015 Wiley Periodicals, Inc.

  11. Overexpression of ESBP6 improves lactic acid resistance and production in Saccharomyces cerevisiae.

    PubMed

    Sugiyama, Minetaka; Akase, Shin-Pei; Nakanishi, Ryota; Kaneko, Yoshinobu; Harashima, Satoshi

    2016-10-01

    Polylactic acid plastics are receiving increasing attention for the control of atmospheric CO2 emissions. Lactic acid, the building block for polylactic acid, is produced by fermentation technology from renewable carbon sources. The yeast Saccharomyces cerevisiae, harboring the lactate dehydrogenases gene (LDH), produces lactic acid at a large scale due to its strong acid resistance, to its simple nutritional requirements and to its ease of genetic engineering. Since improvement of lactic acid resistance is correlated with an increase of lactic acid production under non-neutralizing condition, we isolated a novel gene that enhances lactic acid resistance using a multi-copy yeast genomic DNA library. In this study, we identified the ESBP6 gene, which increases lactic acid resistance when overexpressed and which encodes a protein with similarity to monocarboxylate permeases. Although ESBP6 was not induced in response to lactic acid stress, it caused weak but reproducible sensitivity to lactic acid when disrupted. Furthermore, intracellular pH in the ESBP6 overexpressing strain was higher than that in the wild-type strain under lactic acid stressed condition, suggesting that Esbp6 plays some roles in lactic acid adaptation response. The ESBP6 overexpressing strain carrying the LDH gene induced 20% increase in lactic acid production compared with the wild-type strain carrying the LDH gene under non-neutralizing conditions. These results indicate that overexpression of ESBP6 provides a novel and useful tool to improve lactic acid resistance and lactic acid production in yeast. Copyright © 2016 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  12. Vinegar Production from Jabuticaba (Myrciaria jaboticaba) Fruit Using Immobilized Acetic Acid Bacteria

    PubMed Central

    Silva, Monique Suela; Cristina de Souza, Angélica; Magalhăes-Guedes, Karina Teixeira; Ribeiro, Fernanda Severo de Rezende; Schwan, Rosane Freitas

    2016-01-01

    Summary Cell immobilization comprises the retention of metabolically active cells inside a polymeric matrix. In this study, the production of jabuticaba (Myrciaria jaboticaba) vinegar using immobilized Acetobacter aceti and Gluconobacter oxydans cells is proposed as a new method to prevent losses of jabuticaba fruit surplus. The pulp of jabuticaba was processed and Saccharomyces cerevisiae CCMA 0200 was used to ferment the must for jabuticaba wine production. Sugars, alcohols (ethanol and glycerol) and organic acids were assayed by high-performance liquid chromatography. Volatile compounds were determined by gas chromatography-flame ionization detector. The ethanol content of the produced jabuticaba wine was approx. 74.8 g/L (9.5% by volume) after 168 h of fermentation. Acetic acid fermentation for vinegar production was performed using a mixed culture of immobilized A. aceti CCT 0190 and G. oxydans CCMA 0350 cells. The acetic acid yield was 74.4% and productivity was 0.29 g/(L·h). The vinegar had particularly high concentrations of citric (6.67 g/L), malic (7.02 g/L) and succinic (5.60 g/L) acids. These organic acids give a suitable taste and flavour to the vinegar. Seventeen compounds (aldehydes, higher alcohols, terpene, acetate, diether, furans, acids, ketones and ethyl esters) were identified in the jabuticaba vinegar. In conclusion, vinegar was successfully produced from jabuticaba fruits using yeast and immobilized mixed cultures of A. aceti and G. oxydans. To the best of our knowledge, this is the first study to use mixed culture of immobilized cells for the production of jabuticaba vinegar. PMID:27956867

  13. Vinegar Production from Jabuticaba (Myrciaria jaboticaba) Fruit Using Immobilized Acetic Acid Bacteria.

    PubMed

    Dias, Disney Ribeiro; Silva, Monique Suela; Cristina de Souza, Angélica; Magalhăes-Guedes, Karina Teixeira; Ribeiro, Fernanda Severo de Rezende; Schwan, Rosane Freitas

    2016-09-01

    Cell immobilization comprises the retention of metabolically active cells inside a polymeric matrix. In this study, the production of jabuticaba ( Myrciaria jaboticaba ) vinegar using immobilized Acetobacter aceti and Gluconobacter oxydans cells is proposed as a new method to prevent losses of jabuticaba fruit surplus. The pulp of jabuticaba was processed and Saccharomyces cerevisiae CCMA 0200 was used to ferment the must for jabuticaba wine production. Sugars, alcohols (ethanol and glycerol) and organic acids were assayed by high-performance liquid chromatography. Volatile compounds were determined by gas chromatography-flame ionization detector. The ethanol content of the produced jabuticaba wine was approx. 74.8 g/L (9.5% by volume) after 168 h of fermentation. Acetic acid fermentation for vinegar production was performed using a mixed culture of immobilized A. aceti CCT 0190 and G. oxydans CCMA 0350 cells. The acetic acid yield was 74.4% and productivity was 0.29 g/(L·h). The vinegar had particularly high concentrations of citric (6.67 g/L), malic (7.02 g/L) and succinic (5.60 g/L) acids. These organic acids give a suitable taste and flavour to the vinegar. Seventeen compounds (aldehydes, higher alcohols, terpene, acetate, diether, furans, acids, ketones and ethyl esters) were identified in the jabuticaba vinegar. In conclusion, vinegar was successfully produced from jabuticaba fruits using yeast and immobilized mixed cultures of A. aceti and G. oxydans . To the best of our knowledge, this is the first study to use mixed culture of immobilized cells for the production of jabuticaba vinegar.

  14. Ethanol Production by Selected Intestinal Microorganisms and Lactic Acid Bacteria Growing under Different Nutritional Conditions.

    PubMed

    Elshaghabee, Fouad M F; Bockelmann, Wilhelm; Meske, Diana; de Vrese, Michael; Walte, Hans-Georg; Schrezenmeir, Juergen; Heller, Knut J

    2016-01-01

    To gain some specific insight into the roles microorganisms might play in non-alcoholic fatty liver disease (NAFLD), some intestinal and lactic acid bacteria and one yeast (Anaerostipes caccae, Bacteroides thetaiotaomicron, Bifidobacterium longum, Enterococcus fecalis, Escherichia coli, Lactobacillus acidophilus, Lactobacillus fermentum, Lactobacillus plantarum, Weissella confusa, Saccharomyces cerevisiae) were characterized by high performance liquid chromatography for production of ethanol when grown on different carbohydrates: hexoses (glucose and fructose), pentoses (arabinose and ribose), disaccharides (lactose and lactulose), and inulin. Highest amounts of ethanol were produced by S. cerevisiae, L. fermentum, and W. confusa on glucose and by S. cerevisiae and W. confusa on fructose. Due to mannitol-dehydrogenase expressed in L. fermentum, ethanol production on fructose was significantly (P < 0.05) reduced. Pyruvate and citrate, two potential electron acceptors for regeneration of NAD(+)/NADP(+), drastically reduced ethanol production with acetate produced instead in L. fermentum grown on glucose and W. confusa grown on glucose and fructose, respectively. In fecal slurries prepared from feces of four overweight volunteers, ethanol was found to be produced upon addition of fructose. Addition of A. caccae, L. acidophilus, L. fermentum, as well as citrate and pyruvate, respectively, abolished ethanol production. However, addition of W. confusa resulted in significantly (P < 0.05) increased production of ethanol. These results indicate that microorganisms like W. confusa, a hetero-fermentative, mannitol-dehydrogenase negative lactic acid bacterium, may promote NAFLD through ethanol produced from sugar fermentation, while other intestinal bacteria and homo- and hetero-fermentative but mannitol-dehydrogenase positive lactic acid bacteria may not promote NAFLD. Also, our studies indicate that dietary factors interfering with gastrointestinal microbiota and microbial

  15. Lactic acid production from xylose by engineered Saccharomyces cerevisiae without PDC or ADH deletion

    USDA-ARS?s Scientific Manuscript database

    Production of lactic acid from renewable sugars has received growing attention as lactic acid can be used for making renewable and bio-based plastics. However, most prior studies have focused on production of lactic acid from glucose despite cellulosic hydrolysates contain xylose as well as glucose....

  16. Method for the production of dicarboxylic acids

    DOEpatents

    Nghiem, N.P.; Donnelly, M.; Millard, C.S.; Stols, L.

    1999-02-09

    The present invention is an economical fermentation method for the production of carboxylic acids comprising the steps of (a) inoculating a medium having a carbon source with a carboxylic acid-producing organism; (b) incubating the carboxylic acid-producing organism in an aerobic atmosphere to promote rapid growth of the organism thereby increasing the biomass of the organism; (c) controllably releasing oxygen to maintain the aerobic atmosphere; (d) controllably feeding the organism having increased biomass with a solution containing the carbon source to maintain the concentration of the carbon source within the medium of about 0.5 g/l up to about 1 g/l; (e) depriving the aerobic atmosphere of oxygen to produce an anaerobic atmosphere to cause the organism to undergo anaerobic metabolism; (f) controllably feeding the organism having increased biomass a solution containing the carbon source to maintain the concentration of the carbon source within the medium of {>=}1 g/l; and (g) converting the carbon source to carboxylic acids using the anaerobic metabolism of the organism. 7 figs.

  17. Method for the production of dicarboxylic acids

    DOEpatents

    Nghiem, Nhuan Phu; Donnelly, Mark; Millard, Cynthia S.; Stols, Lucy

    1999-01-01

    The present invention is an economical fermentation method for the production of carboxylic acids comprising the steps of a) inoculating a medium having a carbon source with a carboxylic acid-producing organism; b) incubating the carboxylic acid-producing organism in an aerobic atmosphere to promote rapid growth of the organism thereby increasing the biomass of the organism; c) controllably releasing oxygen to maintain the aerobic atmosphere; d) controllably feeding the organism having increased biomass with a solution containing the carbon source to maintain the concentration of the carbon source within the medium of about 0.5 g/L up to about 1 g/L; e) depriving the aerobic atmosphere of oxygen to produce an anaerobic atmosphere to cause the organism to undergo anaerobic metabolism; f) controllably feeding the organism having increased biomass a solution containing the carbon source to maintain the concentration of the carbon source within the medium of .gtoreq.1 g/L; and g) converting the carbon source to carboxylic acids using the anaerobic metabolism of the organism.

  18. Efficient production of l-lactic acid from hydrolysate of Jerusalem artichoke with immobilized cells of Lactococcus lactis in fibrous bed bioreactors.

    PubMed

    Shi, Zhouming; Wei, Peilian; Zhu, Xiangcheng; Cai, Jin; Huang, Lei; Xu, Zhinan

    2012-10-10

    Hydrolysate of Jerusalem artichoke was applied for the production of l-lactic acid by immobilized Lactococcus lactis cells in a fibrous bed bioreactor system. Preliminary experiments had indicated that the high quality hydrolysate, which was derived from the 40 min acid treatment at 95 °C and pH 1.8, was sufficient to support the cell growth and synthesis of l-lactic acid. With the addition of 5 g/l yeast extract, the fermentative performance of free cell system was evidently improved. After the basal settlement of hydrolysate based fermentation, the batch mode and the fed-batch mode fermentation were carried out in the free cell system and the fibrous bed bioreactor system, respectively. In all cases the immobilized cells presented the superior ability to produce l-lactic acid. The comparison of batch mode and fed-batch mode also indicated that the growth-limiting feeding strategy could reduce the lag phase of fermentation process and enhance the production of l-lactic acid. The achieved maximum concentration of l-lactic acid was 142 g/l in the fed-batch mode. Subsequent repeated-batch fermentation of the fibrous bed bioreactor system had further exhibited the persistence and stability of this system for the high production of l-lactic acid in a long term. Our work suggested the great potential of the fibrous bed bioreactor system and hydrolysate of J. artichoke in the economical production of l-lactic acid at industrial scale. Copyright © 2012 Elsevier Inc. All rights reserved.

  19. Citric acid production by Koji fermentation using banana peel as a novel substrate.

    PubMed

    Karthikeyan, Alagarsamy; Sivakumar, Nallusamy

    2010-07-01

    The growing demand for citric acid and the current need for alternative sources have encouraged biotechnologists to search for novel and economical substrates. Koji fermentation was conducted using the peels of banana (Musa acuminata) as an inexpensive substrate for the production of citric acid using Aspergillus niger. Various crucial parameters that affect citric acid production such as moisture content, temperature, pH, inoculum level and incubation time were quantified. Moisture (70%), 28 degrees C temperature, an initial pH 3, 10(8) spores/ml as inoculum and 72h incubation was found to be suitable for maximum citric acid production by A. niger using banana peel as a substrate. Copyright (c) 2010 Elsevier Ltd. All rights reserved.

  20. Butanol production by a Clostridium beijerinckii mutant with high ferulic acid tolerance.

    PubMed

    Liu, Jun; Guo, Ting; Wang, Dong; Xu, Jiahui; Ying, Hanjie

    2016-09-01

    A mutant strain of Clostridium beijerinckii, with high tolerance to ferulic acid, was generated using atmospheric pressure glow discharge and high-throughput screening of C. beijerinckii NCIMB 8052. The mutant strain M11 produced 7.24 g/L of butanol when grown in P2 medium containing 30 g/L of glucose and 0.5 g/L of ferulic acid, which is comparable to the production from non-ferulic acid cultures (8.11 g/L of butanol). When 0.8 g/L of ferulic acid was introduced into the P2 medium, C. beijerinckii M11 grew well and produced 4.91 g/L of butanol. Both cell growth and butanol production of C. beijerinckii M11 were seriously inhibited when 0.9 g/L of ferulic acid was added into the P2 medium. Furthermore, C. beijerinckii M11 could produce 6.13 g/L of butanol using non-detoxified hemicellulosic hydrolysate from diluted sulfuric acid-treated corn fiber (SAHHC) as the carbon source. These results demonstrate that C. beijerinckii M11 has a high ferulic acid tolerance and is able to use non-detoxified SAHHC for butanol production. © 2015 International Union of Biochemistry and Molecular Biology, Inc.