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1

Membrane Extraction for Detoxification of Biomass Hydrolysates  

SciTech Connect

Membrane extraction was used for the removal of sulfuric acid, acetic acid, 5-hydroxymethyl furfural and furfural from corn stover hydrolyzed with dilute sulfuric acid. Microporous polypropylene hollow fiber membranes were used. The organic extractant consisted of 15% Alamine 336 in: octanol, a 50:50 mixture of oleyl alcohol:octanol or oleyl alcohol. Rapid removal of sulfuric acid, 5-hydroxymethyl and furfural was observed. The rate of acetic acid removal decreased as the pH of the hydrolysate increased. Regeneration of the organic extractant was achieved by back extraction into an aqueous phase containing NaOH and ethanol. A cleaning protocol consisting of flushing the hydrolysate compartment with NaOH and the organic phase compartment with pure organic phase enabled regeneration and reuse of the module. Ethanol yields from hydrolysates detoxified by membrane extraction using 15% Alamine 336 in oleyl alcohol were about 10% higher than those from hydrolysates detoxified using ammonium hydroxide treatment.

Grzenia, D. L.; Schell, D. J.; Wickramasinghe, S. R.

2012-05-01

2

Biological detoxification of different hemicellulosic hydrolysates using Issatchenkia occidentalis CCTCC M 206097 yeast.  

PubMed

This work had as its main objective to contribute to the development of a biological detoxification of hemicellulose hydrolysates obtained from different biomass plants using Issatchenkia occidentalis CCTCC M 206097 yeast. Tests with hemicellulosic hydrolysate of sugarcane bagasse in different concentrations were carried out to evaluate the influence of the hydrolysate concentration on the inhibitory compounds removal from the sugarcane bagasse hydrolysate, without reduction of sugar concentration. The highest reduction values of inhibitors concentration and less sugar losses were observed when the fivefold concentrated hydrolysate was treated by the evaluated yeast. In these experiments it was found that the high sugar concentrations favored lower sugar consumption by the yeast. The highest concentration reduction of syringaldehyde (66.67%), ferulic acid (73.33%), furfural (62%), and 5-HMF (85%) was observed when the concentrated hydrolysate was detoxified by using this yeast strain after 24 h of experimentation. The results obtained in this work showed the potential of the yeast Issatchenkia occidentalis CCTCC M 206097 as detoxification agent of hemicellulosic hydrolysate of different biomass plants. PMID:20844925

Fonseca, Bruno Guedes; Moutta, Rondinele de Oliveira; Ferraz, Flavio de Oliveira; Vieira, Emílio Rosa; Nogueira, Andrei Santini; Baratella, Bruno Fernandes; Rodrigues, Luiz Carlos; Hou-Rui, Zhang; da Silva, Sílvio Silvério

2011-01-01

3

Ethanol production using a soy hydrolysate-based medium or a yeast autolysate-based medium  

DOEpatents

This invention presents a method for the production of ethanol that utilizes a soy hydrolysate-based nutrient medium or a yeast autolysate-based medium nutrient medium in conjunction with ethanologenic bacteria and a fermentable sugar for the cost-effective production of ethanol from lignocellulosic biomass. The invention offers several advantages over presently available media for use in ethanol production, including consistent quality, lack of toxins and wide availability.

Ingram, Lonnie O. (Gainesville, FL)

2000-01-01

4

Molecular mechanisms of yeast tolerance and in situ detoxification of lignocellulose hydrolysates  

Microsoft Academic Search

Pretreatment of lignocellulose biomass for biofuel production generates inhibitory compounds that interfere with microbial\\u000a growth and subsequent fermentation. Remediation of the inhibitors by current physical, chemical, and biological abatement\\u000a means is economically impractical, and overcoming the inhibitory effects of lignocellulose hydrolysate poses a significant\\u000a technical challenge for lower-cost cellulosic ethanol production. Development of tolerant ethanologenic yeast strains has\\u000a demonstrated the

Z. Lewis Liu

2011-01-01

5

Anti-stress effects of chewing gum prepared with yeast hydrolysate  

Microsoft Academic Search

In this study, we investigated the anti-stress effects of chewing gum prepared with yeast hydrolysate (SCP) in the general\\u000a Korean population using heart rate value (HRV) analysis and the Beck depression inventory (BDI) and Beck anxiety inventory\\u000a (BAI). Four different kinds of chewing gum (weight 960 ± 2 mg) were designed: three with different concentrations of SCP (30,\\u000a 85, and 250 mg\\/piece) combined with

Hyung Joo Suh; Seong Yeong Kim; Un Jae Chang; Jin Man Kim

2008-01-01

6

Bioconversion of corncob acid hydrolysate into microbial oil by the oleaginous yeast Lipomyces starkeyi.  

PubMed

For the first time, corncob acid hydrolysate was used for microbial oil production by the oleaginous yeast Lipomyces starkeyi. After hydrolysis by dilute sulfuric acid, corncob could turn into an acid hydrolysate with a sugar concentration of about 42.3 g/L. Detoxified by overliming and absorption with activated carbon, the corncob hydrolysate could be used by L. starkeyi efficiently that a total biomass of 17.2 g/L with a lipid content of 47.0 % (corresponding to a lipid yield of 8.1 g/L) and a lipid coefficient of 20.9 could be obtained after cultivation on the corncob hydrolysate for 8 days. Therefore, L. starkeyi is a promising strain for microbial oil production from lignocellulosic biomass. Glucose and xylose were used by L. starkeyi simultaneously during lipid fermentation while arabinose could not be utilized by it. Besides, the lipid composition of L. starkeyi was similar to that of vegetable oils; thus, it is a promising feedstock for biodiesel production. PMID:24343368

Huang, Chao; Chen, Xue-Fang; Yang, Xiao-Yan; Xiong, Lian; Lin, Xiao-Qing; Yang, Juan; Wang, Bo; Chen, Xin-De

2014-02-01

7

Oil production by oleaginous yeasts using the hydrolysate from pretreatment of wheat straw with dilute sulfuric acid  

Microsoft Academic Search

This paper explores the use of the hydrolysate from the dilute sulfuric acid pretreatment of wheat straw for microbial oil production. The resulting hydrolysate was composed of pentoses (24.3g\\/L) and hexoses (4.9g\\/L), along with some other degradation products, such as acetic acid, furfural, and hydroxymethylfurfural (HMF). Five oleaginous yeast strains, Cryptococcus curvatus, Rhodotorula glutinis, Rhodosporidium toruloides, Lipomyces starkeyi, and Yarrowia

Xiaochen Yu; Yubin Zheng; Kathleen M. Dorgan; Shulin Chen

2011-01-01

8

Antifungal effects of hydrolysable tannins and related compounds on dermatophytes, mould fungi and yeasts.  

PubMed

A series of hydrolysable tannins and related compounds was evaluated for antifungal activities against filamentous fungi (Epidermophyton floccosum; Microsporum canis; Microsporum gypseum; Trichophyton mentagrophytes; Trichophyton rubrum; Trichophyton tonsurans; Trichophyton terrestre; Penicillium italicum; Aspergillus fumigatus; Mucor racemosus; Rhizopus nigricans) and opportunistic yeasts (Candida albicans; Candida glabrata; Candidata krusei; Cryptococcus neoformans), using the agar dilution method. While all samples had no activity against the filamentous fungi in concentrations of 1.1-5.9 microM (1000 microg/ml), the phenolic compounds displayed significant potencies against all the opportunistic yeasts tested but C. albicans, with minimum inhibitory concentrations ranging from 0.02 to 0.1 microM (16-125 microg/ml). Although the presence of galloyl groups in flavonoids did not necessarily produce activity, this structural element, an HHDP moiety or its oxidatively modified entity proved to be an important structural feature of hydrolysable tannins. Comparison of dilution methods provided strong evidence of dependence of MIC values on the test method. Employing the microdilution broth method, the ellagitannin corilagin (MIC 0.8 nM) was found to be similarly potentially active as amphotericin B (MIC 0.5 nM) and sertaconazole (MIC 0.9 nM) against Candida glabrata strains. The order of effectiveness observed being 64- and 4-8-fold increased for corilagin and the reference compounds respectively, when compared with that of the agar dilution test. PMID:10928561

Latté, K P; Kolodziej, H

2000-01-01

9

Oil production by oleaginous yeasts using the hydrolysate from pretreatment of wheat straw with dilute sulfuric acid.  

PubMed

This paper explores the use of the hydrolysate from the dilute sulfuric acid pretreatment of wheat straw for microbial oil production. The resulting hydrolysate was composed of pentoses (24.3g/L) and hexoses (4.9 g/L), along with some other degradation products, such as acetic acid, furfural, and hydroxymethylfurfural (HMF). Five oleaginous yeast strains, Cryptococcus curvatus, Rhodotorula glutinis, Rhodosporidium toruloides, Lipomyces starkeyi, and Yarrowia lipolytica, were evaluated by using this hydrolysate as substrates. The results showed that all of these strains could use the detoxified hydrolysate to produce lipids while except R. toruloides non-detoxified hydrolysate could also be used for the growth of all of the selective yeast strains. C. curvatus showed the highest lipid concentrations in medium on both the detoxified (4.2g/L) and non-detoxified (5.8 g/L) hydrolysates. And the inhibitory effect studies on C. curvatus indicated HMF had insignificant impacts at a concentration of up to 3g/L while furfural inhibited cell growth and lipid content by 72.0% and 62.0% at 1g/L, respectively. Our work demonstrates that lipid production is a promising alternative to utilize hemicellulosic sugars obtained during pretreatment of lignocellulosic materials. PMID:21463940

Yu, Xiaochen; Zheng, Yubin; Dorgan, Kathleen M; Chen, Shulin

2011-05-01

10

Downstream Processes for Aqueous Enzymatic Extraction of Rapeseed Oil and Protein Hydrolysates  

Microsoft Academic Search

Downstream processes following aqueous enzymatic extraction (AEE) of rapeseed oil and protein hydrolysates were developed\\u000a to enhance the oil and protein yields as well as to purify the protein hydrolysates. The wet precipitate (meal residue) from\\u000a the AEE was washed with twofold water at 60 °C, pH 11 for 1 h. Emulsions from the AEE and the washing step were pooled and

Shao Bing Zhang; Zhang Wang; Shi Ying Xu

2007-01-01

11

Ethanol production from concentrated food waste hydrolysates with yeast cells immobilized on corn stalk.  

PubMed

The aim of the present study was to examine ethanol production from concentrated food waste hydrolysates using whole cells of S. cerevisiae immobilized on corn stalks. In order to improve cell immobilization efficiency, biological modification of the carrier was carried out by cellulase hydrolysis. The results show that proper modification of the carrier with cellulase hydrolysis was suitable for cell immobilization. The mechanism proposed, cellulase hydrolysis, not only increased the immobilized cell concentration, but also disrupted the sleek surface to become rough and porous, which enhanced ethanol production. In batch fermentation with an initial reducing sugar concentration of 202.64 ± 1.86 g/l, an optimal ethanol concentration of 87.91 ± 1.98 g/l was obtained using a modified corn stalk-immobilized cell system. The ethanol concentration produced by the immobilized cells was 6.9% higher than that produced by the free cells. Ethanol production in the 14th cycle repeated batch fermentation demonstrated the enhanced stability of the immobilized yeast cells. Under continuous fermentation in an immobilized cell reactor, the maximum ethanol concentration of 84.85 g/l, and the highest ethanol yield of 0.43 g/g (of reducing sugar) were achieved at hydraulic retention time (HRT) of 3.10 h, whereas the maximum volumetric ethanol productivity of 43.54 g/l/h was observed at a HRT of 1.55 h. PMID:22395912

Yan, Shoubao; Chen, Xiangsong; Wu, Jingyong; Wang, Pingchao

2012-05-01

12

Development of a yeast strain for xylitol production without hydrolysate detoxification as part of the integration of co-product generation within the lignocellulosic ethanol process.  

PubMed

The present study verified an applicable technology of xylitol bioconversion as part of the integration of co-product generation within second-generation bioethanol processes. A newly isolated yeast strain, Candida tropicalis JH030, was shown to have a capacity for xylitol production from hemicellulosic hydrolysate without detoxification. The yeast gives a promising xylitol yield of 0.71 g(p) g(s)(-1) from non-detoxified rice straw hydrolysate that had been prepared by the dilute acid pretreatment under severe conditions. The yeast's capacity was also found to be practicable with various other raw materials, such as sugarcane bagasse, silvergrass, napiergrass and pineapple peel. The lack of a need to hydrolysate detoxification enhances the potential of this newly isolated yeast for xylitol production and this, in turn, has the capacity to improve economics of lignocellulosic ethanol production. PMID:21095119

Huang, Chiung-Fang; Jiang, Yi-Feng; Guo, Gia-Luen; Hwang, Wen-Song

2011-02-01

13

Preparation of extracts from yeast.  

PubMed

Because yeast is exceptionally well suited to genetic analysis, both classical and molecular, it is an attractive system for expressing recombinant animal proteins for purification purposes. Methods available for lysing yeast cells include autolysis, pressure cells (e.g., French press), abrasives (glass bead vortexing), and enzymatic lysis (e.g., zymolase). One of the simplest methods, discussed in this protocol, involves the abrasive action of well-agitated glass beads. This is a very effective method for both low volumes (e.g., <1 mL using a microcentrifuge tube) and many liters using a specialized DynoMill apparatus. Cell breakage is typically >95%, as assessed by phase-contrast microscopy. PMID:21205845

Simpson, Richard J

2011-01-01

14

21 CFR 172.590 - Yeast-malt sprout extract.  

... 3 2014-04-01 2014-04-01 false Yeast-malt sprout extract. 172.590 Section 172...Flavoring Agents and Related Substances § 172.590 Yeast-malt sprout extract. Yeast-malt sprout extract, as described in this...

2014-04-01

15

Growth inhibition of thermotolerant yeast, Kluyveromyces marxianus, in hydrolysates from cassava pulp.  

PubMed

In this study, we report the inhibition of Kluyveromyces marxianus TISTR5925 growth and ethanol fermentation in the presence of furan derivatives and weak acids (acetic acid and lactic acid) at high temperatures. Cassava pulp, obtained as the waste from starch processing, was collected from 14 starch factories located in several provinces of Thailand. At a high temperature (42 °C), the cassava pulp hydrolysate from some starch factories strongly inhibited growth and ethanol production of both K. marxianus (strain TISTR5925) and Saccharomyces cerevisiae (strain K3). HPLC detected high levels of lactic acid and acetic acid in the hydrolysates, suggesting that these weak acids impaired the growth of K. marxianus at high temperature. We isolated Trp-requiring mutants that had reduced tolerance to acetic acid compared to the wild-type. This sensitivity to acetic acid was suppressed by supplementation of the medium with tryptophan. PMID:24781978

Rugthaworn, Prapassorn; Murata, Yoshinori; Machida, Masashi; Apiwatanapiwat, Waraporn; Hirooka, Akiko; Thanapase, Warunee; Dangjarean, Hatairat; Ushiwaka, Satoru; Morimitsu, Kozo; Kosugi, Akihiko; Arai, Takamitsu; Vaithanomsat, Pilanee

2014-07-01

16

Detection of pyrimidine dimers in hydrolysates of yeast DNA by high voltage paper electrophoresis  

Microsoft Academic Search

A simplified procedure for studying pyrimidine dimer induction and excision in yeast DNA has been developed. It involved the use of [14C] uracil as a labelled precursor of both RNA and DNA, followed by efficient removal of RNA. Acid-precipitable DNA was hydrolyzed to release pyrimidine bases and these were separated by high voltage paper electrophoresis. Wild type cells of Schizosaccharomyces

H. C. Birnboim; A. Nasim

1974-01-01

17

Charcoal-Yeast Extract Agar: Primary Isolation Mediumfor Legionella pneumophila  

Microsoft Academic Search

Charcoal-yeast extract agar isa new bacteriological mediumthatsupports excellent growth oftheLegionella pneumophila. Itresults frommodifications madeinan existing L.pneumophila medium,F-Gagar.Yeastextract, instead of an acidhydrolysate ofcasein, servesastheprotein source.Beefextractives and starch are notadded. Activated charcoal (Norit A or Norit SG)isincluded at 0.20%(wt\\/vol). Comparison ofcharcoal-yeast extract andF-Gagars showedthat a greater numberofcolony-forming units ofL.pneumophila was recovered from astandardized tissue inoculum on charcoal-yeast extract agar(4.35 x 106colony- forning

JAMES C. FEELEY; ROBERT J. GIBSON; GEORGE W. GORMAN; NANCY C. LANGFORD; J. KAMILE RASHEED; DON C. MACKEL; WILLIAM B. BAINE

1979-01-01

18

Yeast hydrolysate protects cartilage via stimulation of type II collagen synthesis and suppression of MMP-13 production.  

PubMed

Type II collagen (COL II) is one of the primary components of hyaline cartilage and plays a key role in maintaining chondrocyte function. COL II is the principal target of destruction, and matrix metalloproteases (MMPs) have a major role in arthritis. In the present study, we investigated the chondroctye protection effects of specific fraction of yeast hydrolysate ((10-30?kDa molecular weight peptides). The mRNA expression of COL II was significantly increased in the YH-treated group compared to the control at concentrations above 50?µg/ml, respectively. The 200?µg/ml YH-treated group (3.43?±?0.23?µg/ml) showed significantly reduced glycosaminoglycan (GAG) degradation relative to that in the interleukin-1? (IL-1?)-treated control group (4.72?±?0.05?µg/ml). In the YH-treated group, MMP-13 level was significantly decreased in a dose-dependent manner compared to the IL-1?-treated group without YH treatment. However, MMP-1 and MMP-3 level were not different from that of control. Under the same conditions, we also examined mRNA levels of COL II. The mRNA expression of COL II was significantly higher in the YH-treated group than in the IL-1?-treated control group at concentrations above 100?µg/ml. In conclusion, YH stimulated COL II synthesis and significantly inhibited MMP-13 and GAG degradation caused by IL-1? treatment. PMID:23070893

Lee, Hyun-Sun; Park, So Yeon; Park, Yooheon; Bae, Song Hwan; Suh, Hyung Joo

2013-09-01

19

Stimulation of osteoblastic differentiation and mineralization in MC3T3-E1 cells by yeast hydrolysate.  

PubMed

In a previous study, it was reported that yeast hydrolysate (YH) was effective in promoting bone growth in Sprague-Dawley (SD) rats. To further clarify the mechanism of YH, the effects of YH on proliferation, differentiation and gene expression in vitro were investigated using osteoblastic cell lines (MC3T3-E1). Cell proliferation increased significantly as much as 110% of the basal value when cells were treated with 100?µg/mL of YH. Alkaline phosphatase (ALP) activity increased significantly with a YH concentration of 25-100?µg/mL, and the activity increased 152% that of the control at 100?µg/mL. The calcium content increased as much as 129% at 100?µg/mL YH. The gene expression levels of ALP and collagen type II (COL II) significantly increased approximately 1.3-fold and 1.7-fold of control, respectively, at 100?µg/mL. YH increased significantly the mRNA level of bone sialoprotein (BSP) but not in a dose-dependent manner. The mRNA levels of bone morphogenetic proteins (BMP)-2, BMP-4, collagen type I (COL I) and osteonectin (ON) did not increase. In summary, YH increased the proliferation of osteoblasts and directly stimulated ALP and bone matrix proteins (e.g. BSP, COL II), and these increases trigger osteoblastic differentiation (e.g. mineralized nodule formation). PMID:21077261

Lee, Hyun-Sun; Jung, Eun-Young; Bae, Song Hwan; Kwon, Ki Han; Kim, Jin-Man; Suh, Hyung Joo

2011-05-01

20

In vitro antimycotic activity of some plant extracts towards yeast and yeast-like strains.  

PubMed

As part of screening aimed at the selection of novel antimycotic compounds of vegetable origin, leaf extracts of Camellia sinensis L., Cupressus sempervirens L. and Pistacia lentiscus L. and the seed extract of Glycine soja Sieb. et Zucc. were tested against yeast and yeast-like species implicated in human mycoses. Of the extracts only those of C. sinensis (obtained from a commercial preparation of green tea) exhibited broad activity towards Candida glabrata, Clavispora lusitatiae, Cryptococcus laurentii, Filobasidiella neoformans, Issatchenkia orientalis, Saccharomyces cerevisiae and Prototheca wickerhamii strains. MICs ranging from 300 to 4800 microg extract/mL (corresponding to 130-2010 microg/mL total polyphenols) were observed. Concentrations of the C. sinensis extract over 25 000 microg/mL caused a rapid decrease of viable cells of Fil. neoformans and its activity was dose-dependent. Tests carried out using the pure polyphenols present in C. sinensis extract composition, showed that only epicatechin-3-O-gallate (ECG) and epigallocatechin-3-O-gallate (EGCG) possess antimycotic activity. PMID:15798996

Turchetti, B; Pinelli, P; Buzzini, P; Romani, A; Heimler, D; Franconi, F; Martini, A

2005-01-01

21

A rapid and simple method for extracting yeast mitochondrial DNA  

Microsoft Academic Search

A rapid method for the extraction of yeast mitochondrial DNA (mtDNA) is described. In comparison with previous methods, it simplifies several steps, does not require either the isolation of mitochondria or phenol treatment and is less time consuming. This protocol gives a high yield of pure mtDNA (50–120 µg from a 100-ml culture), which can be directly used in various

Ali Gargouri; M. Curie

1989-01-01

22

Optimization of pullulan production from hydrolysed potato starch waste by response surface methodology  

Microsoft Academic Search

The production of pullulan from hydrolysed potato starch waste by Aureobasidium pullulans P56 was investigated. The liquefaction of potato starch was done by Ca-alginate immobilized amyloglucosidase and pullulanase enzymes in a packed bed bioreactor. Various organic nitrogen sources were tested and none of the nitrogen sources gave pullulan concentrations as high as that obtained with yeast extract. Response surface methodology

Yekta Göksungur; Pürlen Uzuno?ullar?; Seval Da?ba?l?

2011-01-01

23

Autolysis of the red yeast Phaffia rhodozyma: A potential tool to facilitate extraction of astaxanthin  

Microsoft Academic Search

Distilled water and 0.02 molar citrate buffer pH 7.0, are suitable autolysing systems for the red yeast P. rhodozyma. Autolysis renders astaxanthin extractable from the yeast. Of six strains of the yeast tested, 67–484 was most susceptible to autolysis.

R. N. Okagbue; M. J. Lewis

1984-01-01

24

Ethanol production by Saccharomyces cerevisiae using lignocellulosic hydrolysate from Chrysanthemum waste degradation.  

PubMed

Ethanol production derived from Saccharomyces cerevisiae fermentation of a hydrolysate from floriculture waste degradation was studied. The hydrolysate was produced from Chrysanthemum (Dendranthema grandiflora) waste degradation by Pleurotus ostreatus and characterized to determine the presence of compounds that may inhibit fermentation. The products of hydrolysis confirmed by HPLC were cellobiose, glucose, xylose and mannose. The hydrolysate was fermented by S. cerevisiae, and concentrations of biomass, ethanol, and glucose were determined as a function of time. Results were compared to YGC modified medium (yeast extract, glucose and chloramphenicol) fermentation. Ethanol yield was 0.45 g g(-1), 88 % of the maximal theoretical value. Crysanthemum waste hydrolysate was suitable for ethanol production, containing glucose and mannose with adequate nutrients for S. cerevisiae fermentation and low fermentation inhibitor levels. PMID:23117675

Quevedo-Hidalgo, Balkys; Monsalve-Marín, Felipe; Narváez-Rincón, Paulo César; Pedroza-Rodríguez, Aura Marina; Velásquez-Lozano, Mario Enrique

2013-03-01

25

Identifying inhibitory compounds in lignocellulosic biomass hydrolysates using an exometabolomics approach  

PubMed Central

Background Inhibitors are formed that reduce the fermentation performance of fermenting yeast during the pretreatment process of lignocellulosic biomass. An exometabolomics approach was applied to systematically identify inhibitors in lignocellulosic biomass hydrolysates. Results We studied the composition and fermentability of 24 different biomass hydrolysates. To create diversity, the 24 hydrolysates were prepared from six different biomass types, namely sugar cane bagasse, corn stover, wheat straw, barley straw, willow wood chips and oak sawdust, and with four different pretreatment methods, i.e. dilute acid, mild alkaline, alkaline/peracetic acid and concentrated acid. Their composition and that of fermentation samples generated with these hydrolysates were analyzed with two GC-MS methods. Either ethyl acetate extraction or ethyl chloroformate derivatization was used before conducting GC-MS to prevent sugars are overloaded in the chromatograms, which obscure the detection of less abundant compounds. Using multivariate PLS-2CV and nPLS-2CV data analysis models, potential inhibitors were identified through establishing relationship between fermentability and composition of the hydrolysates. These identified compounds were tested for their effects on the growth of the model yeast, Saccharomyces. cerevisiae CEN.PK 113-7D, confirming that the majority of the identified compounds were indeed inhibitors. Conclusion Inhibitory compounds in lignocellulosic biomass hydrolysates were successfully identified using a non-targeted systematic approach: metabolomics. The identified inhibitors include both known ones, such as furfural, HMF and vanillin, and novel inhibitors, namely sorbic acid and phenylacetaldehyde. PMID:24655423

2014-01-01

26

Protein Hydrolysates as Hypoallergenic, Flavors and Palatants for Companion Animals  

NASA Astrophysics Data System (ADS)

Early civilizations have relied upon their good sense and experience to develop and improve their food quality. The discovery of soy sauce centuries ago can now be considered one of the earliest protein hydrolysates made by man to improve palatability of foods. Now, it is well known that such savory systems are not just sources for enjoyment but complex semiotic systems that direct the humans to satisfy the body's protein need for their sustenance. Recent developments have resulted in a wide range of cost effective savory flavorings, the best known of which are autolyzed yeast extracts and hydrolyzed vegetable proteins. New technologies have helped researchers to improve the savory characteristics of yeast extracts through the application of Maillard reaction and by generating specific flavor enhancers through the use of enzymes. An interesting parallel exists in the pet food industry, where a similar approach is taken in using animal protein hydrolysates to create palatability enhancers via Maillard reaction scheme. Protein hydrolysates are also utilized extensively as a source of nutrition to the elderly, young children and immuno-compromised patient population. These hydrolysates have an added advantage in having peptides small enough to avoid any chance of an allergenic reaction which sometimes occur with the consumption of larger sized peptides or proteins. Accordingly, protein hydrolysates are required to have an average molecular weight distribution in the range 800-1,500 Da to make them non-allergenic. The technical challenge for scientists involved in food and feed manufacture is to use an appropriate combination of enzymes within the existing economic constraints and other physical factors/limitations, such as heat, pH, and time, to create highly palatable, yet still nutritious and hypoallergenic food formulations.

Nagodawithana, Tilak W.; Nelles, Lynn; Trivedi, Nayan B.

27

Ethanol production from sugarcane bagasse hydrolysate using Pichia stipitis.  

PubMed

The objective of this study was to evaluate the ethanol production from the sugars contained in the sugarcane bagasse hemicellulosic hydrolysate with the yeast Pichia stipitis DSM 3651. The fermentations were carried out in 250-mL Erlenmeyers with 100 mL of medium incubated at 200 rpm and 30 degrees C for 120 h. The medium was composed by raw (non-detoxified) hydrolysate or by hydrolysates detoxified by pH alteration followed by active charcoal adsorption or by adsorption into ion-exchange resins, all of them supplemented with yeast extract (3 g/L), malt extract (3 g/L), and peptone (5 g/L). The initial concentration of cells was 3 g/L. According to the results, the detoxification procedures removed inhibitory compounds from the hemicellulosic hydrolysate and, thus, improved the bioconversion of the sugars into ethanol. The fermentation using the non-detoxified hydrolysate led to 4.9 g/L ethanol in 120 h, with a yield of 0.20 g/g and a productivity of 0.04 g L(-1) h(-1). The detoxification by pH alteration and active charcoal adsorption led to 6.1 g/L ethanol in 48 h, with a yield of 0.30 g/g and a productivity of 0.13 g L(-1) h(-1). The detoxification by adsorption into ion-exchange resins, in turn, provided 7.5 g/L ethanol in 48 h, with a yield of 0.30 g/g and a productivity of 0.16 g L(-1) h(-1). PMID:19802721

Canilha, Larissa; Carvalho, Walter; Felipe, Maria das Graças de Almeida; Silva, João Batista de Almeida e; Giulietti, Marco

2010-05-01

28

Fractionation of phenolic compounds extracted from propolis and their activity in the yeast Saccharomyces cerevisiae.  

PubMed

We have here investigated the activities of Slovenian propolis extracts in the yeast Saccharomyces cerevisiae, and identified the phenolic compounds that appear to contribute to these activities. We correlated changes in intracellular oxidation and cellular metabolic energy in these yeasts with the individual fractions of the propolis extracts obtained following solid-phase extraction. The most effective fraction was further investigated according to its phenolic compounds. PMID:23409133

Petelinc, Tanja; Polak, Tomaž; Demšar, Lea; Jamnik, Polona

2013-01-01

29

Fractionation of Phenolic Compounds Extracted from Propolis and Their Activity in the Yeast Saccharomyces cerevisiae  

PubMed Central

We have here investigated the activities of Slovenian propolis extracts in the yeast Saccharomyces cerevisiae, and identified the phenolic compounds that appear to contribute to these activities. We correlated changes in intracellular oxidation and cellular metabolic energy in these yeasts with the individual fractions of the propolis extracts obtained following solid-phase extraction. The most effective fraction was further investigated according to its phenolic compounds. PMID:23409133

Petelinc, Tanja; Polak, Tomaz; Demsar, Lea; Jamnik, Polona

2013-01-01

30

Production and rheological properties of a succinoglycan from Pseudomonas sp. 31260 grown on wood hydrolysates.  

PubMed

Pseudomonas sp. ATCC 31260 produced substantial amounts of anionic extracellular polysaccharide (EPS) from a mineral acid hydrolysate of wood, prepared using the "Tennessee Valley Authority" process. Partially purified EPS production approached 16.5 g/L (as hexadecyltrimethylammonium bromide precipitate) when the pH of the hydrolysate was initially adjusted to 7.5 and amended with 0.05% each of peptone and yeast extract. This EPS, now characterized as a succinoglycan, is composed of glucose, galactose, succinate, pyruvate, and acetate. Solutions of this EPS are pseudoplastic, and under specified conditions, are rheologically comparable with commercially available xanthan. PMID:8542556

Meade, M J; Tanenbaum, S W; Nakas, J P

1995-12-01

31

Strategy for the extraction of yeast DNA from artisan agave must for quantitative PCR analysis.  

PubMed

An efficient method for the direct extraction of yeast genomic DNA from agave must was developed. The optimized protocol, which was based on silica-adsorption of DNA on microcolumns, included an enzymatic cell wall degradation step followed by prolonged lysis with hot detergent. The resulting extracts were suitable templates for subsequent qPCR assays that quantified mixed yeast populations in artisan Mexican mezcal fermentations. PMID:21820955

Kirchmayr, Manuel Reinhart; Segura-Garcia, Luis Eduardo; Flores-Berrios, Ericka Patricia; Gschaedler, Anne

2011-11-01

32

Effect of yeast extract on Escherichia coli growth and acetic acid production  

Microsoft Academic Search

Fed batch cultures were performed to investigate the effect of yeast extract concentration on the kinetics of growth and acetic acid production of recombinant Escherichia coli BL21 in a synthetic medium. Three runs were performed with 40g\\/l total glucose concentration. The yeast extract\\/glucose ratio (YE\\/G; w\\/w), was 0.1, 0.05 and 0.025 in the feed. These decreasing YE\\/G values did not

D. C. Suárez; C. W. Liria; B. V. Kilikian

1998-01-01

33

Selection of yeasts for single cell protein production on media based on Jerusalem artichoke extracts.  

PubMed

Several yeast strains can grow with good yield (0.16 to 0.19 mg protein/mg carbohydrate) on nitrogen supplemented Jerusalem artichoke extract. The most promising strain is Lipomyces starkeyi. Including by-products (pulps, proteins of extract), protein production can reach 2 metric tons/ha. PMID:6613165

Apaire, V; Guiraud, J P; Galzy, P

1983-01-01

34

Kefir-yeast technology: Industrial scale-up of alcoholic fermentation of whey, promoted by raisin extracts, using kefir-yeast granular biomass  

Microsoft Academic Search

Industrial scale-up of whey fermentation, promoted by raisin extracts, using free kefir-yeast cells is reported. The fermented whey would be exploited as raw material to produce kefir-like whey-based drinks, potable and fuel alcohol, as well as kefir-yeast biomass for use as baker's yeast. The scale-up process involved the development of a technology transfer scheme from lab-scale experiments to a successive

Athanasios A. Koutinas; Ilias Athanasiadis; Argyro Bekatorou; Costas Psarianos; Maria Kanellaki; Nikolaos Agouridis; Georgios Blekas

2007-01-01

35

Fermentation of cellulosic hydrolysates obtained by enzymatic saccharification of sugarcane bagasse pretreated by hydrothermal processing  

Microsoft Academic Search

This work aims to evaluate the fermentability of cellulosic hydrolysates obtained by enzymatic saccharification of sugarcane\\u000a bagasse pretreated by hydrothermal processing using Candida guilliermondii FTI 20037 yeast. The inoculum was obtained from yeast culture in a medium containing glucose as a carbon source supplemented\\u000a with rice bran extract, CaCl2·2H2O and (NH4)2SO4 in 50 mL Erlenmeyer flasks, containing 20 mL of medium, initial

Vinícius F. N. Silva; Priscila V. Arruda; Maria G. A. Felipe; Adilson R. Gonçalves; George J. M. Rocha

2011-01-01

36

Separation of astaxanthin from red yeast Phaffia rhodozyma by supercritical carbon dioxide extraction  

Microsoft Academic Search

The supercritical fluid extraction (SFE) behavior was investigated to extract astaxanthin from the red yeast Phaffia rhodozyma, which was disrupted and dried by bead mill and spray dryer, respectively. The effects of extraction pressure (102–500bar), temperature (40, 60 and 80°C), CO2 flow rate (superficial velocities of 0.27 and 0.54cm\\/min) and the use of ethyl alcohol as a modifier (1, 5,

Gio-Bin Lim; Sang-Yun Lee; Eun-Kyu Lee; Seung-Joo Haam; Woo-Sik Kim

2002-01-01

37

Continuous ethanol production by immobilized yeast cells and ethanol recovery by liquid-liquid extraction  

SciTech Connect

Contributions on ethanol fermentation by immobilized yeast cells and ethanol-water separation by liquid-liquid extraction are presented. The characterization of a packed-bed fermentor with yeast immobilized in carrageenan gel beads as well as its main operational features are reported, giving special emphasis to cell growth inside the beads during continuous fermentation experiments. A new separation process for dilute ethanol-water mixtures based on a solvent extraction step is proposed. The process development and solvent selection have been carried out. Although the first results are promising, the energy costs of the process are still too high.

Sola, C.; Casas, C.; Godia, F.; Poch, M.; Serra, A.; Scott, C.D. (ed.)

1986-01-01

38

Biphenyl synthase from yeast-extract-treated cell cultures of Sorbus aucuparia  

Microsoft Academic Search

Biphenyls and dibenzofurans are the phytoalexins of the Maloideae, a subfamily of the economically important Rosaceae. The biphenyl aucuparin accumulated in Sorbus aucuparia L. cell cultures in response to yeast extract treatment. Incubation of cell-free extracts from challenged cell cultures with benzoyl-CoA and malonyl-CoA led to the formation of 3,5-dihydroxybiphenyl. This reaction was catalysed by a novel polyketide synthase, which

Benye Liu; Till Beuerle; Tim Klundt; Ludger Beerhues

2004-01-01

39

Complex coacervation of collagen hydrolysate extracted from leather solid wastes and chitosan for controlled release of lavender oil.  

PubMed

In the world, approximately 600,000 metric tonnes of chromium-containing solid wastes are generated by the leather industry each year. Environmental concerns and escalating landfill costs are becoming increasingly serious problems to the leather industry and seeking solutions to these problems is a prime concern in much research today. In this study, solid collagen-based protein hydrolysate was isolated from chromium-tanned leather wastes and its chemical properties were determined. Microcapsules of collagen hydrolysate (CH) - chitosan (C) crosslinked with glutaraldehyde (GA) containing Lavender oil (LO) were prepared by complex coacervation method. The effects of various processing parameters, including the CH to C ratio, LO content, and GA, on the oil load (%), oil content (%), encapsulation efficiency (%) and release rate of LO from microcapsules were investigated. As the ratio of C present in the CH/C mixture and crosslinking density increased, the release rate of LO from microcapsules slowed down. Optical and scanning electron microscopy images illustrated that the LO microcapsules were spherical in shape. Fourier transform infrared spectroscopy (FTIR) studies confirmed that there was no significant interaction between CH/C complex and LO. PMID:22361107

Ocak, Bu?ra

2012-06-15

40

Treatment of rice straw hemicellulosic hydrolysates with advanced oxidative processes: a new and promising detoxification method to improve the bioconversion process  

PubMed Central

Background The use of lignocellulosic constituents in biotechnological processes requires a selective separation of the main fractions (cellulose, hemicellulose and lignin). During diluted acid hydrolysis for hemicellulose extraction, several toxic compounds are formed by the degradation of sugars and lignin, which have ability to inhibit microbial metabolism. Thus, the use of a detoxification step represents an important aspect to be considered for the improvement of fermentation processes from hydrolysates. In this paper, we evaluated the application of Advanced Oxidative Processes (AOPs) for the detoxification of rice straw hemicellulosic hydrolysate with the goal of improving ethanol bioproduction by Pichia stipitis yeast. Aiming to reduce the toxicity of the hemicellulosic hydrolysate, different treatment conditions were analyzed. The treatments were carried out according to a Taguchi L16 orthogonal array to evaluate the influence of Fe+2, H2O2, UV, O3 and pH on the concentration of aromatic compounds and the fermentative process. Results The results showed that the AOPs were able to remove aromatic compounds (furan and phenolic compounds derived from lignin) without affecting the sugar concentration in the hydrolysate. Ozonation in alkaline medium (pH 8) in the presence of H2O2 (treatment A3) or UV radiation (treatment A5) were the most effective for hydrolysate detoxification and had a positive effect on increasing the yeast fermentability of rice straw hemicellulose hydrolysate. Under these conditions, the higher removal of total phenols (above 40%), low molecular weight phenolic compounds (above 95%) and furans (above 52%) were observed. In addition, the ethanol volumetric productivity by P. stipitis was increased in approximately twice in relation the untreated hydrolysate. Conclusion These results demonstrate that AOPs are a promising methods to reduce toxicity and improve the fermentability of lignocellulosic hydrolysates. PMID:23414668

2013-01-01

41

Ethanol production by a new pentose-fermenting yeast strain, Scheffersomyces stipitis UFMG-IMH 43.2, isolated from the Brazilian forest.  

PubMed

The ability of a recently isolated Scheffersomyces stipitis strain (UFMG-IMH 43.2) to produce ethanol from xylose was evaluated. For the assays, a hemicellulosic hydrolysate produced by dilute acid hydrolysis of sugarcane bagasse was used as the fermentation medium. Initially, the necessity of adding nutrients (MgSO(4)·7H(2)O, yeast extract and/or urea) to this medium was verified, and the yeast extract supplementation favoured ethanol production by the yeast. Then, in a second stage, assays under different initial xylose and cell concentrations, supplemented or not with yeast extract, were performed. All these three variables showed significant (p < 0.05) influence on ethanol production. The best results (ethanol yield and productivity of 0.19 g/g and 0.13 g/l/h, respectively) were obtained using the hydrolysate containing an initial xylose concentration of 30 g/l, supplemented with 5.0 g/l yeast extract and inoculated with an initial cell concentration of 2.0 g/l. S. stipitis UFMG-IMH 43.2 was demonstrated to be a yeast strain with potential for use in xylose conversion to ethanol. The establishment of the best fermentation conditions was also proved to be of great importance to increasing the product formation by this yeast strain. These findings open up new perspectives for the establishment of a feasible technology for ethanol production from hemicellulosic hydrolysates. PMID:21626536

Ferreira, Adriana D; Mussatto, Solange I; Cadete, Raquel M; Rosa, Carlos A; Silva, Silvio S

2011-07-01

42

Acceleration of yoghurt fermentation time by yeast extract and partial characterisation of the active components.  

PubMed

Water soluble autolysate of yeast, usually utilised for microbial growth support, was used as additive in yoghurt fermentation. The yeast extract (YE) resulted in a decrease of fermentation time by 21% to reach a pH of 4·6. However, the YE resulted in unacceptable flavour and taste. By size exclusion chromatography, a fraction of the YE was obtained that could account for the observed 21% decrease in fermentation time. The fraction contained molecules of low molecular weight, consisting of minerals, free amino acids and peptides. The acceleration of the yoghurt fermentation was ascribed to the short peptides in the fraction. It is proposed that the application of this extract in industrial yoghurt manufacture would result in savings for both the industry and the consumer. PMID:25353311

Smith, Esti-Andrine; Myburgh, Jacobus; Osthoff, Gernot; de Wit, Maryna

2014-11-01

43

Sequential extraction leading to improved proteomic analysis of the oleaginous yeast Lipomyces starkeyi.  

PubMed

The oleaginous yeast Lipomyces starkeyi (L. starkeyi) is an excellent intracellular lipid producer. Thus, extraction of protein from lipid-rich L. starkeyi samples following conventional methods can be difficult, leading to poor data in terms of proteomic analysis. The presence of lipophilic components in those samples may also interfere with the extraction process and the downstream analysis. In this work, we developed a sequential extraction method for preparation and analysis of L. starkeyi proteome combining to an online multidimensional nano reversed-phase liquid chromatography-tandem mass spectrometry (microRPLC-MS/MS) strategy. Protein hits of high confidence reached 227 with false positive rate less than 0.1, twice of those identified from the one-buffer extraction preparation. Moreover, the protein hits related to primary metabolism was increased, which may be important to establish the molecular mechanism of lipid accumulation. The method should be valuable for protein extraction from oleaginous species. PMID:21847969

Liu, Hongwei; Zhao, Xin; Cheng, Kai; Zhao, Zongbao; Ye, Mingliang

2011-05-01

44

Induction of rosmarinic acid biosynthesis in Lithospermum erythrorhizon cell suspension cultures by yeast extract  

Microsoft Academic Search

A transient increase in rosmarinic acid (RA) content in cultured cells of Lithospermum erythrorhizon was observed after addition of yeast extract (YE) to the suspension cultures, reaching a maximum at 24 hr. The highest increase of the RA content (2.5-fold) was obtained when 6-day-old cells in the exponential growth phase were treated with YE. Preceding the induced RA accumulation, phenylalanine

Hajime Mizukami; Terumi Ogawa; Hiromu Ohashi; Brian E. Ellis

1992-01-01

45

Aniline blue-containing buffered charcoal-yeast extract medium for presumptive identification of Legionella species  

SciTech Connect

By utilizing buffered charcoal-yeast extract medium containing 0.01% aniline blue in conjunction with a long-wave UV light, the differentiation of five species of Legionella was facilitated. L. pneumophila, when grown on this medium, did not absorb the aniline blue dye; however, L. micdadei, L. dumoffii, L. bozemanii, and L. gormanii absorbed the dye in varying amounts and produced colonies of various shades of blue.

Holmes, R.L.

1982-04-01

46

Effects of yeast extract and glucose on xanthan production and cell growth in batch culture of Xanthomonas campestris  

Microsoft Academic Search

Although available kinetic data provide a useful insight into the effects of medium composition on xanthan production by\\u000a Xanthomonas campestris, they cannot account for the synergetic effects of carbon (glucose) and nitrogen (yeast extract) substrates on cell growth\\u000a and xanthan production. In this work, we studied the effects of the glucose\\/yeast-extract ratio (G\\/YE) in the medium on cell\\u000a growth and

Yang-Ming Lo; Shang-Tian Yang; David B. Min

1997-01-01

47

Utilization of (15)N-labelled yeast hydrolysate in Lactococcus lactis IL1403 culture indicates co-consumption of peptide-bound and free amino acids with simultaneous efflux of free amino acids.  

PubMed

Lactococcus lactis subsp. lactis IL1403 was grown in medium containing unlabelled free amino acids and (15)N-labelled yeast hydrolysate to gain insight into the role of peptides as a source of amino acids under conditions where free amino acids are abundant. A mathematical model was composed to estimate the fluxes of free and peptide-derived amino acids into and out of the intracellular amino acid pool. We observed co-consumption of peptides and free amino acids and a considerable efflux of most free amino acids during growth. We did not observe significant differences between the peptide consumption patterns of essential and non-essential amino acids, which suggests that the incorporation of a particular amino acid is more dependent on its availability in a readily assimilated form than the organism's auxotrophy for it. For most amino acids the contribution of peptide-bound forms to the formation of biomass was initially between 30 and 60 % with the remainder originating from free amino acids. During the later stages of fermentation we observed a decrease in the utilization of peptide-bound amino acids, thus indicating that the more readily assimilated peptides are gradually exhausted from the medium during growth. PMID:24389760

Kevvai, Kaspar; Kütt, Mary-Liis; Nisamedtinov, Ildar; Paalme, Toomas

2014-03-01

48

Efficient fermentation of Pinus sp. acid hydrolysates by an ethanologenic strain of Escherichia coli.  

PubMed Central

Process conditions for the acid hydrolysis of pine hemicellulose and cellulose have been described which provide a biocompatible sugar solution. By using an improved strain of recombinant Escherichia coli, strain KO11, hydrolysates supplemented with yeast extract and tryptone nutrients were converted to ethanol with an efficiency of 85% to over 100% on the basis of monomer sugar content (approximately 72 g/liter) and with the production of 35 g of ethanol per liter in 48 h. In the process described, approximately 347 liters of ethanol could be produced per dry metric ton of lignocellulose. PMID:1599258

Barbosa, M F; Beck, M J; Fein, J E; Potts, D; Ingram, L O

1992-01-01

49

Effects of Temperature and Substrate Concentration on Lipid Production by Chlorella vulgaris from Enzymatic Hydrolysates of Lipid-Extracted Microalgal Biomass Residues (LMBRs).  

PubMed

The enzymatic hydrolysates of the lipid-extracted microalgal biomass residues (LMBRs) from biodiesel production were evaluated as nutritional sources for the mixotrophic growth of Chlorella vulgaris and lipid production at different temperature levels and substrate concentrations. Both parameters had a significant effect on cell growth and lipid production. It was observed that C. vulgaris could grow mixotrophically in a wide range of temperatures (20?35 °C). The optimal temperature for cell growth and lipid accumulation of the mixotrophic growth of C. vulgaris was between 25 and 30 °C. The neutral lipids of the culture at 25 °C accounted for as much as 82 % of the total lipid content in the microalga at culture day 8. Fatty acid composition analysis showed that the increase of saturated fatty acids was proportional to the increase in temperature. The maximum biomass concentration of 4.83 g/L and the maximum lipid productivity of 164 mg/L/day were obtained at an initial total sugar concentration of 10 g/L and an initial total concentration of amino acids of 1.0 g/L but decreased at lower and higher substrate concentrations. The present results show that LMBRS could be utilized by the mixotrophic growth of C. vulgaris for microalgal lipid production under the optimum temperature and substrate concentration. PMID:25138600

Ma, Xiaochen; Zheng, Hongli; Huang, He; Liu, Yuhuan; Ruan, Roger

2014-10-01

50

Norovirus capsid protein expressed in yeast forms virus-like particles and stimulates systemic and mucosal immunity in mice following an oral administration of raw yeast extracts.  

PubMed

Norovirus (NV) gastroenteritis is a widespread disease affecting people of all ages worldwide. A simple, safe, and easily deliverable vaccine may be the key for the control and prevention of NV gastroenteritis. In this study, we demonstrated that a NV recombinant capsid protein (strain VA387, genogroup II.4) expressed in yeast (Pichia pastoris) spontaneously formed virus-like particles (VLPs) like those expressed in other in vitro systems. Oral administration of raw material from the yeast cell lysates containing 0.1 mg of VLPs without an adjuvant resulted in systemic and mucosal immune responses in mice. Significantly higher and earlier responses were observed in mice receiving a higher dose (1 mg per dose) of the antigen. Both the serum and fecal antibodies blocked VA387 VLP binding to its histo-blood group antigen receptors. The animals did not reveal any side effect following the administration of the yeast lysates. Our results indicated that yeast is a simple, effective alternative for NV VLP production. The mice immunization study also indicated that the oral administration of raw yeast extracts without an adjuvant is a safe and simple way which is worth to be studied for vaccine delivery in humans. PMID:17133551

Xia, Ming; Farkas, Tibor; Jiang, Xi

2007-01-01

51

Biphenyl synthase from yeast-extract-treated cell cultures of Sorbus aucuparia.  

PubMed

Biphenyls and dibenzofurans are the phytoalexins of the Maloideae, a subfamily of the economically important Rosaceae. The biphenyl aucuparin accumulated in Sorbus aucuparia L. cell cultures in response to yeast extract treatment. Incubation of cell-free extracts from challenged cell cultures with benzoyl-CoA and malonyl-CoA led to the formation of 3,5-dihydroxybiphenyl. This reaction was catalysed by a novel polyketide synthase, which will be named biphenyl synthase. The most efficient starter substrate for the enzyme was benzoyl-CoA. Relatively high activity was also observed with 2-hydroxybenzoyl-CoA but, instead of the corresponding biphenyl, the derailment product 2-hydroxybenzoyltriacetic acid lactone was formed. PMID:14595561

Liu, Benye; Beuerle, Till; Klundt, Tim; Beerhues, Ludger

2004-01-01

52

Recovery of spores of Clostridium botulinum in yeast extract agar and pork infusion agar after heat treatment.  

PubMed Central

Yeast extract agar, pork infusion agar, and modifications of these media were used to recover heated Clostridium botulinum spores. The D- and z-values were determined. Two type A strains and one type B strain of C. botulinum were studied. In all cases the D-values were largest when the spores were recovered in yeast extract agar, compared to the D-values for spores recovered in pork infusion agar. The z-values for strains 62A and A16037 were largest when the spores were recovered in pork infusion agar. The addition of sodium bicarbonate and sodium thioglycolate to pork infusion agar resulted in D-values for C. botulinum 62A spores similar to those for the same spores recovered in yeast extract agar. The results suggest that sodium bicarbonate and sodium thioglycolate should be added to recovery media for heated C. botulinum spores to obtain maximum plate counts. PMID:335970

Odlaug, T E; Pflug, I J

1977-01-01

53

Novel isolates for biological detoxification of lignocellulosic hydrolysate.  

PubMed

In this paper, two new strians, Issatchenkia occidentalis (Lj-3, CCTCC M 2006097) and Issatchenkia orienalis (S-7, CCTCC M 2006098), isolated from different environments on solid media, were used in the detoxification process of the hemicellulosic hydrolysate of sugarcane bagasse. High-pressure liquid chromatography elution curve of UV-absorption compounds represented by acetic acid, furfural, and guaiacol (toxic compounds found in the hemicellulosic hydrolysate) showed that several chromatographic peaks were evidently diminished for the case of detoxified hydrolysate with isolate strains compared to the high peaks resulted for no detoxified hydrolysate. It was clear that these inhibitors were degraded by the two new isolates during their cultivation process. Fermentation results for the biodetoxified hydrolysate showed an increase in xylitol productivity (Q (p)) by 1.97 and 1.95 times (2.03 and 2.01 g l(-1) h(-1)) and in xylitol yield (Y (p)) by 1.72 and 1.65 times (0.93 and 0.89 g xylitol per gram xylose) for hydrolysate treated with S-7 and Lj-3, respectively, in comparison with no detoxified hydrolysate (1.03 g l(-1) h(-1) and 0.54 g xylitol per gram xylose). This present work demonstrated the importance of Issatchenkia yeast in providing an effective biological detoxification approach to remove inhibitors and improve hydrolysate fermentability, leading to a high xylitol productivity and yield. PMID:18649037

Hou-Rui, Zhang; Xiang-Xiang, Qin; Silva, Silvio S; Sarrouh, Boutros F; Ai-Hua, Cai; Yu-Heng, Zhou; Ke, Jin; Qiu, Xiang

2009-02-01

54

Modification of collagen hydrolysates  

Microsoft Academic Search

Collagen hydrolysates prepared by alkaline and enzymatic hydrolysis of chrome leather waste were characterized and their condensates with long-chain carboxylic acids and their chlorides were synthesised. The syntheses were carried out under atmospheric pressure; in some cases a catalyst was used. The collagen hydrolysate and its condensate with oleic acid were grafted with ethylene- and propylene oxide, respectively. The extent

V. Šemrl-Kosma?; A. Gantar

1995-01-01

55

The effect of yeast extract supplementation on the production of lactic acid from whey permeate by Lactobacillus helueticus  

Microsoft Academic Search

Batch and continuous two-stage cultures have been conducted in order to determine the effect of yeast extract (YE) on the homolactic fermentation of whey permeate byLactobacillus helveticus. Supplementation with YE had a significant effet on lactic acid concentration, volumetric productivity, and substrate conversion, but not on lactic acid yield. Volumetric productivity in the first stage increased from 2 to 9

A. Aeschlimann; U. von Stockar

1990-01-01

56

In Vivo Hypocholesterolemic Effect of MARDI Fermented Red Yeast Rice Water Extract in High Cholesterol Diet Fed Mice  

PubMed Central

Fermented red yeast rice has been traditionally consumed as medication in Asian cuisine. This study aimed to determine the in vivo hypocholesterolemic and antioxidant effects of fermented red yeast rice water extract produced using Malaysian Agricultural Research and Development Institute (MARDI) Monascus purpureus strains in mice fed with high cholesterol diet. Absence of monacolin-k, lower level of ?-aminobutyric acid (GABA), higher content of total amino acids, and antioxidant activities were detected in MARDI fermented red yeast rice water extract (MFRYR). In vivo MFRYR treatment on hypercholesterolemic mice recorded similar lipid lowering effect as commercial red yeast rice extract (CRYR) as it helps to reduce the elevated serum liver enzyme and increased the antioxidant levels in liver. This effect was also associated with the upregulation of apolipoproteins-E and inhibition of Von Willebrand factor expression. In summary, MFRYR enriched in antioxidant and amino acid without monacolin-k showed similar hypocholesterolemic effect as CRYR that was rich in monacolin-k and GABA. PMID:25031606

Beh, Boon Kee; Kong, Joan; Ho, Wan Yong; Mohd Yusof, Hamidah; Hussin, Aminuddin bin; Jaganath, Indu Bala; Alitheen, Noorjahan Banu; Jamaluddin, Anisah

2014-01-01

57

Extraction of nucleic acids from yeast cells and plant tissues using ethanol as medium for sample preservation and cell disruption.  

PubMed

Here we report that dehydrated ethanol is an excellent medium for both in situ preservation of nucleic acids and cell disruption of plant and yeast cells. Cell disruption was strongly facilitated by prior dehydration of the ethanol using dehydrated zeolite. Following removal of ethanol, nucleic acids were extracted from the homogenate pellet using denaturing buffers. The method provided DNA and RNA of high yield and integrity. Whereas cell wall disruption was essential for extraction of DNA and large RNA molecules, smaller molecules such as tRNAs could be selectively extracted from undisrupted, ethanol-treated yeast cells. Our results demonstrate the utility of absolute ethanol for sample fixation, cell membrane and cell wall disruption, as well as preservation of nucleic acids during sample storage. PMID:20854267

Linke, Bettina; Schröder, Kersten; Arter, Juliane; Gasperazzo, Tatiana; Woehlecke, Holger; Ehwald, Rudolf

2010-09-01

58

Coupled RNA polymerase II transcription and 3? end formation with yeast whole-cell extracts  

PubMed Central

RNA polymerase II (RNAP II) transcription and pre-mRNA 3? end formation are linked through physical and functional interactions. We describe here a highly efficient yeast in vitro system that reproduces both transcription and 3? end formation in a single reaction. The system is based on simple whole-cell extracts that were supplemented with a hybrid Gal4-VP16 transcriptional activator and supercoiled plasmid DNA templates encoding G-less cassette reporters. We found that the coupling of transcription and processing in vitro enhanced pre-mRNA 3? end formation and reproduced requirements for poly(A) signals and polyadenylation factors. Unexpectedly, however, we show that in vitro transcripts lacked m7G-caps. Reconstitution experiments with CF IA factor assembled entirely from heterologous components suggested that the CTD interaction domain of the Pcf11 subunit was required for proper RNAP II termination but not 3? end formation. Moreover, we observed reduced termination activity associated with extracts prepared from cells carrying a mutation in the 5?-3? exonuclease Rat1 or following chemical inhibition of exonuclease activity. Thus, in vitro transcription coupled to pre-mRNA processing recapitulates hallmarks of poly(A)-dependent RNAP II termination. The in vitro transcription/processing system presented here should provide a useful tool to further define the role of factors involved in coupling. PMID:20810619

Mariconti, Luisa; Loll, Bernhard; Schlinkmann, Karola; Wengi, Agnieszka; Meinhart, Anton; Dichtl, Bernhard

2010-01-01

59

Coupled RNA polymerase II transcription and 3' end formation with yeast whole-cell extracts.  

PubMed

RNA polymerase II (RNAP II) transcription and pre-mRNA 3' end formation are linked through physical and functional interactions. We describe here a highly efficient yeast in vitro system that reproduces both transcription and 3' end formation in a single reaction. The system is based on simple whole-cell extracts that were supplemented with a hybrid Gal4-VP16 transcriptional activator and supercoiled plasmid DNA templates encoding G-less cassette reporters. We found that the coupling of transcription and processing in vitro enhanced pre-mRNA 3' end formation and reproduced requirements for poly(A) signals and polyadenylation factors. Unexpectedly, however, we show that in vitro transcripts lacked m?G-caps. Reconstitution experiments with CF IA factor assembled entirely from heterologous components suggested that the CTD interaction domain of the Pcf11 subunit was required for proper RNAP II termination but not 3' end formation. Moreover, we observed reduced termination activity associated with extracts prepared from cells carrying a mutation in the 5'-3' exonuclease Rat1 or following chemical inhibition of exonuclease activity. Thus, in vitro transcription coupled to pre-mRNA processing recapitulates hallmarks of poly(A)-dependent RNAP II termination. The in vitro transcription/processing system presented here should provide a useful tool to further define the role of factors involved in coupling. PMID:20810619

Mariconti, Luisa; Loll, Bernhard; Schlinkmann, Karola; Wengi, Agnieszka; Meinhart, Anton; Dichtl, Bernhard

2010-11-01

60

Development of a D-xylose fermenting and inhibitor tolerant industrial Saccharomyces cerevisiae strain with high performance in lignocellulose hydrolysates using metabolic and evolutionary engineering  

PubMed Central

Background The production of bioethanol from lignocellulose hydrolysates requires a robust, D-xylose-fermenting and inhibitor-tolerant microorganism as catalyst. The purpose of the present work was to develop such a strain from a prime industrial yeast strain, Ethanol Red, used for bioethanol production. Results An expression cassette containing 13 genes including Clostridium phytofermentans XylA, encoding D-xylose isomerase (XI), and enzymes of the pentose phosphate pathway was inserted in two copies in the genome of Ethanol Red. Subsequent EMS mutagenesis, genome shuffling and selection in D-xylose-enriched lignocellulose hydrolysate, followed by multiple rounds of evolutionary engineering in complex medium with D-xylose, gradually established efficient D-xylose fermentation. The best-performing strain, GS1.11-26, showed a maximum specific D-xylose consumption rate of 1.1 g/g DW/h in synthetic medium, with complete attenuation of 35 g/L D-xylose in about 17 h. In separate hydrolysis and fermentation of lignocellulose hydrolysates of Arundo donax (giant reed), spruce and a wheat straw/hay mixture, the maximum specific D-xylose consumption rate was 0.36, 0.23 and 1.1 g/g DW inoculum/h, and the final ethanol titer was 4.2, 3.9 and 5.8% (v/v), respectively. In simultaneous saccharification and fermentation of Arundo hydrolysate, GS1.11-26 produced 32% more ethanol than the parent strain Ethanol Red, due to efficient D-xylose utilization. The high D-xylose fermentation capacity was stable after extended growth in glucose. Cell extracts of strain GS1.11-26 displayed 17-fold higher XI activity compared to the parent strain, but overexpression of XI alone was not enough to establish D-xylose fermentation. The high D-xylose consumption rate was due to synergistic interaction between the high XI activity and one or more mutations in the genome. The GS1.11-26 had a partial respiratory defect causing a reduced aerobic growth rate. Conclusions An industrial yeast strain for bioethanol production with lignocellulose hydrolysates has been developed in the genetic background of a strain widely used for commercial bioethanol production. The strain uses glucose and D-xylose with high consumption rates and partial cofermentation in various lignocellulose hydrolysates with very high ethanol yield. The GS1.11-26 strain shows highly promising potential for further development of an all-round robust yeast strain for efficient fermentation of various lignocellulose hydrolysates. PMID:23800147

2013-01-01

61

[Mechanism exploration on synthesis of secondary metabolites in Sorbus aucuparia cell cultures treated with yeast extract].  

PubMed

Suspension cultures cell of Sorbus aucuparia (SASC) was used as materials, the changes of physiological and biochemical indexes of SASC after treatment with yeast extract (YE) were detected, and the synthetic mechanism of secondary metabolites in SASC treated with YE was preliminarily explored. The results were as follows: under the assay conditions, SASC was induced to synthesize five biphenyl compounds, and these compounds content changed differently with induction time prolonging; YE treatment inhibited cell growth, the culture medium pH was gradually reduced after treatment; water-soluble protein content showed a trend of slow decline, which was significantly increased in YE treatment group (YE group) compared with the control group (CK group), the maximum relative content was 147.76% in contrast with CK group; both YE group and CK group were extracellular Ca2+ flow influx, but the YE group flow was significantly slow than CK group. The results indicate that YE induced the cells in a stress state, which was not conducive to the growth of cells and forced the cells to synthesize biphenyl compounds against external stress; water-soluble protein may serve as intracellular enzymes involved in the synthesis of compounds regulation; Ca2+ may as signal molecule mediate cell signal transduction respond to YE stress. PMID:25272834

Huang, Lei; Xiao, Wen-Juan; Yang, Guang; Mo, Ge; Lin, Shu-Fang; Wu, Zhi-Gang; Guo, Lan-Ping

2014-06-01

62

Antiatherosclerotic efficacy of policosanol, red yeast rice extract and astaxanthin in the rabbit.  

PubMed

The effects of policosanol (P), of extract of red yeast rice (rice fermented with Monascus purpureus) (RYE) and of astaxanthin (A) (constituents of Armolipid) were investigated in a model of experimental atherosclerosis provoked in the rabbit by atherogenic cholesterol-enriched feed (ACEF). P and RYE and their combination were able to lower the increase of serum total cholesterol and of LDL cholesterol elicited by 3-month feeding with ACEF. They also were able to reduce the increase of blood malondialdehyde (MDA), a tracer of lipid peroxidation by the free radicals released by ACEF. When combined, the substances developed either additive or potentiated effects, supporting the rationale of their combination. Remarkable was the protective effect on lipid infiltration in the aortic wall provoked by ACEF, which was reduced by P and by RYE and almost completely prevented by the addition of A to the P-RYE combination. The results support the rationale of a combination of P, RYE and A as a useful food supplement in hyperlipemic patients. PMID:16032970

Setnikar, Ivo; Senin, Paolo; Rovati, Lucio C

2005-01-01

63

Evaluation of the yeast-extract signaling pathway leading to silymarin biosynthesis in milk thistle hairy root culture  

Microsoft Academic Search

The biosynthesis of silymarin, a potent antihepatotoxic compound, from the dried fruits of Silybum marianum L. Gaertn in hairy root cultures can be stimulated by a yeast extract elicitor. These results correlated with culture time,\\u000a and the biosynthesis reached a maximum of 0.47 mg g?1 DW by 72 h after culture (2-fold higher than the control). Lipoxygenase activity and linoleic acid content were

Tahereh Hasanloo; Roshanak Sepehrifar; Hassan Rahnama; Mohammad Reza Shams

2009-01-01

64

Cell-recycle continuous fermentation of Enterococcus faecalis RKY1 for economical production of lactic acid by reduction of yeast extract supplementation.  

PubMed

Both lactic acid productivity and cell growth were linearly correlated with yeast extract supplementation in batch fermentation. During conventional continuous operation, although fresh feed was introduced into the bioreactor with a significantly low dilution rate (0.04 h(-1)), the amount of yeast extract employed was not enough to maintain the growth of microorganism. However, when the fresh feed contained 100 g/l glucose and 2 g/l yeast extract during cell-recycle continuous operation at a dilution rate of 0.04 h(-1), more than 90 g/l lactic acid was continuously produced, with the average productivity of 3.72 g/l·h. In this experiment, 82 g of yeast extract (77% of reduction yield) could be reduced for the production of 1 kg of lactic acid compared with batch fermentation of a similar volumetric productivity. PMID:24561722

Lee, Ryun-Kyung; Ryu, Hwa-Won; Oh, Hurok; Kim, Mina; Wee, Young-Jung

2014-05-01

65

Peat Hydrolysate Medium Optimization for Pullulan Production  

PubMed Central

Peat hydrolysate, a diluted acid-autoclaved extract of peat, was used as a substrate for the production of the extracellular polysaccharide pullulan by three strains of Aureobasidium pullulans, 140B, 142, and 2552. It was found that the addition of (NH4)2SO4 and K2HPO4 as sources of nitrogen and phosphate, respectively, is not necessary for the polysaccharide production. The economically optimized culture medium for large-scale production of pullulan contains peat hydrolysate, 0.05% NaCl, 0.02% MgSO4, and 0.01% antifoam FG-10. The initial pH of peat hydrolysate medium is adjusted to its optimum value of 6.0 with Ca(OH)2. The total ingredient cost for the production of each kilogram of pullulan with optimized medium is only 1/10 of that with the nonoptimized medium. In this study, a zero cost for peat hydrolysate was assumed, since it is an effluent of the peat and peat processing industries. PMID:16346596

Boa, Jacques M.; LeDuy, Anh

1984-01-01

66

21 CFR 102.22 - Protein hydrolysates.  

...the ingredient and shall include the identity of the food source from which the protein was derived. (a) “Hydrolyzed wheat gluten,” “hydrolyzed soy protein,” and “autolyzed yeast extract” are examples of acceptable names. “Hydrolyzed...

2014-04-01

67

21 CFR 102.22 - Protein hydrolysates.  

Code of Federal Regulations, 2012 CFR

...the ingredient and shall include the identity of the food source from which the protein was derived. (a) “Hydrolyzed wheat gluten,” “hydrolyzed soy protein,” and “autolyzed yeast extract” are examples of acceptable names. “Hydrolyzed...

2012-04-01

68

21 CFR 102.22 - Protein hydrolysates.  

Code of Federal Regulations, 2010 CFR

...the ingredient and shall include the identity of the food source from which the protein was derived. (a) “Hydrolyzed wheat gluten,” “hydrolyzed soy protein,” and “autolyzed yeast extract” are examples of acceptable names. “Hydrolyzed...

2010-04-01

69

21 CFR 102.22 - Protein hydrolysates.  

Code of Federal Regulations, 2013 CFR

...the ingredient and shall include the identity of the food source from which the protein was derived. (a) “Hydrolyzed wheat gluten,” “hydrolyzed soy protein,” and “autolyzed yeast extract” are examples of acceptable names. “Hydrolyzed...

2013-04-01

70

21 CFR 102.22 - Protein hydrolysates.  

Code of Federal Regulations, 2011 CFR

...the ingredient and shall include the identity of the food source from which the protein was derived. (a) “Hydrolyzed wheat gluten,” “hydrolyzed soy protein,” and “autolyzed yeast extract” are examples of acceptable names. “Hydrolyzed...

2011-04-01

71

Xylitol production from corn fiber and sugarcane bagasse hydrolysates by Candida tropicalis.  

PubMed

A natural isolate, Candida tropicalis was tested for xylitol production from corn fiber and sugarcane bagasse hydrolysates. Fermentation of corn fiber and sugarcane bagasse hydrolysate showed xylose uptake and xylitol production, though these were very low, even after hydrolysate neutralization and treatments with activated charcoal and ion exchange resins. Initial xylitol production was found to be 0.43 g/g and 0.45 g/g of xylose utilised with corn fiber and sugarcane bagasse hydrolysate respectively. One of the critical factors for low xylitol production was the presence of inhibitors in these hydrolysates. To simulate influence of hemicellulosic sugar composition on xylitol yield, three different combinations of mixed sugar control experiments, without the presence of any inhibitors, have been performed and the strain produced 0.63 g/g, 0.68 g/g and 0.72 g/g of xylose respectively. To improve yeast growth and xylitol production with these hydrolysates, which contain inhibitors, the cells were adapted by sub culturing in the hydrolysate containing medium for 25 cycles. After adaptation the organism produced more xylitol 0.58 g/g and 0.65 g/g of xylose with corn fiber hydrolysate and sugarcane bagasse hydrolysate respectively. PMID:16242318

Rao, R Sreenivas; Jyothi, Ch Pavana; Prakasham, R S; Sarma, P N; Rao, L Venkateswar

2006-10-01

72

Adaptation and reutilization of Candida guilliermondii cells for xylitol production in bagasse hydrolysate.  

PubMed

The xylitol productivity increased by about 15% with the use of cells of Candida guilliermondii FTI 20037 previously recycled through four consecutive batch cultures and adapted to the sugar cane bagasse hemicellulosic hydrolysate. Furthermore, the more concentrated the hydrolysate, the more necessary was the adaptation of the cells, owing to the presence of toxic substances at high concentration which inhibited the xylose-xylitol conversion by the yeast. PMID:9542108

Sene, L; Felipe, M G; Vitolo, M; Silva, S S; Mancilha, I M

1998-01-01

73

The use of ion mobility mass spectrometry for isomer composition determination extracted from se-rich yeast.  

PubMed

The isomer ratio determination of a selenium-containing metabolite produced by Se-rich yeast was performed. Electrospray ionization and ion mobility mass spectrometry (IM-MS) were unsuccessfully used in order to resolve the isomers according to their collisional cross section (CCS) difference. The isomer ratio determination of 2,3-dihydroxypropionylselenocystathionine was performed after multidimensional liquid chromatography preconcentration from a water extract of Se-rich yeast using preparative size exclusion, anion exchange, and capillary reverse phase columns coupled to IM-MS. 4'-nitrobenzo-15-crown-5 ether, a selective shift reagent (SSR), was added after the last chromatographic dimension in order to specifically increase the CCS of one of the isomers by the formation of a stable host-guest system with the crown ether. Both isomers were consequently fully resolved by IM-MS, and the relative ratio of the isomers was determined to be 11-13% and 87-89%. The present data compared favorably with the literature to support the analytical strategy despite the lack of an authentic standard for method validation. In addition, computational chemistry methods were successfully applied to design the SSR and to support the experimental data. PMID:25295845

Far, Johann; Delvaux, Cédric; Kune, Christopher; Eppe, Gauthier; de Pauw, Edwin

2014-11-18

74

Yeast ecology of Kombucha fermentation  

Microsoft Academic Search

Kombucha is a traditional fermentation of sweetened tea, involving a symbiosis of yeast species and acetic acid bacteria. Despite reports of different yeast species being associated with the fermentation, little is known of the quantitative ecology of yeasts in Kombucha. Using oxytetracycline-supplemented malt extract agar, yeasts were isolated from four commercially available Kombucha products and identified using conventional biochemical and

Ai Leng Teoh; Gillian Heard; Julian Cox

2004-01-01

75

The sequential exposure to jasmonate, salicylic acid and yeast extract promotes sanguinarine accumulation in Argemone mexicana cell cultures.  

PubMed

The effects of the sequential application of methyl jasmonate (MeJa), salicylic acid (SA) and yeast extract (YE) to Argemone mexicana cell cultures were compared to either the sole application of each elicitor, or to the three-partite mixture. The highest sanguinarine accumulation occurred using the sequential treatment (ninefold over unexposed control cultures), followed by the single application of YE (fivefold). The elicitor mixture produced less sanguinarine than sole exposure to YE but higher than MeJa alone. SA did not produce any effect. Transcripts corresponding to tyrosine decarboxylase and berberine bridge enzyme accumulated in treated cells, but did not correlate with alkaloid accumulation. Discrete epifluorescence foci, surrounding the nucleus and scattered throughout the cytoplasm of elicited cells, suggested the presence of alkaloid-accumulating vesicles which could participate in a mechanism to avoid sanguinarine toxicity. PMID:22009570

Trujillo-Villanueva, Karen; Rubio-Piña, Jorge; Monforte-González, Miriam; Ramírez-Benítez, Efraín; Vázquez-Flota, Felipe

2012-02-01

76

Draft Genome Sequence of Kluyveromyces marxianus Strain DMB1, Isolated from Sugarcane Bagasse Hydrolysate  

PubMed Central

We determined the genome sequence of a thermotolerant yeast, Kluyveromyces marxianus strain DMB1, isolated from sugarcane bagasse hydrolysate, and the sequence provides further insights into the genomic differences between this strain and other reported K. marxianus strains. The genome described here is composed of 11,165,408 bases and has 4,943 protein-coding genes. PMID:25059876

Suzuki, Toshihiro; Hoshino, Tamotsu

2014-01-01

77

Draft Genome Sequence of Kluyveromyces marxianus Strain DMB1, Isolated from Sugarcane Bagasse Hydrolysate.  

PubMed

We determined the genome sequence of a thermotolerant yeast, Kluyveromyces marxianus strain DMB1, isolated from sugarcane bagasse hydrolysate, and the sequence provides further insights into the genomic differences between this strain and other reported K. marxianus strains. The genome described here is composed of 11,165,408 bases and has 4,943 protein-coding genes. PMID:25059876

Suzuki, Toshihiro; Hoshino, Tamotsu; Matsushika, Akinori

2014-01-01

78

Kinetic considerations about the study of alcoholic fermentations in starch hydrolysate  

Microsoft Academic Search

Alcoholic fermentations of starch hydrolysate by two different yeast strains, Saccharomyces cerevisiae (var. Vinal) and Saccharomyces oviformis (IMAP 383), have been studied in batch runs. In order to evaluate the different inhibition phenomena due to both substrate and product, a new kinetic equation is suggested. 23 references.

Attilio Converti; Patrizia Perego; Marco Del Borghi; Federico Parisi; Giuseppe Ferraiolo

1986-01-01

79

Cyanobacterial biomass as carbohydrate and nutrient feedstock for bioethanol production by yeast fermentation  

PubMed Central

Background Microbial bioconversion of photosynthetic biomass is a promising approach to the generation of biofuels and other bioproducts. However, rapid, high-yield, and simple processes are essential for successful applications. Here, biomass from the rapidly growing photosynthetic marine cyanobacterium Synechococcus sp. PCC 7002 was fermented using yeast into bioethanol. Results The cyanobacterium accumulated a total carbohydrate content of about 60% of cell dry weight when cultivated under nitrate limitation. The cyanobacterial cells were harvested by centrifugation and subjected to enzymatic hydrolysis using lysozyme and two alpha-glucanases. This enzymatic hydrolysate was fermented into ethanol by Saccharomyces cerevisiae without further treatment. All enzyme treatments and fermentations were carried out in the residual growth medium of the cyanobacteria with the only modification being that pH was adjusted to the optimal value. The highest ethanol yield and concentration obtained was 0.27 g ethanol per g cell dry weight and 30 g ethanol L-1, respectively. About 90% of the glucose in the biomass was converted to ethanol. The cyanobacterial hydrolysate was rapidly fermented (up to 20 g ethanol L-1 day-1) even in the absence of any other nutrient additions to the fermentation medium. Conclusions Cyanobacterial biomass was hydrolyzed using a simple enzymatic treatment and fermented into ethanol more rapidly and to higher concentrations than previously reported for similar approaches using cyanobacteria or microalgae. Importantly, as well as fermentable carbohydrates, the cyanobacterial hydrolysate contained additional nutrients that promoted fermentation. This hydrolysate is therefore a promising substitute for the relatively expensive nutrient additives (such as yeast extract) commonly used for Saccharomyces fermentations. PMID:24739806

2014-01-01

80

Production of Defatted Palm Kernel Cake Protein Hydrolysate as a Valuable Source of Natural Antioxidants  

PubMed Central

The aim of this study was to produce a valuable protein hydrolysate from palm kernel cake (PKC) for the development of natural antioxidants. Extracted PKC protein was hydrolyzed using different proteases (alcalase, chymotrypsin, papain, pepsin, trypsin, flavourzyme, and bromelain). Subsequently, antioxidant activity and degree of hydrolysis (DH) of each hydrolysate were evaluated using DPPH• radical scavenging activity and O-phthaldialdehyde spectrophotometric assay, respectively. The results revealed a strong correlation between DH and radical scavenging activity of the hydrolysates, where among these, protein hydrolysates produced by papain after 38 h hydrolysis exhibited the highest DH (91 ± 0.1%) and DPPH• radical scavenging activity (73.5 ± 0.25%) compared to the other hydrolysates. In addition, fractionation of the most effective (potent) hydrolysate by reverse phase high performance liquid chromatography indicated a direct association between hydrophobicity and radical scavenging activity of the hydrolysates. Isoelectric focusing tests also revealed that protein hydrolysates with basic and neutral isoelectric point (pI) have the highest radical scavenging activity, although few fractions in the acidic range also exhibited good antioxidant potential. PMID:22942692

Zarei, Mohammad; Ebrahimpour, Afshin; Abdul-Hamid, Azizah; Anwar, Farooq; Saari, Nazamid

2012-01-01

81

Budding yeast protein extraction and purification for the study of function, interactions, and post-translational modifications.  

PubMed

Homogenization by bead beating is a fast and efficient way to release DNA, RNA, proteins, and metabolites from budding yeast cells, which are notoriously hard to disrupt. Here we describe the use of a bead mill homogenizer for the extraction of proteins into buffers optimized to maintain the functions, interactions and post-translational modifications of proteins. Logarithmically growing cells expressing the protein of interest are grown in a liquid growth media of choice. The growth media may be supplemented with reagents to induce protein expression from inducible promoters (e.g. galactose), synchronize cell cycle stage (e.g. nocodazole), or inhibit proteasome function (e.g. MG132). Cells are then pelleted and resuspended in a suitable buffer containing protease and/or phosphatase inhibitors and are either processed immediately or frozen in liquid nitrogen for later use. Homogenization is accomplished by six cycles of 20 sec bead-beating (5.5 m/sec), each followed by one minute incubation on ice. The resulting homogenate is cleared by centrifugation and small particulates can be removed by filtration. The resulting cleared whole cell extract (WCE) is precipitated using 20% TCA for direct analysis of total proteins by SDS-PAGE followed by Western blotting. Extracts are also suitable for affinity purification of specific proteins, the detection of post-translational modifications, or the analysis of co-purifying proteins. As is the case for most protein purification protocols, some enzymes and proteins may require unique conditions or buffer compositions for their purification and others may be unstable or insoluble under the conditions stated. In the latter case, the protocol presented may provide a useful starting point to empirically determine the best bead-beating strategy for protein extraction and purification. We show the extraction and purification of an epitope-tagged SUMO E3 ligase, Siz1, a cell cycle regulated protein that becomes both sumoylated and phosphorylated, as well as a SUMO-targeted ubiquitin ligase subunit, Slx5. PMID:24300101

Szymanski, Eva Paige; Kerscher, Oliver

2013-01-01

82

Protein Hydrolysates/Peptides in Animal Nutrition  

NASA Astrophysics Data System (ADS)

The use of protein hydrolysates as an important nutrient for growth and maintenance has been increasing in animal nutrition. Although animal proteins and protein hydrolysates are widely used however, recently vegetable protein hydrolysates are gaining importance. This chapter reviews the use of protein hydrolysates developed by enzyme hydrolysis and by solid state fermentation process in animal nutrition especially for piglets and compares it with the standard products such as plasma and fishmeal.

McCalla, Jeff; Waugh, Terry; Lohry, Eric

83

Enzymatic protein hydrolysates in human nutrition  

Microsoft Academic Search

Protein hydrolysates constitute an alternative to intact proteins and elemental formulas in the development of special formulations designed to provide nutritional support to patients with different needs. The production of extensive protein hydrolysates by sequential action of endopeptidases and exoproteases coupled with the development of post-hydrolysis procedures is considered the most effective way to obtain protein hydrolysates with defined characteristics.

Alfonso Clemente

2000-01-01

84

Influence of Hen Age on the Response of Turkey Poults to Cold Stress, Escherichia coli Challenge, and Treatment with a Yeast Extract Antibiotic Alternative1  

Microsoft Academic Search

Two battery experiments were conducted to evaluate a commercial yeast extract feed supplement, Alphamune, in a cold stress-Escherichia coli challenge of 1-wk-old turkeys. Experiment 1 used 1-d-old male poults that were the progeny of 33-wk-old hens in their second week of lay. Experiment 2 used male poults of the same genetic line from 40-wk-old hens in their eighth week of

G. R. Huff; W. E. Huff; N. C. Rath; F. Solis; M. B. Farnell; A. M. Donoghue

85

Yeast RNA Extraction Using Hot Phenol See Khrer and Domdey, 1991, Methods Enzymol., 194:398-405. Note: Prepare dry ice  

E-print Network

73 Yeast RNA Extraction Using Hot Phenol · See Köhrer and Domdey, 1991, Methods Enzymol., 194:398-405. Note: Prepare dry ice powder in bucket. Preheat phenol/AE to 65°C. Heated phenol should not be re. Immediately add 500 µl hot phenol/AE (see below). Vortex for 15 seconds. Incubate at 65°C for 5 minutes

Aris, John P.

86

New protein hydrolysates from collagen wastes used as peptone for bacterial growth.  

PubMed

A simple and low-cost procedure was developed for the effective processing of native calf skin and blood wastes to produce protein hydrolysates. The method includes extraction of high-molecular-weight protein from the raw material, followed by enzymatic hydrolysis of the extracted residue. The enzymatic hydrolysis was performed by inexpensive commercial subtilisin DY, produced by Bacillus subtilis strain DY possessing high specific activity. The contents of protein, nitrogen, ash, and amino acids of the obtained hydrolysates were determined and compared with those of the commonly used commercial casein hydrolysate (Fluka Biochemica, Switzerland). The newly obtained calf skin hydrolysate, called Eladin, was found to be suitable as a low-cost alternative peptone in growth media of different microorganisms, such as Escherichia coli, Pseudomonas aeruginosa, Salmonella dublin, and Staphylococcus aureus. The method allows utilization of waste materials by converting them into valuable protein products that could find widespread application in microbiologic practice. PMID:17171464

Vasileva-Tonkova, E; Nustorova, M; Gushterova, A

2007-01-01

87

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

DOEpatents

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

Spindler, Diane D. (Indian Hills, CO); Grohmann, Karel (Littleton, CO); Wyman, Charles E. (Lakewood, CO)

1992-01-01

88

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

DOEpatents

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

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

1992-03-31

89

EFFECT OF NUTRIENT SUPPLEMENTATION OF CRUDE OR DETOXIFIED CONCENTRATED DISTILLED GRAPE MARC HEMICELLULOSIC HYDROLYSATES ON THE XYLITOL PRODUCTION BY Debaryomyces hansenii  

Microsoft Academic Search

Biosynthesis of xylitol using the yeast Debaryomyces hansenii NRRL Y-7426 was carried out using distilled grape marc (DGM) hemicellulosic hydrolysates directly concentrated by vacuum evaporation or after detoxification with activated charcoal. The effect of nutrient supplementation with vinasses, corn steep liquor (CSL) or commercial nutrients was explored. Using crude concentrated hemicellulosic hydrolysates, the maximum xylitol concentration, 11.3 g\\/L, was achieved after

José Manuel Salgado; Noelia Rodríguez; Sandra Cortés; José Manuel Domínguez

2012-01-01

90

Bioethanol production from the hydrolysate of rape stem in a surface-aerated fermentor.  

PubMed

In this study, we investigated the feasibility of producing bioethanol from the hydrolysate of rape stem. Specifically, the most ideal yeast strain was screened, and the microaeration was performed by surface aeration on a liquid medium surface. Among the yeast strains examined, Pichia stipitis CBS 7126 displayed the best performance in bioethanol production during the surface-aerated fermentor culture. Pichia stipitis CBS 7126 produced maximally 9.56 g/l of bioethanol from the initial total reducing sugars (about 28 g/l). The bioethanol yield was 0.397 (by the DNS method). Furthermore, this controlled surface aeration method holds promise for use in the bioethanol production from the xylose-containing lignocellulosic hydrolysate of biomass. PMID:21301200

Yeon, Ji-Hyeon; Lee, Sang-Eun; Choi, Woon Yong; Choi, Won-Seok; Kim, Il-Chul; Lee, Hyeon-Yong; Jung, Kyung-Hwan

2011-01-01

91

Xylose reductase and xylitol dehydrogenase activities of Candida guilliermondii as a function of different treatments of sugarcane bagasse hemicellulosic hydrolysate employing experimental design.  

PubMed

The sugarcane bagasse hydrolysate, which is rich in xylose, can be used as culture medium for Candida guilliermondii in xylitol production. However, the hydrolysate obtained from bagasse by acid hydrolysis at 120 degrees C for 20 min has by-products (acetic acid and furfural, among others), which are toxic to the yeast over certain concentrations. So, the hydrolysate must be pretreated before using in fermentation. The pretreatment variables considered were: adsorption time (15,37.5, and 60 min), type of acid used (H2So4 and H3Po4), hydrolysate concentration (original, twofold, and fourfold concentrated), and active charcoal (0.5, 1.75 and 3.0%). The suitability of the pretreatment was followed by measuring the xylose reductase (XR) and xylitol dehydrogenase (XD) activity of yeast grown in each treated hydrolysate. The response surface methodology (2(4) full factorial design with a centered face) indicated that the hydrolysate might be concentrated fourfold and the pH adjusted to 7.0 with CaO, followed by reduction to 5.5 with H3PO4. After that it was treated with active charcoal (3.0%) by 60 min. This pretreated hydrolysate attained the high XR/XD ratio of 4.5. PMID:12018268

Alves, Lourdes A; Vitolo, Michele; Felipe, Maria das Graças A; de Almeida e Silva, João Batista

2002-01-01

92

Alcoholic fermentation of carbon sources in biomass hydrolysates by Saccharomyces cerevisiae : current status  

Microsoft Academic Search

Fuel ethanol production from plant biomass hydrolysates by Saccharomyces cerevisiae is of great economic and environmental significance. This paper reviews the current status with respect to alcoholic fermentation of the main plant biomass-derived monosaccharides by this yeast. Wild-type S. cerevisiae strains readily ferment glucose, mannose and fructose via the Embden–Meyerhof pathway of glycolysis, while galactose is fermented via the Leloir

Antonius J. A. van Maris; Derek A. Abbott; Eleonora Bellissimi; Joost van den Brink; Marko Kuyper; Marijke A. H. Luttik; H. Wouter Wisselink; W. Alexander Scheffers; Johannes P. van Dijken; Jack T. Pronk

2006-01-01

93

A Four-Hour Yeast Bioassay for the Direct Measure of Estrogenic Activity in Wastewater without Sample Extraction, Concentration, or Sterilization  

PubMed Central

The assay described here represents an improved yeast bioassay that provides a rapid yet sensitive screening method for EDCs with very little hands-on time and without the need for sample preparation. Traditional receptor-mediated reporter assays in yeast were performed twelve to twenty four hours after ligand addition, used colorimetric substrates, and, in many cases, required high, non-physiological concentrations of ligand. With the advent of new chemiluminescent substrates a ligand-induced signal can be detected within thirty minutes using high picomolar to low nanomolar concentrations of estrogen. As a result of the sensitivity (EC50 for estradiol is ~ 0.7 nM) and the very short assay time (2-4 hours) environmental water samples can typically be assayed directly without sterilization, extraction, and concentration. Thus, these assays represent rapid and sensitive approaches for determining the presence of contaminants in environmental samples. As proof of principle, we directly assayed wastewater influent and effluent taken from a wastewater treatment plant in the El Paso, TX area for the presence of estrogenic activity. The data obtained in the four-hour yeast bioassay directly correlated with GC-mass spectrometry analysis of these same water samples. PMID:20074779

Balsiger, Heather A.; de la Torre, Roberto; Lee, Wen-Yee; Cox, Marc B.

2010-01-01

94

The isolation of an unidentified factor from yeast extract for the formate-pyruvate exchange reaction in streptococcus faecalis  

E-print Network

added to the reaction mimture containing- yeast emtraot only a 2N riduotion of activity. was TAMIL 1, Bigratii-n ni' tho factor on loper in s pyridinc butcnol-i. ztsr solvent system. . Band Boo Color of bands hy u+ve Activity Fold apmspmols... added to the reaction mimture containing- yeast emtraot only a 2N riduotion of activity. was TAMIL 1, Bigratii-n ni' tho factor on loper in s pyridinc butcnol-i. ztsr solvent system. . Band Boo Color of bands hy u+ve Activity Fold apmspmols...

Chen, Chi-sin

2012-06-07

95

Antioxidant and functional properties of collagen hydrolysates from Spanish mackerel skin as influenced by average molecular weight.  

PubMed

In the current study, the relationships between functional properties and average molecular weight (AMW) of collagen hydrolysates from Spanish mackerel (Scomberomorous niphonius) skin were researched. Seven hydrolysate fractions (5.04 ? AMW ? 47.82 kDa) from collagen of Spanish mackerel skin were obtained through the processes of acid extraction, proteolysis, and fractionation using gel filtration chromatography. The physicochemical properties of the collagen hydrolysate fractions were studied by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), gel filtration chromatography, scanning electron microscope (SEM) and Fourier transform infrared spectroscopy (FTIR). The results indicated that there was an inverse relationship between the antioxidant activities and the logarithm of the AMW of the hydrolysate fractions in the tested AMW range. However, the reduction of AMW significantly enhanced the solubility of the hydrolysate fractions, and a similar AMW decrease of the hydrolysate fractions negatively affected the emulsifying and foaming capacities. This presented as a positive correlation between the logarithm of AMW and emulsion stability index, emulsifying activity index, foam stability, and foam capacity. Therefore, these collagen hydrolysates with excellent antioxidant activities or good functionalities as emulsifiers could be obtained by controlling the effect of the digestion process on the AMW of the resultant hydrolysates. PMID:25090114

Chi, Chang-Feng; Cao, Zi-Hao; Wang, Bin; Hu, Fa-Yuan; Li, Zhong-Rui; Zhang, Bin

2014-01-01

96

Transcriptional activation of a geranylgeranyl diphosphate synthase gene, GGPPS2, isolated from Scoparia dulcis by treatment with methyl jasmonate and yeast extract.  

PubMed

A cDNA clone, designated SdGGPPS2, was isolated from young seedlings of Scoparia dulcis. The putative amino acid sequence of the translate of the gene showed high homology with geranylgeranyl diphosphate synthase (GGPPS) from various plant sources, and the N-terminal residues exhibited the characteristics of chloroplast targeting sequence. An appreciable increase in the transcriptional level of SdGGPPS2 was observed by exposure of the leaf tissues of S. dulcis to methyl jasmonate, yeast extract or Ca(2+) ionophore A23187. In contrast, SdGGPPS1, a homologous GGPPS gene of the plant, showed no or only negligible change in the expression level upon treatment with these stimuli. The truncated protein heterologously expressed in Escherichia coli in which the putative targeting domain was deleted catalyzed the condensation of farnesyl diphosphate and isopentenyl diphosphate to liberate geranylgeranyl diphosphate. These results suggested that SdGGPPS2 plays physiological roles in methyl jasmonate and yeast extract-induced metabolism in the chloroplast of S. dulcis cells. PMID:25027024

Yamamura, Y; Mizuguchi, Y; Taura, F; Kurosaki, F

2014-10-01

97

Response of scab-susceptible (McIntosh) and scab-resistant (Liberty) apple tissues to treatment with yeast extract and Venturia inaequalis.  

PubMed

Yeast extract and Venturia inaequalis treated intact scab-susceptible (McIntosh) and scab-resistant (Liberty) apple plants and their organs were analyzed for phenolic metabolites. The major phenolic compounds found in both non-treated and treated leaves were phloridzin and phloretin which accumulated in mM concentrations. Untreated and treated stems and roots contained only phloridzin as the major detectable metabolite during the course of the investigation. The accumulation of phloridzin and phloretin was not developmentally regulated, since they were present in both young and old leaves, and also in the intercellular washings of both scab-susceptible and scab-resistant plants. The major metabolites of both McIntosh and Liberty fruits were cinnamyl glucose and p-coumarylquinic acid, which increased 20-fold in Liberty fruit upon yeast extract treatment. The same compounds increased only 2-fold in McIntosh fruits. Minor compounds in the fruits of both cultivars were p-coumaric acid, phloridzin and phloretin, the latter compound being present at the threshold of detection. Biphenyl and dibenzofuran compounds, the major metabolites of elicitor treated Liberty cell suspension cultures, could not be detected in the intact plants. These results indicate differential response of plant organs and cell suspension cultures to elicitor treatment or pathogen invasion. PMID:12943766

Hrazdina, Geza; Borejsza-Wysocki, W

2003-09-01

98

Simultaneous saccharification and fermentation (SSF) using cellobiose fermenting yeast Brettanomyces custersii (CBS 5512)  

Microsoft Academic Search

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

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

1991-01-01

99

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

Microsoft Academic Search

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

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

1992-01-01

100

Radiation hydrolysate of tuna cooking juice with enhanced antioxidant properties  

NASA Astrophysics Data System (ADS)

Tuna protein hydrolysates are of increasing interest because of their potential application as a source of bioactive peptides. Large amounts of tuna cooking juice with proteins and extracts are produced during the process of tuna canning, and these cooking juice wastes cause environmental problems. Therefore, in this study, cooking juice proteins were hydrolyzed by irradiation for their utilization as functional additives. The degree of hydrolysis of tuna cooking juice protein increased from 0% to 15.1% at the absorbed doses of 50 kGy. To investigate the antioxidant activity of the hydrolysate, it was performed the ferric reducing antioxidant power (FRAP) assay, and the lipid peroxidation inhibitory and superoxide radical scavenging activities were measured. The FRAP values increased from 1470 ?M to 1930 ?M and IC50 on superoxide anion was decreased from 3.91 ?g/mL to 1.29 ?g/mL at 50 kGy. All of the antioxidant activities were increased in the hydrolysate, suggesting that radiation hydrolysis, which is a simple process that does not require an additive catalysts or an inactivation step, is a promising method for food and environmental industries.

Choi, Jong-il; Sung, Nak-Yun; Lee, Ju-Woon

2012-08-01

101

Actinopyga lecanora Hydrolysates as Natural Antibacterial Agents  

PubMed Central

Actinopyga lecanora, a type of sea cucumber commonly known as stone fish with relatively high protein content, was explored as raw material for bioactive peptides production. Six proteolytic enzymes, namely alcalase, papain, pepsin, trypsin, bromelain and flavourzyme were used to hydrolyze A. lecanora at different times and their respective degrees of hydrolysis (DH) were calculated. Subsequently, antibacterial activity of the A. lecanora hydrolysates, against some common pathogenic Gram positive bacteria (Bacillus subtilis and Staphylococcus aureus) and Gram negative bacteria (Escherichia coli, Pseudomonas aeruginosa, and Pseudomonas sp.) were evaluated. Papain hydrolysis showed the highest DH value (89.44%), followed by alcalase hydrolysis (83.35%). Bromelain hydrolysate after one and seven hours of hydrolysis exhibited the highest antibacterial activities against Pseudomonas sp., P. aeruginosa and E. coli at 51.85%, 30.07% and 30.45%, respectively compared to the other hydrolysates. Protein hydrolysate generated by papain after 8 h hydrolysis showed maximum antibacterial activity against S. aureus at 20.19%. The potent hydrolysates were further fractionated using RP-HPLC and antibacterial activity of the collected fractions from each hydrolysate were evaluated, wherein among them only three fractions from the bromelain hydrolysates exhibited inhibitory activities against Pseudomonas sp., P. aeruginosa and E. coli at 24%, 25.5% and 27.1%, respectively and one fraction of papain hydrolysate showed antibacterial activity of 33.1% against S. aureus. The evaluation of the relationship between DH and antibacterial activities of papain and bromelain hydrolysates revealed a meaningful correlation of four and six order functions. PMID:23222684

Ghanbari, Raheleh; Ebrahimpour, Afshin; Abdul-Hamid, Azizah; Ismail, Amin; Saari, Nazamid

2012-01-01

102

Applications of Protein Hydrolysates in Biotechnology  

NASA Astrophysics Data System (ADS)

By definition, protein hydrolysates are the products that are obtained after the hydrolysis of proteins and this can be achieved by enzymes, acid or alkali. This broad definition encompasses all the products of protein hydrolysis - peptides, amino acids and minerals present in the protein and acid/alkali used to adjust pH (Pasupuleti 2006). Protein hydrolysates contain variable side chains depending on the enzymes used. These side chains could be carboxyl, amino, imidazole, sulfhydryl, etc. and they may exert specific physiological roles in animal, microbial, insect and plant cells. This introductory chapter reviews the applications of protein hydrolysates in biotechnology. The word biotechnology is so broad and for the purpose of this book, we define it as a set of technologies such as cell culture technology, bioprocessing technology that includes fermentations, genetic engineering technology, microbiology, and so on. This chapter provides introduction and leads to other chapters on manufacturing and applications of protein hydrolysates in biotechnology.

Pasupuleti, Vijai K.; Holmes, Chris; Demain, Arnold L.

103

Co-fermentation of glucose, xylose and/or cellobiose by yeast  

DOEpatents

Provided herein are methods of using yeast cells to produce ethanol by contacting a mixture comprising xylose with a Spathaspora yeast cell under conditions suitable to allow the yeast to ferment at least a portion of the xylose to ethanol. The methods allow for efficient ethanol production from hydrolysates derived from lignocellulosic material and sugar mixtures including at least xylose and glucose or xylose, glucose and cellobiose.

Jeffries, Thomas W.; Willis, Laura B.; Long, Tanya M.; Su, Yi-Kai

2013-09-10

104

Release and ecological impact of algicidal hydrolysable polyphenols in Myriophyllum spicatum  

Microsoft Academic Search

Aqueous acetone extracts of shoots of Eurasian watermilfoil (Myriophyllum spicatum) exhibit a strong inhibitory action against various coccoid and filamentous cyanobacteria and to a slightly less extent against chlorophytes and diatoms. Bioassay-directed fractionation led to the isolation of a hydrolysable polyphenol, tellimagrandin II, which turned out to be the main inhibitory substance. Myriophyllum spicatum contains large amounts of this compound

Elisabeth M. Gross; Holger Meyer; Gerhard Schilling

1996-01-01

105

Molten salt destruction of base hydrolysate  

SciTech Connect

There is a great need for alternatives to open burn/open detonation of explosives and propellants from dismantled munitions. LANL has investigated the use of base hydrolysis for the demilitarization of explosives. Hydrolysates of Comp B, Octol, Tritonal, and PBXN-109 were processed in the pilot molten salt unit (in building 191). NOx and CO emissions were found to be low, except for CO from PBXN-109 processing. This report describes experimental results of the destruction of the base hydrolysates.

Watkins, B.E.; Kanna, R.L.; Chambers, R.D.; Upadhye, R.S.; Promeda, C.O.

1996-10-01

106

A yeast bioassay for direct measurement of thyroid hormone disrupting effects in water without sample extraction, concentration, or sterilization.  

PubMed

The present study introduces an improved yeast bioassay for rapid yet sensitive evaluation of thyroid hormone disruption at the level of thyroid receptor (TR) in environmental water samples. This assay does not require water sample preparation and thus requires very little hands-on time. Based on different ?-galactosidase substrates, two modified bioassays, a colorimetric bioassay and a chemiluminescent bioassay, were developed. The compounds tested included the known thyroid hormone 3,3',5-triiodo-l-thyronine (T3), the specific TR antagonist amiodarone hydrochloride (AH) and phthalate esters (PAEs), which potentially disrupt thyroid hormone signaling. The EC50 values for T3 were similar to those previously obtained using a 96-well plate bioassay. TR antagonism by AH was studied in the presence of 2.5 × 10(-7)M T3, and the concentration producing 20% of the maximum effect (RIC20) for AH was 3.1 × 10(-7)M and 7.8 × 10(-9)M for the colorimetric bioassay and chemiluminescent bioassay, respectively. None of the tested PAEs induced ?-galactosidase expression, but diethylhexyl phthalate, benzyl butyl phthalate and dibutyl phthalate demonstrated TR antagonism. Furthermore, water samples collected from Guanting reservoir in Beijing were evaluated. Although TR agonism was not observed, antagonism was detected in all water samples and is expressed as AH equivalents. The toxicology equivalent quantity values obtained by the chemiluminescent bioassay ranged from 21.2 ± 1.6 to 313.9 ± 28.8 ?g L(-1) AH, and similar values were obtained for the colorimetric bioassay. The present study shows that the modified yeast bioassay can be used as a valuable tool for quantification of thyroid hormone disrupting effects in environmental water samples. PMID:24355165

Li, Jian; Ren, Shujuan; Han, Shaolun; Li, Na

2014-04-01

107

Antigenicity for Humans of Cow Milk Caseins, Casein Hydrolysate and Casein Hydrolysate Fractions  

Microsoft Academic Search

Nentwich I., Szépfalusi Zs., Kunz C., Spuergin P., Urbanek R.: Antigenicity for Humans of Cow Milk Caseins, Casein Hydrolysate and Casein Hydrolysate Fractions. Acta Vet. Brno 2004, 73: 291-298. Cow milk casein consists of several fractions each of which have different structure and differing antigenicity. The aim of the study was to investigate the capacity of cow milk casein, casein

I. NENTWICH; Z. S. SZÉPFALUSI; C. KUNZ; P. SPUERGIN; R. URBANEK

2004-01-01

108

Xylitol production from wheat straw hemicellulosic hydrolysate: hydrolysate detoxification and carbon source used for inoculum preparation  

PubMed Central

Wheat straw hemicellulosic hydrolysate was used for xylitol bioproduction. The use of a xylose-containing medium to grow the inoculum did not favor the production of xylitol in the hydrolysate, which was submitted to a previous detoxification treatment with 2.5% activated charcoal for optimized removal of inhibitory compounds. PMID:24031226

Canilha, Larissa; Carvalho, Walter; Felipe, Maria das Gracas Almeida; de Almeida e Silva, Joao Batista

2008-01-01

109

Two-step process using immobilized Saccharomyces cerevisiae and Pichia stipitis for ethanol production from Ulva pertusa Kjellman hydrolysate.  

PubMed

We established a two-step production process using immobilized S. cerevisiae and P. stipitis yeast to produce ethanol from seaweed (U. pertusa Kjellman) hydrolysate. The process was designed to completely consume both glucose and xylose. In particular, the yeasts were immobilized using DEAE-corncob and DEAE-cotton, respectively. The first step of the process included a continuous column reactor using immobilized S. cerevisiae, and the second step included a repeated-batch reactor using immobilized P. stipitis. It was verified that the glucose and xylose in 20 L of medium containing the U. pertusa Kjellman hydrolysate was converted completely to about 5.0 g/l ethanol through the two-step process, in which the overall ethanol yield from total reducing sugar was 0.37 and the volumetric ethanol productivity was 0.126 g/ l/h. The volumetric ethanol productivity of the two-step process was about 2.7 times greater than that when P. stipitis was used alone for ethanol production from U. pertusa Kjellman hydrolysate. In addition, the overall ethanol yield from glucose and xylose was superior to that when P. stipitis was used alone for ethanol production. This two-step process will not only contribute to the development of an integrated process for ethanol production from glucose and xylose-containing biomass hydrolysates, but could also be used as an alternative method for ethanol production. PMID:23851267

Lee, Sang-Eun; Kim, Yi-Ok; Choi, Woo Yong; Kang, Do-Hyung; Lee, Hyeon-Yong; Jung, Kyung-Hwan

2013-10-28

110

Occurrence and Growth of Yeasts in Yogurts  

PubMed Central

Yogurts purchased from retail outlets were examined for the presence of yeasts by being plated onto oxytetracycline malt extract agar. Of the 128 samples examined, 45% exhibited yeast counts above 103 cells per g. A total of 73 yeast strains were isolated and identified as belonging to the genera Torulopsis, Kluyveromyces, Saccharomyces, Candida, Rhodotorula, Pichia, Debaryomyces, and Sporobolomyces. Torulopsis candida and Kluyveromyces fragilis were the most frequently isolated species, followed by Saccharomyces cerevisiae, Rhodotorula rubra, Kluyveromyces lactis, and Torulopsis versatilis. The growth of yeasts in yogurts was related to the ability of the yeasts to grow at refrigeration temperatures, to ferment lactose and sucrose, and to hydrolyze milk casein. Most yeast isolates grew in the presence of 100 ?g of sorbate and benzoate preservatives per ml. Higher yeast counts from yogurts were obtained when the yogurts were plated onto oxytetracycline malt extract agar than when they were plated onto acidified malt extract agar. PMID:16345853

Suriyarachchi, V. R.; Fleet, G. H.

1981-01-01

111

Evaluation of red chicory extract as a natural antioxidant by pure lipid oxidation and yeast oxidative stress response as model systems.  

PubMed

The search for renewable and abundant sources of antioxidants has recently focused on agricultural byproducts, especially promising due to their natural origins and low costs. In particular, plant raw materials are sources of important compounds such as dietary fiber, carotenoids, tocopherols, and polyphenolics, which are mostly discarded during harvesting and processing. Among these vegetal crops, red chicory is attractive because of the large quantity of its byproducts (residues as leaves and stems); moreover, there is no information on its role as a food and feed ingredient. In this study, red chicory leaf residue was evaluated as a natural substitute for synthetic antioxidants for the food and feed industry. After lyophilization, a red chicory extract (RC) was characterized for its phenolic profile and its oxidative stability as compared to BHT. RC was shown to reduce lipid peroxidation of different oils in the Rancimat test. In addition, the antioxidant property of RC was studied in a model system by evaluating the Saccharomyces cerevisiae response to oxidative stress by means of gene expression. In this analysis, the RC extract, added to the yeast culture prior to oxidative stress induction, exhibited a pleiotropic protective effect on stress responsive genes. PMID:21488640

Lante, Anna; Nardi, Tiziana; Zocca, Federico; Giacomini, Alessio; Corich, Viviana

2011-05-25

112

Measurement of the inhibitory potential and detoxification of biomass pretreatment hydrolysate for ethanol production  

SciTech Connect

The Microtox assay represents a rapid, accurate, and reproducible method for determining general microbial toxicity. This assay was used to evaluate the relative toxicity of a variety of hydrolysate samples derived from dilute-acid and alkaline biomass pretreatment. Toxicity is elicited from biomass degradation products, such as furfural, hydroxymethyl furfural, and acetic acid, generated during pretreatment. Microtox results indicate that the pretreatment samples examined ranged from 9 to 71 toxicity units (TU). Correlations of TU and sample absorbance at several wavelengths were evaluated for all sample series. Sample TU values best agreed with absorbance at 230 nm, but the unsatisfactory fit suggests that absorbance should not be used as an absolute measure of sample toxicity. Microtox data for pretreatment hydrolysate samples were correlated with the inhibition experienced by the ethanologenic yeast, Saccharomyces cerevisiae strain D{sub 5}A, during the simultaneous saccharification and fermentation (SSF) process of pretreated biomass. None of the alkaline pretreatment conditions produced inhibition during SSF. However, the acid pretreatment conditions did produce a wide range of inhibitory and noninhibitory hydrolysates. In general, fermentation was inhibited for acid-pretreated hydrolysate samples with values exceeding 45 TU. Preliminary studies that focused on reducing hydrolysate sample toxicity (detoxification) indicate that adding perlite and zeolite had little effect. However, the use of charcoal, a universal flocculent, or ion-exchange resins significantly reduced sample toxicity, holding promise for the efficient bioconversion of pretreated biomass to ethanol. Moreover, the developed toxicity measurement assay can quickly monitor the quality of the pretreatment process. In this way, biomass conversion operation processes can be reliably controlled at the pilot and commercial scales. 4 refs., 4 figs., 3 tabs.

Rivard, C.J.; Engel, R.E.; Nagle, N.J. [National Renewable Energy Lab., Golden, CO (United States)] [and others

1996-12-31

113

State of the Art Manufacturing of Protein Hydrolysates  

NASA Astrophysics Data System (ADS)

The use of protein hydrolysates in microbiological media has been in existence for several decades and the basic manufacturing process of protein hydrolysates has remained the same. However, with increasing use of protein hydrolysates in specialized applications such as animal cell culture processes, the manufacturing of protein hydrolysates has dramatically improved and is still in its infancy to uncover the specific peptide, peptides and combination of individual amino acids that produce intended effects for that application. This will change as the protein hydrolysate manufacturers and end-users exchange information and work towards the common goal of developing the best protein hydrolysates for specific applications. This chapter will review the generic manufacturing of protein hydrolysates describing individual unit operations, problems faced by manufacturers and suggestions for obtaining consistent product and guidelines for the end-users in getting regulatory support and setting up reliable specifications. Finally the chapter concludes with future trends of protein hydrolysates.

Pasupuleti, Vijai K.; Braun, Steven

114

Endogenous hydrogen peroxide is a key factor in the yeast extract-induced activation of biphenyl biosynthesis in cell cultures of Sorbus aucuparia.  

PubMed

Biphenyls are unique phytoalexins produced by plants belonging to Pyrinae, a subtribe of the economically important Rosaceae family. The formation of aucuparin, a well-known biphenyl, is induced by yeast extract (YE) in cell cultures of Sorbus aucuparia. However, the molecular mechanism underlying YE-induced activation of biphenyl biosynthesis remains unknown. Here we demonstrate that the addition of YE to the cell cultures results in a burst of reactive oxygen species (ROS; H(2)O(2) and O(2) (-)), followed by transcriptional activation of the biphenyl synthase 1 gene (BIS1) encoding the key enzyme of the biphenyl biosynthetic pathway and aucuparin accumulation. Pretreatment of the cell cultures with ROS scavenger dihydrolipoic acid and NADPH oxidase-specific inhibitor diphenylene iodonium abolished all of the above YE-induced biological events. However, when the cell cultures was pretreated with superoxide dismutase specific inhibitor N,N-diethyldithiocarbamic acid, although O(2) (-) continued to be generated, the H(2)O(2) accumulation, BIS1 expression and aucuparin production were blocked. Interestingly, exogenous supply of H(2)O(2) in the range of 0.05-10 mM failed to induce aucuparin accumulation. These results indicate that endogenous generation of H(2)O(2) rather than that of O(2) (-) is a key factor in YE-induced accumulation of biphenyl phytoalexins in cell cultures of S. aucuparia. PMID:22086110

Qiu, Xiaofang; Lei, Caiyan; Huang, Lili; Li, Xing; Hao, He; Du, Zhigao; Wang, Hong; Ye, Hechun; Beerhues, Ludger; Liu, Benye

2012-01-01

115

Xuezhikang, extract of red yeast rice, inhibited tissue factor and hypercoagulable state through suppressing nicotinamide adenine dinucleotide phosphate oxidase and extracellular signal-regulated kinase activation.  

PubMed

Xuezhikang, extract of red yeast rice, is a traditional Chinese medicine with multiple cardioprotective effect. It contains a family of naturally occurring statins, such as lovastatin. Tissue factor (TF) is overexpressed in macrophages of lipid core plaques, which display high procoagulant activity and seem to be a potentially target for anti-atherothrombosis. Therefore, the purpose of this study was to explore the effect and possible molecular mechanisms of xuezhikang on inhibiting TF expression and hypercoagulable state and the differences compared with lovastatin. Our results showed that xuezhikang significantly suppressed oxidized low-density lipoprotein-induced TF expression in macrophages in a concentration-dependent manner. Xuezhikang reduced nicotinamide adenine dinucleotide phosphate oxidase activity by decreasing membrane translocation of p47 through inhibition of extracellular signal-regulated kinase 1/2 activation. Nicotinamide adenine dinucleotide phosphate inhibitor (diphenyleneiodonium) also inhibited the oxidized low-density lipoprotein-induced TF expression, similar to the effects of xuezhikang. Furthermore, consistent with the severity of aortic atherosclerosis, xuezhikang (300 mg·kg·d) significantly reduced blood coagulation activation and TF expression in high-cholesterol diet-induced atherosclerotic rats. In addition, xuezhikang was more potent than lovastatin on inhibiting the expression of TF and nicotinamide adenine dinucleotide phosphate oxidase activation. These observations provide evidences that inhibition of xuezhikang on hypercoagulation and TF expression may partly account for its cardioprotective benefits. PMID:21697731

Li, Pei; Yang, Yabing; Liu, Meilin

2011-09-01

116

Hydrolysates of lignocellulosic materials for biohydrogen production  

PubMed Central

Lignocellulosic materials are commonly used in bio-H2 production for the sustainable energy resource development as they are abundant, cheap, renewable and highly biodegradable. In the process of the bio-H2 production, the pretreated lignocellulosic materials are firstly converted to monosaccharides by enzymolysis and then to H2 by fermentation. Since the structures of lignocellulosic materials are rather complex, the hydrolysates vary with the used materials. Even using the same lignocellulosic materials, the hydrolysates also change with different pretreatment methods. It has been shown that the appropriate hydrolysate compositions can dramatically improve the biological activities and bio-H2 production performances. Over the past decades, hydrolysis with respect to different lignocellulosic materials and pretreatments has been widely investigated. Besides, effects of the hydrolysates on the biohydrogen yields have also been examined. In this review, recent studies on hydrolysis as well as their effects on the biohydrogen production performance are summarized. [BMB Reports 2013; 46(5): 244-251] PMID:23710634

Chen, Rong; Wang, Yong-Zhong; Liao, Qiang; Zhu, Xun; Xu, Teng-Fei

2013-01-01

117

Improving lipid production from bagasse hydrolysate with Trichosporon fermentans by response surface methodology.  

PubMed

Oleaginous yeast Trichosporon fermentans was proved to be able to use sulphuric acid-treated sugar cane bagasse hydrolysate as substrate to grow and accumulate lipid. Activated charcoal was shown as effective as the more expensive resin Amberlite XAD-4 for removing the inhibitors from the hydrolysate. To further improve the lipid production, response surface methodology (RSM) was used and a 3-level 4-factor Box-Behnken design was adopted to evaluate the effects of C/N ratio, inoculum concentration, initial pH and fermentation time on the cell growth and lipid accumulation of T. fermentans. Under the optimum conditions (C/N ratio 165, inoculum concentration 11%, initial pH 7.6 and fermentation time 9 days), a lipid concentration of 15.8g/L, which is quite close to the predicted value of 15.6g/L, could be achieved after cultivation of T. fermentans at 25°C on the pretreated bagasse hydrolysate and the corresponding lipid coefficient (lipid yield per mass of sugar, %) was 14.2. These represent a 32.8% improvement in the lipid concentration and a 21.4% increase in the lipid coefficient compared with the original values before optimization (11.9g/L and 11.7). This work further demonstrates that T. fermentans is a promising strain for lipid production and thus biodiesel preparation from abundant and inexpensive lignocellulosic materials. PMID:21458601

Huang, Chao; Wu, Hong; Li, Ri-feng; Zong, Min-hua

2012-02-15

118

Modulation of Intestinal Inflammation by Yeasts and Cell Wall Extracts: Strain Dependence and Unexpected Anti-Inflammatory Role of Glucan Fractions  

Microsoft Academic Search

Yeasts and their glycan components can have a beneficial or adverse effect on intestinal inflammation. Previous research has shown that the presence of Saccharomyces cerevisiae var. boulardii (Sb) reduces intestinal inflammation and colonization by Candida albicans. The aim of this study was to identify dietary yeasts, which have comparable effects to the anti-C. albicans and anti-inflammatory properties of Sb and

Samir Jawhara; Khalid Habib; François Maggiotto; Georges Pignede; Pascal Vandekerckove; Emmanuel Maes; Laurent Dubuquoy; Thierry Fontaine; Yann Guerardel; Daniel Poulain

2012-01-01

119

deficient in a chloroplastic starch-hydrolysing enzyme  

E-print Network

The aim of this work was to identify enzymes that participate in the degradation of transitory starch in Arabidopsis. A mutant line was isolated by screening leaves at the end of the night for the presence of starch. The mutant had a higher starch content than the wild-type throughout the diurnal cycle. This accumulation was due to a reduction in starch breakdown, leading to an imbalance between the rates of synthesis and degradation. No reduction in the activity of endo-amylase (?-amylase), ?-amylase, starch phosphorylase, maltase, pullulanase or D-enzyme could be detected in crude extracts of leaves of the mutant. However, native PAGE in gels containing amylopectin revealed that a starch-hydrolysing activity, putatively identified as an endo-amylase and present in wild-type chloroplasts, was absent or appreciably reduced in the mutant. This is the first time that a specific enzyme required for starch degradation has been identified in leaves.

Samuel C. Zeeman; Fred Northrop; Alison M. Smith; Tom Ap Rees; John Innes Centre; Norfolk Nr Uh

120

Yeast Infections  

MedlinePLUS

Candida is the scientific name for yeast. It is a fungus that lives almost everywhere, including in ... infection that causes white patches in your mouth Candida esophagitis is thrush that spreads to your esophagus, ...

121

Identification of oleaginous yeast strains able to accumulate high intracellular lipids when cultivated in alkaline pretreated corn stover.  

PubMed

Microbial oil is a potential alternative to food/plant-derived biodiesel fuel. Our previous screening studies identified a wide range of oleaginous yeast species, using a defined laboratory medium known to stimulate lipid accumulation. In this study, the ability of these yeasts to grow and accumulate lipids was further investigated in synthetic hydrolysate (SynH) and authentic ammonia fiber expansion (AFEX™)-pretreated corn stover hydrolysate (ACSH). Most yeast strains tested were able to accumulate lipids in SynH, but only a few were able to grow and accumulate lipids in ACSH medium. Cryptococcus humicola UCDFST 10-1004 was able to accumulate as high as 15.5 g/L lipids, out of a total of 36 g/L cellular biomass when grown in ACSH, with a cellular lipid content of 40 % of cell dry weight. This lipid production is among the highest reported values for oleaginous yeasts grown in authentic hydrolysate. Preculturing in SynH media with xylose as sole carbon source enabled yeasts to assimilate both glucose and xylose more efficiently in the subsequent hydrolysate medium. This study demonstrates that ACSH is a suitable medium for certain oleaginous yeasts to convert lignocellullosic sugars to triacylglycerols for production of biodiesel and other valuable oleochemicals. PMID:25052467

Sitepu, Irnayuli R; Jin, Mingjie; Fernandez, J Enrique; da Costa Sousa, Leonardo; Balan, Venkatesh; Boundy-Mills, Kyria L

2014-09-01

122

Yeast adaptation on softwood prehydrolysate.  

PubMed

Several strains and genera of yeast, including Saccharomyces cerevisiae D5A, Pachysolen tannophilus, S. cerevisiae K-1, Brettanomyces custersii, Candida shehatae, and Candida acidothermophilum, are screened for growth on dilute acid-pretreated softwood prehydrolysate. Selected softwood species found in forest underbrush of the western United States, which contain predominantly hexosan hemicellulose, were studied. This phase of the work emphasized debarked Douglas fir. The two best initial isolates were gradually selected for improved growth by adaptation to increasing prehydrolysate concentrations in batch culture, with due consideration of nutrient requirements. Microaerophilic conditions were evaluated to encourage tolerance of pretreatment hydrolysate, as well as ethanol product. Adaptation and simultaneous saccharification and fermentation (SSF) results are used to illustrate improved performance with an adapted strain, compared to the wild type. PMID:9627379

Keller, F A; Bates, D; Ruiz, R; Nguyen, Q

1998-01-01

123

Thermophilic lactic acid production on hemicellulose hydrolysate.  

PubMed

Lactic acid has many applications. It can be utilised as road-deicing agent, in the food industry or--after polymerisation--as a biodegradable plastic. The use of lignocellulose biomass will significantly increase the competitiveness of lactic acid-based polymers compared to conventional petroleum based plastics. The Institute for Agrobiotechnology in Tulln (IFA-Tulln) developed a process to apply renewable resources as cheap feedstock for production of lactic acid. The utilisation of thermophiles combined with a suitable pretreatment method enables a fermentation under non sterile conditions with detoxified hemicellulosic hydrolysates. This paper presents growth toxicity tests and batch experiments with bagasse hydrolysate, which were conducted to determine the fermentability of thermophilic wild type strains. PMID:15954612

Thomasser, C; Danner, H; Neureiter, M; Saidi, B; Braun, R

2001-01-01

124

Mixed culture of Bacillus circulans WL12 and Phaffia Rhodozyma on different carbon sources: Yeast-wall lytic enzyme production and extractability of astaxanthin  

Microsoft Academic Search

Summary Lytic enzyme production byBacillus circulans WL-12 and modification of the red yeastPhaffia rhodozyma in mixed culture, is feasible on some simple sugars other than glucose. Advantages of the mixed culture are discussed.

R. N. Okagbue; M. J. Lewis

1983-01-01

125

Hot water extraction and steam explosion as pretreatments for ethanol production from spruce bark.  

PubMed

Spruce bark is a source of interesting polyphenolic compounds and also a potential but little studied feedstock for sugar route biorefinery processes. Enzymatic hydrolysis and fermentation of spruce bark sugars to ethanol were studied after three different pretreatments: steam explosion (SE), hot water extraction (HWE) at 80 °C, and sequential hot water extraction and steam explosion (HWE+SE), and the recovery of different components was determined during the pretreatments. The best steam explosion conditions were 5 min at 190 °C without acid catalyst based on the efficiency of enzymatic hydrolysis of the material. However, when pectinase was included in the enzyme mixture, the hydrolysis rate and yield of HWE bark was as good as that of SE and HWE+SE barks. Ethanol was produced efficiently with the yeast Saccharomyces cerevisiae from the pretreated and hydrolysed materials suggesting the suitability of spruce bark to various lignocellulosic ethanol process concepts. PMID:22613888

Kemppainen, Katariina; Inkinen, Jenni; Uusitalo, Jaana; Nakari-Setälä, Tiina; Siika-aho, Matti

2012-08-01

126

Genome-wide screening of Saccharomyces cerevisiae genes required to foster tolerance towards industrial wheat straw hydrolysates.  

PubMed

The presence of toxic compounds derived from biomass pre-treatment in fermentation media represents an important drawback in second-generation bio-ethanol production technology and overcoming this inhibitory effect is one of the fundamental challenges to its industrial production. The aim of this study was to systematically identify, in industrial medium and at a genomic scale, the Saccharomyces cerevisiae genes required for simultaneous and maximal tolerance to key inhibitors of lignocellulosic fermentations. Based on the screening of EUROSCARF haploid mutant collection, 242 and 216 determinants of tolerance to inhibitory compounds present in industrial wheat straw hydrolysate (WSH) and in inhibitor-supplemented synthetic hydrolysate were identified, respectively. Genes associated to vitamin metabolism, mitochondrial and peroxisomal functions, ribosome biogenesis and microtubule biogenesis and dynamics are among the newly found determinants of WSH resistance. Moreover, PRS3, VMA8, ERG2, RAV1 and RPB4 were confirmed as key genes on yeast tolerance and fermentation of industrial WSH. PMID:25287021

Pereira, Francisco B; Teixeira, Miguel C; Mira, Nuno P; Sá-Correia, Isabel; Domingues, Lucília

2014-12-01

127

Economical production of poly(?-l-lysine) and poly(l-diaminopropionic acid) using cane molasses and hydrolysate of streptomyces cells by Streptomyces albulus PD-1.  

PubMed

Poly(?-L-lysine) (?-PL) and poly(L-diaminopropionic acid) (PDAP) co-production by Streptomyces albulus PD-1 from cane molasses and hydrolysate of strepyomyces cells (HSC) was investigated for the first time in this study. The optimal initial total sugar concentration of the cane molasses pretreated with sulfuric acid was determined to be 20 g L(-1), and HSC could substitute for yeast extract for ?-PL and PDAP co-production. When fed-batch fermentation was performed in 1t fermentor with pretreated cane molasses and HSC, 20.6 ± 0.5 g L(-1) of ?-PL and 5.2 ± 0.6 g L(-1) of PDAP were obtained. The amount of strepyomyces cells obtained in one fed-batch fermentation is sufficient to prepare the HSC to satisfy the demand of subsequent fermentations, thus the self-cycling of organic nitrogen source becomes available. These results suggest that the low-cost cane molasses and HSC can be used for the economical production of ?-PL and PDAP by S. albulus PD-1. PMID:24861999

Xia, Jun; Xu, Zhaoxian; Xu, Hong; Liang, Jinfeng; Li, Sha; Feng, Xiaohai

2014-07-01

128

Collagen hydrolysate based collagen/hydroxyapatite composite materials  

NASA Astrophysics Data System (ADS)

The aim of this study was to study the influence of collagen hydrolysate (HAS) on the formation of ternary collagen-hydrolysate/hydroxyapatite composite materials (COLL-HAS/HA). During the precipitation process of HA, a large amount of brushite is resulted at pH = 7 but, practically pure HA is obtained at pH ? 8. The FTIR data reveal the duplication of the most important collagen absorption bands due to the presence of the collagen hydrolysate. The presence of collagen hydrolysate is beneficial for the management of bone and joint disorders such as osteoarthritis and osteoporosis.

Ficai, Anton; Albu, Madalina Georgiana; Birsan, Mihaela; Sonmez, Maria; Ficai, Denisa; Trandafir, Viorica; Andronescu, Ecaterina

2013-04-01

129

Dissecting a complex chemical stress: chemogenomic profiling of plant hydrolysates  

PubMed Central

The efficient production of biofuels from cellulosic feedstocks will require the efficient fermentation of the sugars in hydrolyzed plant material. Unfortunately, plant hydrolysates also contain many compounds that inhibit microbial growth and fermentation. We used DNA-barcoded mutant libraries to identify genes that are important for hydrolysate tolerance in both Zymomonas mobilis (44 genes) and Saccharomyces cerevisiae (99 genes). Overexpression of a Z. mobilis tolerance gene of unknown function (ZMO1875) improved its specific ethanol productivity 2.4-fold in the presence of miscanthus hydrolysate. However, a mixture of 37 hydrolysate-derived inhibitors was not sufficient to explain the fitness profile of plant hydrolysate. To deconstruct the fitness profile of hydrolysate, we profiled the 37 inhibitors against a library of Z. mobilis mutants and we modeled fitness in hydrolysate as a mixture of fitness in its components. By examining outliers in this model, we identified methylglyoxal as a previously unknown component of hydrolysate. Our work provides a general strategy to dissect how microbes respond to a complex chemical stress and should enable further engineering of hydrolysate tolerance. PMID:23774757

Skerker, Jeffrey M; Leon, Dacia; Price, Morgan N; Mar, Jordan S; Tarjan, Daniel R; Wetmore, Kelly M; Deutschbauer, Adam M; Baumohl, Jason K; Bauer, Stefan; Ibanez, Ana B; Mitchell, Valerie D; Wu, Cindy H; Hu, Ping; Hazen, Terry; Arkin, Adam P

2013-01-01

130

Yeast ecology of Kombucha fermentation.  

PubMed

Kombucha is a traditional fermentation of sweetened tea, involving a symbiosis of yeast species and acetic acid bacteria. Despite reports of different yeast species being associated with the fermentation, little is known of the quantitative ecology of yeasts in Kombucha. Using oxytetracycline-supplemented malt extract agar, yeasts were isolated from four commercially available Kombucha products and identified using conventional biochemical and physiological tests. During the fermentation of each of the four products, yeasts were enumerated from both the cellulosic pellicle and liquor of the Kombucha. The number and diversity of species varied between products, but included Brettanomyces bruxellensis, Candida stellata, Schizosaccharomyces pombe, Torulaspora delbrueckii and Zygosaccharomyces bailii. While these yeast species are known to occur in Kombucha, the enumeration of each species present throughout fermentation of each of the four Kombucha cultures demonstrated for the first time the dynamic nature of the yeast ecology. Kombucha fermentation is, in general, initiated by osmotolerant species, succeeded and ultimately dominated by acid-tolerant species. PMID:15282124

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

2004-09-01

131

Conversion of C6 and C5 sugars in undetoxified wet exploded bagasse hydrolysates using Scheffersomyces (Pichia) stipitis CBS6054.  

PubMed

Sugarcane bagasse is a potential feedstock for cellulosic ethanol production, rich in both glucan and xylan. This stresses the importance of utilizing both C6 and C5 sugars for conversion into ethanol in order to improve the process economics. During processing of the hydrolysate degradation products such as acetate, 5-hydroxymethylfurfural (HMF) and furfural are formed, which are known to inhibit microbial growth at higher concentrations. In the current study, conversion of both glucose and xylose sugars into ethanol in wet exploded bagasse hydrolysates was investigated without detoxification using Scheffersomyces (Pichia) stipitis CBS6054, a native xylose utilizing yeast strain. The sugar utilization ratio and ethanol yield (Yp/s) ranged from 88-100% and 0.33-0.41?±?0.02 g/g, respectively, in all the hydrolysates tested. Hydrolysate after wet explosion at 185°C and 6 bar O2, composed of mixed sugars (glucose and xylose) and inhibitors such as acetate, HMF and furfural at concentrations of 3.2?±?0.1, 0.4 and 0.5 g/l, respectively, exhibited highest cell growth rate of 0.079 g/l/h and an ethanol yield of 0.39?±?0.02 g/g sugar converted. Scheffersomyces stipitis exhibited prolonged fermentation time on bagasse hydrolysate after wet explosion at 200°C and 6 bar O2 where the inhibitors concentration was further increased. Nonetheless, ethanol was produced up to 18.7?±?1.1 g/l resulting in a yield of 0.38?±?0.02 g/g after 82 h of fermentation. PMID:23895663

Biswas, Rajib; Uellendahl, Hinrich; Ahring, Birgitte K

2013-01-01

132

Conversion of C6 and C5 sugars in undetoxified wet exploded bagasse hydrolysates using Scheffersomyces (Pichia) stipitis CBS6054  

PubMed Central

Sugarcane bagasse is a potential feedstock for cellulosic ethanol production, rich in both glucan and xylan. This stresses the importance of utilizing both C6 and C5 sugars for conversion into ethanol in order to improve the process economics. During processing of the hydrolysate degradation products such as acetate, 5-hydroxymethylfurfural (HMF) and furfural are formed, which are known to inhibit microbial growth at higher concentrations. In the current study, conversion of both glucose and xylose sugars into ethanol in wet exploded bagasse hydrolysates was investigated without detoxification using Scheffersomyces (Pichia) stipitis CBS6054, a native xylose utilizing yeast strain. The sugar utilization ratio and ethanol yield (Yp/s) ranged from 88-100% and 0.33-0.41?±?0.02 g/g, respectively, in all the hydrolysates tested. Hydrolysate after wet explosion at 185°C and 6 bar O2, composed of mixed sugars (glucose and xylose) and inhibitors such as acetate, HMF and furfural at concentrations of 3.2?±?0.1, 0.4 and 0.5 g/l, respectively, exhibited highest cell growth rate of 0.079 g/l/h and an ethanol yield of 0.39?±?0.02 g/g sugar converted. Scheffersomyces stipitis exhibited prolonged fermentation time on bagasse hydrolysate after wet explosion at 200°C and 6 bar O2 where the inhibitors concentration was further increased. Nonetheless, ethanol was produced up to 18.7?±?1.1 g/l resulting in a yield of 0.38?±?0.02 g/g after 82 h of fermentation. PMID:23895663

2013-01-01

133

Antioxidant Activities of Rapeseed Protein Hydrolysates  

Microsoft Academic Search

Rapeseed protein hydrolysates (RPH) were obtained by enzymatic hydrolysis of rapeseed protein using Alcalase 2.4 L FG. The\\u000a degree of hydrolysis (DH) of RPH was about 25% using pH-stat method. The antioxidant activities of RPH were investigated by\\u000a employing several in vitro assay, including the 1,1-diphenyl-2-picrylhydrazyl (DPPH)\\/superoxide\\/hydroxyl radical scavenging\\u000a assays, and reducing power assay. RPH showed scavenging activity against free radicals

Mu Pan; Tong S. Jiang; Jun L. Pan

134

Original article Lactose hydrolysing ability of sonicated cultures  

E-print Network

for hydrolysis in skim milk were slightly higher. Enzyme activity was not hindered in 30% lactose or 30% whey per products is the prevalence of "lactose intolerance", common among the adults of many of the world's ethnic groups could be improved with lac- tose-hydrolysed dairy products. Sources of the lactose-hydrolysing en

Paris-Sud XI, Université de

135

Role of collagen hydrolysate in bone and joint disease  

Microsoft Academic Search

Objectives: To review the current status of collagen hydrolysate in the treatment of osteoarthritis and osteoporosis. Methods: Review of past and current literature relative to collagen hydrolysate metabolism, and assessment of clinical investigations of therapeutic trials in osteoarthritis and osteoporosis. Results: Hydrolyzed gelatin products have long been used in pharmaceuticals and foods; these products are generally recognized as safe food

Roland W. Moskowitz

2000-01-01

136

[Antigenicity and allergenicity of hypoallergenic hydrolysate for infant nutrition].  

PubMed

The antigenicity/allergenicity of protein components in hypoallergenic formulae is altered by hydrolysis. Two different hydrolysate formulae, hydrolysate 1 = cow milk based; hydrolysate 2 = soya/beef collagen based, were investigated with respect to their specific IgG/IgE binding capacities using the sera of 41 healthy controls, 40 atopic and 12 cow milk allergic subjects. Furthermore, histamine liberation from basophils on incubation with milk proteins and the hydrolysates was measured in 5 healthy and 3 cow milk allergic individuals. Nearly all probands demonstrated specific IgG binding with hypoallergenic formulae. Anti-hydrolysate 1 IgG titres were higher than titres against hydrolysate 2 in the cow milk allergic and healthy populations. Nonhydrolyzed cow milk elicited IgE binding in all cow milk allergic sera. IgE-antibody for hydrolysate 2 could only be demonstrated in one atopic subject. Hydrolysate 1 showed binding capacity for the IgE-antibody of one atopic and 3/12 cow milk allergic patients. Histamine liberation followed in-vitro incubation with both hydrolysates in one out of 3 cow milk allergic subjects and two out of these cases following incubation to unprocessed cow milk protein. A decreased antigenicity/allergenicity can be demonstrated for the two hydrolysates investigated, however antigenic/allergenic reactivity is still present to some degree. Therefore, the therapeutic application of hypoallergenic formulae in patients with specific sensitization to cow milk should be based on the results of the above-mentioned in-vitro parameters and if necessary skin tests and oral challenges. PMID:1700289

Görtler, I; Urbanek, R

1990-09-01

137

Effect of lignocellulosic degradation compounds from steam explosion pretreatment on ethanol fermentation by thermotolerant yeast Kluyveromyces marxianus  

Microsoft Academic Search

The filtrate from steam-pretreated poplar was analyzed to identify degradation compounds. The effect of selected compounds\\u000a on growth and ethanolic fermentation of the thermotolerant yeast strain Kluyveromyces marxianus CECT 10875 was tested. Several fermentations on glucose medium, containing individual inhibitory compounds found in the hydrolysate,\\u000a were carried out. The degree of inhibition on yeast strain growth and ethanolic fermentation was

Jose Miguel Oliva; Felicia Sáez; Ignacio Ballesteros; Alberto González; Maria José Negro; Paloma Manzanares; Mercedes Ballesteros

2003-01-01

138

Characterization of isolated yeast growth response to methionine analogs.  

PubMed

Methionine is one of the first limiting amino acids in poultry nutrition. The use of methionine-rich natural feed ingredients, such as soybean meal or rapeseed meal may lead to negative environmental consequences. Amino acid supplementation leads to reduced use of protein-rich ingredients. The objectives of this study were isolation of potentially high content methionine-containing yeasts, quantification of methionine content in yeasts and their respective growth response to methionine analogs. Minimal medium was used as the selection medium and the isolation medium of methionine-producing yeasts from yeast collection and environmental samples, respectively. Two yeasts previously collected along with six additional strains isolated from Caucasian kefir grains, air-trapped, cantaloupe, and three soil samples could grow on minimal medium. Only two of the newly isolated strains, K1 and C1, grew in minimal medium supplied with either methionine analogs ethionine or norleucine at 0.5% (w/v). Based on large subunit rRNA sequences, these isolated strains were identified as Pichia udriavzevii/Issatchenkia orientalis. P. kudriavzevii/I. orentalis is a generally recognized as a safe organism. In addition, methionine produced by K1 and C1 yeast hydrolysate yielded 1.3 ± 0.01 and 1.1 ± 0.01 mg g(-1) dry cell. Yeast strain K1 may be suitable as a potential source of methionine for dietary supplements in organic poultry feed but may require growth conditions to further increase their methionine content. PMID:24007489

Saengkerdsub, Suwat; Lingbeck, Jody M; Wilkinson, Heather H; O'Bryan, Corliss A; Crandall, Philip G; Muthaiyan, Arunachalam; Biswas, Debabrata; Ricke, Steven C

2013-01-01

139

The influence of exogenous nutrients on the abundance of yeasts on the phylloplane of turfgrass.  

PubMed

Four experiments were conducted to assess the effect of foliar applications of various nutrient solutions on the phylloplane yeast community of tall fescue (Festuca arundinacea Schreb.). In the first three experiments, increasing concentrations of sucrose (2-16%), yeast extract (0.5-2.5%), and sucrose plus yeast extract (2.5-18.5% total) were applied and the yeast colony forming units (cfu) enumerated 14 h later by dilution plating. Significant positive linear relationships were observed between the number of yeast cfu and applications of both yeast extract and sucrose plus yeast extract. Foliar applications of sucrose alone had no significant effect on yeast community abundance, indicating that phylloplane yeasts of turfgrass are not limited by the amount or availability of carbohydrates. In the fourth experiment, five different solutions were applied to tall fescue to investigate the response of the yeast community to organic and inorganic nitrogen sources. Tryptone or yeast extract, both with considerable amino acid composition, significantly increased the yeast population, while yeast nitrogen base (with or without amino acids) and ammonium sulfate had no affect on yeast abundance. These results suggest that organic nitrogen stimulate yeast community growth and development on the phylloplane of tall fescue, while carbohydrates, inorganic nitrogen, and non-nitrogenous nutrients have little positive effect. PMID:17487523

Nix-Stohr, Shannon; Burpee, Leon L; Buck, James W

2008-01-01

140

Angiotensin I-converting enzyme-inhibitory peptides obtained from chicken collagen hydrolysate.  

PubMed

In this study, collagen extracted from chicken legs (which are the yellow keratin parts containing a nail) was hydrolyzed with various enzymes, and the angiotensin I-converting enzyme (ACE)-inhibitory activity of each hydrolysate was determined. The hydrolysate by treatment with an Aspergillus species-derived enzyme had the highest activity (IC 50 = 260 microg/mL). The fraction of this hydrolysate obtained by ultrafiltration with a molecular-weight cutoff of 3000 Da (low fraction) had a stronger activity (IC 50 = 130 microg/mL) than the fractionated one. This fraction was further fractionated by HPLC, and the peptides in the fraction with high ACE-inhibitory activity were identified. The amino acid sequences of the four peptides were identified using a protein sequencer. These peptides were synthesized to confirm their ACE-inhibitory activities; this showed that peptides with a Gly-Ala-Hyp-Gly-Leu-Hyp-Gly-Pro sequence had the highest activity (IC 50 = 29 microM). When the low fraction was administered to spontaneous hypertensive rats, a decrease in their blood pressure was observed after 2 h of administration, and a significant decrease in blood pressure (-50 mmHg) was observed after 6 h. Moreover, long-term administration studies indicated that the low fraction showed a significant suppression of increased blood pressure. PMID:18808143

Saiga, Ai; Iwai, Koji; Hayakawa, Toru; Takahata, Yoshihisa; Kitamura, Shiniich; Nishimura, Toshihide; Morimatsu, Fumiki

2008-10-22

141

Aspects of the cell growth of Candida guilliermondii in sugar cane bagasse hydrolysate.  

PubMed

In this work the behavior of the growth of Candida guilliermondii FTI 20037 in sugar cane bagasse hemicellulosic hydrolysate on various oxygen transfer rates was investigated. The yeast was able to grow and produced xylitol at different performance levels. At 1.0 vvm (volume of air per volume of medium per minute) the highest growth with 24.4 g/l was observed, but no xylitol was produced. At aeration rate of 0.5 vvm the growth was lower, but therefore slight amounts of xylitol (xylitol yield factor-Yp/s = 0.15 g/g) were observed. The lowest cell concentration (10.7 g/l) and the highest xylitol yield (Yp/s = 0.46 g/g) was observed when aeration was changed from 0.5 vvm to 0.05 vvm after 14 h. PMID:8663902

Molwitz, M; Silva, S S; Ribeiro, J D; Roberto, I C; Felipe, M G; Prata, A M; Mancilha, I M

1996-01-01

142

Yeast 14, 14531469 (1998) Expanding Yeast Knowledge Online  

E-print Network

YEAST Yeast 14, 1453­1469 (1998) Expanding Yeast Knowledge Online KARA DOLINSKI1 , CATHERINE A in the amount of new yeast genetics and molecular biology data. Efficient organization, presentation Sequences; Yeast Protein Database CONTENTS Introduction

Botstein, David

143

Optimisation of ultrasound-assisted extraction conditions for maximal recovery of active monacolins and removal of toxic citrinin from red yeast rice by a full factorial design coupled with response surface methodology.  

PubMed

This study optimised the ultrasound-assisted extraction (UAE) conditions to achieve maximal recovery of active monacolins with minimal contents of citrinin from red yeast rice (RYR). A central composite design after a full factorial design was utilised to examine the different UAE parameters. The studies revealed that HAc%, extraction time and EtOH% had significant influences on the recovery yield of monacolins, while HAc% and EtOH% were key factors for the elimination of citrinin. The resulting optimal conditions were as follows: ultrasound power of 250W, HAc% of 7.7%, RYR amount of 0.2g (solvent-to-solid ratio 40mL/g), extraction time of 50.7min, EtOH% of 57.2% and extraction temperature of 20°C. Under these conditions, at least 94.7% of monacolins was recovered and 87.7% of citrinin was removed from RYR. This optimised UAE condition was further evaluated for potential industrial application in manufacturing of RYR as pharmaceuticals and nutraceuticals. PMID:25306334

Zhou, Guisheng; Fu, Lei; Li, Xiaobo

2015-03-01

144

Antioxidation activities of low-molecular-weight gelatin hydrolysate isolated from the sea cucumber Stichopus japonicus  

Microsoft Academic Search

Gelatin extracted from the body wall of the sea cucumber (Stichopus japonicus) was hydrolyzed with flavourzyme. Low-molecular-weight gelatin hydrolysate (LMW-GH) of 700–1700 Da was produced using an\\u000a ultrafiltration membrane bioreactor system. Chemiluminescence analysis revealed that LMW-GH scavenges high free radicals in\\u000a a concentration-dependent manner; IC50 value for superoxide and hydroxyl radicals was 442 and 285 ?g mL?1, respectively. LMW-GH exhibited

Jingfeng Wang; Yuming Wang; Qingjuan Tang; Yi Wang; Yaoguang Chang; Qin Zhao; Changhu Xue

2010-01-01

145

Harnessing Genetic Diversity in Saccharomyces cerevisiae for Fermentation of Xylose in Hydrolysates of Alkaline Hydrogen Peroxide-Pretreated Biomass  

PubMed Central

The fermentation of lignocellulose-derived sugars, particularly xylose, into ethanol by the yeast Saccharomyces cerevisiae is known to be inhibited by compounds produced during feedstock pretreatment. We devised a strategy that combined chemical profiling of pretreated feedstocks, high-throughput phenotyping of genetically diverse S. cerevisiae strains isolated from a range of ecological niches, and directed engineering and evolution against identified inhibitors to produce strains with improved fermentation properties. We identified and quantified for the first time the major inhibitory compounds in alkaline hydrogen peroxide (AHP)-pretreated lignocellulosic hydrolysates, including Na+, acetate, and p-coumaric (pCA) and ferulic (FA) acids. By phenotyping these yeast strains for their abilities to grow in the presence of these AHP inhibitors, one heterozygous diploid strain tolerant to all four inhibitors was selected, engineered for xylose metabolism, and then allowed to evolve on xylose with increasing amounts of pCA and FA. After only 149 generations, one evolved isolate, GLBRCY87, exhibited faster xylose uptake rates in both laboratory media and AHP switchgrass hydrolysate than its ancestral GLBRCY73 strain and completely converted 115 g/liter of total sugars in undetoxified AHP hydrolysate into more than 40 g/liter ethanol. Strikingly, genome sequencing revealed that during the evolution from GLBRCY73, the GLBRCY87 strain acquired the conversion of heterozygous to homozygous alleles in chromosome VII and amplification of chromosome XIV. Our approach highlights that simultaneous selection on xylose and pCA or FA with a wild S. cerevisiae strain containing inherent tolerance to AHP pretreatment inhibitors has potential for rapid evolution of robust properties in lignocellulosic biofuel production. PMID:24212571

Liu, Tongjun; Parreiras, Lucas S.; Williams, Daniel L.; Wohlbach, Dana J.; Bice, Benjamin D.; Ong, Irene M.; Breuer, Rebecca J.; Qin, Li; Busalacchi, Donald; Deshpande, Shweta; Daum, Chris; Gasch, Audrey P.

2014-01-01

146

Harnessing genetic diversity in Saccharomyces cerevisiae for fermentation of xylose in hydrolysates of alkaline hydrogen peroxide-pretreated biomass.  

PubMed

The fermentation of lignocellulose-derived sugars, particularly xylose, into ethanol by the yeast Saccharomyces cerevisiae is known to be inhibited by compounds produced during feedstock pretreatment. We devised a strategy that combined chemical profiling of pretreated feedstocks, high-throughput phenotyping of genetically diverse S. cerevisiae strains isolated from a range of ecological niches, and directed engineering and evolution against identified inhibitors to produce strains with improved fermentation properties. We identified and quantified for the first time the major inhibitory compounds in alkaline hydrogen peroxide (AHP)-pretreated lignocellulosic hydrolysates, including Na(+), acetate, and p-coumaric (pCA) and ferulic (FA) acids. By phenotyping these yeast strains for their abilities to grow in the presence of these AHP inhibitors, one heterozygous diploid strain tolerant to all four inhibitors was selected, engineered for xylose metabolism, and then allowed to evolve on xylose with increasing amounts of pCA and FA. After only 149 generations, one evolved isolate, GLBRCY87, exhibited faster xylose uptake rates in both laboratory media and AHP switchgrass hydrolysate than its ancestral GLBRCY73 strain and completely converted 115 g/liter of total sugars in undetoxified AHP hydrolysate into more than 40 g/liter ethanol. Strikingly, genome sequencing revealed that during the evolution from GLBRCY73, the GLBRCY87 strain acquired the conversion of heterozygous to homozygous alleles in chromosome VII and amplification of chromosome XIV. Our approach highlights that simultaneous selection on xylose and pCA or FA with a wild S. cerevisiae strain containing inherent tolerance to AHP pretreatment inhibitors has potential for rapid evolution of robust properties in lignocellulosic biofuel production. PMID:24212571

Sato, Trey K; Liu, Tongjun; Parreiras, Lucas S; Williams, Daniel L; Wohlbach, Dana J; Bice, Benjamin D; Ong, Irene M; Breuer, Rebecca J; Qin, Li; Busalacchi, Donald; Deshpande, Shweta; Daum, Chris; Gasch, Audrey P; Hodge, David B

2014-01-01

147

Engineering and Two-Stage Evolution of a Lignocellulosic Hydrolysate-Tolerant Saccharomyces cerevisiae Strain for Anaerobic Fermentation of Xylose from AFEX Pretreated Corn Stover  

PubMed Central

The inability of the yeast Saccharomyces cerevisiae to ferment xylose effectively under anaerobic conditions is a major barrier to economical production of lignocellulosic biofuels. Although genetic approaches have enabled engineering of S. cerevisiae to convert xylose efficiently into ethanol in defined lab medium, few strains are able to ferment xylose from lignocellulosic hydrolysates in the absence of oxygen. This limited xylose conversion is believed to result from small molecules generated during biomass pretreatment and hydrolysis, which induce cellular stress and impair metabolism. Here, we describe the development of a xylose-fermenting S. cerevisiae strain with tolerance to a range of pretreated and hydrolyzed lignocellulose, including Ammonia Fiber Expansion (AFEX)-pretreated corn stover hydrolysate (ACSH). We genetically engineered a hydrolysate-resistant yeast strain with bacterial xylose isomerase and then applied two separate stages of aerobic and anaerobic directed evolution. The emergent S. cerevisiae strain rapidly converted xylose from lab medium and ACSH to ethanol under strict anaerobic conditions. Metabolomic, genetic and biochemical analyses suggested that a missense mutation in GRE3, which was acquired during the anaerobic evolution, contributed toward improved xylose conversion by reducing intracellular production of xylitol, an inhibitor of xylose isomerase. These results validate our combinatorial approach, which utilized phenotypic strain selection, rational engineering and directed evolution for the generation of a robust S. cerevisiae strain with the ability to ferment xylose anaerobically from ACSH. PMID:25222864

Parreiras, Lucas S.; Breuer, Rebecca J.; Avanasi Narasimhan, Ragothaman; Higbee, Alan J.; La Reau, Alex; Tremaine, Mary; Qin, Li; Willis, Laura B.; Bice, Benjamin D.; Bonfert, Brandi L.; Pinhancos, Rebeca C.; Balloon, Allison J.; Uppugundla, Nirmal; Liu, Tongjun; Li, Chenlin; Tanjore, Deepti; Ong, Irene M.; Li, Haibo; Pohlmann, Edward L.; Serate, Jose; Withers, Sydnor T.; Simmons, Blake A.; Hodge, David B.; Westphall, Michael S.; Coon, Joshua J.; Dale, Bruce E.; Balan, Venkatesh; Keating, David H.; Zhang, Yaoping; Landick, Robert; Gasch, Audrey P.; Sato, Trey K.

2014-01-01

148

Determination of Mustard and Thiodiglycol in Mustard Hydrolysate.  

National Technical Information Service (NTIS)

The mustard stored at the Defence Research Establishment Suffield was disposed of by hydrolysis during the 1970's. Samples of the liquid and sludge hydrolysate were analysed by gas chromatography with flame ionization and mass spectral detection for resid...

P. A. D'Agostino, L. R. Provost

1984-01-01

149

Antioxidant Peptides from the Protein Hydrolysates of Conus betulinus  

Microsoft Academic Search

The current study aims at the isolation and characterization of the peptides, believed to have antioxidant activity, from\\u000a Conus betulinus by using different types of enzymes. The body and viscera of C. betulinus were treated with three enzymes viz. trypsin, pepsin and papain to obtain peptide hydrolysates. The activities of the hydrolysates\\u000a were analyzed by DPPH and hydroxyl radical assay

R. A. NazeerT; T. S. Srividhya

2011-01-01

150

Production of ethanol from soybean hull hydrolysate by osmotolerant Candida guilliermondii NRRL Y-2075.  

PubMed

In this research, we studied the use of soybean hull hydrolysate (SHH) as a substrate for ethanol and xylitol production using an osmotolerant strain of Candida guilliermondii. The best acid hydrolysis of soybean hull achieved a recovery of 85 and 62% of xylose and mannose, respectively. Among detoxification treatments, activated charcoal 10% (w/v) showed the best results. Kinetic parameters obtained from the cultivation on four-fold concentrated SHH have shown that the osmotic pressure of this medium is higher than that supported by most osmophilic yeasts, revealing the osmotolerant characteristic of C. guilliermondii NRRL Y-2075. When cultivations were carried out on two times concentrated SHH, we obtained high yields of ethanol production, showing the prospect of SHH as a candidate for this biofuel production. Although xylose was present in high concentrations, no xylitol was produced, probably due to the presence of furfural acting as external electron acceptor or some varying cofactor preference of xylose reductase in this yeast strain. PMID:17706417

Schirmer-Michel, Angela Cristina; Flôres, Simone Hickmann; Hertz, Plinho Francisco; Matos, Gilvane Souza; Ayub, Marco Antonio Záchia

2008-05-01

151

Collagen hydrolysate inhibits zymosan-induced inflammation.  

PubMed

During the past years, evidence accumulated showing that glycine comprises anti-inflammatory activities. These effects occur, at least in part, via the activation of glycine-gated chloride channels (GlyR). Glycine is one of the major structural units of collagen, making up about 30% of the amino acids. This study aims to investigate the anti-inflammatory potential of collagen hydrolysate (CH) using the zymosan-induced ear-skin inflammation mouse model. After oral intake of 12.5, 25 or 50 mg CH the plasma levels of glycine increased in a concentration-dependent manner. CH was able to counteract zymosan-induced ear-skin inflammation locally (ear swelling) as well as systemically (IL-6 production by lipopolysaccharide (LPS)-stimulated whole blood cells). The LPS-stimulated IL-6 production in whole blood correlated positively with the ear swelling response. This correlation was abolished by strychnine (a glycine receptor antagonist), indicating the involvement of GlyR. Collectively, these data show that CH is able to modulate inflammatory responses both locally as well as systemically. This effect might be constituted by inhibiting pro-inflammatory cytokine production via GlyR. PMID:23788175

Hartog, Anita; Cozijnsen, Miranda; de Vrij, Gerrit; Garssen, Johan

2013-07-01

152

Amylase binding to starch granules under hydrolysing and non-hydrolysing conditions.  

PubMed

Although considerable information is available about amylolysis rate, extent and pattern of granular starches, the underlying mechanisms of enzyme action and interactions are not fully understood, partly due to the lack of direct visualisation of enzyme binding and subsequent hydrolysis of starch granules. In the present study, ?-amylase (AA) from porcine pancreas was labelled with either fluorescein isothiocyanate (FITC) or tetramethylrhodamine isothiocyanate (TRITC) fluorescent dye with maintenance of significant enzyme activity. The binding of FITC/TRITC-AA conjugate to the surface and interior of granules was studied under both non-hydrolysing (0 °C) and hydrolysing (37 °C) conditions with confocal microscopy. It was observed that enzyme binding to maize starch granules under both conditions was more homogenous compared with potato starch. Enzyme molecules appear to preferentially bind to the granules or part of granules that are more susceptible to enzymic degradation. The specificity is such that fresh enzyme added after a certain time of incubation binds at the same location as previously bound enzyme. By visualising the enzyme location during binding and hydrolysis, detailed information is provided regarding the heterogeneity of granular starch digestion. PMID:25256464

Dhital, Sushil; Warren, Frederick J; Zhang, Bin; Gidley, Michael J

2014-11-26

153

Effect of collagen hydrolysate on chondrocyte-seeded agarose constructs.  

PubMed

The mechanical properties of engineered cartilage are strongly dependent on collagen content, but the collagen to glycosaminoglycan ratio in engineered cartilage is often much lower than that of the native tissue. Therefore culture medium supplements which increase collagen production by chondrocytes are of interest. It had previously been reported that collagen hydrolysate stimulated type II collagen biosynthesis in short-term, high density monolayer chondrocyte cultures. It was hypothesized that collagen hydrolysate added to the culture medium of three dimensional chondrocyte-agarose constructs would enhance their mechanical properties. Porcine articular chondrocytes were embedded in 2% agarose and cultured for up to 6 weeks with and without 1 mg/ml collagen hydrolysate. The instantaneous compressive modulus and equilibrium compressive modulus were significantly lower in the collagen hydrolysate-treated constructs, consistent with the finding of lower collagen and GAG content. Contrary to our hypothesis, our results indicate that 1 mg/ml collagen hydrolysate may actually inhibit macromolecule biosynthesis and be detrimental to the mechanical properties of long term chondrocyte-agarose constructs. PMID:20231793

Elder, Steven H; Borazjani, Ali

2009-01-01

154

Components of the yeast spindle and spindle pole body  

Microsoft Academic Search

Yeast spindle pole bodies (SPBs) with at- tached nuclear microtubules were enriched ,x,600-fold from yeast cell extracts. 14 mAbs prepared against this enriched SPB fraction define at least three components of the SPB and spindle. Immunofluorescent staining of yeast cells showed that throughout the cell cycle two of the components (110 and 90 kD) were localized ex- clusively to the

Michael P. Rout; John V. Kilmartin

1990-01-01

155

[Process development for continuous ethanol fermentation by the flocculating yeast under stillage backset conditions].  

PubMed

Propionic acid, a major inhibitor to yeast cells, was accumulated during continuous ethanol fermentation from corn meal hydrolysate by the flocculating yeast under stillage backset conditions. Based on its inhibition mechanism in yeast cells, strategies were developed for alleviating this effect. Firstly, high temperature processes such as medium sterilization generated more propionic acid, which should be avoided. Propionic acid was reduced significantly during ethanol fermentation without medium sterilization, and concentrations of biomass and ethanol increased by 59.3% and 7.4%, respectively. Secondly, the running time of stillage backset should be controlled so that propionic acid accumulated would be lower than its half inhibition concentration IC50 (40 mmol/L). Finally, because low pH augmented propionic acid inhibition in yeast cells, a higher pH of 5.5 was validated to be suitable for ethanol fermentation under the stillage backset condition. PMID:24941752

Zi, Lihan; Liu, Chenguang; Bai, Fengwu

2014-02-01

156

Yeasts associated with fresh and frozen pulps of Brazilian tropical fruits.  

PubMed

The occurrence of yeasts on ripe fruits and frozen pulps of pitanga (Eugenia uniflora L), mangaba (Hancornia speciosa Gom.), umbu (Spondias tuberosa Avr. Cam.), and acerola (Malpighia glaba L) was verified. The incidence of proteolytic, pectinolytic, and mycocinogenic yeasts on these communities was also determined. A total of 480 colonies was isolated and grouped in 405 different strains. These corresponded to 42 ascomycetous and 28 basidiomycetous species. Candida sorbosivorans, Pseudozyma antarctica, C. spandovensis-like, C. spandovensis, Kloeckera apis, C. parapsilosis, Rhodotorula graminis, Kluyveromyces marxianus, Cryptococcus laurentii, Metchnikowia sp (isolated only from pitanga ripe fruits), Issatchenkia occidentalis and C. krusei (isolated only from mangaba frozen pulps), were the most frequent species. The yeast communities from pitanga ripe fruits exhibited the highest frequency of species, followed by communities from acerola ripe fruits and mangaba frozen pulps. Yeast communities from frozen pulp and ripe fruits of umbu had the lowest number of species. Except the yeasts from pitanga, yeast communities from frozen pulp exhibited higher number of yeasts than ripe fruit communities. Mycocinogenic yeasts were found in all of the substrates studied except in communities from umbu ripe fruits and pitanga frozen pulps. Most of the yeasts found to produce mycocins were basidiomycetes and included P. antarctica, Cryptococcus albidus, C. bhutanensis-like, R. graminis and R. mucilaginosa-like from pitanga ripe fruits as well as black yeasts from pitanga and acerola ripe fruits. The umbu frozen pulps community had the highest frequency of proteolytic species. Yeasts able to hydrolyse casein at pH 5.0 represented 38.5% of the species isolated. Thirty-seven percent of yeast isolates were able to hydrolyse casein at pH 7.0. Pectinolytic yeasts were found in all of the communities studied, excepted for those of umbu frozen pulps. The highest frequency of pectinolytic activity was found in mangaba frozen pulp communities. Around 30% of all isolates produced pectinases. The ability to split arbutin was observed in all communities ranging from 8% in yeasts from pitanga frozen pulps to 40.6% in acerola ripe fruit communities. Among 432 species tested, 125 were active for beta-glucosidase production, and Kloeckera apis, P. antarctica, C. sorbosivorans, and C. spandovensis-like were the most active species. PMID:12353886

Trindade, Rita C; Resende, Maria Aparecida; Silva, Claudia M; Rosa, Carlos A

2002-08-01

157

Protein expression-yeast.  

PubMed

Yeast is an excellent system for the expression of recombinant eukaryotic proteins. Both endogenous and heterologous proteins can be overexpressed in yeast (Phan et al., 2001; Ton and Rao, 2004). Because yeast is easy to manipulate genetically, a strain can be optimized for the expression of a specific protein. Many eukaryotic proteins contain posttranslational modifications that can be performed in yeast but not in bacterial expression systems. In comparison with mammalian cell culture expression systems, growing yeast is both faster and less expensive, and large-scale cultures can be performed using fermentation. While several different yeast expression systems exist, this chapter focuses on the budding yeast Saccharomyces cerevisiae and will briefly describe some options to consider when selecting vectors and tags to be used for protein expression. Throughout this chapter, the expression and purification of yeast eIF3 is shown as an example alongside a general scheme outline. PMID:24423273

Nielsen, Klaus H

2014-01-01

158

Yeast Based Sensors  

NASA Astrophysics Data System (ADS)

Since the first microbial cell sensor was studied by Karube et al. in 1977, many types of yeast based sensors have been developed as analytical tools. Yeasts are known as facultative anaerobes. Facultative anaerobes can survive in both aerobic and anaerobic conditions. The yeast based sensor consisted of a DO electrode and an immobilized omnivorous yeast. In yeast based sensor development, many kinds of yeast have been employed by applying their characteristics to adapt to the analyte. For example, Trichosporon cutaneum was used to estimate organic pollution in industrial wastewater. Yeast based sensors are suitable for online control of biochemical processes and for environmental monitoring. In this review, principles and applications of yeast based sensors are summarized.

Shimomura-Shimizu, Mifumi; Karube, Isao

159

Production of enzymatic protein hydrolysates from freshwater catfish (Clarias batrachus)  

NASA Astrophysics Data System (ADS)

Fish protein hydrolysate (FPH) was prepared from freshwater catfish (Clarias batrachus) by using Alcalase® 2.4L and Papain. The effect of hydrolysis time (30, 60, 120, 180 min) with enzyme concentration of 1% (v/w substrate); pH = 8.0, 7.0 was studied to determine the degree of hydrolysis (DH), peptide content, proximate composition and amino acid profile. Results showed that the highest DH of Alcalase and Papain FPH were 58.79% and 53.48% after 180 min at 55°C incubation respectively. The peptide content of both FPH increased as hydrolysis time increases. FPH showed higher crude protein content and lower fat, moisture and ash content compared to raw catfish. The major amino acids of both hydrolysates were Glu, Lys and Asp. Content of essential amino acids of Alcalase and Papain hydrolysates were 44.05% and 43.31% respectively.

Seniman, Maizatul Sarah Md; Yusop, Salma Mohamad; Babji, Abdul Salam

2014-09-01

160

CLONTECHInnovative Yeast Protocols Handbook  

E-print Network

CLONTECHInnovative Tools to Accelerate Discovery Yeast Protocols Handbook PT3024-1 (PR13103 FOR RESEARCH USE ONLY #12;Yeast Protocols Handbook CLONTECH Laboratories, Inc. www.clontech.com Protocol # PT3024-1 2 Version # PR13103 I. Introduction 4 II. Introduction to Yeast Promoters 5 III. Culturing

Erickson, F. Les

161

[Yeasts contaminating salmon roe].  

PubMed

Quantitative and species compositions of yeast contaminating eggs, fry and fingerlings of Salmo gairdneri Rich under artificial breeding have been studied. Prevalence of species of genera Candida, Rhodotorula, Cryptococcus and Debaryomyces is noted. Yeast isolated from perished eggs and sick fry do not possess pathogenic properties. Certain strains of yeast make stimulating effect on the studied microorganisms. PMID:8983527

Nagornaia, S S; Ignatova, E A; Isaeva, N M; Davydov, O N; Podgorski?, V S

1996-01-01

162

YEAST GENETICS Fred Winston  

E-print Network

YEAST GENETICS Fred Winston 7.1 Introduction Key Concepts · Genetic studies of the yeast. The yeast Saccharomyces cerevisiae is an ideal experimental organism. It is a microorganism that has a fast rate of growth, with a generation time of only ninety minutes under optimal conditions. Genetic methods

Winston, Fred

163

Characterization of tyrosine-rich Antheraea pernyi silk fibroin hydrolysate.  

PubMed

Antheraea pernyi silk fibroin (SF) hydrolysate were characterized using UV-VIS spectrometer, amino acid composition and heavy metal contents to explore its potential sources for food or cosmetic additives. The hydrolyzed A. pernyi SF was separated into two parts: (a) SFA, alanine-rich fraction and (b) SFB, tyrosine-rich fraction. SFB exhibited strong absorption peaks at 210 and 280 nm due to the presence of the tyrosine. Heavy metal analysis showed that arsenic and mercury did not detect. Other heavy metals, which includes lead, cadmium, etc., were recorded only a trace amount. Therefore, A. pernyi SF hydrolysate could be safely used as sources of food, cosmetic and pharmaceuticals. PMID:20937302

Lee, Kwang-gill; Kweon, HaeYong; Yeo, Joo-hong; Woo, SoonOk; Han, SangMi; Kim, Jong-Ho

2011-01-01

164

Evaluation of sorghum straw hemicellulosic hydrolysate for biotechnological production of xylitol by Candida guilliermondii  

PubMed Central

A preliminary study on xylitol production by Candida guilliermondii in sorghum straw hemicellulosic hydrolysate was performed. Hydrolysate had high xylose content and inhibitors concentrations did not exceed the commonly found values in other hemicellulosic hydrolysates. The highest xylitol yield (0.44 g/g) and productivity (0.19 g/Lh) were verified after 72 hours. PMID:24031733

Sene, L.; Arruda, P.V.; Oliveira, S.M.M.; Felipe, M.G.A.

2011-01-01

165

Concentrations of Trace Elements in Extensively Hydrolysed Infant Formulae and Their Estimated Daily Intakes  

Microsoft Academic Search

The 18 trace elements Ba, Be, Bi, Cd, Co, Cs, Cu, La, Li, Mn, Mo, Pb, Rb, Sb, Sn, Sr, Tl, and Zn were determined in three extensively hydrolysed formulae by inductively coupled plasma mass spectrometry. Two formulae were whey hydrolysates, whereas one was based on soy-bovine collagen hydrolysate. Two skim milk powder reference materials, analyzed to ensure the analytical

M. Krachler; E. Rossipal; G. Chan; J. Kerner; S. Kharb; R. Kakkar

2000-01-01

166

Optimization of antioxidant activity by response surface methodology in hydrolysates of jellyfish (Rhopilema esculentum) umbrella collagen*  

PubMed Central

To optimize the hydrolysis conditions to prepare hydrolysates of jellyfish umbrella collagen with the highest hydroxyl radical scavenging activity, collagen extracted from jellyfish umbrella was hydrolyzed with trypsin, and response surface methodology (RSM) was applied. The optimum conditions obtained from experiments were pH 7.75, temperature (T) 48.77 °C, and enzyme-to-substrate ratio ([E]/[S]) 3.50%. The analysis of variance in RSM showed that pH and [E]/[S] were important factors that significantly affected the process (P<0.05 and P<0.01, respectively). The hydrolysates of jellyfish umbrella collagen were fractionated by high performance liquid chromatography (HPLC), and three fractions (HF-1>3000 Da, 1000 Da

Zhuang, Yong-liang; Zhao, Xue; Li, Ba-fang

2009-01-01

167

Effect of cooking temperature on the crystallinity of acid hydrolysed-oil palm cellulose  

NASA Astrophysics Data System (ADS)

In this research, we studied the effect of acid hydrolysis temperature on the crystallinity of cellulose produced from empty fruit bunch (EFB). The hydrolysis temperature was studied from 120 to 140 °C at a fixed time and sulfuric acid, H2SO4 concentration which were 1 h and 1% (v/v) respectively. X-ray diffractometry (XRD) was carried out to measure the crystallinity of cellulose produced at varying hydrolysis temperatures. During hydrolysis, the amorphous region of ?-cellulose was removed and the crystalline region was obtained. Percentage of crystallinity (CrI) for acid hydrolysed cellulose at 120, 130 and 140 °C were 54.21, 50.59 and 50.55 % respectively. Morphological studies using scanning electron microscope (SEM) showed that acid hydrolysis defibrilised to microfibrils in ?-cellulose. The extraction process to produce ?-cellulose has also been successfully carried out as the impurities at the outer surface, lignin and hemicellulose were removed. These findings were supported by the disappearance of peaks at 1732, 1512 and 1243 cm-1 on Fourier Transform infrared (FTIR) spectrum of ?-cellulose. Similar peaks were identified in both the commercial microcrystalline cellulose (C-MCC) and acid hydrolysed cellulose (H-EFB), indicating the effectiveness of heat-catalysed acid hydrolysis.

Kuthi, Fatin Afifah Binti Ahmad; Badri, Khairiah Haji

2014-09-01

168

Effect of organic acids on the growth and lipid accumulation of oleaginous yeast Trichosporon fermentans  

PubMed Central

Background Microbial lipids have drawn increasing attention in recent years as promising raw materials for biodiesel production, and the use of lignocellulosic hydrolysates as carbon sources seems to be a feasible strategy for cost-effective lipid fermentation with oleaginous microorganisms on a large scale. During the hydrolysis of lignocellulosic materials with dilute acid, however, various kinds of inhibitors, especially large amounts of organic acids, will be produced, which substantially decrease the fermentability of lignocellulosic hydrolysates. To overcome the inhibitory effects of organic acids, it is critical to understand their impact on the growth and lipid accumulation of oleaginous microorganisms. Results In our present work, we investigated for the first time the effect of ten representative organic acids in lignocellulosic hydrolysates on the growth and lipid accumulation of oleaginous yeast Trichosporon fermentans cells. In contrast to previous reports, we found that the toxicity of the organic acids to the cells was not directly related to their hydrophobicity. It is worth noting that most organic acids tested were less toxic than aldehydes to the cells, and some could even stimulate the growth and lipid accumulation at a low concentration. Unlike aldehydes, most binary combinations of organic acids exerted no synergistic inhibitory effects on lipid production. The presence of organic acids decelerated the consumption of glucose, whereas it influenced the utilization of xylose in a different and complicated way. In addition, all the organic acids tested, except furoic acid, inhibited the malic activity of T. fermentans. Furthermore, the inhibition of organic acids on cell growth was dependent more on inoculum size, temperature and initial pH than on lipid content. Conclusions This work provides some meaningful information about the effect of organic acid in lignocellulosic hydrolysates on the lipid production of oleaginous yeast, which is helpful for optimization of biomass hydrolysis processes, detoxified pretreatment of hydrolysates and lipid production using lignocellulosic materials. PMID:22260291

2012-01-01

169

Effect of the oxygen transfer coefficient on xylitol production from sugarcane bagasse hydrolysate by continuous stirred-tank reactor fermentation.  

PubMed

The effect of the oxygen transfer coefficient on the production of xylitol by bioconversion of xylose present in sugarcane bagasse hemicellulosic hydrolysate using the yeast Candida guilliermondii was investigated. Continuous cultivation was carried out in a 1.25-L fermentor at 30 degrees C, pH 5.5, 300 rpm, and a dilution rate of 0.03/h, using oxygen transfer coefficients of 10, 20, and 30/h. The results showed that the microbial xylitol production (11 g/L) increased by 108% with the decrease in the oxygen volumetric transfer coefficient from 30 to 20/h. The maximum values of xylitol productivity (0.7 g/[L.h]) and yield (0.58 g/g) were obtained akLa 20/h. PMID:10849823

Martínez, E A; Silva, S S; Felipe, M G

2000-01-01

170

Characterization of casein hydrolysates derived from enzymatic hydrolysis  

PubMed Central

Background Casein is the main proteinaceous component of milk and has made us interest due to its wide applications in the food, drug, and cosmetic industries as well as to its importance as an investigation material for elucidating essential questions regarding the protein chemistry. Enzymatic hydrolysis is an important method commonly used in the modification of protein structure in order to enhance the functional properties of proteins. The relationship between enzymatic hydrolysis and structure change of casein need to make more study. Results During hydrolysis, degree of hydrolysis in the casein hydrolysates increased rapidly in the initial 20 minutes, reached a plateau after 45 minutes, and then kept relative constant for the rest of the hydrolysis. The relative percentage of the released peptides with molecular weight of over 50 kD significantly decreased with hydrolyzation, while those with MW of 30–50 kD and below 20 kD increased significantly. The contents of a-helix and ?-turn in the hydrolysates increased compared to the original casein. Moreover, the molecular flexibilities of the casein hydrolysates, estimated by the ratio of ?-helix to ?-structure, were lower than that of original casein protein. Conclusions The significant changes in molecular weight distribution and structure characteristics of casein hydrolysates were found compared to the control sample. This change should be the basis of enhancement of functional properties. PMID:23556455

2013-01-01

171

Isolation of microorganisms for biological detoxification of lignocellulosic hydrolysates  

Microsoft Academic Search

Acid pretreatment of lignocellulosic biomass releases furan and phenolic compounds, which are toxic to microorganisms used for subsequent fermentation. In this study, we isolated new microorganisms for depletion of inhibitors in lignocellulosic acid hydrolysates. A sequential enrichment strategy was used to isolate microorganisms from soil. Selection was carried out in a defined mineral medium containing a mixture of ferulic acid

M. J. López; N. N. Nichols; B. S. Dien; J. Moreno; R. J. Bothast

2004-01-01

172

Evaluation of hexose and pentose in pre-cultivation of Candida guilliermondii on the key enzymes for xylitol production in sugarcane hemicellulosic hydrolysate.  

PubMed

The evaluation of hexose and pentose in pre-cultivation of Candida guilliermondii FTI 20037 yeast on xylose reductase (XR) and xylitol dehydrogenase (XDH) enzymes activities was performed during fermentation in sugarcane bagasse hemicellulosic hydrolysate. The xylitol production was evaluated by using cells previously growth in 30.0 gl(-1) xylose, 30.0 gl(-1) glucose and in both sugars mixture (30.0 gl(-1) xylose and 2.0 gl(-1) glucose). The vacuum evaporated hydrolysate (80 gl(-1)) was detoxificated by ion exchange resin (A-860S; A500PS and C-150-Purolite®). The total phenolic compounds and acetic acid were 93.0 and 64.9%, respectively, removed by the resin hydrolysate treatment. All experiments were carried out in Erlenmeyer flasks at 200 rpm, 30°C. The maximum XR (0.618 Umg (Prot) (-1)) and XDH (0.783 Umg (Prot) (-1)) enzymes activities was obtained using inoculum previously growth in both sugars mixture. The highest cell concentration (10.6 gl(-1)) was obtained with inoculum pre-cultivated in the glucose. However, the xylitol yield and xylitol volumetric productivity were favored using the xylose as carbon source. In this case, it was observed maximum xylose (81%) and acetic acid (100%) consumption. It is very important to point out that maximum enzymatic activities were obtained when the mixture of sugars was used as carbon source of inoculum, while the highest fermentative parameters were obtained when xylose was used. PMID:20683763

de Arruda, Priscila Vaz; Rodrigues, Rita de Cássia Lacerda Brambilla; da Silva, Débora Danielle Virgínio; Felipe, Maria das Graças de Almeida

2011-07-01

173

Myrosinase hydrolysates of Brassica oleraceae L. var. italica reduce the risk of colon cancer.  

PubMed

By means of liquid chromatography-electrospray ionization (LC-ESI) mass spectrometry two glucosinolates, glucoiberin and 3-hydroxy,4(?-L-rhamnopyranosyloxy) benzyl glucosinolate, were identified in the aqueous extract of Brassica oleraceae L var. italica. Further, two compounds were isolated after enzymatic hydrolysis of the aqueous extract by myrosinase, one of them was identified as 4-vinyl-3-pyrazolidinone. The second compound (sulphoraphane) 1-isothiocyanate-4-methyl-sulphinyl butane, converted to the most stable form of thiourea (sulphoraphane thiourea). The crude extract (80% alcohol extract) of broccoli florets was examined for cytotoxic activity against different human cancer cell lines, it showed good inhibition of colon cancer (IC(50) 3.88 µg/mL). On the other hand each of the successive extracts (petroleum ether, chloroform, ethyl acetate and ethanol) showed no significant cytotoxic activity. When myrosinase hydrolysate was tested for cytotoxic activity on the colon cancer cell line it showed very high activity - 95% lethality up to 0.78 µg/mL. PMID:22076869

Hashem, F A; Motawea, H; El-Shabrawy, A E; Shaker, K; El-Sherbini, S

2012-05-01

174

Isolation and characterization of ethanol tolerant yeast strains.  

PubMed

Yeast strains are commonly associated with sugar rich environments. Various fruit samples were selected as source for isolating yeast cells. The isolated cultures were identified at Genus level by colony morphology, biochemical characteristics and cell morphological characters. An attempt has been made to check the viability of yeast cells under different concentrations of ethanol. Ethanol tolerance of each strain was studied by allowing the yeast to grow in liquid YEPD (Yeast Extract Peptone Dextrose) medium having different concentrations of ethanol. A total of fifteen yeast strains isolated from different samples were used for the study. Seven strains of Saccharomyces cerevisiae obtained from different fruit sources were screened for ethanol tolerance. The results obtained in this study show a range of tolerance levels between 7%-12% in all the stains. Further, the cluster analysis based on 22 RAPD (Random Amplified polymorphic DNA) bands revealed polymorphisms in these seven Saccharomyces strains. PMID:23750092

Tikka, Chiranjeevi; Osuru, Hari Prasad; Atluri, Navya; Raghavulu, Praveen Chakravarthi Veera; Yellapu, Nanda Kumar; Mannur, Ismail Shaik; Prasad, Uppu Venkateswara; Aluru, Sudheer; K, Narasimha Varma; Bhaskar, Matcha

2013-01-01

175

Antioxidation activities of low-molecular-weight gelatin hydrolysate isolated from the sea cucumber Stichopus japonicus  

NASA Astrophysics Data System (ADS)

Gelatin extracted from the body wall of the sea cucumber ( Stichopus japonicus) was hydrolyzed with flavourzyme. Low-molecular-weight gelatin hydrolysate (LMW-GH) of 700-1700 Da was produced using an ultrafiltration membrane bioreactor system. Chemiluminescence analysis revealed that LMW-GH scavenges high free radicals in a concentration-dependent manner; IC50 value for superoxide and hydroxyl radicals was 442 and 285 ?g mL-1, respectively. LMW-GH exhibited excellent inhibitory characteristics against melanin synthesis and tyrosinase activity in B16 cells. Furthermore, LMW-GH notably increased intracellular glutathione (GSH), which in turn suppressed melanogenesis. LMW-GH performs antioxidation activity, holding the potential of being used as a valuable ingredient in function foods, cosmetics and pharmaceuticals or nutriceuticals.

Wang, Jingfeng; Wang, Yuming; Tang, Qingjuan; Wang, Yi; Chang, Yaoguang; Zhao, Qin; Xue, Changhu

2010-03-01

176

Proteomic Research Reveals the Stress Response and Detoxification of Yeast to Combined Inhibitors  

PubMed Central

The tolerant mechanism of yeast to the combination of three inhibitors (furfural, phenol and acetic acid) was investigated using 2-DE combined with MALDI-TOF/TOF-MS. The stress response and detoxification related proteins (e.g., Ahp1p, Hsp26p) were expressed higher in the tolerant yeast than in the parental yeast. The expressions of most nitrogen metabolism related proteins (e.g. Gdh1p, Met1p) were higher in the parental yeast, indicating that the tolerant yeast decreases its nitrogen metabolism rate to reserve energy, and possesses high resistance to the stress of combined inhibitors. Furthermore, upon exposure to the inhibitors, the proteins related to protein folding, degradation and translation (e.g., Ssc1p, Ubp14p, Efb1p) were all significantly affected, and the oxidative stress related proteins (e.g., Ahp1p, Grx1p) were increased. Knockdown of genes related to the oxidative stress and unfolded protein response (Grx1, Gre2, Asc1) significantly decreased the tolerance of yeast to inhibitors, which further suggested that yeast responded to the inhibitors mainly by inducing unfolded protein response. This study reveals that increasing the detoxification and tolerating oxidative stress, and/or decreasing the nitrogen metabolism would be promising strategies in developing more tolerant strains to the multiple inhibitors in lignocellulose hydrolysates. PMID:22952687

Ding, Ming-Zhu; Wang, Xin; Liu, Wei; Cheng, Jing-Sheng; Yang, Yang; Yuan, Ying-Jin

2012-01-01

177

Production of the Angiotensin-I-Converting Enzyme (ACE)Inhibitory Peptide from Hydrolysates of Jellyfish ( Rhopilema esculentum ) Collagen  

Microsoft Academic Search

Collagen extracted from jellyfish (Rhopilema esculentum) was hydrolyzed with alcalase to prepare the ACE-inhibitory peptide. The optimal hydrolyzing conditions were determined using\\u000a response surface methodology. The results showed that the optimal conditions were temperature of 52.7 °C, pH of 8.63 and enzyme-to-substrate\\u000a ratio (E\\/S) of 3.46%, and the ACE-inhibitory activity of the obtained hydrolysates could reach 81.7%. Jellyfish collagen peptide, UF3-B2,

Yongliang Zhuang; Liping Sun; Bafang Li

178

Simple and sensitive method for quantification of fluorescent enzymatic mature and senescent crosslinks of collagen in bone hydrolysate using single-column high performance liquid chromatography  

Microsoft Academic Search

A rapid high performance liquid chromatographic method was developed including an internal standard for the measurement of mature and senescent crosslinks concentration in non-demineralized bone hydrolysates. To avoid the demineralization which is a tedious step, we developed a method based on the use of a solid-phase extraction procedure to clean-up the samples. It resulted in sensitive and accurate measurements: the

S. Viguet-Carrin; E. Gineyts; C. Bertholon; P. D. Delmas

2009-01-01

179

Selection of Yarrowia lipolytica strains with high protein content from yeasts isolated from different marine environments  

NASA Astrophysics Data System (ADS)

A total of 78 Yarrowia lipolytica yeast strains from seawater, sediments, mud of salterns, the guts of marine fish, and marine algae were obtained. After the crude protein of the yeasts was estimated by the method of Kjehldahl, we found that seven strains of the marine yeasts grown in soy bean cake hydrolysate with 20 g L-1 of glucose for 48 h at 28°C contained more than 41.0 g protein per 100 g of cell dry weight and the cell dry weight was more than 4.4 g per L of the culture. Among them, strain SWJ-1b contained the highest crude protein. The results of Biolog identification and molecular methods further confirmed that they indeed belonged to Y. lipolytica.

Chi, Zhenming; Wang, Fang; Wang, Lin; Li, Jing; Wang, Xianghong

2007-10-01

180

Industrial robust yeast isolates with great potential for fermentation of lignocellulosic biomass.  

PubMed

The search of robust microorganisms is essential to design sustainable processes of second generation bioethanol. Yeast strains isolated from industrial environments are generally recognised to present an increased stress tolerance but no specific information is available on their tolerance towards inhibitors that come from the pretreatment of lignocellulosic materials. In this work, a strategy for the selection of different yeasts using hydrothermal hydrolysate from Eucalyptus globulus wood, containing different concentrations of inhibitors, was developed. Ten Saccharomyces cerevisiae and four Kluyveromyces marxianus strains isolated from industrial environments and four laboratory background strains were evaluated. Interestingly, a correlation between final ethanol titer and percentage of furfural detoxification was observed. The results presented here highlight industrial distillery environments as a remarkable source of efficient yeast strains for lignocellulosic fermentation processes. Selected strains were able to resourcefully degrade furfural and HMF inhibitors, producing 0.8g ethanol/Lh corresponding to 94% of the theoretical yield. PMID:24704884

Pereira, Francisco B; Romaní, Aloia; Ruiz, Héctor A; Teixeira, José A; Domingues, Lucília

2014-06-01

181

Biodegradable packing materials from hydrolysates of collagen waste proteins.  

PubMed

Enzymatic hydrolysates of waste collagen proteins (H), from current industrial manufacture (leather, edible meat product casings, etc.) of mean molecular mass 20-30 kDa by a reaction with dialdehyde starch (DAS), produces hydrogels applicable as biodegradable (or even edible) packaging materials for food, cosmetic and pharmaceutical products. Thermo-reversibility of prepared hydrogels is given by concentrations of H and DAS in a reaction mixture. At concentrations of H 25-30% (w/w) and that of DAS 15-20% (related to weight of hydrolysate), thermo-reversible hydrogels arise, which can be processed into packaging materials by a technique similar to that of soft gelatin capsules (SGC). Exceeding the limit of 20% DAS leads to hydrogels that are thermo-reversible only in part, a further increase in DAS concentration then leads to thermo-irreversible gels whose processing into biodegradable packaging materials necessitates employment of other procedures. PMID:17376664

Langmaier, F; Mokrejs, P; Kolomaznik, K; Mladek, M

2008-01-01

182

Kinetic studies of cellodextrins hydrolyses by exocellulase from trichoderma reesei  

SciTech Connect

The kinetics of the hydrolyses of cellotriose and of cellotetraose by cellobiohydrolase were studied using a convenient integral technique. Reaction mechanisms and mathematical models were postulated to describe the reactions. The end-products of the reaction were found to be inhibitory toward hydrolysis in a competitive mode. Hydrolysis of cellotraose produces cellobiose and hydrolysis of cellotriose produces cellobiose and glucose. Both sugars inhibit the enzyme with cellobiose being a stronger inhibitor.

Teh-An Hsu, Cheng-Shung Gong; Tsao, G.T.

1980-11-01

183

Biodegradable packing materials from hydrolysates of collagen waste proteins  

Microsoft Academic Search

Enzymatic hydrolysates of waste collagen proteins (H), from current industrial manufacture (leather, edible meat product casings, etc.) of mean molecular mass 20–30kDa by a reaction with dialdehyde starch (DAS), produces hydrogels applicable as biodegradable (or even edible) packaging materials for food, cosmetic and pharmaceutical products. Thermo-reversibility of prepared hydrogels is given by concentrations of H and DAS in a reaction

F. Langmaier; P. Mokrejs; K. Kolomaznik; M. Mladek

2008-01-01

184

Enzymatic hydrolysis of corncob and ethanol production from cellulosic hydrolysate  

Microsoft Academic Search

Enzymatic hydrolysis of corncob and ethanol fermentation from cellulosic hydrolysate were investigated. After corncob was pretreated by 1% H2SO4 at 108°C for 3h, the cellulosic residue was hydrolyzed by cellulase from Trichoderma reesei ZU-02 and the hydrolysis yield was 67.5%. Poor cellobiase activity in T. reesei cellulase restricted the conversion of cellobiose to glucose, and the accumulation of cellobiose caused

Ming Chen; Liming Xia; Peijian Xue

2007-01-01

185

Hydrogels of collagen hydrolysate cross-linked with dialdehyde starch  

Microsoft Academic Search

Processing hydrogels of collagen hydrolysate (H) cross-linked with dialdehyde starch (DAS) by dipping or casting into biodegradable\\u000a materials for various applications, is complicated by their marked tendency to aging. One-hour action by temperatures at 60–90 °C\\u000a reduces sorbed water content in hydrogels by approx. 12%; dependence of the extent of this reduction on temperature (within\\u000a the mentioned range) was not detected.

F. Langmaier; M. Mládek; P. Mokrejš

2009-01-01

186

Short peptide fragments with antiulcer activity from a collagen hydrolysate  

Microsoft Academic Search

A peptide acidic hydrolysate of collagen (PHC) was obtained under conditions (4 N HCl) ensuring the predominant formation\\u000a of short peptides, glyprolines. They were separated and their antiulcer activity was studied. Thirty individual peptides with\\u000a molecular masses of 174–420 amu were isolated from the PHC by HPLC. The PHC was shown to predominantly contain 2-to 4-aa peptides,\\u000a including PG, GP,

Yu. A. Zolotarev; K. E. Badmaeva; Z. V. Bakaeva; G. E. Samonina; G. N. Kopylova; A. K. Dadayan; Yu. B. Zverkov; S. K. Garanin; B. V. Vaskovsky; I. P. Ashmarin; N. F. Myasoedov

2006-01-01

187

Decomposition of hydrolysates of chemical warfare agents using photoactivated periodate  

Microsoft Academic Search

The kinetics and mechanism of periodate and photoactivated periodate oxidation of the hydrolysates of chemical warfare agents (HCWAs), thiodiglycol (TDG), 3,3-dithiopropanol (TDP), and 1,4-thioxane (TX), were investigated at pH 3, pH 7, and pH 10 under dark (in the absence of light) and monochromatic UV light irradiation. Dark reactions occurred by oxygen addition to sulfur atoms in HCWAs at pH

Xueming Tang; Linda K. Weavers

2007-01-01

188

Mitochondrial assembly in yeast  

Microsoft Academic Search

The yeast Saccharomyces cerevisiae is likely to be the first organism for which a complete inventory of mitochondrial proteins and their functions can be drawn up. A survey of the 340 or so proteins currently known to be localised in yeast mitochondria reveals the considerable investment required to maintain the organelle’s own genetic system, which itself contributes seven key components

Les A Grivell; Marta Artal-Sanz; Gertjan Hakkaart; Liesbeth de Jong; Leo G. J Nijtmans; Katinka van Oosterum; Michel Siep; Hans van der Spek

1999-01-01

189

Yeasts: Neglected Pathogens  

Microsoft Academic Search

Background: Current research on Crohn’s disease (CD) concerns molecular events related to loss of tolerance to microbes that could trigger or maintain inflammation in genetically susceptible individuals. CD is also associated with antimicrobial antibodies, including the antibodies we described against yeast oligomannosides (ASCA). This prompted us to investigate a role for another yeast, Candida albicans, a very common commensal of

Daniel Poulain; Boualem Sendid; Annie Standaert-Vitse; Chantal Fradin; Thierry Jouault; Samir Jawhara; Jean-Frederic Colombel

2009-01-01

190

Antioxidant properties of Australian canola meal protein hydrolysates.  

PubMed

Antioxidant activities of canola protein hydrolysates (CPHs) and peptide fractions prepared using five proteases and ultrafiltration membranes (1, 3, 5, and 10kDa) were investigated. CPHs had similar and adequate quantities of essential amino acids. The effective concentration that scavenged 50% (EC50) of the ABTS(+) was greatest for the <1kDa pancreatin fraction at 10.1?g/ml. CPHs and peptide fractions scavenged DPPH(+) with most of the EC50 values being <1.0mg/ml. Scavenging of superoxide radical was generally weak, except for the <1kDa pepsin peptide fraction that had a value of 51%. All CPHs inhibited linoleic acid oxidation with greater efficiency observed for pepsin hydrolysates. The oxygen radical absorbance capacity of Alcalase, chymotrypsin and pepsin hydrolysates was found to be better than that of glutathione (GSH) (p<0.05). These results show that CPHs have the potential to be used as bioactive ingredients in the formulation of functional foods against oxidative stress. PMID:24176374

Alashi, Adeola M; Blanchard, Christopher L; Mailer, Rodney J; Agboola, Samson O; Mawson, A John; He, Rong; Girgih, Abraham; Aluko, Rotimi E

2014-03-01

191

The Use of Protein Hydrolysates for Weed Control  

NASA Astrophysics Data System (ADS)

Corn gluten meal, the protein fraction of corn (Zea mays L.) grain, is commercially used as a natural weed control agent and nitrogen source in horticultural crops and in the turf and ornamental markets. Corn gluten hydrolysate, a water soluble form of gluten meal, has also been proposed for the same purpose, although it could be sprayed on the soil rather than applied in the granular form. Five depeptides, glutaminyl-glutamine (Gln-Gln), glycinyl-alanine (Gly-Ala), alanyl-­glutamine (Ala-Glu), alanyl-asparagine (Ala-Asp), and alaninyl-alanine (Ala-Ala) and a pentapeptide leucine-serine-proline-alanine-glutamine (Leu-Ser-Pro-Ala-Gln) were identified as the active components of the hydrolysate. Microscopic analysis revealed that Ala-Ala acted on some metabolic process rather than directly on the mitotic apparatus. Similar to the chloracetamides and sulfonyl-urea hebicides, Ala-Ala inhibits cell division rather than disrupting of cell division processes. Cellular ultrastructure changes caused by exposure to Ala-Ala implicate Ala-Ala as having membrane-disrupting characteristics similar to several synthetic herbicides. The potential use of the hydrolysate and the peptides as weed controls is discussed.

Christians, Nick; Liu, Dianna; Unruh, Jay Bryan

192

Extensively and partially hydrolysed infant formulas for allergy prophylaxis  

PubMed Central

Accepted 17 March 1997? The allergy preventive effect of extensively (N) and partially (PH) hydrolysed cows' milk formulas compared with a regular formula (RM) was assessed in 155 infants with a family history of allergy. No cows' milk was given during the first nine months of life and no egg and fish up to 12 months of age. Breast feeding mothers avoided the same foods. At weaning the infants were randomised to one of the formula groups. The cumulative incidence of atopic symptoms at 18 months was 51, 64, and 84% in the N, PH, and RM groups, respectively. From 6 to 18 months there were significantly less cumulative atopic symptoms in the N group compared with the RM group, and significantly less than the PH group up to 6 (N= 25%; PH = 46%) and 9 months (N = 34%, PH = 58%). At 9 months significantly fewer infants in the N group (10%) than in the PH group (33%) had a positive skin prick test to eggs. The findings support an allergy preventive effect of an extensively hydrolysed formula, but not of a partially hydrolysed formula, during the first 18 months of life of high risk infants.?? PMID:9279143

Oldaeus, G; Anjou, K; Bjorksten, B; Moran, J; Kjellman, N

1997-01-01

193

The effects of inulin supplementation of diets with or without hydrolysed protein sources on digestibility, faecal characteristics, haematology and immunoglobulins in dogs.  

PubMed

Dogs with food allergy are often treated by giving a diet with hydrolysed protein sources. Prebiotics might also be successful in prevention and treatment of allergic disease through their effect on the colonic microflora, analogous to studies on probiotics in allergic children. The present study was set up to investigate the effect of supplementing inulin (IN) to commercial hypoallergenic dog diets on apparent nutrient digestibility, faecal characteristics, haematology and Ig in dogs. Supplementation of 3 % IN did not affect faecal pH, food and water intake and urine production. Compared with the intact protein diet with a limited number of ingredients (L), the diet with a hydrolysed protein source (H) resulted in an increased water intake (P<0.001), which could be due to the osmotic effect of free amino acids. Faeces production was increased by IN due to increased faecal moisture content. Increased faeces production on the H diet was mainly due to a higher DM excretion. Subsequently, the apparent digestibility coefficient (ADC) of DM was lower in the H diet group. A similar result was noted for ADC of diethyl ether extract and crude ash. The ADC of crude protein was higher in the H diet group, whereas IN decreased the ADC of crude protein. Differences in the ADC of crude protein among the different diets disappeared after correction for a higher faecal biomass, except for the dogs fed the L+IN diet. Total faecal IgA concentrations were lower in the H group (P<0.05) because of lower antigenic stimulation of hydrolysed protein, which implies that hydrolysed protein is really hypoallergenic. The present study indicates that the use of hydrolysed protein diets for canine food allergy treatment can affect digestibility and that combination with IN affected apparent protein digestibility but not IgA response. PMID:17092385

Verlinden, A; Hesta, M; Hermans, J M; Janssens, G P J

2006-11-01

194

Prions in Yeast  

PubMed Central

The concept of a prion as an infectious self-propagating protein isoform was initially proposed to explain certain mammalian diseases. It is now clear that yeast also has heritable elements transmitted via protein. Indeed, the “protein only” model of prion transmission was first proven using a yeast prion. Typically, known prions are ordered cross-? aggregates (amyloids). Recently, there has been an explosion in the number of recognized prions in yeast. Yeast continues to lead the way in understanding cellular control of prion propagation, prion structure, mechanisms of de novo prion formation, specificity of prion transmission, and the biological roles of prions. This review summarizes what has been learned from yeast prions. PMID:22879407

Liebman, Susan W.; Chernoff, Yury O.

2012-01-01

195

Purification and identification of antioxidant peptides from walnut (Juglans regia L.) protein hydrolysates.  

PubMed

Walnut proteins were hydrolyzed separately using three different proteases to obtain antioxidant peptides. The antioxidant activities of the hydrolysates were measured using 1,1-diphenyl-2-picryl hydrazyl (DPPH) assay. Among hydrolysates, pepsin hydrolysate obtained by 3h exhibited the highest antioxidant activities, which could also quench the hydroxyl radical, chelate ferrous ion, exhibit reducing power and inhibit the lipid peroxidation. Then, 3-h pepsin hydrolysates were purified sequentially by ultrafiltration, gel filtration and RP-HPLC. The sequence of the peptide with the highest antioxidative activity was identified to be Ala-Asp-Ala-Phe (423.23 Da) using RP-HPLC-ESI-MS, which was identified for the first time from walnut protein hydrolysates. Last, the inhibition of the peptide on lipid peroxidation was similar with that of reduced glutathione (GSH). These results indicate that the protein hydrolysates and/or its isolated peptides may be effectively used as food additives. PMID:23022588

Chen, Ning; Yang, Hongmei; Sun, Yi; Niu, Jun; Liu, Shuying

2012-12-01

196

Xylitol production from corn fiber and sugarcane bagasse hydrolysates by Candida tropicalis  

Microsoft Academic Search

A natural isolate, Candida tropicalis was tested for xylitol production from corn fiber and sugarcane bagasse hydrolysates. Fermentation of corn fiber and sugarcane bagasse hydrolysate showed xylose uptake and xylitol production, though these were very low, even after hydrolysate neutralization and treatments with activated charcoal and ion exchange resins. Initial xylitol production was found to be 0.43g\\/g and 0.45g\\/g of

R. Sreenivas Rao; Ch. Pavana Jyothi; R. S. Prakasham; P. N. Sarma; L. Venkateswar Rao

2006-01-01

197

Antioxidant activity and water-holding capacity of canola protein hydrolysates  

Microsoft Academic Search

Canola protein hydrolysates were prepared using commercial enzymes, namely Alcalase, an endo-peptidase and Flavourzyme with both endo- and exo-peptidase activities. The hydrolysates so prepared were effective as antioxidants in model systems, mainly by scavenging of free radicals and acting as reducing agents. This effect was concentration-dependent and also influenced by the type of enzyme employed in the process. The hydrolysate

Nichole Cumby; Ying Zhong; Marian Naczk; Fereidoon Shahidi

2008-01-01

198

Chemical and thermal cross-linking of collagen and elastin hydrolysates  

Microsoft Academic Search

Chemical and thermal cross-linking of collagen soluble in acetic acid and elastin hydrolysates soluble in water have been studied. Solutions of collagen and elastin hydrolysates were treated using variable concentrations of 1-ethyl-3(3-dimethyl aminopropyl) carbodiimide (EDC) and N-hydroxysuccinimide (NHS). Moreover, diepoxypropylether (DEPE) has been used as cross-linking agent. Films made of collagen and elastin hydrolysates were also treated with temperature at

A. Sionkowska; J. Skopinska-Wisniewska; M. Gawron; J. Kozlowska; A. Planecka

2010-01-01

199

Study on Enzymatic Hydrolysis of Gadus morrhua Skin Collagen and Molecular Weight Distribution of Hydrolysates  

Microsoft Academic Search

Process parameters on enzymatic hydrolysis and molecular weight (MW) distribution of collagen hydrolysates from Gadus morrhua skin were investigated. The optimal process parameters were obtained by the single-factor and orthogonal experiments. The molecular weight distribution of hydrolysates was determined using both Sephadex G25 partition and high speed liquid chromatography electricity spray mass spectrum (HPLC-ESI-MS). Collagen hydrolysates were first gained by

Jian-xin HUO; Zheng ZHAO

2009-01-01

200

A study of ethanol tolerance in yeast.  

PubMed

The ethanol tolerance of yeast and other microorganisms has remained a controversial area despite the many years of study. The complex inhibition mechanism of ethanol and the lack of a universally accepted definition and method to measure ethanol tolerance have been prime reasons for the controversy. A number of factors such as plasma membrane composition, media composition, mode of substrate feeding, osmotic pressure, temperature, intracellular ethanol accumulation, and byproduct formation have been shown to influence the ethanol tolerance of yeast. Media composition was found to have a profound effect upon the ability of a yeast strain to ferment concentrated substrates (high osmotic pressure) and to ferment at higher temperatures. Supplementation with peptone-yeast extract, magnesium, or potassium salts has a significant and positive effect upon overall fermentation rates. An intracellular accumulation of ethanol was observed during the early stages of fermentation. As fermentation proceeds, the intracellular and extracellular ethanol concentrations become similar. In addition, increases in osmotic pressure are associated with increased intracellular accumulation of ethanol. However, it was observed that nutrient limitation, not increased intracellular accumulation of ethanol, is responsible to some extent for the decreases in growth and fermentation activity of yeast cells at higher osmotic pressure and temperature. PMID:2178780

D'Amore, T; Panchal, C J; Russell, I; Stewart, G G

1990-01-01

201

An Ontology-Empowered Model for Annotating Protein-Protein Interaction Data: a Case Study for Budding Yeast  

E-print Network

for Budding Yeast Arash Shaban-Nejad and Volker Haarslev Dept. Computer Science and Software Eng to support and improve data mining tasks of yeast protein interactions for knowledge discovery on our experience in extracting knowledge from current data and information sources of the yeast protein

Haarslev, Volker

202

Yeast Proteome Analysis  

NASA Astrophysics Data System (ADS)

Yeast organisms, and specifically Saccharomyces cerevisiae, have become model systems for many aspects in fundamental and applied research. Consistently, many papers have been published applying proteome techniques to study these organisms. The review will give an overview on the proteome research performed on yeast systems so far; however, due to the large number of publications, only selected reports can be cited neglecting many more interesting ones in the interest of space. The review will focus on research involving mass spectrom-etry as a basic proteome technique, although many more approaches are relevant for the functional characterization of proteins in the cell, e.g. the yeast two-hybrid system. We will provide an overview on yeasts as models in the context of pro-teome analysis, and explain the basic techniques currently applied in proteome approaches. The main part of the review will deal with a survey on the current status of proteomic studies in yeasts. In a first part of this chapter, we will deal with the currently available proteome maps of yeasts, and in the following part we will discuss studies dealing with fundamental aspects, but also mention proteome studies related to applied microbiology. Finally, we will envisage future perspectives of the proteome technology for studying yeasts, and draw major conclusion on the current status reached in this field of functional genomics.

Matros, Andrea; Mock, Hans-Peter

203

Yeast transcription factors Kevin Struhl  

E-print Network

Yeast transcription factors Kevin Struhl Harvard Medical School, Boston, USA Studies of yeast Transcriptional regulatory mechanisms are fundamentally similar in eukaryotic organisms from yeasts to humans (for reviews of yeast transcription, see [1,2]). Compo- nents of the chromatin template and the basic RNA

204

Improved alcohol production employing SSF with thermotolerant yeast  

SciTech Connect

Simultaneous saccharification and fermentation (SSF) involves the enzymatic hydrolysis of cellulose and the yeast fermentation of sugars to ethanol simultaneously in the same reactor. For the effective SSF process to produce ethanol from lignocellulose, it is required to remove the physical and chemical barrier around cellulose fibers and make cellulose more accessible to cellulose. Furthermore, it is preferred to have the compatible fermentation and saccharification conditions (e.g., temperature and pH). The process for pretreatment of lignocellulosic biomass involves the steeping in ammonia solution to remove lignin followed by dilute acid (1%, w/w) hydrolysis of hemicellulose fraction. The ammonia steeping removes over 70% of lignin and consequently facilitates the removal of hemicellulose by dilute acid. Dilute acid hydrolysis of hemicellulose yielding hydrolysate with sugar concentration of up to 8%. This fraction was used as substrate for ethanol production with xylose fermenting yeast strain. After lignin and hemicellulose were removed, the cellulose fraction was used as substrate in the SSF process for ethanol production. High yield of ethanol of over 60 g/L was produced by the thermotolerant yeast within 80 hours of SSF with a low enzyme loading of 8 IFPU/g cellulose.

Tsao, G.T.; Cao, N.; Gong, C.S. [Purdue Univ., West Lafayette, IN (United States)

1996-12-31

205

Transcriptomic analysis of Clostridium thermocellum Populus hydrolysate-tolerant mutant strain shows increased cellular efficiency in response to Populus hydrolysate compared to the wild type strain  

PubMed Central

Background The thermophilic, anaerobic bacterium, Clostridium thermocellum is a model organism for consolidated processing due to its efficient fermentation of cellulose. Constituents of dilute acid pretreatment hydrolysate are known to inhibit C. thermocellum and other microorganisms. To evaluate the biological impact of this type of hydrolysate, a transcriptomic analysis of growth in hydrolysate-containing medium was conducted on 17.5% v/v Populus hydrolysate-tolerant mutant (PM) and wild type (WT) strains of C. thermocellum. Results In two levels of Populus hydrolysate medium (0% and 10% v/v), the PM showed both gene specific increases and decreases of gene expression compared to the wild-type strain. The PM had increased expression of genes in energy production and conversion, and amino acid transport and metabolism in both standard and 10% v/v Populus hydrolysate media. In particular, expression of the histidine metabolism increased up to 100 fold. In contrast, the PM decreased gene expression in cell division and sporulation (standard medium only), cell defense mechanisms, cell envelope, cell motility, and cellulosome in both media. The PM downregulated inorganic ion transport and metabolism in standard medium but upregulated it in the hydrolysate media when compared to the WT. The WT differentially expressed 1072 genes in response to the hydrolysate medium which included increased transcription of cell defense mechanisms, cell motility, and cellulosome, and decreased expression in cell envelope, amino acid transport and metabolism, inorganic ion transport and metabolism, and lipid metabolism, while the PM only differentially expressed 92 genes. The PM tolerates up to 17.5% v/v Populus hydrolysate and growth in it elicited 489 genes with differential expression, which included increased expression in energy production and conversion, cellulosome production, and inorganic ion transport and metabolism and decreased expression in transcription and cell defense mechanisms. Conclusion These results suggest the mechanisms of tolerance for the Populus hydrolysate-tolerant mutant strain of C. thermocellum are based on increased cellular efficiency caused apparently by downregulation of non-critical genes and increasing the expression of genes in energy production and conversion rather than tolerance to specific hydrolysate components. The wild type, conversely, responds to hydrolysate media by down-regulating growth genes and up-regulating stress response genes. PMID:25128475

2014-01-01

206

RNAi in Budding Yeast  

E-print Network

RNA interference (RNAi), a gene-silencing pathway triggered by double-stranded RNA, is conserved in diverse eukaryotic species but has been lost in the model budding yeast Saccharomyces cerevisiae. Here, we show that RNAi ...

Drinnenberg, Ines A.

207

RNAi in budding yeast.  

PubMed

RNA interference (RNAi), a gene-silencing pathway triggered by double-stranded RNA, is conserved in diverse eukaryotic species but has been lost in the model budding yeast Saccharomyces cerevisiae. Here, we show that RNAi is present in other budding yeast species, including Saccharomyces castellii and Candida albicans. These species use noncanonical Dicer proteins to generate small interfering RNAs, which mostly correspond to transposable elements and Y' subtelomeric repeats. In S. castellii, RNAi mutants are viable but have excess Y' messenger RNA levels. In S. cerevisiae, introducing Dicer and Argonaute of S. castellii restores RNAi, and the reconstituted pathway silences endogenous retrotransposons. These results identify a previously unknown class of Dicer proteins, bring the tool of RNAi to the study of budding yeasts, and bring the tools of budding yeast to the study of RNAi. PMID:19745116

Drinnenberg, Ines A; Weinberg, David E; Xie, Kathleen T; Mower, Jeffrey P; Wolfe, Kenneth H; Fink, Gerald R; Bartel, David P

2009-10-23

208

[Penicillium-inhibiting yeasts].  

PubMed

The objective of this work was to establish the in vitro and in vivo inhibition of post-harvest pathogenic moulds by yeasts in order to make a biocontrol product. Post-harvest pathogenic moulds Penicillium digitatum, P. italicum, P. ulaiense, Phyllosticta sp., Galactomyces geotrichum and yeasts belonging to genera Brettanomyces, Candida, Cryptococcus, Kloeckera, Pichia, Rhodotorula were isolated from citrus fruits. Some yeasts strains were also isolated from other sources. The yeasts were identified by their macro and micro-morphology and physiological tests. The in vitro and in vivo activities against P. digitatum or P. ulaiense were different. Candida cantarellii and one strain of Pichia subpelliculosa produced a significant reduction of the lesion area caused by the pathogenic moulds P. digitatum and P. ulaiense, and could be used in a biocontrol product formulation. PMID:15786872

Benítez Ahrendts, M R; Carrillo, L

2004-01-01

209

[Prevention and therapeutic effects of sika deer velvet collagen hydrolysate on osteoporosis in rats by retinoic acid].  

PubMed

The objective was to evaluate the preventive and therapeutic effects of the collagen hydrolysate extracted from Sika deer velvet (CSDV) on osteoporosis rats induced by retinoicacid. Histomorphometric indices and serum biochemical parameters were measured in osteoporosis rats treated with/without antler collagen and in sham-operated rats. Our results were as follows: compared with the osteoporosis group, significant elevation in the levels of bone mineral density (BMD), Ca, P and static histomorphometric indexes and biomechanical properties, but reduction in the level of serum alkaline phosphatase (ALP) were observed in antler collagen-treated groups. However, the above function with the collagenase solution velvet material varied with the different doses. In conclusion, the extracted collagen is found to play a role in the prevention and treatment of osteoporosis rats by retinoic acid. PMID:20545204

Li, Yinqing; Zhao, Yu; Sun, Xiaodi; Qu, Xiaobo

2010-03-01

210

Nitrile Metabolizing Yeasts  

NASA Astrophysics Data System (ADS)

Nitriles and amides are widely distributed in the biotic and abiotic components of our ecosystem. Nitrile form an important group of organic compounds which find their applications in the synthesis of a large number of compounds used as/in pharmaceutical, cosmetics, plastics, dyes, etc>. Nitriles are mainly hydro-lyzed to corresponding amide/acid in organic chemistry. Industrial and agricultural activities have also lead to release of nitriles and amides into the environment and some of them pose threat to human health. Biocatalysis and biotransformations are increasingly replacing chemical routes of synthesis in organic chemistry as a part of ‘green chemistry’. Nitrile metabolizing organisms or enzymes thus has assumed greater significance in all these years to convert nitriles to amides/ acids. The nitrile metabolizing enzymes are widely present in bacteria, fungi and yeasts. Yeasts metabolize nitriles through nitrilase and/or nitrile hydratase and amidase enzymes. Only few yeasts have been reported to possess aldoxime dehydratase. More than sixty nitrile metabolizing yeast strains have been hither to isolated from cyanide treatment bioreactor, fermented foods and soil. Most of the yeasts contain nitrile hydratase-amidase system for metabolizing nitriles. Transformations of nitriles to amides/acids have been carried out with free and immobilized yeast cells. The nitrilases of Torulopsis candida>and Exophiala oligosperma>R1 are enantioselec-tive and regiospecific respectively. Geotrichum>sp. JR1 grows in the presence of 2M acetonitrile and may have potential for application in bioremediation of nitrile contaminated soil/water. The nitrilase of E. oligosperma>R1 being active at low pH (3-6) has shown promise for the hydroxy acids. Immobilized yeast cells hydrolyze some additional nitriles in comparison to free cells. It is expected that more focus in future will be on purification, characterization, cloning, expression and immobilization of nitrile metabolizing enzymes of yeasts.

Bhalla, Tek Chand; Sharma, Monica; Sharma, Nitya Nand

211

ACE inhibitory and antihypertensive properties of apricot almond meal hydrolysate  

Microsoft Academic Search

Apricot almond meal was hydrolyzed simultaneously with Neutrase and N120P proteases. The hydrolysate almond peptide (AP) was\\u000a fractionated into three ranges of molecular weight (AP-I, >5 kDa; AP-II, 1–5 kDa; AP-III, <1 kDa) using an ultrafiltration\\u000a membrane bioreactor system. The AP-III brought about a high angiotensin-I-converting enzyme (ACE) inhibitory activity with\\u000a IC50 value of 0.138 mg mL?1 and the content of hydrophobic amino acid of

Chunyan WangJinqiang; Jinqiang Tian; Qiang Wang

2011-01-01

212

Ethanol production from enzymatic hydrolysates of sugarcane bagasse using recombinant xylose-utilising Saccharomyces cerevisiae  

Microsoft Academic Search

Sugarcane bagasse was pre-treated by steam explosion at 205 and 215°C and hydrolysed with cellulolytic enzymes. The hydrolysates were subjected to enzymatic detoxification by treatment with the phenoloxidase laccase and to chemical detoxification by overliming. Approximately 80% of the phenolic compounds were specifically removed by the laccase treatment. Overliming partially removed the phenolic compounds, but also other fermentation inhibitors such

Carlos Mart??n; Mats Galbe; C. Fredrik Wahlbom; Bärbel Hahn-Hägerdal; Leif J Jönsson

2002-01-01

213

Characterization and Antioxidant Properties of Hemp Protein Hydrolysates Obtained with Neutrase  

Microsoft Academic Search

Summary Hemp protein hydrolysates with various yields of trichloroacetic acid (TCA)-soluble peptides (Ysp) and surface hydrophobicity (Ho) were obtained by Neutrase ® hydrolysis from hemp protein isolate (HPI). The peptide profiles, amino acid composition and antioxidant activities (DPPH radical scavenging ability, reducing power and Fe2+ chelating ability) of the hydrolysates, obtained at 60-240 min, were evaluated. Higher DPPH radical scaveng-

Xian-Sheng Wang; Chuan-He Tang; Ling Chen; Xiao-Quan Yang

214

Water sorption and glass transition properties of spray dried lactose hydrolysed skim milk powder  

Microsoft Academic Search

The moisture sorption behaviour and glass transition temperature of spray dried skim milk powder with hydrolysed lactose (SMPHL) were determined. Spray drying of skim milk with hydrolysed lactose resulted in very low cyclone recovery of 25% and a large amount of powder remained stuck inside the spray dryer. The equilibrium moisture content of SMPHL was lower than that of lactose

Ashok K. Shrestha; Tony Howes; Benu P. Adhikari; Bhesh R. Bhandari

2007-01-01

215

Development of a simple and sensitive fluorimetric method for isolation of coumaphos-hydrolysing bacteria  

E-print Network

-hydrolysing bacteria R.L. Harcourt*, I. Horne, T.D. Sutherland, B.D. Hammock1 , R.J. Russell and J.G. Oakeshott . Incorporation of coumaphos into agar plates allowed the rapid detection of coumaphos-hydrolysing bacteria when tool to screen for bacteria possessing phosphotriesterase activity. INTRODUCTION Organophosphorus (OP

Hammock, Bruce D.

216

Hypolipidemic Effects of Guar Gum and Its Enzyme Hydrolysate in Rats Fed Highly Saturated Fat Diets  

Microsoft Academic Search

The effects of guar gum and its enzyme hydrolysate as well as fructooligosaccharide on lipid metabolism were compared in rats fed high-fat diets employing lard or palm oil as dietary fat (25% in the diets). Guar gum and the enzyme hydrolysate greatly increased cecal volatile fatty acid contents to a similar extent. Fructooligosaccharide also increased the variable but to a

Takashi Ide; Hiroshi Moriuchi; Katsuya Nihimoto

1991-01-01

217

Improved Bioethanol Production Using Activated Carbon-treated Acid Hydrolysate from Corn Hull in Pachysolen tannophilus  

PubMed Central

To optimally convert corn hull, a byproduct from corn processing, into bioethanol using Pachysolen tannophlius, we investigated the optimal conditions for hydrolysis and removal of toxic substances in the hydrolysate via activated carbon treatment as well as the effects of this detoxification process on the kinetic parameters of bioethanol production. Maximum monosaccharide concentrations were obtained in hydrolysates in which 20 g of corn hull was hydrolyzed in 4% (v/v) H2SO4. Activated carbon treatment removed 92.3% of phenolic compounds from the hydrolysate. When untreated hydrolysate was used, the monosaccharides were not completely consumed, even at 480 h of culture. When activated carbon-treated hydrolysate was used, the monosaccharides were mostly consumed at 192 h of culture. In particular, when activated carbon-treated hydrolysate was used, bioethanol productivity (P) and specific bioethanol production rate (Qp) were 2.4 times and 3.4 times greater, respectively, compared to untreated hydrolysate. This was due to sustained bioethanol production during the period of xylose/arabinose utilization, which occurred only when activated carbon-treated hydrolysate was used. PMID:23983522

Seo, Hyeon-Beom; Kim, Seungseop; Lee, Hyeon-Yong

2009-01-01

218

Anti-oxidative and anti-aging activities of collagen hydrolysate  

Microsoft Academic Search

Collagen is a family of fibrous proteins present in skin, bone, tendon, teeth, cartilage of multicellular organisms. Collagen and its hydrolysate were prepared from squid skin hydrolyzed with proteases. The collagen hydrolysate obtained could remarkably extend the lifespan of fruit fly Drosophila Melanogaster. The maximum lifespan fruit flies increased from 60 days (control groups), to 80 to 84 days (treated

Chengchu Liu; Dexiang Peng; Jingya Yang; Yingsen Li; Jiale Li

2010-01-01

219

Efficient production of pullulan using rice hull hydrolysate by adaptive laboratory evolution of Aureobasidium pullulans.  

PubMed

Pullulan production by Aureobasidium pullulans CCTCC M 2012259 using rice hull hydrolysate as the carbon source was conducted. The acetic acid in the hydrolysate was demonstrated to exert a negative effect on pullulan biosynthesis. Instead of employing expensive methods to remove acetic acid from the hydrolysate, a mutant A. pullulans ARH-1 was isolated following 20 cycles of adaptive laboratory evolution of the parental strain on medium containing acetic acid. The maximum pullulan production achieved by the adapted mutant at 48 h using the hydrolysate of untreated rice hull was 22.2 g L(-1), while that obtained by the parental strain at 60 h was 15.6 g L(-1). The assay of key enzymes associated with pullulan biosynthesis revealed that acetic acid inhibited enzyme activity rather than suppressing enzyme synthesis. These results demonstrated that adaptive evolution highly improved the efficiency of pullulan production by A. pullulans using the hydrolysate of untreated rice hull. PMID:24835913

Wang, Dahui; Ju, Xiaomin; Zhou, Donghai; Wei, Gongyuan

2014-07-01

220

Temperature-dependent FTIR spectra of collagen and protective effect of partially hydrolysed fucoidan  

NASA Astrophysics Data System (ADS)

FTIR spectra of collagen (PC) and partially hydrolysed fucoidan (PHF) incorporated into collagen films were investigated at different temperatures between 20 °C and 100 °C. Changes within the bands of amide I, amide II and amide III may indicate stabilization of collagen by hydrogen bonds during its interaction with partially hydrolysed fucoidan. Spectroscopic studies revealed that partially hydrolysed fucoidan was bound to the collagen without affecting its triple helicity. Interactions of fucoidan with H2SO4 (mild acid hydrolysis), leading to changes of the sulphated band positions in the 800-590 cm-1 region of IR spectra were observed. The effect of partially hydrolysed fucoidan on glucose-mediated collagen glycation and cross-linking of proteins in vitro was evaluated. It was observed that partially hydrolysed fucoidan incorporated into collagen films can be used as therapeutically active biomaterials that speed up the process of wound healing and may increase the anticancer activity of fucoidan.

Pielesz, Anna

2014-01-01

221

Temperature-dependent FTIR spectra of collagen and protective effect of partially hydrolysed fucoidan.  

PubMed

FTIR spectra of collagen (PC) and partially hydrolysed fucoidan (PHF) incorporated into collagen films were investigated at different temperatures between 20°C and 100°C. Changes within the bands of amide I, amide II and amide III may indicate stabilization of collagen by hydrogen bonds during its interaction with partially hydrolysed fucoidan. Spectroscopic studies revealed that partially hydrolysed fucoidan was bound to the collagen without affecting its triple helicity. Interactions of fucoidan with H2SO4 (mild acid hydrolysis), leading to changes of the sulphated band positions in the 800-590 cm(-1) region of IR spectra were observed. The effect of partially hydrolysed fucoidan on glucose-mediated collagen glycation and cross-linking of proteins in vitro was evaluated. It was observed that partially hydrolysed fucoidan incorporated into collagen films can be used as therapeutically active biomaterials that speed up the process of wound healing and may increase the anticancer activity of fucoidan. PMID:24055677

Pielesz, Anna

2014-01-24

222

In vitro antioxidant and antibacterial properties of hydrolysed proteins of delimed tannery fleshings: comparison of acid hydrolysis and fermentation methods.  

PubMed

Proteins in delimed tannery fleshings were fermentatively hydrolysed using Enterococcus faecium NCIM5335 and also hydrolysed using mild organic acids (formic acid and propionic acid). The liquor portion containing hydrolysed proteins was spray dried, in both the cases, to obtain a powder. The spray dried powder was evaluated for in vitro antioxidant activities with respect to scavenging different free radicals and antibacterial properties against nine different pathogens. Fermentation and acid hydrolysates scavenged 83 and 75.3% of 2,2-azino-bis-3-ethyl-benzthiazoline-6-sulphonic acid (ABTS) radicals, respectively, at a protein concentration of 0.25 mg. Further, fermentation hydrolysate showed higher 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity of 59% as compared to 56% scavenging by acid hydrolysate at a protein concentration of 5 mg. Acid hydrolysate exhibited lesser (82.3%) peroxy radical scavenging compared to hydrolysate from fermentation (88.2%) at a protein concentration of 10 mg. However, acid hydrolysate exhibited higher (89.2%) superoxide anion scavenging while its fermentation counterpart showed lower activity (85.4%) at 2.5 mg hydrolysate protein. Well as superoxide anion scavenging properties. All the in vitro antioxidant properties exhibited dose dependency. Fermentation hydrolysate exhibited maximum antagonistic activity against Salmonella typhi FB231, from among host of pathogens evaluated. Both the hydrolysates have potential to be ingredients in animal feeds and can help reduce oxidative stress in the animals. PMID:20680665

Balakrishnan, Bijinu; Prasad, Binod; Rai, Amit Kumar; Velappan, Suresh Puthanveetil; Subbanna, Mahendrakar Namadev; Narayan, Bhaskar

2011-04-01

223

Microbial oil production from rice straw hydrolysate by Trichosporon fermentans.  

PubMed

Microbial oil production from sulphuric acid treated rice straw hydrolysate (SARSH) by Trichosporon fermentans was performed for the first time. Fermentation of SARSH without detoxification gave a poor lipid yield of 1.7 g/l, which was much lower than the result with glucose or xylose as the single carbon source (13.6 g/l or 9.9 g/l). The detoxification pretreatment, including overliming, concentration, and adsorption by Amberlite XAD-4 improved the fermentability of SARSH significantly by removing the inhibitors in SARSH. A total biomass of 28.6 g/l with a lipid content of 40.1% (corresponding to a lipid yield of 11.5 g/l) could be achieved after cultivation of T. fermentans on the detoxified SARSH for 8 days. Moreover, besides SARSH, T. fermentans could also utilize mannose, galactose, or cellobiose, in hydrolysates of other natural lignocellulosic materials as the single carbon source to grow and accumulate lipid with a high yield (at least 10.4 g/l). Hence, it is a promising strain for microbial oil production and thus biodiesel preparation from agro-industrial residues, especially lignocellulosic materials. PMID:19433350

Huang, Chao; Zong, Min-hua; Wu, Hong; Liu, Qiu-ping

2009-10-01

224

Development and validation of an in-house database for matrix-assisted laser desorption ionization-time of flight mass spectrometry-based yeast identification using a fast protein extraction procedure.  

PubMed

In recent studies evaluating the usefulness of the matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS)-based identification of yeasts for the routine diagnosis of fungal infections, preanalytical sample processing has emerged as a critical step for reliable MALDI-TOF MS outcomes, especially when the Bruker Daltonics Biotyper software was used. In addition, inadequate results often occurred due to discrepancies between the methods used for clinical testing and database construction. Therefore, we created an in-house MALDI-TOF MS library using the spectra from 156 reference and clinical yeast isolates (48 species in 11 genera), which were generated with a fast sample preparation procedure. After a retrospective validation study, our database was evaluated on 4,232 yeasts routinely isolated during a 6-month period and fast prepared for MALDI-TOF MS analysis. Thus, 4,209 (99.5%) of the isolates were successfully identified to the species level (with scores of ?2.0), with 1,676 (39.6%) having scores of >2.3. For the remaining 23 (0.5%) isolates, no reliable identification (with scores of <1.7) was obtained. Interestingly, these isolates were almost always from species uniquely represented or not included in the database. As the MALDI-TOF MS results were, except for 23 isolates, validated without additional phenotypic or molecular tests, our proposed strategy can enhance the rapidity and accuracy of MALDI-TOF MS in identifying medically important yeast species. However, while continuous updating of our database will be necessary to enrich it with more strains/species of new and emerging yeasts, the present in-house MALDI-TOF MS library can be made publicly available for future multicenter studies. PMID:24554755

De Carolis, Elena; Vella, Antonietta; Vaccaro, Luisa; Torelli, Riccardo; Posteraro, Patrizia; Ricciardi, Walter; Sanguinetti, Maurizio; Posteraro, Brunella

2014-05-01

225

Development and Validation of an In-House Database for Matrix-Assisted Laser Desorption Ionization-Time of Flight Mass Spectrometry-Based Yeast Identification Using a Fast Protein Extraction Procedure  

PubMed Central

In recent studies evaluating the usefulness of the matrix-assisted laser desorption ionization–time of flight mass spectrometry (MALDI-TOF MS)-based identification of yeasts for the routine diagnosis of fungal infections, preanalytical sample processing has emerged as a critical step for reliable MALDI-TOF MS outcomes, especially when the Bruker Daltonics Biotyper software was used. In addition, inadequate results often occurred due to discrepancies between the methods used for clinical testing and database construction. Therefore, we created an in-house MALDI-TOF MS library using the spectra from 156 reference and clinical yeast isolates (48 species in 11 genera), which were generated with a fast sample preparation procedure. After a retrospective validation study, our database was evaluated on 4,232 yeasts routinely isolated during a 6-month period and fast prepared for MALDI-TOF MS analysis. Thus, 4,209 (99.5%) of the isolates were successfully identified to the species level (with scores of ?2.0), with 1,676 (39.6%) having scores of >2.3. For the remaining 23 (0.5%) isolates, no reliable identification (with scores of <1.7) was obtained. Interestingly, these isolates were almost always from species uniquely represented or not included in the database. As the MALDI-TOF MS results were, except for 23 isolates, validated without additional phenotypic or molecular tests, our proposed strategy can enhance the rapidity and accuracy of MALDI-TOF MS in identifying medically important yeast species. However, while continuous updating of our database will be necessary to enrich it with more strains/species of new and emerging yeasts, the present in-house MALDI-TOF MS library can be made publicly available for future multicenter studies. PMID:24554755

De Carolis, Elena; Vella, Antonietta; Vaccaro, Luisa; Torelli, Riccardo; Posteraro, Patrizia; Ricciardi, Walter; Posteraro, Brunella

2014-01-01

226

Medium optimization for glucoamylase production by a yeast, Pichia subpelliculosa ABWF-64, in submerged cultivation  

Microsoft Academic Search

An amylolytic yeast strain Pichia subpelliculosawas shown to produce glucoamylase in submerged cultivation. The yeast strain produced the enzyme optimally at 30 °C and pH 5.6 in shake flasks agitated at 200 rev min-1 in the optimized glucoamylase production medium containing 1% starch, 0.2% yeast extract, 0.4% K2HPO4, 0.035% NaCl and 0.1% MgCl2. Maximum enzyme production was attained during early

Sanjeev Kumar; T. Satyanarayana

2001-01-01

227

Mapping Yeast Transcriptional Networks  

PubMed Central

The term “transcriptional network” refers to the mechanism(s) that underlies coordinated expression of genes, typically involving transcription factors (TFs) binding to the promoters of multiple genes, and individual genes controlled by multiple TFs. A multitude of studies in the last two decades have aimed to map and characterize transcriptional networks in the yeast Saccharomyces cerevisiae. We review the methodologies and accomplishments of these studies, as well as challenges we now face. For most yeast TFs, data have been collected on their sequence preferences, in vivo promoter occupancy, and gene expression profiles in deletion mutants. These systematic studies have led to the identification of new regulators of numerous cellular functions and shed light on the overall organization of yeast gene regulation. However, many yeast TFs appear to be inactive under standard laboratory growth conditions, and many of the available data were collected using techniques that have since been improved. Perhaps as a consequence, comprehensive and accurate mapping among TF sequence preferences, promoter binding, and gene expression remains an open challenge. We propose that the time is ripe for renewed systematic efforts toward a complete mapping of yeast transcriptional regulatory mechanisms. PMID:24018767

Hughes, Timothy R.; de Boer, Carl G.

2013-01-01

228

Oxygen requirements of yeasts.  

PubMed Central

Type species of 75 yeast genera were examined for their ability to grow anaerobically in complex and mineral media. To define anaerobic conditions, we added a redox indicator, resazurin, to the media to determine low redox potentials. All strains tested were capable of fermenting glucose to ethanol in oxygen-limited shake-flask cultures, even those of species generally regarded as nonfermentative. However, only 23% of the yeast species tested grew under anaerobic conditions. A comparative study with a number of selected strains revealed that Saccharomyces cerevisiae stands out as a yeast capable of rapid growth at low redox potentials. Other yeasts, such as Torulaspora delbrueckii and Candida tropicalis, grew poorly mu max, 0.03 and 0.05 h-1, respectively) under anaerobic conditions in mineral medium supplemented with Tween 80 and ergosterol. The latter organisms grew rapidly under oxygen limitation and then displayed a high rate of alcoholic fermentation. It can be concluded that these yeasts have hitherto-unidentified oxygen requirements for growth. Images PMID:2082825

Visser, W; Scheffers, W A; Batenburg-van der Vegte, W H; van Dijken, J P

1990-01-01

229

Yeast killer systems.  

PubMed Central

The killer phenomenon in yeasts has been revealed to be a multicentric model for molecular biologists, virologists, phytopathologists, epidemiologists, industrial and medical microbiologists, mycologists, and pharmacologists. The surprisingly widespread occurrence of the killer phenomenon among taxonomically unrelated microorganisms, including prokaryotic and eukaryotic pathogens, has engendered a new interest in its biological significance as well as its theoretical and practical applications. The search for therapeutic opportunities by using yeast killer systems has conceptually opened new avenues for the prevention and control of life-threatening fungal diseases through the idiotypic network that is apparently exploited by the immune system in the course of natural infections. In this review, the biology, ecology, epidemiology, therapeutics, serology, and idiotypy of yeast killer systems are discussed. PMID:9227858

Magliani, W; Conti, S; Gerloni, M; Bertolotti, D; Polonelli, L

1997-01-01

230

L-arabinose fermenting yeast  

DOEpatents

An L-arabinose utilizing yeast strain is provided for the production of ethanol by introducing and expressing bacterial araA, araB and araD genes. L-arabinose transporters are also introduced into the yeast to enhance the uptake of arabinose. The yeast carries additional genomic mutations enabling it to consume L-arabinose, even as the only carbon source, and to produce ethanol. Methods of producing ethanol include utilizing these modified yeast strains. ##STR00001##

Zhang, Min (Lakewood, CO); Singh, Arjun (Lakewood, CO); Knoshaug, Eric (Golden, CO); Franden, Mary Ann (Centennial, CO); Jarvis, Eric (Boulder, CO); Suominen, Pirkko (Maple Grove, MN)

2010-12-07

231

Mitochondrial assembly in yeast.  

PubMed

The yeast Saccharomyces cerevisiae is likely to be the first organism for which a complete inventory of mitochondrial proteins and their functions can be drawn up. A survey of the 340 or so proteins currently known to be localised in yeast mitochondria reveals the considerable investment required to maintain the organelle's own genetic system, which itself contributes seven key components of the electron transport chain. Translation and respiratory complex assembly are particularly expensive processes, together requiring around 150 of the proteins so far known. Recent developments in both areas are reviewed and approaches to the identification of novel mitochondrial proteins are discussed. PMID:10376678

Grivell, L A; Artal-Sanz, M; Hakkaart, G; de Jong, L; Nijtmans, L G; van Oosterum, K; Siep, M; van der Spek, H

1999-06-01

232

Ultrasonic-Assisted Enzymolysis to Improve the Antioxidant Activities of Peanut (Arachin conarachin L.) Antioxidant Hydrolysate  

PubMed Central

The objective of this work is to provide a theoretical basis for preparing peanut antioxidant hydrolysate in order to improve its antioxidant activities. Therefore, response surface methodology (RSM) based on the Box-Behnken design was used to optimize ultrasonic-assisted enzymolysis for the purpose of preparing peanut antioxidant hydrolysate. Results indicated that the DPPH free radical scavenging activity of peanut hydrolysate could reach 90.06% under the following optimum conditions: ultrasonic power of 150.0 w, reaction temperature of 62.0 °C, incubation time of 25.0 min, and initial pH value of 8.5. The DPPH free radical scavenging rate of peanut hydrolysate from ultrasonic-assisted enzymolysis improved comparing with that of peanut hydrolysate from protease hydrolysis alone. The peanut antioxidant hydrolysate was found to display eight improved kinds of antioxidant activities. In conclusion, the optimal ultrasonic-assisted enzymolysis technology conditions described in this paper, appear to be beneficial for preparing peanut antioxidant hydrolysate. PMID:22942751

Yu, Lina; Sun, Jie; Liu, Shaofang; Bi, Jie; Zhang, Chushu; Yang, Qingli

2012-01-01

233

Particle properties of sugar maple hemicellulose hydrolysate and its influence on growth and metabolic behavior of Pichia stipitis.  

PubMed

In this study the influence of the insoluble solids in nano-filtrated sugar maple hemicellulosic hydrolysate on the metabolic behavior of Pichia stiptis was investigated. The particle properties of hemicellulosic hydrolysate were analyzed. Phosphoric acid and ammonium (PA) were applied to remove the particles. The metabolic behavior and growth property of P. stipitis in particle--removed hydrolysate was measured. Results demonstrated that the average particle size and zeta potential of the untreated hydrolysate were 2266.9±78.2 nm and -6.09±0.49 mV. Xylose consumption and ethanol production rate were significantly decreased when particle content is greater than 1.63 g/L. Because the majority of particles (34 g/L) were removed from hydrolysates by phosphoric acid and ammonium treatment, the fermentability of the hydrolysate was significantly improved. These results indicated particles play an important role in hydrolysate inhibition effect. PMID:20855196

Sun, Zhijie; Shupe, Alan; Liu, Tingjun; Hu, Ruofei; Amidon, Thomas E; Liu, Shijie

2011-01-01

234

Collagen metabolism of human osteoarthritic articular cartilage as modulated by bovine collagen hydrolysates.  

PubMed

Destruction of articular cartilage is a characteristic feature of osteoarthritis (OA). Collagen hydrolysates are mixtures of collagen peptides and have gained huge public attention as nutriceuticals used for prophylaxis of OA. Here, we evaluated for the first time whether different bovine collagen hydrolysate preparations indeed modulate the metabolism of collagen and proteoglycans from human OA cartilage explants and determined the chemical composition of oligopeptides representing collagen fragments. Using biophysical techniques, like MALDI-TOF-MS, AFM, and NMR, the molecular weight distribution and aggregation behavior of collagen hydrolysates from bovine origin (CH-Alpha®, Peptan™ B 5000, Peptan™ B 2000) were determined. To investigate the metabolism of human femoral OA cartilage, explants were obtained during knee replacement surgery. Collagen synthesis of explants as modulated by 0-10 mg/ml collagen hydrolysates was determined using a novel dual radiolabeling procedure. Proteoglycans, NO, PGE(2), MMP-1, -3, -13, TIMP-1, collagen type II, and cell viability were determined in explant cultures. Groups of data were analyzed using ANOVA and the Friedman test (n?=?5-12). The significance was set to p?0.05. We found that collagen hydrolysates obtained from different sources varied with respect to the width of molecular weight distribution, average molecular weight, and aggregation behavior. None of the collagen hydrolysates tested stimulated the biosynthesis of collagen. Peptan™ B 5000 elevated NO and PGE(2) levels significantly but had no effect on collagen or proteoglycan loss. All collagen hydrolysates tested proved not to be cytotoxic. Together, our data demonstrate for the first time that various collagen hydrolysates differ with respect to their chemical composition of collagen fragments as well as by their pharmacological efficacy on human chondrocytes. Our study underscores the importance that each collagen hydrolysate preparation should first demonstrate its pharmacological potential both in vitro and in vivo before being used for both regenerative medicine and prophylaxis of OA. PMID:23342047

Schadow, Saskia; Siebert, Hans-Christian; Lochnit, Günter; Kordelle, Jens; Rickert, Markus; Steinmeyer, Jürgen

2013-01-01

235

Effect of reactor configuration on biogas production from wheat straw hydrolysate.  

PubMed

The potential of wheat straw hydrolysate for biogas production was investigated in continuous stirred tank reactor (CSTR) and up-flow anaerobic sludge bed (UASB) reactors. The hydrolysate originated as a side stream from a pilot plant pretreating wheat straw hydrothermally (195 degrees C for 10-12 min) for producing 2nd generation bioethanol [Kaparaju, P., Serrano, M., Thomsen, A.B., Kongjan, P., Angelidaki, I., 2009. Bioethanol, biohydrogen and biogas production from wheat straw in a biorefinery concept. Bioresource Technology 100 (9), 2562-2568]. Results from batch assays showed that hydrolysate had a methane potential of 384 ml/g-volatile solids (VS)(added). Process performance in CTSR and UASB reactors was investigated by varying hydrolysate concentration and/or organic loading rate (OLR). In CSTR, methane yields increased with increase in hydrolysate concentration and maximum yield of 297 ml/g-COD was obtained at an OLR of 1.9 g-COD/l d and 100% (v/v) hydrolysate. On the other hand, process performance and methane yields in UASB were affected by OLR and/or substrate concentration. Maximum methane yields of 267 ml/g-COD (COD removal of 72%) was obtained in UASB reactor when operated at an OLR of 2.8 g-COD/l d but with only 10% (v/v) hydrolysate. However, co-digestion of hydrolysate with pig manure (1:3 v/v ratio) improved the process performance and resulted in methane yield of 219 ml/g-COD (COD removal of 72%). Thus, anaerobic digestion of hydrolysate for biogas production was feasible in both CSTR and UASB reactor types. However, biogas process was affected by the reactor type and operating conditions. PMID:19647428

Kaparaju, Prasad; Serrano, María; Angelidaki, Irini

2009-12-01

236

Sulfuric Acid Hydrolysis and Detoxification of Red Alga Pterocladiella capillacea for Bioethanol Fermentation with Thermotolerant Yeast Kluyveromyces marxianus.  

PubMed

One-step sulfuric acid saccharification of the red alga Pterocladiella capillacea was optimized, and various detoxification methods (neutralization, overliming, and electrodialysis) of the acid hydrolysate were evaluated for fermentation with the thermotolerant yeast Kluyveromyces marxianus. A proximate composition analysis indicated that P. capillacea was rich in carbohydrates. A significant galactose recovery of 81.1 ± 5% was also achieved under the conditions of a 12% (w/v) biomass load, 5% (v/v) sulfuric acid, 121°C, and hydrolysis for 30 min. Among the various detoxification methods, electrodialysis was identified as the most suitable for fermentable sugar recovery and organic acid removal (100% reduction of formic and levulinic acids), even though it failed to reduce the amount of the inhibitor 5-HMF. As a result, K. marxianus fermentation with the electrodialyzed acid hydrolysate of P. capillacea resulted in the best ethanol levels and fermentation efficiency. PMID:24851812

Wu, Chien-Hui; Chien, Wei-Chen; Chou, Han-Kai; Yang, Jungwoo; Lin, Hong-Ting Victor

2014-09-28

237

Evaluation of Physicochemical and Antioxidant Properties of Peanut Protein Hydrolysate  

PubMed Central

Peanut protein and its hydrolysate were compared with a view to their use as food additives. The effects of pH, temperature and protein concentration on some of their key physicochemical properties were investigated. Compared with peanut protein, peanut peptides exhibited a significantly higher solubility and significantly lower turbidity at pH values 2–12 and temperature between 30 and 80°C. Peanut peptide showed better emulsifying capacity, foam capacity and foam stability, but had lower water holding and fat adsorption capacities over a wide range of protein concentrations (2–5 g/100 ml) than peanut protein isolate. In addition, peanut peptide exhibited in vitro antioxidant properties measured in terms of reducing power, scavenging of hydroxyl radical, and scavenging of DPPH radical. These results suggest that peanut peptide appeared to have better functional and antioxidant properties and hence has a good potential as a food additive. PMID:22693580

Zhang, Hui Cui; Zhang, Chu Shu; Yu, Li Na; Bi, Jie; Zhu, Feng; Liu, Shao Fang; Yang, Qing Li

2012-01-01

238

[Short peptide fragments with antiulcer activity from a collagen hydrolysate].  

PubMed

A peptide acidic hydrolysate of collagen (PHC) was obtained under conditions (4 N HCl) ensuring the predominant formation of short peptides, glyprolines. They were separated and their antiulcer activity was studied. Thirty individual peptides with molecular masses of 174-420 amu were isolated from the PHC by HPLC. The PHC was shown to predominantly contain 2- to 4-aa peptides, including PG, GP, and PGP. Experiments on rats demonstrated that, on intragastric administration at a dose of 1 mg/kg, PHC enhances the stability of the gastric mucosa to the action of ulcerogenic factors, such as ethanol and stress, and exhibits a protecting antiulcer effect. Even a lesser dose (0.1 mg/kg), which reduced ulcer area twofold, was effective in the stress model of ulcer formation. The intraperitoneal and intragastric administration of PHC at a dose of 1 mg/kg was found to exhibit a therapeutic effect in the acetate model of ulcer formation. PMID:16637291

Zolotarev, Iu A; Badmaeva, K E; Bakaeva, Z V; Samonina, G E; Kopylova, G N; Dadaian, A K; Zverkov, Iu B; Garanin, S K; Vas'kovski?, B V; Ashmarin, I P; Miasoedov, N F

2006-01-01

239

Wheat gluten hydrolysate affects race performance in the triathlon  

PubMed Central

Wheat gluten hydrolysate (WGH) is a food ingredient, prepared by partial enzymatic digestion of wheat gluten, which has been reported to suppress exercise-induced elevation of serum creatinine kinase (CK) activity. However, its effects on athletic performance have not yet been elucidated. This is the presentation of an experiment performed on five female college triathletes who completed an Olympic distance triathlon with or without ingestion of 21 g of WGH during the cycling leg. The experiment was performed in a crossover double-blind manner. The race time of the running leg and thus the total race time was significantly shorter when WGH was ingested. However, serum CK levels exhibited no apparent differences between the two WGH or placebo groups. PMID:24649002

KOIKAWA, NATSUE; AOKI, EMI; SUZUKI, YOSHIO; SAKURABA, KEISHOKU; NAGAOKA, ISAO; AOKI, KAZUHIRO; SHIMMURA, YUKI; SAWAKI, KEISUKE

2013-01-01

240

Wood hydrolysate barriers: performance controlled via selective recovery.  

PubMed

Films and coatings were produced from a noncellulosic polysaccharide-rich wood hydrolysate (WH), and the resulting oxygen barrier performance was improved by a selective choice of upgrading conditions. The WH was obtained from process water in the hydrothermal treatment of hardwood and subjected to one of three alternative upgrading treatments, resulting in xylan-rich fractions with significant differences in structure, composition, and properties of the recovered WH fractions, which in turn had a major impact on their performance with respect to tensile and oxygen barrier properties. The WH in the least upgraded state, the crudest fraction, produced films with the best performance in terms of oxygen permeability and was superior to corresponding films based on highly purified hemicellulose. PMID:22181657

Ibn Yaich, Anas; Edlund, Ulrica; Albertsson, Ann-Christine

2012-02-13

241

Comparative study of the physiological properties of collagen, gelatin and collagen hydrolysate as cosmetic materials.  

PubMed

The cell biological properties of collagen, gelatin and collagen hydrolysate (<15 000 Da) were studied using murine keratinocytes. Keratinocyte culture experiments demonstrated that only collagen had significant effects on cell attachment and proliferation, but the results of cells cultured on gelatin and collagen hydrolysate showed the rates of adhesion and proliferation were similar to those of cells cultured on plastic as a control. It is concluded that collagen has better physiological effects than those of gelatin and collagen hydrolysate as skin-care cosmetic materials. PMID:18492159

Li, G Y; Fukunaga, S; Takenouchi, K; Nakamura, F

2005-04-01

242

[Effectiveness of parenteral feeding with various hydrolysates in alloxan diabetes in white rats].  

PubMed

The effect of applying various hydrolysates for parenteral feeding (caseine hydrolysate, hydrolysin L-103, aminosol, moriamine S-2) in albino rats with alloxan-induced diabetes was investigated. The assimilation of the hydrolysates introduced was found in these animals to be down by comparison with intact ones. It was only administration of nitrogenous media containing a sufficient amount of aminic nitrogen (moriamine S-2) that helped establish a positive nitrogenous balance and to prevent a loss of weight and the dry weight of the tissues. PMID:808036

Glants, R M; Skovronskaia, E V; Vovk, G P

1975-01-01

243

Collagen hydrolysate intake increases skin collagen expression and suppresses matrix metalloproteinase 2 activity.  

PubMed

The effect of daily ingestion of collagen hydrolysate (CH) on skin extracellular matrix proteins was investigated. Four-week-old male Wistar rats were fed a modified AIN-93 diet containing 12% casein as the reference group or CH as the treatment group. A control group was established in which animals were fed a non-protein-modified AIN-93 diet. The diets were administered continuously for 4 weeks when six fresh skin samples from each group were assembled and subjected to extraction of protein. Type I and IV collagens were studied by immunoblot, and activities of matrix metalloproteinase (MMP) 2 and 9 were assessed by zymography. The relative amount of type I and IV collagens was significantly (P?

Zague, Vivian; de Freitas, Vanessa; da Costa Rosa, Marina; de Castro, Geórgia Álvares; Jaeger, Ruy G; Machado-Santelli, Gláucia M

2011-06-01

244

Effect of agitation rate on ethanol production from sugar maple hemicellulosic hydrolysate by Pichia stipitis.  

PubMed

Concentrated dilute acid hydrolysate was obtained from hot water extracts of Acer saccharum (sugar maple) and was fermented to ethanol by Pichia stipitis in a 1.3-L-benchtop bioreactor. The conditions under which the highest ethanol yield was achieved were when the air flow rate was set to 100 cm(3) and the agitation rate was set to 150 rpm resulting in an overall mass transfer coefficient (K(L)a) of 0.108 min(-1). A maximum ethanol concentration of 29.7 g/L was achieved after 120 h of fermentation; however, after 90 h of fermentation, the ethanol concentration was only slightly lower at 29.1 g/L with a yield of 0.39 g ethanol per gram of sugar consumed. Using the same air flow rate and adjusting the agitation rate resulted in lower ethanol yields of 0.25 g/g at 50 rpm and 0.30 g/g at 300 rpm. The time it takes to reach the maximum ethanol concentration was also affected by the agitation rate. The ethanol concentration continued to increase even after 130 h of fermentation when the agitation rate was set at 50 rpm, whereas the maximum ethanol concentration was reached after only 68.5 h at 300 rpm. PMID:21603950

Shupe, Alan M; Liu, Shijie

2012-09-01

245

Amino Acid Analyses of Acid Hydrolysates in Desert Varnish  

NASA Technical Reports Server (NTRS)

There has long been a debate as to whether rock varnish deposits are microbially mediated or are deposited by inorganic processes. Varnished rocks are found throughout the world primarily in arid and semi-arid regions. The varnish coats are typically up to 200 microns thick and are composed of clays and alternating layers enriched in manganese and iron oxides. The individual layers range in thickness from 1 micron to greater than 10 microns and may continue laterally for more than a 100 microns. Overlapping botryoidal structures are visible in thin section and scanning electron micrographs. The coatings also include small amounts of organic mater and detrital grains. Amino-acid hydrolysates offer a means of assessing the organic composition of rock varnish collected from the Sonoran Desert, near Phoenix, AZ. Chromatographic analyses of hydrolysates from powdered samples of rock varnish suggest that the interior of rock varnish is relatively enriched in amino acids and specifically in d-alanine and glutamic acid. Peptidoglycan (murein) is the main structural component of gram-positive bacterial cell walls. The d-enantiomer of alanine and glutamic acid are specific to peptidoglycan and are consequently an indicator for the presence of bacteria. D-alanine is also found in teichoic acid which is only found in gram-positive bacteria. Several researchers have cultured bacteria from the surface of rock varnish and most have been gram-positive, suggesting that gram-positive bacteria are intimately associated with varnish coatings and may play a role in the formation of varnish coatings.

Perry, Randall S.; Staley, James T.; Dworkin, Jason P.; Engel, Mike

2001-01-01

246

Effects of collagen and collagen hydrolysate from jellyfish umbrella on histological and immunity changes of mice photoaging.  

PubMed

Jellyfish collagen (JC) was extracted from jellyfish umbrella and hydrolyzed to prepare jellyfish collagen hydrolysate (JCH). The effects of JC and JCH on UV-induced skin damage of mice were evaluated by the skin moisture, microscopic analyses of skin and immunity indexes. The skin moisture analyses showed that moisture retention ability of UV-induced mice skin was increased by JC and JCH. Further histological analysis showed that JC and JCH could repair the endogenous collagen and elastin protein fibers, and could maintain the natural ratio of type I to type III collagen. The immunity indexes showed that JC and JCH play a role in enhancing immunity of photoaging mice in vivo. JCH showed much higher protective ability than JC. These results suggest that JCH as a potential novel antiphotoaging agent from natural resources. PMID:23344251

Fan, Jian; Zhuang, Yongliang; Li, Bafang

2013-01-01

247

Effects of collagen and collagen hydrolysate from jellyfish (Rhopilema esculentum) on mice skin photoaging induced by UV irradiation.  

PubMed

Collagen (JC) was extracted from jellyfish (Rhopilema esculentum) and hydrolyzed to prepare collagen hydrolysate (JCH). The protective effects of JC and JCH against UV-induced damages to mice skin were evaluated and compared in this article. JC and JCH could alleviate the UV-induced abnormal changes of antioxidative indicators, including the superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and catalase (CAT) activities and the contents of glutathione (GSH) and malondiaidehyde (MDA). JC and JCH could protect skin lipid and collagen from the UV radiation damages. Furthermore, the changes of total ceramide and glycosaminoglycan in skin were recovered significantly by JC and JCH. The action mechanisms mainly involved the antioxidative properties and the repairing to endogenous collagen synthesis of JC and JCH in vivo. JCH with the lower molecular weight showed much higher effects than JC. The results indicated that JCH was a novel antiphotoaging agent from natural resources. PMID:19723203

Zhuang, Yongliang; Hou, Hu; Zhao, Xue; Zhang, Zhaohui; Li, Bafang

2009-08-01

248

Effects of Collagen and Collagen Hydrolysate from Jellyfish Umbrella on Histological and Immunity Changes of Mice Photoaging  

PubMed Central

Jellyfish collagen (JC) was extracted from jellyfish umbrella and hydrolyzed to prepare jellyfish collagen hydrolysate (JCH). The effects of JC and JCH on UV-induced skin damage of mice were evaluated by the skin moisture, microscopic analyses of skin and immunity indexes. The skin moisture analyses showed that moisture retention ability of UV-induced mice skin was increased by JC and JCH. Further histological analysis showed that JC and JCH could repair the endogenous collagen and elastin protein fibers, and could maintain the natural ratio of type I to type III collagen. The immunity indexes showed that JC and JCH play a role in enhancing immunity of photoaging mice in vivo. JCH showed much higher protective ability than JC. These results suggest that JCH as a potential novel antiphotoaging agent from natural resources. PMID:23344251

Fan, Jian; Zhuang, Yongliang; Li, Bafang

2013-01-01

249

Simple and sensitive method for quantification of fluorescent enzymatic mature and senescent crosslinks of collagen in bone hydrolysate using single-column high performance liquid chromatography.  

PubMed

A rapid high performance liquid chromatographic method was developed including an internal standard for the measurement of mature and senescent crosslinks concentration in non-demineralized bone hydrolysates. To avoid the demineralization which is a tedious step, we developed a method based on the use of a solid-phase extraction procedure to clean-up the samples. It resulted in sensitive and accurate measurements: the detection limits as low as 0.2 pmol for the pyridimium crosslinks and 0.02 pmol for the pentosidine. The inter- and intra-assay coefficients of variation were as low as 5% and 2%, respectively, for all crosslinks. PMID:19027371

Viguet-Carrin, S; Gineyts, E; Bertholon, C; Delmas, P D

2009-01-01

250

Improved bioethanol production using fusants of Saccharomyces cerevisiae and xylose-fermenting yeasts.  

PubMed

The present research deals with the development of a hybrid yeast strain with the aim of converting pentose and hexose sugar components of lignocellulosic substrate to bioethanol by fermentation. Different fusant strains were obtained by fusing protoplasts of Saccharomyces cerevisiae and xylose-fermenting yeasts such as Pachysolen tannophilus, Candida shehatae and Pichia stipitis. The fusants were sorted by fluorescent-activated cell sorter and further confirmed by molecular characterization. The fusants were evaluated by fermentation of glucose-xylose mixture and the highest ethanol producing fusant was used for further study to ferment hydrolysates produced by acid pretreatment and enzymatic hydrolysis of cotton gin waste. Among the various fusant and parental strains used under present study, RPR39 was found to be stable and most efficient strain giving maximum ethanol concentration (76.8 ± 0.31 g L(-1)), ethanol productivity (1.06 g L(-1) h(-1)) and ethanol yield (0.458 g g(-1)) by fermentation of glucose-xylose mixture under test conditions. The fusant has also shown encouraging result in fermenting hydrolysates of cotton gin waste with ethanol concentration of 7.08 ± 0.142 g L(-1), ethanol yield of 0.44 g g(-1), productivity of 0.45 g L(-1) h(-1) and biomass yield of 0.40 g g(-1). PMID:22639357

Kumari, Rajni; Pramanik, K

2012-06-01

251

Ethanol production from marine algal hydrolysates using Escherichia coli KO11.  

PubMed

Algae biomass is a potential raw material for the production of biofuels and other chemicals. In this study, biomass of the marine algae, Ulva lactuca, Gelidium amansii,Laminaria japonica, and Sargassum fulvellum, was treated with acid and commercially available hydrolytic enzymes. The hydrolysates contained glucose, mannose, galactose, and mannitol, among other sugars, at different ratios. The Laminaria japonica hydrolysate contained up to 30.5% mannitol and 6.98% glucose in the hydrolysate solids. Ethanogenic recombinant Escherichia coli KO11 was able to utilize both mannitol and glucose and produced 0.4g ethanol per g of carbohydrate when cultured in L. japonica hydrolysate supplemented with Luria-Bertani medium and hydrolytic enzymes. The strategy of acid hydrolysis followed by simultaneous enzyme treatment and inoculation with E. coli KO11 could be a viable strategy to produce ethanol from marine alga biomass. PMID:21640583

Kim, Nag-Jong; Li, Hui; Jung, Kwonsu; Chang, Ho Nam; Lee, Pyung Cheon

2011-08-01

252

DIGESTION OF PARTIALLY HYDROLYSED STARCH IN MILK REPLACERS BY THE YOUNG LAMB  

E-print Network

% of partially pre-digested starch (protamyl 1001, 33, 27 and 22 % of butter fat, and 37, 35, 34 % casein preruminant lambs to hydrolyse large amounts of starch when the physical structure of this carbohydrate

Paris-Sud XI, Université de

253

An integrated detoxification process with electrodialysis and adsorption from the hemicellulose hydrolysates of yellow poplars.  

PubMed

An integrated detoxification process with electrodialysis (ED) followed by adsorption was performed to remove fermentation inhibitors from hemicellulose hydrolysates. The hydrolysates were prepared by oxalic acid pretreatment of yellow poplars at different temperatures. Of fermentation inhibitors, acetic acid showed high removal efficiency of about 90% and high transport rate during the ED process without membrane fouling. The integration of the detoxification processes increased up to the ethanol yield of 0.33g/g sugar, the ethanol production of about 9g/L, and the productivity of 0.12g/Lh, while the fermentation of non-detoxified hydrolysates did not produce bioethanol. The influence of inhibitor concentration on the fermentability showed that HMF had the highest inhibition effect. The results clearly showed that an integrated detoxification process with ED followed by adsorption removed fermentation inhibitors with high efficiency and increased the fermentability of the oxalic acid pretreated hemicellulose hydrolysates. PMID:24713602

Trinh, Ly Thi Phi; Kundu, Chandan; Lee, Jae-Won; Lee, Hong-Joo

2014-06-01

254

Pretreatment of sugarcane bagasse hemicellulose hydrolysate for xylitol production by Candida guilliermondii  

Microsoft Academic Search

In order to remove or reduce the concentrations of toxic substances present in the sugarcane bagasse hemicellulose hydrolysate\\u000a for xyloseto-xylitol bioconversion, the hydrolysate was pretreated by changing the initial pH level through the combination\\u000a of different bases and acids with or without the subsequent addition of activated charcoal. Attention was given to the influence\\u000a of the fermentation time as well.

Lourdes A. Alves; Maria G. A. Felipe; JoÃo B. Almeida E. Silva; Silvio S. Silva; Arnaldo M. R. Prata

1998-01-01

255

Detoxification of sugarcane bagasse hydrolysate improves ethanol production by Candida shehatae NCIM 3501  

Microsoft Academic Search

Sugarcane bagasse hydrolysis with 2.5% (v\\/v) HCl yielded 30.29g\\/L total reducing sugars along with various fermentation inhibitors such as furans, phenolics and acetic acid. The acid hydrolysate when treated with anion exchange resin brought about maximum reduction in furans (63.4%) and total phenolics (75.8%). Treatment of hydrolysate with activated charcoal caused 38.7% and 57.5% reduction in furans and total phenolics,

Anuj Kumar Chandel; Rajeev Kumar Kapoor; Ajay Singh; Ramesh Chander Kuhad

2007-01-01

256

Mechanism of the inhibition of calmodulin-dependent neuronal nitric oxide synthase by flaxseed protein hydrolysates  

Microsoft Academic Search

This work was aimed at producing potential nutraceutical peptides from flaxseed protein hydrolysate that can bind to calmodulin\\u000a (CaM) and inhibit the activity of CaM-dependent neuronal nitric oxide synthase (nNOS), an enzyme that has been implicated\\u000a in some forms of human diseases. Flaxseed protein isolate was hydrolyzed with alcalase, and the resultant protein hydrolysate\\u000a was passed through a 1000-Da M.W.

Adetayo O. Omoni; Rotimi E. Aluko

2006-01-01

257

Tobacco biomass hydrolysate enhances coenzyme Q10 production using photosynthetic Rhodospirillum rubrum  

Microsoft Academic Search

Coenzyme Q10 (CoQ10), a potent antioxidative dietary supplement, was produced using a photosynthetic bacteria Rhodospirillum rubrum ATCC 25852 by submerged fermentation supplemented with tobacco biomass hydrolysate (TBH) in comparison with media supplemented with hydrolysates prepared with alfalfa (ABH) or spinach (SBH). Growth medium supplemented with 20% (v\\/v) TBH was found favorable with regard to cell density and CoQ10 concentration. The

Yuting Tian; Tianli Yue; Yahong Yuan; Pavan K. Soma; Patrick D. Williams; Peter A. Machado; Hong Fu; Robert J. Kratochvil; Cheng-i Wei; Y. Martin Lo

2010-01-01

258

Process design and economic analysis of a ceramic membrane system for microfiltration of corn starch hydrolysate  

Microsoft Academic Search

A ceramic microfiltration membrane was used for the clarification of 95 dextrose equivalence corn starch hydrolysate. Fluxes were optimized for transmembrane pressure and cross-flow velocity at various feed concentration ratios. A microfiltration membrane plant was designed for clarification of 113.6 m3 h?1 (500 gal min?1) of corn starch hydrolysate. The optimum membrane plant would have two feed-and-bleed stages with an

Navpreet Singh; Munir Cheryan

1998-01-01

259

Effect of reactor configuration on biogas production from wheat straw hydrolysate  

Microsoft Academic Search

The potential of wheat straw hydrolysate for biogas production was investigated in continuous stirred tank reactor (CSTR) and up-flow anaerobic sludge bed (UASB) reactors. The hydrolysate originated as a side stream from a pilot plant pretreating wheat straw hydrothermally (195°C for 10–12min) for producing 2nd generation bioethanol [Kaparaju, P., Serrano, M., Thomsen, A.B., Kongjan, P., Angelidaki, I., 2009. Bioethanol, biohydrogen

Prasad Kaparaju; María Serrano; Irini Angelidaki

2009-01-01

260

An In-vitro Investigation of Selected Biological Activities of Hydrolysed Flaxseed ( Linum usitatissimum L.) Proteins  

Microsoft Academic Search

A study was conducted to determine bioactivities of flaxseed (Linum usitatissimum L.; variety: Valour) proteins and their hydrolysates. Isolated flaxseed proteins were treated with Flavourzyme® at different levels of enzyme to substrate ratio (E\\/S) and hydrolysis time. The unhydrolysed proteins and hydrolysates were\\u000a studied for angiotensin I-converting enzyme inhibiting (ACEI) activity, hydroxyl radical (OH·) scavenging activity and bile\\u000a acid binding

P. W. M. L. H. K. Marambe; P. J. Shand; J. P. D. Wanasundara

2008-01-01

261

Influence of molecular interactions on ultrafiltration of a bovine hemoglobin hydrolysate with an organic membrane  

Microsoft Academic Search

Inter-molecular interactions involved in the hydrolysate were studied in order to explain heme and peptide high retentions observed during the ultrafiltration of a bovine hemoglobin peptidic hydrolysate with a 10kDa modified polyethersulfone membrane.Physico-chemical properties of the peptidic fractions of the retentate and of the permeate were characterized by UV\\/vis spectroscopy, SDS-PAGE electrophoresis, size-exclusion chromatography, reversed phase HPLC, hydrophobic interaction chromatography

F Lebrun; A Bazus; P Dhulster; D Guillochon

1998-01-01

262

Amino acid composition and functional properties of giant red sea cucumber ( Parastichopus californicus ) collagen hydrolysates  

Microsoft Academic Search

Giant red sea cucumber (Parastichopus californicus) is an under-utilized species due to its high tendency to autolysis. The aim of this study was to evaluate the functional\\u000a properties of collagen hydrolysates from this species. The degree of hydrolysis (DH), amino acid composition, SDS-PAGE, emulsion\\u000a activity index (EAI), emulsion stability index (ESI), foam expansion (FE), and foam stability (FS) of hydrolysates

Zunying Liu; Yicheng Su; Mingyong Zeng

2011-01-01

263

Effect of defatting and enzyme type on antioxidative activity of shrimp processing byproducts hydrolysate  

Microsoft Academic Search

Shrimp processing byproducts (SPB) was digested by 6 proteases (trypsin, pepsin, neutrase, Protamex, Flavourzyme, and Alcalase)\\u000a to produce antioxidative peptides. Both degree of hydrolysis (DH) and DPPH radical scavenging activity (DSA) of the Alcalase\\u000a hydrolysate were the highest of all. The effect of defatting on DH and DSA of the Alcalase hydrolysate was significant. The\\u000a DH decreased while the DSA

Guang-Rong Huang; Jing Zhao; Jia-Xin Jiang

2011-01-01

264

Interactions between yeast lees and wine polyphenols during simulation of wine aging. II. Analysis of desorbed polyphenol compounds from yeast lees.  

PubMed

In the first part of this work, the analysis of the polyphenolic compounds remaining in the wine after different contact times with yeast lees during simulation of red wine aging was undertaken. To achieve a more precise view of the wine polyphenols adsorbed on lees during red wine aging and to establish a clear balance between adsorbed and remnant polyphenol compounds, the specific analysis of the chemical composition of the adsorbed polyphenolic compounds (condensed tannins and anthocyanins) after their partial desorbtion from yeast lees by denaturation treatments was realized in the second part of the study. The total recovery of polyphenol compounds from yeast lees was not complete, since a rather important part of the initial wine colored polyphenols, especially those with a dominant blue color component, remained strongly adsorbed on yeast lees, as monitored by color tristimulus and reflectance spectra measurements. All anthocyanins were recovered at a rather high percentage (about 62%), and it was demonstrated that they were not adsorbed in relation with their sole polarity. Very few monomeric phenolic compounds were extracted from yeast lees. With the use of drastic denaturing treatments, the total recovery of condensed tannins reached 83%. Such tannins extracted from yeast lees exhibited very high polymeric size and a rather high percentage of galloylated residues by comparison with initial wine tannins, indicating that nonpolar tannins were preferentially desorbed from yeast lees by the extraction treatments. PMID:16719509

Mazauric, Jean-Paul; Salmon, Jean-Michel

2006-05-31

265

In Vitro Binding Capacity of Bile Acids by Defatted Corn Protein Hydrolysate  

PubMed Central

Defatted corn protein was digested using five different proteases, Alcalase, Trypsin, Neutrase, Protamex and Flavourzyme, in order to produce bile acid binding peptides. Bile acid binding capacity was analyzed in vitro using peptides from different proteases of defatted corn hydrolysate. Some crystalline bile acids like sodium glycocholate, sodium cholate and sodium deoxycholate were individually tested using HPLC to see which enzymes can release more peptides with high bile acid binding capacity. Peptides from Flavourzyme defatted corn hydrolysate exhibited significantly (p < 0.05) stronger bile acid binding capacity than all others hydrolysates tested and all crystalline bile acids tested were highly bound by cholestyramine, a positive control well known as a cholesterol-reducing agent. The bile acid binding capacity of Flavourzyme hydrolysate was almost preserved after gastrointestinal proteases digestion. The molecular weight of Flavourzyme hydrolysate was determined and most of the peptides were found between 500–180 Da. The results showed that Flavourzyme hydrolysate may be used as a potential cholesterol-reducing agent. PMID:21541043

Kongo-Dia-Moukala, Jauricque Ursulla; Zhang, Hui; Irakoze, Pierre Claver

2011-01-01

266

Improvement of the fermentability of oxalic acid hydrolysates by detoxification using electrodialysis and adsorption.  

PubMed

A two-step detoxification process consisting of electrodialysis and adsorption was performed to improve the fermentability of oxalic acid hydrolysates. The constituents of the hydrolysate differed significantly between mixed hardwood and softwood. Acetic acid and furfural concentrations were high in the mixed hardwood, whereas 5-hydroxymethylfurfural (HMF) concentration was relatively low compared with that of the mixed softwood. The removal efficiency of acetic acid reached 100% by electrodialysis (ED) process in both hydrolysates, while those of furfural and HMF showed very low, due to non-ionizable properties. Most of the remaining inhibitors were removed by XAD-4 resin. In the mixed hardwood hydrolysate without removal of the inhibitors, ethanol fermentation was not completed. Meanwhile, both ED-treated hydrolysates successfully produced ethanol with 0.08 and 0.15 g/Lh ethanol productivity, respectively. The maximum ethanol productivity was attained after fermentation with 0.27 and 0.35 g/Lh of detoxified hydrolysates, which were treated by ED, followed by XAD-4 resin. PMID:24321607

Jeong, So-Yeon; Trinh, Ly Thi Phi; Lee, Hong-Joo; Lee, Jae-Won

2014-01-01

267

Succinic acid production from corn cob hydrolysates by genetically engineered Corynebacterium glutamicum.  

PubMed

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. PMID:24078255

Wang, Chen; Zhang, Hengli; Cai, Heng; Zhou, Zhihui; Chen, Yilu; Chen, Yali; Ouyang, Pingkai

2014-01-01

268

Antioxidative and functional properties of protein hydrolysate from defatted skipjack (Katsuwonous pelamis) roe.  

PubMed

Antioxidative and functional properties of protein hydrolysate from defatted skipjack (Katsuwonous pelamis) roe, hydrolysed by Alcalase 2.4 L (RPH) with different degrees of hydrolysis (DH) at various concentrations were examined. As DH increased, the reduction of DPPH, ABTS radicals scavenging activities and reducing power were noticeable (p<0.05). The increases in metal chelating activity and superoxide scavenging activity were attained with increasing DH (p<0.05). However, chelating activity gradually decreased at DH above 30%. All activities except superoxide anion radical scavenging activity increased as the concentration of hydrolysate increased (p<0.05). Hydrolysis using Alcalase could increase protein solubility to above 80% over a wide pH range (2-10). The highest emulsion ability index (EAI) and foam stability (FS) of hydrolysates were observed at low DH (5%) (p<0.05). Concentrations of hydrolysates determined interfacial properties differently, depending on DH. The molecular weight distribution of RPH with 5%DH (RPH5) was determined using Sephadex G-75 column. Two major peaks with the molecular weight of 57.8 and 5.5kDa were obtained. Fraction with MW of 5.5 had the strongest metal chelating activity and ABTS radical scavenging activity. The results reveal that protein hydrolysates from defatted skipjack roe could be used as food additives possessing both antioxidant activity and functional properties. PMID:22980906

Intarasirisawat, Rossawan; Benjakul, Soottawat; Visessanguan, Wonnop; Wu, Jianping

2012-12-15

269

Physicochemical and sensory characteristics of whey protein hydrolysates generated at different total solids levels.  

PubMed

Whey protein hydrolysates were generated at different total solids (TS) levels (50-300 g/l) using the commercially available proteolytic preparation Debitrase HYW20, while enzyme to substrate ratio, pH and temperature were maintained constant. Hydrolysis proceeded at a faster rate at lower TS reaching a degree of hydrolysis (DH) of 16.6% at 300 g TS/l, compared with a DH of 22.7% at 50 g TS/l after 6 h hydrolysis. The slower breakdown of intact whey proteins at high TS was quantified by gel-permeation HPLC. Reversed-phase (RP) HPLC of hydrolysate samples of equivalent DH (approximately 15%) generated at different TS levels indicated that certain hydrophobic peptide peaks were present at higher levels in hydrolysates generated at low TS. Sensory evaluation showed that hydrolysates with equivalent DH values were significantly (P < 0.0005) less bitter when generated at 300 g TS/l (mean bitterness score = 25.4%) than hydrolysates generated at 50 g TS/l (mean bitterness score = 39.9%). A specific hydrophobic peptide peak present at higher concentrations in hydrolysates generated at low TS was isolated and identified as beta-lactoglobulin f(43-57), a fragment having the physical and chemical characteristics of a bitter peptide. PMID:15909678

Spellman, David; O'Cuinn, Gerard; FitzGerald, Richard J

2005-05-01

270

Extracellular Polysaccharides Produced by Yeasts and Yeast-Like Fungi  

NASA Astrophysics Data System (ADS)

Several yeasts and yeast-like fungi are known to produce extracellular polysaccharides. Most of these contain D-mannose, either alone or in combination with other sugars or phosphate. A large chemical and structural variability is found between yeast species and even among different strains. The types of polymers that are synthesized can be chemically characterized as mannans, glucans, phosphoman-nans, galactomannans, glucomannans and glucuronoxylomannans. Despite these differences, almost all of the yeast exopolysaccharides display some sort of biological activity. Some of them have already applications in chemistry, pharmacy, cosmetics or as probiotic. Furthermore, some yeast exopolysaccharides, such as pullulan, exhibit specific physico-chemical and rheological properties, making them useful in a wide range of technical applications. A survey is given here of the production, the characteristics and the application potential of currently well studied yeast extracellular polysaccharides.

van Bogaert, Inge N. A.; de Maeseneire, Sofie L.; Vandamme, Erick J.

271

Production of alcohol from Jerusalem artichokes by yeasts  

SciTech Connect

Various yeasts such as several strains of Saccharomyces diastaticus, S. cerevisiae, and Kluyveromyces fragilis were investigated for their ability to ferment the carbohydrates from Jerusalem artichokes to alcohol. Juice extracted from the artichokes was used as the fermentation substrate with and without prior hydrolysis of the carbohydrates. Fermentation was also carried out with raw artichokes without prior juice extraction. Results indicate that this raw material has good potential for fuel alcohol production by fermentation. (Refs. 15).

Duvnjak, Z.; Kosaric, N.; Kliza, S.; Hayes, D.

1982-11-01

272

Derepression of galactose metabolism in melibiase producing bakers' and distillers' yeast.  

PubMed

Beet molasses is widely used as a growth substrate for bakers' and distillers' yeast in the production of biomass and ethanol. Most commercial yeasts do not fully utilise the carbohydrates in molasses since they are incapable of hydrolysing the disaccharide melibiose to glucose and galactose. Also, expression of genes encoding enzymes for the utilisation of carbon sources that are alternatives to glucose is tightly regulated, sometimes rates of yeast growth and/or ethanol production. The GAL genes are regulated by specific induction by galactose and repression during growth on glucose. In an industrial distillers' yeast, two genes interacting synergistically in glucose repression of galactose utilization, MIG1 and GAL80, have been disrupted with MEL1, encoding melibiase. The physiology of the wild-type strain and the recombinant strains was investigated on mixtures of glucose and galactose and on molasses. The recombinant strain started to ferment galactose when 9.7 g 1(-1) glucose was still present during a batch fermentation, whereas the wild-type strain did not consume any galactose in the presence of glucose. The ethanol yield in the recombinant strain was 0.50 g ethanol g sugar (-1) in an ethanol fermentation on molasses, compared with 0.48 g ethanol g sugar (-1) for the wild-type strain. The increased ethanol yield was due to utilization of melibiose in the molasses. PMID:12680392

Rønnow, B; Olsson, L; Nielsen, J; Mikkelsen, J D

1999-06-11

273

Process development of fuel ethanol production from lignocellulosic sugars using gentically engineered yeasts  

SciTech Connect

Lignocellulosic biomass is an ideal feedstock for the large scale manufacture of fuel ethanol. Glucose and xylose represent the two major fermentable sugars in lignocellulosic hydrolysates and efficient fermentation of both these sugars is essential for the economical production of fuel ethanol. In our laboratory, a genetically engineered yeast 1400 (pLNH33) has been developed which can ferment glucose and xylose simultaneously to ethanol. This recombinant yeast has a very high ethanol tolerance (13.6% w/v) which allows high ethanol concentrations to accumulate in the fermentation medium, thus reducing downstream processing mu significantly. For large scale application of this genetically engineered cell culture, the fermentation kinetics have been investigated. We have studied the effects of substrate and product inhibition for both the host post 1400 and the engineered yeast 1400 (pLNH33) during fermentation of glucose, xylose and mixtures of glucose and xylose. Plasmid instability is an important factor influencing cell culture scale up. This aspect w investigated in selective, non-selective and partially selective fermentation media and the results will be reported in this paper. Based on these kinetic studies, a model has been developed which can simulate the fermentation of glucose and xylose to ethanol using the genetically engineered yeast 1400 (pLNH33), in both batch and continuous cultures.

Krishnan, M.S.; Xia, Y.; Ho, N.W.Y. [Purdue Univ., West Lafayette, IN (United States)] [and others

1996-10-01

274

Glyoxalase system in yeasts: structure, function, and physiology.  

PubMed

The glyoxalase system consists of glyoxalase I and glyoxalase II. Glyoxalase I catalyzes the conversion of methylglyoxal (CH(3)COCHO), a metabolite derived from glycolysis, with glutathione to S-D-lactoylglutathione, while glyoxalase II hydrolyses this glutathione thiolester to D-lactic acid and glutathione. Since methylglyoxal is toxic due to its high reactivity, the glyoxalase system is crucial to warrant the efficient metabolic flux of this reactive aldehyde. The budding yeast Saccharomyces cerevisiae has the sole gene (GLO1) encoding the structural gene for glyoxalase I. Meanwhile, this yeast has two isoforms of glyoxalase II encoded by GLO2 and GLO4. The expression of GLO1 is regulated by Hog1 mitogen-activated protein kinase and Msn2/Msn4 transcription factors under highly osmotic stress conditions. The physiological significance of GLO1 expression in response to osmotic stress is to combat the increase in the levels of methylglyoxal in cells during the production of glycerol as a compatible osmolyte. Deficiency in GLO1 in S. cerevisiae causes pleiotropic phenotypes in terms of stress response, because the steady state level of methylglyoxal increases in glo1? cells thereby constitutively activating Yap1 transcription factor. Yap1 is crucial for oxidative stress response, although methylglyoxal per se does not enhance the intracellular oxidation level in yeast, but it directly modifies cysteine residues of Yap1 that are critical for the nucleocytoplasmic localization of this b-ZIP transcription factor. Consequently, glyoxalase I can be defined as a negative regulator of Yap1 through modulating the intracellular methylglyoxal level. PMID:21310260

Inoue, Yoshiharu; Maeta, Kazuhiro; Nomura, Wataru

2011-05-01

275

[Protein utilization of mixed feed rations in lactating pigs with reference to the essential amino acid content of the feed proteins. 2. Report. Utilization of the feed proteins in the use of soy bean extraction residue, waste liquor yeast, horse bean meal fish meal and maize gluten for a basic ration].  

PubMed

Nitrogen trials were performed on lactating pigs to investigate the utilization of protein from some feeding rations. The basal ration fed to the sows consisted of ground barley+oats+flaked potatoes or ground barley+sugar beet chips. The basal ration was supplemented with a protein source. The protein feeds used were extracted soya bean meal, horse bean meal, fish meal, maize gluten and waste liquor yeast. Data for the average biological value of the dietary proteins were as follows (in the given order of protein feeds): 61%, 59%, 54%, 58% and 37%. PPV data were: 44%, 43%, 39%, 44% and 28%. The proteins of nearly all rations were deficient in lysine when compared with the range of amino acids present in the proteins of sow milk. PMID:1035091

Kracht, W; Hennig, A; Gruhn, K

1976-04-01

276

Yeast and Mammalian Metallothioneins Functionally Substitute for Yeast Copper-Zinc Superoxide Dismutase  

NASA Astrophysics Data System (ADS)

Copper-zinc superoxide dismutase catalyzes the disproportionation of superoxide anion to hydrogen peroxide and dioxygen and is thought to play an important role in protecting cells from oxygen toxicity. Saccharomyces cerevisiae strains lacking copper-zinc superoxide dismutase, which is encoded by the SOD1 gene, are sensitive to oxidative stress and exhibit a variety of growth defects including hypersensitivity to dioxygen and to superoxide-generating drugs such as paraquat. We have found that in addition to these known phenotypes, SOD1-deletion strains fail to grow on agar containing the respiratory carbon source lactate. We demonstrate here that expression of the yeast or monkey metallothionein proteins in the presence of copper suppresses the lactate growth defect and some other phenotypes associated with SOD1-deletion strains, indicating that copper metallothioneins substitute for copper-zinc superoxide dismutase in vivo to protect cells from oxygen toxicity. Consistent with these results, we show that yeast metallothionein mRNA levels are dramatically elevated under conditions of oxidative stress. Furthermore, in vitro assays demonstrate that yeast metallothionein, purified or from whole-cell extracts, exhibits copper-dependent antioxidant activity. Taken together, these data suggest that both yeast and mammalian metallothioneins may play a direct role in the cellular defense against oxidative stress by functioning as antioxidants.

Tamai, Katherine T.; Gralla, Edith B.; Ellerby, Lisa M.; Valentine, Joan S.; Thiele, Dennis J.

1993-09-01

277

Antimicrobial activity of extractives of Solidago microglossa  

Microsoft Academic Search

The antimicrobial activity of the methanol extract from Solidago microglossa roots, essential oil from its aerial part and some isolated compounds was investigated. The oil exhibited concentration-dependent activity against all the tested bacteria and yeasts.

A. F. Morel; G. O. Dias; C. Porto; E. Simionatto; C. Z. Stuker; I. I. Dalcol

2006-01-01

278

Yeast artificial chromosome cloning  

Microsoft Academic Search

Yeast artificial chromosome (YAC) cloning systems enable the cloning of DNA stretches of 50 to well over 2000 kb. This makes\\u000a it possible to study large intact regions of DNA in detail, by restriction mapping the YAC to produce a physical map and by\\u000a examining the YAC for coding sequences or genes. YACs are important for their ability to clone

Michele Ramsay

1994-01-01

279

Effects of Pro-Hyp, a collagen hydrolysate-derived peptide, on hyaluronic acid synthesis using in vitro cultured synovium cells and oral ingestion of collagen hydrolysates in a guinea pig model of osteoarthritis.  

PubMed

Proline-hydroxyproline (Pro-Hyp) stimulated hyaluronic acid production in cultured synovium cells. It was detected in guinea pig blood after oral ingestion of collagen hydrolysates. Oral administration of collagen hydrolysates increased the amount of proteoglycans in the epiphyses. It also reduced the morphological changes associated with osteoarthritic cartilage destruction of the knee joint. The results suggest that collagen hydrolysates have therapeutic potential for treatment of osteoarthritis. PMID:20944430

Ohara, Hiroki; Iida, Hiroyuki; Ito, Kyoko; Takeuchi, Yasuo; Nomura, Yoshihiro

2010-01-01

280

Kinetic studies on the yeast Phaffia rhodozyma.  

PubMed

The yeast Phaffia rhodozyma, a promising microbial producer of the carotenoid astaxanthin, was cultivated in batch and continuous processes in an agitated and aerated fermenter using an acid peat extract based culture medium. For the accelerated growth phase, the mean specific growth rate and doubling time were found to be 0.038 h-1, and 18.24 hours, respectively. The production of astaxanthin was found to be basically growth associated, the maximum concentrations of the pigment produced in batch culture and continuous cultivation being similar. PMID:7608862

Acheampong, E A; Martin, A M

1995-01-01

281

Glucose content in the liquid hydrolysate after dilute acid pretreatment is affected by the starch content in rice straw.  

PubMed

Lignocellulosic biomass, such as rice straw, is often utilized as a bioresource after being hydrolyzed using dilute acid and separated into liquid hydrolysate and acid-insoluble residue. However, the biomass component that determines the distribution between liquid hydrolysate and acid-insoluble residue has not yet been clarified. In this study, the glucose content in the liquid hydrolysate and weight of acid-insoluble residue of 13 rice cultivars were analyzed. Starch content was positively correlated with glucose content in the liquid hydrolysate, and negatively correlated with acid-insoluble residue weight. These results indicate that the glucose in the liquid hydrolysate is mainly liberated from starch rather than cellulose in the rice straw. These observations suggest that starch content is a good indicator of the glucose distribution between the liquid hydrolysate and insoluble residue. PMID:24140898

Teramura, Hiroshi; Oshima, Tomoko; Matsuda, Fumio; Sasaki, Kengo; Ogino, Chiaki; Yamasaki, Masanori; Kondo, Akihiko

2013-12-01

282

Wood impregnation of yeast lees for winemaking.  

PubMed

This study develops a new method to produce more complex wines by means of an indirect diffusion of wood aromas from yeast cell-walls. An exogenous lyophilized biomass was macerated with an ethanol wood extract solution and subsequently dried. Different times were used for the adsorption of polyphenols and volatile compounds to the yeast cell-walls. The analysis of polyphenols and volatile compounds (by HPLC/DAD and GC-MS, respectively) demonstrate that the adsorption/diffusion of these compounds from the wood to the yeast takes place. Red wines were also aged with Saccharomyces cerevisiae lees that had been impregnated with wood aromas and subsequently dried. Four different types of wood were used: chestnut, cherry, acacia and oak. Large differences were observed between the woods studied with regards to their volatile and polyphenolic profiles. Sensory evaluations confirmed large differences even with short-term contact between the wines and the lees, showing that the method could be of interest for red wine making. In addition, the results demonstrate the potential of using woods other than oak in cooperage. PMID:25308662

Palomero, Felipe; Bertani, Paolo; Fernández de Simón, Brígida; Cadahía, Estrella; Benito, Santiago; Morata, Antonio; Suárez-Lepe, José A

2015-03-15

283

Fish meals, fish components, and fish protein hydrolysates as potential ingredients in pet foods.  

PubMed

An experiment to determine the chemical composition and protein quality of 13 fish substrates (pollock by-products, n = 5; fish protein hydrolysates, n = 5; and fish meals, n = 3) was conducted. Two of these substrates, salmon protein hydrolysate (SPH) and salmon meal with crushed bones (SMB), were used to determine their palatability as components of dog diets. Pollock by-products differed in concentrations of CP, crude fat, and total AA by 71, 79, and 71%, respectively, and GE by 4.1 kcal/g. Fish protein hydrolysates and fish meals were less variable (approximately 18, 14, and 17%, and 1.4 kcal/g, respectively). Biogenic amine concentrations were much higher in fish protein hydrolysates as compared with pollock by-products and fish meals. Pollock liver and viscera had the highest total fatty acid concentrations; however, red salmon hydrolysate and SMB had the highest total PUFA concentrations (49.63 and 48.60 mg/g, respectively). Salmon protein hydrolysate had the highest protein solubility in 0.2% KOH. Based on calculations using immobilized digestive enzyme assay values, lysine digestibility of fish meal substrates was comparable to in vivo cecectomized rooster assay values and averaged approximately 90.3%. Also, pollock milt, pollock viscera, red salmon hydrolysate, and sole hydrolysate had comparable values as assessed by immobilized digestive enzyme assay and rooster assays. A chick protein efficiency ratio (PER) assay compared SMB and SPH to a whole egg meal control and showed that SMB had high protein quality (PER = 3.5), whereas SPH had poor protein quality (PER value less than 1.5). However, using whole egg meal as the reference protein, both fish substrates were found to be good protein sources with an essential AA index of 1.0 and 0.9 for SMB and SPH, respectively. In the dog palatability experiments, a chicken-based control diet and 2 diets containing 10% of either SPH or SMB were tested. Dogs consumed more of the SPH diet compared with the control, and similar amounts of the SMB and control diets. The intake ratios for each were 0.73 and 0.52, respectively. Salmon protein hydrolysate was especially palatable to dogs. These data suggest that chemical composition and nutritional quality of fish substrates differ greatly and are affected by the specific part of the fish used to prepare fish meals and fish protein hydrolysates. PMID:16971577

Folador, J F; Karr-Lilienthal, L K; Parsons, C M; Bauer, L L; Utterback, P L; Schasteen, C S; Bechtel, P J; Fahey, G C

2006-10-01

284

Antioxidant and Free Radical-Scavenging Activities of Goby (Zosterisessor ophiocephalus) Muscle Protein Hydrolysates Obtained by Enzymatic Treatment  

Microsoft Academic Search

Antioxidant activities of protein hydrolysates prepared from goby muscle by treatment with various bacterial alkaline proteases from Bacillus mojavensis A21, Bacillus subtilis A1, Bacillus pumilus A26, and Bacillus licheniformis NH1 and Alcalase were investigated. All hydrolysates showed different degrees of hydrolysis. The antioxidant activities of protein hydrolysates at different concentrations were evaluated using various in vitro antioxidant assays, including 1,1-diphenyl-2-picrylhydrazyl

Rim Nasri; Ali Bougatef; Hayet Ben Khaled; Naima Nedjar-Arroume; Maha Karra Chaâbouni; Pascal Dhulster; Moncef Nasri

2012-01-01

285

Kinetics of the inhibition of renin and angiotensin I-converting enzyme by flaxseed protein hydrolysate fractions  

Microsoft Academic Search

Enzymatic hydrolysates from flaxseed protein were investigated for in vitro inhibition of angiotensin I-converting enzyme (ACE) and renin activities. Pepsin, ficin, trypsin, papain, thermolysin, pancreatin and Alcalase were used to hydrolyze flaxseed proteins followed by fractionation using ultrafiltration to isolate low-molecular-weight peptides, and separation of the Alcalase hydrolysate into cationic peptide fractions. Using N-(3-[2-furyl]acryloyl)-phenylalanylglycylglycine as substrate, the protein hydrolysates showed

Chibuike C. Udenigwe; Yin-Shiou Lin; Wen-Chi Hou; Rotimi E. Aluko

2009-01-01

286

Chicken collagen hydrolysate protects rats from hypertension and cardiovascular damage.  

PubMed

We previously reported that chicken collagen hydrolysate (CCH) has strong angiotensin I converting enzyme (ACE) inhibitory activity and antihypertensive effects on spontaneously hypertensive rats. Here, we investigated the chronic therapy effects of CCH on blood pressure and vascular relaxation in a cardiovascular damage model of Wistar-Kyoto rats induced by N-nitro-l-arginine methyl ester (L-NAME). Following co-treatment with CCH for 4 weeks, the increment of systolic blood pressure was suppressed significantly. At 8 weeks, the vasorelaxation of thoracic aorta increased significantly, and cardiovascular damage was ameliorated. The concentration of soluble intercellular adhesion molecule-1 (ICAM-1) in blood was reduced significantly by long-term administration of CCH, whereas the nitric oxide concentration was increased significantly at 1 hour post-treatment. The results suggest that beneficial effects of CCH result from antihypertensive function, but also from inhibition of cardiovascular damage to the endothelial cells via its ACE inhibitory activity and regulation of nitric oxide and ICAM-1, which suggests that CCH may be useful as a medicinal food for patients with cardiovascular disease. PMID:20170381

Zhang, Youzuo; Kouguchi, Tomomi; Shimizu, Muneshige; Ohmori, Takashi; Takahata, Yoshihisa; Morimatsu, Fumiki

2010-04-01

287

Production of food yeast from starchy substrates  

Microsoft Academic Search

Fifteen yeast strains were selected for the production of food yeast from starchy substrates. From comparison with the amylolytic yeasts, a strain of Schwanniomyces castellii was selected and its characteristics are described.

A. Touzi; J. P. Prebois; G. Moulin; F. Deschamps; P. Galzy

1982-01-01

288

21 CFR 172.896 - Dried yeasts.  

...FOOD FOR HUMAN CONSUMPTION Multipurpose Additives § 172.896 Dried yeasts. Dried yeast (Saccharomyces cerevisiae and Saccharomyces fragilis ) and dried torula yeast (Candida utilis ) may be safely used in food provided the...

2014-04-01

289

The potential of bacteria isolated from ruminal contents of seaweed-eating North Ronaldsay sheep to hydrolyse seaweed components and produce methane by anaerobic digestion in vitro  

PubMed Central

The production of methane biofuel from seaweeds is limited by the hydrolysis of polysaccharides. The rumen microbiota of seaweed-eating North Ronaldsay sheep was studied for polysaccharidic bacterial isolates degrading brown-seaweed polysaccharides. Only nine isolates out of 65 utilized > 90% of the polysaccharide they were isolated on. The nine isolates (eight Prevotella spp. and one Clostridium butyricum) utilized whole Laminaria hyperborea extract and a range of seaweed polysaccharides, including alginate (seven out of nine isolates), laminarin and carboxymethylcellulose (eight out of nine isolates); while two out of nine isolates additionally hydrolysed fucoidan to some extent. Crude enzyme extracts from three of the isolates studied further had diverse glycosidases and polysaccharidase activities; particularly against laminarin and alginate (two isolates were shown to have alginate lyase activity) and notably fucoidan and carageenan (one isolate). In serial culture rumen microbiota hydrolysed a range of seaweed polysaccharides (fucoidan to a notably lesser degree) and homogenates of L. hyperborea, mixed Fucus spp. and Ascophyllum nodosum to produce methane and acetate. The rumen microbiota and isolates represent potential adjunct organisms or enzymes which may improve hydrolysis of seaweed components and thus improve the efficiency of seaweed anaerobic digestion for methane biofuel production. PMID:23170956

Williams, Allan G; Withers, Susan; Sutherland, Alastair D

2013-01-01

290

Biostimulant action of a plant-derived protein hydrolysate produced through enzymatic hydrolysis.  

PubMed

The aim of this study was to evaluate the biostimulant action (hormone like activity, nitrogen uptake, and growth stimulation) of a plant-derived protein hydrolysate by means of two laboratory bioassays: a corn (Zea mays L.) coleoptile elongation rate test (Experiment 1), a rooting test on tomato cuttings (Experiment 2); and two greenhouse experiments: a dwarf pea (Pisum sativum L.) growth test (Experiment 3), and a tomato (Solanum lycopersicum L.) nitrogen uptake trial (Experiment 4). Protein hydrolysate treatments of corn caused an increase in coleoptile elongation rate when compared to the control, in a dose-dependent fashion, with no significant differences between the concentrations 0.75, 1.5, and 3.0 ml/L, and inodole-3-acetic acid treatment. The auxin-like effect of the protein hydrolysate on corn has been also observed in the rooting experiment of tomato cuttings. The shoot, root dry weight, root length, and root area were significantly higher by 21, 35, 24, and 26%, respectively, in tomato treated plants with the protein hydrolysate at 6 ml/L than untreated plants. In Experiment 3, the application of the protein hydrolysate at all doses (0.375, 0.75, 1.5, and 3.0 ml/L) significantly increased the shoot length of the gibberellin-deficient dwarf pea plants by an average value of 33% in comparison with the control treatment. Increasing the concentration of the protein hydrolysate from 0 to 10 ml/L increased the total dry biomass, SPAD index, and leaf nitrogen content by 20.5, 15, and 21.5%, respectively. Thus the application of plant-derived protein hydrolysate containing amino acids and small peptides elicited a hormone-like activity, enhanced nitrogen uptake and consequently crop performances. PMID:25250039

Colla, Giuseppe; Rouphael, Youssef; Canaguier, Renaud; Svecova, Eva; Cardarelli, Mariateresa

2014-01-01

291

[Preparation and nutritional characteristics of a hydrolysate from pepitona (Arca zebra)].  

PubMed

Two soluble products resulting from the hydrolysis of pepitona (Arca zebra) were prepared as flour. Papain at its optimum hydrolysis conditions, previously established, was the enzyme used (40 degrees C for two hours at a pH of 7 in the proportion of 0.3% weight/enzyme/100 g meat). The hydrolysate obtained was then subjected to two different dehydration techniques: drum drying at 121 degrees C and 18 seconds retention, and spray drying at 101 degrees C and 40 psi pressure. The products were then stored for a five-month period at a temperature of 25 degrees C +/- 2 degrees C, time during which chemical determinations were performed in both hydrolysates. Findings showed that the time of storage does exert a significant effect of deterioration on the products. The greater and more significant quality losses occur during the first two months. The dehydration techniques used also affect significantly the soluble nitrogen content, and non-protein nitrogen and soluble solids content, as well as color of pepitona hydrolysates. Spray-drying dehydration technique does not have a significant deteriorating effect. Biological studies undertaken demonstrated that the quality of both hydrolysates is satisfactory from the nutritional and amino acid composition points of view. A protein efficiency ratio (PER) of 2.27 and 2.29 was determined for the hydrolysate dehydrated by drum drier and for the dehydrated by spray drier, respectively. With regard to amino acid composition, both had satisfactory levels of essential amino acids, with a lysine content of 6.9 g/100 g protein for the hydrolysate dehydrated by drum drying, and 8.6 g/100 g protein for the other hydrolysate dehydrated by spray drying. PMID:3842922

Arbej, J; Luna, G

1985-12-01

292

Production, Characterization, and Properties of Sophorolipids from the Yeast Candida bombicola using a Low-cost Fermentative Medium  

Microsoft Academic Search

The yeast Candida bombicola produces biosurfactant with properties akin to those of sophorolipid (SL) group of compounds. In the present work, the yeast\\u000a was shown to produce 63.7 g l?1 SL when grown on a cheap fermentative medium containing sugarcane molasses, yeast extract, urea, and soybean oil. The partially\\u000a purified SL was characterized and confirmed by Fourier-transform infrared (FT-IR) spectroscopy, 1H

Achlesh Daverey; Kannan Pakshirajan

2009-01-01

293

Housefly larvae hydrolysate: orthogonal optimization of hydrolysis, antioxidant activity, amino acid composition and functional properties  

PubMed Central

Background Antioxidant, one of the most important food additives, is widely used in food industry. At present, antioxidant is mostly produced by chemical synthesis, which would accumulate to be pathogenic. Therefore, a great interest has been developed to identify and use natural antioxidants. It was showed that there are a lot of antioxidative peptides in protein hydrolysates, possessing strong capacity of inhibiting peroxidation of macro-biomolecular and scavenging free redicals in vivo. Enzymatic hydrolysis used for preparation of antioxidative peptides is a new hot-spot in the field of natural antioxidants. It reacts under mild conditions, with accurate site-specific degradation, good repeatability and few damages to biological activity of protein. Substrates for enzymatic hydrolysis are usually plants and aqua-animals. Insects are also gaining attention because of their rich protein and resource. Antioxidative peptides are potential to be exploited as new natural antioxidant and functional food. There is a huge potential market in medical and cosmetic field as well. Result Protein hydrolysate with antioxidant activity was prepared from housefly larvae, by a two-step hydrolysis. Through orthogonal optimization of the hydrolysis conditions, the degree of hydrolysis was determined to be approximately 60%. Fractionated hydrolysate at 25?mg/mL, 2.5?mg/mL and 1?mg/mL exhibited approximately 50%, 60% and 50% of scavenging capacity on superoxide radicals, 1, 1-Diphenyl-2-picrylhydrazyl radicals and hydroxyl radicals, respectively. Hydrolysate did not exhibit substantial ion chelation. Using a linoneic peroxidation system, the inhibition activity of hydrolysate at 20?mg/mL was close to that of 20??g/mL tertiary butylhydroquinone, suggesting a potential application of hydrolysate in the oil industry as an efficient antioxidant. The lyophilized hydrolysate presented almost 100% solubility at pH 3-pH 9, and maintained nearly 100% activity at pH 5-pH 8 at 0°C- 4°C and room temperature during the first 6?months of storage. Essential amino acids in the hydrolysate accounted for 43% of the total amino acids. Conclusions The results suggesting that hydrolysate could be added to food oils as an efficient antioxidant. It might be useful for food additives, diet nutrients and pharmaceutical agents. PMID:23683361

2013-01-01

294

New and emerging yeast pathogens.  

PubMed Central

The most common yeast species that act as agents of human disease are Candida albicans, Candida tropicalis, Candida glabrata, Candida parapsilosis, and Cryptococcus neoformans. The incidence of infections by other yeasts has increased during the past decade. The most evident emerging pathogens are Malassezia furfur, Trichosporon beigelii, Rhodotorula species, Hansenula anomala, Candida lusitaniae, and Candida krusei. Organisms once considered environmental contaminants or only industrially important, such as Candida utilis and Candida lipolytica, have now been implicated as agents of fungemia, onychomycosis, and systemic disease. The unusual yeasts primarily infect immunocompromised patients, newborns, and the elderly. The role of central venous catheter removal and antifungal therapy in patient management is controversial. The antibiograms of the unusual yeasts range from resistant to the most recent azoles and amphotericin B to highly susceptible to all antifungal agents. Current routine methods for yeast identification may be insufficient to identify the unusual yeasts within 2 days after isolation. The recognition of unusual yeasts as agents of sometimes life-threatening infection and their unpredictable antifungal susceptibilities increase the burden on the clinical mycology laboratory to pursue complete species identification and MIC determinations. Given the current and evolving medical practices for management of seriously ill patients, further evaluations of the clinically important data about these yeasts are needed. PMID:8665465

Hazen, K C

1995-01-01

295

Amino acid composition and antioxidant activities of hydrolysates and peptide fractions from porcine collagen.  

PubMed

The amino acid composition and antioxidant activities of different hydrolysates from porcine collagen were analyzed. The gelatin was hydrolyzed for antioxidative peptides with various proteases, namely papain, protease from bovine pancreas, protease from Streptomyces, and cocktail mixture of protease from bovine pancreas and protease from Streptomyces. The hydrolysates were assessed using methods of DPPH radical-scavenging ability, metal-chelating ability and lipid peroxidation inhibition activity. It was found that the collagen hydrolysates by different protease treatments had different amino acid compositions and antioxidant properties. However, the contents of Hyp and Pro were improved and the content of Gly was decreased in each collagen hydrolysate compared with collagen. The hydrolysate prepared with the cocktail mixture of proteases, which exhibited the highest antioxidant activity, was separated into 6 fractions by gel filtration chromatography. Fraction 2 was further separated by ion exchange chromatography. Fraction 2b with abundant basic amino acids and Fraction 2d which was slightly acidic fractions had higher radical-scavenging and metal-chelating activities, and both Fraction 2b and 2d contained more hydrophobic amino acids. The results confirmed that the antioxidative peptides were rich in Hyp, Pro and Gly, which accounted for half of amino acid composition. This article added further support to the preparation of natural antioxidative peptides from porcine skin collagen. PMID:23064526

Ao, Jing; Li, Bo

2012-10-01

296

Isolation and Characterization of a Nitrile-Hydrolysing Bacterium Isoptericola variabilis RGT01.  

PubMed

A nitrile-hydrolysing bacterium, identified as Isoptericola variabilis RGT01, was isolated from industrial effluent through enrichment culture technique using acrylonitrile as the carbon source. Whole cells of this microorganism exhibited a broad range of nitrile-hydrolysing activity as they hydrolysed five aliphatic nitriles (acetonitrile, acrylonitrile, propionitrile, butyronitrile and valeronitrile), two aromatic nitriles (benzonitrile and m-Tolunitrile) and two arylacetonitriles (4-Methoxyphenyl acetonitrile and phenoxyacetonitrile). The nitrile-hydrolysing activity was inducible in nature and acetonitrile proved to be the most efficient inducer. Minimal salt medium supplemented with 50 mM acetonitrile, an incubation temperature of 30 °C with 2 % v/v inoculum, at 200 rpm and incubation of 48 h were found to be the optimal conditions for maximum production (2.64 ± 0.12 U/mg) of nitrile-hydrolysing activity. This activity was stable at 30 °C as it retained around 86 % activity after 4 h at this temperature, but was thermolabile with a half-life of 120 min and 45 min at 40 °C and 50 °C respectively. PMID:25320428

Kaur, Gurdeep; Soni, Pankaj; Tewari, Rupinder; Sharma, Rohit

2014-06-01

297

Interaction of Ddc1 and RPA with single-stranded/double-stranded DNA junctions in yeast whole cell extracts: Proteolytic degradation of the large subunit of replication protein A in ddc1? strains.  

PubMed

To characterize proteins that interact with single-stranded/double-stranded (ss/ds) DNA junctions in whole cell free extracts of Saccharomyces cerevisiae, we used [(32)P]-labeled photoreactive partial DNA duplexes containing a 3'-ss/ds-junction (3'-junction) or a 5'-ss/ds-junction (5'-junction). Identification of labeled proteins was achieved by MALDI-TOF mass spectrometry peptide mass fingerprinting and genetic analysis. In wild-type extract, one of the components of the Ddc1-Rad17-Mec3 complex, Ddc1, was found to be preferentially photocrosslinked at a 3'-junction. On the other hand, RPAp70, the large subunit of the replication protein A (RPA), was the predominant crosslinking product at a 5'-junction. Interestingly, ddc1? extracts did not display photocrosslinking of RPAp70 at a 5'-junction. The results show that RPAp70 crosslinked to DNA with a 5'-junction is subject to limited proteolysis in ddc1? extracts, whereas it is stable in WT, rad17?, mec3? and mec1? extracts. The degradation of the RPAp70-DNA adduct in ddc1? extract is strongly reduced in the presence of the proteasome inhibitor MG 132. We also addressed the question of the stability of free RPA, using anti-RPA antibodies. The results show that RPAp70 is also subject to proteolysis without photocrosslinking to DNA upon incubation in ddc1? extract. The data point to a novel property of Ddc1, modulating the turnover of DNA binding proteins such as RPAp70 by the proteasome. PMID:25089887

Sukhanova, Maria V; D'Herin, Claudine; Boiteux, Serge; Lavrik, Olga I

2014-10-01

298

Simple improvement in freeze-tolerance of bakers' yeast with poly-gamma-glutamate.  

PubMed

We examined the effect of poly-gamma-glutamate (PGA) on the freeze-tolerance of four types of commercial bakers' yeast (freeze-tolerant, osmotic-tolerant, low-temperature-sensitive, and ordinary bakers' yeasts). The survival ratio of ordinary bakers' yeast cells frozen at -30 degrees C for 3 d in a medium (0.5% yeast extract, 0.5% peptone, and 2% glucose: YPD medium) was improved by adding more than 1% PGA to the medium; the survival ratio increased from about 10% to more than 70%. All PGA preparations, which differed in average molecular mass (50, 2,000, 4,000, 6,000, 8,000, and 10,000 kDa), showed a similar cryoprotecive effect on the cells. Similar results were also obtained with other types of bakers' yeast, sake yeast and beer yeast. When the four types of bakers' yeast cell were frozen at -30 degrees C for 3 d in dough supplemented with more than 1% PGA, the cells (after freezing and thawing) showed higher leavening ability than those frozen in dough without PGA, irrespective of the molecular mass of PGA. Thus, PGA appears to protect bakers' yeast from lethal freeze injury, leading to a high leavening ability after freezing and thawing. PGA did not decrease the original leavening ability of the bakers' yeast, and was not decomposed by the yeast cells. PGA suppressed the decrease in leavening ability during a prolonged fermentation time, probably because PGA adsorbed inhibitory metabolites accumulated in the dough. PGA could prove useful for improving the freeze-tolerance of bakers' yeast by its addition to dough. PMID:17046536

Yokoigawa, Kumio; Sato, Machiko; Soda, Kenji

2006-09-01

299

Object extraction Object extraction  

E-print Network

Object extraction #12;Object extraction · Extracting topographic objects from images · the main goal of aerial photogrammetry · object extraction consists of two steps · image interpretation extraction · Extracting topographic objects from images · identify all objects of a certain class · measure

Giger, Christine

300

A combined chemical and enzymatic method to determine quantitatively the polysaccharide components in the cell wall of yeasts.  

PubMed

A reliable method to determine cell wall polysaccharides composition in yeast is presented, which combines acid and enzymatic hydrolysis. Sulphuric acid treatment is used to determine mannans, whereas specific hydrolytic enzymes are employed in a two sequential steps to quantify chitin and the proportion of ?-(1,3) and ?-(1,6)-glucan in the total ?-glucan of the cell wall. In the first step, chitin and ?-(1,3)-glucan were hydrolysed into their corresponding monomers N-acetylglucosamine and glucose, respectively, by the combined action of a chitinase from Streptomyces griseus and a pure preparation of endo/exo-?-(1,3)-glucanase from Trichoderma species. This step was followed by addition of recombinant endo-?-(1,6)-glucanase from Trichoderma harzianum with ?-glucosidase from Aspergillus niger to hydrolyse the remaining ?-glucan. This latter component corresponded to a highly branched ?-(1,6)-glucan that contained about 75-80% of linear ?-(1,6)-glucose linked units as deduced from periodate oxidation. We validated this novel method by showing that the content of ?-(1,3), ?-(1,6)-glucan or chitin was dramatically decreased in yeast mutants defective in the biosynthesis of these cell wall components. Moreover, we found that heat shock at 42 °C in Saccharomyces cerevisiae and treatment of this yeast species and Candida albicans with the antifungal drug caspofungin resulted in 2- to 3-fold increase of chitin and in a reduction of ?-(1,3)-glucan accompanied by an increase of ?-(1,6)-glucan, whereas ethanol stress had apparently no effect on yeast cell wall composition. PMID:25041403

Schiavone, Marion; Vax, Amélie; Formosa, Cécile; Martin-Yken, Hélène; Dague, Etienne; François, Jean M

2014-09-01

301

Brewer's yeast and sugarcane yeast as protein sources for dogs.  

PubMed

Brewer's yeast (BY), autolysed sugarcane yeast (ASCY) and integral sugar cane yeast (ISCY) were studied in two experiments as ingredients for dog diets. In the first experiment, 28 dogs were randomly assigned to four diets; one reference diet and three test diets containing 15% of BY, ASCY or ISCY and 85% of the reference diet (as-fed basis). The digestibilities of the yeasts were calculated by the substitution method. In the second experiment, 35 dogs were randomized to five diets with similar chemical composition but different levels of sugarcane yeast inclusion (0%, 7.5% ASCY, 15% ASCY, 7.5% ISCY and 15% ISCY). In both experiments, the coefficient of total tract apparent digestibility (CTTAD) of nutrients was determined through total collection of faeces. During experiment, two additional analyses of food palatability, nitrogen balance and urea postprandial responses were performed. The data were submitted to analysis of variance, and the means were compared by orthogonal or polynomial contrasts or Tukey's test (p < 0.05). In experiment 1, CTTAD of protein was lower for both sugarcane yeasts than for BY (p = 0.012), as was metabolizable energy content (p = 0.025). In experiment 2, a linear reduction in energy digestibility with ASCY inclusion (p = 0.05) was verified. Furthermore, faecal score and DM content were reduced with ISCY inclusion (p < 0.003). No effect of yeast inclusion on nitrogen balance or postprandial urea response was found. Also, the inclusion of 7.5% of ASCY or ISCY increased diet palatability (p < 0.01). Yeasts present adequate digestibility by dogs, but its effect on faecal formation needs to be considered. No clear advantage for the use of ASCY over ISCY was found. In conclusion, we find that sugarcane yeast is suitable for inclusion in dog food and can enhance the overall palatability of the diet. PMID:24304448

Martins, M S; Sakomura, N K; Souza, D F; Filho, F O R; Gomes, M O S; Vasconcellos, R S; Carciofi, A C

2014-10-01

302

Microbial production of 2,3 butanediol from seaweed hydrolysate using metabolically engineered Escherichia coli.  

PubMed

A variety of biofuel and biorefinery products have been produced from engineered Escherichia coli till date. Most of these products had been derived from simple sugars in its pure form, rather than deriving it from alternative, renewable and carbon neutral sources, such as marine alga biomass. Engineering E. coli to use algal hydrolysate can make these an attractive carbon source for the industrial production of value added fuels and chemicals. This work reports the engineering of E. coli by a combination of gene deletion and synthetic pathway incorporation, for the efficient utilization of algal hydrolysate to produce BA (2,3 butanediol+acetoin) under microaerobic condition. Engineered strain produced ~19 g/L of total BA from algal hydrolysate in defined M9 salt media at a yield of 0.43 g/g. PMID:23567699

Mazumdar, Suman; Lee, Jinwon; Oh, Min-Kyu

2013-05-01

303

Acid-generated soy protein hydrolysates and their interfacial behavior on model surfaces.  

PubMed

The present work attempts to provide data to warrant the consideration of soy proteins (SP) as potentially useful biomolecules for practical chemical and surface applications. Despite their sundry properties, SP use has been limited by their high molecular weight. In response to this limitation, we analyze acid hydrolysates of soy proteins (0.1 N HCl, 70 °C) for surface modification. Techniques typical in protein (SDS-PAGE) as well as colloidal (charge demand and electrophoretic mobility) analyses were used to follow the effects of molecular changes that occur upon hydrolysis. Adsorption experiments on hydrophobic (polypropylene) and mineral (aluminum oxide) surfaces were subsequently carried out to further interrogate the surface activity resultant from soy hydrolysis. It was found that during adsorption the hydrolysates tended to form less surface aggregates and adsorbed at faster rates compared with unmodified SP. Overall, the benefits derived from the application of SP hydrolysates are highlighted. PMID:25314296

Arboleda, Julio C; Rojas, Orlando J; Lucia, Lucian A

2014-11-10

304

Utilization of meat industry by products: protein hydrolysate from sheep visceral mass.  

PubMed

Protein hydrolysate was prepared from pre-treated sheep visceral mass (including stomach, large and small intestines) by enzymatic treatment at 43+/-1 degrees C (at the in situ pH 7.1+/-0.2 of the visceral mass) using fungal protease. The enzyme readily solubilized the proteins of the visceral mass as indicated by the degree of hydrolysis (34%) and nitrogen recovery (>64%). Hydrolysis with an enzyme level of 1% (w/w of total solids) at 43+/-1 degrees C with a pH around 7.0 for 45 min was found to be the optimum condition. The yield of protein hydrolysate was about 6% (w/w). The amino acid composition of the protein hydrolysate that was very hygroscopic, was comparable to that of casein. PMID:16457999

Bhaskar, N; Modi, V K; Govindaraju, K; Radha, C; Lalitha, R G

2007-01-01

305

Innovative approaches for converting a wood hydrolysate to high-quality barrier coatings.  

PubMed

An advanced approach for the efficient and controllable production of softwood hydrolysate-based coatings with excellent oxygen-barrier performance is presented. An innovative conversion of the spray-drying technique into a coating applicator process allowed for a fast and efficient coating process requiring solely aqueous solutions of softwood hydrolysate, even without additives. Compared to analogous coatings prepared by manual application, the spray-drying produced coatings were more homogeneous and smooth, and they adhered more strongly to the substrate. The addition of glyoxal to the aqueous softwood hydrolysate solutions prior to coating formation allowed for hemicellulose cross-linking, which improved both the mechanical integrity and the oxygen-barrier performance of the coatings. A real-time scanning electron microscopy imaging assessment of the tensile deformation of the coatings allowed for a deeper understanding of the ability of the coating layer itself to withstand stress as well as the coating-to-substrate adhesion. PMID:23915190

Ryberg, Yingzhi Zhu; Edlund, Ulrica; Albertsson, Ann-Christine

2013-08-28

306

Study on the free radical scavenging activity of sea cucumber (Paracaudina chinens var.) gelatin hydrolysate  

NASA Astrophysics Data System (ADS)

Gelatin from the sea cucumber (Paracaudina chinens var.) was hydrolyzed by bromelain and the hydrolysate was found to have a high free radical scavenging activity. The hydrolysate was fractionated through an ultrafiltration membrane with 5 kDa molecular weight cutoff (MWCO). The portion (less than 5 kDa) was further separated by Sephadex G-25. The active peak was collected and assayed for free radical scavenging activity. The scavenging rates for superoxide anion radicals (O2·-) and hydroxyl radicals (·OH) of the fraction with the highest activity were 29.02% and 75.41%, respectively. A rabbit liver mitochondrial free radical damage model was adopted to study the free radical scavenging activity of the fraction. The results showed that the sea cucumber gelatin hydrolysate can prevent the damage of rabbit liver and mitochondria.

Zeng, Mingyong; Xiao, Feng; Zhao, Yuanhui; Liu, Zunying; Li, Bafang; Dong, Shiyuan

2007-07-01

307

Immobilized yeast bioreactor systems for continuous beer fermentation  

PubMed

Two different types of immobilized yeast bioreactors were examined for continuous fermentation of high-gravity worts. One of these is a fluidized bed reactor (FBR) that employs porous glass beads for yeast immobilization. The second system is a loop reactor containing a porous silicon carbide cartridge (SCCR) for immobilizing the yeast cells. Although there was some residual fermentable sugar in the SCCR system product, nearly complete attenuation of the wort sugars was achieved in either of the systems when operated as a two-stage process. Fermentation could be completed in these systems in only half the time required for a conventional batch process. Both the systems showed similar kinetics of extract consumption, and therefore similar volumetric productivity. As compared to the batch fermentation, total fusel alcohols were lower; total esters, while variable, were generally higher. The yeast biomass production was similar to that in a conventional fermentation process. As would be expected in an accelerated fermentation system, the levels of vicinal diketones (VDKs) were higher. To remove the VDKs, the young beer was heat-treated to convert the VDK precursors and processed through a packed bed immobilized yeast bioreactor for VDK assimilation. The finished product from the FBR system was found to be quite acceptable from a flavor perspective, albeit different from the product from a conventional batch process. Significantly shortened fermentation times demonstrate the feasibility of this technology for beer production. PMID:9933520

Tata; Bower; Bromberg; Duncombe; Fehring; Lau; Ryder; Stassi

1999-01-01

308

Optical trapping and surgery of living yeast cells using a single laser.  

PubMed

We present optical trapping and surgery of living yeast cells using two operational modes of a single laser. We used a focused laser beam operating in continuous-wave mode for noninvasive optical trapping and manipulation of single yeast cell. We verified that such operational mode of the laser does not cause any destructive effect on yeast cell wall. By changing the operation of the laser to femtosecond-pulsed mode, we show that a tightly focused beam dissects the yeast cell walls via nonlinear absorption. Lastly, using the combined technique of optical microsurgery and trapping, we demonstrate intracellular organelle extraction and manipulation from a yeast cell. The technique established here will be useful as an efficient method for both surgery and manipulation of living cells using a single laser beam. PMID:19044717

Ando, Jun; Bautista, Godofredo; Smith, Nicholas; Fujita, Katsumasa; Daria, Vincent Ricardo

2008-10-01

309

Phytochemical screening of Nepeta cataria extracts and their in vitro inhibitory effects on free radicals and carbohydrate-metabolising enzymes.  

PubMed

This research was performed to investigate in vitro the biological activities of successive as well as 70% ethanol extracts of Nepeta cataria on some biochemical parameters including oxidative markers and carbohydrate-hydrolysing enzyme activities (?-amylase, ?-galactosidase and ?-glucosidase). Powdered N. cataria and its successive extracts were screened for their phytochemical constituents. Tests for tannins, carbohydrates, glycosides and flavonoids were positive in ethanolic extract, but those for steroids and terpenoids were positive in petroleum ether and chloroform extracts. Also, different extracts were chromatographically investigated. The results obtained demonstrated that different successive extracts of N. cataria exhibited an inhibitory effect on oxidative stress indices and carbohydrate-hydrolysing enzymes. It is observed that 70% ethanol, petroleum ether and chloroform extracts showed, respectively, the most potent inhibitory activities, while ethyl acetate and ethanol successive extracts appeared with moderate or low reducing activities. PMID:22103287

Naguib, Abdel Moneam Mohamed; Ebrahim, Mohamed Elsayed; Aly, Hanan Farouk; Metawaa, Hemaia Mohamed; Mahmoud, Ahlam Hosni; Mahmoud, Ebtissam A; Ebrahim, Faten Mohamed

2012-01-01

310

Characterisation of kiwifruit and asparagus enzyme extracts, and their activities toward meat proteins.  

PubMed

Two plant enzyme extracts from kiwifruit and asparagus were evaluated for their ability to hydrolyse commercially available substrates and proteins present in both beef connective tissue and topside myofibrillar extracts. The results show significant differences in protease activity depending on the assay used. Protease assays with connective tissue and meat myofibrillar extracts provide a more realistic evaluation of the potential of the enzymes for application in meat tenderization. Overall, the kiwifruit protease extract was found to be more effective at hydrolysing myofibrillar and collagen proteins than the asparagus protease extract. The two protease extracts appeared to target meat myofibrillar and collagen proteins differently, suggesting the potential of a synergistic effect of these proteases in improving the tenderness of specific cuts of meat, based on their intrinsic protein composition. PMID:23122154

Ha, Minh; Bekhit, Alaa El-Din; Carne, Alan; Hopkins, David L

2013-01-15

311

Enhanced mobility of organic thin film transistors by water absorption of collagen hydrolysate gate dielectric  

NASA Astrophysics Data System (ADS)

Collagen hydrolysate is a nature protein, which works well as the gate dielectric for organic thin film transistors (OTFTs). The pentacene OTFTs exhibit a field-effect mobility (?FE) value of 0.8 cm2V-1s-1 and an on/off ratio of 105 in vacuum. The drain current is greatly enhanced and the ?FE value increases to ca. 15.5 cm2V-1s-1 when OTFTs are exposed to air. The enhancement of ?FE is attributed to the interaction of water and OH-groups in collagen hydrolysate in air ambient.

Hsieh, Chao-Ying; Hwang, Jenn-Chang; Chang, Ting-Hao; Li, Jiun-Yi; Chen, Shih-Han; Mao, Lung-Kai; Tsai, Li-Shiuan; Chueh, Yu-Lun; Lyu, Ping-Chiang; Hsu, Shawn S. H.

2013-07-01

312

Le Lait (1980), LX, 619-634 tude compare de l'hydrolyse du lactose  

E-print Network

lactose du lactosérum déprotéiné, qui conduisent à la production d'un mélange de sucres liquides, ouvrentLe Lait (1980), LX, 619-634 �tude comparée de l'hydrolyse du lactose à l'aide des résines résine échangeuse de cations (R.E.C.) et la seconde l'hydrolyse enzymatique. Dans ce dernier cas, l'enzyme

Boyer, Edmond

313

Le Lait (1981), 61, 282-293 L'hydrolyse du lactose  

E-print Network

justifiant l'hydrolyse est l'intolérance à l'égard du lactose. Une insuffisance de la production de lactase. On a examiné ensuite les possibilités d'hydrolyse de longue durée du lactose à l'aide de petites doses d'enzyme température d'une ligne de production déterminée. #12;TABLEAU 1 Doses d'enzyme à employer pour obtenir, dans

Boyer, Edmond

314

Culture Duration Modulates Collagen Hydrolysate-Induced Tissue Remodeling in Chondrocyte-Seeded Agarose Hydrogels  

Microsoft Academic Search

Media supplementation with collagen hydrolysate was hypothesized to increase the collagen content in engineered cartilage.\\u000a By d28, hydrolysate at 0.5 mg\\/mL increased type II collagen content and 1 mg\\/mL increased mechanical properties, total collagen\\u000a content, and type II collagen content over controls. By d42, however, controls possessed the highest GAG content and compressive\\u000a Young’s modulus. Real-time PCR found that 1 mg\\/mL increased type

Kenneth W. Ng; Justin D. Saliman; Evan Y. Lin; Lauren Y. Statman; Lindsay E. Kugler; Sean B. Lo; Gerard A. Ateshian; Clark T. Hung

2007-01-01

315

Mutagenic and antimutagenic activities of aqueous and methanol extracts of Euphorbia hirta.  

PubMed

Euphorbia hirta (E. hirta) is a weed commonly found in tropical countries and has been used traditionally for asthma, bronchitis and conjunctivitis. However, one of the constituents in this plant, quercetin, was previously reported to be mutagenic. This work aimed to determine the level of quercetin in the aqueous and methanol plant extracts and to investigate the mutagenic effects of quercetin and the extracts in the Ames test utilising the mutant Salmonella typhimurium TA98 and TA100 strains. The antimutagenic activity of Euphorbia hirta aqueous and methanol extracts was also studied in Salmonella typhimurium TA98. HPLC analyses showed that quercetin and rutin, a glycosidic form of quercetin, were present in the acid-hydrolysed methanol extract and non-hydrolysed methanol extract respectively. The quercetin concentration was negligible in both non-hydrolysed and acid-hydrolysed aqueous extracts. The total phenolic contents in Euphorbia hirta were determined to be 268 and 93 mg gallic acid equivalent (GAE) per gram of aqueous and methanol extracts, respectively. Quercetin (25 microg/mL) was found to be strongly mutagenic in Salmonella typhimurium TA98 in the absence and presence of S-9 metabolic activation. However, both the aqueous and methanol extracts did not demonstrate any mutagenic properties when tested with Salmonella typhimurium TA98 and TA100 strains at concentrations up to 100 microg/mL in the absence and presence of S-9 metabolic activation. In the absence of S-9 metabolic activation, both the extracts were unable to inhibit the mutagenicity of the known mutagen, 2-nitrofluorene, in Salmonella typhimurium TA98. On the other hand, the aqueous extracts at 100 microg/mL and methanol extracts at 10 and 100 microg/mL exhibited strong antimutagenic activity against the mutagenicity of 2-aminoanthracene, a known mutagen, in the presence of S-9 metabolic activating enzymes. The results indicated that these extracts could modulate the xenobiotic metabolising enzymes in the liver at the higher concentrations. PMID:19778596

Loh, Daphne Sue Yen; Er, Hui Meng; Chen, Yu Sui

2009-12-10

316

Yeast Lipids Can Phase-separate into Micrometer-scale Membrane Domains*  

PubMed Central

The lipid raft concept proposes that biological membranes have the potential to form functional domains based on a selective interaction between sphingolipids and sterols. These domains seem to be involved in signal transduction and vesicular sorting of proteins and lipids. Although there is biochemical evidence for lipid raft-dependent protein and lipid sorting in the yeast Saccharomyces cerevisiae, direct evidence for an interaction between yeast sphingolipids and the yeast sterol ergosterol, resulting in membrane domain formation, is lacking. Here we show that model membranes formed from yeast total lipid extracts possess an inherent self-organization potential resulting in liquid-disordered-liquid-ordered phase coexistence at physiologically relevant temperature. Analyses of lipid extracts from mutants defective in sphingolipid metabolism as well as reconstitution of purified yeast lipids in model membranes of defined composition suggest that membrane domain formation depends on specific interactions between yeast sphingolipids and ergosterol. Taken together, these results provide a mechanistic explanation for lipid raft-dependent lipid and protein sorting in yeast. PMID:20647309

Klose, Christian; Ejsing, Christer S.; García-Sáez, Ana J.; Kaiser, Hermann-Josef; Sampaio, Julio L.; Surma, Michal A.; Shevchenko, Andrej; Schwille, Petra; Simons, Kai

2010-01-01

317

Vacuoles of Candida yeast as a specialized niche for Helicobacter pylori.  

PubMed

Helicobacter pylori (H. pylori) are resistant to hostile gastric environments and antibiotic therapy, reflecting the possibility that they are protected by an ecological niche, such as inside the vacuoles of human epithelial and immune cells. Candida yeast may also provide such an alternative niche, as fluorescently labeled H. pylori were observed as fast-moving and viable bacterium-like bodies inside the vacuoles of gastric, oral, vaginal and foodborne Candida yeasts. In addition, H. pylori-specific genes and proteins were detected in samples extracted from these yeasts. The H. pylori present within these yeasts produce peroxiredoxin and thiol peroxidase, providing the ability to detoxify oxygen metabolites formed in immune cells. Furthermore, these bacteria produce urease and VacA, two virulence determinants of H. pylori that influence phago-lysosome fusion and bacterial survival in macrophages. Microscopic observations of H. pylori cells in new generations of yeasts along with amplification of H. pylori-specific genes from consecutive generations indicate that new yeasts can inherit the intracellular H. pylori as part of their vacuolar content. Accordingly, it is proposed that yeast vacuoles serve as a sophisticated niche that protects H. pylori against the environmental stresses and provides essential nutrients, including ergosterol, for its growth and multiplication. This intracellular establishment inside the yeast vacuole likely occurred long ago, leading to the adaptation of H. pylori to persist in phagocytic cells. The presence of these bacteria within yeasts, including foodborne yeasts, along with the vertical transmission of yeasts from mother to neonate, provide explanations for the persistence and propagation of H. pylori in the human population. This Topic Highlight reviews and discusses recent evidence regarding the evolutionary adaptation of H. pylori to thrive in host cell vacuoles. PMID:24833856

Siavoshi, Farideh; Saniee, Parastoo

2014-05-14

318

Production of malic and succinic acids by sugar-tolerant yeast Zygosaccharomyces rouxii  

Microsoft Academic Search

Zygosaccharomyces rouxii V19 was grown in YPG medium (yeast extract, 0.5%, peptone, 1.0%, glucose, 10%). Fermented broth was purified through a series of ion-exchange columns and ODS column and the purified sample was TMS-esterified. Malic and succinic acids were identified with GC-MS analysis. The yeast was cultivated under various cultural conditions and quantitative determination of the organic acids was carried

Ok Taing; Kazuya Taing

2007-01-01

319

Properties of a pentulose-5-phosphate phosphoketolase from yeasts grown on xylose  

Microsoft Academic Search

Phosphoketolase activity from nine yeasts grown on xylose occurred with both xylulose 5-phosphate (Xu5P) and ribulose 5-phosphate (Ru5P) as substrates. With extracts from five yeasts (Candida curvata, C. famata, Lipomyces starkeyi, Rhodotorula glutinis and Pachysolen tannophilus) activity was approximately the same with either substrate; with C. boidinii, Pichia media and Yarrowia lipolytica Ru5P was the preferred substrate; and with Rhodosporidium

Colin Ratledge; Jane E. Holdsworth

1985-01-01

320

Yeast Metabolism Lab Mrs. Zimmerman  

E-print Network

Energy from sunlight #12;Respiration #12;Cellular Respiration C6H12O6 + 6 O2 6 CO2 + 6 H2O + energyYeast Metabolism Lab Mrs. Zimmerman 10/22/10 #12;Photosynthesis 6 CO2 + 6 H2O C6H12O6 + 6 O2 Oxygen Glucose Carbon Dioxide Water Energy #12;Yeast · Unicellular · Eukaryotic (like us) · Kingdom Fungi

Rose, Michael R.

321

A new pullulan-producing yeast and medium optimization for its exopolysaccharide production  

NASA Astrophysics Data System (ADS)

Yeast strain Y68 producing high level of pullulan was isolated from the phyton collected in Toulouse, France. This strain was identified to be Rhodotorula bacarum by BIOLOG analysis. This is the first report that pullulan was produced by Rhodotorula bacarum. The optimal medium (g L-1) for pullulan production by this strain was 80 glucose, 20 soybean cake hydrolysate, 5 K2HPO4, 1 NaCl, 0.2 MgSO4·7H2O, 0.6 (NH4)2SO4, pH 7.0. Under this condition, 54 gL-1 pullulan was produced within 60 h at 30°C. Pullulan is a better starting material for producing marine prodrugs.

Shuangzhi, Zhao; Zhenming, Chi

2003-04-01

322

Study of amyloids using yeast  

PubMed Central

Summary Saccharomyces cerevisiae has been a useful model organism in such fields as the cell cycle, regulation of transcription, protein trafficking and cell biology, primarily because of its ease of genetic manipulation. This is no less so in the area of amyloid studies. The endogenous yeast amyloids described to date include prions, infectious proteins (Table 1), and some cell wall proteins (1). and amyloids of humans and a fungal prion have also been studied using the yeast system. Accordingly, the emphasis of this chapter will be on genetic, biochemical, cell biological and physical methods particularly useful in the study of yeast prions and other amyloids studied in yeast. We limit our description of these methods to those aspects which have been most useful in studying yeast prions, citing more detailed expositions in the literature. Volumes on yeast genetics methods (2–4), and on amyloids and prions (5, 6) are useful, and Masison has edited a volume of Methods on “Identification, analysis and characterization of fungal prions” which covers some of this territory (7). We also outline some useful physical methods, pointing the reader to more extensive and authoratative descriptions. PMID:22528100

Wickner, Reed B.; Kryndushkin, Dmitry; Shewmaker, Frank; McGlinchey, Ryan; Edskes, Herman K.

2012-01-01

323

Yeast models for amyloid disease.  

PubMed

Saccharomyces cerevisiae (baker's yeast) is a well-established eukaryotic model organism, which has significantly contributed to our understanding of mechanisms that drive numerous core cellular processes in higher eukaryotes. Moreover, this has led to a greater understanding of the underlying pathobiology associated with disease in humans. This tractable model offers an abundance of analytical capabilities, including a vast array of global genetics and molecular resources that allow genome-wide screening to be carried out relatively simply and cheaply. A prime example of the versatility and potential for applying yeast technologies to explore a mammalian disease is in the development of yeast models for amyloid diseases such as Alzheimer's, Parkinson's and Huntington's. The present chapter provides a broad overview of high profile human neurodegenerative diseases that have been modelled in yeast. We focus on some of the most recent findings that have been developed through genetic and drug screening studies using yeast genomic resources. Although this relatively simple unicellular eukaryote seems far removed from relatively complex multicellular organisms such as mammals, the conserved mechanisms for how amyloid exhibits toxicity clearly underscore the value of carrying out such studies in yeast. PMID:25131588

Panaretou, Barry; Jones, Gary W

2014-01-01

324

Yeasts preservation: alternatives for lyophilisation.  

PubMed

The aim of the study was to compare the effect of two low-cost, low technology traditional methods for drying starter cultures with standard lyophilisation. Lyophilised yeast cultures and yeast cultures preserved in dry rice cakes and dry plant fibre strands were examined for viable cell counts during 6 months storage at 4 and 25 °C. None of the yeast cultures showed a significant loss in viable cell count during 6 months of storage at 4 °C upon lyophilisation and preservation in dry rice cakes. During storage at 25 °C in the dark, yeast cultures preserved in dry rice cakes, and lyophilised cultures of Saccharomyces cerevisiae and Issatchenkia orientalis showed no significant loss of viable cells up to 4 months of storage. Yeast cultures preserved in dry plant fibre strands had the greatest loss of viable count during the 6 months of storage at 25 °C. Preservation of yeasts cultures in dry rice cakes provided better survival during storage at 4 °C than lyophilisation. The current study demonstrated that traditional methods can be useful and effective for starter culture preservation in small-scale, low-tech applications. PMID:22806747

Nyanga, Loveness K; Nout, Martinus J R; Smid, Eddy J; Boekhout, Teun; Zwietering, Marcel H

2012-11-01

325

The secondary structure of heated whey protein and its hydrolysates antigenicity.  

PubMed

Fourier transform infrared spectroscopy (FTIR) and circular dichroism (CD) were used to investigate the conformational changes of heated whey protein (WP) and the corresponding changes in the hydrolysates immunoreactivity were determined by competitive enzyme-linked immunosorbent assay (ELISA). Results showed that the contents of alpha- helix and beta-sheet of WP did not decrease much under mild heating conditions and the antigenicity was relatively high; when the heating intensity increased (70 degrees for 25 min or 75 degrees C for 20 min), the content of alpha- helix and beta-sheet decreased to the minimum, so was the antigenicity; However, when the WP was heated at even higher temperature and for a longer time, the beta-sheet associated with protein aggregation begun to increase and the antigenicity increased correspondingly. It was concluded that the conformations of heated WP and the antigenicity of its hydrolysates are related and the optimum structure for decreasing the hydrolysates antigeniity is the least content of alpha-helix and beta-sheet. Establishing the relationship between the WP secondary structure and WP hydrolysates antigenicity is significant to supply the reference for antigenicity reduction by enzymolysis. PMID:22242516

Pang, Zhi-Hua; Zhu, Jun; Wu, Wei-Jing; Wang, Fang; Ren, Fa-Zheng; Zhang, Lu-Da; Guo, Hui-Yuan

2011-11-01

326

Protein Hydrolysates from Non-bovine and Plant Sources Replaces Tryptone in Microbiological Media  

NASA Astrophysics Data System (ADS)

Tryptone (pancreatic digest of casein) is a common ingredient in laboratory and fermentation media for growing wild-type and genetically modified microorganisms. Many of the commercially manufactured products such as human growth hormone, antibiotics, insulin, etc. are produced by recombinant strains grown on materials derived from bovine sources. With the emergence of Bovine Spongiform Encephalopathy (BSE) and the consequent increase in Food and Drug Administration (FDA) regulations, elimination of materials of bovine origin from fermentation media is of paramount importance. To achieve this objective, a number of protein hydrolysates derived from non-bovine animal and plant sources were evaluated. Tryptone in Luria-Bertani (LB) broth was replaced with an equal quantity of alternate protein hydrolysates. Four of the six hydrolysates (one animal and three from plants) were found to efficiently replace the tryptone present in LB-medium as measured by growth rate and growth yield of a recombinant Escherichia coli strain. In addition, we have determined plasmid stability, inducibility and activity of the plasmid encoded ?-galactosidase in the recombinant strain grown in the presence of various protein hydrolysates.

Ranganathan, Yamini; Patel, Shifa; Pasupuleti, Vijai K.; Meganathan, R.

327

Culture duration modulates collagen hydrolysate-induced tissue remodeling in chondrocyte-seeded agarose hydrogels.  

PubMed

Media supplementation with collagen hydrolysate was hypothesized to increase the collagen content in engineered cartilage. By d28, hydrolysate at 0.5 mg/mL increased type II collagen content and 1 mg/mL increased mechanical properties, total collagen content, and type II collagen content over controls. By d42, however, controls possessed the highest GAG content and compressive Young's modulus. Real-time PCR found that 1 mg/mL increased type II collagen gene expression in d0 constructs, but increased MMP expression with no effect on type II collagen on d28. A 10 mg/mL concentration produced the lowest tissue properties, the lowest type II collagen gene expression on d0, and the highest MMP gene expression on d28. These results indicate that the duration of culture modulates the response of chondrocytes to collagen hydrolysate in 3D culture, transforming the response from positive to negative. Therefore, collagen hydrolysate as a media supplement is not a viable long-term method to improve the collagen content of engineered cartilage tissue. PMID:17721729

Ng, Kenneth W; Saliman, Justin D; Lin, Evan Y; Statman, Lauren Y; Kugler, Lindsay E; Lo, Sean B; Ateshian, Gerard A; Hung, Clark T

2007-11-01

328

Evaluation of the hypotensive potential of bovine and porcine collagen hydrolysates.  

PubMed

Angiotensin-converting enzyme (ACE) inhibitory activity and antihypertensive activity of bovine and porcine collagen hydrolysates in spontaneously hypertensive rats (SHR) were investigated. The hydrolyzed collagens were subjected to ultrafiltration using membranes with cutoffs of 30-50 kDa (permeate P1), 5-8 kDa (permeate P2), or 1-2 kDa (permeate P3) in order to obtain products with a narrower range of molecular size. The hydrolyzed bovine and porcine collagens and their permeates showed low ACE inhibitory activity (50% inhibitory concentration [IC(50)] = 5.42-15.58 mg of protein/mL). However, after in vitro gastrointestinal digestion, a significant increase in the ACE inhibitory potency of the hydrolyzed collagens was observed (IC(50) = 0.97-4.02 mg of protein/mL). Permeates had a higher ACE inhibitory activity and hypotensive activity than non-ultrafiltered hydrolysates. The P1 permeate of bovine and porcine collagen and the P3 fraction of the porcine collagen hydrolysate exhibited the best antihypertensive activity in vivo, promoting a maximum reduction in blood pressure of 22 mm Hg, 21.33 mm Hg, and 21.33 mm Hg, respectively, while lisinopril promoted a maximum reduction of 51.00 mm Hg. These results suggest that the commercial collagen hydrolysates of bovine and porcine origin may be a potential source of bioactive peptides. PMID:18800907

Faria, Mariza; da Costa, Elizabete Lourenço; Gontijo, José Antônio Rocha; Netto, Flávia Maria

2008-09-01

329

Production of goat milk protein hydrolysate enriched in ACE-inhibitory peptides by ultrafiltration.  

PubMed

A global process for the production of goat milk hydrolysates enriched in angiotensin converting enzyme (ACE) inhibitory peptides was proposed. Firstly, the protein fractions (caseins and whey proteins) were separated by ultrafiltration through a 0·14 ?m ceramic membrane. The casein fraction obtained in the retentate stream of the above filtration step was subsequently hydrolysed with a combination of subtilisin and trypsin. After 3 h of reaction, the hydrolysate produced presented an IC50 of 218·50 ?g/ml, which represent a relatively high ACE inhibitory activity. Finally, this hydrolysate was filtered through a 50 kDa ceramic membrane until reaching a volume reduction factor of 3. The permeate produced presented an improvement of more than 30% in the ACE inhibitory activity. In contrast, the retentate was concentrated in larger and inactive peptides which led to a decrease of more than 80% in its inhibitory activity. The process suggested in this work was suitable to obtain a potent ACE inhibitory activity product able to be incorporated into food formulas intended to control or lower blood pressure. Moreover, the liquid product could be easily stabilised by spray dried if it would be necessary. PMID:25003564

Espejo-Carpio, Francisco Javier; Pérez-Gálvez, Raúl; Almécija, María Del Carmen; Guadix, Antonio; Guadix, Emilia M

2014-11-01

330

Xylose utilizing Zymomonas mobilis with improved ethanol production in biomass hydrolysate medium  

DOEpatents

Xylose-utilizing, ethanol producing strains of Zymomonas mobilis with improved performance in medium comprising biomass hydrolysate were isolated using an adaptation process. Independently isolated strains were found to have independent mutations in the same coding region. Mutation in this coding may be engineered to confer the improved phenotype.

Caimi, Perry G; Hitz, William D; Viitanen, Paul V; Stieglitz, Barry

2013-10-29

331

Xylose utilizing zymomonas mobilis with improved ethanol production in biomass hydrolysate medium  

DOEpatents

Xylose-utilizing, ethanol producing strains of Zymomonas mobilis with improved performance in medium comprising biomass hydrolysate were isolated using an adaptation process. Independently isolated strains were found to have independent mutations in the same coding region. Mutation in this coding may be engineered to confer the improved phenotype.

Caimi, Perry G; Hitz, William D; Stieglitz, Barry; Viitanen, Paul V

2013-07-02

332

Processing poultry feathers into keratin hydrolysate through alkaline-enzymatic hydrolysis.  

PubMed

Poultry feathers make up for as much as 8.5% of chicken weight and represent a considerable amount of almost pure keratin waste which is not being adequately utilized at the present time. The present study dealt with the processing of poultry feathers through a two-stage alkaline-enzymatic hydrolysis. In the first stage, feathers were mixed with a 0.1 or 0.3% KOH water solution in a 1 : 50 ratio and were incubated at 70°C for 24 h. After adjusting pH to 9, the effects examined in the second processing stage on the amount of degraded feathers were those of proteolytic enzyme additions (1-5%), time (4-8 h) and temperature (50-70°C). Processing feathers in 0.3% KOH and hydrolysing for 8 h in the second stage at 70°C with a 5% dose of enzyme (relative to dry feathers weight) produced approx. 91% degradation. Keratin hydrolysate is distinct for its high nitrogen content and reasonable inorganic solids level. Two-stage technology of alkaline-enzymatic hydrolysing of poultry feathers in an environment of 0.3% KOH achieves high efficiency under quite mild reaction conditions (temperature not exceeding 70°C with pH in a mildly alkaline region), and is feasible from an economic viewpoint. Keratin hydrolysate can find particular application in packaging technology (films, foils and encapsulates). PMID:20483878

Mokrejs, Pavel; Svoboda, Petr; Hrncirik, Josef; Janacova, Dagmar; Vasek, Vladimir

2011-03-01

333

Anticancer camptothecin-N-poly(lactic acid) nanoconjugates with facile hydrolysable linker  

E-print Network

Anticancer camptothecin-N-poly(lactic acid) nanoconjugates with facile hydrolysable linker Qian Yin and enhanced lactone stability.6�9 Polymeric nanomedicine, an emerging eld that includes the use of drug�14 Utilizing polymeric NPs as drug carriers to deliver CPT has the potential to provide various benets

Cheng, Jianjun

334

In vivo and in vitro evaluation of the residual allergenicity of partially hydrolysed infant formulas.  

PubMed

Hypoallergenic infant formulas are commonly used for genetically predisposed children and infants diagnosed with cow's milk allergy. This study describes both in vitro and in vivo approaches to assess residual allergenicity of partially hydrolysed infant formulas. Electrophoretic patterns indicated that ?-lactoglobulin and other whey proteins were largely degraded. For safety reasons, according to the European commission-guidelines, it is required that the sensitizing capacity of hypoallergenic formulas is tested in an animal model. In contrast to whey sensitization, no elevated levels of whey-specific IgE, anaphylactic reactions or drop in body temperature were observed in sensitized mice exposed to whey hydrolysates. This indicates that the whey hydrolysates lost their putative sensitizing capacity in a mouse model using oral sensitization, which is highly relevant in relation to the human situation. In combination with the lost capacity of hydrolysed infant formulas to cross-link human IgE antibodies on RBL-huFc?RI in vitro, both the sensitization and the challenge phase of the allergic response were studied. This combination of assays is proposed as a strategy for the screening of new hypoallergenic formulas aimed at preventing sensitization in atopic children and avoiding clinical symptoms in infants suffering from cow's milk allergy. PMID:21251954

van Esch, Betty C A M; Knipping, Karen; Jeurink, Prescilla; van der Heide, Sicco; Dubois, Anthony E J; Willemsen, Linette E M; Garssen, Johan; Knippels, Léon M J

2011-03-25

335

Poly(vinyl alcohol)–collagen hydrolysate thermoplastic blends: I. Experimental design optimisation and biodegradation behaviour  

Microsoft Academic Search

Hybrid blends based on poly(vinyl alcohol) (PVA) and collagen hydrolysate (CH), an abundant, added value waste product of the leather industry, have been processed by melt blow extrusion to environmentally degradable films. Optimisation of the blend compositions was performed in respect of mechanical properties of the films. The experimental design method (DOE) was used for the understanding of the structure–property

P. Alexy; D. Bakoš; S. Hanzelová; L. Kukolíková; J. Kupec; K. Charvátová; E. Chiellini; P. Cinelli

2003-01-01

336

Protein Hydrolysates Are Avoided by Herbivores but Not by Omnivores in Two-Choice Preference Tests  

Microsoft Academic Search

Background: The negative sensory properties of casein hydrolysates (HC) often limit their usage in products intended for human consumption, despite HC being nutritious and having many functional benefits. Recent, but taxonomically limited, evidence suggests that other animals also avoid consuming HC when alternatives exist. Methodology\\/Principal Findings: We evaluated ingestive responses of five herbivorous species (guinea pig, mountain beaver, gopher, vole,

Kristin L. Field; Alexander A. Bachmanov; Julie A. Mennella; Gary K. Beauchamp; Bruce A. Kimball

2009-01-01

337

linkage between a phenolic acid and the carbohydrate of hydrolysable tannins.  

E-print Network

at an internal peptide derived from Endo-Lys C hydrolysis and HPLC purifi- cation. From the amino acid sequence. Purified enzyme has been obtained and 13 amino acids were se- quenced at the N terminus and 10 amino acidslinkage between a phenolic acid and the carbohydrate of hydrolysable tannins. TAH has

Paris-Sud XI, Université de

338

Speciation of chromium in chromium yeast.  

PubMed

High-performance liquid chromatography was used to separate Cr(III) and Cr(VI) in samples with detection by inductively coupled plasma mass spectrometry(ICP-MS). The separation was achieved on a weak anion exchange column. The mobile phase was pH 7.0 ammonium nitrate solution. The redox reaction between Cr(III) and Cr(VI) was avoided during separation and determination. This separation method could be used to separate the samples with large concentration differences between Cr(III) and Cr(VI). The alkaline digestion was used to extract chromium in solid sample, which had no effect on the retention time and the peak area of the Cr(VI). However, the conversion of Cr(VI) from Cr(III) was observed during alkaline digestion, which displayed positive relation with the ratio of Cr(III) and Cr(VI) in samples. Both Cr(III) and Cr(VI) contents of chromium yeasts cultured in media with different chromium additions were determined. The spike recoveries of Cr(VI) for chromium yeasts were in the range of 95-108 %. PMID:25269546

Guo, Xuena; Liu, Wei; Bai, Xuejing; He, Xiuping; Zhang, Borun

2014-12-01

339

A new insight into resource recovery of excess sewage sludge: feasibility of extracting mixed amino acids as an environment-friendly corrosion inhibitor for industrial pickling.  

PubMed

The work mainly presented a laboratory-scale investigation on an effective process to extract a value-added product from municipal excess sludge. The functional groups in the hydrolysate were characterized with Fourier transform infrared spectrum, and the contained amino acids were measured by means of an automatic amino acid analyzer. The corrosion-inhibition characteristics of the hydrolysate were determined with weight-loss measurement, electrochemical polarization and scanning electron microscopy. Results indicated that the hydrolysate contained 15 kinds of amino acid, and their adsorption on the surface could effectively inhibit the corrosion reaction of the steel from the acid medium. Polarization curves indicated that the obtained hydrolysate was a mixed-type inhibitor, but mainly restricted metal dissolution on the anode. The adsorption accorded well with the Langmuir adsorption isotherm, involved an increase in entropy, and was a spontaneous, exothermic process. PMID:25036999

Su, Wen; Tang, Bing; Fu, Fenglian; Huang, Shaosong; Zhao, Shiyuan; Bin, Liying; Ding, Jiewei; Chen, Cuiqun

2014-08-30

340

Chitin extraction from shrimp shell waste using Bacillus bacteria.  

PubMed

The ability of six protease-producing Bacillus species (Bacillus pumilus A1, Bacillus mojavencis A21, Bacillus licheniformis RP1, Bacillus cereus SV1, Bacillus amyloliquefaciens An6 and Bacillus subtilis A26) to ferment media containing only shrimp shell waste, for chitin extraction, was investigated. More than 80% deproteinization was attained by all the strains tested. However, demineralization rates not exceeding 67% were registered. Cultures conducted in media containing shrimp shell waste supplemented with 5% (w/v) glucose were found to remarkably promote demineralization efficiency, without affecting deproteinization rates. The antioxidant activities of hydrolysates, at different concentrations, produced during fermentation in medium supplemented with glucose, were determined using different tests: 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical-scavenging method, reducing power assay and chelating activity. All hydrolysates showed varying degrees of antioxidant activity. Hydrolysate produced by B. pumilus A1 exhibited the highest DPPH radical scavenging activity, with an IC(50) value of 0.3 mg/ml. Highest reducing power (DO 700 nm=1.55 at 1.5 mg/ml) and metal chelating activity (98% at 5mg/ml) were obtained with B. pumilus A1 and B. licheniformis RP1 hydrolysates, respectively. PMID:22981824

Ghorbel-Bellaaj, Olfa; Younes, Islem; Maâlej, Hana; Hajji, Sawssen; Nasri, Moncef

2012-12-01

341

Re-assessment of YAP1 and MCR1 contributions to inhibitor tolerance in robust engineered Saccharomyces cerevisiae fermenting undetoxified lignocellulosic hydrolysate.  

PubMed

Development of robust yeast strains that can efficiently ferment lignocellulose-based feedstocks is one of the requirements for achieving economically feasible bioethanol production processes. With this goal, several genes have been identified as promising candidates to confer improved tolerance to S. cerevisiae. In most of the cases, however, the evaluation of the genetic modification was performed only in laboratory strains, that is, in strains that are known to be quite sensitive to various types of stresses. In the present study, we evaluated the effects of overexpressing genes encoding the transcription factor (YAP1) and the mitochondrial NADH-cytochrome b5 reductase (MCR1), either alone or in combination, in an already robust and xylose-consuming industrial strain of S. cerevisiae and evaluated the effect during the fermentation of undiluted and undetoxified spruce hydrolysate. Overexpression of either gene resulted in faster hexose catabolism, but no cumulative effect was observed with the simultaneous overexpression. The improved phenotype of MCR1 overexpression appeared to be related, at least in part, to a faster furaldehyde reduction capacity, indicating that this reductase may have a wider substrate range than previously reported. Unexpectedly a decreased xylose fermentation rate was also observed in YAP1 overexpressing strains and possible reasons behind this phenotype are discussed. PMID:25147754

Wallace-Salinas, Valeria; Signori, Lorenzo; Li, Ying-Ying; Ask, Magnus; Bettiga, Maurizio; Porro, Danilo; Thevelein, Johan M; Branduardi, Paola; Foulquié-Moreno, María R; Gorwa-Grauslund, Marie

2014-01-01

342

Nuclear transport of yeast proteasomes.  

PubMed

Proteasomes are conserved protease complexes enriched in the nuclei of dividing yeast cells, a major site for protein degradation. If yeast cells do not proliferate and transit to quiescence, metabolic changes result in the dissociation of proteasomes into proteolytic core and regulatory complexes and their sequestration into motile cytosolic proteasome storage granuli. These granuli rapidly clear with the resumption of growth, releasing the stored proteasomes, which relocalize back to the nucleus to promote cell cycle progression. Here, I report on three models of how proteasomes are transported from the cytoplasm into the nucleus of yeast cells. The first model applies for dividing yeast and is based on the canonical pathway using classical nuclear localization sequences of proteasomal subcomplexes and the classical import receptor importin/karyopherin ??. The second model applies for quiescent yeast cells, which resume growth and use Blm10, a HEAT-like repeat protein structurally related to karyopherin ?, for nuclear import of proteasome core particles. In the third model, the fully-assembled proteasome is imported into the nucleus. Our still marginal knowledge about proteasome dynamics will inspire the discussion on how protein degradation by proteasomes may be regulated in different cellular compartments of dividing and quiescent eukaryotic cells. PMID:25333764

Enenkel, Cordula

2014-01-01

343

An inter-laboratory evaluation of selective media for the detection and enumeration of yeasts from blue-veined cheese.  

PubMed

Five countries representative of laboratories 1-5 evaluated 11 different selective media, designed to suppress mould and bacterial growth and support yeasts growth, for the recovery of yeast populations from blue veined cheeses. In addition, qualitative results were also incorporated. The yeast enumeration values were subjected to statistical analysis using analysis of variance (ANOVA) and the Tukey-Kramer multiple comparison test. With the exception of Laboratory 3, none of the other laboratories was successful in recovering yeasts on all the media. Six of the media proved inadequate for the enumeration of yeasts in the mould invested environment and were therefore omitted from statistical analysis. No significant differences in quantitative data obtained on Rose-Bengal Chloramphenicol Agar (RBCA), Dichloran Rose-Bengal Chloramphenicol Agar (DRBC), Dichloran 18% Glycerol Agar (DG18), and Malt extract agar supplemented with NaCl and oxytetracycline (MES) were detected by four of the collaborating laboratories whereas one laboratory found RBCA to be superior for yeast enumeration. DG18 and Malt Extract Agar with Biphenyl (MEB), however, were ranked superior based on qualitative results compared to the other media, attributed to distinctive individual yeast colonies and mould inhibition. RBCA, DRBC, DG18, and MES on the other hand, all proved to be adequate in supporting yeast colony development for quantitative analysis in samples obtained from blue veined cheeses. PMID:15172480

Viljoen, B C; Knox, A; Beuchat, L R; Deak, T; Malfeito-Ferreira, M; Hansen, T K; Hugo, A; Jakobsen, M; Loureiro, V; Lourens-Hattingh, A; Vasdinnyei, R

2004-07-01

344

Cdc42 Oscillations in Yeasts  

NSDL National Science Digital Library

A fundamental problem in cell biology is how cells define one or several discrete sites of polarity. Through mechanisms involving positive and negative feedback, the small Rho-family guanosine triphosphatase Cdc42 breaks symmetry in round budding yeast cells to define a single site of polarized cell growth. However, it is not clear how cells can define multiple sites of polarization concurrently. We discuss a study in which rod-shaped fission yeast cells, which naturally polarize growth at their two cell ends, exhibited oscillations of Cdc42 activity between these sites. We compare these findings with similar oscillatory behavior of Cdc42 detected in budding yeast cells and discuss the possible mechanism and functional outputs of these oscillations.

Felipe O. Bendezu (Switzerland;University of Lausanne REV); Sophie G. Martin (Switzerland;University of Lausanne REV)

2012-12-04

345

The yeasts of cheese brines.  

PubMed

A total of 365 yeasts were isolated from the brines of soft, semihard and hard cheeses from different manufacturers. Identification was based on 131 characteristics, primarily employing a method with microtitration plates. Most brines exhibited a characteristic yeast flora. The predominant strains proved to be mainly Debaryomyces hansenii and Candida versatilis. In a few brines Trichosporon beigelii, C. rugosa, C. intermedia, Kluyveromyces marxianus, Saccharomyces sp. and C. tenuis/polymorpha were predominant. Also of importance were C. tropicalis, C. parapsilosis, C. zeylanoides, Issatchenkia orientalis and Geotrichum klebahnii. Not all strains could be clearly identified. Lists of characters are provided for subdividing D. hansenii and T. beigelii. The specificity of the yeast flora of brines is assumed to contribute to the sensory variety of cheeses. PMID:2282287

Seiler, H; Busse, M

1990-12-01

346

280 EXPRESSION IN YEAST [23] [23] Manipulating Yeast Genome Using Plasmid Vectors  

E-print Network

280 EXPRESSION IN YEAST [23] [23] Manipulating Yeast Genome Using Plasmid Vectors By TIM STEARNS, HONG MA, and DAVID BOTSTEIN The yeast Saccharomyces cerevisiae has proved to be a popular high status of yeast as an experimental system is in large part due to the work of the many geneticists

Botstein, David

347

APPENDIX 4LGrowth and Manipulation of Yeast PREPARATION OF SELECTED YEAST MEDIA  

E-print Network

APPENDIX 4LGrowth and Manipulation of Yeast PREPARATION OF SELECTED YEAST MEDIA Like Escherichia coli, yeast can be grown in either liquid media or on the surface of (or embedded in) solid agar plates. Yeast cells grow well on a minimal medium containing dextrose (glucose) as a carbon source and salts

Winston, Fred

348

Pre-Absorbing Antibody with Yeast Cells Preparation of Fixed Yeast  

E-print Network

106 Pre-Absorbing Antibody with Yeast Cells Preparation of Fixed Yeast 1. Plan to do steps 1-10 in the yeast immunofluorescence method. But, start with 100 mls of cells at OD600=0.2. Then, do all steps in quadruplicate. Do pretreatment, and digest cells for 10 minutes. 2. Pool all yeast in SPC + Pics in one

Aris, John P.

349

The Yeast Nuclear Pore Complex  

PubMed Central

An understanding of how the nuclear pore complex (NPC) mediates nucleocytoplasmic exchange requires a comprehensive inventory of the molecular components of the NPC and a knowledge of how each component contributes to the overall structure of this large molecular translocation machine. Therefore, we have taken a comprehensive approach to classify all components of the yeast NPC (nucleoporins). This involved identifying all the proteins present in a highly enriched NPC fraction, determining which of these proteins were nucleoporins, and localizing each nucleoporin within the NPC. Using these data, we present a map of the molecular architecture of the yeast NPC and provide evidence for a Brownian affinity gating mechanism for nucleocytoplasmic transport. PMID:10684247

Rout, Michael P.; Aitchison, John D.; Suprapto, Adisetyantari; Hjertaas, Kelly; Zhao, Yingming; Chait, Brian T.

2000-01-01

350

Chromatin and Transcription in Yeast  

PubMed Central

Understanding the mechanisms by which chromatin structure controls eukaryotic transcription has been an intense area of investigation for the past 25 years. Many of the key discoveries that created the foundation for this field came from studies of Saccharomyces cerevisiae, including the discovery of the role of chromatin in transcriptional silencing, as well as the discovery of chromatin-remodeling factors and histone modification activities. Since that time, studies in yeast have continued to contribute in leading ways. This review article summarizes the large body of yeast studies in this field. PMID:22345607

Rando, Oliver J.; Winston, Fred

2012-01-01

351

Application in the Ethanol Fermentation of Immobilized Yeast Cells in Matrix of Alginate/Magnetic Nanoparticles, on Chitosan-Magnetite Microparticles and Cellulose-coated Magnetic Nanoparticles  

E-print Network

Saccharomyces cerevisiae cells were entrapped in matrix of alginate and magnetic nanoparticles and covalently immobilized on magnetite-containing chitosan and cellulose-coated magnetic nanoparticles. Cellulose-coated magnetic nanoparticles with covalently immobilized thermostable {\\alpha}-amylase and chitosan particles with immobilized glucoamylase were also prepared. The immobilized cells and enzymes were applied in column reactors - 1/for simultaneous corn starch saccharification with the immobilized glucoamylase and production of ethanol with the entrapped or covalently immobilized yeast cells, 2/ for separate ethanol fermentation of the starch hydrolysates with the fixed yeasts. Hydrolysis of corn starch with the immobilized {\\alpha}-amylase and glucoamylase, and separate hydrolysis with the immobilized {\\alpha}-amylase were also examined. In the first reactor the ethanol yield reached approx. 91% of the theoretical; the yield was approx. 86% in the second. The ethanol fermentation was affected by the typ...

Ivanova, Viara; Hristov, Jordan

2011-01-01

352

Production of butanol (a biofuel) from agricultural residues: Part II – Use of corn stover and switchgrass hydrolysates  

Microsoft Academic Search

Acetone butanol ethanol (ABE) was produced from hydrolysed corn stover and switchgrass using Clostridium beijerinckii P260. A control experiment using glucose resulted in the production of 21.06 g L?1 total ABE. In this experiment an ABE yield and productivity of 0.41 and 0.31 g L?1 h?1 was achieved, respectively. Fermentation of untreated corn stover hydrolysate (CSH) exhibited no growth and no ABE production; however, upon

Nasib Qureshi; Badal C. Saha; Ronald E. Hector; Bruce Dien; Stephen Hughes; Siqing Liu; Loren Iten; Michael J. Bowman; Gautam Sarath; Michael A. Cotta

2010-01-01

353

Influence of dicamba and casein hydrolysate on somatic embryo number and culture quality in cell suspensions of Dactylis glomerata (Gramineae)  

Microsoft Academic Search

The effects of various concentrations and combinations of dicamba (3,6-dichloro-o-anisic acid) and casein hydrolysate on growth, mucilage accumulation, somatic embryo and root development in suspension cultures of Dactylis glomerata L. (orchardgrass) were examined. Fresh weight of culture tissue was increased with 20 µM but not with 80 or 160 µM dicamba in treatments with 1–4 g\\/l casein hydrolysate. Different casein

D. J. Gray; B. V. Conger

1985-01-01

354

Chemical, microbiological and plant analysis of soil fertilized with alkaline hydrolysate of sheep’s wool waste  

Microsoft Academic Search

Summary  The effect of adding alkaline hydrolysate of sheep’s wool waste on the chemical and microbiological properties of a park soil\\u000a (Sofia, Bulgaria) has been assessed in a 9 month laboratory experiment. The waste product contained 75–80% water-soluble materials:\\u000a peptides, amino acids, salts, dyes, lipids, some carbohydrates, potassium ions, and it seemed likely that the hydrolysate\\u000a obtained could be used as a

Maya Nustorova; Diana Braikova; Adriana Gousterova; Evgenia Vasileva-Tonkova; Peter Nedkov

2006-01-01

355

APPLICATION OF EXPERIMENTAL DESIGN METHOD FOR ETHANOL PRODUCTION BY FERMENTATION OF SUNFLOWER SEED HULL HYDROLYSATE USING PICHIA STIPITIS NRRL-124  

Microsoft Academic Search

The lignocellulosic hydrolysates provide a rich medium for fermentation of sugars into ethanol. The potential use of sunflower seed hull hemicellulose hydrolysate in ethanol fermentation was evaluated by using the Experimental Design method in this study. A 2 Box-Wilson experimental design was used to develop a statistical model. The effects of shaking rate (55–145 rpm) and initial pH (4.6–7.4) on the

Odonchimeg Jargalsaikhan; Nurdan Saraço?lu

2008-01-01

356

Anti-cyclooxygenase effects of lipid extracts from the New Zealand green-lipped mussel, Perna canaliculus  

Microsoft Academic Search

Total lipid extracts of P. canaliculus (a bivalve marine mollusc native to New Zealand, commonly called the green-lipped mussel) and Mytilus edulis (commonly called the common blue mussel) moderately inhibited ovine COX-1 and COX-2 pure enzymes in vitro. The inhibition was increased after the mussel extracts were saponified by KOH hydrolysis. Protease- and protease–lipase-hydrolysed lipid extracts of P. canaliculus exhibited

S. McPhee; L. D. Hodges; P. F. A. Wright; P. M. Wynne; N. Kalafatis; D. W. Harney; T. A. Macrides

2007-01-01

357

Hypolipidimic and antioxidant activities of oleuropein and its hydrolysis derivative-rich extracts from Chemlali olive leaves  

Microsoft Academic Search

Oleuropein-rich extracts from olive leaves and their enzymatic and acid hydrolysates, respectively rich in oleuropein aglycone and hydroxytyrosol, were prepared under optimal conditions. The antioxidant activities of these extracts were examined by a series of models in vitro. In this study the lipid-lowering and the antioxidative activities of oleuropein, oleuropein aglycone and hydroxytyrosol-rich extracts in rats fed a cholesterol-rich diet

Hedya Jemai; Mohamed Bouaziz; Ines Fki; Abdelfattah El Feki; Sami Sayadi

2008-01-01

358

A New Approach to the Isolation of Genomic DNA from Yeast and Fungi: Preparation of DNA-containing Cell Envelopes and Their Use in PCR  

Microsoft Academic Search

A simple and rapid procedure for the preparation of yeast and fungal DNA samples useful in PCR amplification was developed. The DNA was purified from proteins, lipids, polysaccharides, and other impurities by high-temperature extraction (in a boiling water bath) with buffer solutions containing chaotropic salts. Under these conditions, yeast and fungal cell envelopes remain unbroken and retain the original DNA

V. N. Danilevich; E. V. Grishin

2002-01-01

359

Modelling the Yeast Interactome Vuk Janjic1  

E-print Network

Modelling the Yeast Interactome Vuk Janjic´1 , Roded Sharan2 & Natasa Przulj1 1 Department of any empirical observation regarding those networks. Here, we perform a comprehensive analysis of yeast complexity (human and yeast); (3) clear topological difference is present between PPI networks

Shamir, Ron

360

Yeast communities associated with stingless bees  

Microsoft Academic Search

The yeast communities associated with the stingless bees Tetragonisca angustula, Melipona quadrifasciata and Frieseomelitta varia were studied. The bees T. angustula and F. varia showed a strong association with the yeast Starmerella meliponinorum. M. quadrifasciata more frequently carried a species related to Candida apicola, but also vectored low numbers of S. meliponinorum. Some of the yeasts isolated from adult bees

Carlos A Rosa; Marc-André Lachance; Jana??na O. C Silva; Ana Carolina P Teixeira; Marjorie M Marini; Yasmine Antonini; Rogerio P Martins

2003-01-01

361

Red yeast rice: a new hypolipidemic drug  

Microsoft Academic Search

Red yeast rice is a source of fermented pigment with possible bioactive effect. Evidence shows that fermented red yeast rice lowers cholesterol levels moderately compared to other statin drugs, but with the added advantage of causing less adverse effects. A review of the body of evidence surrounding the properties of red yeast rice underscores its potential as a new alternative

Mélanie Journoud; Peter J. H Jones

2004-01-01

362

Yeast community survey in the Tagus estuary  

Microsoft Academic Search

The yeast community in the waters of the Tagus estuary, Portugal, was followed for over a year in order to assess its dynamics. Yeast occurrence and incidence were measured and this information was related to relevant environmental data. Yeast occurrence did not seem to depend upon tides, but river discharge had a dramatic impact both on the density and diversity

João M. G. C. F. de Almeida

2005-01-01

363

Enzymatic process for the fractionation of baker's yeast cell wall (Saccharomyces cerevisiae).  

PubMed

?-Glucans, homopolymers of glucose, are widespread in many microorganisms, mushrooms and plants. They have attracted attention because of their bioactive and medicinal functions. One important source of ?-glucans is the cell wall of yeasts, especially that of baker's yeast Saccharomyces cerevisiae. Several processes for the isolation of ?-glucans, using alkali, acid or a combination of both, result in degradation of the polymeric chains. In this paper, we have an enzymatic process for the isolation of glucans from yeast cell walls. As a result, ?-glucans were obtained in a yield of 18.0% of the original ratio in the yeast cell walls. Therefore, this isolation process gave a better yield and higher ?-glucan content than did traditional isolation methods. Furthermore, results showed that each extraction step of ?-glucan had a significant effects on its chemical properties. PMID:24912704

Borchani, Chema; Fonteyn, Fabienne; Jamin, Guilhem; Paquot, Michel; Blecker, Christophe; Thonart, Philippe

2014-11-15

364

Yeast effects on Pinot noir wine phenolics, color, and tannin composition.  

PubMed

Extraction and stabilization of wine phenolics can be challenging for wine makers. This study examined how yeast choice affected phenolic outcomes in Pinot noir wine. Five yeast treatments were applied in replicated microvinification, and wines were analyzed by UV-visible spectrophotometry. At bottling, yeast treatment Saccharomyces cerevisiae RC212 wine had significantly higher concentrations of total pigment, free anthocyanin, nonbleachable pigment, and total tannin and showed high color density. Some phenolic effects were retained at 6 months' bottle age, and RC212 and S. cerevisae EC1118 wines showed increased mean nonbleachable pigment concentrations. Wine tannin composition analysis showed three treatments were associated with a higher percentage of trihydroxylated subunits (skin tannin indicator). A high degree of tannin polymerization was observed in wines made with RC212 and Torulaspora delbruekii , whereas tannin size by gel permeation chromatography was higher only in the RC212 wines. The results emphasize the importance of yeast strain choice for optimizing Pinot noir wine phenolics. PMID:24011384

Carew, Anna L; Smith, Paul; Close, Dugald C; Curtin, Chris; Dambergs, Robert G

2013-10-16

365

Feature extraction Feature extraction  

E-print Network

(hyperspectral sensors) Meteosat thermal IR channel hyperspectral "image cube" #12;Raw intensities · ProsFeature extraction #12;Feature extraction · Image interpretation: extract information from images · but the desired information may not be explicit in the raw observed pixel intensities · Transform image to make

Giger, Christine

366

Feature extraction Feature extraction  

E-print Network

(hyperspectral sensors) Meteosat thermal IR channel hyperspectral "image cube" #12;Raw intensities ! � ProsFeature extraction #12;Feature extraction ! � Image interpretation: extract information from images � but the desired information may not be explicit in the raw observed pixel intensities � Transform image to make

Giger, Christine

367

Surface display of a bifunctional glutathione synthetase on Saccharomyces cerevisiae for converting chicken feather hydrolysate into glutathione.  

PubMed

The low economic profits of feather recycling lead that the large amount of feathers is currently discarded in China. To convert feather hydrolysates into GSH with high values, surface display of the bifunctional glutathione synthetase encoded by gcsgs from Streptococcus thermophilus on Saccharomyces cerevisiae and the potential in glutathione (GSH) production from feather hydrolysates were studied. The surface-displayed GCSGS could be used to convert feather hydrolysates into GSH. Results showed that 10 g/l of feather was converted into 321.8 mg/l GSH by the Trichoderma atroviride F6 and surface-displayed GCSGS in the study. Compared with production of intracellular GSH by S. cerevisiae from amino acids or feather hydrolysate, the concentration of GSH in the study was higher, and purification of GSH was more feasible. Due to the glycolytic pathway, the S. cerevisiae was used to generate ATP and cheap feather hydrolysate as precursors, the process for GSH production based on surface-displayed GCSGS is cheap and feasible. The process showed the potential to convert feather hydrolysates into GSH on an industrial scale. PMID:24706360

Qiu, Zhiqi; Tan, Hongming; Zhou, Shining; Cao, Lixiang

2014-08-01

368

Kinetic modeling of batch fermentation for Populus hydrolysate tolerant mutant and wild type strains of Clostridium thermocellum.  

PubMed

The extent of inhibition of two strains of Clostridium thermocellum by a Populus hydrolysate was investigated. A Monod-based model of wild type (WT) and Populus hydrolysate tolerant mutant (PM) strains of the cellulolytic bacterium C. thermocellum was developed to quantify growth kinetics in standard media and the extent of inhibition to a Populus hydrolysate. The PM was characterized by a higher growth rate (?max=1.223 vs. 0.571 h(-1)) and less inhibition (KI,gen=0.991 vs. 0.757) in 10% v/v Populus hydrolysate compared to the WT. In 17.5% v/v Populus hydrolysate inhibition of PM increased slightly (KI,gen=0.888), whereas the WT was strongly inhibited and did not grow in a reproducible manner. Of the individual inhibitors tested, 4-hydroxybenzoic acid was the most inhibitory, followed by galacturonic acid. The PM did not have a greater ability to detoxify the hydrolysate than the WT. PMID:24036527

Linville, Jessica L; Rodriguez, Miguel; Mielenz, Jonathan R; Cox, Chris D

2013-11-01

369

Biotechnological production of xylitol: enhancement of monosaccharide production by post-hydrolysis of dilute acid sugarcane hydrolysate.  

PubMed

Dilute-acid hydrolysis pretreatment of sugarcane bagasse resulted in release of 48% (18.4 g/L) of the xylan in the hemicellulose fraction into the hydrolysate as monomeric xylose. In order to enhance the recuperation of this monomer, a post-hydrolysis stage consisted of thermal treatment was carried out. This treatment resulted in an increase in xylose release of 62% (23.5 g/L) of the hemicellulose fraction. Original and post-hydrolysates were concentrated to the same levels of monomeric xylose in the fermentor feed. During the fermentation process, cellular growth was observed to be higher in the post-hydrolysate (3.5 g/L, Y(x/s) = 0.075 g cells/g xylose) than in the original hydrolysate (2.9 g/L, Y(x/s) = 0.068 g cells/g xylose). The post-treated hydrolysate required less concentration of sugars resulting in a lower concentration of fermentation inhibitors, which were formed primarily in the dilute acid hydrolysis step. Post-hydrolysis step led to a high xylose-xylitol conversion efficiency of 76% (0.7 g xylitol/g xylose) and volumetric productivity of 0.68 g xylitol/L h when compared to 71% (0.65 g xylitol/g xylose and productivity of 0.61 g xylitol/L h) for the original hemicellulosic hydrolysate. PMID:19214792

Sarrouh, Boutros Fouad; de Freitas Branco, Ricardo; da Silva, Silvio Silvério

2009-05-01

370

In vivo methods for testing allergenicity show that high hydrostatic pressure hydrolysates of ?-lactoglobulin are immunologically inert.  

PubMed

The major milk allergen ?-lactoglobulin (?-LG) exhibits an enhanced susceptibility to proteolysis under high hydrostatic pressure and this may be an efficient method to produce hypoallergenic hydrolysates. The aim of this work was to evaluate the in vivo allergenicity of 3 ?-LG hydrolysates produced under atmospheric pressure or high-pressure conditions. Hydrolysates were chosen based on previous experiments that showed that they provide a complete removal of intact ?-LG but differed in vitro IgE-binding properties that could be traced to the peptide pattern. The ability to trigger systemic anaphylaxis was assessed using C3H/HeJ mice orally sensitized to ?-LG. Outcome measures included symptom score, body temperature, serum mouse mast cell protease 1 (mMCP-1), and quantification of circulating basophils. Mast cell degranulation in vivo was assessed by passive cutaneous anaphylaxis. The 3 tested hydrolysates showed an abrogated allergenicity as revealed by the absence of anaphylactic symptoms and a decrease in body temperature. We demonstrated that the peptides present in the hydrolysates had lost their ability to cross-link 2 human IgE antibodies to induce mast cell degranulation, thus indicating that most of the peptides formed retain just one relevant IgE-binding epitope. The orally sensitized mouse model is a useful tool to address the in vivo allergenicity of novel milk formulas and demonstrates the safety of hydrolysates produced under high-pressure conditions. PMID:22281318

López-Expósito, I; Chicón, R; Belloque, J; López-Fandiño, R; Berin, M C

2012-02-01

371

Maximizing the xylitol production from sugar cane bagasse hydrolysate by controlling the aeration rate  

SciTech Connect

Batch fermentations of sugar cane bagasse hemicellulosic hydrolysate treated for removing the inhibitors of the fermentation were performed by Candida guilliermondii FTI 20037 for xylitol production. The fermentative parameters agitation and aeration rate were studied aiming the maximization of xylitol production from this agroindustrial residue. The maximal xylitol volumetric productivity (0.87 g/L {center_dot} h) and yield (0.67 g/g) were attained at 400/min and 0.45 v.v.m. (K{sub L}a 27/h). According to the results, a suitable control of the oxygen input permitting the xylitol formation from sugar cane bagasse hydrolysate is required for the development of an efficient fermentation process for large-scale applications. 20 refs., 2 figs.

Silva, S.S.; Ribeiro, J.D.; Felipe, M.G.A. [Faculty of Chemical Enginering of Lorena (Brazil); Vitolo, M. [Univ. of Sao Paulo (Brazil)

1997-12-31

372

Tobacco biomass hydrolysate enhances coenzyme Q10 production using photosynthetic Rhodospirillum rubrum.  

PubMed

Coenzyme Q10 (CoQ10), a potent antioxidative dietary supplement, was produced using a photosynthetic bacteria Rhodospirillum rubrum ATCC 25852 by submerged fermentation supplemented with tobacco biomass hydrolysate (TBH) in comparison with media supplemented with hydrolysates prepared with alfalfa (ABH) or spinach (SBH). Growth medium supplemented with 20% (v/v) TBH was found favorable with regard to cell density and CoQ10 concentration. The stimulation effects on cell growth (shortened lag phase, accelerated exponential growth, and elevated final cell concentration) and CoQ10 production (enhanced specific CoQ10 content per unit cell weight) could be attributed to the presence of solanesol, the precursor of CoQ10, in the tobacco biomass. The final yield of CoQ10 reached 20.16 mg/l in the fermentation medium supplemented with 20% TBH. PMID:20554198

Tian, Yuting; Yue, Tianli; Yuan, Yahong; Soma, Pavan K; Williams, Patrick D; Machado, Peter A; Fu, Hong; Kratochvil, Robert J; Wei, Cheng-I; Lo, Y Martin

2010-10-01

373

L-lactate production from seaweed hydrolysate of Laminaria japonica using metabolically engineered Escherichia coli.  

PubMed

Renewable and carbon neutral, marine algal biomass could be an attractive alternative substrate for the production of biofuel and various biorefinery products. Thus, the feasibility of brown seaweed (Laminaria japonica) hydrolysate as a carbon source was investigated here for L-lactate production. This work reports the homofermentative route for L-lactate production by introducing Streptococcus bovis/equinus L-lactate dehydrogenase in an engineered Escherichia coli strain where synthesis of the competing by-product was blocked. The engineered strain utilized both glucose and mannitol present in the hydrolysate under microaerobic condition and produced 37.7 g/L of high optical purity L-lactate at 80 % of the maximum theoretical value. The result shown in this study implies that algal biomass would be as competitive with lignocellulosic biomass in terms of lactic acid production and that brown seaweed can be used as a feedstock for the industrial production of other chemicals. PMID:24297185

Mazumdar, Suman; Bang, Junho; Oh, Min-Kyu

2014-02-01

374

Evaluation of nonionic adsorbent resins for removal of inhibitory compounds from corncob hydrolysate for ethanol fermentation.  

PubMed

The aim of this study was to investigate the effect of XAD4-column treatment on removal of several fermentation inhibitors from corncob hydrolysate (CH). From analysis using a model hydrolysate, more than 99% of 5-hydroxy-methyl furfural, furfural and vanillin were removed by this treatment, and more than 97% of the total xylose, glucose and arabinose remained in the detoxified CH (DCH). The resulting DCH was tested as a substrate for ethanol production by Saccharomyces cerevisiae and Pichia stipitis. The highest ethanol levels for S. cerevisiae were 1.40 and 4.92 g l(-1) in CH and DCH, respectively. For P. stipitis, the levels were 0 and 4.73 g l(-1) in the CH and DCH media, respectively. The levels of alcohol volumetric productivity in the DCH medium were 0.374 and 0.200 g l(-1)h(-1) for S. cerevisiae and P. stipitis, respectively. PMID:24094738

Hatano, Ken-ichi; Aoyagi, Naokazu; Miyakawa, Takuya; Tanokura, Masaru; Kubota, Kenji

2013-12-01

375

Antihypertensive effect of enzymatic hydrolysate of collagen and Gly-Pro in spontaneously hypertensive rats.  

PubMed

Continuous oral feeding of enzymatic hydrolysate of porcine skin collagen showed an antihypertensive effect in spontaneously hypertensive rats (SHRs). We isolated an angiotensin I-converting enzyme (ACE) inhibitory peptide, Gly-Phe-Hyp-Gly-Pro (IC(50)=91 microM), from the hydrolysate, but the ACE inhibitory activities of the other peptides isolated were weak. Although the ACE inhibitory activity of Gly-Pro (IC(50)=360 microM) was not potent, Gly-Pro exists in collagen as a large number of repeated sequences. We then examined the antihypertensive effect of Gly-Pro. Orally administered Gly-Pro at 500 mg/kg significantly decreased the blood pressure of SHRs, and at 50 mg/kg it also showed a tendency to lower the blood pressure. Oral administration of Gly-Phe-Hyp-Gly-Pro (10 or 30 mg/kg) also decreased the blood pressure of SHRs. PMID:19809172

Ichimura, Toshiaki; Yamanaka, Akiko; Otsuka, Tatsuro; Yamashita, Eiichi; Maruyama, Susumu

2009-10-01

376

Bioflocculants from hydrolysates of corn stover using isolated strain Ochrobactium ciceri W2.  

PubMed

This study isolated a total of seven pure cultures from activated sludge that could produce bioflocculants from 1.7% v/v H2SO4 treated hydrolysates of corn stover. The most effective strain amongst the seven isolates was identified as Ochrobactrum ciceri W2. The W2 cells produced biopolymers in logarithm growth phase, peaking at 3.8 g l(-1)in productivity on 16 h. The yielded bioflocculant was primarily consisting of polysaccharides and proteins, and maintained its flocculating activity to 0.5% w/w kaolin suspensions over pH 1-10 (at 30°C) and 30-100°C (at pH 7). This study also revealed that the strain W2 could utilize biopolymers from hydrolysate of corn stover without addition of excess phosphate salts, which could largely reduce production costs of bioflocculants. PMID:23232033

Wang, Li; Ma, Fang; Lee, Duu-Jong; Wang, Aijie; Ren, Nanqi

2013-10-01

377

Kinetics of ethanol production from sugarcane bagasse enzymatic hydrolysate concentrated with molasses under cell recycle.  

PubMed

In this work, a kinetic model for ethanol fermentation from sugarcane bagasse enzymatic hydrolysate concentrated with molasses was developed. A model previously developed for fermentation of pure molasses was modified by the inclusion of a new term for acetic acid inhibition on microorganism growth rate and the kinetic parameters were estimated as functions of temperature. The influence of the hydrolysate on the kinetic parameters is analyzed by comparing with the parameters from fermentation of pure molasses. The impact of cells recycling in the kinetic parameters is also evaluated, as well as on the ethanol yield and productivity. The model developed described accurately most of the fermentations performed in several successive batches for temperatures from 30 to 38°C. PMID:23313680

de Andrade, Rafael Ramos; Maugeri Filho, Francisco; Maciel Filho, Rubens; da Costa, Aline Carvalho

2013-02-01

378

Maximizing the xylitol production from sugar cane bagasse hydrolysate by controlling the aeration rate.  

PubMed

Batch fermentations of sugar cane bagasse hemicellulosic hydrolysate treated for removing the inhibitors of the fermentation were performed by Candida guilliermondii FTI20037 for xylitol production. The fermentative parameters agitation and aeration rate were studied aiming the maximization of xylitol production from this agroindustrial residue. The maximal xylitol volumetric productivity (0.87 g/L h) and yield (0.67 g/g) were attained at 400/min and 0.45 v.v.m. (K(L)a 27/h). According to the results, a suitable control of the oxygen input permitting the xylitol formation from sugar cane bagasse hydrolysate is required for the development of an efficient fermentation process for large-scale applications. PMID:18576110

Silva, S S; Ribeiro, J D; Felipe, M G; Vitolo, M

1997-01-01

379

Reintroduced solids increase inhibitor levels in a pretreated corn stover hydrolysate.  

PubMed

Following detoxification of the liquid hydrolysate produced in a corn stover pretreatment process, inhibitor levels are seen to increase with the re-addition of solids for the ensuing hydrolysis and fermentation processes. The solids that were separated from the slurry before detoxification of the liquor contain approx 60% (w/w) moisture, and contamination occurs owing to the diffusion of inhibitors from the moisture entrained in the porous structure of the corn stover solids into the bulk fluid. This evidence suggests the need for additional separation and detoxification steps to purge residual inhibitors entrained in the moisture in the solids. An overliming process to remove furans from the hydrolysate failed to reduce total organic acids concentration, so acids were removed by treatment with an activated carbon powder. Smaller carbon doses proved more efficient in removing organic acids in terms of grams of acid removed per gram of carbon powder. Sugar adsorption by the activated carbon powder was minimal. PMID:16915673

Berson, R Eric; Young, John S; Hanley, Thomas R

2006-01-01

380

Quantification of hydroxyprolyl-glycine (Hyp-Gly) in human blood after ingestion of collagen hydrolysate.  

PubMed

Plasma levels of prolyl-hydroxyproline (Pro-Hyp) and hydroxyprolyl-glycine (Hyp-Gly) in healthy volunteers (n=5) after ingestion of collagen hydrolysate were estimated by liquid chromatography-tandem mass spectrometry. The ratio of Hyp-Gly to Pro-Hyp was distributed in the range of 0.063-0.221. This is a first report for quantification of food-derived Hyp-Gly in human plasma. PMID:22040651

Sugihara, Fumihito; Inoue, Naoki; Kuwamori, Masanori; Taniguchi, Makoto

2012-02-01

381

TOF SIMS and XPS study of the interaction of hydrolysed ?-aminopropyltriethoxysilane with E-glass surfaces  

Microsoft Academic Search

The interaction of E-glass surfaces with hydrolysed ?-aminopropyltriethoxysilane (HAPS) has been studied by time-of-flight secondary ion mass spectrometry (TOF SIMS) and X-ray photoelectron spectroscopy (XPS). The SIMS spectrum was found to consist of four series of fragmentation patterns, two of which could be assigned to the poly(aminosiloxane). The remaining two series were consistent with the well-known fragmentation of polydimethylsiloxane. Using

D. Wang; F. R. Jones; P. Denison

1992-01-01

382

Extreme thermophilic biohydrogen production from wheat straw hydrolysate using mixed culture fermentation: Effect of reactor configuration  

Microsoft Academic Search

Hydrogen production from hemicellulose-rich wheat straw hydrolysate was investigated in continuously-stirred tank reactor (CSTR), up-flow anaerobic sludge bed (UASB) reactor, and anaerobic filter (AF) reactor. The CSTR was operated at an hydraulic retention time (HRT) of 3days, and the UASB and AF reactors were operated at 1day HRT, using mixed extreme thermophiles at 70°C. The highest hydrogen production yield of

Prawit Kongjan; Irini Angelidaki

2010-01-01

383

Evaluation of xylitol production from corn cob hemicellulose hydrolysate by Candida parapsilosis  

Microsoft Academic Search

Candida parapsilosis was grown for 59 h in a medium containing corn cob hydrolysate consisting of 50 g xylose l-1, 3.0 g glucose l-1, 2.0 g arabinose l-1, and 0.9 g acetic acid l-1. A biomass of 9.1 g l-1 was produced with 36 g xylitol l-1 and 2.5 g ethanol l-1. In a medium containing 50 g xylose l-1 instead of corn cob

Sang-Yong Kim; Deok-Kun Oh; Jung-Hoe Kim

1999-01-01

384

Ethanol production using concentrated oak wood hydrolysates and methods to detoxify  

Microsoft Academic Search

Ethanol production from concentrated oak wood hydrolysate was carried out to obtain a high ethanol concentration and a high\\u000a ethanol yield. The effect of added inhibitory compounds, which are typically produced in the pretreatment step of steam-explosion\\u000a on ethanol fermentation, was also examined. p-Hydroxybenzoic aldehyde, a lignin-degradation product, was the most inhibitory compound tested in this study. Compounds with\\u000a additional

Woo Gi Lee; Jin Suk Lee; Chul Seung Shin; Soon Chul Park; Ho Nam Chang; Yong Keun Chang

1999-01-01

385

Isolation and assessment of phytate-hydrolysing bacteria from the DelMarVa Peninsula  

Microsoft Academic Search

Summary The Delaware-Maryland-Virginia (DelMarVa) Penin- sula, flanking one side of the Chesapeake Bay, is home to a substantial broiler chicken industry. As such, it produces a significant amount of manure that is typically composted and spread onto local crop- lands as a fertilizer. Phytate (myo inositol hexak- isphosphate), the major form of organic phosphorus in the manure, can be hydrolysed

Jane E. Hill; David Kysela; Menachem Elimelech

2007-01-01

386

DNA-hydrolysing activity of immunoglobulin G from bulk bovine colostrum  

Microsoft Academic Search

This paper represents the first report of DNA-hydrolysing activity of IgG fraction from bulk bovine colostrum. Ultrafiltration, Sephadex G-150 chromatography, protein G affinity chromatography and dialysis were used to obtain the IgG fraction, which was isolated and finally purified to homogeneity by SDS-PAGE. pBR322 DNA in the incubated mixture with the IgG fraction, which was subjected to electrophoresis in 0.8%

Jinsong Cao; Changhong Guo; Xiaoqin Wang; Chunyan He; Pingtai Zhang

2008-01-01

387

Kinetics of Enzyme Inhibition and Antihypertensive Effects of Hemp Seed ( Cannabis sativa L.) Protein Hydrolysates  

Microsoft Academic Search

The aim of this study was to determine the antihypertensive effects of enzymatic hemp seed protein hydrolysate (HPH) and its\\u000a peptide fractions. Hemp seed protein isolate was digested by the sequential action of pepsin and pancreatin to mimic gastrointestinal\\u000a digestion in human beings. The resultant HPH was separated by membrane ultrafiltration into peptide fractions with different\\u000a sizes (P < 0.05) in vitro

Abraham T. Girgih; Chibuike C. Udenigwe; Huan Li; Abayomi P. Adebiyi; Rotimi E. Aluko

388

Using photoactivated periodate to decompose TOC from hydrolysates of chemical warfare agents  

Microsoft Academic Search

Photoactivated periodate was investigated for the disposal of hydrolysates of chemical warfare agents (HCWAs) when hydrolysis is used as the first step in disposal of chemical warfare agents (CWAs). The kinetics and mechanisms of total organic carbon (TOC) loss by photoactivated periodate oxidation of the HCWAs, thiodiglycol (TDG), 3,3-dithiopropanol (TDP), and 1,4-thioxane (TX), were investigated at pH 3, 7, and

Xueming Tang; Linda K. Weavers

2008-01-01

389

Relationship between collagen hydrolysate molecular weight and peptide substantivity to hair  

Microsoft Academic Search

Synopsis Cosmetic grade collagen hydrolysates were incubated with virgin (natural) and bleached\\/waved (damaged) hair tresses. The bound collagen peptides were removed by both a high-temperature (50øC) and a high-salt (0.5 M NaCI) soak. As much as four times more fluorescamine reactive and hydroxyproline-containing peptides are removed from damaged than from natural hair. Gel filtration shows differences in the molec- ular

GILBERT R. MINTZ; GALE M. REINHART

390

Hemoglobin hydrolysates from porcine blood obtained through enzymatic hydrolysis assisted by high hydrostatic pressure processing  

Microsoft Academic Search

The purpose of this work was to obtain discoloured hemoglobin (Hb) hydrolysates from porcine red blood cells fraction by combining enzymatic hydrolysis and high hydrostatic pressure (HHP) treatments. Samples of Hb were submitted to treatments of enzymatic hydrolysis by trypsin (EC 3.4.21.4) or pepsin (EC 3.4.23.1), under controlled conditions of temperature and pH, for 2, 6 and 24h, and pressurization

M. Toldrà; D. Parés; E. Saguer; C. Carretero

2011-01-01

391

Chemical interactions between soil N and alkaline-hydrolysing N fertilizers  

Microsoft Academic Search

Chemical interactions between soil N and alkaline-hydrolysing N fertilizers labelled with15N were studied in the laboratory using twelve?-irradiated soils. Fertilizer was recovered in the soil organic N fraction via the process of NH3 fixation. NH3 fixation at day 7 varied from 1.8 to 4.6% of the N added as aqua ammonia at 1000 mg kg-1 soil. The amount of NH3

S. Sen; P. M. Chalk

1993-01-01

392

Determination of tryptophan by high-performance liquid chromatography of alkaline hydrolysates with spectrophotometric detection  

Microsoft Academic Search

A procedure for quantitation of tryptophan in feedstuff is described. It consist of hydrolysis in sodium hydroxide at 100 °C for 4 h, neutralization of the resulting hydrolysate to pH 7, dilution with sodium borate buffer (pH 9), and analysis by reverse-phase high-performance liquid chromatography with spectrophotometric determination of tryptophan at 280 nm. The recovery of tryptophan from lysozyme, added to

Mar??a M. Yust; Justo Pedroche; Julio Girón-Calle; Javier Vioque; Francisco Millán; Manuel Alaiz

2004-01-01

393

Quantitative Untersuchungen über die extracelluläre Hydrolyse von Kohlenhydraten durch Juniperus communis -Gewebekulturen  

Microsoft Academic Search

Zusammenfassung der Ergebnisse 1.Durch Gewebekulturen vonJuniperus communis werden neben Stärke und Saccharose auch Maltose und Raffinose extracellulär hydrolysiert.2.Bei der Hydrolyse der genannten Kohlenhydrate wird in jedem Fall die Monosaccharidstufe erreicht. Der Hexosenanteil an den Hydrolysaten ist beträchtlich.3.Glucose und Fructose sind im Hydrolysat von Saccharose am Ende einer Gewebepassage im Verhältnis 1:1 vorhanden.4.Durch Schnittverletzung der Gewebe vor der Beimpfung der Nährböden

Friedrich Constabel

1963-01-01

394

Plasticizing collagen hydrolysate with glycerol and low-molecular weight poly(ethylene glycols)  

Microsoft Academic Search

The plasticizing efficiency of glycerol (GLY)and poly(ethylene glycols) of molecular mass 300–3350Da (PEG 300–PEG 3350) for films of collagen hydrolysate (H) was assessed on the basis of the glass transition temperature depression (?Tg). The plasticizing effect of hydrophilic plasticizers was separated from the plasticizing effect of water absorbed to H films by means of two-stage differential scanning calorimetry (DSC). The

F. Langmaier; P. Mokrejs; K. Kolomaznik; M. Mladek

2008-01-01

395

Curing of urea-formaldehyde adhesives with collagen type hydrolysates under acid condition  

Microsoft Academic Search

Condensation of dimethylol urea and its mixtures with urea or hydrolysate of chrome-tanned leather waste (mass fraction in\\u000a mixture 0.05) in the presence of a variable quantity of phthalic acid, as acid curing agent (within mass fraction limits 0.01-0.1),\\u000a was studied through TG technique. During condensation of sole dimethylol urea or of its mixture with urea, oxy-methylene as\\u000a well as

F. Langmaier; J. Šivarová; K. Kolomazník; M. Mládek

2004-01-01

396

Heat-treated biodegradable films and foils of collagen hydrolysate crosslinked with dialdehyde starch  

Microsoft Academic Search

Gels of collagen hydrolysate (H) crosslinked with dialdehyde starch (DAS) are marked by a strong tendency to aging, which\\u000a means a certain problem during their processing into biodegradable packaging materials. Applying casting technology and drying\\u000a these materials by heating air-dry films and foils for a limited time (1–4 h) at 105 °C may eliminate the aging problem. Solubility\\u000a of heat-treated films

F. Langmaier; P. Mokrejs; M. Mladek

2010-01-01

397

Biodegradable packing materials based on waste collagen hydrolysate cured with dialdehyde starch  

Microsoft Academic Search

Hydrogels of collagen hydrolysate (H) of mean M\\u000a w 15–30 kDa obtained from waste collagen from meat casings manufacture, cross-linked with 15% (based on H) polymeric dialdehyde\\u000a starch (DAS), have a marked tendency to ageing, which shows in hydrogel gradually increasing rigidity and decreasing thermo-reversibility.\\u000a Methods of thermal analysis (DSC, TG) proved that ageing of hydrogels is not related with

F. Langmaier; M. Mládek; P. Mokrejš; K. Kolomazník

2008-01-01

398

Study on effect of jellyfish collagen hydrolysate on anti-fatigue and anti-oxidation  

Microsoft Academic Search

Many bioactive peptides possess specific biological properties that make potential ingredients of health-promoting foods. Jellyfish, which is rich in collagen, has high nutritious and medicinal value. In this study, jellyfish collagen hydrolysate (JCH) were produced. The in vivo anti-fatigue activity and in vivo antioxidant activity of JCH were determined, respectively. Climbing endurance tests of mice were carried out after 6w

Jin-Feng Ding; Yan-Yan Li; Jia-Jie Xu; Xiu-Rong Su; Xiang Gao; Fu-Peng Yue

2011-01-01

399

Protein Hydrolysates Are Avoided by Herbivores but Not by Omnivores in Two-Choice Preference Tests  

Microsoft Academic Search

BackgroundThe negative sensory properties of casein hydrolysates (HC) often limit their usage in products intended for human consumption, despite HC being nutritious and having many functional benefits. Recent, but taxonomically limited, evidence suggests that other animals also avoid consuming HC when alternatives exist.Methodology\\/Principal FindingsWe evaluated ingestive responses of five herbivorous species (guinea pig, mountain beaver, gopher, vole, and rabbit) and

Kristin L. Field; Alexander A. Bachmanov; Julie A. Mennella; Gary K. Beauchamp; Bruce A. Kimball; Daniel Tomé

2009-01-01

400

Curing adhesives of urea-formaldehyde type with collagen hydrolysates of chrome-tanned leather waste  

Microsoft Academic Search

Condensation of dimethylol-urea (DMU) mixed with urea (U) and collagen hydrolysate (H), obtained through enzymatic hydrolysis of chrome-tanned leather waste, without added acid curing agents in the solid phase was studied through DSC and TG techniques in a temperature interval up to 220°C. Among both techniques TG proved be more useful.While the DMU+U mix produced methylene-oxide (-CH2-O-CH2-) and methylene (-CH2-)

F. Langmaier; J. Šivarová; M. Mládek; K. Kolomazník

2004-01-01

401

Cross-linking epoxide resins with hydrolysates of chrome-tanned leather waste  

Microsoft Academic Search

Differential scanning calorimetry was employed to investigate the reaction of diglycidyl ethers of bisphenol A (DGEBA) of\\u000a mean molecular mass 348–480 Da, with collagen hydrolysate of chrome-tanned leather waste in a solvent-free environment. The\\u000a reaction leads to biodegradable polymers that might facilitate recycling of plastic parts in products of the automotive and\\/or\\u000a aeronautics industry provided with protective films on this

F. Langmaier; P. Mokrejs; K. Kolomazník; M. Mládek; R. Karnas

2007-01-01

402

Quantification of hydroxyprolyl-glycine (Hyp-Gly) in human blood after ingestion of collagen hydrolysate  

Microsoft Academic Search

Plasma levels of prolyl-hydroxyproline (Pro-Hyp) and hydroxyprolyl-glycine (Hyp-Gly) in healthy volunteers (n=5) after ingestion of collagen hydrolysate were estimated by liquid chromatography–tandem mass spectrometry. The ratio of Hyp-Gly to Pro-Hyp was distributed in the range of 0.063–0.221. This is a first report for quantification of food-derived Hyp-Gly in human plasma.

Fumihito Sugihara; Naoki Inoue; Masanori Kuwamori; Makoto Taniguchi

403

Comparative ethanol productivities of different Zymomonas recombinants fermenting oat hull hydrolysate  

Microsoft Academic Search

Iogen Corporation of Ottawa, Canada, has recently built a 50 t\\/d biomass-to-ethanol demonstration plant adjacent to its enzyme\\u000a production facility. Iogen has partnered with the University of Toronto to test the C6\\/C5 cofermentation performance characteristics\\u000a of National Renewable Energy Laboratory's metabolically engineered Zymomonas mobilis using its biomass hydrolysates. In this study, the biomass feedstock was an agricultural waste, namely oat

Hugh G. Lawford; Joyce D. Rousseau; Jeffrey S. Tolan

2001-01-01

404

Alginate fibres modified with unhydrolysed and hydrolysed chitosans for wound dressings  

Microsoft Academic Search

A range of commercial chitosans were sourced, subjected to controlled acid hydrolysis, and their molecular size profiles and degrees of acetylation (DA) determined (pre- and post-hydrolysis) by High Performance Size Exclusion Chromatography and 1H-NMR spectroscopy, respectively. Unhydrolysed and hydrolysed chitosans were subsequently utilised for modification of sodium alginate\\/alginic acid fibres (prepared using a range of different fibre spinning conditions), and

C. J Knill; J. F Kennedy; J Mistry; M Miraftab; G Smart; M. R Groocock; H. J Williams

2004-01-01

405

Preparation of hydrolysates from bovine red blood cells and their debittering following plastein reaction  

Microsoft Academic Search

Protein hydrolysates from bovine red blood cells were prepared using commercially available Alcalase. The best nitrogen recovery (69.2%) was achieved at a degree of hydrolysis (DH) of 25%. However, the product so obtained had a strong bitter taste (4.3 on a 5-point scale). At DH 16%, the nitrogen recovery was 65.9% and the bitter taste of product decreased (to 3.5).

J. Synowiecki; R. Jagietka; F. Shahidi

1996-01-01

406

[Effect of byproducts in lignocellulose hydrolysates on ethanol fermentation by Issatchenkia orientalis].  

PubMed

Byproducts in lignocellulose hydrolysates, namely sodium formate (1 to 5 g/L), sodium acetic (2.5 to 8.0 g/L), furfural (0.2-2 g/L), 5-hydroxymethylfurfural (5-HMF, 1 to 1.0 g/L) or vanillin (0.5 to 2 g/L) were used to evaluate their effects on ethanol fermentation by Issatchenkia orientalis HN-1 using single factor test and the response surface central composite experiment. Results showed that most of the byproducts had no obvious inhibition on the production of ethanol, except for the addition of 2 g/L vanillin or 1 g/L of 5-HMF, which reduced the ethanol production by 20.38% and 11.2%, respectively. However, high concentration of some byproducts in lignocellulose hydrolysates, such as sodium formate (1 to 5 g/L), sodium acetic (2.5 to 8.0 g/L), furfural (0.2 to 2 g/L) and vanillin (0.5 to 2 g/L) inhibited the growth of I. orientalis HN-1 significantly. Compared with the control, the dry cell weight of I. orientalis HN-1 decreased by 25.04% to 37.02%, 28.83% to 43.82%, 20.06% to 37.60% and 26.39% to 52.64%, respectively, when the above components were added into the fermentation broth and the fermentation lasted for 36 h. No significant interaction effect of the various inhibitors (sodium formate, sodium acetic, furfural and vanillin) except for vanillin single factor on the ethanol production was observed based on the central composite experiments. The concentrations of byproducts in most lignocellulose hydrolysates were below the initial inhibition concentration on ethanol production by Issatchenkia orientalis HN-1, which indicated that Issatchenkia orientalis HN-1 can be used for ethanol production from lignocellulose hydrolysates. PMID:25118399

Wang, Fengqin; Liu, Yaqiong; Zhang, Rui; Wang, Yuanyuan; Xie, Hui; Song, Andong

2014-05-01

407

Storage of Brewing Yeasts by Liquid Nitrogen Refrigeration  

PubMed Central

Many yeast strains are difficult to maintain in culture in a stable state, and long-term preservation by lyophilization, which has proved useful for other fungi, has given poor results with brewing yeasts. As an alternative to continuous subculture, which maximizes strain variability, various methods of cryogenic storage were investigated. Yeast strains were frozen with or without cryoprotectants (such as glycerol or inositol) and stored at -196 C. Recovery after warming was estimated from plate counts, and survivors were screened to detect changes in the frequency of morphological types, respiratory-deficient mutants, and glycerol-sensitive mutants. Strains varied in their sensitivity to freezing, and survival was modified by the growth medium, the freezing munstrua, and the freezing conditions. Suspension of cells in 10% (vol/vol) glycerol, cooled at 1 C/min, warmed rapidly and plated on malt-yeast extract-glucose-peptone agar produced the highest percentage of viable colonies with a minimal change in metabolic characteristics. In two of the strains tested, no significant increase in mutation rate was detected under any of the treatments; the strains were maintained in a stable state and were metabolically comparable to unfrozen strains. In one strain of Saccharomyces uvarum after some freezing treatments, the percentage of respiratory-deficient mutants increased markedly, the fermentation rate declined, and a loss of flocculation occurred. The freezing parameters which increased the level of respiratory-deficient cells should be avoided in maintaining this strain. Maintenance of cultures of brewing yeasts by cryogenic storage has several advantages over other preservation techniques: the method is simple and reproducible, the cultures have remained stable over a 3-year test period, and the viability is high. PMID:16349973

Wellman, A. M.; Stewart, G. G.

1973-01-01

408

Transcriptomic and peptidomic analysis of protein hydrolysates from the white shrimp (L. vannamei).  

PubMed

An RNAseq approach associated to mass spectrometry was conducted to assess the composition, molecular mass distribution and primary sequence of hydrolytic peptides issued from hydrolysates of white shrimp (Litopenaeus vannamei) by-products. High performance size exclusion chromatography (HPSEC) analyses indicated that 69.2% of the 214-nm-absorbing components had apparent molecular masses below 1000Da, and 88.3% below 2000Da. OFFGEL-nLC-MALDI-TOF/TOF and nLC-ESI-MS/MS analyses led to the identification of 808 peptides based on the NCBI EST databank (161,397 entries) completed by the new L. vannamei databank (58,508 entries) that we created from the RNAs of tissues used for hydrolysate production. Whereas most of hydrolytic peptides have a MW below 2000Da, preliminary investigations of antimicrobial properties revealed three antibacterial fractions that demonstrate functional activities. The abundance of small peptides as well as the biological activities detected could imply very interesting applications for shrimp hydrolysate in the field of aquaculture feeding. PMID:24998765

Robert, Marie; Zatylny-Gaudin, Céline; Fournier, Vincent; Corre, Erwan; Le Corguillé, Gildas; Bernay, Benoît; Henry, Joël

2014-09-30

409

Study of antioxidant activity of sheep visceral protein hydrolysate: Optimization using response surface methodology  

PubMed Central

BACKGROUND The main objective of this experiment was optimal use of none edible protein source to increase nutritional value of production with high biological function, including antioxidant activity. METHODS Sheep visceral (stomach and intestine) was used as substrate. Response surface methodology (RSM) was used to optimize hydrolysis conditions for preparing protein hydrolysate from the sheep visceral, using alcalase 2.4 l enzyme. The investigated factors were temperature (43-52 °C), time (90-180 min), and enzyme/substrate ratio [60-90 Anson-unit (AU)/kg protein] to achieve maximum antioxidant activity. Experiments were designed according to the central composite design. RESULTS Each of the studied variables had a significant effect on responses (P < 0.05). Optimal conditions to achieve antioxidant activity were, temperature (48.27 °C), time (158.78), min and enzyme/substrate ratio (83.35) Anson-unit/kg protein. Under these conditions, antioxidant activity was 68.21%, R2 for model was 0.983. The values indicated the high accuracy of the model to predict the reaction conditions considering different variables. The chemical analysis of protein hydrolysate showed high protein content (83.78%) and low fat content (0.34%). CONCLUSION Our results showed that protein hydrolysate of sheep visceral, can be used as a natural antioxidant with high nutritional value. PMID:25258632

Meshginfar, Nasim; Sadeghi-Mahoonak, Alireza; Ziaiifar, Aman Mohammad; Ghorbani, Mohammad; Kashaninejad, Mahdi

2014-01-01

410

Polyhydroxyalkanoate biosynthesis and simultaneous remotion of organic inhibitors from sugarcane bagasse hydrolysate by Burkholderia sp.  

PubMed

Burkholderia sp. F24, originally isolated from soil, was capable of growth on xylose and removed organic inhibitors present in a hemicellulosic hydrolysate and simultaneously produced poly-3-hydroxybutyrate (P3HB). Using non-detoxified hydrolysate, Burkholderia sp. F24 reached a cell dry weight (CDW) of 6.8 g L(-1), containing 48 % of P3HB and exhibited a volumetric productivity (PP3HB) of 0.10 g L(-1) h(-1). Poly-3-hydroxybutyrate-co-3-hydroxyvalerate copolymers (P3HB-co-3HV) were produced using xylose and levulinic acid (LA) as carbon sources. In shake flask cultures, the 3HV content in the copolymer increased from 9 to 43 mol% by adding LA from 1.0 to 5.0 g L(-1). In high cell density cultivation using concentrated hemicellulosic hydrolysate F24 reached 25.04 g L(-1) of CDW containing 49 % of P3HB and PP3HB of 0.28 g L(-1 )h(-1). Based on these findings, second-generation ethanol and bioplastics from sugarcane bagasse is proposed. PMID:25059637

Lopes, Mateus Schreiner Garcez; Gomez, José Gregório Cabrera; Taciro, Marilda Keico; Mendonça, Thatiane Teixeira; Silva, Luiziana Ferreira

2014-09-01

411

Optimization of the Preparation of Fish Protein Anti-Obesity Hydrolysates Using Response Surface Methodology  

PubMed Central

The enzymatic condition for producing the anti-obesity hydrolysates from fish water-soluble protein was optimized with the aid of response surface methodology, which also derived a statistical model for experimental validation. Compared with neutral protease, papain and protamex, the porcine pancreas lipase inhibitory rate of hydrolysates from fish water-soluble protein was higher with alkaline protease. Results showed that the model terms were significant, the terms of lack of fit were not significant, and the optimal conditions for the hydrolysis by alkaline protease were initial pH 11, temperature 39 °C, enzyme dosage 122 U/mL and 10 h of hydrolysis time. Under these conditions, the porcine pancreas lipase and the ?-amylase inhibitory rate could reach 53.04% ± 1.32% and 20.03 ± 0.89%, while predicted value were 54.63% ± 1.75%, 21.22% ± 0.70%, respectively. In addition, Lineweaver-Burk plots showed noncompetitive inhibition. The Ki value calculated was 84.13 mg/mL. These results demonstrated that fish water-soluble protein could be used for obtaining anti-obesity hydrolysates. PMID:23377020

Liu, Liyuan; Wang, Yanping; Peng, Chen; Wang, Jinju

2013-01-01

412

Enhanced xylitol production by precultivation of Candida guilliermondii cells in sugarcane bagasse hemicellulosic hydrolysate.  

PubMed

The present work evaluated the key enzymes involved in xylitol production (xylose reductase [XR] and xylitol dehydrogenase [XDH]) and their correlation with xylose, arabinose, and acetic acid assimilation during cultivation of Candida guilliermondii FTI 20037 cells in sugarcane bagasse hemicellulosic hydrolysate. For this purpose, inocula previously grown either in sugarcane bagasse hemicellulosic hydrolysate (SBHH) or in semidefined medium (xylose as a substrate) were used. The highest xylose/acetic acid consumption ratio (1.78) and the lowest arabinose consumption (13%) were attained in the fermentation using inoculum previously grown in semidefined medium (without acetic acid and arabinose). In this case, the highest values of XR (1.37 U mg prot(-1)) and XDH (0.91 U mg prot(-1)) activities were observed. The highest xylitol yield (approximately 0.55 g g(-1)) and byproducts (ethanol and glycerol) formation were not influenced by inoculum procedure. However, the cell previously grown in the hydrolysate was effective in enhancing xylitol production by keeping the XR enzyme activity at high levels (around 0.99 U.mg(prot) (-1)), reducing the XDH activity (34.0%) and increasing xylitol volumetric productivity (26.5%) with respect to the inoculum cultivated in semidefined medium. Therefore, inoculum adaptation to SBHH was shown to be an important strategy to improve xylitol productivity. PMID:16775788

Rodrigues, Rita C L B; Sene, Luciane; Matos, Gilvane S; Roberto, Inês C; Pessoa, Adalberto; Felipe, Maria G A

2006-07-01

413

Observations on the Yeast Lipomyces  

Microsoft Academic Search

IN 1946, Starkey1 isolated and described a soil yeast characterized by a peculiar method of spore formation after a relatively long period of growth on solid medium. Large, round vegetative cells containing fat globules gave rise to irregularly shaped protuberances in which were afterwards formed 4-16 or more lightly pigmented spores. Lodder and Kregervan Rij2 considered these spores to be

Catherine Roberts

1957-01-01

414

Fermentation of levoglucosan with oleaginous yeasts for lipid production.  

PubMed

This paper reports the production of lipids from non-hydrolyzed levoglucosan (LG) by oleaginous yeasts Rhodosporidium toruloides and Rhodotorula glutinis. Enzyme activity tests of LG kinases from both yeasts indicated that the phosphorylation pathway of LG to glucose-6-phosphate existed. The highest enzyme activity obtained for R. glutinis was 0.22 U/mg of protein. The highest cell mass and lipid production by R. glutinis were 6.8 and 2.7 g/L, respectively from pure LG, and 3.3 and 0.78 g/L from a pyrolytic LG aqueous phase detoxified by ethyl acetate extraction, rotary evaporation and activated carbon. This corresponded to a lipid yield of 13.5 wt.% for pure LG and only 3.9 wt.% for LG in pyrolysis oil. PMID:23425586

Lian, Jieni; Garcia-Perez, Manuel; Chen, Shulin

2013-04-01

415

Saccharomyces Genome Database: the genomics resource of budding yeast.  

PubMed

The Saccharomyces Genome Database (SGD, http://www.yeastgenome.org) is the community resource for the budding yeast Saccharomyces cerevisiae. The SGD project provides the highest-quality manually curated information from peer-reviewed literature. The experimental results reported in the literature are extracted and integrated within a well-developed database. These data are combined with quality high-throughput results and provided through Locus Summary pages, a powerful query engine and rich genome browser. The acquisition, integration and retrieval of these data allow SGD to facilitate experimental design and analysis by providing an encyclopedia of the yeast genome, its chromosomal features, their functions and interactions. Public access to these data is provided to researchers and educators via web pages designed for optimal ease of use. PMID:22110037

Cherry, J Michael; Hong, Eurie L; Amundsen, Craig; Balakrishnan, Rama; Binkley, Gail; Chan, Esther T; Christie, Karen R; Costanzo, Maria C; Dwight, Selina S; Engel, Stacia R; Fisk, Dianna G; Hirschman, Jodi E; Hitz, Benjamin C; Karra, Kalpana; Krieger, Cynthia J; Miyasato, Stuart R; Nash, Rob S; Park, Julie; Skrzypek, Marek S; Simison, Matt; Weng, Shuai; Wong, Edith D

2012-01-01

416

Saccharomyces Genome Database: the genomics resource of budding yeast  

PubMed Central

The Saccharomyces Genome Database (SGD, http://www.yeastgenome.org) is the community resource for the budding yeast Saccharomyces cerevisiae. The SGD project provides the highest-quality manually curated information from peer-reviewed literature. The experimental results reported in the literature are extracted and integrated within a well-developed database. These data are combined with quality high-throughput results and provided through Locus Summary pages, a powerful query engine and rich genome browser. The acquisition, integration and retrieval of these data allow SGD to facilitate experimental design and analysis by providing an encyclopedia of the yeast genome, its chromosomal features, their functions and interactions. Public access to these data is provided to researchers and educators via web pages designed for optimal ease of use. PMID:22110037

Cherry, J. Michael; Hong, Eurie L.; Amundsen, Craig; Balakrishnan, Rama; Binkley, Gail; Chan, Esther T.; Christie, Karen R.; Costanzo, Maria C.; Dwight, Selina S.; Engel, Stacia R.; Fisk, Dianna G.; Hirschman, Jodi E.; Hitz, Benjamin C.; Karra, Kalpana; Krieger, Cynthia J.; Miyasato, Stuart R.; Nash, Rob S.; Park, Julie; Skrzypek, Marek S.; Simison, Matt; Weng, Shuai; Wong, Edith D.

2012-01-01

417

Producing aglycons of ginsenosides in bakers' yeast  

PubMed Central

Ginsenosides are the primary bioactive components of ginseng, which is a popular medicinal plant that exhibits diverse pharmacological activities. Protopanaxadiol, protopanaxatriol and oleanolic acid are three basic aglycons of ginsenosides. Producing aglycons of ginsenosides in Saccharomyces cerevisiae was realized in this work and provides an alternative route compared to traditional extraction methods. Synthetic pathways of these three aglycons were constructed in S. cerevisiae by introducing ?-amyrin synthase, oleanolic acid synthase, dammarenediol-II synthase, protopanaxadiol synthase, protopanaxatriol synthase and NADPH-cytochrome P450 reductase from different plants. In addition, a truncated 3-hydroxy-3-methylglutaryl-CoA reductase, squalene synthase and 2,3-oxidosqualene synthase genes were overexpressed to increase the precursor supply for improving aglycon production. Strain GY-1 was obtained, which produced 17.2?mg/L protopanaxadiol, 15.9?mg/L protopanaxatriol and 21.4?mg/L oleanolic acid. The yeast strains engineered in this work can serve as the basis for creating an alternative way for producing ginsenosides in place of extractions from plant sources. PMID:24424342

Dai, Zhubo; Wang, Beibei; Liu, Yi; Shi, Mingyu; Wang, Dong; Zhang, Xianan; Liu, Tao; Huang, Luqi; Zhang, Xueli

2014-01-01

418

Genetically modified industrial yeast ready for application.  

PubMed

Tremendous progress in the genetic engineering of yeast had been achieved at the end of 20th century, including the complete genome sequence, genome-wide gene expression profiling, and whole gene disruption strains. Nevertheless, genetically modified (GM) baking, brewing, wine, and sake yeasts have not, as yet, been used commercially, although numerous industrial recombinant yeasts have been constructed. The recent progress of genetic engineering for the construction of GM yeast is reviewed and possible requirements for their application are discussed. 'Self-cloning' yeast will be the most likely candidate for the first commercial application of GM microorganisms in food and beverage industries. PMID:16233347

Akada, Rinji

2002-01-01

419

Short-term temporal dynamics of yeast abundance on the tall fescue phylloplane.  

PubMed

Six replicate trials were conducted to determine the short-term temporal dynamics and the effects of foliar applications of nutrients on the phylloplane yeast community of tall fescue (Festuca arundinacea Schreb.). In each trial, 2% sucrose + 0.5% yeast extract solution or sterile deionized water (control) was applied to the experiment plots. Twelve hours post-treatment (at 0600 hours), leaf samples were collected and yeast colony-forming units (cfu) were enumerated by dilution plating. This process was repeated at 1200, 1800, and 2400 hours in each trial. Significant differences were observed between the number of yeast cfu and the time at which the samples were collected. On average, the number of yeast cfu recovered was significantly less at 1800 hours and significantly greatest at 2400 hours when compared with all other sampling times. Averaged over all time intervals, we observed a trend of increased yeast abundance in turf treated with the nutrient solution compared with control treatments. In a separate investigation, atmospheric yeast abundance above the canopy of tall fescue was assessed in the morning (0900) and in the afternoon (1500) using a Thermo Andersen single stage viable particle sampler. In 5 of the 6 trials of this experiment, atmospheric yeast abundance was significantly greater in the morning than in the afternoon. Results suggest the following colonization model: phylloplane yeasts on tall fescue reproduce during the late evening and early morning, stabilize during the late morning and early afternoon through exchange of immigrants and emigrants, and decline during the late afternoon and (or) early evening. PMID:18389002

Nix, Shannon S; Burpee, Leon L; Jackson, Kimberly L; Buck, James W

2008-04-01

420

Production of cellulosic ethanol and enzyme from waste fiber sludge using SSF, recycling of hydrolytic enzymes and yeast, and recombinant cellulase-producing Aspergillus niger.  

PubMed

Bioethanol and enzymes were produced from fiber sludges through sequential microbial cultivations. After a first simultaneous saccharification and fermentation (SSF) with yeast, the bioethanol concentrations of sulfate and sulfite fiber sludges were 45.6 and 64.7 g/L, respectively. The second SSF, which included fresh fiber sludges and recycled yeast and enzymes from the first SSF, resulted in ethanol concentrations of 38.3 g/L for sulfate fiber sludge and 24.4 g/L for sulfite fiber sludge. Aspergillus niger carrying the endoglucanase-encoding Cel7B gene of Trichoderma reesei was grown in the spent fiber sludge hydrolysates. The cellulase activities obtained with spent hydrolysates of sulfate and sulfite fiber sludges were 2,700 and 2,900 nkat/mL, respectively. The high cellulase activities produced by using stillage and the significant ethanol concentrations produced in the second SSF suggest that onsite enzyme production and recycling of enzyme are realistic concepts that warrant further attention. PMID:24862324

Cavka, Adnan; Alriksson, Björn; Rose, Shaunita H; van Zyl, Willem H; Jönsson, Leif J

2014-08-01

421

Antimicrobial activity of Wedelia trilobata crude extracts.  

PubMed

A biological screening of activity against Gram-positive and Gram-negative bacteria, yeasts, and fungi of crude extracts from Wedelia trilobata is reported. The n-hexane extract showed antibacterial activity against Bacillus subtilis, Mycobacterium smegmatis, Staphylococcus aureus, and Staphylococcus epidermidis (Gram-positive bacteria); along with Proteus vulgaris, Pseudomonas aeruginosa, Salmonella group C, Salmonella paratyphi, and Shigella sonnei (Gram-negative bacteria). The ethyl acetate extract was active only against Salmonella group C; and the aqueous extract was inactive against the tested bacteria. None of the tested extracts showed biological activity against the yeasts (Candida albicans, Candida tropicalis, Rhodotorula rubra) or the fungi (Aspergillus flavus, Aspergillus niger, Mucor sp., Trichophyton rubrum). PMID:10374253

Taddei, A; Rosas-Romero, A J

1999-05-01

422

Comparison of antioxidant activities of onion and garlic extracts by inhibition of lipid peroxidation and radical scavenging activity  

Microsoft Academic Search

The antioxidant activities of the methanol extracts of selected varieties and parts of garlic and onion were determined by two methods: inhibition of lipid peroxidation induced by tert-butyl hydroperoxide in isolated rat hepatocytes and scavenging activity against diphenylpicrylhydrazyl radical. The total phenolics and the main flavonoids of the hydrolysed onion and garlic samples were also analysed. The antioxidant activities obtained

Anna Maria Nuutila; Riitta Puupponen-Pimiä; Marjukka Aarni; Kirsi-Marja Oksman-Caldentey

2003-01-01

423

A yeast isolated from cashew apple juice and its ability to produce first- and second-generation ethanol.  

PubMed

The aim of this study was to isolate and identify an indigenous yeast from cashew apple juice (CAJ) and then use it in the production of first- and second-generation ethanol, using CAJ and the enzymatic hydrolysate of cashew apple bagasse (MCAB-OH), respectively. The isolated yeast was identified as belonging to the genus Hanseniaspora. Afterward, the effect of the medium initial pH on the production of ethanol from CAJ was evaluated in the range of 3.0 to 5.5, with its maximum ethanol production of 42 g L(-1) and Y P/S of 0.44 g g(-1) and 96 % efficiency. The effect of temperature (28-38 °C) on ethanol production was evaluated in a synthetic medium, and no difference in ethanol production in the temperature range evaluated (28-36 °C) was observed. At 32 °C, the yield, concentration, efficiency, and productivity of ethanol when using the CAJ medium were higher when compared to the results achieved for the synthetic medium. Regarding second-generation ethanol, the results showed that the yeast produced 24.37 g L(-1) of ethanol with an efficiency of 80.23 % and a productivity of 4.87 g L(-1) h(-1) at 5 h. Therefore, Hanseniaspora sp., isolated from CAJ, is a promising microorganism for the production of first- and second-generation ethanol. PMID:25238918

Barros, E M; Rodrigues, T H S; Pinheiro, A D T; Angelim, A L; Melo, V M M; Rocha, M V P; Gonçalves, Luciana R B

2014-12-01

424

Evaluation of Composition and Antimicrobial Activity of Supercritical Fluid Extract of Leaves of Vitex negundo  

PubMed Central

Supercritical fluid extract of leaves of Vitex negundo was tested for its antimicrobial potential and was compared with that of ethanol extract, ether extract and hydrodistilled oil of leaves. The chemical constituents of extracts were studied by chromatographic techniques. Extracts were evaluated for antimicrobial potential against bacterial strains like Staphylococcus aureus, Bacillus subtilis, Escherichia coli, Pseudomonas aeruginosa and yeast Candida albicans. Extracts showed prominent antibacterial activity against Bacillus subtilis and Staphylococcus aureus. Supercritical fluid extract exhibited good antibacterial potential. PMID:21695000

Nagarsekar, K. S.; Nagarsenker, M. S.; Kulkarni, S. R.

2010-01-01

425

Rapid identification of bioactive peptides with antioxidant activity from the enzymatic hydrolysate of Mactra veneriformis by UHPLC-Q-TOF mass spectrometry.  

PubMed

Analysis of peptide components of protein hydrolysates is often difficult due to the lack of suitable analytical methods. In the present study, an UHPLC-Q-TOF MS/MS method was developed and used to identify peptides derived from the protein hydrolysate of Mactra veneriformis. The peptide sequences were deduced by de novo sequencing based on MS/MS fragmentation data. A total of 21 peptides, four nucleobases, and one nucleoside were identified from the hydrolysate using this method. These peptides were chemically synthesised and showed antioxidant activity in radical scavenging assays. This method is suitable for quick, sensitive, and accurate analysis of complex protein hydrolysates. PMID:25149015

Liu, Rui; Zheng, Wenwen; Li, Jun; Wang, Lingchong; Wu, Hao; Wang, Xinzhi; Shi, Lei

2015-01-15

426

Screening of yeasts for cell-free production of ( R )-phenylacetylcarbinol  

Microsoft Academic Search

105 yeast strains from 10 genera and 40 species were evaluated for cell-free production of (R)-phenylacetylcarbinol (PAC), the chiral precursor in the manufacture of the pharmaceuticals ephedrine and pseudoephedrine. Carboligase activity of pyruvate decarboxylase (PDC), forming PAC from benzaldehyde and pyruvate, was found in extracts of 98 strains. PAC was not formed from benzaldehyde and acetaldehyde, an activity of bacterial

Bettina Rosche; Michael Breuer; Bernhard Hauer; Peter L. Rogers

2003-01-01

427

Effects of Solid-State Yeast Treatment on the Antioxidant Properties and Protein and Fiber  

E-print Network

Effects of Solid-State Yeast Treatment on the Antioxidant Properties and Protein and Fiber, including extractable antioxidant properties, protein contents, and soluble and insoluble fiber compositions treatments were able to significantly increase releasable antioxidant properties ranging from 28 to 65, from

Liu, Jian-Guo

428

Validation of a Flour-Free Model Dough System for Throughput Studies of Baker's Yeast  

Microsoft Academic Search

Evaluation of gene expression in baker's yeast requires the extraction and collection of pure samples of RNA. However, in bread dough this task is difficult due to the complex composition of the system. We found that a liquid model system can be used to analyze the transcriptional response of industrial strains in dough with a high sugar content. The production

Joaquin Panadero; Francisca Randez-Gil; Jose Antonio Prieto

2005-01-01

429

A small-scale method for quantitation of carotenoids in bacteria and yeasts.  

PubMed

Microbial carotenoids are difficult to extract because of their embedding into a compact matrix and prominent sensitivity to degradation. Especially for carotenoid analysis of bacteria and yeasts, there is lack of information about capability, precision and recovery of the method used. Accordingly, we investigated feasibility, throughput and validity of a new small-scale method using Micrococcus luteus and Rhodotorula glutinis for testing purposes. For disintegration and extraction, we combined primarily mild techniques: enzymatically we used combinations of lysozyme and lipase for bacteria as well as lyticase and lipase for yeasts. Additional mechanical treatment included sonication and freeze-thawing cycles. Chemical treatment with dimethylsulfoxide was applied for yeasts only. For extraction we used a methanol-chloroform mixture stabilized efficiently with butylated hydroxytoluene and alpha-tocopherol. Separation of compounds was achieved with HPLC, applying a binary methanol/tert-butyl methyl ether gradient on a polymer reversed C30 phase. Substances of interest were detected and identified applying a photodiode-array (PDA) and carotenoids quantitated as all-trans-beta-carotene equivalents. For evaluation of recovery and reproducibility of the extraction method, we used beta-8'-apo-carotenal as internal standard. The method provides a sensitive tool for the determination of carotenoids from bacteria and yeasts and also for small changes in carotenoid spectrum of a single species. Corequisite large experiments are facilitated by the high throughput of the method. PMID:17509707

Kaiser, Philipp; Surmann, Peter; Vallentin, Gerald; Fuhrmann, Herbert

2007-07-01

430

Production of bacterial cellulose by Gluconacetobacter hansenii CGMCC 3917 using only waste beer yeast as nutrient source.  

PubMed

In order to improve the use of waste beer yeast (WBY) for bacterial cellulose production by Gluconacetobacter hansenii CGMCC 3917, a two-step pre-treatment was designed. First WBY was treated by 4 methods: 0.1M NaOH treatment, high speed homogenizer, ultrasonication and microwave treatment followed by hydrolysis (121°C, 20 min) under mild acid condition (pH 2). The optimal pre-treatment conditions were evaluated by the reducing sugar yield after hydrolysis. 15% WBY treated by ultrasonication for 40 min had the highest reducing sugar yield (29.19%), followed by NaOH treatment (28.98%), high speed homogenizer (13.33%) and microwaves (13.01%). Treated WBY hydrolysates were directly supplied as only nutrient source for BC production. A sugar concentration of 3% WBY hydrolysates treated by ultrasonication gave the highest BC yield (7.02 g/L), almost 6 times as that from untreated WBY (1.21 g/L). Furthermore, the properties of the BC were as good as those obtained from the conventional chemical media. PMID:24212131

Lin, Dehui; Lopez-Sanchez, Patricia; Li, Rui; Li, Zhixi

2014-01-01

431

Effect of reduction in yeast and enzyme concentrations in a simultaneous- saccharification-and-fermentation-based bioethanol process: technical and economic evaluation.  

PubMed

The ethanol production cost in a simultaneous saccharification and fermentation-based bioethanol process is influenced by the requirements for yeast production and for enzymes. The main objective of this study was to evaluate--technically and economically--the influence of these two factors on the production cost. A base case with 5 g/L of baker's yeast and an initial concentration of water-insoluble solids of 5% resulted in an experimental yield of 85%. When these data were implemented in Aspen Plus, yeast was assumed to be produced from sugars in the hydrolysate, reducing the overall ethanol yield to 69%. The ethanol production cost was 4.80 SEK/L (2.34 US$/gal). When adapted yeast was used at 2 g/L, an experimental yield of 74% was achieved and the estimated ethanol production cost was the same as in the base case. A 50% reduction in enzyme addition resulted in an increased production cost, to 5.06 SEK/L (2.47 US$/gal) owing to reduced ethanol yield. PMID:15920258

Wingren, Anders; Galbe, Mats; Roslander, Christian; Rudolf, Andreas; Zacchi, Guido

2005-01-01

432

Bioethanol production from the nutrient stress-induced microalga Chlorella vulgaris by enzymatic hydrolysis and immobilized yeast fermentation.  

PubMed

The microalga Chlorella vulgaris is a potential feedstock for bioenergy due to its rapid growth, carbon dioxide fixation efficiency, and high accumulation of lipids and carbohydrates. In particular, the carbohydrates in microalgae make them a candidate for bioethanol feedstock. In this study, nutrient stress cultivation was employed to enhance the carbohydrate content of C. vulgaris. Nitrogen limitation increased the carbohydrate content to 22.4% from the normal content of 16.0% on dry weight basis. In addition, several pretreatment methods and enzymes were investigated to increase saccharification yields. Bead-beating pretreatment increased hydrolysis by 25% compared with the processes lacking pretreatment. In the enzymatic hydrolysis process, the pectinase enzyme group was superior for releasing fermentable sugars from carbohydrates in microalgae. In particular, pectinase from Aspergillus aculeatus displayed a 79% saccharification yield after 72h at 50°C. Using continuous immobilized yeast fermentation, microalgal hydrolysate was converted into ethanol at a yield of 89%. PMID:24333701

Kim, Kyoung Hyoun; Choi, In Seong; Kim, Ho Myeong; Wi, Seung Gon; Bae, Hyeun-Jong

2014-02-01

433

Oxidative stress responses in yeast  

Microsoft Academic Search

Yeast, and especially S. cerevisiae, is a unique eukaryotic model organism for studying oxidative stress and its cellular responses. S. cerevisiae has become a very powerful tool to decipher the complexity of these biologically important responses, because it offers the\\u000a relative simplicity of a single celled eukaryotic organism that enables the combination and integration of genetic, biochemical,\\u000a physico-chemical, cell biological,

Michel B. Toledano; Agnes Delaunay; Benoit Biteau; Daniel Spector; Dulce Azevedo

434

Yeast adaptation on softwood prehydrolysate  

Microsoft Academic Search

Several strains and genera of yeast, includingSaccharomyces cerevisiae D5A,Pachysolen tannophilus, S. cerevisiae K-l,Brettanomyces custersii, Candida shehatae, andCandida acidothermophilum, are screened for growth on dilute acid-pretreated softwood prehydrolysate. Selected softwood species found in forest underbrush\\u000a of the western United States, which contain predominantly hexosan hemicellulose, were studied. This phase of the work emphasized\\u000a debarked Douglas fir. The two best initial isolates

Fcred A. Keller; Delicia Bates; Ray Ruiz; Quang Nguyen

1998-01-01

435

Isolation and Screening of Yeasts That Ferment d-Xylose Directly to Ethanol  

PubMed Central

Natural habitats of yeasts were examined for the presence of strains able to produce ethanol from d-xylose. Black knots, insect frass, and tree exudates were screened by enrichment in liquid d-xylose-yeast extract medium. These and each d-xylose-assimilating yeast in a collection from cactus fruits and Drosophila spp. were tested for alcohol production from this sugar. Among the 412 isolates examined, 36 produced more than 1 g of ethanol liter?1 from 20 g of d-xylose liter?1, all under aerated conditions. Closer examination of the strains indicated that their time courses of d-xylose fermentation followed different patterns. Some strains produced more biomass than ethanol, and among these, ethanol may or may not be assimilated rapidly after depletion of d-xylose. Others produced more ethanol than biomass, but all catabolized ethanol after carbohydrate exhaustion. Ethanol production appeared best at low pH values and under mild aeration. Possible correlations between the nutritional profiles of the yeasts and their ability to produce ethanol from d-xylose were explored by multivariate analysis. d-Xylose appeared slightly better utilized by yeasts which rate poorly in terms of fermentation. The fermentation of d-glucose had no bearing on d-xylose fermentation. No specific nutritional trait could discriminate well between better d-xylose fermentors and other yeasts. PMID:16346947

Nigam, J. N.; Ireland, R. S.; Margaritis, A.; Lachance, M. A.

1985-01-01

436

Synthesis and in vitro antioxidant functions of protein hydrolysate from backbones of Rastrelliger kanagurta by proteolytic enzymes  

PubMed Central

Every year, a huge quantity of fishery wastes and by-products are generated by fish processing industries. These wastes are either underutilized to produce low market value products or dumped leading to environmental issues. Complete utilization of fishery wastes for recovering value added products would be beneficial to the society and individual. The fish protein hydrolysates and derived peptides of fishery resources are widely used as nutritional supplements, functional ingredients, and flavor enhancers in food, beverage and pharmaceutical industries. Antioxidants from fishery resources have attracted the attention of researchers as they are cheaper in cost, easy to derive, and do not have side effects. Thus the present investigation was designed to produce protein hydrolysate by pepsin and papain digestion from the backbones of Rastrelliger kanagurta (Indian mackerel) and evaluate its antioxidant properties through various in vitro assays. The results reveal that both hydrolysates are potent antioxidants, capable of scavenging 46% and 36% of DPPH (1,1-diphenyl-2 picrylhydrazyl) and 58.5% and 37.54% of superoxide radicals respectively. The hydrolysates exhibit significant (p < 0.05) reducing power and lipid peroxidation inhibition. Among the two hydrolysates produced, pepsin derived fraction is superior than papain derived fraction in terms of yield, DH (Degree of hydrolysis), and antioxidant activity. PMID:24596496

Sheriff, Sheik Abdulazeez; Sundaram, Balasubramanian; Ramamoorthy, Baranitharan; Ponnusamy, Ponmurugan

2013-01-01

437

Production of flavour-active methionol from methionine metabolism by yeasts in coconut cream.  

PubMed

Yeasts Candida kefyr NCYC143, Candida utilis CUM, Kluyveromyces lactis KL71, Saccharomyces bayanus SB1, Saccharomyces cerevisiae EC1118, Saccharomyces chevalieri CCICC1028, Candida famata (previously Torulopsis candida) CCICC1041 and Williopsis saturnus var. saturnus CBS254 were screened for their ability to produce flavour-active methionol (3-methylthio-1-propanol) in coconut cream supplemented with l-methionine. The yeasts varied with their ability to produce methionol from methionine with Saccharomyces cerevisiae EC1118 producing the most, followed by Kluyveromyces lactis KL71. Little methionol was produced by the other yeasts. Methionol production by Kluyveromyces lactis KL71 was subjected to further studies under different conditions of initial pH (4.0-6.3), temperature (20-33 °C), l-methionine concentration (0.05-0.25%) and yeast extract concentration (0-0.50%); optimal conditions were established at pH 5.0, 33.0 °C, 0.15% l-methionine and 0.05% yeast extract. CharmAnalysis™ using SPME-GC-MS was conducted on the coconut cream ferment; methional (3-methylthio-1-propanal), methionol and 2-phenylethyl acetate were found to be the most potent aroma-active compounds. The product of coconut cream fermentation by Kluyveromyces lactis KL71 may be considered as a novel, plant-based, natural and complex flavoring bioingredient in food applications. PMID:20805008

Seow, Yi-Xin; Ong, Peter K C; Liu, Shao-Quan

2010-10-15

438

An indirect assay for volatile compound production in yeast strains  

PubMed Central

Traditional flavor analysis relies on gas chromatography coupled to mass spectrometry (GC-MS) methods. Here we describe an indirect method coupling volatile compound formation to an ARO9-promoter-LacZ reporter gene. The resulting ?-galactosidase activity correlated well with headspace solid phase micro extraction (HS/SPME) GC-MS data, particularly with respect to the formation of rose flavor. This tool enables large-scale screening of yeast strains and their progeny to identify the most flavor active strains. PMID:24424137

Ravasio, Davide; Walther, Andrea; Trost, Kajetan; Vrhovsek, Urska; Wendland, Jurgen

2014-01-01

439

Antimicrobial effect of various combinations of plant extracts  

Microsoft Academic Search

The combined extracts of corni fructus, cinnamon and Chinese chive were used to evaluate its antimicrobial activity on common foodborne micro-organisms, including bacteria, yeasts and moulds. The combined extract (8:1:1, v\\/v\\/v) showed an entire antimicrobial spectrum and outstanding inhibitory effect. The combined extract was very stable under heat treatment. The inhibitory effect of the combined extract was greater with more

Pao-Chuan Hsieh; Jeng-Leun Mau; Shu-Hui Huang

2001-01-01

440

Biodegradation of Oil Pollutants by Yeasts and Yeast-Like Fungi.  

National Technical Information Service (NTIS)

In exploring the feasibility of the use of microbial systems for the facilitated biodegradation of waste oils, yeasts and yeast-like fungi from marine, freshwater and terrestrial sources were screened for their ability to utilize hydrocarbons. Mixed cultu...

D. G. Ahearn, N. H. Berner

1978-01-01