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Sample records for yeast extract hydrolysate

  1. 40 CFR 180.1246 - Yeast Extract Hydrolysate from Saccharomyces cerevisiae: exemption from the requirement of a...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 24 2014-07-01 2014-07-01 false Yeast Extract Hydrolysate from... PESTICIDE CHEMICAL RESIDUES IN FOOD Exemptions From Tolerances § 180.1246 Yeast Extract Hydrolysate from... exemption from the requirement of a tolerance for residues of the biochemical pesticide Yeast...

  2. 40 CFR 180.1246 - Yeast Extract Hydrolysate from Saccharomyces cerevisiae: exemption from the requirement of a...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 25 2012-07-01 2012-07-01 false Yeast Extract Hydrolysate from... PESTICIDE CHEMICAL RESIDUES IN FOOD Exemptions From Tolerances § 180.1246 Yeast Extract Hydrolysate from... exemption from the requirement of a tolerance for residues of the biochemical pesticide Yeast...

  3. 40 CFR 180.1246 - Yeast Extract Hydrolysate from Saccharomyces cerevisiae: exemption from the requirement of a...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 25 2013-07-01 2013-07-01 false Yeast Extract Hydrolysate from... PESTICIDE CHEMICAL RESIDUES IN FOOD Exemptions From Tolerances § 180.1246 Yeast Extract Hydrolysate from... exemption from the requirement of a tolerance for residues of the biochemical pesticide Yeast...

  4. 40 CFR 180.1246 - Yeast Extract Hydrolysate from Saccharomyces cerevisiae: exemption from the requirement of a...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Saccharomyces cerevisiae: exemption from the requirement of a tolerance. 180.1246 Section 180.1246 Protection of... Saccharomyces cerevisiae: exemption from the requirement of a tolerance. This regulation establishes an... Hydrolysate from Saccharomyces cerevisiae on all food commodities when applied/used for the management...

  5. 40 CFR 180.1246 - Yeast Extract Hydrolysate from Saccharomyces cerevisiae: exemption from the requirement of a...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Saccharomyces cerevisiae: exemption from the requirement of a tolerance. 180.1246 Section 180.1246 Protection of... Saccharomyces cerevisiae: exemption from the requirement of a tolerance. This regulation establishes an... Hydrolysate from Saccharomyces cerevisiae on all food commodities when applied/used for the management...

  6. Membrane Extraction for Detoxification of Biomass Hydrolysates

    SciTech Connect

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

    2012-05-01

    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.

  7. Bioprocessing of bagasse hydrolysate for ethanol and xylitol production using thermotolerant yeast.

    PubMed

    Kumar, Sachin; Dheeran, Pratibha; Singh, Surendra P; Mishra, Indra M; Adhikari, Dilip K

    2015-01-01

    Fermentation of xylose-rich and glucose-rich bagasse hydrolysates, obtained from the two-stage acid hydrolysis was studied using the thermotolerant yeast Kluyveromyces sp. IIPE453. The yeast could grow on xylose-rich hydrolysate at 50C with the dry cell weight, cell mass yield and maximum specific growth rate of 5.35gl(-1), 0.58gg(-1) and 0.13h(-1), respectively. The yeast was found to be very promising for ethanol as well as xylitol production from the sugars obtained from the lignocellulosic biomass. Batch fermentations of xylose-rich and glucose-rich hydrolysates yielded 0.61gg(-1) xylitol and 0.43gg(-1) ethanol in the broth, respectively based on the sugars present in the hydrolysate. Overall ethanol yield of 165g (210ml) and 183g xylitol per kg of bagasse was obtained, when bagasse hydrolysate was used as a substrate. Utilization of both the glucose and xylose sugars makes the process most economical by producing both ethanol and xylitol based on biorefinery concept. On validating the experimental data of ethanol fermentation, the modified Luong kinetic model for product inhibition as well as inhibition due to inhibitory compounds present in hydrolysate, the model was found to be the best fit for ethanol formation from bagasse hydrolysate using Kluyveromyces sp. IIPE453. PMID:25090978

  8. Yeast strains for ethanol production from lignocellulosic hydrolysates during in situ detoxification.

    PubMed

    Tian, Shen; Zhou, Guixiong; Yan, Fei; Yu, Yong; Yang, Xiushan

    2009-01-01

    Yeast strains Y1, Y4 and Y7 demonstrated high conversion efficiencies for sugars and high abilities to tolerate or metabolize inhibitors in dilute-acid lignocellulosic hydrolysates. Strains Y1 and Y4 completely consumed the glucose within 24 h in dilute-acid lignocellulosic hydrolysate during in situ detoxification, and the maximum ethanol yields reached 0.49 g and 0.45 g ethanol/g glucose, equivalent to maximum theoretical values of 96% and 88.2%, respectively. Strain Y1 could metabolize xylose to xylitol with a yield of 0.64 g/g xylose, whereas Y4 was unable to utilize xylose as a substrate. Strain Y7 was able to consume sugars (glucose and xylose) within 72 h during hydrolysate in situ detoxification, producing a high ethanol yield (equivalent to 93.6% of the maximum theoretical value). Y1 and Y7 are the most efficient yeast strains yet reported for producing ethanol from non-detoxified dilute-acid lignocellulosic hydrolysates. These findings offer huge potential for improving the economics of bio-ethanol production from lignocellulosic hydrolysates. PMID:19393310

  9. Beneficial effect of corncob acid hydrolysate on the lipid production by oleaginous yeast Trichosporon dermatis.

    PubMed

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

    2015-01-01

    In this work, corncob acid hydrolysate and its simulated medium whose sugar composition was the same as the corncob acid hydrolysate were used as fermentation substrate for lipid production by oleaginous yeast Trichosporon dermatis. On the corncob acid hydrolysate, after 7 days of fermentation, the biomass, lipid content, lipid yield, and lipid coefficient of T. dermatis were 17.3 g/L, 40.2%, 7.0 g/L, and 16.5%, respectively. Interestingly, during the lipid fermentation on the corncob acid hydrolysate, glucose, xylose, arabinose, and even acetic acid could be well utilized as carbon sources by T. dermatis. Surprisingly, the lipid yield (7.0 g/L) of T. dermatis on the corncob acid hydrolysate was much higher than that (3.8 g/L) on the simulated medium, in spite of the fact that the lipid coefficient (17.4%) on the simulated medium was a little higher. This phenomenon further showed that lignocellulosic acid hydrolysate was a suitable substrate for lipid fermentation by T. dermatis. This work would help the comprehensive utilization of lignocellulosic biomass for lipid production. PMID:24840672

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

    DOEpatents

    Ingram, Lonnie O.

    2000-01-01

    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.

  11. Identification of furfural as a key toxin in lignocellulosic hydrolysates and evolution of a tolerant yeast strain

    PubMed Central

    Heer, Dominik; Sauer, Uwe

    2008-01-01

    Summary The production of fuel ethanol from low?cost lignocellulosic biomass currently suffers from several limitations. One of them is the presence of inhibitors in lignocellulosic hydrolysates that are released during pre?treatment. These compounds inhibit growth and hamper the production of ethanol, thereby affecting process economics. To delineate the effects of such complex mixtures, we conducted a chemical analysis of four different real?world lignocellulosic hydrolysates and determined their toxicological effect on yeast. By correlating the potential inhibitor abundance to the growth?inhibiting properties of the corresponding hydrolysates, we identified furfural as an important contributor to hydrolysate toxicity for yeast. Subsequently, we conducted a targeted evolution experiment to improve growth behaviour of the half industrial Saccharomyces cerevisiae strain TMB3400 in the hydrolysates. After about 300 generations, representative clones from these evolved populations exhibited significantly reduced lag phases in medium containing the single inhibitor furfural, but also in hydrolysate?supplemented medium. Furthermore, these strains were able to grow at concentrations of hydrolysates that effectively killed the parental strain and exhibited significantly improved bioconversion characteristics under industrially relevant conditions. The improved resistance of our evolved strains was based on their capacity to remain viable in a toxic environment during the prolonged, furfural induced lag phase. PMID:21261870

  12. Identification of furfural as a key toxin in lignocellulosic hydrolysates and evolution of a tolerant yeast strain.

    PubMed

    Heer, Dominik; Sauer, Uwe

    2008-11-01

    The production of fuel ethanol from low-cost lignocellulosic biomass currently suffers from several limitations. One of them is the presence of inhibitors in lignocellulosic hydrolysates that are released during pre-treatment. These compounds inhibit growth and hamper the production of ethanol, thereby affecting process economics. To delineate the effects of such complex mixtures, we conducted a chemical analysis of four different real-world lignocellulosic hydrolysates and determined their toxicological effect on yeast. By correlating the potential inhibitor abundance to the growth-inhibiting properties of the corresponding hydrolysates, we identified furfural as an important contributor to hydrolysate toxicity for yeast. Subsequently, we conducted a targeted evolution experiment to improve growth behaviour of the half industrial Saccharomyces cerevisiae strain TMB3400 in the hydrolysates. After about 300 generations, representative clones from these evolved populations exhibited significantly reduced lag phases in medium containing the single inhibitor furfural, but also in hydrolysate-supplemented medium. Furthermore, these strains were able to grow at concentrations of hydrolysates that effectively killed the parental strain and exhibited significantly improved bioconversion characteristics under industrially relevant conditions. The improved resistance of our evolved strains was based on their capacity to remain viable in a toxic environment during the prolonged, furfural induced lag phase. PMID:21261870

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

    PubMed

    Latté, K P; Kolodziej, H

    2000-01-01

    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

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

    PubMed

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

    2011-05-01

    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

  15. Citric acid production from Aspergillus niger MT-4 using hydrolysate extract of the insect Locusta migratoria.

    PubMed

    Taskin, Mesut; Tasar, Gani Erhan; Incekara, Umit

    2013-06-01

    Citric acid (CA) is the most important organic acid used in the food and other industries. Locusta migratoria is an insect species, which has rich nutritional composition (especially protein) and cultivated in some countries. Therefore, the present study investigated the usability of hydrolysate extract of L. migratoria biomass as substrate for the production of CA from Aspergillus niger MT-4. The insect extract (IE) was found to be rich in ash (34.9 g/100 g), protein (35.6 g/100 g) and mineral contents. Yeast extract was found to be the most favorable substrate for biomass production, whereas the maximum production of CA (41.8 g/L) was achieved in the medium containing IE. Besides, uniform pellets with the smallest size (4 mm) were observed in IE medium. It was thought that rich magnesium (6.78 g/100 g) and manganese (1.14 g/100 g) contents of IE increased the production of CA, resulting in the formation of small uniform pellets. This is the first report on the effect of protein-rich insect biomasses on the production of CA. In this regard, L. migratoria biomass was tested for the first time as a CA-production substrate. PMID:22323475

  16. Detoxification of Eucheuma spinosum Hydrolysates with Activated Carbon for Ethanol Production by the Salt-Tolerant Yeast Candida tropicalis.

    PubMed

    Ra, Chae Hun; Jung, Jang Hyun; Sunwoo, In Young; Kang, Chang Han; Jeong, Gwi-Taek; Kim, Sung-Koo

    2015-06-01

    The objective of this study was to optimize the slurry contents and salt concentrations for ethanol production from hydrolysates of the seaweed Eucheuma spinosum. A monosaccharide concentration of 44.2 g/l as 49.6% conversion of total carbohydrate of 89.1 g/l was obtained from 120 g dw/l seaweed slurry. Monosaccharides from E. spinosum slurry were obtained by thermal acid hydrolysis and enzymatic hydrolysis. Addition of activated carbon at 2.5% (w/v) and the adsorption time of 2 min were used in subsequent adsorption treatments to prevent the inhibitory effect of HMF. The adsorption surface area of the activated carbon powder was 1,400-1,600 m(2)/g and showed selectivity to 5-hydroxymethyl furfural (HMF) from monosaccharides. Candida tropicalis KCTC 7212 was cultured in yeast extract, peptone, glucose, and high-salt medium, and exposed to 80, 90, 100, and 110 practical salinity unit (psu) salt concentrations in the lysates. The 100 psu salt concentration showed maximum cell growth and ethanol production. The ethanol fermentations with activated carbon treatment and use of C. tropicalis acclimated to a high salt concentration of 100 psu produced 17.9 g/l of ethanol with a yield (YEtOH) of 0.40 from E. spinosum seaweed. PMID:25649983

  17. 21 CFR 172.590 - Yeast-malt sprout extract.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Yeast-malt sprout extract. 172.590 Section 172.590... Substances § 172.590 Yeast-malt sprout extract. Yeast-malt sprout extract, as described in this section, may... produced by partial hydrolysis of yeast extract (derived from Saccharomyces cereviseae,...

  18. 21 CFR 184.1983 - Bakers yeast extract.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Bakers yeast extract. 184.1983 Section 184.1983... Listing of Specific Substances Affirmed as GRAS § 184.1983 Bakers yeast extract. (a) Bakers yeast extract... a selected strain of yeast, Saccharomyces cerevisiae. It may be concentrated or dried. (b)...

  19. 21 CFR 172.590 - Yeast-malt sprout extract.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Yeast-malt sprout extract. 172.590 Section 172.590... CONSUMPTION Flavoring Agents and Related Substances § 172.590 Yeast-malt sprout extract. Yeast-malt sprout... prescribed conditions: (a) The additive is produced by partial hydrolysis of yeast extract (derived...

  20. 21 CFR 184.1983 - Bakers yeast extract.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Bakers yeast extract. 184.1983 Section 184.1983... GRAS § 184.1983 Bakers yeast extract. (a) Bakers yeast extract is the food ingredient resulting from concentration of the solubles of mechanically ruptured cells of a selected strain of yeast,...

  1. 21 CFR 184.1983 - Bakers yeast extract.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Bakers yeast extract. 184.1983 Section 184.1983... Listing of Specific Substances Affirmed as GRAS § 184.1983 Bakers yeast extract. (a) Bakers yeast extract... a selected strain of yeast, Saccharomyces cerevisiae. It may be concentrated or dried. (b)...

  2. 21 CFR 172.590 - Yeast-malt sprout extract.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Yeast-malt sprout extract. 172.590 Section 172.590... CONSUMPTION Flavoring Agents and Related Substances § 172.590 Yeast-malt sprout extract. Yeast-malt sprout... prescribed conditions: (a) The additive is produced by partial hydrolysis of yeast extract (derived...

  3. 21 CFR 184.1983 - Bakers yeast extract.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Bakers yeast extract. 184.1983 Section 184.1983... Listing of Specific Substances Affirmed as GRAS § 184.1983 Bakers yeast extract. (a) Bakers yeast extract... a selected strain of yeast, Saccharomyces cerevisiae. It may be concentrated or dried. (b)...

  4. 21 CFR 172.590 - Yeast-malt sprout extract.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Yeast-malt sprout extract. 172.590 Section 172.590... CONSUMPTION Flavoring Agents and Related Substances § 172.590 Yeast-malt sprout extract. Yeast-malt sprout... prescribed conditions: (a) The additive is produced by partial hydrolysis of yeast extract (derived...

  5. 21 CFR 184.1983 - Bakers yeast extract.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Bakers yeast extract. 184.1983 Section 184.1983... Listing of Specific Substances Affirmed as GRAS § 184.1983 Bakers yeast extract. (a) Bakers yeast extract... a selected strain of yeast, Saccharomyces cerevisiae. It may be concentrated or dried. (b)...

  6. 21 CFR 172.590 - Yeast-malt sprout extract.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Yeast-malt sprout extract. 172.590 Section 172.590... CONSUMPTION Flavoring Agents and Related Substances § 172.590 Yeast-malt sprout extract. Yeast-malt sprout... prescribed conditions: (a) The additive is produced by partial hydrolysis of yeast extract (derived...

  7. Bactericidal effect of hydrolysable and condensed tannin extracts on Campylobacter jejuni in vitro.

    PubMed

    Anderson, Robin C; Vodovnik, Maša; Min, Byeng R; Pinchak, William E; Krueger, Nathan A; Harvey, Roger B; Nisbet, David J

    2012-07-01

    Strategies are sought to reduce intestinal colonisation of food-producing animals by Campylobacter jejuni, a leading bacterial cause of human foodborne illness worldwide. Presently, we tested the antimicrobial activity of hydrolysable-rich blackberry, cranberry and chestnut tannin extracts and condensed tannin-rich mimosa, quebracho and sorghum tannins (each at 100 mg/mL) against C. jejuni via disc diffusion assay in the presence of supplemental casamino acids. We found that when compared to non-tannin-treated controls, all tested tannins inhibited the growth of C. jejuni and that inhibition by the condensed tannin-rich mimosa and quebracho extracts was mitigated in nutrient-limited medium supplemented with casamino acids. When tested in broth culture, both chestnut and mimosa extracts inhibited growth of C. jejuni and this inhibition was much greater in nutrient-limited than in full-strength medium. Consistent with observations from the disc diffusion assay, the inhibitory activity of the condensed tannin-rich mimosa extracts but not the hydrolysable tannin-rich chestnut extracts was mitigated by casamino acid supplementation to the nutrient-limited medium, likely because the added amino acids saturated the binding potential of the condensed tannins. These results demonstrate the antimicrobial activity of various hydrolysable and condensed tannin-rich extracts against C. jejuni and reveal that condensed tannins may be less efficient than hydrolysable tannins in controlling C. jejuni in gut environments containing high concentrations of amino acids and soluble proteins. PMID:22528299

  8. Novel strategies to improve co-fermentation of pentoses with D-glucose by recombinant yeast strains in lignocellulosic hydrolysates.

    PubMed

    Oreb, Mislav; Dietz, Heiko; Farwick, Alexander; Boles, Eckhard

    2012-01-01

    Economically feasible production of second-generation biofuels requires efficient co-fermentation of pentose and hexose sugars in lignocellulosic hydrolysates under very harsh conditions. Baker's yeast is an excellent, traditionally used ethanol producer but is naturally not able to utilize pentoses. This is due to the lack of pentose-specific transporter proteins and enzymatic reactions. Thus, natural yeast strains must be modified by genetic engineering. Although the construction of various recombinant yeast strains able to ferment pentose sugars has been described during the last two decades, their rates of pentose utilization is still significantly lower than D-glucose fermentation. Moreover, pentoses are only fermented after D-glucose is exhausted, resulting in an uneconomical increase in the fermentation time. In this addendum, we discuss novel approaches to improve utilization of pentoses by development of specific transporters and substrate channeling in enzyme cascades. PMID:22892590

  9. Bactericidal effect of hydrolysable and condensed tannin extracts on Campylobacter jejuni in vitro

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Strategies are sought to reduce intestinal colonization of food-producing animals by Campylobacter jejuni, a leading bacterial cause of human foodborne illness worldwide. Presently, we tested the antimicrobial activity of hydrolysable-rich blackberry, cranberry, chestnut tannin extracts, and conden...

  10. Lipid Production from Hemicellulose and Holocellulose Hydrolysate of Palm Empty Fruit Bunches by Newly Isolated Oleaginous Yeasts.

    PubMed

    Tampitak, Srikanya; Louhasakul, Yasmi; Cheirsilp, Benjamas; Prasertsan, Poonsuk

    2015-07-01

    Palm empty fruit bunches (EFBs) are abundant lignocellulosic wastes from palm oil mills. They are potential sources of sugars which can be converted to microbial lipids by oleaginous yeasts. To produce sugars from EFB, two-step and one-step hydrolysis reactions were performed. In the first step, the use of diluted sulfuric acid (0.5 % w/v) hydrolyzed hemicelluloses and released mainly pentoses, and in the second step of hydrolysis of residual pulp using 2.5 % (w/v), sulfuric acid released more hexoses. The use of 2.5 % (w/v) sulfuric acid in one-step hydrolysis of holocelluloses released the highest amount of sugars (38.3 g/L), but it also produced high concentration of potential inhibitors (>1 g/L). Three oleaginous yeasts, Rhodotorula mucilaginosa, Kluyveromyces marxianus, and Candida tropicalis, were isolated and screened for their ability to convert EFB hydrolysates into lipids. These yeasts grew well and produced lipids from EFB hemicellulose and holocellulose hydrolysate after potential inhibitors were removed. This study shows that EFB can be used for lipid production. PMID:26026262

  11. Hydrolysate of lipid extracted microalgal biomass residue: An algal growth promoter and enhancer.

    PubMed

    Maurya, Rahulkumar; Paliwal, Chetan; Chokshi, Kaumeel; Pancha, Imran; Ghosh, Tonmoy; Satpati, Gour Gopal; Pal, Ruma; Ghosh, Arup; Mishra, Sandhya

    2016-05-01

    The present study demonstrates the utilization of the algal hydrolysate (AH) prepared from lipid extracted residual harmful bloom-forming cyanobacteria Lyngbya majuscula biomass, as a growth supplement for the cultivation of green microalgae Chlorella vulgaris. BG-11 replacements with AH in different proportions significantly affects the cell count, dry cell weight (DCW), biomass productivity (BP) and pigments concentration. Among all, 25% AH substitution in BG11 media was found to be optimum which enhanced DCW, BP and pigments content by 39.13%, 40.81% and 129.47%, respectively, compared to control. The lipid content (31.95%) was also significantly higher in the 25% AH replacement. The volumetric productivity of neutral lipids (ideal for biodiesel) and total protein content of the cells significantly increased in all AH substitutions. Thus, lipid extracted microalgal biomass residue (LMBR) hydrolysate can be a potential growth stimulating supplement for oleaginous microalgae C. vulgaris. PMID:26890794

  12. Evaluation of yeast strains for production of fuel ethanol from biomass hydrolysates

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Robust industrial yeast strains are needed for profitable production of fuel ethanol from mixed biomass waste. USDA, ARS, NCAUR, RPT has been evaluating ethanol-producing yeasts, including Saccharomyces cerevisiae, engineered GMAX Saccharomyces cerevisiae, irradiated Kluyveromyces marxianus, and Pi...

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

    PubMed

    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

    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 (42C), 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

  14. Liquid-liquid extraction of fermentation inhibiting compounds in lignocellulose hydrolysate.

    PubMed

    Zautsen, R R M; Maugeri-Filho, F; Vaz-Rossell, C E; Straathof, A J J; van der Wielen, L A M; de Bont, J A M

    2009-04-01

    Several compounds that are formed or released during hydrolysis of lignocellulosic biomass inhibit the fermentation of the hydrolysate. The use of a liquid extractive agent is suggested as a method for removal of these fermentation inhibitors. The method can be applied before or during the fermentation. For a series of alkanes and alcohols, partition coefficients were measured at low concentrations of the inhibiting compounds furfural, hydroxymethyl furfural, vanillin, syringaldehyde, coniferyl aldehyde, acetic acid, as well as for ethanol as the fermentation product. Carbon dioxide production was measured during fermentation in the presence of each organic solvent to indicate its biocompatibility. The feasibility of extractive fermentation of hydrolysate was investigated by ethanolic glucose fermentation in synthetic medium containing several concentrations of furfural and vanillin and in the presence of decanol, oleyl alcohol and oleic acid. Volumetric ethanol productivity with 6 g/L vanillin in the medium increased twofold with 30% volume oleyl alcohol. Decanol showed interesting extractive properties for most fermentation inhibiting compounds, but it is not suitable for in situ application due to its poor biocompatibility. PMID:19062184

  15. Preparation of Yeast Hydrolysate Enriched in Cyclo-His-Pro (CHP) by Enzymatic Hydrolysis and Evaluation of Its Functionality

    PubMed Central

    Lee, Hyun Jung; Son, Heung Soo; Park, Chung; Suh, Hyung Joo

    2015-01-01

    In this study, we attempted to enrich cyclo-His-Pro (CHP) using enzymatic hydrolysis of yeast and to evaluate the functionality of yeast hydrolysate (YH)-enriched CHP. Flavourzyme offered a better performance in enhancing CHP content than other proteases. The CHP enrichment conditions were optimized as follows: addition of 1% Flavourzyme, 48-h incubation at 60°C, and pH 6.0. The CHP content significantly increased by 20-fold after ultra-filtration (UF). Maximal CHP translation was obtained after heating for 8 h at 50°C and pH 7.0. YH showed poor foaming capacity between pH 3.0 to 9.0. The emulsifying activities of YHs were slightly higher at near acidic pH. Increase in heating temperature and time resulted in decreased CHP content. The results indicate that YH is more heat stable after UF. Therefore, the CHP in YH after UF can be used as a food additive with physiological CHP activity and high heat stability. PMID:26770916

  16. Preparation of Yeast Hydrolysate Enriched in Cyclo-His-Pro (CHP) by Enzymatic Hydrolysis and Evaluation of Its Functionality.

    PubMed

    Lee, Hyun Jung; Son, Heung Soo; Park, Chung; Suh, Hyung Joo

    2015-12-01

    In this study, we attempted to enrich cyclo-His-Pro (CHP) using enzymatic hydrolysis of yeast and to evaluate the functionality of yeast hydrolysate (YH)-enriched CHP. Flavourzyme offered a better performance in enhancing CHP content than other proteases. The CHP enrichment conditions were optimized as follows: addition of 1% Flavourzyme, 48-h incubation at 60°C, and pH 6.0. The CHP content significantly increased by 20-fold after ultra-filtration (UF). Maximal CHP translation was obtained after heating for 8 h at 50°C and pH 7.0. YH showed poor foaming capacity between pH 3.0 to 9.0. The emulsifying activities of YHs were slightly higher at near acidic pH. Increase in heating temperature and time resulted in decreased CHP content. The results indicate that YH is more heat stable after UF. Therefore, the CHP in YH after UF can be used as a food additive with physiological CHP activity and high heat stability. PMID:26770916

  17. Antioxidant Properties of Fish Protein Hydrolysates Prepared from Cod Protein Hydrolysate by Bacillus sp.

    PubMed

    Godinho, I; Pires, C; Pedro, S; Teixeira, B; Mendes, R; Nunes, M L; Batista, I

    2016-03-01

    Fermentative protein hydrolysates (FPH) were prepared with a proteolytic bacterium, Bacillus strain exhibiting high proteolytic activity. Three FPH with 1, 2, and 4 % of cod protein hydrolysate (CPH) and 0.5 % of yeast extract in the culture were prepared. The yields achieved varied between 30 and 58 % based on protein content. A general decrease of leucine, isoleucine, valine, alanine, arginine, threonine, proline, and glutamic acid was observed. All FPHs showed higher reducing power and DPPH radical scavenging activity than CPH, but similar ABTS radical scavenging activity. However, FPHs exhibited lower Cu(+2)-chelating activity than CPH. The ACE inhibitory activity of FPHs was not improved relatively to that recorded in CPH. The fermentative process seems to have potential to obtaining hydrolysates with improved biological activities or even to produce protein hydrolysates from native fish proteins. PMID:26590847

  18. Production of (R)-3-hydroxybutyric acid by Burkholderia cepacia from wood extract hydrolysates

    PubMed Central

    2014-01-01

    (R)-hydroxyalkanoic acids (R-HAs) are valuable building blocks for the synthesis of fine chemicals and biopolymers because of the chiral center and the two active functional groups. Hydroxyalkanoic acids fermentation can revolutionize the polyhydroxyalkanoic acids (PHA) production by increasing efficiency and enhancing product utility. Modifying the fermentation conditions that promotes the in vivo depolymerization and secretion to fermentation broth in wild type bacteria is a novel and promising approach to produce R-HAs. Wood extract hydrolysate (WEH) was found to be a suitable substrate for R-3-hydroxybutyric acid (R-3-HB) production by Burkholderia cepacia. Using Paulownia elongate WEH as a feedstock, the R-3-HB concentration in fermentation broth reached as high as 14.2 g/L after 3 days of batch fermentation and the highest concentration of 16.8 g/L was obtained at day 9. Further investigation indicated that the composition of culture medium contributed to the enhanced R-3-HB production. PMID:24949263

  19. Yeast hydrolysate supplementation increases field abundance and persistence of sexually mature sterile Queensland fruit fly, Bactrocera tryoni (Froggatt).

    PubMed

    Reynolds, O L; Orchard, B A; Collins, S R; Taylor, P W

    2014-04-01

    The sterile insect technique (SIT) is a non-chemical approach used to control major pests from several insect families, including Tephritidae, and entails the mass-release of sterile insects that reduce fertility of wild populations. For SIT to succeed, released sterile males must mature and compete with wild males to mate with wild females. To reach sexual maturity, the Queensland fruit fly, Bactrocera tryoni (Froggatt) (Diptera: Tephritidae), must obtain adequate nutrition after adult emergence; however, in current SIT programs sterile B. tryoni receive a pre-release diet that lacks key nutrients required to sustain sexual development. The chief objective of this study was to determine whether pre-release yeast hydrolysate (YH) supplements affect the persistence and abundance of sexually mature sterile male B. tryoni under field conditions. Experiments were run in outdoor cages under conditions of low and high environmental stress that differed markedly in temperature and humidity, and in the field. Under low environmental stress conditions, survival of sterile B. tryoni was monitored in cages under three diet treatments: (i) sugar only, (ii) sugar plus YH or (iii) sugar plus YH for 48h and sugar only thereafter. Under high environmental stress conditions survival of sterile B. tryoni was monitored in cages under four diet treatments: (i) white sugar only, (ii) brown sugar only, (iii) white sugar plus YH and (iv) brown sugar plus YH. In a replicated field study, we released colour-marked sterile B. tryoni from two diet regimes, YH-supplemented or YH-deprived, and monitored abundance of sexually mature males. In the low-stress cage study, there was no effect of diet, although overall females lived longer than males. In the high stress cage study, mortality was lower for YH-fed flies than YH-deprived flies and females lived longer than males. In the field, YH supplementation resulted in higher abundance of sexually mature sterile males, with 1.2 YH-fed flies trapped for every YH-deprived fly trapped. Under field conditions, YH supplementation can increase over-flooding ratios and hence may improve the effectiveness of SIT programmes. PMID:24456807

  20. Lipid Production of Heterotrophic Chlorella sp. from Hydrolysate Mixtures of Lipid-Extracted Microalgal Biomass Residues and Molasses.

    PubMed

    Zheng, Hongli; Ma, Xiaochen; Gao, Zhen; Wan, Yiqin; Min, Min; Zhou, Wenguang; Li, Yun; Liu, Yuhuan; Huang, He; Chen, Paul; Ruan, Roger

    2015-10-01

    This study investigated the feasibility of lipid production of Chlorella sp. from waste materials. Lipid-extracted microalgal biomass residues (LMBRs) and molasses were hydrolyzed, and their hydrolysates were analyzed. Five different hydrolysate mixture ratios (w/w) of LMBRs/molasses (1/0, 1/1, 1/4, 1/9, and 0/1) were used to cultivate Chlorella sp. The results showed that carbohydrate and protein were the two main compounds in the LMBRs, and carbohydrate was the main compound in the molasses. The highest biomass concentration of 5.58 g/L, Y biomass/sugars of 0.59 g/g, lipid productivity of 335 mg/L/day, and Y lipids/sugars of 0.25 g/g were obtained at the hydrolysate mixture ratio of LMBRs/molasses of 1/4. High C/N ratio promoted the conversion of sugars into lipids. The lipids extracted from Chlorella sp. shared similar lipid profile of soybean oil and is therefore a potential viable biodiesel feedstock. These results showed that Chlorella sp. can utilize mixed sugars and amino acids from LMBRs and molasses to accumulate lipids efficiently, thus reducing the cost of microalgal biodiesel production and improving its economic viability. PMID:26234438

  1. Herb extracts and collagen hydrolysate improve skin damage resulting from ultraviolet-induced aging in hairless mice.

    PubMed

    Jimbo, Nozomi; Kawada, Chinatsu; Nomura, Yoshihiro

    2015-01-01

    We examined the effect of the daily ingestion of herb extract from Eucommia ulmoides leaves and Korean ginseng on skin damage induced by repeated UV irradiation of hairless mice. The herb extract was orally administered to mice at a dose of 1000 mg/kg/day. The hydration of mice dorsal skin decreased significantly with repeated UV irradiation, but did not decrease when the herb extract was administered for seven weeks. Transepidermal water loss (TEWL) increased with UV irradiation, but decreased with the administration of dietary herb extract. These effects were more pronounced when combined with the administration of collagen hydrolysate. Geniposidic acid from E. ulmoides leaves and ginsenoside Rg1 from Korean ginseng reduced TEWL and increased the skin moisture content of UV-damaged skin on hairless mice, respectively. We concluded that this dietary herb extract reduced the skin damage caused by UV-induced aging, with geniposidic acid and ginsenoside Rg1 detected in the blood. PMID:26011399

  2. Inhibition of spoiling yeasts of fruit juices through citrus extracts.

    PubMed

    Bevilacqua, Antonio; Speranza, Barbara; Campaniello, Daniela; Corbo, Maria Rosaria; Sinigaglia, Milena

    2013-10-01

    This article reports on the bioactivities of citrus extracts (citrus extract, lemon extract, and neroli) toward Saccharomyces cerevisiae, Zygosaccharomyces bailii, Zygosaccharomyces rouxii, Pichia membranifaciens, and Rhodotorula bacarum. The bioactivities of the extracts (from 10 to 100 ppm) were evaluated through a microdilution method; thereafter, citrus extracts (0 to 80 ppm) were tested in combination with either pH (3.0 to 5.0) or temperature (5 to 25°C). Finally, a confirmatory experiment was run in a commercial drink (referred to as red fruit juice) containing citrus extract (40 ppm) that was inoculated with either S. cerevisiae or Z. bailii (5 log CFU/ml) and stored at 4 and 25°C. Yeasts increased to 7 log CFU/ml (Z. bailii) or 8 log CFU/ml (S. cerevisiae) in the control at 25°C, but the citrus extract addition controlled yeast growth for at least 3 days; under refrigeration, the effect was significant for 10 days. PMID:24112576

  3. Sequential recycling of enzymatic lipid-extracted hydrolysate in fermentations with a thraustochytrid.

    PubMed

    Lowrey, Joshua; Armenta, Roberto E; Brooks, Marianne S

    2016-06-01

    This study extends the findings of prior studies proposing and validating nutrient recycling for the heterotrophic microalgae, Thraustochytrium sp. (T18), grown in optimized fed-batch conditions. Sequential nutrient recycling of enzymatically-derived hydrolysate in fermentors succeeded at growing the tested thraustochytrid strain, with little evidence of inhibition or detrimental effects upon culture health. The average maximum biomass obtained in the recycled hydrolysate was 63.68±1.46gL(-1) in 90h the first recycle followed by 65.27±1.15gL(-1) in 90h in the subsequent recycle of the same material. These compared to 58.59gL(-1) and 64.92gL(-1) observed in fresh media in the same time. Lipid production was slightly impaired, however, with a maximum total fatty acid content of 62.2±0.30% in the recycled hydrolysate compared to 69.4% in fresh control media. PMID:26994462

  4. A new yeast producing beta-glucosidase and tolerant to lignocellulose hydrolysate inhibitors for cellulosic ethanol production using SSF

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Conventional cellulose-to-ethanol conversion requires cellulose degradation in order to be utilized for growth and fermentation by common ethanologenic yeast. Cellulose is commonly enzymatically degraded into cellobiose by cellulase and subsequently cellobiose broken down into glucose by beta-glucos...

  5. Systematic identification of yeast proteins extracted into model wine during aging on the yeast lees.

    PubMed

    Rowe, Jeffrey D; Harbertson, James F; Osborne, James P; Freitag, Michael; Lim, Juyun; Bakalinsky, Alan T

    2010-02-24

    Total protein and protein-associated mannan concentrations were measured, and individual proteins were identified during extraction into model wines over 9 months of aging on the yeast lees following completion of fermentations by seven wine strains of Saccharomyces cerevisiae. In aged wines, protein-associated mannan increased about 6-fold (+/-66%), while total protein only increased 2-fold (+/-20%), which resulted in a significantly greater protein-associated mannan/total protein ratio for three strains. A total of 219 proteins were identified among all wine samples taken over the entire time course. Of the 17 "long-lived" proteins detected in all 9 month samples, 13 were cell wall mannoproteins, and four were glycolytic enzymes. Most cytosolic proteins were not detected after 6 months. Native mannosylated yeast invertase was assayed for binding to wine tannin and was found to have a 10-fold lower affinity than nonglycosylated bovine serum albumin. Enrichment of mannoproteins in the aged model wines implies greater solution stability than other yeast proteins and the possibility that their contributions to wine quality may persist long after bottling. PMID:20108898

  6. Quantitative evaluation of intracellular metabolite extraction techniques for yeast metabolomics.

    PubMed

    Canelas, André B; ten Pierick, Angela; Ras, Cor; Seifar, Reza M; van Dam, Jan C; van Gulik, Walter M; Heijnen, Joseph J

    2009-09-01

    Accurate determination of intracellular metabolite levels requires well-validated procedures for sampling and sample treatment. Several methods exist for metabolite extraction, but the literature is contradictory regarding the adequacy and performance of each technique. Using a strictly quantitative approach, we have re-evaluated five methods (hot water, HW; boiling ethanol, BE; chloroform-methanol, CM; freezing-thawing in methanol, FTM; acidic acetonitrile-methanol, AANM) for the extraction of 44 intracellular metabolites (phosphorylated intermediates, amino acids, organic acids, nucleotides) from S. cerevisiae cells. Two culture modes were investigated (batch and chemostat) to check for growth condition dependency, and three targeted platforms were employed (two LC-MS and one GC/MS) to exclude analytical bias. Additionally, for the determination of metabolite recoveries, we applied a novel approach based on addition of (13)C-labeled internal standards at different stages of sample processing. We found that the choice of extraction method can drastically affect measured metabolite levels, to an extent that for some metabolites even the direction of changes between growth conditions can be inverted. The best performances, in terms of efficacy and metabolite recoveries, were achieved with BE and CM, which yielded nearly identical levels for the metabolites analyzed. According to our results, AANM performs poorly in yeast and FTM cannot be considered adequate as an extraction method, as it does not ensure inactivation of enzymatic activity. PMID:19653633

  7. Identifying inhibitory compounds in lignocellulosic biomass hydrolysates using an exometabolomics approach

    PubMed Central

    2014-01-01

    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

  8. Effects of Cyclo-His-Pro-enriched yeast hydrolysate on blood glucose levels and lipid metabolism in obese diabetic ob/ob mice

    PubMed Central

    Jung, Eun Young; Hong, Yang Hee; Park, Chung

    2016-01-01

    BACKGROUND/OBJECTIVES We examined the hypoglycemic and anti-hyperlipidemic effect of yeast hydrolysate (YH) enriched with Cyclo-His-Pro (CHP) in the C57BL/6J ob/ob mouse model. MATERIALS/METHODS Mice were separated into 4 groups (8 mice/group) on the basis of blood glucose and body weight: WT control, lean mice given vehicle; ob/ob control, ob/ob mice given vehicle; YH-1, ob/ob mice given 0.5 g/kg of YH; YH-2, ob/ob mice given 1 g/kg of YH. YH in saline or vehicle was administered orally in the same volume every day for 3 weeks. RESULTS Mice treated with YH (0.5 and 1 g/kg) for 3 weeks displayed a significant reduction in overall body weight gain and perirenal and epididymal adipose tissue weight compared to the ob/ob control group. Additionally, high-density lipoprotein (HDL) cholesterol, glucose, and atherogenic indexes were significantly decreased in the blood of YH-1 and YH-2 groups compared to the ob/ob control. In ob/ob mice, YH administration significantly improved glucose tolerance and blood insulin levels. These data indicate that YH treatment produces potent hypoglycemic and anti-hyperlipidemic effects by controlling body weight, fat mass, blood lipid, insulin levels, and glucose tolerance. CONCLUSION YH could potentially be used as a treatment option for diabetes and hyperlipidemia. The CHP-enriched YH may be a promising strategy in the development of hypoglycemic peptide nutraceuticals. PMID:27087898

  9. Protein Hydrolysates as Hypoallergenic, Flavors and Palatants for Companion Animals

    NASA Astrophysics Data System (ADS)

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

    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.

  10. Synergy of licorice extract and pea protein hydrolysate for oxidative stability of soybean oil-in-water emulsions.

    PubMed

    Zhang, Xin; Xiong, Youling L; Chen, Jie; Zhou, Lirong

    2014-08-13

    Previously developed radical-scavenging pea protein hydrolysates (PPHs) prepared with Flavourzyme (Fla-PPH) and Protamex (Pro-PPH) were used as cosurfactants with Tween 20 to produce soybean oil-in-water (O/W) emulsions, and the suppression of lipid oxidation was investigated. Both PPHs significantly retarded oxidation (P < 0.05) of the emulsions when stored at 37 °C for 14 days. Electron microscopy revealed an interfacial peptidyl membrane around oil droplets, which afforded steric restrictions to oxidation initiators. When licorice extract (LE) was also used in emulsion preparation, a remarkable synergistic oxidation inhibition was observed with both PPHs. LE adsorbed onto oil droplets either directly or through associating with PPH to produce a thick and compact interfacial membrane enabling the defense against oxygen species. Liquiritin apioside, neolicuroside, glabrene, and 18β-glycyrrhetic acid were the predominant phenolic derivatives partitioning at the interface and most likely the major contributors to the notable synergistic antioxidant activity when coupled with PPHs. PMID:25058384

  11. 15N tracer studies of protein metabolism in low birth weight preterm infants: a comparison of 15N glycine and 15N yeast protein hydrolysate and of human milk- and formula-fed babies.

    PubMed

    Stack, T; Reeds, P J; Preston, T; Hay, S; Lloyd, D J; Aggett, P J

    1989-02-01

    Nitrogen flux and protein synthesis and degradation were estimated using a single oral bolus of 15N glycine or 15N yeast protein hydrolysate and measuring the 15N enrichment of urinary ammonia in five low birth wt infants fed a low birth wt formula and in six who were receiving their own mother's breast milk. Results derived from using 15N-glycine and 15N-yeast hydrolysate tracers in a randomized crossover study in 10 studies on seven infants showed, with one exception, higher turnover rates and more interindividual variation with the 15N yeast. Both tracers showed good reproducibility in two infants who had repeated studies. Although wt gain was similar in both groups, nitrogen intake and retention were greater (p less than 0.01) in the formula-fed group. Mean nitrogen turnover was similar in both groups, but there was a greater variance in the human milk-fed group which also had a greater nitrogen turnover/U absorbed nitrogen (p less than 0.025) and a lower excretion of nitrogen/U flux. PMID:2919131

  12. New cultive medium for bioconversion of C5 fraction from sugarcane bagasse using rice bran extract

    PubMed Central

    da Silva, Debora Danielle Virginio; Cândido, Elisangela de Jesus; de Arruda, Priscila Vaz; da Silva, Silvio Silvério; Felipe, Maria das Graças de Almeida

    2014-01-01

    The use of hemicellulosic hydrolysates in bioprocesses requires supplementation as to ensure the best fermentative performance of microorganisms. However, in light of conflicting data in the literature, it is necessary to establish an inexpensive and applicable medium for the development of bioprocesses. This paper evaluates the fermentative performance of Scheffersomyces (Pichia) stipitis and Candida guilliermondii growth in sugarcane bagasse hemicellulosic hydrolysate supplemented with different nitrogen sources including rice bran extract, an important by-product of agroindustry and source of vitamins and amino acids. Experiments were carried out with hydrolysate supplemented with rice bran extract and (NH4)2SO4; peptone and yeast extract; (NH4)2SO4, peptone and yeast extract and non-supplemented hydrolysate as a control. S. stipitis produced only ethanol, while C. guilliermondii produced xylitol as the main product and ethanol as by-product. Maximum ethanol production by S. stipitis was observed when sugarcane bagasse hemicellulosic hydrolysate was supplemented with (NH4)2SO4, peptone and yeast extract. Differently, the maximum xylitol formation by C. guilliermondii was obtained by employing hydrolysate supplemented with (NH4)2SO4 and rice bran extract. Together, these findings indicate that: a) for both yeasts (NH4)2SO4 was required as an inorganic nitrogen source to supplement sugarcane bagasse hydrolysate; b) for S. stipitis, sugarcane hemicellulosic hydrolysate must be supplemented with peptone and yeast extract as organic nitrogen source; and: c) for C. guilliermondii, it must be supplemented with rice bran extract. The present study designed a fermentation medium employing hemicellulosic hydrolysate and provides a basis for studies about value-added products as ethanol and xylitol from lignocellulosic materials. PMID:25763056

  13. Antibacterial and antioxidant properties of mixed linkage beta-oligosaccharides from extracted β-glucan hydrolysed by Penicillium occitanis EGL lichenase.

    PubMed

    Chaari, Fatma; Belghith-Fendri, Lilia; Zaouri-Ellouzi, Soumaya; Driss, Dorra; Blibech, Monia; Kallel, Fatma; Bouaziz, Fatma; Mehdi, Yosra; Ellouz-Chaabouni, Semia; Ghorbel, Raoudha

    2016-06-01

    The aim of this study was first to ascertain the chemical composition and the physicochemical properties of cereal extracted β-glucan from barley flour. Secondly, to assess the antioxidant properties and the antibacterial properties of extracted β-glucan hydrolysates. The proximate composition, FT-IR and scanning electron microscopy of extracted β-Glucan were studied. Hydrolysates from extracted β-glucan, obtained by lichenase EGL from Penicillium occitanis, were a mixed linkage beta-oligosaccharides (MLBO) of trisaccharides and tetrasaccharides. MLBO showed a DPPH radical scavenger with IC50 about 1.8 ± 0.01 mg/mL whereas the IC50 of extracted β-glucan was about 5 ± 0.01 mg/mL. MLBO showed a high antioxidative capacity (175 μmol/mL α-tocopherol equivalents) at 5 mg/mL. The antimicrobial activity was confirmed against all tested bacteria especially at 20 mg/mL of MLBO while no inhibition was observed for all the strains used after the addition of either EGL or extracted β-glucan. PMID:26165546

  14. A strain of Meyerozyma guilliermondii isolated from sugarcane juice is able to grow and ferment pentoses in synthetic and bagasse hydrolysate media.

    PubMed

    Martini, Cristina; Tauk-Tornisielo, Sâmia Maria; Codato, Carolina Brito; Bastos, Reinaldo Gaspar; Ceccato-Antonini, Sandra Regina

    2016-05-01

    The search for new microbial strains that are able to withstand inhibitors released from hemicellulosic hydrolysis and are also still able to convert sugars in ethanol/xylitol is highly desirable. A yeast strain isolated from sugarcane juice and identified as Meyerozyma guilliermondii was evaluated for the ability to grow and ferment pentoses in synthetic media and in sugarcane bagasse hydrolysate. The yeast grew in xylose, arabinose and glucose at the same rate at an initial medium pH of 5.5. At pH 4.5, the yeast grew more slowly in arabinose. There was no sugar exhaustion within 60 h. At higher xylose concentrations with a higher initial cell concentration, sugar was exhausted within 96 h at pH 4.5. An increase of 350 % in biomass was obtained in detoxified hydrolysates, whereas supplementation with 3 g/L yeast extract increased biomass production by approximately 40 %. Ethanol and xylitol were produced more significantly in supplemented hydrolysates regardless of detoxification. Xylose consumption was enhanced in supplemented hydrolysates and arabinose was consumed only when xylose and glucose were no longer available. Supplementation had a greater impact on ethanol yield and productivity than detoxification; however, the product yields obtained in the present study are still much lower when compared to other yeast species in bagasse hydrolysate. By the other hand, the fermentation of both xylose and arabinose and capability of withstanding inhibitors are important characteristics of the strain assayed. PMID:27038950

  15. Yeast extract stimulates production of glycolipid biosurfactants, mannosylerythritol lipids, by Pseudozyma hubeiensis SY62.

    PubMed

    Konishi, Masaaki; Nagahama, Takahiko; Fukuoka, Tokuma; Morita, Tomotake; Imura, Tomohiro; Kitamoto, Dai; Hatada, Yuji

    2011-06-01

    We improved the culture conditions for a biosurfactant producing yeast, Pseudozyma hubeiensis SY62. We found that yeast extract greatly stimulates MEL production. Furthermore, we demonstrated a highly efficient production of MELs in the improved medium by fed-batch cultivation. The final concentration of MELs reached 129 ± 8.2g/l for one week. PMID:21393057

  16. Enumeration and rapid identification of yeasts during extraction processes of extra virgin olive oil in Tuscany.

    PubMed

    Mari, Eleonora; Guerrini, Simona; Granchi, Lisa; Vincenzini, Massimo

    2016-06-01

    The aim of this study was to evaluate the occurrence of yeast populations during different olive oil extraction processes, carried out in three consecutive years in Tuscany (Italy), by analysing crushed pastes, kneaded pastes, oil from decanter and pomaces. The results showed yeast concentrations ranging between 10(3) and 10(5) CFU/g or per mL. Seventeen dominant yeast species were identified by random amplified polymorphic DNA with primer M13 and their identification was confirmed by restriction fragments length polymorphism of ribosomal internal transcribed spacer and sequencing rRNA genes. The isolation frequencies of each species in the collected samples pointed out that the occurrence of the various yeast species in olive oil extraction process was dependent not only on the yeasts contaminating the olives but also on the yeasts colonizing the plant for oil extraction. In fact, eleven dominant yeast species were detected from the washed olives, but only three of them were also found in oil samples at significant isolation frequency. On the contrary, the most abundant species in oil samples, Yamadazyma terventina, did not occur in washed olive samples. These findings suggest a phenomenon of contamination of the plant for oil extraction that selects some yeast species that could affect the quality of olive oil. PMID:27116959

  17. Acidifying and yeast extract in diets for adults cats.

    PubMed

    Ogoshi, Rosana C S; Zangeronimo, Márcio G; Dos Reis, Jéssica S; França, Janine; Santos, João P F; Pires, Carolina P; Chizzotti, Ana F; Costa, Adriano C; Ferreira, Lívia G; Saad, Flávia M O B

    2014-05-01

    This study evaluated the effects of adding an acidifying agent based on phosphoric acid (A), a yeast extract from a specific strain (Saccharomyces cerevisiae) (Y) and the combination of these two additives in food for adult cats. A test was conducted with 24 animals (mean 3.5 years old), mixed breed, weighing 3.72 ± 0.74 kg, kept in individual metabolic cages and distributed in a completely randomized design with a 2 × 2 factorial design (with or without A 0.6% of dry matter, with or without Y 1.5% of dry matter) totalling four treatments and six replicates of each condition. The experimental period was 15 days. The A or the Y reduced (P< 0.01) the dry matter intake, but the effect was not observed when they were associated. The association improved (P<0.05) the digestibility of dry matter and ashes. The A reduced urine pH (P=0.05) regardless of the presence of the Y. There was no effect (P>0.09) on other parameters evaluated. Results of this study show that the isolated use of 0.6% A or 1.5% Y in diets for cats is not recommended. However, the association of these two additives was beneficial in increasing nutrient digestibility. PMID:24450338

  18. Polypeptide nature of growth requirement in yeast extract for Thermoplasma acidophilum.

    PubMed Central

    Smith, P F; Langworthy, T A; Smith, M R

    1975-01-01

    The active component(s) in yeast extract required by Thermoplasma acidophilum for growth is polypeptide in nature. A fraction from yeast extract was isolated and partially characterized as one or more peptides of molecular weight about 1,000 containing 8 to 10 amino acids. Although it was composed largely of basic and dicarboxylic amino acids, only one amino group per molecule was free. The polypeptide(s) appeared to bind avidly to cations. No other organic compounds except glucose were needed by Thermoplasma. Among several hundred known compounds tested, only glutathione plus Fe2+ or Fe3+, clostridial ferredoxin, and spinach ferredoxin elicited any growth response. PMID:1102535

  19. Feather keratin hydrolysates obtained from microbial keratinases: effect on hair fiber

    PubMed Central

    2013-01-01

    Background Hair is composed mainly of keratin protein and a small amount of lipid. Protein hydrolysates, in particular those with low molecular weight distribution have been known to protect hair against chemical and environmental damage. Many types of protein hydrolysates from plants and animals have been used in hair and personal care such as keratin hydrolysates obtained from nails, horns and wool. Most of these hydrolysates are obtained by chemical hydrolysis and hydrothermal methods, but recently hydrolyzed hair keratin, feather keratin peptides, and feather meal peptides have been obtained by enzymatic hydrolysis using Bacillus spp in submerged fermentation. Results Keratin peptides were obtained by enzymatic hydrolysis of keratinases using Bacillus subtilis AMR. The microorganism was grown on a feather medium, pH 8.0 (1% feathers) and supplemented with 0.01% of yeast extract, for 5 days, at 28°C with agitation. The supernatant containing the hydrolysates was colleted by centrifugation and ultra filtered in an AMICON system using nano–membranes (Millipore – YC05). The Proteins and peptides were analyzed using HPTLC and MALDI-TOF-MS. Commercial preparations of keratin hydrolysates were used as a comparative standard. After five days the feather had been degraded (90-95%) by the peptidases and keratinases of the microorganism. MALDI-TOF mass spectrometry showed multiple peaks that correspond to peptides in the range of 800 to 1079 Daltons and the commercial hydrolysate was in the range of 900 to 1400 Da. HPTLC showed lower molecular mass peptides and amino acids in the enzymatic hydrolysate when compared with the commercial hydrolysate . A mild shampoo and a rinse off conditioner were formulated with the enzymatic hydrolysate and applied to hair fibers to evaluate the hydration, with and without heat, using a Corneometer® CM 825. The hydration was more efficient with heat, suggesting a more complete incorporation of hydrolysates into the fibers. Scanning Electron Microscopy showed deposits of organic matter in the junction of the cuticles that probably collaborates to the sealing of the cuticles, increasing the brightness and softness. Conclusions These results show that the enzymatic method to produce keratin peptides for hair care products is an attractive and eco- friendly method with a great potential in the cosmetic industry. PMID:23414102

  20. Use of Non-Conventional Cell Disruption Method for Extraction of Proteins from Black Yeasts

    PubMed Central

    Čolnik, Maja; Primožič, Mateja; Knez, Željko; Leitgeb, Maja

    2016-01-01

    The influence of pressure and treatment time on cells disruption of different black yeasts and on activities of extracted proteins using supercritical carbon dioxide process was studied. The cells of three different black yeasts Phaeotheca triangularis, Trimatostroma salinum, and Wallemia ichthyophaga were exposed to supercritical carbon dioxide (SC CO2) by varying pressure at fixed temperature (35°C). The black yeasts cell walls were disrupted, and the content of the cells was spilled into the liquid medium. The impact of SC CO2 conditions on secretion of enzymes and proteins from black yeast cells suspension was studied. The residual activity of the enzymes cellulase, β-glucosidase, α-amylase, and protease was studied by enzymatic assay. The viability of black yeast cells was determined by measuring the optical density of the cell suspension at 600 nm. The total protein concentration in the suspension was determined on UV–Vis spectrophotometer at 595 nm. The release of intracellular and extracellular products from black yeast cells was achieved. Also, the observation by an environmental scanning electron microscopy shows major morphological changes with SC CO2-treated cells. The advantages of the proposed method are in a simple use, which is also possible for heat-sensitive materials on one hand and on the other hand integration of the extraction of enzymes and their use in biocatalytical reactions. PMID:27148527

  1. Yeast, beef and pork extracts counteract Clostridium difficile toxin A enterotoxicity.

    PubMed

    Duncan, Peter I; Fotopoulos, Grigorios; Pasche, Elisabeth; Porta, Nadine; Masserey Elmelegy, Isabelle; Sanchez-Garcia, Jose-Luis; Bergonzelli, Gabriela E; Corthésy-Theulaz, Irène

    2009-06-01

    Clostridium difficile is responsible for a large proportion of nosocomial cases of antibiotic-associated diarrhoea and pseudomembranous colitis. The present study provides evidence that yeast, beef and pork extracts, ingredients commonly used to grow bacteria, can counteract C. difficile toxin A enterotoxicity in vitro and in vivo. In model intestinal epithelial cells the individual extracts could prevent the toxin A-induced decrease in epithelial barrier function and partially prevented actin disaggregation and cell rounding. Mice with ad libitum access to individual extracts for 1 week had almost complete reduction in toxin A-induced fluid secretion in intestinal loops. Concomitantly, the toxin A-induced expression of the essential proinflammatory mediator Cox-2 was normalized. Moreover this protective effect was also seen when mice received only two doses of extract by intragastric gavage within 1 week. These results show that yeast, beef and pork extracts have the potential to counteract the intestinal pathogenesis triggered by C. difficile toxin A. PMID:19416358

  2. Bacterial clearance, heterophil function, and hematological parameters of transport stressed turkey poults supplemented with dietary yeast extract

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Yeast extracts contain biological response modifiers that may be useful as alternatives to antibiotics for controlling pathogens in poultry production and mitigating the deleterious effects of production stressors. A standardized yeast extract feed supplement, Alphamune (YE), was added to turkey po...

  3. Gastrointestinal Maturation is Accelerated in Turkey Poults Supplemented with a Mannan-Oligosaccharide Yeast Extract (Alphamune)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Alphamune™, a yeast extract antibiotic alternative, has been shown to stimulate the immune system, increase body weight in pigs, and reduce Salmonella colonization in chickens. The influence of Alphamune™ on gastrointestinal tract development has not been reported. Two trials were conducted to evalu...

  4. Effects of dietary yeast extract on turkey stress response and heterophil oxidative burst activity

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Effective nutritional approaches to counteract the negative effects of stress would both improve human health and provide food animal producers with useful alternatives to antibiotics. In this study, turkeys were fed a standard diet or the same diet supplemented with yeast extract (Alphamune™, YE), ...

  5. GASTROINTESTINAL MATURATION IS ACCELERATED IN TURKEY POULTS SUPPLEMENTED WITH A MANNAN-OLIGOSACCHARIDE YEAST EXTRACT (ALPHAMUNE)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Alphamune is a yeast extract antibiotic alternative that has been shown to stimulate the immune system and increase BW in pigs. The influence of Alphamune on gastrointestinal tract (GIT) development of turkey poults has not been reported. Two trials were conducted to evaluate the effects of Alphamun...

  6. Growth Characteristics and Physiological Functionality of Yeasts in Pear Marc Extracts

    PubMed Central

    Jang, In-Taek; Kang, Min-Gu; Na, Kwang-Chul

    2011-01-01

    Kluyveromyces fragilis KCTC 7260 and Saccharomyces cerevisiae KCTC 7904, which both grew well in pear marc extract, were selected and their growth profiles and physiological functionalities were determined. Both of the selected yeasts established maximal growth by 20 hr of cultivation at 30℃ in pear marc extract. The cell-free extracts showed high antihypertensive angiotensin I-converting enzyme inhibitory activity of 68.9% and 52.1%, respectively. The extracts also displayed 9.2 U/mL and 12.0 U/mL of protease activity, respectively. PMID:22783099

  7. A single protocol for extraction of gDNA from bacteria and yeast.

    PubMed

    Vingataramin, Laurie; Frost, Eric H

    2015-03-01

    Guanidine thiocyanate breakage of microorganisms has been the standard initial step in genomic DNA (gDNA) extraction of microbial DNA for two decades, despite the requirement for pretreatments to extract DNA from microorganisms other than Gram-negative bacteria. We report a quick and low-cost gDNA extraction protocol called EtNa that is efficient for bacteria and yeast over a broad range of concentrations. EtNa is based on a hot alkaline ethanol lysis. The solution can be immediately centrifuged to yield a crude gDNA extract suitable for PCR, or it can be directly applied to a silica column for purification. PMID:25757544

  8. Evidence for channeling of intermediates in the oxidative pentose phosphate pathway by soybean and pea nodule extracts, yeast extracts, and purified yeast enzymes.

    PubMed

    Debnam, P M; Shearer, G; Blackwood, L; Kohl, D H

    1997-06-01

    Evidence is presented that intermediates of the oxidative pentose phosphate pathway (OPPP) are channeled from one pathway enzyme to the next. CO2 produced from [1-14C]glucose in the presence of unlabelled pathway intermediates contained much more radioactivity than predicted by a model in which pathway-produced intermediates are in equilibrium with identical molecules in the bulk phase. This was the case whether glucose 6-phosphate (Glc6P), 6-phosphogluconolactone, or 6-phosphogluconate was added. Assumptions involved in calculating the amount of 14CO2 predicted for free mixing of 14C-labelled and unlabelled intermediates are discussed, together with the following results. (a) 14CO2 production by pea nodules in the presence of 3 mM 6-phosphogluconate was higher than in its absence. (b) Apparent channeling of intermediates was much higher for purified yeast enzymes than for yeast extract. (c) 6-Phosphogluconate and 6-phosphogluconolactone were channeled between yeast Glc6P dehydrogenase and 6-phosphogluconate dehydrogenase despite the absence of 6-phosphogluconolactonase in the purified yeast enzyme mixture. (d) When purified yeast hexokinase was physically separated from Glc6P dehydrogenase and 6-phosphogluconate dehydrogenase by a dialysis membrane, there was no apparent channeling. (e) Poly(ethylene glycol), high salt and detergents had little effect on apparent channeling of OPPP intermediates, which is consistent with a stable complex of enzymes. On the other hand, density gradient centrifugation experiments suggested a more transient interaction between the enzymes. Taken together, the results support channeling of OPPP pathway intermediates. PMID:9208916

  9. A rapid and simple method for DNA extraction from yeasts and fungi isolated from Agave fourcroydes.

    PubMed

    Tapia-Tussell, Raul; Lappe, Patricia; Ulloa, Miguel; Quijano-Ramayo, Andrés; Cáceres-Farfán, Mirbella; Larqué-Saavedra, Alfonso; Perez-Brito, Daisy

    2006-05-01

    A simple and easy protocol for extracting high-quality DNA from different yeast and filamentous fungal species is described. This method involves two important steps: first, the disruption of cell walls by mechanical means and freezing; and second, the extraction, isolation, and precipitation of genomic DNA. The absorbance ratios (A(260)/A(280)) obtained ranged from 1.6 to 2.0. The main objective of this procedure is to extract pure DNA from yeast and filamentous fungi, including those with high contents of proteins, polysaccharides, and other complex compounds in their cell walls. The yield and quality of the DNAs obtained were suitable for micro/minisatellite primer-polymerase chain reaction (MSP-PCR) fingerprinting as well as for the sequence of the D1/D2 domain of the 26S rDNA. PMID:16691008

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

    PubMed Central

    2013-01-01

    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

  11. Unveiling the potential of novel yeast protein extracts in white wines clarification and stabilization

    PubMed Central

    Fernandes, Joana P.; Neto, Rodrigo; Centeno, Filipe; De Fátima Teixeira, Maria; Gomes, Ana Catarina

    2015-01-01

    Fining agents derived from animal and mineral sources are widely used to clarify and stabilize white wines. Nevertheless, health and environmental problems are being raised, concerning the allergenic and environmental impact of some of those fining products. In this study, our aim is to validate the potential of yeast protein extracts, obtained from an alternative and safe source, naturally present in wine: oenological yeasts. Three untreated white wines were used in this work in order to evaluate the impact of these novel yeast protein extracts (YPE) in terms of the wine clarification and stabilization improvement. Two separated fining trials were thus conducted at laboratory scale and the yeast alternatives were compared with reference fining agents, obtained from mineral, animal and vegetable origins. Our results indicate that YPE were capable to promote (i) brilliance/color improvement, (ii) turbidity reduction (76–89% comparing with the untreated wines), and (iii) production of compact and homogeneous lees (44% smaller volume than obtained with bentonite). Additionally, after submitting wines to natural and forced oxidations, YPE treatments revealed (iv) different forms of colloidal stabilization, by presenting comparable or superior effects when particularly compared to casein. Altogether, this study reveals that YPE represent a promising alternative for white wine fining, since they are resultant from a natural and more sustainable origin, at present not regarded as potential allergenic according to Regulation (EC) No. 1169/2011. PMID:25853122

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

    PubMed

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

    2014-11-01

    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

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

    SciTech Connect

    Holmes, R.L.

    1982-04-01

    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.

  14. Methyl jasmonate and yeast extract stimulate mitragynine production in Mitragyna speciosa (Roxb.) Korth. shoot culture.

    PubMed

    Wungsintaweekul, Juraithip; Choo-Malee, Jutarat; Charoonratana, Tossaton; Keawpradub, Niwat

    2012-10-01

    Mitragynine is a pharmacologically-active terpenoid indole alkaloid found in Mitragyna speciosa leaves. Treatment with methyl jasmonate (10 μM) for 24 h and yeast extract (0.1 mg/ml) for 12 h were the optimum conditions of elicitation of mitragynine accumulation in a M. speciosa shoot culture. The former elicitor gave 0.11 mg mitragynine/g dry wt. Tryptophan decarboxylase and strictosidine synthase mRNA levels were enhanced in accordance with mitragynine accumulation. PMID:22714271

  15. Chlorhexidine: beta-cyclodextrin inhibits yeast growth by extraction of ergosterol

    PubMed Central

    Teixeira, K. I. R.; Araújo, P. V.; Sinisterra, R. D.; Cortés, M. E.

    2012-01-01

    Chlorhexidine (Cx) augmented with beta-cyclodextrin (β-cd) inclusion compounds, termed Cx:β-cd complexes, have been developed for use as antiseptic agents. The aim of this study was to examine the interactions of Cx:β-cd complexes, prepared at different molecular ratios, with sterol and yeast membranes. The Minimal Inhibitory Concentration (MIC) against the yeast Candida albicans (C.a.) was determined for each complex; the MICs were found to range from 0.5 to 2 μg/mL. To confirm the MIC data, quantitative analysis of viable cells was performed using trypan blue staining. Mechanistic characterization of the interactions that the Cx:β-cd complexes have with the yeast membrane and assessment of membrane morphology following exposure to Cx:β-cd complexes were performed using Sterol Quantification Method analysis (SQM) and scanning electron microscopy (SEM). SQM revealed that sterol extraction increased with increasing β-cd concentrations (1.71 ×103; 1.4 ×103; 3.45 ×103, and 3.74 ×103 CFU for 1:1, 1:2, 1:3, and 1:4, respectively), likely as a consequence of membrane ergosterol solubilization. SEM images demonstrated that cell membrane damage is a visible and significant mechanism that contributes to the antimicrobial effects of Cx:β-cd complexes. Cell disorganization increased significantly as the proportion of β-cyclodextrin present in the complex increased. Morphology of cells exposed to complexes with 1:3 and 1:4 molar ratios of Cx:β-cd were observed to have large aggregates mixed with yeast remains, representing more membrane disruption than that observed in cells treated with Cx alone. In conclusion, nanoaggregates of Cx:β-cd complexes block yeast growth via ergosterol extraction, permeabilizing the membrane by creating cluster-like structures within the cell membrane, possibly due to high amounts of hydrogen bonding. PMID:24031894

  16. Antioxidant activities and selected characteristics of gelatin hydrolysates from seabass (Lates calcarifer) skin as affected by production processes.

    PubMed

    Sae-Leaw, Thanasak; O'Callaghan, Yvonne C; Benjakul, Soottawat; O'Brien, Nora M

    2016-01-01

    Antioxidant activities and selected characteristics of gelatin hydrolysates from seabass skin as affected by production processes were investigated. Hydrolysates were prepared using different processes, including hydrolysis during and after gelatin extraction. Samples hydrolysed during gelatin extraction showed a higher degree of hydrolysis (DH) and yield compared with those hydrolysed after gelatin extraction (p < 0.05). All hydrolysates had a creamy yellowish colour. A lower abundance of volatile compounds was found in the hydrolysates produced during gelatin extraction, in comparison with those obtained after gelatin extraction. Hydrolysates prepared during gelatin extraction had higher 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity, ferric reducing antioxidative power (FRAP) and ferrous ion chelating activity (p < 0.05). Following a simulated in vitro gastrointestinal digestion, the DPPH radical scavenging activity and FRAP of the hydrolysates was retained, whilst ferrous ion chelating activity increased. The most appropriate conditions for the generation of antioxidant hydrolysates from seabass skin were identified. PMID:26787942

  17. Effects of temperature and substrate concentration on lipid production by Chlorella vulgaris from enzymatic hydrolysates of lipid-extracted microalgal biomass residues (LMBRs).

    PubMed

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

    2014-10-01

    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

  18. Mild alkali-pretreatment effectively extracts guaiacyl-rich lignin for high lignocellulose digestibility coupled with largely diminishing yeast fermentation inhibitors in Miscanthus.

    PubMed

    Li, Ming; Si, Shengli; Hao, Bo; Zha, Yi; Wan, Can; Hong, Shufen; Kang, Yongbo; Jia, Jun; Zhang, Jing; Li, Meng; Zhao, Chunqiao; Tu, Yuanyuan; Zhou, Shiguang; Peng, Liangcai

    2014-10-01

    In this study, various alkali-pretreated lignocellulose enzymatic hydrolyses were evaluated by using three standard pairs of Miscanthus accessions that showed three distinct monolignol (G, S, H) compositions. Mfl26 samples with elevated G-levels exhibited significantly increased hexose yields of up to 1.61-fold compared to paired samples derived from enzymatic hydrolysis, whereas Msa29 samples with high H-levels displayed increased hexose yields of only up to 1.32-fold. In contrast, Mfl30 samples with elevated S-levels showed reduced hexose yields compared to the paired sample of 0.89-0.98 folds at p<0.01. Notably, only the G-rich biomass samples exhibited complete enzymatic hydrolysis under 4% NaOH pretreatment. Furthermore, the G-rich samples showed more effective extraction of lignin-hemicellulose complexes than the S- and H-rich samples upon NaOH pretreatment, resulting in large removal of lignin inhibitors to yeast fermentation. Therefore, this study proposes an optimal approach for minor genetic lignin modification towards cost-effective biomass process in Miscanthus. PMID:25079210

  19. Extraction of brewer's yeasts using different methods of cell disruption for practical biodiesel production.

    PubMed

    Řezanka, Tomáš; Matoulková, Dagmar; Kolouchová, Irena; Masák, Jan; Viden, Ivan; Sigler, Karel

    2015-05-01

    The methods of preparation of fatty acids from brewer's yeast and its use in production of biofuels and in different branches of industry are described. Isolation of fatty acids from cell lipids includes cell disintegration (e.g., with liquid nitrogen, KOH, NaOH, petroleum ether, nitrogenous basic compounds, etc.) and subsequent processing of extracted lipids, including analysis of fatty acid and computing of biodiesel properties such as viscosity, density, cloud point, and cetane number. Methyl esters obtained from brewer's waste yeast are well suited for the production of biodiesel. All 49 samples (7 breweries and 7 methods) meet the requirements for biodiesel quality in both the composition of fatty acids and the properties of the biofuel required by the US and EU standards. PMID:25394535

  20. A Yeast Metabolite Extraction Protocol Optimised for Time-Series Analyses

    PubMed Central

    Sasidharan, Kalesh; Soga, Tomoyoshi; Tomita, Masaru; Murray, Douglas B.

    2012-01-01

    There is an increasing call for the absolute quantification of time-resolved metabolite data. However, a number of technical issues exist, such as metabolites being modified/degraded either chemically or enzymatically during the extraction process. Additionally, capillary electrophoresis mass spectrometry (CE-MS) is incompatible with high salt concentrations often used in extraction protocols. In microbial systems, metabolite yield is influenced by the extraction protocol used and the cell disruption rate. Here we present a method that rapidly quenches metabolism using dry-ice ethanol bath and methanol N-ethylmaleimide solution (thus stabilising thiols), disrupts cells efficiently using bead-beating and avoids artefacts created by live-cell pelleting. Rapid sample processing minimised metabolite leaching. Cell weight, number and size distribution was used to calculate metabolites to an attomol/cell level. We apply this method to samples obtained from the respiratory oscillation that occurs when yeast are grown continuously. PMID:22952947

  1. Effect of scenedesmus acuminatus green algae extracts on the development of Candida lipolytic yeast in gas condensate-containing media

    NASA Technical Reports Server (NTRS)

    Bilmes, B. I.; Kasymova, G. A.; Runov, V. I.; Karavayeva, N. N.

    1980-01-01

    Data are given of a comparative study of the growth and development as well as the characteristics of the biomass of the C. Lipolytica yeast according to the content of raw protein, protein, lipids, vitamins in the B group, and residual hydrocarbons during growth in media with de-aromatized gas-condensate FNZ as the carbon source with aqueous and alcohol extracts of S. acuminatus as the biostimulants. It is shown that the decoction and aqueous extract of green algae has the most intensive stimulating effect on the yeast growth. When a decoction of algae is added to the medium, the content of residual hydrocarbons in the biomass of C. lipolytica yeast is reduced by 4%; the quantity of protein, lipids, thamine and inositol with replacement of the yeast autolysate by the decoction of algae is altered little.

  2. Evaluation of corncob hemicellulosic hydrolysate for xylitol production by adapted strain of Candida tropicalis.

    PubMed

    Misra, Swati; Raghuwanshi, Shailendra; Saxena, R K

    2013-02-15

    A maximum xylose extraction of 21.98 g/L was obtained in hydrolysate with a solid to liquid ratio of 1:8 (w/v) at 1% H(2)SO(4) and treated for 30 min. The optimized and treated corncob hemicellulosic hydrolysate medium supplemented with (g/L) yeast extract 5.0, KH(2)PO(4) 2.0, MgSO(4)7H(2)O 0.3 and methanol 10 mL whose pH was adjusted to 4.5 acts as production medium. Under this condition; the adapted strain of C. tropicalis resulted in 1.22-fold increase in xylitol yield and 1.70-fold enhancement in volumetric productivity was obtained as compared to parent strain of C. tropicalis. On concentrating the hydrolysate under vacuum using rotavapor proves to be efficient in terms of improved xylitol yield and productivity over microwave assisted concentration using adapted strain of C. tropicalis. The immobilized cells of C. tropicalis resulted in more than 70% efficiency up to third cycle. The xylitol production could be scaled up to 10 L fermentor. PMID:23399194

  3. Assessment of protease activity in hydrolysed extracts from SSF of hair waste by and indigenous consortium of microorganisms.

    PubMed

    Yazid, Noraziah Abu; Barrena, Raquel; Sánchez, Antoni

    2016-03-01

    Hair wastes from the tannery industry were assessed for its suitability as substrates for protease production by solid-state fermentation (SSF) using a pilot-batch mode operation and anaerobically digested sludge as co-substrate. Maximum protease activity (52,230±1601Ug(-1)DM) was observed at the 14th day of SSF. Single step purification resulted in 2 fold purification with 74% of recovery by ultrafiltration with 10kDa cut-off. The recovered enzyme was stable at a temperature of 30°C and pH 11; optimal conditions that were determined by a central composite full factorial experimental design. The enzyme activity was inhibited by phenylmethylsulfonyl fluoride, which indicates that it belongs to serine protease group. The remaining solid material after protease extraction could be easily stabilized to obtain a final good quality compost-like material as the final dynamic respiration index was lower than 1gO2kg(-1)OMh(-1). The lyophilized recovered enzymes were a good alternative in the process of cowhides dehairing with respect to the current chemical treatment, avoiding the production of solid wastes and highly polluted wastewaters. In conclusion, the entire process can be considered a low-cost sustainable technology for the dehairing process, closing the organic matter cycle in the form of value added product and a compost-like material from a waste. PMID:26856443

  4. Purification and full characterisation of citreoviridin produced by Penicillium citreonigrum in yeast extract sucrose (YES) medium.

    PubMed

    da Rocha, Mariana Wagner; Resck, Inês Sabioni; Caldas, Eloisa Dutra

    2015-01-01

    The mycotoxin citreoviridin has been associated with the 'yellow rice' disease, which caused cardiac beriberi in Japan. In Brazil, the consumption of contaminated rice was suspected to be involved in a recent beriberi outbreak. In this work, citreoviridin was produced by Penicillium citreonigrum, cultivated in 500 ml yeast extract sucrose (YES) liquid medium for 8 days at 25ºC, and the toxin extracted with chloroform from the liquid medium and the mycelium. A total of 15.3 g of crude extract was obtained from 48 culture flasks, with an estimated citreoviridin contend of 5.54 g, 74.3% being present in the mycelia. Semi-preparative HPLC of the crude extract yielded 27.1% citreoviridin. The HPLC-purified citreoviridin fraction was fully characterised by UV/VIS, FT-IR, (1)H- and (13)C-NMR, LC-MS/MS and LC-MSD TOF, and purity confirmed by gravimetric analysis. Isocitreoviridin was also produced by P. citreonigrum, accounting for about 10% of the citreoviridin present in the crude extract, most transformed into citreoviridin after 10 months under freezing conditions protected from light. Citreoviridin was shown to be stable under the same conditions, although it can suffer isomerisation after a longer storage period. Isomerisation is a potential source of variability in toxicological studies and purity of the material should be checked before study initiation. PMID:25190053

  5. [Effects of 33% grapefruit extract on the growth of the yeast--like fungi, dermatopytes and moulds].

    PubMed

    Krajewska-Kułak, E; Lukaszuk, C; Niczyporuk, W

    2001-01-01

    Grapefruit seed extract was discovered by Jacob Harich an american immunologist in 1980. Assessment of the influence of grapefruit extract on the yeast-like fungi strains--Candida albicans growth. Material used in this investigation was ATCC test Candida albicans strains no 10231, 200 of Candida albicans strains, 5 of Candida sp. strains isolated from patients with candidiasis symptoms from different ontocenosis and 12 of dermatophytes and moulds isolated from patients. The susceptibility of the Candida was determined by serial dilution method. It seems that 33% grapefruit extract exert a potent antifungal activity against the yeast like fungi strains and had low activity against dermatophytes and moulds. Further studies in vitro and in vivo on greater number of the yeast-like fungi strains and other fungi species are needed. PMID:16886437

  6. Photocatalytic activity of biogenic silver nanoparticles synthesized using yeast ( Saccharomyces cerevisiae) extract

    NASA Astrophysics Data System (ADS)

    Roy, Kaushik; Sarkar, C. K.; Ghosh, C. K.

    2015-11-01

    Synthesis of metallic and semiconductor nanoparticles through physical and chemical route is quiet common but biological synthesis procedures are gaining momentum due to their simplicity, cost-effectivity and eco-friendliness. Here, we report green synthesis of silver nanoparticles from aqueous solution of silver salts using yeast ( Saccharomyces cerevisiae) extract. The nanoparticles formation was gradually investigated by UV-Vis spectrometer. X-ray diffraction analysis was done to identify different phases of biosynthesized Ag nanoparticles. Transmission electron microscopy was performed to study the particle size and morphology of silver nanoparticles. Fourier transform infrared spectroscopy of the nanoparticles was performed to study the role of biomolecules capped on the surface of Ag nanoparticles during interaction. Photocatalytic activity of these biosynthesized nanoparticles was studied using an organic dye, methylene blue under solar irradiation and these nanoparticles showed efficacy in degrading the dye within a few hours of exposure.

  7. Yeast Extract: Sucrose Ratio Effects on Egg Load, Survival, and Mortality Caused by GF-120 in Western Cherry Fruit Fly

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Extrinsic sources of nitrogen are needed by tephritid fruit flies for optimal nutrition. In this study, relationships between yeast extract diets containing 0, 0.109, 0.545, 1.09, 2.18, 3.27, and 5.45% nitrogen (N) and diet intake, survival, egg production, and responses to spinosad bait in western...

  8. Effect of Yeast Extract and Vitamin B(12) on Ethanol Production from Cellulose by Clostridium thermocellum I-1-B.

    PubMed

    Sato, K; Goto, S; Yonemura, S; Sekine, K; Okuma, E; Takagi, Y; Hon-Nami, K; Saiki, T

    1992-02-01

    Addition to media of yeast extract, a vitamin mixture containing vitamin B(12), biotin, pyridoxamine, and p-aminobenzoic acid, or vitamin B(12) alone enhanced formation of ethanol but decreased lactate production in the fermentation of cellulose by Clostridium thermocellum I-1-B. A similar effect was not observed with C. thermocellum ATCC 27405 and JW20. PMID:16348657

  9. Effects of yeast extract and vitamin D on turkey mortality and cellulitis incidence in a transport stress model.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We evaluated yeast extract (YE) and vitamin D (VD) in turkeys treated with dexamethasone (Dex) at intervals designed to simulate transport stress during a 3 stage growout. YE but not VD decreased early mortality (P = 0.001) and mortality at wk 7 (P= 0.02) and wk 12 (P = 0.002) but not wk 16. Celluli...

  10. Simulation of the continuous fermentation of manioc hydrolysate

    SciTech Connect

    Bonomi, A.; Aboutboul, H.; Schmidell, W.

    1981-01-01

    The simulation of the continuous fermentation of manioc hydrolysate utilizing a yeast strain of Saccharomyces cerevisiae isolated from the commercial pressed yeast largely employed in Brazilian distilleries is described. The model used in the simulation is derived from batch experimental runs. In order to assess the economical competitiveness of the continuous fermentation, some additional concepts, such as cell recycle, and two fermentors connected in series with and without feed division of fresh substrate, are analyzed and compared.

  11. Use of yeast cell wall extract as a tool to reduce the impact of necrotic enteritis in broilers.

    PubMed

    M'Sadeq, Shawkat A; Wu, Shu-Biao; Choct, Mingan; Forder, Rebecca; Swick, Robert A

    2015-05-01

    The use of a yeast cell wall extract derived from Saccharomyces cerevisiae (Actigen(®)) has been proposed as an alternative to in-feed antibiotics. This experiment was conducted to investigate the efficacy of yeast cell extract as an alternative to zinc bacitracin or salinomycin using a necrotic enteritis challenge model. A feeding study was conducted using 480-day-old male Ross 308 chicks assigned to 48 floor pens. A 2 × 4 factorial arrangement of treatments was employed. The factors were: challenge (- or +) and feed additive (control, zinc bacitracin at 100/50 mg/kg, yeast cell wall extract at 400/800/200 mg/kg, or salinomycin at 60 mg/kg in starter, grower, and finisher, respectively). Diets based on wheat, sorghum, soybean meal, meat and bone meal, and canola meal were formulated according to the Ross 308 nutrient specifications. Birds were challenged using a previously established protocol (attenuated Eimeria spp oocysts) on d 9 and 10(8) to 10(9) Clostridium perfringens (type A strain EHE-NE18) on d 14 and 15). Challenged and unchallenged birds were partitioned to avoid cross contamination. Challenged birds had lower weight gain, feed intake and livability compared to unchallenged birds on d 24 and d 35 (P < 0.05). Birds given zinc bacitracin, yeast cell wall extract, or salinomycin had improved weight gain and livability when compared to control birds given no additives. Challenge × additive interactions were observed for feed intake and weight gain on d 24 and d 35 (P < 0.01). The additives all had a greater positive impact on feed intake, weight gain, and livability in challenged than unchallenged birds. All challenged birds showed higher necrotic enteritis lesion scores in the small intestine sections when compared to unchallenged birds (P < 0.01). Birds fed yeast cell wall extract exhibited increased villus height, decreased crypt depth, and increased villus:crypt ratio when challenged. Yeast cell wall extract, zinc bacitracin, and salinomycin were effective in preventing performance decline from necrotic enteritis in the current study. This study indicates that yeast cell wall extract has promise as a tool for controlling necrotic enteritis. PMID:25762162

  12. Fermentation performance and physiology of two strains of Saccharomyces cerevisiae during growth in high gravity spruce hydrolysate and spent sulphite liquor

    PubMed Central

    2014-01-01

    Background Lignocellulosic materials are a diverse group of substrates that are generally scarce in nutrients, which compromises the tolerance and fermentation performance of the fermenting organism. The problem is exacerbated by harsh pre-treatment, which introduces sugars and substances inhibitory to yeast metabolism. This study compares the fermentation behaviours of two yeast strains using different types of lignocellulosic substrates; high gravity dilute acid spruce hydrolysate (SH) and spent sulphite liquor (SSL), in the absence and presence of yeast extract. To this end, the fermentation performance, energy status and fermentation capacity of the strains were measured under different growth conditions. Results Nutrient supplementation with yeast extract increased sugar uptake, cell growth and ethanol production in all tested fermentation conditions, but had little or no effect on the energy status, irrespective of media. Nutrient-supplemented medium enhanced the fermentation capacity of harvested cells, indicating that cell viability and reusability was increased by nutrient addition. Conclusions Although both substrates belong to the lignocellulosic spruce hydrolysates, their differences offer specific challenges and the overall yields and productivities largely depend on choice of fermenting strain. PMID:24885359

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

    PubMed Central

    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

    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 γ-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

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

    PubMed

    Yeap, Swee Keong; Beh, Boon Kee; Kong, Joan; Ho, Wan Yong; Mohd Yusof, Hamidah; Mohamad, Nurul Elyani; Hussin, Aminuddin Bin; Jaganath, Indu Bala; Alitheen, Noorjahan Banu; Jamaluddin, Anisah; Long, Kamariah

    2014-01-01

    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 γ-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

  15. Zinc-containing yeast extract promotes nonrapid eye movement sleep in mice.

    PubMed

    Cherasse, Yoan; Saito, Hitomi; Nagata, Nanae; Aritake, Kosuke; Lazarus, Michael; Urade, Yoshihiro

    2015-10-01

    Zinc is an essential trace element for humans and animals, being located, among other places, in the synaptic vesicles of cortical glutamatergic neurons and hippocampal mossy fibers in the brain. Extracellular zinc has the potential to interact with and modulate many different synaptic targets, including glutamate and GABA receptors. Because of the central role of these neurotransmitters in brain activity, we examined in this study the sleep-promoting activity of zinc by monitoring locomotor activity and electroencephalogram after its administration to mice. Zinc-containing yeast extract (40 and 80 mg/kg) dose dependently increased the total amount of nonrapid eye movement sleep and decreased the locomotor activity. However, this preparation did not change the amount of rapid eye movement sleep or show any adverse effects such as rebound of insomnia during a period of 24 h following the induction of sleep; whereas the extracts containing other divalent cations (manganese, iron, and copper) did not decrease the locomotor activity. This is the first evidence that zinc can induce sleep. Our data open the way to new types of food supplements designed to improve sleep. PMID:26105624

  16. 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

    2013-01-01

    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

  17. SUMO expression shortens the lag phase of Saccharomyces cerevisiae yeast growth caused by complex interactive effects of major mixed fermentation inhibitors found in hot-compressed water-treated lignocellulosic hydrolysate.

    PubMed

    Jayakody, Lahiru N; Kadowaki, Masafumi; Tsuge, Keisuke; Horie, Kenta; Suzuki, Akihiro; Hayashi, Nobuyuki; Kitagaki, Hiroshi

    2015-01-01

    The complex inhibitory effects of inhibitors present in lignocellulose hydrolysate suppress the ethanol fermentation of Saccharomyces cerevisiae. Although the interactive inhibitory effects play important roles in the actual hydrolysate, few studies have investigated glycolaldehyde, the key inhibitor of hot-compressed water-treated lignocellulose hydrolysate. Given this challenge, we investigated the interactive effects of mixed fermentation inhibitors, including glycolaldehyde. First, we confirmed that glycolaldehyde was the most potent inhibitor in the hydrolysate and exerted interactive inhibitory effects in combination with major inhibitors. Next, through genome-wide analysis and megavariate data modeling, we identified SUMOylation as a novel potential mechanism to overcome the combinational inhibitory effects of fermentation inhibitors. Indeed, overall SUMOylation was increased and Pgk1, which produces an ATP molecule in glycolysis by substrate-level phosphorylation, was SUMOylated and degraded in response to glycolaldehyde. Augmenting the SUMO-dependent ubiquitin system in the ADH1-expressing strain significantly shortened the lag phase of growth, released cells from G2/M arrest, and improved energy status and glucose uptake in the inhibitor-containing medium. In summary, our study was the first to establish SUMOylation as a novel platform for regulating the lag phase caused by complex fermentation inhibitors. PMID:25359478

  18. The Effects of Mechanically Deboned Chicken Hydrolysates on the Characteristics of Imitation Crab Stick

    PubMed Central

    Jin, Sang-Keun; Hwang, Jin-Won; Moon, Sungsil; Choi, Yeung-Joon; Kim, Gap-Don; Jung, Eun-Young; Yang, Han-Sul

    2014-01-01

    The effects of adding mechanically deboned chicken (MDC) hydrolysates on the quality characteristics of imitation crab stick (ICS) during storage were investigated. ICS was prepared from Alaska Pollack, chicken breast surimi, and protein hydrolysates enzymatically extracted from MDC. ICS samples were divided into 4 groups: without protein hydrolysate (control), added with 0.5% protein hydrolysate (T1), added with 1.0% protein hydrolysate (T2), and added with 1.5% protein hydrolysate (T3). Results showed that crude protein content did not differ significantly among the ICS samples (p>0.05). ICS sample added with MDC hydrolysates had higher crude fat and ash content but lower moisture content than the control (p<0.05). Lightness was significantly lower in T2 and T3 than in the other groups at 0 and 4 wk of storage. Also, whiteness decreased in the groups contained MDC hydrolysates. Breaking force and jelly strength were higher in samples containing MDC hydrolysates compared to control samples (p<0.05). Additionally, saturated fatty acid contents were lower in the groups containing MDC hydrolysates than in control sample groups (p<0.05). Polyunsaturated fatty acid (PUFA) and essential fatty acids (EFA) were significantly higher in T2 and T3 than the control samples. In particular, all samples containing MDC hydrolysates had reduced thiobarbituric acid-reactive substances (TBARS) values at 4 wk. Free radical scavenging activity also was increased with addition of MDC hydrolysates. PMID:26760938

  19. The Effects of Mechanically Deboned Chicken Hydrolysates on the Characteristics of Imitation Crab Stick.

    PubMed

    Jin, Sang-Keun; Hwang, Jin-Won; Moon, Sungsil; Choi, Yeung-Joon; Kim, Gap-Don; Jung, Eun-Young; Yang, Han-Sul

    2014-01-01

    The effects of adding mechanically deboned chicken (MDC) hydrolysates on the quality characteristics of imitation crab stick (ICS) during storage were investigated. ICS was prepared from Alaska Pollack, chicken breast surimi, and protein hydrolysates enzymatically extracted from MDC. ICS samples were divided into 4 groups: without protein hydrolysate (control), added with 0.5% protein hydrolysate (T1), added with 1.0% protein hydrolysate (T2), and added with 1.5% protein hydrolysate (T3). Results showed that crude protein content did not differ significantly among the ICS samples (p>0.05). ICS sample added with MDC hydrolysates had higher crude fat and ash content but lower moisture content than the control (p<0.05). Lightness was significantly lower in T2 and T3 than in the other groups at 0 and 4 wk of storage. Also, whiteness decreased in the groups contained MDC hydrolysates. Breaking force and jelly strength were higher in samples containing MDC hydrolysates compared to control samples (p<0.05). Additionally, saturated fatty acid contents were lower in the groups containing MDC hydrolysates than in control sample groups (p<0.05). Polyunsaturated fatty acid (PUFA) and essential fatty acids (EFA) were significantly higher in T2 and T3 than the control samples. In particular, all samples containing MDC hydrolysates had reduced thiobarbituric acid-reactive substances (TBARS) values at 4 wk. Free radical scavenging activity also was increased with addition of MDC hydrolysates. PMID:26760938

  20. Investigations on hydrolytic activities from Stachybotrys microspora and their use as an alternative in yeast DNA extraction.

    PubMed

    Abdeljalil, Salma; Ben Hmad, Ines; Saibi, Walid; Amouri, Bahia; Maalej, Wiem; Kaaniche, Marwa; Koubaa, Aida; Gargouri, Ali

    2014-02-01

    Stachybotrys microspora is a filamentous fungus characterized by the secretion of multiple hydrolytic activities (cellulolytic and non-cellulolytic enzymes). The production of these biocatalysts was studied under submerged culture using glucose, cellulose, and wheat bran as carbon sources. Endoglucanases, pectinases, xylanases, β-glucanases, chitinases, and proteases were induced on cellulose-based medium and repressed on glucose in both strains with higher amounts produced by the mutant. β-glucosidases were roughly equally produced by both strains under glucose and cellulose conditions. The yield of chitinases, β-glucanases, and proteases produced by Stachybotrys strains was as much higher than the commercialized lysing enzyme called "zymolyase," currently used in yeast DNA extraction. In this context, we showed that S. microspora hydrolases can be successfully applied in the extraction of yeast DNA. PMID:24241970

  1. Preparation and characterization of yeast nuclear extracts for efficient RNA polymerase B (II)-dependent transcription in vitro.

    PubMed

    Verdier, J M; Stalder, R; Roberge, M; Amati, B; Sentenac, A; Gasser, S M

    1990-12-11

    We present a reproducible method for the preparation of nuclear extracts from the yeast Saccharomyces cerevisiae that support efficient RNA polymerase B (II)-dependent transcription. Extracts from both a crude nuclear fraction and Percoll-purified nuclei are highly active for site-specific initiation and transcription of a G-free cassette under the Adenovirus major late promoter. At optimal extract concentrations transcription is at least 5 times more efficient with the yeast extracts than with HeLa whole cell extracts. We show that the transcriptional activity is sensitive to alpha-amanitin and to depletion of factor(s) recognizing the TATA-box of the promoter. The in vitro reaction showed maximal activity after 45 min, was very sensitive to Cl-, but was not affected by high concentrations of potassium. We find that the efficiency of in vitro transcription in nuclear extracts is reproducibly high when spheroplasting is performed with a partially purified beta 1,3-glucanase (lyticase). Therefore a simplified method to isolate the lyticase from the supernatant of Oerskovia xanthineolytica is also presented. PMID:2263463

  2. Homogeneous pyruvate kinase isolated from yeast by two different methods is indistinguishable from pyruvate kinase in cell-free extract.

    PubMed

    Aust, A E; Suelter, C H

    1978-10-25

    In this report, we have compared homogeneous yeast (Saccharomyces cerevisiae) pyruvate kinase to enzyme from cell-free extracts in several different ways: 1) isoelectric focusing of cell-free extracts indicates one peak of pyruvate kinase activity whose isoelectric point is the same as that of the pure enzyme; 2) antibody prepared to the pure enzyme produces a single, fused precipitin line against enzyme in the cell-free extract and pure enzyme; 3) immunoelectrophoresis of cell-free extract produces one precipitin arc which has the same mobility as that of the pure enzyme; and 4) immunoprecipitation of the pure enzyme from cell-free extract with subsequent solubilization in 1% sodium dodecyl sulfate and electrophoresis on sodium dodecyl sulfate-polyacrylamide gels produces a single protein band attributable to pyruvate kinase which co-migrates with the purified enzyme. Within the limits of the sensitivity of the methods employed, we conclude that the homogeneous pyruvate kinase prepared from yeast lysed either by Manton-Gaulin homogenization (Aust, A., Yun, S.-L., and Suelter, C. (1975) Methods Enzymol. 42, 176-182) or by toluolysis (Yun, S.-L., Aust, A.E., and Suelter, C.H. (1977) J. Biol. Chem. 251, 124-128) is identical with pyruvate kinase in cell-free extract. PMID:100495

  3. Yeast Extract and Silver Nitrate Induce the Expression of Phenylpropanoid Biosynthetic Genes and Induce the Accumulation of Rosmarinic Acid in Agastache rugosa Cell Culture.

    PubMed

    Park, Woo Tae; Arasu, Mariadhas Valan; Al-Dhabi, Naif Abdullah; Yeo, Sun Kyung; Jeon, Jin; Park, Jong Seok; Lee, Sook Young; Park, Sang Un

    2016-01-01

    The present study aimed to investigate the role of yeast extract and silver nitrate on the enhancement of phenylpropanoid pathway genes and accumulation of rosmarinic acid in Agastache rugosa cell cultures. The treatment of cell cultures with yeast extract (500 mg/L) and silver nitrate (30 mg/L) for varying times enhanced the expression of genes in the phenylpropanoid pathway and the production of rosmarinic acid. The results indicated that the expression of RAS and HPPR was proportional to the amount of yeast extract and silver nitrate. The transcript levels of HPPR under yeast extract treatment were 1.84-, 1.97-, and 2.86-fold higher than the control treatments after 3, 6, and 12 h, respectively, whereas PAL expression under silver nitrate treatment was 52.31-fold higher than in the non-treated controls after 24 h of elicitation. The concentration of rosmarinic acid was directly proportional to the concentration of the applied elicitors. Yeast extract supplementation documented the highest amount of rosmarinic acid at 4.98 mg/g, whereas silver nitrate addition resulted in a comparatively lower amount of rosmarinic acid at 0.65 mg/g. In conclusion, addition of yeast extract to the cell cultures enhanced the accumulation of rosmarinic acid, which was evidenced by the expression levels of the phenylpropanoid biosynthetic pathway genes in A. rugosa. PMID:27043507

  4. Long-Term Fungal Inhibition by Pisum sativum Flour Hydrolysate during Storage of Wheat Flour Bread.

    PubMed

    Rizzello, Carlo Giuseppe; Lavecchia, Anna; Gramaglia, Valerio; Gobbetti, Marco

    2015-06-15

    In order to identify antifungal compounds from natural sources to be used as ingredients in the bakery industry, water/salt-soluble extracts (WSE) from different legume flour hydrolysates obtained by the use of a fungal protease were assayed against Penicillium roqueforti DPPMAF1. The agar diffusion assays allowed the selection of the pea (Pisum sativum) hydrolysate as the most active. As shown by the hyphal radial growth rate, the WSE had inhibitory activity towards several fungi isolated from bakeries. The MIC of the WSE was 9.0 mg/ml. Fungal inhibition was slightly affected by heating and variations in pH. The antifungal activity was attributed to three native proteins (pea defensins 1 and 2 and a nonspecific lipid transfer protein [nsLTP]) and a mixture of peptides released during hydrolysis. The three proteins have been reported previously as components of the defense system of the plant. Five peptides were purified from WSE and were identified as sequences encrypted in leginsulin A, vicilin, provicilin, and the nsLTP. To confirm antifungal activity, the peptides were chemically synthesized and tested. Freeze-dried WSE were used as ingredients in leavened baked goods. In particular, breads made by the addition of 1.6% (wt/wt) of the extract and fermented by baker's yeast or sourdough were characterized for their main chemical, structural, and sensory features, packed in polyethylene bags, stored at room temperature, and compared to controls prepared without pea hydrolysate. Artificially inoculated slices of a bread containing the WSE did not show contamination by fungi until at least 21 days of storage and behaved like the bread prepared with calcium propionate (0.3%, wt/wt). PMID:25862230

  5. Long-Term Fungal Inhibition by Pisum sativum Flour Hydrolysate during Storage of Wheat Flour Bread

    PubMed Central

    Lavecchia, Anna; Gramaglia, Valerio; Gobbetti, Marco

    2015-01-01

    In order to identify antifungal compounds from natural sources to be used as ingredients in the bakery industry, water/salt-soluble extracts (WSE) from different legume flour hydrolysates obtained by the use of a fungal protease were assayed against Penicillium roqueforti DPPMAF1. The agar diffusion assays allowed the selection of the pea (Pisum sativum) hydrolysate as the most active. As shown by the hyphal radial growth rate, the WSE had inhibitory activity towards several fungi isolated from bakeries. The MIC of the WSE was 9.0 mg/ml. Fungal inhibition was slightly affected by heating and variations in pH. The antifungal activity was attributed to three native proteins (pea defensins 1 and 2 and a nonspecific lipid transfer protein [nsLTP]) and a mixture of peptides released during hydrolysis. The three proteins have been reported previously as components of the defense system of the plant. Five peptides were purified from WSE and were identified as sequences encrypted in leginsulin A, vicilin, provicilin, and the nsLTP. To confirm antifungal activity, the peptides were chemically synthesized and tested. Freeze-dried WSE were used as ingredients in leavened baked goods. In particular, breads made by the addition of 1.6% (wt/wt) of the extract and fermented by baker's yeast or sourdough were characterized for their main chemical, structural, and sensory features, packed in polyethylene bags, stored at room temperature, and compared to controls prepared without pea hydrolysate. Artificially inoculated slices of a bread containing the WSE did not show contamination by fungi until at least 21 days of storage and behaved like the bread prepared with calcium propionate (0.3%, wt/wt). PMID:25862230

  6. Improving the robustness of a low-cost insect cell medium for baculovirus biopesticides production, via hydrolysate streamlining using a tube bioreactor-based statistical optimization routine.

    PubMed

    Huynh, Hoai T; Chan, Leslie C L; Tran, Trinh T B; Nielsen, Lars K; Reid, Steven

    2012-01-01

    A critical component of an in vitro production process for baculovirus biopesticides is a growth medium that is efficacious, robust, and inexpensive. An in-house low-cost serum-free medium, VPM3, has been shown to be very promising in supporting Helicoverpa armigera nucleopolyhedrovirus (HaSNPV) production in H. zea insect cell suspension cultures, for use as a biopesticide against the Heliothine pest complex. However, VPM3 is composed of a significant number of undefined components, including five different protein hydrolysates, which introduce a challenging lot-to-lot variability to the production process. In this study, an intensive statistical optimization routine was employed to reduce the number of protein hydrolysates in VPM3 medium. Nearly 300 runs (including replicates) were conducted with great efficiency by using 50 mL TubeSpin® bioreactors to propagate insect cell suspension cultures. Fractional factorial experiments were first used to determine the most important of the five default protein hydrolysates, and to screen for seven potential substitutes for the default meat peptone, Primatone RL. Validation studies informed by the screening tests showed that promising alternative media could be formulated based on just two protein hydrolysates, in particular the YST-AMP (Yeast Extract and Amyl Meat Peptone) and YST-POT (Yeast Extract and Lucratone Potato Peptone) combinations. The YST-AMP (meat-based) and YST-POT (meat-free) variants of VPM3 were optimized using response surface methodology, and were shown to be just as good as the default VPM3 and the commercial Sf-900 II media in supporting baculovirus yields, hence providing a means toward a more reproducible and scalable production process for HaSNPV biopesticides. PMID:22323401

  7. Interactions of grape tannins and wine polyphenols with a yeast protein extract, mannoproteins and β-glucan.

    PubMed

    Mekoue Nguela, J; Poncet-Legrand, C; Sieczkowski, N; Vernhet, A

    2016-11-01

    At present, there is a great interest in enology for yeast derived products to replace aging on lees in winemaking or as an alternative for wine fining. These are yeast protein extracts (YPE), cell walls and mannoproteins. Our aim was to further understand the mechanisms that drive interactions between these components and red wine polyphenols. To this end, interactions between grape skin tannins or wine polyphenols or tannins and a YPE, a mannoprotein fraction and a β-glucan were monitored by binding experiments, ITC and DLS. Depending on the tannin structure, a different affinity between the polyphenols and the YPE was observed, as well as differences in the stability of the aggregates. This was attributed to the mean degree of polymerization of tannins in the polyphenol fractions and to chemical changes that occur during winemaking. Much lower affinities were found between polyphenols and polysaccharides, with different behaviors between mannoproteins and β-glucans. PMID:27211695

  8. [Intensification of extraction by yeast Saccharamyces cerevisiae 1968 of copper ions from a solution in magnetic field].

    PubMed

    Gorobets, S V; Gorobets, O Iu; Goĭko, I Iu; Kasatkina, T P

    2006-01-01

    It was determined whether it is possible to intensify the biosorption of copper ions from a copper sulfate solution with yeast Saccharomyces cerevisiae 1968 by introducing a metal headpiece into the solution and by applying an external magnetic field. The study was carried out in a magnetic field oriented both parallel and perpendicular to the axes of the rods (with parallel and perpendicular geometry of the system) that make up the headpiece. It was shown that the extent of intensification of the extraction of copper ions at different geometries of the system differs insignificantly and that the extraction of copper ions from the solution occurs by biosorption and cementation onto the metal headpiece. PMID:16808351

  9. Malt-yeast extract-sucrose agar, a suitable medium for enumeration and isolation of fungi from silage.

    PubMed Central

    Skaar, I; Stenwig, H

    1996-01-01

    A general medium named malt-yeast extract-sucrose agar (MYSA) containing oxgall was designed. The medium was intended for the enumeration and isolation of molds and yeasts in routine examinations of animal feed stuffs. In this study MYSA was tested as a general medium for mycological examination of silage. The medium was compared with dichloran-rose bengal medium (DRBC) in an examination of more than 500 specimens of big bale grass silage. Selected characteristics of known fungal species commonly isolated from feeds were examined after growth on MYSA and DRBC and on malt extract agar, used as a noninhibitory control medium. MYSA suppressed bacterial growth, without affecting the growth of fungi common in feeds. The fungi growing on MYSA were easily recognized, and the medium seemed to slow radial growth of fungal colonies, which permitted, easy counting. The number of species found was higher on MYSA than on DRBC. When we compared MYSA with DRBC for mycological examination of grass silage samples, MYSA was found to be the medium of choice. PMID:8837416

  10. Effects of algal hydrolysate as reaction medium on enzymatic hydrolysis of lignocelluloses

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Algal biomass has been proposed as a source of lipids and sugars for biofuel productions. However, a substantial portion of potentially valuable algal material remains as a liquid hydrolysate after sugar and lipid extractions. This study examined the effects of an algal hydrolysate on the enzymatic...

  11. Ammonium hydroxide detoxification of spruce acid hydrolysates.

    PubMed

    Alriksson, Björn; Horváth, Ilona Sárvári; Sjöde, Anders; Nilvebrant, Nils-Olof; Jönsson, Leif J

    2005-01-01

    When dilute-acid hydrolysates from spruce are fermented to produce ethanol, detoxification is required to make the hydrolysates fermentable at reasonable rates. Treatment with alkali, usually by overliming, is one of the most efficient approaches. Several nutrients, such as ammonium and phosphate, are added to the hydrolysates prior to fermentation. We investigated the use of NH4OH for simultaneous detoxification and addition of nitrogen source. Treatment with NH4OH compared favorably with Ca(OH)2, Mg(OH)2, Ba(OH)2, and NaOH to improve fermentability using Saccharomyces cerevisiae. Analysis of monosaccharides, furan aldehydes, phenols, and aliphatic acids was performed after the different treatments. The NH4OH treatments, performed at pH 10.0, resulted in a substantial decrease in the concentrations of furfural and hydroxymethylfurfural. Under the conditions studied, NH4OH treatments gave better results than Ca(OH)2 treatments. The addition of an extra nitrogen source in the form of NH4Cl at pH 5.5 did not result in any improvement in fermentability that was comparable to NH4OH treatments at alkaline conditions. The addition of CaCl2 or NH4Cl at pH 5.5 after treatment with NH4OH or Ca(OH)2 resulted in poorer fermentability, and the negative effects were attributed to salt stress. The results strongly suggest that the highly positive effects of NH4OH treatments are owing to chemical conversions rather than stimulation of the yeast cells by ammonium ions during the fermentation. PMID:15930570

  12. Disruption of lipid domain organization in monolayers of complex yeast lipid extracts induced by the lysophosphatidylcholine analogue edelfosine in vivo.

    PubMed

    Mahadeo, Mark; Nathoo, Safia; Ganesan, Suriakarthiga; Driedger, Michael; Zaremberg, Vanina; Prenner, Elmar J

    2015-10-01

    The lysophosphatidylcholine analogue edelfosine is a potent antitumor and antiparasitic drug that targets cell membranes. Previous studies have shown that edelfosine alters membrane domain organization inducing internalization of sterols and endocytosis of plasma membrane transporters. These early events affect signaling pathways that result in cell death. It has been shown that edelfosine preferentially partitions into more rigid lipid domains in mammalian as well as in yeast cells. In this work we aimed at investigating the effect of edelfosine on membrane domain organization using monolayers prepared from whole cell lipid extracts of cells treated with edelfosine compared to control conditions. In Langmuir monolayers we were able to detect important differences to the lipid packing of the membrane monofilm. Domain formation visualized by means of Brewster angle microscopy also showed major morphological changes between edelfosine treated versus control samples. Importantly, edelfosine resistant cells defective in drug uptake did not display the same differences. In addition, co-spread samples of control lipid extracts with edelfosine added post extraction did not fully mimic the results obtained with lipid extracts from treated cells. Altogether these results indicate that edelfosine induces changes in membrane domain organization and that these changes depend on drug uptake. Our work also validates the use of monolayers derived from complex cell lipid extracts combined with Brewster angle microscopy, as a sensitive approach to distinguish between conditions associated with susceptibility or resistance to lysophosphatidylcholine analogues. PMID:26386399

  13. Anti-osteoporosis activity of red yeast rice extract on ovariectomy-induced bone loss in rats.

    PubMed

    Wang, Y F; Liu, W T; Chen, C Y; Ke, H P; Jiang, H L; Chen, X L; Shi, S Y; Wei, W; Zhang, X N

    2015-01-01

    Osteoporosis is the most common bone disease, affecting millions of people worldwide and leading to significant morbidity and high costs. Monacolin K, an extract of red yeast rice (RYR, Hongqu), plays important roles in the management of dyslipidemia, coronary heart disease, and diabetes. Our study aimed to investigate the protective effect of monacolin K on ovariectomy-induced bone loss in rats. Fifty female Sprague-Dawley rats were randomly divided into a sham-operated and five ovariectomized (OVX) groups: OVX with vehicle, OVX with fluvastatin, and OVX with RYR extract of three graded doses. Bone mineral density (BMD), biochemical markers, and cell viability were analyzed by dual energy X-ray absorptiometry, enzyme-linked immunosorbent assay, and 3(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assays. Gene expression was evaluated by real-time polymerase chain reaction amplification and western blot. Our results showed that administration of RYR extract markedly increased the bone mineral density in OVX rats. Moreover, RYR extract decreased the levels of bone turnover markers, including osteocalcin and tartrate resistant acid phosphatase activity. The MMT assay revealed that RYR extract treatment significantly improved the osteoblast viabilities in a dose-dependent manner (P < 0.05). At the molecular level, we further demonstrated that RYR extract enhanced the expression of Bmp2 and Bmp4 both at the mRNA and protein levels. Collectively, these data suggested RYR extract could protect against osteoporosis in ovariectomized rats, most likely through activation of BMP2/4 expression. PMID:26345740

  14. Bio-Based Solvents for Green Extraction of Lipids from Oleaginous Yeast Biomass for Sustainable Aviation Biofuel.

    PubMed

    Breil, Cassandra; Meullemiestre, Alice; Vian, Maryline; Chemat, Farid

    2016-01-01

    Lipid-based oleaginous microorganisms are potential candidates and resources for the sustainable production of biofuels. This study was designed to evaluate the performance of several alternative bio-based solvents for extracting lipids from yeasts. We used experimental design and simulation with Hansen solubility simulations and the conductor-like screening model for realistic solvation (COSMO-RS) to simulate the solubilization of lipids in each of these solvents. Lipid extracts were analyzed by high performance thin-layer chromatography (HPTLC) to obtain the distribution of lipids classes and gas chromatography coupled with a flame ionization detector (GC/FID) to obtain fatty acid profiles. Our aim was to correlate simulation with experimentation for extraction and solvation of lipids with bio-based solvents in order to make a preliminary evaluation for the replacement of hexane to extract lipids from microorganisms. Differences between theory and practice were noted for several solvents, such as CPME, MeTHF and ethyl acetate, which appeared to be good candidates to replace hexane. PMID:26861274

  15. Yeast Infection

    MedlinePlus

    ... a yeast infection and what causes it?  Yeast vaginitis is the second most common vaginal infection after ... risk for yeast Signs and symptoms of yeast vaginitis  Yeast infections may cause no symptoms  Sometimes yeast ...

  16. Selection and use of pectinolytic yeasts for improving clarification and phenolic extraction in winemaking.

    PubMed

    Belda, Ignacio; Conchillo, Lorena B; Ruiz, Javier; Navascués, Eva; Marquina, Domingo; Santos, Antonio

    2016-04-16

    Pectinase enzymes have shown a considerable influence in both, sensitive and technological properties of wines. They can help to improve clarification process, releasing more color and flavor compounds entrapped in grape skin, facilitating the liberation of phenolic compounds. This work aims to find yeasts that, because of their native pectinases, can be applied on combined fermentations with Saccharomyces cerevisiae obtaining significant benefits over single-inoculated traditional fermentations. 462 yeast strains isolated from wineries were identified and tested for several enzymatic activities of recognized interest for enology industry. Considering the 7 identified species, only Aureobasidium pullulans, Metschnikowia pulcherrima and Metschnikowia fructicola showed polygalacturonase activity. Because of its interest in winemaking, due to its reported incidence in wine flavor, the impact of M. pulcherrima as a source of pectinolytic enzymes was analyzed by measuring its influence in filterability, turbidity and the increase on color, anthocyanin and polyphenol content of wines fermented in combination with S. cerevisiae. Among the strains screened, M. pulcherrima NS-EM-34 was selected, due to its polygalacturonase activity, for further characterization in both, laboratory and semi-industrial scale assays. The kinetics concerning several metabolites of enological concern were followed during the entire fermentation process at microvinification scale. Improved results were obtained in the expected parameters when M. pulcherrima NS-EM-34 was used, in comparison to wines fermented with S. cerevisiae alone and combined with other pectinolytic and non-pectinolytic yeasts (A. pullulans and Lachancea thermotolerans, respectively), even working better than commercial enzymes preparations in most parameters. Additionally, M. pulcherrima NS-EM-34 was used at a semi-industrial scale combined with three different S. cerevisiae strains, confirming its potential application for red wine improvement on the mentioned sensorial and technological properties. PMID:26874860

  17. Cellulase Production from Spent Lignocellulose Hydrolysates by Recombinant Aspergillus niger▿

    PubMed Central

    Alriksson, Björn; Rose, Shaunita H.; van Zyl, Willem H.; Sjöde, Anders; Nilvebrant, Nils-Olof; Jönsson, Leif J.

    2009-01-01

    A recombinant Aspergillus niger strain expressing the Hypocrea jecorina endoglucanase Cel7B was grown on spent hydrolysates (stillage) from sugarcane bagasse and spruce wood. The spent hydrolysates served as excellent growth media for the Cel7B-producing strain, A. niger D15[egI], which displayed higher endoglucanase activities in the spent hydrolysates than in standard medium with a comparable monosaccharide content (e.g., 2,100 nkat/ml in spent bagasse hydrolysate compared to 480 nkat/ml in standard glucose-based medium). In addition, A. niger D15[egI] was also able to consume or convert other lignocellulose-derived compounds, such as acetic acid, furan aldehydes, and phenolic compounds, which are recognized as inhibitors of yeast during ethanolic fermentation. The results indicate that enzymes can be produced from the stillage stream as a high-value coproduct in second-generation bioethanol plants in a way that also facilitates recirculation of process water. PMID:19251882

  18. Improvement of Omega-3 Docosahexaenoic Acid Production by Marine Dinoflagellate Crypthecodinium cohnii Using Rapeseed Meal Hydrolysate and Waste Molasses as Feedstock

    PubMed Central

    Gong, Yangmin; Liu, Jiao; Jiang, Mulan; Liang, Zhuo; Jin, Hu; Hu, Xiaojia; Wan, Xia; Hu, Chuanjiong

    2015-01-01

    Rapeseed meal and waste molasses are two important agro-industrial by-products which are produced in large quantities. In this study, solid state fermentation and fungal autolysis were performed to produce rapeseed meal hydrolysate (RMH) using fungal strains of Aspergillus oryzae, Penicillium oxalicum and Neurospora crassa. The hydrolysate was used as fermentation feedstock for heterotrophic growth of microalga Crypthecodinium cohnii that produce docosahexaenoic acid (DHA). The addition of waste molasses as a supplementary carbon source greatly increased the biomass and DHA yield. In the batch fermentations using media composed of diluted RMH (7%) and 1-9% waste molasses, the highest biomass concentration and DHA yield reached 3.43 g/L and 8.72 mg/L, respectively. The algal biomass produced from RMH and molasses medium also had a high percentage of DHA (22-34%) in total fatty acids similar to that of commercial algal biomass. RMH was shown to be rich in nitrogen supply comparable to the commercial nitrogen feedstock like yeast extract. Using RMH as sole nitrogen source, waste molasses excelled other carbon sources and produced the highest concentration of biomass. This study suggests that DHA production of the marine dinoflagellate C. cohnii could be greatly improved by concomitantly using the cheap by-products rapeseed meal hydrolysate and molasses as alternative feedstock. PMID:25942565

  19. Improvement of Omega-3 Docosahexaenoic Acid Production by Marine Dinoflagellate Crypthecodinium cohnii Using Rapeseed Meal Hydrolysate and Waste Molasses as Feedstock.

    PubMed

    Gong, Yangmin; Liu, Jiao; Jiang, Mulan; Liang, Zhuo; Jin, Hu; Hu, Xiaojia; Wan, Xia; Hu, Chuanjiong

    2015-01-01

    Rapeseed meal and waste molasses are two important agro-industrial by-products which are produced in large quantities. In this study, solid state fermentation and fungal autolysis were performed to produce rapeseed meal hydrolysate (RMH) using fungal strains of Aspergillus oryzae, Penicillium oxalicum and Neurospora crassa. The hydrolysate was used as fermentation feedstock for heterotrophic growth of microalga Crypthecodinium cohnii that produce docosahexaenoic acid (DHA). The addition of waste molasses as a supplementary carbon source greatly increased the biomass and DHA yield. In the batch fermentations using media composed of diluted RMH (7%) and 1-9% waste molasses, the highest biomass concentration and DHA yield reached 3.43 g/L and 8.72 mg/L, respectively. The algal biomass produced from RMH and molasses medium also had a high percentage of DHA (22-34%) in total fatty acids similar to that of commercial algal biomass. RMH was shown to be rich in nitrogen supply comparable to the commercial nitrogen feedstock like yeast extract. Using RMH as sole nitrogen source, waste molasses excelled other carbon sources and produced the highest concentration of biomass. This study suggests that DHA production of the marine dinoflagellate C. cohnii could be greatly improved by concomitantly using the cheap by-products rapeseed meal hydrolysate and molasses as alternative feedstock. PMID:25942565

  20. Effects of a dietary yeast extract on hematological parameters, heterophil function, and bacterial clearance in turkey poults challenged with Escherichia coli and subjected to transport stress

    Technology Transfer Automated Retrieval System (TEKTRAN)

    There is a need to develop nutritional methods for controlling pathogens in poultry production. A standardized yeast extract supplement, Alphamune™ (YE), was added to turkey poult diets. Male poults were challenged by air sac injection with 60 cfu of E. coli at 1 week of age. At 3 weeks of age chal...

  1. Effects of a dietary yeast extract on hematological parameters, heterophil function, and bacterial clearance in turkey poults challenged with Escherichia coli and subjected to transport stress

    Technology Transfer Automated Retrieval System (TEKTRAN)

    There is a need to develop nutritional methods for controlling pathogens in poultry production. A standardized yeast extract supplement, Alphamune (YE), was added to turkey poult diets. Male poults were challenged by air sac injection with 60 cfu of E. coli at 1 week of age. At 3 weeks of age chal...

  2. INFLUENCE OF HEN AGE ON THE RESPONSE OF TURKEY POULTS TO COLD STRESS, ESCHERICHIA COLI CHALLENGE, AND TREATMENT WITH A YEAST EXTRACT ANTIBIOTIC ALTERNATIVE

    Technology Transfer Automated Retrieval System (TEKTRAN)

    1. Two duplicated battery trials were conducted to evaluate a standardized Yeast Extract feed supplement, (Alphamune) in a cold stress-Escherichia coli challenge of one-week-old turkeys. Trial 1 used day-old male Hybrid Converter poults from 33-week-old hens in their 2nd week of lay. Trial 2 used ...

  3. The effect of a yeast extract feed additive on turkeys challenged with Escherichia coli and Listeria monocytogenes and subjected to transport stress

    Technology Transfer Automated Retrieval System (TEKTRAN)

    There is a need to develop nutritional methods for controlling pathogens in poultry production. A yeast extract supplement, Alphamune™ (YE) was added to the diet of turkeys which were exposed to E. coli and L. monocytogenes Scott A at 16 wks of age using coarse spray and feed inclusion. Positive c...

  4. Nucleotide-excision repair of DNA in cell-free extracts of the yeast Saccharomyces cerevisiae.

    PubMed Central

    Wang, Z; Wu, X; Friedberg, E C

    1993-01-01

    A wide spectrum of DNA lesions are repaired by the nucleotide-excision repair (NER) pathway in both eukaryotic and prokaryotic cells. We have developed a cell-free system in Saccharomyces cerevisiae that supports NER. NER was monitored by measuring repair synthesis in DNA treated with cisplatin or with UV radiation. Repair synthesis in vitro was defective in extracts of rad1, rad2, and rad10 mutant cells, all of which have mutations in genes whose products are known to be required for NER in vivo. Additionally, repair synthesis was complemented by mixing different mutant extracts, or by adding purified Rad1 or Rad10 protein to rad1 or rad10 mutant extracts, respectively. The latter observation demonstrates that the Rad1 and Rad10 proteins directly participate in the biochemical pathway of NER. NER supported by nuclear extracts requires ATP and Mg2+ and is stimulated by polyethylene glycol and by small amounts of whole cell extract containing overexpressed Rad2 protein. The nuclear extracts also contain base-excision repair activity that is present at wild-type levels in rad mutant extracts. This cell-free system is expected to facilitate studies on the biochemical pathway of NER in S. cerevisiae. Images Fig. 1 Fig. 2 Fig. 3 Fig. 5 PMID:8506335

  5. Photodynamic inactivation of yeast and bacteria by extracts of Alternanthera brasiliana.

    PubMed

    Andreazza, Nathalia L; de Lourenco, Caroline C; Siqueira, Carlos A T; Sawaya, Alexandra C H F; Lapinski, Tadia F; Gasparetto, Adriana; Khouri, Sonia; Zamuner, Stella R; Munin, Egberto; Salvador, Marcos Jose

    2013-08-01

    This study was undertaken to evaluate the effect of Alternathera brasiliana (Amaranthaceae) extracts as photosensitizing agents in photodynamic antimicrobial therapies (PACT) against Staphylococcus aureus, Staphylococcus epidermidis and Candida dubliniensis. The crude hexane and ethanol extracts were obtained from A. brasiliana whole plant and showed absortion from 650 to 700 nm. Also, singlet molecular oxygen (1O2) production (type II photosensitization reaction) was examined, and the results show that 1,3-diphenylisobenzofuran photodegradation was greatly enhanced in the presence of the A. brasiliana extracts. One plate in each assay was irradiated while the other was not irradiated, the number of colony-forming units per milliliter (CFU/mL) was obtained, and data analyzed by the Tukey test. The chemical composition of the extracts was determined by chromatographic and spectrometric techniques; steroids, triterpenes, and flavonoids were identified. Laser irradiation alone at 685 nm using diode laser, output power of 35 mW, and energy of 28 J/cm2, or non-irradiated crude extracts in sub-inhibitory concentration did not reduce the number of CFU/mL significantly, whereas irradiated hexane and ethanol extracts, in sub-inhibitory concentrations, inhibited the growth of these microorganisms. The photoactivation of hexane and ethanol extracts of A. brasiliana, in sub-inhibitory concentrations, using red laser radiation at 685 nm had an antimicrobial effect. PMID:23547779

  6. Kinetic considerations about the study of alcoholic fermentations in starch hydrolysate

    SciTech Connect

    Converti, A.; Perego, P.; Del Borghi, M.; Parisi, F.; Ferraiolo, G.

    1986-05-01

    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.

  7. Effects of bentonite and yeast extract as nutrient on decrease in hydraulic conductivity of porous media due to CaCO3 precipitation induced by Sporosarcina pasteurii.

    PubMed

    Eryrk, Ka?an; Yang, Suyin; Suzuki, Daisuke; Sakaguchi, Iwao; Katayama, Arata

    2015-10-01

    The reduction mechanism of hydraulic conductivity was investigated in porous media treated with bentonite and CaCO3 precipitates induced by growing cells of Sporosarcina pasteurii (ATCC 11859). Bentonite, the bacterial cells, and a precipitation solution, composing of 0.5M CaCl2 and 0.5M urea with or without 2% weight/volume yeast extract allowing the bacterial growth were sequentially introduced into the continuous-flow columns containing glass beads between 0.05 and 3mm in diameter. The treatments reduced the hydraulic conductivity of the columns from between 8.4נ10(-1) and 4.1נ10(-3)cm/s to between 9.9נ10(-4) and 2.1נ10(-6)cm/s as the lowest. With yeast extract, the conductivity continuously decreased during four days of the experiment, while became stable after two days without yeast extract. Introduction of the bacterial cells did not decrease the conductivity. The reduction in hydraulic conductivity was inversely correlated with the volume occupied by the depositions of bentonite and CaCO3 precipitates in column, showing the same efficiency but a larger effect of the CaCO3 precipitates with increasing volume by bacterial growth. The smaller glass beads resulted in larger volume of the depositions. Bentonite increased the deposition of CaCO3 precipitates. Analysis using the Kozeny-Carman equation suggested that without yeast extract, bentonite and the CaCO3 precipitates formed aggregates with glass beads, thus increasing their diameter and consequently decreasing the pore size in the column. With yeast extract, in addition to the aggregates, the individual CaCO3 precipitates formed separately from the aggregates reduced the hydraulic conductivity. PMID:25736267

  8. Detoxification of rice straw and olive tree pruning hemicellulosic hydrolysates employing Saccharomyces cerevisiae and its effect on the ethanol production by Pichia stipitis.

    PubMed

    Fonseca, Bruno Guedes; Puentes, Juan Gabriel; Mateo, Soledad; Sánchez, Sebastian; Moya, Alberto J; Roberto, Inês Conceição

    2013-10-01

    The aim of this work was to study the ability of Saccharomyces cerevisiae (baker's yeast) to metabolize a variety of aromatic compounds found in rice straw (RSHH) and olive tree pruning (OTHH) hemicellulosic hydrolysates, obtained by acid hydrolysis at different sugar and toxic compound concentrations. Initially, the hydrolysates were inoculated with S. cerevisiae (10 g L(-1)) and incubated at 30 °C under agitation at 200 rpm for 6 h. The results showed that this yeast was able to utilize phenolic and furan compounds in both hemicellulose hydrolysates. Next, the treated hydrolysates were inoculated with Pichia stipitis NRRL Y-7124 to evaluate the effect of biotransformation of aromatic compounds on ethanol production, and better fermentation results were obtained in this case compared to untreated ones. The untreated hemicellulose hydrolysates were not able to be fermented when they were incubated with Pichia stipitis. However, in RSHH treated hydrolysates, ethanol (Y(P/S)) and biomass (Y(X/S)) yields and volumetric ethanol productivity (Q(P)) were 0.17 g g(-1), 0.15 g g(-1) and 0.09 g L(-1) h(-1), respectively. The OTHH-treated hydrolysates showed less favorable results compared to RSHH, but the fermentation process was favored with regard to untreated hydrolysate. These results showed that the fermentation by P. stipitis in untreated hydrolysates was strongly inhibited by toxic compounds present in the media and that treatment with S. cerevisiae promoted a significant reduction in their toxicities. PMID:23992561

  9. Improvement of grape and wine phenolic content by foliar application to grapevine of three different elicitors: Methyl jasmonate, chitosan, and yeast extract.

    PubMed

    Portu, Javier; López, Rosa; Baroja, Elisa; Santamaría, Pilar; Garde-Cerdán, Teresa

    2016-06-15

    Phenolic compounds play a key role in grape and wine organoleptic properties, being therefore a key parameter in wine quality. Elicitor application constitutes an interesting field of research since it is indirectly involved in the accumulation of phenolic compounds. The aim of this study was to compare the effect of the application of three different elicitors on both grape and wine phenolic content. Methyl jasmonate, chitosan, and a commercial yeast extract were applied to the canopy at veraison and one week later. Results showed that foliar treatments carried out with methyl jasmonate and yeast extract achieved the best results, increasing grape and wine anthocyanin content when compared to the control. Moreover, the application of the yeast elicitor also enhanced grape stilbene content. In contrast, the chitosan treatment did not have a substantial impact on the phenolic compounds. The results of this study indicate that methyl jasmonate and yeast extract applications could be a simple practice to increase grape and wine phenolic content. PMID:26868568

  10. Application of supercritical CO(2) extraction for the elimination of odorant volatile compounds from winemaking inactive dry yeast preparation.

    PubMed

    Pozo-Bayn, Mara Angeles; Andjar-Ortiz, Inmaculada; Mendiola, Jose A; Ibez, Elena; Moreno-Arribas, M Victoria

    2010-03-24

    A procedure based on the application of supercritical CO(2) extraction to reduce and/or to remove odorant volatile compounds from a winemaking inactive dry yeast (IDY) preparation has been set up. By applying a factorial design, a screening of different temperatures and pressure conditions was assayed in order to determine the optimal deodorization conditions, and afterward the effect of several sample pretreatments was investigated. The best extraction conditions were achieved at 200 atm and 60 degrees C, applying the cryogenic grinding of the sample and using 40% (w/w) ethanol as cosolvent. By using these conditions, it was possible to reduce to approximately 70% of the volatile compounds present in the samples that may be released into the wines and therefore affecting their sensory characteristics. Odorant volatile compounds such as 2-methylhydroxypyrrole, 2-ethyl-6-methylpyrazine, and 2,3,5-trimethylpyrazine completely disappeared from the deodorized sample as verified by GC-O analysis. Additional experiments in model wines confirmed the low release of volatile compounds from the deodorized samples, without provoking any change to their nonvolatile composition (nitrogen compounds and neutral polysaccharides) that is related to the technological properties of these preparations. PMID:20170168

  11. Extraction of yeast mitochondrial membrane proteins by solubilization and detergent/polymer aqueous two-phase partitioning.

    PubMed

    Everberg, Henrik; Gustavsson, Niklas; Tjerneld, Folke

    2009-01-01

    Identification and characterization of membrane proteins is of increasing importance in modern proteomic studies. It is of central interest to have access to methods that combine efficient solubilization with enrichment of proteins and intact protein complexes. Separation methods have been developed based on nondenaturing detergent extraction of yeast mitochondrial membrane proteins followed by enrichment of hydrophobic proteins in aqueous two-phase system. Combining the zwitterionic detergent Zwittergent 3-10 and the nonionic detergent Triton X-114 results in a complementary solubilization of proteins, which is similar to that of the anionic detergent sodium dodecyl sulfate (SDS) but with the important advantage of being nondenaturing. Detergent/polymer two-phase system partitioning offers removal of soluble proteins, which can be further improved by manipulation of the driving forces governing protein distribution between the phases. Integral and peripheral membrane protein subunits from intact membrane protein complexes partition to the detergent phase while soluble proteins are found in the polymer phase. A protocol is presented which combines nondenaturing solubilization of membrane proteins with extraction in detergent/polymer two-phase system for application in proteomic studies as a mild and efficient method for enrichment of membrane proteins and membrane protein complexes. PMID:19153685

  12. Purification of xylose in simulated hemicellulosic hydrolysates using a two-step emulsion liquid membrane process.

    PubMed

    Lee, Sang Cheol

    2014-10-01

    Purification of xylose in simulated hemicellulosic hydrolysates was attempted using a two-step emulsion liquid membrane (ELM) process. The effects of various experimental variables on extraction of each component in the hydrolysates were investigated in the ELM steps. In the first ELM step, acetic acid could be selectively removed from the hydrolysates and highly enriched in the stripping phase, and loss of xylose was insignificant. In the second ELM step, sulfuric acid could be selectively removed from simulated acetic acid-free hemicellulosic hydrolysates and somewhat enriched in the stripping phase. There was just small loss of xylose, and the final pH of the feed phase approached a pH level suitable for ethanol fermentation. Also, concentration of xylose in the feed phase was attained as an incidental outcome during each ELM run. Conclusively, the two-step ELM process was found to be a promising futuristic technology for purification of sugars in real hemicellulosic hydrolysates. PMID:25108268

  13. Extraction of ethanol with higher carboxylic acid solvents and their toxicity to yeast

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In a screening exercise for ethanol-selective extraction solvents, partitioning of ethanol and water from a 5 wt% aqueous solution into several C8 – C18 carboxylic acids was studied. Results for the acids are compared with those from alcohols of similar structure. In all cases studied, the acids exh...

  14. A new β-glucosidase producing yeast for lower-cost cellulosic ethanol production from xylose-extracted corncob residues by simultaneous saccharification and fermentation.

    PubMed

    Liu, Z Lewis; Weber, Scott A; Cotta, Michael A; Li, Shi-Zhong

    2012-01-01

    This study reports a new yeast strain of Clavispora NRRL Y-50464 that is able to utilize cellobiose as sole source of carbon and produce sufficient native β-glucosidase enzyme activity for cellulosic ethanol production using SSF. In addition, this yeast is tolerant to the major inhibitors derived from lignocellulosic biomass pre-treatment such as 2-furaldehyde (furfural) and 5-(hydroxymethyl)-2-furaldehyde (HMF), and converted furfural into furan methanol in less than 12h and HMF into furan-2,5-dimethanol within 24h in the presence of 15 mM each of furfural and HMF. Using xylose-extracted corncob residue as cellulosic feedstock, an ethanol production of 23 g/l was obtained using 25% solids loading at 37 °C by SSF without addition of exogenous β-glucosidase. Development of this yeast aids renewable biofuels development efforts for economic consolidated SSF bio-processing. PMID:22133603

  15. Effect of different hydrolysates of whey protein on hepatic glutathione content in mice.

    PubMed

    Pacheco, Maria Teresa Bertoldo; Sgarbieri, Valdemiro Carlos

    2005-01-01

    This study was designed to compare the effects of diets prepared with enzymatic hydrolysate of a whey protein concentrate (WPC) by pancreatin, protamex (Novo Nordisk, Bagsvaerd, Denmark), and alcalase proteases on the hepatic glutathione content in mice. The undenatured WPC was produced in a pilot plant by membrane technology (microfiltration/diafiltration) after separation of the casein clot through a conventional process. All three hydrolysates with 20% degree of hydrolysis showed an amino acid profile similar to WPC. Male A/J mice were fed on diets containing 20% WPC or hydrolysates. Commercial casein was used as a reference protein in the biological assays. The glutathione content was determined after liver extraction through high-performance capillary electrophoresis. WPC and its pancreatin and protamex hydrolysates showed higher ability to stimulate liver glutathione synthesis than alcalase hydrolysate. This difference was probably related to an amino acid sequence in the peptides that were formed during hydrolysis of whey proteins. Commercial casein and WPC alcalase hydrolysate produced lower stimulation of liver glutathione synthesis (7.09 and 5.66 micromol/g of wet weight) compared with WPC and pancreatin and protamex hydrolysates (8.72, 8.71, and 8.45 micromol/g of wet weight, respectively). These results indicate that the hydrolysates obtained by treatment with pancreatin and protamex are good sources of peptides with activity to stimulate glutathione synthesis. PMID:16176144

  16. Production of defatted palm kernel cake protein hydrolysate as a valuable source of natural antioxidants.

    PubMed

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

    2012-01-01

    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

  17. Protein Hydrolysates/Peptides in Animal Nutrition

    NASA Astrophysics Data System (ADS)

    McCalla, Jeff; Waugh, Terry; Lohry, Eric

    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.

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

    PubMed Central

    2014-01-01

    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

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

    PubMed

    Szymanski, Eva Paige; Kerscher, Oliver

    2013-01-01

    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

  20. Valorisation of side streams from wheat milling and confectionery industries for consolidated production and extraction of microbial lipids.

    PubMed

    Tsakona, Sofia; Skiadaresis, Argyrios G; Kopsahelis, Nikolaos; Chatzifragkou, Afroditi; Papanikolaou, Seraphim; Kookos, Ioannis K; Koutinas, Apostolis A

    2016-05-01

    Crude enzymes produced via solid state fermentation (SSF) using wheat milling by-products have been employed for both fermentation media production using flour-rich waste (FRW) streams and lysis of Rhodosporidium toruloides yeast cells. Filter sterilization of crude hydrolysates was more beneficial than heat sterilization regarding yeast growth and microbial oil production. The initial carbon to free amino nitrogen ratio of crude hydrolysates was optimised (80.2g/g) in fed-batch cultures of R. toruloides leading to a total dry weight of 61.2g/L with microbial oil content of 61.8% (w/w). Employing a feeding strategy where the glucose concentration was maintained in the range of 12.2-17.6g/L led to the highest productivity (0.32 g/L·h). The crude enzymes produced by SSF were utilised for yeast cell treatment leading to simultaneous release of around 80% of total lipids in the broth and production of a hydrolysate suitable as yeast extract replacement. PMID:26769508

  1. Influence of agronomic factors and extraction rate on the acrylamide contents in yeast-leavened breads.

    PubMed

    Claus, Achim; Schreiter, Pat; Weber, Albrecht; Graeff, Simone; Herrmann, Wilfried; Claupein, Wilhelm; Schieber, Andreas; Carle, Reinhold

    2006-11-15

    Because the impact of agronomical factors on bakery products quality is still an insufficiently studied field, acrylamide contents of breads produced from flours of nine wheat, two rye, and two spelt varieties harvested in 2003 and 2004 were investigated. It could be demonstrated that acrylamide content in bread strongly depends on the cultivar, with extremes differing by a factor of 5.4 due to marked differences in free asparagine and crude protein contents. Nitrogen fertilization also resulted in elevated amino acid and protein contents, thus increasing acrylamide levels from 10.6 to 55.6 mug/kg. Independent of fertilization, harvest year turned out to be another factor influencing acrylamide formation. Breads produced from 2003 flours showed significantly higher acrylamide contents than those of 2004, which was ascribed to favorable light and temperature conditions during the cultivation period, thus enhancing amino acid and protein contents. Sprouting of the grain also resulted in significantly higher acrylamide levels, which was attributed to elevated enzyme activities and the formation of precursors from protein and starch. Furthermore, bakery products made from flours with higher extraction rates were shown to contain higher acrylamide levels resulting from extracted free asparagine and protein from the aleuron layers of the cereal grain. PMID:17090149

  2. Yeast extract promotes decolorization of azo dyes by stimulating azoreductase activity in Shewanella sp. strain IFN4.

    PubMed

    Imran, Muhammad; Arshad, Muhammad; Negm, Fayek; Khalid, Azeem; Shaharoona, Baby; Hussain, Sabir; Mahmood Nadeem, Sajid; Crowley, David E

    2016-02-01

    Biological treatment of azo dyes commonly requires a combined anaerobic-aerobic process in which initial decolorization is achieved by reductive cleavage of azo bonds on the parent molecule. The present study was conducted to examine the relative importance of co-substrates for driving reductive decolorization of azo dyes by Shewanella sp. strain IFN4 using whole cells and enzyme assays. Results showed that the dye decolorization by strain IFN4 was faster in medium containing 1gL(-1) yeast extract (YE) as compared to nine other co-substrates. Moreover, only YE stimulated azoreductase activity (increased from 1.32 to 4.19U/mg protein). Increasing the level of YE up to 8gL(-)(1) resulted into 81% decolorization of the dye in 1h along with an increase in azoreductase activity up to 6.16U/mg protein. Among the components of YE, only riboflavin stimulated the decolorization process as well as enzyme activity. Moreover, strain IFN4 demonstrated flavin reductase activity, and a significant correlation (r(2)=0.98) between flavin reduction and dye reduction by this strain emphasized the involvement of flavin compounds in the decolorization process. The results of this study show that YE serves both as a source of reducing equivalents and an electron shuttle for catalyzing dye reduction. PMID:26454074

  3. Synthesis of yeast extract-stabilized Cu nanoclusters for sensitive fluorescent detection of sulfide ions in water.

    PubMed

    Jin, Lihua; Zhang, Zaihua; Tang, Anwen; Li, Cong; Shen, Yehua

    2016-05-15

    In this work, we have presented a novel strategy to utilize as-synthesized yeast extract-stabilized Cu nanoclusters (Cu NCs) for sensitive and selective detection of S(2-). The fluorescence intensity of Cu NCs was enhanced significantly in the presence of both Na2S2O8 and S(2-). By virtue of this specific response, a Cu NC-based fluorescent turn-on sensor was developed, which allows the detection of S(2-) in the range of 0.02-0.8μM with a detection limit of 10nM. The enhancing mechanism was also discussed based on fluorescence decay, transmission electron microscopy (TEM) and dynamic light scattering (DLS) studies, indicating that S(2-) enhanced the Cu NCs emission mainly through sulfide-induced aggregation of Cu NCs. Furthermore, we demonstrated the usability of the present approach for the detection of S(2-) in water samples, which illustrates its great potential for the environmental monitoring and water quality inspection fields. PMID:26703988

  4. Influence of the propagation strategy for obtaining robust Saccharomyces cerevisiae cells that efficiently co-ferment xylose and glucose in lignocellulosic hydrolysates.

    PubMed

    Tomás-Pejó, Elia; Olsson, Lisbeth

    2015-11-01

    Development of xylose-fermenting yeast strains that are tolerant to the inhibitors present in lignocellulosic hydrolysates is crucial to achieve efficient bioethanol production processes. In this study, the importance of the propagation strategy for obtaining robust cells was studied. Addition of hydrolysate during propagation of the cells adapted them to the inhibitors, resulting in more tolerant cells with shorter lag phases and higher specific growth rates in minimal medium containing acetic acid and vanillin than unadapted cells. Addition of hydrolysate during propagation also resulted in cells with better fermentation capabilities. Cells propagated without hydrolysate were unable to consume xylose in wheat straw hydrolysate fermentations, whereas 40.3% and 97.7% of the xylose was consumed when 12% and 23% (v/v) hydrolysate, respectively, was added during propagation. Quantitative polymerase chain reaction revealed changes in gene expression, depending on the concentration of hydrolysate added during propagation. This study highlights the importance of using an appropriate propagation strategy for the optimum performance of yeast in fermentation of lignocellulosic hydrolysates. PMID:25989314

  5. Influence of the propagation strategy for obtaining robust Saccharomyces cerevisiae cells that efficiently co-ferment xylose and glucose in lignocellulosic hydrolysates

    PubMed Central

    Tomás-Pejó, Elia; Olsson, Lisbeth

    2015-01-01

    Development of xylose-fermenting yeast strains that are tolerant to the inhibitors present in lignocellulosic hydrolysates is crucial to achieve efficient bioethanol production processes. In this study, the importance of the propagation strategy for obtaining robust cells was studied. Addition of hydrolysate during propagation of the cells adapted them to the inhibitors, resulting in more tolerant cells with shorter lag phases and higher specific growth rates in minimal medium containing acetic acid and vanillin than unadapted cells. Addition of hydrolysate during propagation also resulted in cells with better fermentation capabilities. Cells propagated without hydrolysate were unable to consume xylose in wheat straw hydrolysate fermentations, whereas 40.3% and 97.7% of the xylose was consumed when 12% and 23% (v/v) hydrolysate, respectively, was added during propagation. Quantitative polymerase chain reaction revealed changes in gene expression, depending on the concentration of hydrolysate added during propagation. This study highlights the importance of using an appropriate propagation strategy for the optimum performance of yeast in fermentation of lignocellulosic hydrolysates. PMID:25989314

  6. Biotechnological strategies to overcome inhibitors in lignocellulose hydrolysates for ethanol production: review.

    PubMed

    Parawira, W; Tekere, M

    2011-03-01

    One of the major challenges faced in commercial production of lignocellulosic bioethanol is the inhibitory compounds generated during the thermo-chemical pre-treatment step of biomass. These inhibitory compounds are toxic to fermenting micro-organisms. The ethanol yield and productivity obtained during fermentation of lignocellulosic hydrolysates is decreased due to the presence of inhibiting compounds, such as weak acids, furans and phenolic compounds formed or released during thermo-chemical pre-treatment step such as acid and steam explosion. This review describes the application and/or effect of biological detoxification (removal of inhibitors before fermentation) or use of bioreduction capability of fermenting yeasts on the fermentability of the hydrolysates. Inhibition of yeast fermentation by the inhibitor compounds in the lignocellulosic hydrolysates can be reduced by treatment with enzymes such as the lignolytic enzymes, for example, laccase and micro-organisms such as Trichoderma reesei, Coniochaeta ligniaria NRRL30616, Trametes versicolor, Pseudomonas putida Fu1, Candida guilliermondii, and Ureibacillus thermosphaericus. Microbial and enzymatic detoxifications of lignocellulosic hydrolysate are mild and more specific in their action. The efficiency of enzymatic process is quite comparable to other physical and chemical methods. Adaptation of the fermentation yeasts to the lignocellulosic hydrolysate prior to fermentation is suggested as an alternative approach to detoxification. Increases in fermentation rate and ethanol yield by adapted micro-organisms to acid pre-treated lignocellulosic hydrolysates have been reported in some studies. Another approach to alleviate the inhibition problem is to use genetic engineering to introduce increased tolerance by Saccharomyces cerevisiae, for example, by overexpressing genes encoding enzymes for resistance against specific inhibitors and altering co-factor balance. Cloning of the laccase gene followed by heterologous expression in yeasts was shown to provide higher enzyme yields and permit production of laccases with desired properties for detoxification of lignocellulose hydrolysates. A combination of more inhibitor-tolerant yeast strains with efficient feed strategies such as fed-batch will likely improve lignocellulose-to-ethanol process robustness. PMID:20513164

  7. System and method for conditioning a hardwood pulp liquid hydrolysate

    DOEpatents

    Waite, Darrell M; Arnold, Richard; St. Pierre, James; Pendse, Hemant P; Ceckler, William H

    2013-12-17

    A system and method for hardwood pulp liquid hydrolysate conditioning includes a first evaporator receives a hardwood mix extract and outputting a quantity of vapor and extract. A hydrolysis unit receives the extract, hyrolyzes and outputs to a lignin separation device, which separates and recovers a quantity of lignin. A neutralization device receives extract from the lignin separation device and a neutralizing agent, producing a mixture of solid precipitate and a fifth extract. The solid precipitate is removed from the fifth extract. A second evaporator removes a quantity of acid from the fifth extract in a vapor form. This vapor may be recycled to improve total acid recovery or discarded. A desalination device receives the diluted extract, separates out some of the acid and salt and outputs a desalinated solution.

  8. System and method for conditioning a hardwood pulp liquid hydrolysate

    SciTech Connect

    Waite, Darrell; Arnold, Richard; St. Pierre, James; Pendse, Hemant P.; Ceckler, William H.

    2015-06-30

    A system and method for hardwood pulp liquid hydrolysate conditioning includes a first evaporator receives a hardwood mix extract and outputting a quantity of vapor and extract. A hydrolysis unit receives the extract, hydrolyzes and outputs to a lignin separation device, which separates and recovers a quantity of lignin. A neutralization device receives extract from the lignin separation device and a neutralizing agent, producing a mixture of solid precipitate and a fifth extract. The solid precipitate is removed from the fifth extract. A second evaporator removes a quantity of acid from the fifth extract in a vapor form. This vapor may be recycled to improve total acid recovery or discarded. A desalination device receives the diluted extract, separates out some of the acid and salt and outputs a desalinated solution.

  9. Microwave, ultrasound, thermal treatments, and bead milling as intensification techniques for extraction of lipids from oleaginous Yarrowia lipolytica yeast for a biojetfuel application.

    PubMed

    Meullemiestre, Alice; Breil, Cassandra; Abert-Vian, Maryline; Chemat, Farid

    2016-07-01

    In the present work, two different ways of lipids extraction from Yarrowia lipolytica yeast were investigated in order to maximize the extraction yield. Firstly, various modern techniques of extraction including ultrasound, microwave, and bead milling were tested to intensify the efficiency of lipid recovery. Secondly, several pretreatments such as freezing/defrosting, cold drying, bead milling, and microwave prior two washing of mixture solvent of chloroform:methanol (1:2, v/v) were study to evaluate the impact on lipid recovery. All these treatments were compared to conventional maceration, in terms of lipids extraction yield and lipid composition analysis. The main result of this study is the large difference of lipid recovery among treatments and the alteration of lipids profile after microwave and ultrasound techniques. PMID:27017129

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

    DOEpatents

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

    1992-01-01

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

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

    SciTech Connect

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

    1991-01-16

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

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

    DOEpatents

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

    1992-03-31

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

  13. Combined extractives of red yeast rice, bitter gourd, chlorella, soy protein, and licorice improve total cholesterol, low-density lipoprotein cholesterol, and triglyceride in subjects with metabolic syndrome.

    PubMed

    Lee, I-Te; Lee, Wen-Jane; Tsai, Ching-Min; Su, Ih-Jen; Yen, Hsien-Tung; Sheu, Wayne H-H

    2012-02-01

    In this study, we aimed to examine the effects of a plant-extractive compound on lipid profiles in subjects with metabolic syndrome. We hypothesized that extractives from red yeast rice, bitter gourd, chlorella, soy protein, and licorice have synergistic benefits on cholesterol and metabolic syndrome. In this double-blinded study, adult subjects with metabolic syndrome were randomized to receive a plant-extractive compound or a placebo treatment for 12 weeks. Both total cholesterol (5.4 ± 0.8 to 4.4 ± 0.6 mmol/L, P < .001) and low-density lipoprotein cholesterol (3.4 ± 0.7 to 2.7 ± 0.5 mmol/L, P < .001) were significantly reduced after treatment with the plant extractives, and the magnitudes of reduction were significantly greater than in the placebo group (-1.0 ± 0.6 vs 0.0 ± 0.6mmol/L, P < .001; -0.7 ± 0.6 vs 0.0 ± 0.6 mmol/L, P < .001). The reduction in the fasting triglycerides level was significantly greater in the plant-extractive group than in the placebo group (-0.5 ± 0.8 vs -0.2 ± 1.0 mmol/L, P = .039). There was also a significantly greater reduction in the proportion of subjects with hypertensive criteria in the plant-extractive group than in the placebo group (P = .040). In conclusion, the plant extractives from red yeast rice, bitter gourd, chlorella, soy protein, and licorice were effective in reducing total and low-density lipoprotein cholesterol. The plant extractives also showed potential for reducing triglyceride and normalizing blood pressure. PMID:22348456

  14. Effects of Ca(OH)(2) treatments ("overliming") on the composition and toxicity of bagasse hemicellulose hydrolysates.

    PubMed

    Martinez, A; Rodriguez, M E; York, S W; Preston, J F; Ingram, L O

    2000-09-01

    Hemicellulose syrups from dilute sulfuric acid hydrolysates of hemicellulose contain inhibitors that prevent efficient fermentation by yeast or bacteria. It is well known that the toxicity of these hydrolysate syrups can be ameliorated by optimized "overliming" with Ca(OH)(2). We have investigated the optimization of overliming treatments for sugar cane bagasse hydrolysates (primarily pentose sugars) using recombinant Escherichia coli LY01 as the biocatalyst. A comparison of composition before and after optimal overliming revealed a substantial reduction in furfural, hydroxymethylfurfural, and three unidentified high-performance liquid chromatography (HPLC) peaks. Organic acids (acetic, formic, levulinic) were not affected. Similar changes have been reported after overliming of spruce hemicellulose hydrolysates (Larsson et al., 1999). Our studies further demonstrated that the extent of furan reduction correlated with increasing fermentability. However, furan reduction was not the sole cause for reduced toxicity. After optimal overliming, bagasse hydrolysate was rapidly and efficiently fermented (>90% yield) by LY01. During these studies, titration, and conductivity were found to be in excellent agreement as methods to estimate sulfuric acid content. Titration was also found to provide an estimate of total organic acids in hydrolysate, which agreed well with the sum of acetic, levulinic, and formic acids obtained by HPLC. Titration of acids, measurement of pH before and after treatment, and furan analyses are proposed as relatively simple methods to monitor the reproducibility of hydrolysate preparations and the effectiveness of overliming treatments. PMID:10898862

  15. Carbon source utilization and inhibitor tolerance of 45 oleaginous yeast species

    PubMed Central

    Sitepu, Irnayuli; Selby, Tylan; Lin, Ting; Zhu, Shirley; Boundy-Mills, Kyria

    2014-01-01

    Conversion of lignocellulosic hydrolysates to lipids using oleaginous (high lipid) yeasts requires alignment of the hydrolysate composition with the characteristics of the yeast strain, including ability to utilize certain nutrients, ability to grow independently of costly nutrients such as vitamins, and ability to tolerate inhibitors. Some combination of these characteristics may be present in wild strains. In this study, 48 oleaginous yeast strains belonging to 45 species were tested for ability to utilize carbon sources associated with lignocellulosic hydrolysates, tolerate inhibitors, and grow in medium without supplemented vitamins. Some well-studied oleaginous yeast species, as well as some that have not been frequently utilized in research or industrial production, emerged as promising candidates for industrial use due to ability to utilize many carbon sources, including Cryptococcus aureus, Cryptococcus laurentii, Hanaella aff. zeae, Tremella encephala, and Trichosporon coremiiforme. Other species excelled in inhibitor tolerance, including Candida aff. tropicalis, Cyberlindnera jadinii, Metschnikowia pulcherrima Schwanniomyces occidentalis and Wickerhamomyces ciferii. No yeast tested could utilize all carbon sources and tolerate all inhibitors tested. These results indicate that yeast strains should be selected based on characteristics compatible with the composition of the targeted hydrolysate. Other factors to consider include the production of valuable co-products such as carotenoids, availability of genetic tools, biosafety level, and flocculation of the yeast strain. The data generated in this study will aid in aligning yeasts with compatible hydrolysates for conversion of carbohydrates to lipids to be used for biofuels and other oleochemicals. PMID:24818698

  16. Carbon source utilization and inhibitor tolerance of 45 oleaginous yeast species.

    PubMed

    Sitepu, Irnayuli; Selby, Tylan; Lin, Ting; Zhu, Shirley; Boundy-Mills, Kyria

    2014-07-01

    Conversion of lignocellulosic hydrolysates to lipids using oleaginous (high lipid) yeasts requires alignment of the hydrolysate composition with the characteristics of the yeast strain, including ability to utilize certain nutrients, ability to grow independently of costly nutrients such as vitamins, and ability to tolerate inhibitors. Some combination of these characteristics may be present in wild strains. In this study, 48 oleaginous yeast strains belonging to 45 species were tested for ability to utilize carbon sources associated with lignocellulosic hydrolysates, tolerate inhibitors, and grow in medium without supplemented vitamins. Some well-studied oleaginous yeast species, as well as some that have not been frequently utilized in research or industrial production, emerged as promising candidates for industrial use due to ability to utilize many carbon sources, including Cryptococcus aureus, Cryptococcus laurentii, Hannaella aff. zeae, Tremella encephala, and Trichosporon coremiiforme. Other species excelled in inhibitor tolerance, including Candida aff. tropicalis, Cyberlindnera jadinii, Metschnikowia pulcherrima, Schwanniomyces occidentalis and Wickerhamomyces ciferrii. No yeast tested could utilize all carbon sources and tolerate all inhibitors tested. These results indicate that yeast strains should be selected based on characteristics compatible with the composition of the targeted hydrolysate. Other factors to consider include the production of valuable co-products such as carotenoids, availability of genetic tools, biosafety level, and flocculation of the yeast strain. The data generated in this study will aid in aligning yeasts with compatible hydrolysates for conversion of carbohydrates to lipids to be used for biofuels and other oleochemicals. PMID:24818698

  17. Butyric acid fermentation from pretreated and hydrolysed wheat straw by an adapted Clostridium tyrobutyricum strain

    PubMed Central

    Baroi, G N; Baumann, I; Westermann, P; Gavala, H N

    2015-01-01

    Butyric acid is a valuable building-block for the production of chemicals and materials and nowadays it is produced exclusively from petroleum. The aim of this study was to develop a suitable and robust strain of Clostridium tyrobutyricum that produces butyric acid at a high yield and selectivity from lignocellulosic biomasses. Pretreated (by wet explosion) and enzymatically hydrolysed wheat straw (PHWS), rich in C6 and C5 sugars (71.6 and 55.4 g l−1 of glucose and xylose respectively), was used as substrate. After one year of serial selections, an adapted strain of C. tyrobutyricum was developed. The adapted strain was able to grow in 80% (v v−1) PHWS without addition of yeast extract compared with an initial tolerance to less than 10% PHWS and was able to ferment both glucose and xylose. It is noticeable that the adapted C. tyrobutyricum strain was characterized by a high yield and selectivity to butyric acid. Specifically, the butyric acid yield at 60–80% PHWS lie between 0.37 and 0.46 g g−1 of sugar, while the selectivity for butyric acid was as high as 0.9–1.0 g g−1 of acid. Moreover, the strain exhibited a robust response in regards to growth and product profile at pH 6 and 7. PMID:26230610

  18. Effects of a preparation of combined glutathione-enriched yeast and rice embryo/soybean extracts on ethanol hangover.

    PubMed

    Lee, Heon-Sik; Song, Jugyeong; Kim, Tae Myoung; Joo, Seong Soo; Park, Dongsun; Jeon, Jeong Hee; Shin, Sunhee; Park, Hyoung Kook; Lee, Won Kyung; Ly, Sun Yung; Kim, Mee Ree; Lee, Do Ik; Kim, Yun-Bae

    2009-12-01

    The effects of a preparation of combined glutathione-enriched yeast (GEY) and rice embryo/soybean (RES) extracts (20:1), GEY/RES, on experimentally induced ethanol hangover were investigated in male Sprague-Dawley rats. To evaluate the preventive effects on hangover, rats were orally administered GEY/RES (50/2.5, 100/5, or 200/10 mg/kg) for 2 weeks. At 30 minutes after the final treatment, they were challenged with 3 mL/kg ethanol (15 mL of 20% in water/kg). The blood concentrations of alcohol and acetaldehyde were analyzed up to 7 hours postchallenge. Hepatic mRNA expression levels of alcohol-metabolizing enzymes, alcohol dehydrogenase (ADH), cytochrome P450 type 2E1 (CYP2E1), and aldehyde dehydrogenase (ALDH), were determined by real-time polymerase chain reaction. Additional rats were challenged with ethanol and, 60 minutes later, administered GEY/RES to evaluate alcohol clearance. Pretreatment with GEY/RES for 2 weeks reduced the blood concentrations of alcohol and acetaldehyde in a dose-dependent manner, lowering by 29.5% and 54.6% at the highest dose (200/10 mg/kg), respectively. The expressions of mRNAs for ADH and ALDH, the major alcohol-metabolizing enzymes, were markedly increased in the livers of rats administered GEY/RES for 2 weeks, whereas CYP2E1 mRNA was suppressed. Postchallenge treatment with GEY/RES enhanced the alcohol clearance rate by lowering blood concentrations of alcohol and acetaldehyde by 24% and 26.6%, respectively, for the highest dose group. GEY/RES remarkably eliminated 2,2-diphenyl-1-picrylhydrazyl hydrate radical and FeCl(3)-mediated lipid peroxidation in vitro and attenuated hepatic lipid accumulation following ethanol administration in vivo. Therefore, it is suggested that GEY/RES reduces the blood concentrations of alcohol and acetaldehyde not only by modulating alcohol-metabolizing enzymes, but also by exerting its antioxidant activity, and that GEY/RES could be a promising candidate for improvements of alcoholic hangover. PMID:20041794

  19. Establishment of Salvia castanea Diels f. tomentosa Stib. hairy root cultures and the promotion of tanshinone accumulation and gene expression with Ag(+), methyl jasmonate, and yeast extract elicitation.

    PubMed

    Li, Bo; Wang, Bangqing; Li, Hongyan; Peng, Liang; Ru, Mei; Liang, Zongsuo; Yan, Xijun; Zhu, Yonghong

    2016-01-01

    Salvia castanea Diels f. tomentosa Stib. is an endemic medicinal plant distributed in China, and the notably high content of tanshinone IIA in the root is proven effective for the therapy of heart diseases. Hairy root induction of this Salvia species was inoculated with Agrobacterium rhizogenes strain ATCC 15834. Transformed hairy root was cultured in 6,7-V liquid medium for growth kinetics assessment and elicitation. An S curve was present in the hairy root cultures based on the fresh and dry weights with an interval of 3 days. An optimum concentration of the applied elicitors (15 μM Ag(+), 200 μM methyl jasmonate, and 200 mg l(-1) yeast extract elicitor) benefitted both the growth status and tanshinone accumulation in the hairy root cultures. Tanshinone IIA contents were mostly stimulated 1.8-fold and 1.99-fold compared with the control by Ag(+) and methyl jasmonate elicitation, respectively. Yeast extract dramatically enhanced dry mass accumulation, while it promoted cryptotanshinone content of 2.84 ± 0.33 mg g(-1) dry weight at most in the hairy root cultures. Selected elicitors diversely influenced tanshinone accumulation in the time courses of hairy root cultures within 7 days. Furthermore, transcripts of selected genes in the tanshinone biosynthetic pathway were remarkably upregulated with elicitation. Yeast extract elicitor heightened 13.9-fold of isopentenyl diphosphate isomerase expression level at 12 h, while it increased 16.7-fold of geranylgeranyl diphosphate synthase transcript at 24 h compared with that of the control, which was more effective than Ag(+) and methyl jasmonate. This study provided a convenient hairy root culture system of S. castanea Diels f. tomentosa Stib. for tanshinone production for the first time. PMID:25783026

  20. Cyclin B-Cdk1 Kinase Stimulates ORC- and Cdc6-Independent Steps of Semiconservative Plasmid Replication in Yeast Nuclear Extracts

    PubMed Central

    Duncker, Bernard P.; Pasero, Philippe; Braguglia, Diego; Heun, Patrick; Weinreich, Michael; Gasser, Susan M.

    1999-01-01

    Nuclear extracts from Saccharomyces cerevisiae cells synchronized in S phase support the semiconservative replication of supercoiled plasmids in vitro. We examined the dependence of this reaction on the prereplicative complex that assembles at yeast origins and on S-phase kinases that trigger initiation in vivo. We found that replication in nuclear extracts initiates independently of the origin recognition complex (ORC), Cdc6p, and an autonomously replicating sequence (ARS) consensus. Nonetheless, quantitative density gradient analysis showed that S- and M-phase nuclear extracts consistently promote semiconservative DNA replication more efficiently than G1-phase extracts. The observed semiconservative replication is compromised in S-phase nuclear extracts deficient for the Cdk1 kinase (Cdc28p) but not in extracts deficient for the Cdc7p kinase. In a cdc4-1 G1-phase extract, which accumulates high levels of the specific Clb-Cdk1 inhibitor p40SIC1, very low levels of semiconservative DNA replication were detected. Recombinant Clb5-Cdc28 restores replication in a cdc28-4 S-phase extract yet fails to do so in the cdc4-1 G1-phase extract. In contrast, the addition of recombinant Xenopus CycB-Cdc2, which is not sensitive to inhibition by p40SIC1, restores efficient replication to both extracts. Our results suggest that in addition to its well-characterized role in regulating the origin-specific prereplication complex, the Clb-Cdk1 complex modulates the efficiency of the replication machinery itself. PMID:9891057

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

    PubMed

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

    2014-01-01

    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

  2. Sunflower protein hydrolysates reduce cholesterol micellar solubility.

    PubMed

    Megías, Cristina; Pedroche, Justo; Del Mar Yust, María; Alaiz, Manuel; Girón-Calle, Julio; Millán, Francisco; Vioque, Javier

    2009-06-01

    Plant protein hydrolysates are a source of bioactive peptides. There are peptides that decrease the micellar cholesterol solubility from bile acids and therefore may reduce in vivo cholesterol absorption. The presence of these peptides in sunflower protein hydrolysates has been studied. Sunflower protein hydrolysates produced with alcalase plus flavourzyme or with pepsin plus pancreatin inhibited in some degree the cholesterol incorporation to micelles. Protein hydrolysates generated after 30 min of hydrolysis with alcalase, and after 30 min of hydrolysis with pepsin, were the inhibitoriest of the cholesterol incorporation to micelles. The average amino acid hydrophobicity of inhibitory peptides in cholesterol micelles was higher than the observed in the corresponding protein hydrolysates. This high hydrophobicity probably favours their inclusion in the lipid micelles. In vivo, this inhibition may translate in a decrease of cholesterol absorption. Reported results show that a combination of different characteristics such as peptide size or hydrophobicity may be responsible of the inhibitory activity of generated peptides. PMID:19205886

  3. Effect of Mechanically Deboned Chicken Meat Hydrolysates on the Physicochemical Properties of Imitation Fish Paste

    PubMed Central

    Jin, Sang-Keun; Go, Gwang-woong; Jung, Eun-Young; Lim, Hyun-Jung; Yang, Han-Sul; Park, Jae-Hong

    2014-01-01

    This study investigated on the effects of adding mechanically deboned chicken meat (MDCM) hydrolysates on the quality properties of imitation fish paste (IFP) during storage. IFP was prepared from Alaska Pollack, spent laying hens surimi and protein hydrolysates which were enzymatically extracted from MDCM. The study was designed as a 3×4 factorial design with three MDCM hydrolysate content groups (0%, 0.4%, and 0.8%) and four storage times (0, 2, 4, and 6 weeks). Addition of MDCM hydrolysates increased crude fat content but lowered water content (p<0.05). The breaking force of IFP, an indicator of gel formation, increased in treated groups compared to control (p<0.05). Angiotensin I-converting enzyme (ACE) activity was inhibited and free radical scavenging activity increased with increasing MDCM hydrolysate content (p<0.05). In conclusion, the addition of MDCM to IFP improves gel characteristics. Additionally, protein hydrolysates from MDCM serve as a potential source of ACE inhibiting peptides. PMID:25049933

  4. Antioxidant and antihypertensive activity of gelatin hydrolysate from Nile tilapia skin.

    PubMed

    Choonpicharn, Sadabpong; Jaturasitha, Sanchai; Rakariyatham, Nuansri; Suree, Nuttee; Niamsup, Hataichanoke

    2015-05-01

    Fish skin, a by-product from fish processing industries, still contains a significant amount of protein-rich material. Gelatin was extracted from Nile tilapia skin with the yield 20.77 ± 0.80 % wet weight. Gelatin was then separately hydrolyzed by proteases, including bromelain, papain, trypsin, flavourzyme, alcalase and neutrase. Low molecular weight gelatin hydrolysate (<10 kDa) has a great potential as an antioxidant agent. Flavourzyme hydrolysate has potent activity on ABTS radical scavenging (1,413.61 ± 88.74 μg trolox/mg protein) and also inhibits the oxidation of linoleic acid at a high level (59.74 ± 16.57 % inhibition). The greatest reducing power is in alcalase hydrolysate (4.951 ± 1.577 mM trolox/mg protein). While, bromelain hydrolysate has the highest ferrous ion chelating activity (86.895 ± 0.061 %). Evaluation of the angiotensin-I-converting enzyme's inhibitory activity indicates that all hydrolysates have great potency as an antihypertensive agent. All studied tilapia skin gelatin hydrolysates contain potent antioxidant and anti-hypertensive effects. PMID:25892821

  5. Effect of mechanically deboned chicken meat hydrolysates on the physicochemical properties of imitation fish paste.

    PubMed

    Jin, Sang-Keun; Go, Gwang-Woong; Jung, Eun-Young; Lim, Hyun-Jung; Yang, Han-Sul; Park, Jae-Hong

    2014-01-01

    This study investigated on the effects of adding mechanically deboned chicken meat (MDCM) hydrolysates on the quality properties of imitation fish paste (IFP) during storage. IFP was prepared from Alaska Pollack, spent laying hens surimi and protein hydrolysates which were enzymatically extracted from MDCM. The study was designed as a 3×4 factorial design with three MDCM hydrolysate content groups (0%, 0.4%, and 0.8%) and four storage times (0, 2, 4, and 6 weeks). Addition of MDCM hydrolysates increased crude fat content but lowered water content (p<0.05). The breaking force of IFP, an indicator of gel formation, increased in treated groups compared to control (p<0.05). Angiotensin I-converting enzyme (ACE) activity was inhibited and free radical scavenging activity increased with increasing MDCM hydrolysate content (p<0.05). In conclusion, the addition of MDCM to IFP improves gel characteristics. Additionally, protein hydrolysates from MDCM serve as a potential source of ACE inhibiting peptides. PMID:25049933

  6. Hydrolysed formula and risk of allergic or autoimmune disease: systematic review and meta-analysis

    PubMed Central

    Ierodiakonou, Despo; Khan, Tasnia; Chivinge, Jennifer; Robinson, Zoe; Geoghegan, Natalie; Jarrold, Katharine; Afxentiou, Thalia; Reeves, Tim; Cunha, Sergio; Trivella, Marialena; Garcia-Larsen, Vanessa; Leonardi-Bee, Jo

    2016-01-01

    Objective To determine whether feeding infants with hydrolysed formula reduces their risk of allergic or autoimmune disease. Design Systematic review and meta-analysis, as part of a series of systematic reviews commissioned by the UK Food Standards Agency to inform guidelines on infant feeding. Two authors selected studies by consensus, independently extracted data, and assessed the quality of included studies using the Cochrane risk of bias tool. Data sources Medline, Embase, Web of Science, CENTRAL, and LILACS searched between January 1946 and April 2015. Eligibility criteria for selecting studies Prospective intervention trials of hydrolysed cows’ milk formula compared with another hydrolysed formula, human breast milk, or a standard cows’ milk formula, which reported on allergic or autoimmune disease or allergic sensitisation. Results 37 eligible intervention trials of hydrolysed formula were identified, including over 19 000 participants. There was evidence of conflict of interest and high or unclear risk of bias in most studies of allergic outcomes and evidence of publication bias for studies of eczema and wheeze. Overall there was no consistent evidence that partially or extensively hydrolysed formulas reduce risk of allergic or autoimmune outcomes in infants at high pre-existing risk of these outcomes. Odds ratios for eczema at age 0-4, compared with standard cows’ milk formula, were 0.84 (95% confidence interval 0.67 to 1.07; I2=30%) for partially hydrolysed formula; 0.55 (0.28 to 1.09; I2=74%) for extensively hydrolysed casein based formula; and 1.12 (0.88 to 1.42; I2=0%) for extensively hydrolysed whey based formula. There was no evidence to support the health claim approved by the US Food and Drug Administration that a partially hydrolysed formula could reduce the risk of eczema nor the conclusion of the Cochrane review that hydrolysed formula could prevent allergy to cows’ milk. Conclusion These findings do not support current guidelines that recommend the use of hydrolysed formula to prevent allergic disease in high risk infants. Review registration PROSPERO CRD42013004252. PMID:26956579

  7. Radiation hydrolysate of tuna cooking juice with enhanced antioxidant properties

    NASA Astrophysics Data System (ADS)

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

    2012-08-01

    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 μM to 1930 μM and IC50 on superoxide anion was decreased from 3.91 μg/mL to 1.29 μg/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.

  8. Actinopyga lecanora Hydrolysates as Natural Antibacterial Agents

    PubMed Central

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

    2012-01-01

    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

  9. Characterization of flavor of whey protein hydrolysates.

    PubMed

    Leksrisompong, Pattarin P; Miracle, R Evan; Drake, Maryanne

    2010-05-26

    Twenty-two whey protein hydrolysates (WPH) obtained from 8 major global manufacturers were characterized by instrumental analysis and descriptive sensory analysis. Proximate analysis, size exclusion chromatography, and two different degrees of hydrolysis (DH) analytical methods were also conducted. WPH were evaluated by a trained descriptive sensory panel, and volatile compounds were extracted by solid phase microextraction (SPME) followed by gas chromatography-mass spectrometry (GC-MS) and gas chromatography-olfactometry (GC-O). Eleven representative WPH were selected, and 15 aroma active compounds were quantified by GC-MS via the generation of external standard curves. Potato/brothy, malty, and animal flavors and bitter taste were key distinguishing sensory attributes of WPH. Correlations between bitter taste intensity, degree of hydrolysis (using both methods), and concentration of different molecular weight peptides were documented, with high DH samples having high bitter taste intensity and a high concentration of low molecular weight peptides and vice versa. The four aroma-active compounds out of 40 detected by GC-O present at the highest concentration and with consistently high odor activity values in WPH were Strecker derived products, dimethyl sulfide (DMS), 3-methyl butanal, 2-methyl butanal, and methional. Orthonasal thresholds of WPH were lower (p < 0.05) than basic taste thresholds suggesting that aromatics and bitter taste are both crucial to control in WPH food applications. PMID:20415487

  10. Applications of Protein Hydrolysates in Biotechnology

    NASA Astrophysics Data System (ADS)

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

    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.

  11. Biofunctional properties of enzymatic squid meat hydrolysate.

    PubMed

    Choi, Joon Hyuk; Kim, Kyung-Tae; Kim, Sang Moo

    2015-03-01

    Squid is one of the most important commercial fishes in the world and is mainly utilized or consumed as sliced raw fish or as processed products. The biofunctional activities of enzymatic squid meat hydrolysate were determined to develop value-added products. Enzymatic squid hydrolysate manufactured by Alcalase effectively quenched 1,1-diphenyl-2-picrylhydrazyl radical, hydroxyl radical, and hydrogen peroxide radical with IC50 values of 311, 3,410, and 111.5 μg/mL, respectively. Angiotensin I-converting enzyme inhibitory activity of squid hydrolysate was strong with an IC50 value of 145.1 μg/mL, while tyrosinase inhibitory activity with an IC50 value of 4.72 mg/mL was moderately low. Overall, squid meat hydrolysate can be used in food or cosmetic industries as a bioactive ingredient and possibly be used in the manufacture of seasoning, bread, noodle, or cosmetics. PMID:25866752

  12. Biofunctional Properties of Enzymatic Squid Meat Hydrolysate

    PubMed Central

    Choi, Joon Hyuk; Kim, Kyung-Tae; Kim, Sang Moo

    2015-01-01

    Squid is one of the most important commercial fishes in the world and is mainly utilized or consumed as sliced raw fish or as processed products. The biofunctional activities of enzymatic squid meat hydrolysate were determined to develop value-added products. Enzymatic squid hydrolysate manufactured by Alcalase effectively quenched 1,1-diphenyl-2-picrylhydrazyl radical, hydroxyl radical, and hydrogen peroxide radical with IC50 values of 311, 3,410, and 111.5 μg/mL, respectively. Angiotensin I-converting enzyme inhibitory activity of squid hydrolysate was strong with an IC50 value of 145.1 μg/mL, while tyrosinase inhibitory activity with an IC50 value of 4.72 mg/mL was moderately low. Overall, squid meat hydrolysate can be used in food or cosmetic industries as a bioactive ingredient and possibly be used in the manufacture of seasoning, bread, noodle, or cosmetics. PMID:25866752

  13. Could yeast infections impair recovery from mental illness? A case study using micronutrients and olive leaf extract for the treatment of ADHD and depression.

    PubMed

    Rucklidge, Julia J

    2013-01-01

    Micronutrients are increasingly used to treat psychiatric disorders including attention-deficit/hyperactivity disorder (ADHD), mood disorders, stress, and anxiety. However, a number of factors influence optimal response and absorption of nutrients, including the health of the gut, particularly the presence of yeast infections, such as Candida. As part of a wider investigation into the impact of micronutrients on psychiatric symptoms, many participants who experienced a yeast infection during their treatment showed a diminished response to the micronutrients. One case was followed systematically over a period of 3 y with documentation of deterioration in psychiatric symptoms (ADHD and mood) when infected with Candida and then symptom improvement following successful treatment of the infection with olive leaf extract (OLE) and probiotics. This case outlines that micronutrient treatment might be severely compromised by infections such as Candida and may highlight the importance of gut health when treating psychiatric disorders with nutrients. Given the role that inflammation can play in absorption of nutrients, it was hypothesized that the infection was impairing absorption of the micronutrients. PMID:23784606

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

    DOEpatents

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

    2013-09-10

    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.

  15. Contribution of PRS3, RPB4 and ZWF1 to the resistance of industrial Saccharomyces cerevisiae CCUG53310 and PE-2 strains to lignocellulosic hydrolysate-derived inhibitors.

    PubMed

    Cunha, Joana T; Aguiar, Tatiana Q; Romaní, Aloia; Oliveira, Carla; Domingues, Lucília

    2015-09-01

    PRS3, RPB4 and ZWF1 were previously identified as key genes for yeast tolerance to lignocellulose-derived inhibitors. To better understand their contribution to yeast resistance to the multiple stresses occurring during lignocellulosic hydrolysate fermentations, we overexpressed these genes in two industrial Saccharomyces cerevisiae strains, CCUG53310 and PE-2, and evaluated their impact on the fermentation of Eucalyptus globulus wood and corn cob hydrolysates. PRS3 overexpression improved the fermentation rate (up to 32%) and productivity (up to 48%) in different hydrolysates. ZWF1 and RPB4 overexpression did not improve the fermentation performance, but their increased expression in the presence of acetic acid, furfural and hydroxymethylfurfural was found to contribute to yeast adaptation to these inhibitors. This study expands our understanding about the molecular mechanisms involved in industrial yeast tolerance to the stresses occurring during lignocellulosic bioethanol production and highlights the importance of selecting appropriate strain backgrounds/hydrolysates combinations when addressing further improvement of these processes. PMID:25974617

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

    PubMed

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

    2014-04-01

    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 β-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 β-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 μg 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

  17. Improvement of D-Ribose Production from Corn Starch Hydrolysate by a Transketolase-Deficient Strain Bacillus subtilis UJS0717.

    PubMed

    Wei, Zhuan; Zhou, Jue; Sun, WenJing; Cui, FengJie; Xu, QinHua; Liu, ChangFeng

    2015-01-01

    D-Ribose is a five-carbon sugar and generally used as an energy source to improve athletic performance and the ability. The culture conditions for maximum D-ribose production performance from cheap raw material corn starch hydrolysate were improved by using one-factor-at-a-time experiments and a three-level Box-Behnken factorial design. The optimal fermentation parameters were obtained as 36°C culture temperature, 10% inoculum volume, and 7.0 initial pH. The mathematical model was then developed to show the effect of each medium composition and their interactions on the production of D-ribose and estimated that the optimized D-ribose production performance with the concentration of 62.13 g/L, yield of 0.40 g/g, and volumetric productivity of 0.86 g/L·h could be obtained when the medium compositions were set as 157 g/L glucose, 21 g/L corn steep liquor, 3.2 g/L (NH4)2SO4, 1 g/L yeast extract, 0.05 g/L MnSO4·H2O, and 20 g/L CaCO3. These findings indicated the D-ribose production performance was significantly improved compared to that under original conditions. PMID:26759810

  18. Improvement of D-Ribose Production from Corn Starch Hydrolysate by a Transketolase-Deficient Strain Bacillus subtilis UJS0717

    PubMed Central

    Wei, Zhuan; Zhou, Jue; Sun, WenJing; Cui, FengJie; Xu, QinHua; Liu, ChangFeng

    2015-01-01

    D-Ribose is a five-carbon sugar and generally used as an energy source to improve athletic performance and the ability. The culture conditions for maximum D-ribose production performance from cheap raw material corn starch hydrolysate were improved by using one-factor-at-a-time experiments and a three-level Box-Behnken factorial design. The optimal fermentation parameters were obtained as 36°C culture temperature, 10% inoculum volume, and 7.0 initial pH. The mathematical model was then developed to show the effect of each medium composition and their interactions on the production of D-ribose and estimated that the optimized D-ribose production performance with the concentration of 62.13 g/L, yield of 0.40 g/g, and volumetric productivity of 0.86 g/L·h could be obtained when the medium compositions were set as 157 g/L glucose, 21 g/L corn steep liquor, 3.2 g/L (NH4)2SO4, 1 g/L yeast extract, 0.05 g/L MnSO4·H2O, and 20 g/L CaCO3. These findings indicated the D-ribose production performance was significantly improved compared to that under original conditions. PMID:26759810

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

    SciTech Connect

    Rivard, C.J.; Engel, R.E.; Nagle, N.J.

    1996-12-31

    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.

  20. Influence of autochthonous lactic acid bacteria and enzymatic yeast extracts on the microbiological, biochemical and sensorial properties of Lben generic products.

    PubMed

    Mangia, Nicoletta P; Garau, Giovanni; Murgia, Marco A; Bennani, Abdelmajid; Deiana, Pietrino

    2014-05-01

    In this study we identified Lactococcus lactis subsp. lactis, Lc. lactis subsp. lactis biovar diacetylactis, Kluyveromices lactis and Saccharomyces cerevisiae as the dominant microorganisms of traditional Moroccan acid-alcoholic fermented milk named Lben. The low pH (3·8±0·3), lactose (16·8±3·4 mg/l) and lactic acid (8·16±0·6 mg/l) content indicated that a strong fermentation occurred in the traditional product which was also characterised by the substantial presence of ethanol and typical volatile carbonyl compounds (i.e., acetoin, diacetyl and acetaldehyde). Microbiological analyses of experimental Lben manufactured with selected strains (isolated from the traditional product) of Lc. lactis subsp. lactis and Lc. lactis subsp. lactis biovar. diacetylactis alone (batch A) and in combination with enzymatic extract of a K. lactis strain (batch B) indicated a good effectiveness of the starters employed (∼1010 CFU/g of lactococci after 8 h of incubation) and a significant effect of the yeast enzyme extract on lactococci viability. Despite slight changes in the physicochemical characteristics of the two Lben during the 15 d storage period, volatile compounds (i.e. ethanol, acetaldehyde, diacetyl and acetoin) were consistently higher in batch B. Moreover, sensorial analysis performed after 15 d of storage, highlighted higher odour and flavour intensity, vegetable odour and viscosity in batch B while batch A displayed higher astringency. PMID:24642233

  1. State of the Art Manufacturing of Protein Hydrolysates

    NASA Astrophysics Data System (ADS)

    Pasupuleti, Vijai K.; Braun, Steven

    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.

  2. Protein enrichment of an Opuntia ficus-indica cladode hydrolysate by cultivation of Candida utilis and Kluyveromyces marxianus

    PubMed Central

    Akanni, Gabriel B; du Preez, James C; Steyn, Laurinda; Kilian, Stephanus G

    2015-01-01

    BACKGROUND The cladodes of Opuntia ficus-indica (prickly pear cactus) have a low protein content; for use as a balanced feed, supplementation with other protein sources is therefore desirable. We investigated protein enrichment by cultivation of the yeasts Candida utilis and Kluyveromyces marxianus in an enzymatic hydrolysate of the cladode biomass. RESULTS Dilute acid pretreatment and enzymatic hydrolysis of sun-dried cladodes resulted in a hydrolysate containing (per litre) 45.5 g glucose, 6.3 g xylose, 9.1 g galactose, 10.8 g arabinose and 9.6 g fructose. Even though K. marxianus had a much higher growth rate and utilized l-arabinose and d-galactose more completely than C. utilis, its biomass yield coefficient was lower due to ethanol and ethyl acetate production despite aerobic cultivation. Yeast cultivation more than doubled the protein content of the hydrolysate, with an essential amino acid profile superior to sorghum and millet grains. CONCLUSIONS This K. marxianus strain was weakly Crabtree positive. Despite its low biomass yield, its performance compared well with C. utilis. This is the first report showing that the protein content and quality of O. ficus-indica cladode biomass could substantially be improved by yeast cultivation, including a comparative evaluation of C. utilis and K. marxianus. © 2014 The Authors. Journal of the Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. PMID:25371280

  3. Methane production from acid hydrolysates of Agave tequilana bagasse: evaluation of hydrolysis conditions and methane yield.

    PubMed

    Arreola-Vargas, Jorge; Ojeda-Castillo, Valeria; Snell-Castro, Raúl; Corona-González, Rosa Isela; Alatriste-Mondragón, Felipe; Méndez-Acosta, Hugo O

    2015-04-01

    Evaluation of diluted acid hydrolysis for sugar extraction from cooked and uncooked Agave tequilana bagasse and feasibility of using the hydrolysates as substrate for methane production, with and without nutrient addition, in anaerobic sequencing batch reactors (AnSBR) were studied. Results showed that the hydrolysis over the cooked bagasse was more effective for sugar extraction at the studied conditions. Total sugars concentration in the cooked and uncooked bagasse hydrolysates were 27.9 g/L and 18.7 g/L, respectively. However, 5-hydroxymethylfurfural was detected in the cooked bagasse hydrolysate, and therefore, the uncooked bagasse hydrolysate was selected as substrate for methane production. Interestingly, results showed that the AnSBR operated without nutrient addition obtained a constant methane production (0.26 L CH4/g COD), whereas the AnSBR operated with nutrient addition presented a gradual methane suppression. Molecular analyses suggested that methane suppression in the experiment with nutrient addition was due to a negative effect over the archaeal/bacterial ratio. PMID:25647030

  4. Oyster (Crassostrea gigas) Hydrolysates Produced on a Plant Scale Have Antitumor Activity and Immunostimulating Effects in BALB/c Mice

    PubMed Central

    Wang, Yu-Kai; He, Hai-Lun; Wang, Guo-Fan; Wu, Hao; Zhou, Bai-Cheng; Chen, Xiu-Lan; Zhang, Yu-Zhong

    2010-01-01

    Oyster extracts have been reported to have many bioactive peptides. But the function of oyster peptides produced by proteolysis is still unknown. In this study, the oligopeptide-enriched hydrolysates from oyster (Crassostrea gigas) were produced using the protease from Bacillus sp. SM98011 at laboratory level, and scaled up to pilot (100 L) and plant (1,000 L) levels with the same conditions. And the antitumor activity and immunostimulating effects of the oyster hydrolysates in BALB/c mice were investigated. The growth of transplantable sarcoma-S180 was obviously inhibited in a dose-dependent manner in BALB/c mice given the oyster hydrolysates. Mice receiving 0.25, 0.5 and 1 mg/g of body weight by oral gavage had 6.8%, 30.6% and 48% less tumor growth, respectively. Concurrently, the weight coefficients of the thymus and the spleen, the activity of natural killer (NK) cells, the spleen proliferation of lymphocytes and the phagocytic rate of macrophages in S180-bearing mice significantly increased after administration of the oyster hydrolysates. These results demonstrated that oyster hydrolysates produced strong immunostimulating effects in mice, which might result in its antitumor activity. The antitumor and immunostimulating effects of oyster hydrolysates prepared in this study reveal its potential for tumor therapy and as a dietary supplement with immunostimulatory activity. PMID:20390104

  5. Fit-for-purpose quenching and extraction protocols for metabolic profiling of yeast using chromatography-mass spectrometry platforms.

    PubMed

    Winder, Catherine L; Dunn, Warwick B

    2011-01-01

    Metabolomics involves the investigation of the intracellular (endometabolome) and extracellular (exometabolome) pools of metabolites in biological systems. Methods to sample the exometabolome and to quench metabolism and extract intracellular metabolites for the model eukaryote Saccharomyces cerevisiae are presented here. These methods have been developed and validated to provide a fit-for-purpose protocol for global analyses of the S. cerevisiae metabolome. The protocol allows the extraction of a wide variety of metabolite classes and provides reproducible results to allow relative and semi-quantitative comparisons between samples of different origin. For exometabolome studies, fast sampling and separation of cells by syringe filtration is recommended. For endometabolome studies, fast quenching of intracellular metabolism is performed using a 60:40 (v/v) methanol:aqueous ammonium hydrogen carbonate solution at -48 °C. Extraction of intracellular metabolites is performed using multiple freeze/thaw cycles in a 60:40 (v/v) methanol:water solution at temperatures lower than 0 °C. PMID:21863491

  6. Electricity generation from rapeseed straw hydrolysates using microbial fuel cells.

    PubMed

    Jablonska, Milena A; Rybarczyk, Maria K; Lieder, Marek

    2016-05-01

    Rapeseed straw is an attractive fuel material for microbial fuel cells (MFCs) due to its high content of carbohydrates (more than 60% carbohydrates). This study has demonstrated that reducing sugars can be efficiently extracted from raw rapeseed straw by combination of hydrothermal pretreatment and enzymatic hydrolysis followed by utilization as a fuel in two-chamber MFCs for electrical power generation. The most efficient method of saccharification of this lignocellulosic biomass (17%) turned out hydrothermal pretreatment followed by enzymatic hydrolysis. Electricity was produced using hydrolysate concentrations up to 150mg/dm(3). The power density reached 54mW/m(2), while CEs ranged from 60% to 10%, corresponding to the initial reducing sugar concentrations of 10-150mg/dm(3). The COD degradation rates based on charge calculation increased from 0.445gCOD/m(2)/d for the hydrolysate obtained with the microwave treatment to 0.602gCOD/m(2)/d for the most efficient combination of hydrothermal treatment followed by enzymatic hydrolysis. PMID:26930033

  7. Hydrolysates of lignocellulosic materials for biohydrogen production

    PubMed Central

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

    2013-01-01

    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

  8. Antimicrobial and antiviral activity of hydrolysable tannins.

    PubMed

    Buzzini, Pietro; Arapitsas, Panagiotis; Goretti, Marta; Branda, Eva; Turchetti, Benedetta; Pinelli, Patrizia; Ieri, F; Romani, Annalisa

    2008-10-01

    Hydrolysable tannins (HTs), secondary metabolites widely distributed in the plant kingdom, are generally multiple esters of gallic acid with glucose. HTs have been shown to be effective antagonists against viruses, bacteria and eukaryotic microorganisms. The present review examines the antimicrobial and antiviral activity of HTs, the mechanism(s) of action, and some structure-activity relationships. PMID:18855732

  9. Antimicrobial and antiviral activity of hydrolysable tannins.

    TOXLINE Toxicology Bibliographic Information

    Buzzini P; Arapitsas P; Goretti M; Branda E; Turchetti B; Pinelli P; Ieri F; Romani A

    2008-10-01

    Hydrolysable tannins (HTs), secondary metabolites widely distributed in the plant kingdom, are generally multiple esters of gallic acid with glucose. HTs have been shown to be effective antagonists against viruses, bacteria and eukaryotic microorganisms. The present review examines the antimicrobial and antiviral activity of HTs, the mechanism(s) of action, and some structure-activity relationships.

  10. Isotopologue analysis of sugar phosphates in yeast cell extracts by gas chromatography chemical ionization time-of-flight mass spectrometry.

    PubMed

    Chu, Dinh Binh; Troyer, Christina; Mairinger, Teresa; Ortmayr, Karin; Neubauer, Stefan; Koellensperger, Gunda; Hann, Stephan

    2015-04-01

    Metabolic flux analysis is based on the measurement of isotopologue ratios. In this work, a new GC-MS-based method was introduced enabling accurate determination of isotopologue distributions of sugar phosphates in cell extracts. A GC-TOFMS procedure was developed involving a two-step online derivatization (ethoximation followed by trimethylsilylation) offering high mass resolution, high mass accuracy and the potential of retrospective data analysis typical for TOFMS. The information loss due to fragmentation intrinsic for isotopologue analysis by electron ionization could be overcome by chemical ionization with methane. A thorough optimization regarding pressure of the reaction gas, emission current, electron energy and temperature of the ion source was carried out. For a substantial panel of sugar phosphates both of the glycolysis and the pentose phosphate pathway, sensitive determination of the protonated intact molecular ions together with low abundance fragment ions was successfully achieved. The developed method was evaluated for analysis of Pichia pastoris cell extracts. The measured isotopologue ratios were in the range of 55:1-2:1. The comparison of the experimental isotopologue fractions with the theoretical fractions was excellent, revealing a maximum bias of 4.6% and an average bias of 1.4%. PMID:25673246

  11. Xylulokinase Overexpression in Two Strains of Saccharomyces cerevisiae Also Expressing Xylose Reductase and Xylitol Dehydrogenase and Its Effect on Fermentation of Xylose and Lignocellulosic Hydrolysate

    PubMed Central

    Johansson, Björn; Christensson, Camilla; Hobley, Timothy; Hahn-Hägerdal, Bärbel

    2001-01-01

    Fermentation of the pentose sugar xylose to ethanol in lignocellulosic biomass would make bioethanol production economically more competitive. Saccharomyces cerevisiae, an efficient ethanol producer, can utilize xylose only when expressing the heterologous genes XYL1 (xylose reductase) and XYL2 (xylitol dehydrogenase). Xylose reductase and xylitol dehydrogenase convert xylose to its isomer xylulose. The gene XKS1 encodes the xylulose-phosphorylating enzyme xylulokinase. In this study, we determined the effect of XKS1 overexpression on two different S. cerevisiae host strains, H158 and CEN.PK, also expressing XYL1 and XYL2. H158 has been previously used as a host strain for the construction of recombinant xylose-utilizing S. cerevisiae strains. CEN.PK is a new strain specifically developed to serve as a host strain for the development of metabolic engineering strategies. Fermentation was carried out in defined and complex media containing a hexose and pentose sugar mixture or a birch wood lignocellulosic hydrolysate. XKS1 overexpression increased the ethanol yield by a factor of 2 and reduced the xylitol yield by 70 to 100% and the final acetate concentrations by 50 to 100%. However, XKS1 overexpression reduced the total xylose consumption by half for CEN.PK and to as little as one-fifth for H158. Yeast extract and peptone partly restored sugar consumption in hydrolysate medium. CEN.PK consumed more xylose but produced more xylitol than H158 and thus gave lower ethanol yields on consumed xylose. The results demonstrate that strain background and modulation of XKS1 expression are important for generating an efficient xylose-fermenting recombinant strain of S. cerevisiae. PMID:11526030

  12. Comparing the sugar profiles and primary structures of alkali-extracted water-soluble polysaccharides in cell wall between the yeast and mycelial phases from Tremella fuciformis.

    PubMed

    Zhu, Hanyu; Yuan, Yuan; Liu, Juan; Zheng, Liesheng; Chen, Liguo; Ma, Aimin

    2016-05-01

    To gain insights into dimorphism, cell wall polysaccharides from Tremella fuciformis strains were obtained from alkali-extracted water-soluble fractions PTF-M38 (from the mycelial form), PTF-Y3 and PTF-Y8 (from the yeast form) of T. fuciformis strains were used to gain some insights into dimorphism study. Their chemical properties and structural features were investigated using gel permeation chromatography, gas chromatography, UV and IR spectrophotometry and Congo red binding reactions. The results indicated that the backbones of PTF-M38, PTF-Y3 and PTF-Y8 were configured with α-linkages with average molecular weights of 1.24, 1.08, and 1.19 kDa, respectively. PTF-M38 was mainly composed of xylose, mannose, glucose, and galactose in a ratio of 1:1.47:0.48:0.34, while PTF-Y3 and PTF-Y8 were mainly composed of xylose, mannose and glucose in a ratio of 1:1.65:4.06 and 1:1.21:0.44, respectively. The sugar profiles of PTF-M38, PTF-Y3 and PTF-Y8 were also established for further comparison. These profiles showed that all three polysaccharides contained the same sugars but in different ratios, and the carbon sources (xylose, mannose, glucose, and galactose) affected the sugar ratios within the polysaccharides. PMID:27095457

  13. An economic approach to efficient isotope labeling in insect cells using homemade 15N-, 13C- and 2H-labeled yeast extracts.

    PubMed

    Opitz, Christian; Isogai, Shin; Grzesiek, Stephan

    2015-07-01

    Heterologous expression of proteins in insect cells is frequently used for crystallographic structural studies due to the high yields even for challenging proteins requiring the eukaryotic protein processing capabilities of the host. However for NMR studies, the need for isotope labeling poses extreme challenges in eukaryotic hosts. Here, we describe a robust method to achieve uniform protein (15)N and (13)C labeling of up to 90 % in baculovirus-infected insect cells. The approach is based on the production of labeled yeast extract, which is subsequently supplemented to insect cell growth media. The method also allows deuteration at levels of >60 % without decrease in expression yield. The economic implementation of the labeling procedures into a standard structural biology laboratory environment is described in a step-by-step protocol. Applications are demonstrated for a variety of NMR experiments using the Abelson kinase domain, GFP, and the beta-1 adrenergic receptor as examples. Deuterated expression of the latter provides spectra of very high quality of a eukaryotic G-protein coupled receptor. PMID:26070442

  14. p33-Independent Activation of a Truncated p92 RNA-Dependent RNA Polymerase of Tomato Bushy Stunt Virus in Yeast Cell-Free Extract

    PubMed Central

    Pogany, Judit

    2012-01-01

    Plus-stranded RNA viruses replicate in membrane-bound structures containing the viral replicase complex (VRC). A key component of the VRC is the virally encoded RNA-dependent RNA polymerase (RdRp), which should be activated and incorporated into the VRC after its translation. To study the activation of the RdRp of Tomato bushy stunt virus (TBSV), a small tombusvirus of plants, we used N-terminal truncated recombinant RdRp, which supported RNA synthesis in a cell-free yeast extract-based assay. The truncated RdRp required a cis-acting RNA replication element and soluble host factors, while unlike the full-length TBSV RdRp, the truncated RdRp did not need the viral p33 replication cofactor or cellular membranes for RNA synthesis. Interestingly, the truncated RdRp used 3?-terminal extension for initiation and terminated prematurely at an internal cis-acting element. However, the truncated RdRp could perform de novo initiation on a TBSV plus-strand RNA template in the presence of the p33 replication cofactor, cellular membranes, and soluble host proteins. Altogether, the data obtained with the truncated RdRp indicate that this RdRp still requires activation, but with the participation of fewer components than with the full-length RdRp, making it suitable for future studies on dissection of the RdRp activation mechanism. PMID:22933278

  15. Comparison of the sequestering properties of yeast cell wall extract and hydrated sodium calcium aluminosilicate in three in vitro models accounting for the animal physiological bioavailability of zearalenone.

    PubMed

    Yiannikouris, A; Kettunen, H; Apajalahti, J; Pennala, E; Moran, C A

    2013-01-01

    The sequestration/inactivation of the oestrogenic mycotoxin zearalenone (ZEA) by two adsorbents--yeast cell wall extract (YCW) and hydrated sodium calcium aluminosilicate (HSCAS)--was studied in three laboratory models: (1) an in vitro model was adapted from referenced methods to test for the sequestrant sorption capabilities under buffer conditions at two pH values using liquid chromatography coupled to a fluorescence detector for toxin quantification; (2) a second in vitro model was used to evaluate the sequestrant sorption stability according to pH variations and using ³H-labelled ZEA at low toxin concentration; and (3) an original, ex vivo Ussing chamber model was developed to further understand the transfer of ZEA through intestinal tissue and the impact of each sequestrant on the mycotoxin bioavailability of ³H-labelled ZEA. YCW was a more efficient ZEA adsorbent than HSCAS in all three models, except under very acidic conditions (pH 2.5 or 3.0). The Ussing chamber model offered a novel, ex vivo, alternative method for understanding the effect of sequestrant on the bioavailability of ZEA. The results showed that compared with HSCAS, YCW was more efficient in sequestering ZEA and that it reduced the accumulation of ZEA in the intestinal tissue by 40% (p < 0.001). PMID:23844575

  16. Comparison of a novel MPN method against the yeast extract agar (YEA) pour plate method for the enumeration of heterotrophic bacteria from drinking water.

    PubMed

    Sartory, David P; Gu, Haoyi; Chen, Chun-Ming

    2008-07-01

    This study compared the Quanti-Disc most probable number (MPN) test for heterotrophic bacteria from drinking water with the widely used yeast extract agar (YEA) pour plate method. The Quanti-Disc test module contains 50 reaction wells in which a medium has been pre-deposited. The medium contains a suite of three fluorogenic enzyme substrates selected for the detection of enzymes expressed widely by heterotrophic bacteria. The MPN of heterotrophic bacteria is calculated from the number of fluorescing reaction wells after incubation of a sample. Quanti-Disc and the YEA pour plate method were compared according to guidance on comparing methods given in United Kingdom national guidance and ISO 17994:2004. The two methods were also challenged with reference strains and isolates of heterotrophic bacteria from drinking water. This indicated that heterotrophic bacteria commonly encountered in drinking water are detected by both the YEA pour plate method and Quanti-Disc. Analysis of data from split water samples (723 for 37 degrees C tests and 872 for 22 degrees C tests) from nine geographically diverse laboratories in England and Wales demonstrated that the Quanti-Disc method is equivalent to the YEA pour plate method for the analysis of heterotrophic bacteria from drinking and similar waters at 37 degrees C, and superior to YEA for the analysis at 22 degrees C. The Quanti-Disc method is a simple and efficient alternative method for the enumeration of heterotrophic bacteria from drinking water. PMID:18534656

  17. Long-Term n-Caproic Acid Production from Yeast-Fermentation Beer in an Anaerobic Bioreactor with Continuous Product Extraction.

    PubMed

    Ge, Shijian; Usack, Joseph G; Spirito, Catherine M; Angenent, Largus T

    2015-07-01

    Multifunctional reactor microbiomes can elongate short-chain carboxylic acids (SCCAs) to medium-chain carboxylic acids (MCCAs), such as n-caproic acid. However, it is unclear whether this microbiome biotechnology platform is stable enough during long operating periods to consistently produce MCCAs. During a period of 550 days, we improved the operating conditions of an anaerobic bioreactor for the conversion of complex yeast-fermentation beer from the corn kernel-to-ethanol industry into primarily n-caproic acid. We incorporated and improved in-line, membrane liquid-liquid extraction to prevent inhibition due to undissociated MCCAs at a pH of 5.5 and circumvented the addition of methanogenic inhibitors. The microbiome accomplished several functions, including hydrolysis and acidogenesis of complex organic compounds and sugars into SCCAs, subsequent chain elongation with undistilled ethanol in beer, and hydrogenotrophic methanogenesis. The methane yield was 2.40 ± 0.52% based on COD and was limited by the availability of carbon dioxide. We achieved an average n-caproate production rate of 3.38 ± 0.42 g L(-1) d(-1) (7.52 ± 0.94 g COD L(-1) d(-1)) with an n-caproate yield of 70.3 ± 8.81% and an n-caproate/ethanol ratio of 1.19 ± 0.15 based on COD for a period of ∼55 days. The maximum production rate was achieved by increasing the organic loading rates in tandem with elevating the capacity of the extraction system and a change in the complex feedstock batch. PMID:25941741

  18. Fecal microbial communities of healthy adult dogs fed raw meat-based diets with or without inulin or yeast cell wall extracts as assessed by 454 pyrosequencing.

    PubMed

    Beloshapka, Alison N; Dowd, Scot E; Suchodolski, Jan S; Steiner, Jörg M; Duclos, Laura; Swanson, Kelly S

    2013-06-01

    Our objective was to determine the effects of feeding raw meat-based diets with or without inulin or yeast cell wall extract (YCW) on fecal microbial communities of dogs using 454 pyrosequencing. Six healthy female adult beagles (5.5 ± 0.5 years; 8.5 ± 0.5 kg) were randomly assigned to six test diets using a Latin square design: (1) beef control; (2) beef + 1.4% inulin; (3) beef + 1.4% YCW; (4) chicken control; (5) chicken + 1.4% inulin; and (6) chicken + 1.4% YCW. Following 14 days of adaptation, fresh fecal samples were collected on day 15 or day 16 of each period. Fecal genomic DNA was extracted and used to create 16S rRNA gene amplicons, which were subjected to 454 pyrosequencing and qPCR. Predominant fecal bacterial phyla included Fusobacteria, Firmicutes, Bacteroidetes, and Proteobacteria. Beef-based diets increased (P < 0.05) Escherichia, but decreased (P < 0.05) Anaerobiospirillum vs. chicken-based diets. Inulin decreased (P < 0.05) Enterobacteriaceae. Inulin increased (P < 0.05) Megamonas vs. control. Inulin also decreased (P < 0.05) Escherichia vs. YCW. qPCR data showed that YCW increased (P < 0.05) Bifidobacterium vs. inulin and control and inulin increased (P < 0.05) Lactobacillus vs. YCW. Although a few changes in fecal microbiota were observed with inulin or YCW consumption, a strong prebiotic effect was not observed. PMID:23360519

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

    PubMed

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

    2012-02-15

    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 25C 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

  20. Physicochemical and bitterness properties of enzymatic pea protein hydrolysates.

    PubMed

    Humiski, L M; Aluko, R E

    2007-10-01

    The effects of different proteolytic treatments on the physiochemical and bitterness properties of pea protein hydrolysates were investigated. A commercial pea protein isolate was digested using each of 5 different proteases to produce protein hydrolysates with varying properties. After 4 h of enzyme digestion, samples were clarified by centrifugation followed by desalting of the supernatant with a 1000 Da membrane; the retentates were then freeze-dried. Alcalase and Flavourzymetrade mark produced protein hydrolysates with significantly higher (P < 0.05) degree of hydrolysis when compared to the other proteases. Flavourzyme, papain, and alcalase produced hydrolysates that contained the highest levels of aromatic amino acids, while trypsin hydrolysate had the highest levels of lysine and arginine. Papain hydrolysate contained high molecular weight peptides (10 to 178 kDa) while hydrolysates from the other 4 proteases contained predominantly low molecular weight peptides (hydrolysate was significantly (P < 0.05) the highest while alcalase and trypsin hydrolysates were the lowest. Inhibition of angiotensin converting enzyme (ACE) activity was significantly higher (P < 0.05) for papain hydrolysate while Flavourzyme hydrolysate had the least inhibitory activity. Sensory analysis showed that the alcalase hydrolysate was the most bitter while papain and alpha-chymotrypsin hydrolysates were the least. Among the 5 enzymes used in this study, papain and alpha-chymotrypsin appear to be the most desirable for producing high quality pea protein hydrolysates because of the low bitterness scores combined with a high level of angiotensin converting enzyme inhibition and moderate free radical scavenging activity. PMID:17995627

  1. Beta-glucan-depleted, glycopeptide-rich extracts from Brewer's and Baker's yeast (Saccharomyces cerevisiae) lower interferon-gamma production by stimulated human blood cells in vitro.

    PubMed

    Williams, Roderick; Dias, Daniel A; Jayasinghe, Nirupama; Roessner, Ute; Bennett, Louise E

    2016-04-15

    Regulation of the human immune system requires controlled pro- and anti-inflammatory responses for host defence against infection and disease states. Yeasts (Saccharomyces cerevisiae), as used in brewing and baking, are mostly known for ability to stimulate the human immune-system predominantly reflecting the pro-inflammatory cell wall β-glucans. However, in this study, using food-compatible processing methods, glycopeptide-enriched and β-glucan-depleted products were each prepared from Brewer's and Baker's yeasts, which suppressed production of interferon-γ (IFN-γ) in human whole blood cell assay, signifying that anti-inflammatory factors are also present in yeast. Anti-inflammatory bioactivities of products prepared from Brewer's and Baker's yeast were compared with the commercial yeast product, Epicor®. While unfractionated Epicor was inactive, the C18 resin-binding fractions of Brewer's and Baker's yeast products and Epicor dose-dependently lowered IFN-γ, demonstrating that Epicor also contained both pro-inflammatory (β-glucans) and anti-inflammatory components. Anti-inflammatory activity was attributed to C18 resin-binding species glyco-peptides in Epicor and experimental yeast products. This study demonstrated that pro- and anti-inflammatory factors could be resolved and enriched in yeasts by suitable processing, with potential to improve specific activities. PMID:26617014

  2. A new beta-glucosidase producing yeast for lower-cost cellulosic ethanol production from xylose-extracted corncob residues by simultaneous saccharification and fermentation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Conventional cellulose-to-ethanol conversion by simultaneous saccharification and fermentation (SSF)requires enzymatic saccharification using both cellulase and ß-glucosidase allowing cellulose utilization by common ethanologenic yeast. Here we report a new yeast strain of Clavispora NRRL Y-50464 th...

  3. Quantification of astaxanthin in shrimp waste hydrolysate by HPLC.

    PubMed

    López-Cervantes, J; Sánchez-Machado, D I; Gutiérrez-Coronado, M A; Ríos-Vázquez, N J

    2006-10-01

    In the present study, a simple and rapid reversed-phase HPLC method for the determination of astaxanthin in shrimp waste hydrolysate has been developed and validated. The analytical procedure involves the direct extraction of astaxanthin from the lipid fraction with methanol. The analytical column, SS Exil ODS, was operated at 25C. The mobile phase consisted of a mixture of water:methanol:dichloromethane:acetonitrile (4.5:28:22:45.5 v/v/v/v) at a flow rate of 1.0 mL/min. Detection and identification were performed using a photodiode array detector (lambda(detection) = 476 nm). The proposed HPLC method showed adequate linearity, repeatability and accuracy. PMID:16802328

  4. A systematic review of xuezhikang, an extract from red yeast rice, for coronary heart disease complicated by dyslipidemia.

    PubMed

    Shang, Qinghua; Liu, Zhaolan; Chen, Keji; Xu, Hao; Liu, Jianping

    2012-01-01

    Objective. This systematic review aims to evaluate the benefit and side effect of Xuezhikang for coronary heart disease (CHD) complicated by dyslipidemia. Methods. All randomized clinical trials (RCTs) with Xuezhikang as a treatment for CHD combined with dyslipidemia were considered for inclusion. Data extraction and analyses and quality assessment were conducted according to the Cochrane standards. Results. We included 22 randomized trials. Xuezhikang showed significant benefit on the incidence of all-cause deaths, CHD deaths, myocardial infarction, and revascularization as compared with placebo based on conventional treatment for CHD. It remarkably lowered total cholesterol (TC), triglyceride (TG), and low-density lipoprotein-cholesterol (LDL-C) as compared with the placebo or inositol nicotinate group, which was similar to statins group. Xuezhikang also raised high-density lipoprotein cholesterol (HDL-C) compared to placebo or no intervention, which was similar to Inositol nicotinate and slightly inferior to statins. The incidence of adverse events did not differ between the Xuezhikang and control group. Conclusions. Xuezhikang showed a comprehensive lipid-regulating effect and was safe and effective in reducing cardiovascular events in CHD patients complicated by dyslipidemia. However, more rigorous trials with high quality are needed to give high level of evidence. PMID:22567033

  5. Oil Production from Yarrowia lipolytica Po1g Using Rice Bran Hydrolysate

    PubMed Central

    Tsigie, Yeshitila Asteraye; Wang, Chun-Yuan; Kasim, Novy S.; Diem, Quy-Do; Huynh, Lien-Huong; Ho, Quoc-Phong; Truong, Chi-Thanh; Ju, Yi-Hsu

    2012-01-01

    The purpose of this study was to produce microbial oil from Yarrowia lipolytica Po1g grown in defatted rice bran hydrolysate. After removing oil from rice bran by Soxhlet extraction, the bran is subjected to acid hydrolysis with various sulfuric acid concentrations (1–4% v/v), reaction times (1–8 h), and reaction temperatures (60–120°C). The optimal conditions for maximum total sugar production from the hydrolysate were found to be 3% sulfuric acid at 90°C for 6 h. Glucose was the predominant sugar (43.20 ± 0.28 g/L) followed by xylose (4.93 ± 0.03 g/L) and arabinose (2.09 ± 0.01 g/L). The hydrolysate was subsequently detoxified by neutralization to reduce the amount of inhibitors such as 5-hydroxymethylfurfural (HMF) and furfural to increase its potential as a medium for culturing Y. lipolytica Po1g. Dry cell mass and lipid content of Y. lipolytica Po1g grown in detoxified defatted rice bran hydrolysate (DRBH) under optimum conditions were 10.75 g/L and 48.02%, respectively. PMID:22496604

  6. Counting Yeast.

    ERIC Educational Resources Information Center

    Bealer, Jonathan; Welton, Briana

    1998-01-01

    Describes changes to a traditional study of population in yeast colonies. Changes to the procedures include: (1) only one culture per student team; (2) cultures are inoculated only once; and (3) the same tube is sampled daily. (DDR)

  7. 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, ...

  8. In vitro exposure of Penicillium mycotoxins with or without a modified yeast cell wall extract (mYCW) on bovine macrophages (BoMacs).

    PubMed

    Oh, Se-Young; Quinton, V Margaret; Boermans, Herman J; Swamy, H V L N; Karrow, Niel A

    2015-11-01

    Penicillium mycotoxins (PMs) are contaminants that are frequently found in grain or crop-based silage for animal feed. Previously, we have characterized the potential immunotoxicity of the following PMs: citrinin (CIT), ochratoxin A (OTA), patulin (PAT), mycophenolic acid (MPA), and penicillic acid (PA) by using a bovine macrophage cell line (BoMacs). In the present study, cell proliferation was used as a bioassay endpoint to evaluate the efficacy of a modified yeast cell wall extract (mYCW), for preventing PM toxicity under various in vitro conditions such as the following: pH (3, 5, 7), incubation time (1, 2, 4, 6 h), percentage of mYCW (0.05, 0.1, 0.2, 0.5, 1.0 %), and PM concentration. mYCW was most effective in preventing the toxicity of 12.88 and 25.8 μM OTA at pH 3.0 (p < 0.0001), regardless of incubation time (p < 0.0001) and the percentage of mYCW (p < 0.0001). An incubation time of 6 h (p < 0.05) or 0.5 and 1.0 % mYCW (p < 0.0001) significantly improved the efficacy of mYCW for preventing CIT toxicity. In contrast, 0.5 and 1.0 % of mYCW appeared to exacerbate the PAT toxicity (p < 0. 0001). This effect on PAT toxicity was constantly observed with higher PAT concentrations, and it reached significance at a concentration of 0.70 μM (p < 0.0001). mYCW had no effect on PA toxicity. These results suggest that mYCW may reduce OTA toxicity and, to some extent, CIT toxicity at pH 3.0. Although PAT toxicity was increased by mYCW treatment, PAT is readily degraded during heat treatment and may therefore be dealt with using other preventative measures. PMID:26358170

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

    PubMed Central

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

    2015-01-01

    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. Pre-culturing 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

  10. Detoxification of lignocellulosic hydrolysates using sodium borohydride.

    PubMed

    Cavka, Adnan; Jönsson, Leif J

    2013-05-01

    Addition of sodium borohydride to a lignocellulose hydrolysate of Norway spruce affected the fermentability when cellulosic ethanol was produced using Saccharomyces cerevisiae. Treatment of the hydrolysate with borohydride improved the ethanol yield on consumed sugar from 0.09 to 0.31 g/g, the balanced ethanol yield from 0.02 to 0.30 g/g, and the ethanol productivity from 0.05 to 0.57 g/(L×h). Treatment of a sugarcane bagasse hydrolysate gave similar results, and the experiments indicate that sodium borohydride is suitable for chemical in situ detoxification. The model inhibitors coniferyl aldehyde, p-benzoquinone, 2,6-dimethoxybenzoquinone, and furfural were efficiently reduced by treatment with sodium borohydride, even under mild reaction conditions (20 °C and pH 6.0). While addition of sodium dithionite to pretreatment liquid from spruce improved enzymatic hydrolysis of cellulose, addition of sodium borohydride did not. This result indicates that the strong hydrophilicity resulting from sulfonation of inhibitors by dithionite treatment was particularly important for alleviating enzyme inhibition. PMID:23567704

  11. Physiological response of Saccharomyces cerevisiae to weak acids present in lignocellulosic hydrolysate.

    PubMed

    Guo, Zhongpeng; Olsson, Lisbeth

    2014-12-01

    Weak acids are present in lignocellulosic hydrolysate as potential inhibitors that can hamper the use of this renewable resource for fuel and chemical production. To study the effects of weak acids on yeast growth, physiological investigations were carried out in batch cultures using glucose as carbon source in the presence of acetic, formic, levulinic, and vanillic acid at three different concentrations at pH 5.0. The results showed that acids at moderate concentrations can stimulate the glycolytic flux, while higher levels of acid slow down the glycolytic flux for both aerobically and anaerobically grown yeast cells. In particular, the flux distribution between respiratory and fermentative growth was adjusted to achieve an optimal ATP generation to allow a maintained energy level as high as it is in nonstressed cells grown exponentially on glucose under aerobic conditions. In addition, yeast cells exposed to acids suffered from severe reactive oxygen species stress and depletion of reduced glutathione commensurate with exhaustion of the total glutathione pool. Furthermore, a higher cellular trehalose content was observed as compared to control cultivations, and this trehalose probably acts to enhance a number of stress tolerances of the yeast. PMID:25331461

  12. Iron-Binding Capacity of Defatted Rice Bran Hydrolysate and Bioavailability of Iron in Caco-2 Cells.

    PubMed

    Foong, Lian-Chee; Imam, Mustapha Umar; Ismail, Maznah

    2015-10-21

    The present study was aimed at utilizing defatted rice bran (DRB) protein as an iron-binding peptide to enhance iron uptake in humans. DRB samples were treated with Alcalase and Flavourzyme, and the total extractable peptides were determined. Furthermore, the iron-binding capacities of the DRB protein hydrolysates were determined, whereas iron bioavailability studies were conducted using an in vitro digestion and absorption model (Caco-2 cells). The results showed that the DRB protein hydrolysates produced by combined Alcalase and Flavourzyme hydrolysis had the best iron-binding capacity (83%) after 90 min of hydrolysis. The optimal hydrolysis time to produce the best iron-uptake in Caco-2 cells was found to be 180 min. The results suggested that DRB protein hydrolysates have potent iron-binding capacities and may enhance the bioavailability of iron, hence their suitability for use as iron-fortified supplements. PMID:26435326

  13. Effect of germinated soybean protein hydrolysates on adipogenesis and adipolysis in 3T3-L1 cells.

    PubMed

    González-Espinosa de los Monteros, L A; Ramón-Gallegos, E; Torres-Torres, N; Mora-Escobedo, R

    2011-11-01

    Germination of soybeans increases the bioavailability of some nutrients. An evaluation was done to determine if germination increased the anti-adipogenic and lipolytic effects of soybean. Soybeans were germinated for 0 to 6 days and protein concentrates extracted from beans germinated at each period. Soy protein concentrates can retain notable amounts of phytochemicals with anti-adipogenic activity. For this reason, it was evaluated the effect of protein hydrolysates with and without phytochemicals in the adipocyte-like cells after 3T3-L1 (murine fibroblasts) cell line differentiation. Cell viability decreased with exposure to the germinated soybean protein hydrolysates during the differentiation stage, but not during the fibroblast or mature adipocyte stages. Adipogenesis and triglycerides accumulation were strongly inhibited by the hydrolysate from soybeans germinated for 2 days (with ethanol-soluble phytochemicals), when compared to ungerminated soybean. Adipolysis increased with exposure to hydrolysates from beans germinated for 2 days (with phytochemicals) and 5 days (without phytochemicals). Germinated soy protein hydrolysates had an effect on inhibition of lipid storage in adypocites and increasing lipolysis, which was improved by changes of the protein and increased phytochemical content due to germination. PMID:22108960

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

    PubMed

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

    2014-12-01

    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

  15. Dissecting a complex chemical stress: chemogenomic profiling of plant hydrolysates

    PubMed Central

    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; Ibáñez, Ana B; Mitchell, Valerie D; Wu, Cindy H; Hu, Ping; Hazen, Terry; Arkin, Adam P

    2013-01-01

    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

  16. Dissecting a complex chemical stress: chemogenomic profiling of plant hydrolysates.

    PubMed

    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; Ibáñez, Ana B; Mitchell, Valerie D; Wu, Cindy H; Hu, Ping; Hazen, Terry; Arkin, Adam P

    2013-01-01

    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

  17. Collagen hydrolysate based collagen/hydroxyapatite composite materials

    NASA Astrophysics Data System (ADS)

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

    2013-04-01

    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.

  18. CHARACTERIZATION OF A NOVEL ETHANOLOGENIC YEAST IN THE FERMENTATION OF SOFTWOOD LIGNOCELLULOSIC SUGARS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A novel, genetically unmodified ethanologenic yeast, integrated into the pre-hydrolysate fermentation stage of the softwood-to-ethanol bioconversion process, was identified as being capable of rapid assimilation and catabolism of all wood-derived hexose sugars (galactose, glucose, and mannose). Thi...

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

    PubMed

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

    2014-07-01

    Poly(ε-L-lysine) (ε-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 ε-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 ε-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 ε-PL and PDAP by S. albulus PD-1. PMID:24861999

  20. Growth of oleaginous Rhodotorula glutinis in an internal-loop airlift bioreactor by using lignocellulosic biomass hydrolysate as the carbon source.

    PubMed

    Yen, Hong-Wei; Chang, Jung-Tzu

    2015-05-01

    The conversion of abundant lignocellulosic biomass (LCB) to valuable compounds has become a very attractive idea recently. This study successfully used LCB (rice straw) hydrolysate as a carbon source for the cultivation of oleaginous yeast-Rhodotorula glutinis in an airlift bioreactor. The lipid content of 34.3 ± 0.6% was obtained in an airlift batch with 60 g reducing sugars/L of LCB hydrolysate at a 2 vvm aeration rate. While using LCB hydrolysate as the carbon source, oleic acid (C18:1) and linoleic acid (C18:2) were the predominant fatty acids of the microbial lipids. Using LCB hydrolysate in the airlift bioreactor at 2 vvm achieved the highest cell mass growth as compared to the agitation tank. Despite the low lipid content of the batch using LCB hydrolysate, this low cost feedstock has the potential of being adopted for the production of β-carotene instead of lipid accumulation in the airlift bioreactor for the cultivation of R. glutinis. PMID:25454603

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

    PubMed

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

    2012-08-01

    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

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

    PubMed Central

    2013-01-01

    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

  3. Enhanced ethanol production from deacetylated yellow poplar acid hydrolysate by Pichia stipitis.

    PubMed

    Cho, Dae Haeng; Shin, Soo-Jeong; Bae, Yangwon; Park, Chulhwan; Kim, Yong Hwan

    2010-07-01

    In this study, alkaline-pretreatment for the extraction of acetic acid from xylan of hemicellulose was introduced prior to concentrated acid hydrolysis of yellow poplar wood meal. Ethanol fermentability in deacetylated yellow poplar hydrolysate (DYPH) by Pichia stipitis was also investigated. The alkali-pretreatment conditions were evaluated in terms of temperature, reaction time, and alkalinity. 94% of the acetyl group in xylan of the yellow poplar hemicellulose fraction was extracted using 0.5% sodium hydroxide solution at 60 degrees C for 60 min. The cell growth and ethanol production of P. stipitis was strongly affected by acetic acid, either in synthetic medium with 7.1g/l of acetic acid added or in yellow poplar hydrolysate (YPH) containing 7.1g/l of acetic acid. On the other hand, ethanol production in DYPH was slightly higher than that of the control although cell growth decreased by 34%. In the case of DYPH, the ethanol yield, volumetric ethanol productivity, and theoretical yield percentage was 0.48 g/g, 0.40 g/lh, and 93.2%, respectively. Thus, the alkaline-pretreatment method greatly enhanced the ethanol fermentability of yellow poplar hydrolysate. PMID:19959357

  4. Identification of crucial yeast inhibitors in bio-ethanol and improvement of fermentation at high pH and high total solids.

    PubMed

    Huang, Hongzhi; Guo, Xinyan; Li, Dongmin; Liu, Mengmeng; Wu, Jiafang; Ren, Haiyu

    2011-08-01

    Compounds inhibitory to enzymatic hydrolysis and fermentation are generated from neutral steam exploded corn stover in the process of producing bio-ethanol. In this study, weak acids were identified as main yeast inhibitors, while phenols and aldehyde contribute to the inhibition to a lower degree. Main weak acids in hydrolysates are acetic acid and formic acid, for which critical levels for yeast inhibition are 6 and 4g/L, respectively. The inhibitory effect of these compounds can be greatly overcome by increasing pH of hydrolysates to 6.0-9.0, but there is a risk of bacterial contamination when fermenting at high pH. The relationship of pH, total solids of hydrolysates, fermentation and contamination was studied in detail. Results indicate that the contamination by bacteria when fermenting at high pH can be prevented effectively using hydrolysates with total solids of more than 20%. Meanwhile, ethanol yield is improved significantly. PMID:21624827

  5. 21 CFR 573.200 - Condensed animal protein hydrolysate.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Condensed animal protein hydrolysate. 573.200... (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS FOOD ADDITIVES PERMITTED IN FEED AND DRINKING WATER OF ANIMALS Food Additive Listing § 573.200 Condensed animal protein hydrolysate. (a) Identity. The...

  6. 21 CFR 573.200 - Condensed animal protein hydrolysate.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Condensed animal protein hydrolysate. 573.200... (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS FOOD ADDITIVES PERMITTED IN FEED AND DRINKING WATER OF ANIMALS Food Additive Listing § 573.200 Condensed animal protein hydrolysate. (a) Identity. The...

  7. 21 CFR 573.200 - Condensed animal protein hydrolysate.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Condensed animal protein hydrolysate. 573.200... (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS FOOD ADDITIVES PERMITTED IN FEED AND DRINKING WATER OF ANIMALS Food Additive Listing § 573.200 Condensed animal protein hydrolysate. (a) Identity. The...

  8. 21 CFR 573.200 - Condensed animal protein hydrolysate.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Condensed animal protein hydrolysate. 573.200... (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS FOOD ADDITIVES PERMITTED IN FEED AND DRINKING WATER OF ANIMALS Food Additive Listing § 573.200 Condensed animal protein hydrolysate. (a) Identity. The...

  9. 21 CFR 573.200 - Condensed animal protein hydrolysate.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Condensed animal protein hydrolysate. 573.200... (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS FOOD ADDITIVES PERMITTED IN FEED AND DRINKING WATER OF ANIMALS Food Additive Listing § 573.200 Condensed animal protein hydrolysate. (a) Identity. The...

  10. Antioxidant activities of chick embryo egg hydrolysates

    PubMed Central

    Sun, Hao; Ye, Ting; Wang, Yuntao; Wang, Ling; Chen, Yijie; Li, Bin

    2014-01-01

    Chick embryo egg hydrolysates (CEEH) were obtained by enzymatic hydrolysis of chick embryo egg in vitro-simulated gastrointestinal digestion. The antioxidant activities of CEEH were investigated by employing three in vitro assays, including the 2,2′-azinobis-(3-ethylbenzthiazoline-6-sulfonate)/1,1-diphenyl-2-picrylhydrazyl (ABTS/DPPH)/hydroxyl radical-scavenging assays. The radical-scavenging effect of CEEH (1.0 mg/mL) was in a dose-dependent manner, with the highest trolox equivalent antioxidant capacity for ABTS, DPPH, and that of hydroxyl radicals found to be 569, 2097, and 259.6 μmol/L, respectively; whereas the trolox equivalent antioxidant capacity of unhatched egg for ABTS, DPPH, and that of hydroxyl radicals were found to be 199, 993, and 226.5 μmol/L, respectively. CEEH showed stronger scavenging activity than the hydrolysates of unhatched egg against free radicals such as ABTS, DPPH, and hydroxyl radicals. The antioxidant amino acid analysis indicated that the 14-day CEEH possess more antioxidant amino acids than that of the unhatched egg. In addition, essential amino acids analysis showed that the 14-day CEEH have the highest nutritional value. Combined with the results of the amino acid profiles, CEEH were believed to have higher nutritive value in addition to antioxidant activities than the unhatched egg. PMID:24804065

  11. Affinity purification of copper chelating peptides from chickpea protein hydrolysates.

    PubMed

    Megías, Cristina; Pedroche, Justo; Yust, Maria M; Girón-Calle, Julio; Alaiz, Manuel; Millan, Francisco; Vioque, Javier

    2007-05-16

    Chickpea protein hydrolysates obtained with alcalase and flavourzyme were used for purification of copper chelating peptides by affinity chromatography using copper immobilized on solid supports. The chelating activity of purified peptides was indirectly measured by the inhibition of beta-carotene oxidation in the presence of copper. Two protein hydrolysates, obtained after 10 and 100 min of hydrolysis, were the most inhibitory of beta-carotene oxidation. Purified copper chelating peptides from these protein hydrolysates contained 19.7 and 35.1% histidine, respectively, in comparison to 2.7 and 2.6% in the protein hydrolysates. Chelating peptides from hydrolysate obtained after 10 min of hydrolysis were the most antioxidative being 8.3 times more antioxidative than the hydrolysate, while chelating peptides purified from protein hydrolysate obtained after 100 min were 3.1 times more antioxidative than its hydrolysate. However, the histidine content was higher in peptides derived from the 100 min hydrolysate (19.7 against 35.1% in 10 min hydrolysate), indicating that this amino acid is not the only factor involved in the antioxidative activity, and other factors such as peptide size or amino acid sequence are also determinant. This manuscript shows that affinity chromatography is a useful procedure for purification of copper chelating peptides. This method can be extended to other metals of interest in nutrition, such as calcium, iron, or zinc. Purified chelating peptides, in addition to their antioxidative properties, may also be useful in food mineral fortification for increasing the bioavailability of these metals. PMID:17428066

  12. Construction of killer wine yeast strain.

    PubMed

    Seki, T; Choi, E H; Ryu, D

    1985-05-01

    A double-stranded RNA plasmid which confers the superkiller phenotype was transferred into a wine yeast (Montrachet strain 522) and its leucine-requiring derivative (strain 694) by cytoduction, using the protoplast fusion technique. The killer wine yeast constructed completely suppressed the growth of killer-sensitive strains of Saccharomyces cerevisiae in yeast extract-peptone-glucose medium at pH 4.5, whereas the killer effect was somewhat decreased at pH 3.5. The wine yeast harboring the killer factor also inhibited the growth of killer-sensitive cells satisfactorily when it was grown in grape juice. PMID:16346794

  13. Role of glucose signaling in yeast metabolism

    SciTech Connect

    Dam, K. van

    1996-10-05

    The conversion of glucose to ethanol and carbon dioxide by yeast was the first biochemical pathway to be studied in detail. The initial observation that this process is catalyzed by an extract of yeast led to the discovery of enzymes and coenzymes and laid the foundation for modern biochemistry. In this article, knowledge concerning the relation between uptake of and signaling by glucose in the yeast Saccharomyces cerevisiae is reviewed and compared to the analogous process in prokaryotes. It is concluded that (much) more fundamental knowledge concerning these processes is required before rational redesign of metabolic fluxes from glucose in yeast can be achieved.

  14. The protein encoded by the rolB plant oncogene hydrolyses indole glucosides.

    PubMed Central

    Estruch, J J; Schell, J; Spena, A

    1991-01-01

    The rolB gene of Agrobacterium rhizogenes, whose expression stimulates the formation of roots by transformed plant tissues and other growth alterations in transgenic plants, codes for a beta-glucosidase able to hydrolyse indole-beta-glucosides. Indeed, we show that extracts of bacteria and/or plant tissue expressing the rolB protein hydrolyse indoxyl-beta-glucoside (plant indican). Because of the structural similarity between indoxyl-beta-glucoside and indole-3-acetyl-beta-glucoside (IAA-beta-glucoside), we propose that the physiological and developmental alterations in transgenic plants expressing the rolB gene could be the result of an increased intracellular auxin activity caused by the release of active auxins from inactive beta-glucosides. Thus two of the oncogenes carried by the T-DNA of the plant pathogen Agrobacterium rhizogenes (rolB and rolC) perturb plant growth and development by coding for beta-glucosidases with distinct specificities. Whereas the rolC beta-glucosidase releases cytokinins from their glucoside conjugates, the rolB encoded protein hydrolyses indole-beta-glucosides. The combined action of these two genes therefore is expected to modulate the intracellular concentration of two of the main growth factors active in plants. Images PMID:1915286

  15. Molecular characterization of whey protein hydrolysate fractions with ferrous chelating and enhanced iron solubility capabilities.

    PubMed

    O'Loughlin, Ian B; Kelly, Phil M; Murray, Brian A; FitzGerald, Richard J; Brodkorb, Andre

    2015-03-18

    The ferrous (Fe2+) chelating capabilities of WPI hydrolysate fractions produced via cascade membrane filtration were investigated, specifically 1 kDa permeate (P) and 30 kDa retentate (R) fractions. The 1 kDa-P possessed a Fe2+ chelating capability at 1 g L(-1) equivalent to 84.4 μM EDTA (for 30 kDa-R the value was 8.7 μM EDTA). Fourier transformed infrared (FTIR) spectroscopy was utilized to investigate the structural characteristics of hydrolysates and molecular interactions with Fe2+. Solid-phase extraction was employed to enrich for chelating activity; the most potent chelating fraction was enriched in histidine and lysine. The solubility of ferrous sulfate solutions (10 mM) over a range of pH values was significantly (P<0.05) improved in dispersions of hydrolysate fraction solutions (10 g protein L(-1)). Total iron solubility was improved by 72% in the presence of the 1 kDa-P fraction following simulated gastrointestinal digestion (SGID) compared to control FeSO4·7H2O solutions. PMID:25716093

  16. Ethanol and xylitol production by fermentation of acid hydrolysate from olive pruning with Candida tropicalis NBRC 0618.

    PubMed

    Mateo, Soledad; Puentes, Juan G; Moya, Alberto J; Sánchez, Sebastián

    2015-08-01

    Olive tree pruning biomass has been pretreated with pressurized steam, hydrolysed with hydrochloric acid, conditioned and afterwards fermented using the non-traditional yeast Candida tropicalis NBRC 0618. The main aim of this study was to analyse the influence of acid concentration on the hydrolysis process and its effect on the subsequent fermentation to produce ethanol and xylitol. From the results, it could be deduced that both total sugars and d-glucose recovery were enhanced by increasing the acid concentration tested; almost the whole hemicellulose fraction was hydrolysed when 3.77% was used. It has been observed a sequential production first of ethanol, from d-glucose, and then xylitol from d-xylose. The overall ethanol and xylitol yields ranged from 0.27 to 0.38kgkg(-1), and 0.12 to 0.23kgkg(-1) respectively, reaching the highest values in the fermentation of the hydrolysates obtained with hydrochloric acid 2.61% and 1.11%, respectively. PMID:25916261

  17. Development of xylose-fermenting yeasts for ethanol production at high acetic acid concentrations

    SciTech Connect

    Mohandas, D.V.; Whelan, D.R.; Panchal, C.J.

    1995-12-31

    Mutants resistant to comparatively high levels of acetic acid were isolated from the xylose-fermenting yeasts Candida shehatae and Pichia Stipitis by adapting these cultures to increasing concentrations of acetic acid grown in shake-flask cultures. These mutants were tested for their ability to ferment xylose in presence of high acetic acid concentrations, in acid hydrolysates of wood, and in hardwood spent sulfite liquor, and compared with their wild-type counterparts and between themselves. The P. stipitis mutant exhibited faster fermentation times, better tolerance to acid hydrolysates, and tolerance to lower pH.

  18. Method to produce succinic acid from raw hydrolysates

    DOEpatents

    Donnelly, Mark I.; Sanville-Millard, Cynthia Y.; Nghiem, Nhuan Phu

    2004-06-01

    A method for producing succinic acid from industrial-grade hydrolysates is provided, comprising supplying an organism that contains mutations for the genes ptsG, pflB, and ldhA, allowing said organism to accumulate biomass, and allowing said organism to metabolize the hydrolysate. Also provided is a bacteria mutant characterized in that it produces succinic acid from substrate contained in industrial-grade hydrolysate in a ratio of between 0.6:1 and 1.3:1 succinic acid to substrate.

  19. Co-fermentation of acetate and sugars facilitating microbial lipid production on acetate-rich biomass hydrolysates.

    PubMed

    Gong, Zhiwei; Zhou, Wenting; Shen, Hongwei; Yang, Zhonghua; Wang, Guanghui; Zuo, Zhenyu; Hou, Yali; Zhao, Zongbao K

    2016-05-01

    The process of lignocellulosic biomass routinely produces a stream that contains sugars plus various amounts of acetic acid. As acetate is known to inhibit the culture of microorganisms including oleaginous yeasts, little attention has been paid to explore lipid production on mixtures of acetate and sugars. Here we demonstrated that the yeast Cryptococcus curvatus can effectively co-ferment acetate and sugars for lipid production. When mixtures of acetate and glucose were applied, C. curvatus consumed both substrates simultaneously. Similar phenomena were also observed for acetate and xylose mixtures, as well as acetate-rich corn stover hydrolysates. More interestingly, the replacement of sugar with equal amount of acetate as carbon source afforded higher lipid titre and lipid content. The lipid products had fatty acid compositional profiles similar to those of cocoa butter, suggesting their potential for high value-added fats and biodiesel production. This co-fermentation strategy should facilitate lipid production technology from lignocelluloses. PMID:26874438

  20. Structural, thermal, functional, antioxidant & antimicrobial properties of β-d-glucan extracted from baker's yeast (Saccharomyces cereviseae)-Effect of γ-irradiation.

    PubMed

    Khan, Asma Ashraf; Gani, Adil; Masoodi, F A; Amin, Furheen; Wani, Idrees Ahmed; Khanday, Firdous Ahmad; Gani, Asir

    2016-04-20

    This study was carried out to evaluate the effect of γ-irradiation (0, 5, 10, 20, 30 & 50kGy) on the structural, functional, antioxidant and antimicrobial properties of yeast β-d-glucan. The samples were characterized by ATR-FTIR, gel permeation chromatography (GPC) and the thermal properties were studied using DSC. There was a decrease in the average molecular weight of β-d-glucan as the irradiation dose increased. The functional properties of irradiated yeast β-d-glucan were largely influenced by the action of gamma radiation like swelling power and viscosity decreases with increase in the irradiation dose while as fat binding capacity, emulsifying properties, foaming properties and bile acid binding capacity shows an increasing trend. All the antioxidant properties carried out using six different assays increased significantly (p≤0.05) in a dose dependent manner. The antibacterial activity of yeast β-d-glucan also showed an increasing trend with increase in the irradiation dose from 5 to 50kDa. PMID:26876872

  1. 21 CFR 102.22 - Protein hydrolysates.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... derived. (a) “Hydrolyzed wheat gluten,” “hydrolyzed soy protein,” and “autolyzed yeast extract” are examples of acceptable names. “Hydrolyzed casein” is also an example of an acceptable name, whereas “hydrolyzed milk protein” is not an acceptable name for this ingredient because it is not specific to...

  2. 21 CFR 102.22 - Protein hydrolysates.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... derived. (a) “Hydrolyzed wheat gluten,” “hydrolyzed soy protein,” and “autolyzed yeast extract” are examples of acceptable names. “Hydrolyzed casein” is also an example of an acceptable name, whereas “hydrolyzed milk protein” is not an acceptable name for this ingredient because it is not specific to...

  3. 21 CFR 102.22 - Protein hydrolysates.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... derived. (a) “Hydrolyzed wheat gluten,” “hydrolyzed soy protein,” and “autolyzed yeast extract” are examples of acceptable names. “Hydrolyzed casein” is also an example of an acceptable name, whereas “hydrolyzed milk protein” is not an acceptable name for this ingredient because it is not specific to...

  4. 21 CFR 102.22 - Protein hydrolysates.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... derived. (a) “Hydrolyzed wheat gluten,” “hydrolyzed soy protein,” and “autolyzed yeast extract” are examples of acceptable names. “Hydrolyzed casein” is also an example of an acceptable name, whereas “hydrolyzed milk protein” is not an acceptable name for this ingredient because it is not specific to...

  5. 21 CFR 102.22 - Protein hydrolysates.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... derived. (a) “Hydrolyzed wheat gluten,” “hydrolyzed soy protein,” and “autolyzed yeast extract” are examples of acceptable names. “Hydrolyzed casein” is also an example of an acceptable name, whereas “hydrolyzed milk protein” is not an acceptable name for this ingredient because it is not specific to...

  6. Reduction of L-phenylalanine in protein hydrolysates using L-phenylalanine ammonia-lyase from Rhodosporidium toruloides.

    PubMed

    Castaeda, Mara Teresita; Adachi, Osao; Hours, Roque Alberto

    2015-10-01

    L-Phenylalanine ammonia-lyase (PAL, EC 4.3.1.25) from Rhodosporidium toruloides was utilized to remove L-phenylalanine (L-Phe) from different commercial protein hydrolysates. A casein acid hydrolysate (CAH, L-Phe ~2.28 %) was employed as a model substrate. t-Cinnamic acid resulting from deamination of L-Phe was extracted, analyzed at ? = 290 nm, and used for PAL activity determination. Optimum reaction conditions, optimized using successive Doehlert design, were 35 mg mL(-1) of CAH and 800 mU mL(-1) of PAL, while temperature and pH were 42 C and 8.7, respectively. Reaction kinetics of PAL with CAH was determined under optimized conditions. Then, removal of L-Phe from CAH was tested. Results showed that more than 92 % of initial L-Phe was eliminated. Similar results were obtained with other protein hydrolysates. These findings demonstrate that PAL is a useful biocatalyst for L-Phe removal from protein hydrolysates, which can be evaluated as potential ingredients in foodstuffs for PKU patients. PMID:26243390

  7. Esters of serine and threonine in hydrolysates of histones and protamines, and attendant errors in amino acid analyses of proteins

    PubMed Central

    Murray, K.; Milstein, C.

    1967-01-01

    1. Partial acid hydrolysates of histones from various origins and of protamine were analysed by a two-dimensional ionophoretic procedure to reveal strongly acidic ninhydrin-positive components. 2. Histone fractions prepared by extraction with sulphuric acid gave rise to spots identified as serine O-sulphate and threonine O-sulphate. These two compounds, which were not found in hydrolysates of corresponding fractions prepared by extraction with hydrochloric acid, were artifacts. 3. Hydrolysis of proteins in the presence of traces of sulphate can lead to the formation of the O-sulphates of serine and threonine. This can cause errors, which may sometimes be serious, in amino acid analyses of proteins. 4. O-Phosphoserine was obtained in small amounts from some histone fractions and from protamine, but was undetectable in other histone fractions, notably those of lower lysine content. ImagesFig. 1.Fig. 2. PMID:5583992

  8. 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

    Zhou, Guisheng; Fu, Lei; Li, Xiaobo

    2015-03-01

    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 250 W, HAc% of 7.7%, RYR amount of 0.2 g (solvent-to-solid ratio 40 mL/g), extraction time of 50.7 min, 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

  9. Repeated-batch operation of surface-aerated fermentor for bioethanol production from the hydrolysate of seaweed Sargassum sagamianum.

    PubMed

    Yeon, Ji-Hyeon; Lee, Sang-Eun; Choi, Woon Yong; Kang, Do Hyung; Lee, Hyoen-Yong; Jung, Kyung-Hwan

    2011-03-01

    In this study, we investigated the feasibility of sustainable long-term bioethanol production from the hydrolysate of a brown seaweed, Sargassum sagamianum. Because the hydrolysate was prepared as a liquid solution using a hightemperature liquefying system, a repeated-batch operation was utilized as the operational strategy for bioethanol production. Additionally, we used surface aeration to improve bioethanol production from the hydrolysate containing C5 monosaccharides such as xylose. In this study, the C5 monosaccharide-utilizable yeast strain Pichia stipitis was used for bioethanol production. Therefore, based on this repeated-batch flask culture, we designed a surface-aerated repeated-batch fermentor culture, in which the aeration was finely controlled at 100 ml/min and delivered into the headspace of a 2.5-l fermentor. When the medium was replaced every 48 h, bioethanol was continuously produced for 200 h under repeated-batch fermentor culture, where the level of bioethanol production was about 9~10 (g/l). Additionally, the bioethanol yield based on the reducing sugar was about 0.386, which was the average value throughout four consecutive cultures and was about 74.5% of the theoretical value. In addition, the bioethanol yield based on quantitative TLC analyses of glucose and xylose was about 0.431, which was the average value throughout four consecutive cultures and was about 84.3% of theoretical value. Consequently, throughout this repeated-batch operation, we demonstrated that it was actually feasible to produce bioethanol from the hydrolysate of seaweed S. sagamianum. In addition, the approach described here is a practical strategy for commercial bioethanol production from seaweed, particularly for finely controlling aeration through surface aeration. PMID:21464605

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

    PubMed Central

    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

    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

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

    PubMed

    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

    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

  12. 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

    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

    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

  13. Engineering and two-stage evolution of a lignocellulosic hydrolysate-tolerant Saccharomyces cerevisiae strain for anaerobic fermentation of xylose from AFEX pretreated corn stover.

    PubMed

    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

    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

  14. A stereochemical investigation of the hydrolysis of cyclic AMP and the (Sp)-and (Rp)-diastereoisomers of adenosine cyclic 3':5'-phosphorothioate by bovine heart and baker's-yeast cyclic AMP phosphodiesterases.

    PubMed Central

    Jarvest, R L; Lowe, G; Baraniak, J; Stec, W J

    1982-01-01

    Bovine heart cyclic AMP phosphodiesterase, which has a requirement for Mg2+, hydrolyses cyclic AMP with inversion of configuration at the phosphorus atom, but only the (Sp)-diastereoisomer of adenosine cyclic 3':5'-phosphorothioate is hydrolysed by this enzyme. By contrast, the low-affinity yeast cyclic AMP phosphodiesterase, which contains tightly bound Zn2+, hydrolyses both the (Sp)- and the (Rp)-diastereoisomers of adenosine cyclic 3':5'-phosphorothioate, the (Rp)-diastereoisomer being the preferred substrate under V max. conditions. Both of the diastereoisomers of adenosine cyclic 3':5'-phosphorothioate, as well as cyclic AMP, are hydrolysed with inversion of configuration at the phosphorus atom by the yeast enzyme. It is proposed that, with both enzymes, the bivalent metal ion co-ordinates with the phosphate residue of the substrate, and that hydrolysis is catalysed by a direct "in-line' mechanism. PMID:6288001

  15. Hydrolysates of citrus plants stimulate melanogenesis protecting against UV-induced dermal damage.

    PubMed

    Chiang, Hsiu-Mei; Lin, Jen-Wen; Hsiao, Pei-Ling; Tsai, Shang-Yuan; Wen, Kuo-Ching

    2011-04-01

    The sun-tanning process occurs as a spontaneous response to ultraviolet (UV) irradiation. UV will induce tanning and DNA damage, processes that can lead to photoaging and skin disorders such as hyperpigmentation and cancer. The pigment melanin protects skin from UV damage; therefore, an efficient melanin-promoting suntan lotion could be highly beneficial. In this study, a process was developed to increase the content of naringenin in citrus extracts and to determine whether a higher naringenin content of citrus would induce melanogenesis. Melanin content and tyrosinase expression in mouse B16 melanoma cells were assayed after treatment with citrus plant extracts and their hydrolysates. The results indicate that hydrolysis increased the naringenin content in citrus extracts and that citrus preparations stimulated cellular melanogenesis and tyrosinase expression. It is suggested that this method is applicable to the industrial production of melanin-promoting suntan lotions with antiphotocarcinogenic properties derived from citrus rind and citrus products. PMID:20857432

  16. Assessment of extracts from red yeast rice for herb-drug interaction by in-vitro and in-vivo assays.

    PubMed

    Fung, Wai To; Subramaniam, G; Lee, Joel; Loh, Heng Meng; Leung, Pak Ho Henry

    2012-01-01

    Red yeast rice (RYR) is made by fermenting the yeast Monascus purpureus over rice. It is a source of natural red food colorants, a food garnish and a traditional medication. Results of the current study demonstrated that polar fractions of the RYR preparations contained herbal-drug interaction activity, which if left unremoved, enhanced P-glycoprotein activity and inhibited the major drug metabolizing cytochromes P450, i,e, CYP 1A2, 2C9 and 3A4. The data from Caco-2 cell absorption and animal model studies further demonstrated that the pharmacokinetic modulation effect by RYR preparations containing the polar fractions ("untreated" preparation) was greater than that from RYR preparations with the polar fractions removed ("treated" preparation). The data indicates a potential for herb-drug interactions to be present in RYR commonly sold as nutritional supplements when the polar fractions are not removed and this should be taken into consideration when RYR is consumed with medications, including verapamil. PMID:22389767

  17. Supplementation of Pork Patties with Bovine Plasma Protein Hydrolysates Augments Antioxidant Properties and Improves Quality

    PubMed Central

    Seo, Hyun-Woo

    2016-01-01

    This study investigated the effects of bovine plasma protein (PP) hydrolysates on the antioxidant and quality properties of pork patties during storage. Pork patties were divided into 4 groups: without butylated hydroxytoluene (BHT) and PP hydrolysates (control), 0.02% BHT (T1), 1% PP hydrolysates (T2), and 2% PP hydrolysates (T3). Pork patty supplemented with PP hydrolysates had higher pH values and lower weight loss during cooking than the control patties. Results showed that lightness and hardness both decreased upon the addition of PP hydrolysates. All samples containing BHT and PP hydrolysates had reduced TBARS and peroxide values during storage. In particular, 2% PP hydrolysates were more effective in delaying lipid oxidation than were the other treatments. It was concluded that treatment with 2% PP hydrolysates can enhance the acceptance of pork patty. PMID:27194928

  18. Plasmidic Expression of nemA and yafC* Increased Resistance of Ethanologenic Escherichia coli LY180 to Nonvolatile Side Products from Dilute Acid Treatment of Sugarcane Bagasse and Artificial Hydrolysate.

    PubMed

    Shi, Aiqin; Zheng, Huabao; Yomano, Lorraine P; York, Sean W; Shanmugam, Keelnatham T; Ingram, Lonnie O

    2016-01-01

    Hydrolysate-resistant Escherichia coli SL100 was previously isolated from ethanologenic LY180 after sequential transfers in AM1 medium containing a dilute acid hydrolysate of sugarcane bagasse and was used as a source of resistance genes. Many genes that affect tolerance to furfural, the most abundant inhibitor, have been described previously. To identify genes associated with inhibitors other than furfural, plasmid clones were selected in an artificial hydrolysate that had been treated with a vacuum to remove furfural. Two new resistance genes were discovered from Sau3A1 libraries of SL100 genomic DNA: nemA (N-ethylmaleimide reductase) and a putative regulatory gene containing a mutation in the coding region, yafC*. The presence of these mutations in SL100 was confirmed by sequencing. A single mutation was found in the upstream regulatory region of nemR (nemRA operon) in SL100. This mutation increased nemA activity 20-fold over that of the parent organism (LY180) in AM1 medium without hydrolysate and increased nemA mRNA levels >200-fold. Addition of hydrolysates induced nemA expression (mRNA and activity), in agreement with transcriptional control. NemA activity was stable in cell extracts (9 h, 37°C), eliminating a role for proteinase in regulation. LY180 with a plasmid expressing nemA or yafC* was more resistant to a vacuum-treated sugarcane bagasse hydrolysate and to a vacuum-treated artificial hydrolysate than LY180 with an empty-vector control. Neither gene affected furfural tolerance. The vacuum-treated hydrolysates inhibited the reduction of N-ethylmaleimide by NemA while also serving as substrates. Expression of the nemA or yafC* plasmid in LY180 doubled the rate of ethanol production from the vacuum-treated sugarcane bagasse hydrolysate. PMID:26826228

  19. Functional expression of Burkholderia cenocepacia xylose isomerase in yeast increases ethanol production from a glucose-xylose blend.

    PubMed

    de Figueiredo Vilela, Leonardo; de Mello, Vinicius Mattos; Reis, Viviane Castelo Branco; Bon, Elba Pinto da Silva; Gonalves Torres, Fernando Araripe; Neves, Bianca Cruz; Eleutherio, Elis Cristina Arajo

    2013-01-01

    This study presents results regarding the successful cloning of the bacterial xylose isomerase gene (xylA) of Burkholderia cenocepacia and its functional expression in Saccharomyces cerevisiae. The recombinant yeast showed to be competent to efficiently produce ethanol from both glucose and xylose, which are the main sugars in lignocellulosic hydrolysates. The heterologous expression of the gene xylA enabled a laboratorial yeast strain to ferment xylose anaerobically, improving ethanol production from a fermentation medium containing a glucose-xylose blend similar to that found in sugar cane bagasse hydrolysates. The insertion of xylA caused a 5-fold increase in xylose consumption, and over a 1.5-fold increase in ethanol production and yield, in comparison to that showed by the WT strain, in 24h fermentations, where it was not detected accumulation of xylitol. These findings are encouraging for further studies concerning the expression of B. cenocepacia xylA in an industrial yeast strain. PMID:23186665

  20. Physiological Importance and Mechanisms of Protein Hydrolysate Absorption

    NASA Astrophysics Data System (ADS)

    Zhanghi, Brian M.; Matthews, James C.

    Understanding opportunities to maximize the efficient digestion and assimilation by production animals of plant- and animal-derived protein products is critical for farmers, nutritionists, and feed manufacturers to sustain and expand the affordable production of high quality animal products for human consumption. The challenge to nutritionists is to match gastrointestinal tract load to existing or ­inducible digestive and absorptive capacities. The challenge to feed manufacturers is to develop products that are efficient substrates for digestion, absorption, and/or both events. Ultimately, the efficient absorption of digesta proteins depends on the mediated passage (transport) of protein hydrosylate products as dipeptides and unbound amino acids across the lumen- and blood-facing membranes of intestinal absorptive cells. Data testing the relative efficiency of supplying protein as hydrolysates or specific dipeptides versus as free amino acids, and the response of animals in several physiological states to feeding of protein hydrolysates, are presented and reviewed in this chapter. Next, data describing the transport mechanisms responsible for absorbing protein hydrolysate digestion products, and the known and putative regulation of these mechanisms by their substrates (small peptides) and hormones are presented and reviewed. Several conclusions are drawn regarding the efficient use of protein hydrolysate-based diets for particular physiological states, the economically-practical application of which likely will depend on technological advances in the manufacture of protein hydrolysate products.

  1. Microbial utilization and biopolyester synthesis of bagasse hydrolysates.

    PubMed

    Yu, Jian; Stahl, Heiko

    2008-11-01

    Cellulosic biomass is a potentially inexpensive renewable feedstock for the biorefineries of fuels, chemicals and materials. Sugarcane bagasse was pretreated in dilute acid solution under moderately severe conditions, releasing sugars and other hydrolysates including volatile organic acids, furfurals and acid soluble lignin. Utilization of the hydrolysates by an aerobic bacterium, Ralstonia eutropha, was investigated to determine if the organic inhibitors can be removed for potential recycling and reuse of the process water. Simultaneous biosynthesis of polyhydroxyalkanoates (PHAs) for the production of value-added bioplastics was also investigated. An inhibitory effect of hydrolysates on microbial activity was observed, but it could be effectively relieved by using (a) a large inoculum, (b) a diluted hydrolysate solution, and (c) a tolerant strain, or a combination of the three. The major organic inhibitors including formic acid, acetic acid, furfural and acid soluble lignin were effectively utilized and removed to low concentration levels (less than 100ppm) while at the same time, PHA biopolyesters were synthesized and accumulated to 57wt% of cell mass under appropriate C/N ratios. Poly(3-hydroxybutyrate) was the predominant biopolyester formed on the hydrolysates, but the cells could also synthesize co-polyesters that exhibit high ductility. PMID:18474421

  2. Single cell protein production from yacon extract using a highly thermosensitive and permeable mutant of the marine yeast Cryptococcus aureus G7a and its nutritive analysis.

    PubMed

    Zhao, Chun-Hai; Zhang, Tong; Chi, Zhen-Ming; Chi, Zhe; Li, Jing; Wang, Xiang-Hong

    2010-06-01

    The intracellular protein in the highly thermosensitive and permeable mutant can be easily released when they are incubated both in the low-osmolarity water and at the non-permissive temperature (usually 37 degrees C). After the mutant was grown in the yacon extract for 45 h, the crude protein content in the highly thermosensitive and permeable mutant Z114 was 59.1% and over 61% of the total protein could be released from the cells treated at 37 degrees C. The mutant cells grown in the yacon extract still contained high level of essential amino acids and other nutrients. This means that the yacon extract could be used as the medium for growth of the highly thermosensitive and permeable mutant which contained high content of crude protein. PMID:19727833

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

    NASA Astrophysics Data System (ADS)

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

    2014-09-01

    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.

  4. Detoxification of acidic catalyzed hydrolysate of Kappaphycus alvarezii (cottonii).

    PubMed

    Meinita, Maria Dyah Nur; Hong, Yong-Ki; Jeong, Gwi-Taek

    2012-01-01

    Red seaweed, Kappaphycus alvarezii, holds great promise for use in biofuel production due to its high carbohydrate content. In this study, we investigated the effect of fermentation inhibitors to the K. alvarezii hydrolysate on cell growth and ethanol fermentation. In addition, detoxification of fermentation inhibitors was performed to decrease the fermentation inhibitory effect. 5-Hydroxymethylfurfural and levulinic acid, which are liberated from acidic hydrolysis, was also observed in the hydrolysate of K. alvarezii. These compounds inhibited ethanol fermentation. In order to remove these inhibitors, activated charcoal and calcium hydroxide were introduced. The efficiency of activated charcoals was examined and over-liming was used to remove the inhibitors. Activated charcoal was found to be more effective than calcium hydroxide to remove the inhibitors. Detoxification by activated charcoal strongly improved the fermentability of dilute acid hydrolysate in the production of bioethanol from K. alvarezii with Saccharomyces cerevisiae. The optimal detoxifying conditions were found to be below an activated charcoal concentration of 5%. PMID:21909671

  5. Cellulosic Ethanol Production from Xylose-extracted Corncob Residue by SSF Using Inhibitor- and Thermal-tolerant Yeast Clavispora NRRL Y-50339

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Xylose-extracted corncob residue, a byproduct of the xylose-producing industry using corncobs, is an abundant potential energy resource for cellulosic ethanol production. Simultaneous saccharification and fermentation (SSF) is considered an ideal one-step process for conversion of lignocellulosic b...

  6. Effectiveness of casein hydrolysate feedings in infants with colic.

    PubMed

    Jakobsson, I; Lothe, L; Ley, D; Borschel, M W

    2000-01-01

    This study found that two casein hydrolysate formulas varying in composition were equally effective in managing colicky symptoms associated with protein sensitivity. Both hydrolysate formulas were associated with a significant, comparable reduction in crying duration and intensity from baseline in 15 of 22 infants with complete data. Subsequent challenge data suggest that the population studied were infants experiencing colicky symptoms due to protein sensitivity. A greater proportion of infants showed a positive reaction (> or = 1.5 h of crying/d) to the protein challenges than the placebo challenge, and crying was rated as more intense during whey and milk protein challenges. PMID:10677051

  7. Iron-chelating activity of chickpea protein hydrolysate peptides.

    PubMed

    Torres-Fuentes, Cristina; Alaiz, Manuel; Vioque, Javier

    2012-10-01

    Chickpea-chelating peptides were purified and analysed for their iron-chelating activity. These peptides were purified after affinity and gel filtration chromatography from a chickpea protein hydrolysate produced with pepsin and pancreatin. Iron-chelating activity was higher in purified peptide fractions than in the original hydrolysate. Histidine contents were positively correlated with the iron-chelating activity. Hence fractions with histidine contents above 20% showed the highest chelating activity. These results show that iron-chelating peptides are generated after chickpea protein hydrolysis with pepsin plus pancreatin. These peptides, through metal chelation, may increase iron solubility and bioavailability and improve iron absorption. PMID:25005984

  8. Vaginal Yeast Infections (For Parents)

    MedlinePlus

    ... Can I Help a Friend Who Cuts? Vaginal Yeast Infections KidsHealth > For Teens > Vaginal Yeast Infections Print ... side effect of taking antibiotics. What Is a Yeast Infection? A yeast infection is a common infection ...

  9. Assessing the potential of wild yeasts for bioethanol production.

    PubMed

    Ruyters, Stefan; Mukherjee, Vaskar; Verstrepen, Kevin J; Thevelein, Johan M; Willems, Kris A; Lievens, Bart

    2015-01-01

    Bioethanol fermentations expose yeasts to a new, complex and challenging fermentation medium with specific inhibitors and sugar mixtures depending on the type of carbon source. It is, therefore, suggested that the natural diversity of yeasts should be further exploited in order to find yeasts with good ethanol yield in stressed fermentation media. In this study, we screened more than 50 yeast isolates of which we selected five isolates with promising features. The species Candida bombi, Wickerhamomyces anomalus and Torulaspora delbrueckii showed better osmo- and hydroxymethylfurfural tolerance than Saccharomyces cerevisiae. However, S. cerevisiae isolates had the highest ethanol yield in fermentation experiments mimicking high gravity fermentations (25 % glucose) and artificial lignocellulose hydrolysates (with a myriad of inhibitors). Interestingly, among two tested S. cerevisiae strains, a wild strain isolated from an oak tree performed better than Ethanol Red, a S. cerevisiae strain which is currently commonly used in industrial bioethanol fermentations. Additionally, a W. anomalus strain isolated from sugar beet thick juice was found to have a comparable ethanol yield, but needed longer fermentation time. Other non-Saccharomyces yeasts yielded lower ethanol amounts. PMID:25413210

  10. Lignocellulosic ethanol production by starch-base industrial yeast under PEG detoxification

    NASA Astrophysics Data System (ADS)

    Liu, Xiumei; Xu, Wenjuan; Mao, Liaoyuan; Zhang, Chao; Yan, Peifang; Xu, Zhanwei; Zhang, Z. Conrad

    2016-02-01

    Cellulosic ethanol production from lignocellulosic biomass offers a sustainable solution for transition from fossil based fuels to renewable alternatives. However, a few long-standing technical challenges remain to be addressed in the development of an economically viable fermentation process from lignocellulose. Such challenges include the needs to improve yeast tolerance to toxic inhibitory compounds and to achieve high fermentation efficiency with minimum detoxification steps after a simple biomass pretreatment. Here we report an in-situ detoxification strategy by PEG exo-protection of an industrial dry yeast (starch-base). The exo-protected yeast cells displayed remarkably boosted vitality with high tolerance to toxic inhibitory compounds, and with largely improved ethanol productivity from crude hydrolysate derived from a pretreated lignocellulose. The PEG chemical exo-protection makes the industrial S. cerevisiae yeast directly applicable for the production of cellulosic ethanol with substantially improved productivity and yield, without of the need to use genetically modified microorganisms.

  11. Lignocellulosic ethanol production by starch-base industrial yeast under PEG detoxification.

    PubMed

    Liu, Xiumei; Xu, Wenjuan; Mao, Liaoyuan; Zhang, Chao; Yan, Peifang; Xu, Zhanwei; Zhang, Z Conrad

    2016-01-01

    Cellulosic ethanol production from lignocellulosic biomass offers a sustainable solution for transition from fossil based fuels to renewable alternatives. However, a few long-standing technical challenges remain to be addressed in the development of an economically viable fermentation process from lignocellulose. Such challenges include the needs to improve yeast tolerance to toxic inhibitory compounds and to achieve high fermentation efficiency with minimum detoxification steps after a simple biomass pretreatment. Here we report an in-situ detoxification strategy by PEG exo-protection of an industrial dry yeast (starch-base). The exo-protected yeast cells displayed remarkably boosted vitality with high tolerance to toxic inhibitory compounds, and with largely improved ethanol productivity from crude hydrolysate derived from a pretreated lignocellulose. The PEG chemical exo-protection makes the industrial S. cerevisiae yeast directly applicable for the production of cellulosic ethanol with substantially improved productivity and yield, without of the need to use genetically modified microorganisms. PMID:26837707

  12. Lignocellulosic ethanol production by starch-base industrial yeast under PEG detoxification

    PubMed Central

    Liu, Xiumei; Xu, Wenjuan; Mao, Liaoyuan; Zhang, Chao; Yan, Peifang; Xu, Zhanwei; Zhang, Z. Conrad

    2016-01-01

    Cellulosic ethanol production from lignocellulosic biomass offers a sustainable solution for transition from fossil based fuels to renewable alternatives. However, a few long-standing technical challenges remain to be addressed in the development of an economically viable fermentation process from lignocellulose. Such challenges include the needs to improve yeast tolerance to toxic inhibitory compounds and to achieve high fermentation efficiency with minimum detoxification steps after a simple biomass pretreatment. Here we report an in-situ detoxification strategy by PEG exo-protection of an industrial dry yeast (starch-base). The exo-protected yeast cells displayed remarkably boosted vitality with high tolerance to toxic inhibitory compounds, and with largely improved ethanol productivity from crude hydrolysate derived from a pretreated lignocellulose. The PEG chemical exo-protection makes the industrial S. cerevisiae yeast directly applicable for the production of cellulosic ethanol with substantially improved productivity and yield, without of the need to use genetically modified microorganisms. PMID:26837707

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

    PubMed

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

    2002-08-01

    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

  14. Yeast based sensors.

    PubMed

    Shimomura-Shimizu, Mifumi; Karube, Isao

    2010-01-01

    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. PMID:20087724

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

    PubMed Central

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

    2009-01-01

    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

  16. Glycyl endopeptidase from papaya latex: partial purification and use for production of fish gelatin hydrolysate.

    PubMed

    Karnjanapratum, Supatra; Benjakul, Soottawat

    2014-12-15

    An aqueous two-phase system (ATPS) in combination with ammonium sulphate ((NH4)2SO4) precipitation was applied to fractionate glycyl endopeptidase from the papaya latex of Red Lady and Khack Dum cultivars. ATPS containing polyethylene glycol (PEG 2000 and 6000) and salts ((NH4)2SO4 and MgSO4) at different concentrations were used. Glycyl endopeptidase with high purification fold (PF) and yield was found in the salt-rich bottom phase of ATPS with 10%PEG 6000-10% (NH4)2SO4. When ATPS fraction from Red Lady cultivar was further precipitated with 40-60% saturation of (NH4)2SO4, PF of 2.1-fold with 80.23% yield was obtained. Almost all offensive odorous compounds, particularly benzyl isothiocyanate, were removed from partially purified glycyl endopeptidase (PPGE). The fish gelatin hydrolysates prepared using PPGE showed higher ABTS radical scavenging activity and less odour, compared with those of crude extract (CE). Thus antioxidative gelatin hydrolysate with negligible undesirable odour could be prepared with the aid of PPGE. PMID:25038693

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

    NASA Astrophysics Data System (ADS)

    Kuthi, Fatin Afifah Binti Ahmad; Badri, Khairiah Haji

    2014-09-01

    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.

  18. Multifunctional peptides derived from an egg yolk protein hydrolysate: isolation and characterization.

    PubMed

    Zambrowicz, Aleksandra; Pokora, Marta; Setner, Bartosz; D?browska, Anna; Szo?tysik, Marek; Babij, Konrad; Szewczuk, Zbigniew; Trziszka, Tadeusz; Lubec, Gert; Chrzanowska, Jzefa

    2015-02-01

    An egg yolk protein by-product following ethanol extraction of phospholipids (YP) was hydrolyzed with pepsin to produce and identify novel peptides that revealed antioxidant, ACE inhibitory and antidiabetic (?-glucosidase and DPP-IV inhibitory) activities. The peptic hydrolysate of YP was fractionated by ion-exchange chromatography and reversed-phase high-pressure liquid chromatography. Isolated peptides were identified using mass spectrometry (MALDI-ToF) and the Mascot Search Results database. Four peptides of MW ranging from 1,210.62 to 1,677.88 Da corresponded to the fragments of Apolipoprotein B (YINQMPQKSRE; YINQMPQKSREA), Vitellogenin-2 (VTGRFAGHPAAQ) and Apovitellenin-1 (YIEAVNKVSPRAGQF). These peptides were chemically synthesized and showed antioxidant, ACE inhibitory or/and antidiabetic activities. Peptide YIEAVNKVSPRAGQF exerted the strongest ACE inhibitory activity, with IC50 = 9.4 g/mL. The peptide YINQMPQKSRE showed the strongest DPPH free radical scavenging and DPP-IV inhibitory activities and its ACE inhibitory activity (IC50) reached 10.1 g/mL. The peptide VTGRFAGHPAAQ revealed the highest ?-glucosidase inhibitory activity (IC50 = 365.4 g/mL). A novel nutraceutical effect for peptides from an egg yolk hydrolysate was shown. PMID:25408464

  19. Yeast communities associated with sugarcane in Campos, Rio de Janeiro, Brazil.

    PubMed

    de Azeredo, L A; Gomes, E A; Mendonça-Hagler, L C; Hagler, A N

    1998-09-01

    Yeast communities associated with sugarcane leaves, stems and rhizosphere during different phases of plant development were studied near Campos, in Rio de Janeiro, Brazil. Atmospheric temperature, soil granulometry and pH, and sugar cane juice degree Brix and pH were determined. Yeast communities associated with sugarcane were obtained after cellular extraction by shaking, blending and shaking plus sonication, and cultured on Yeast Nitrogen Base Agar plus glucose (0.5%) and Yeast Extract-Malt Extract Agar. No significant differences in yeast counts were found among the cellular extraction treatments and culture media. 230 yeast cultures were identified according to standard methods, and distinct yeast communities were found for each substrate studied. The prevalent species isolated from sugarcane were Cryptococcus laurentii, Cryptococcus albidus, Rhodotorula mucilaginosa and Debaryomyces hansenii. PMID:10943361

  20. Hydrolysable tannin fed to entire male pigs affects intestinal production, tissue deposition and hepatic clearance of skatole.

    PubMed

    Čandek-Potokar, M; Škrlep, M; Batorek Lukač, N; Zamaratskaia, G; Prevolnik Povše, M; Velikonja Bolta, Š; Kubale, V; Bee, G

    2015-05-01

    The effect of adding hydrolysable tannins to the diet of fattening boars was studied. Performance, reproductive organ weights, salivary gland morphology, boar taint compounds and skatole metabolism were evaluated. At 123 days of age and 52 ± 6 kg liveweight, 24 Landrace × Large White boars were assigned within a litter to four treatment groups: control (T0 fed mixture with 13.2 MJ/kg, 17.5% crude proteins) and three experimental diets for which the T0 diet was supplemented with 1%, 2% and 3% of hydrolysable tannin-rich extract (T1, T2 and T3, respectively). Pigs were kept individually with ad libitum access to feed and water and slaughtered at 193 days of age and 122 ± 10 kg liveweight. Adding hydrolysable tannins to the diet had no negative effect on growth performance at 1% and 2%, whereas the 3% inclusion reduced feed intake and resulted in an adaptive response of the salivary glands (particularly parotid gland hypertrophy). Relative to T0, fat tissue skatole concentration was increased in the T1 group, but was similar in T2 and T3. Across treatments tissue skatole concentrations were proportional to the activity of hepatic CYP450. The results indicate the potential of tannin supplementation to reduce boar taint although further investigations are needed in order to establishing optimal dosage. PMID:25890671

  1. Angiotensin-converting enzyme-inhibitory activity in protein hydrolysates from normal and anthracnose disease-damaged Phaseolus vulgaris seeds.

    TOXLINE Toxicology Bibliographic Information

    Hernández-Álvarez AJ; Carrasco-Castilla J; Dávila-Ortiz G; Alaiz M; Girón-Calle J; Vioque-Peña J; Jacinto-Hernández C; Jiménez-Martínez C

    2013-03-15

    BACKGROUND: Bean seeds are an inexpensive source of protein. Anthracnose disease caused by the fungus Colletotrichum lindemuthianum results in serious losses in common bean (Phaseolus vulgaris L.) crops worldwide, affecting any above-ground plant part, and protein dysfunction, inducing the synthesis of proteins that allow plants to improve their stress tolerance. The aim of this study was to evaluate the use of beans damaged by anthracnose disease as a source of peptides with angiotensin-converting enzyme (ACE-I)-inhibitory activity.RESULTS: Protein concentrates from beans spoiled by anthracnose disease and from regular beans as controls were prepared by alkaline extraction and precipitation at isolelectric pH and hydrolysed using Alcalase 2.4 L. The hydrolysates from spoiled beans had ACE-I-inhibitory activity (IC(50) 0.0191 mg protein mL(-1)) and were very similar to those from control beans in terms of ACE-I inhibition, peptide electrophoretic profile and kinetics of hydrolysis. Thus preparation of hydrolysates using beans affected by anthracnose disease would allow for revalorisation of this otherwise wasted product.CONCLUSION: The present results suggest the use of spoiled bean seeds, e.g. anthracnose-damaged beans, as an alternative for the isolation of ACE-I-inhibitory peptides to be further introduced as active ingredients in functional foods.

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Pretreatment of lignocellulose biomass for biofuels production generates inhibitory compounds that interfere with microbial growth and subsequent fermentation. Remediation of the inhibitors by current physical, chemical, and biological abatement means is economically impractical and overcoming the i...

  3. Development of Silane Hydrolysate Binder for Thermal-Control Coatings

    NASA Technical Reports Server (NTRS)

    Patterson, W. J.

    1983-01-01

    Technical report describes theoretical and experimental development of methyltriethoxysilane (MTES) hydrolysate binder for white, titanium dioxidepigmented thermal-control coatings often needed on satellites. New coating is tougher and more abrasion-resistant than conventional coating, S-13G, which comprises zinc oxide in hydroxyl-therminated dimethylsiloxane binder.

  4. BUTANOL PRODUCTION FROM WHEAT STRAW HYDROLYSATE USING CLOSTRIDIUM BEIJERINCKII

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In these studies, butanol (acetone butanol ethanol or ABE) was produced from wheat straw hydrolysate (WSH) in batch cultures using Clostridium beijerinckii P260. In control fermentation, 48.9 gL**-1 glucose was used to produce 20.1 gL**-1 ABE with a productivity and yield of 0.28 gL**-1h**-1 and 0....

  5. Rheological and Functional Properties of Catfish Skin Protein Hydrolysates

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Catfish skin is an abundant and underutilized resource that can be used as a unique protein source to make fish skin hydrolysates. The objectives of this study were to: isolating soluble and insoluble proteins from hydrolyzed catfish skin and study the chemical and functional properties of the prote...

  6. [Effect of mutilus hydrolysate in Aleutian disease of minks].

    PubMed

    Uzenbaeva, L B; Iliukha, V A; Tiutiunnik, N N; Meldo, Kh I; Unzhakov, A R

    1999-01-01

    Addition of mutilus hydrolysate MIGI-K to rations of minks with virus plasmacytosis involving grave immunological disorders led to changes in the ratio of serum protein fractions and in the differential blood count. Normalization of the protein spectrum of minks with Aleutian disease apparently inhibits the development of disorders caused by hypergammaglobullnemia. PMID:10190240

  7. ISOLATION OF MICROORGANISMS FOR BIOLOGICAL DETOXIFICATION OF LIGNOCELLULOSIC HYDROLYSATES

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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 (5 mM), 5-hydrox...

  8. Rendered-protein hydrolysates for microbial synthesis of cyanophycin biopolymer

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Cyanophycin is a poly(arginyl-aspartate) biopolymer produced and stored intracellularly by bacteria. Cyanophycin has been proposed as a renewable replacement for petrochemical-based industrial products. An abundant source of amino acids and nitrogen such as in the form of protein hydrolysates is n...

  9. Interference of humic acids and DNA extracted directly from soil in detection and transformation of recombinant DNA from bacteria and a yeast.

    PubMed

    Tebbe, C C; Vahjen, W

    1993-08-01

    A two-step protocol for the extraction and purification of total DNA from soil samples was developed. Crude DNA extracts (100 microliters from 5 g of soil) were contaminated with humic acids at concentrations of 0.7 to 3.3 micrograms/microliters, depending on the type of soil extracted. The coextracted humic acid fraction of a clay silt was similar to a commercially available standard humic acid mixture, as determined by electrophoretic mobility in agarose gels, UV fluorescence, and inhibition assays with DNA-transforming enzymes. Restriction endonucleases were inhibited at humic acid concentrations of 0.5 to 17.2 micrograms/ml for the commercial product and 0.8 to 51.7 micrograms/ml for the coextracted humic acids. DNase I was less susceptible (MIC of standard humic acids, 912 micrograms/ml), and RNase could not be inhibited at all (MIC, > 7.6 mg/ml). High inhibitory susceptibilities for humic acids were observed with Taq polymerase. For three Taq polymerases from different commercial sources, MICs were 0.08 to 0.64 micrograms of the standard humic acids per ml and 0.24 to 0.48 micrograms of the coextracted humic acids per ml. The addition of T4 gene 32 protein increased the MIC for one Taq polymerase to 5.12 micrograms/ml. Humic acids decreased nonradioactive detection in DNA-DNA slot blot hybridizations at amounts of 0.1 micrograms and inhibited transformation of competent Escherichia coli HB101 with a broad-host-range plasmid, pUN1, at concentrations of 100 micrograms/ml. Purification of crude DNA with ion-exchange chromatography resulted in removal of 97% of the initially coextracted humic acids.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:7690221

  10. Alcohol production from Jerusalem artichoke using yeasts with inulinase activity

    SciTech Connect

    Guiraud, J.P.; Daurelles, J.; Galzy, P.

    1981-07-01

    The purpose of this article is to show that yeasts with inulinase activity can be used to produce ethanol from the Jerusalem artichoke (Helianthus tuberosus L.). The results show that a fermentable extract can be easily obtained from the Jerusalem artichoke even under cold conditions. Yeasts with inulinase activity can be used to produce ethanol with good profitability. 19 refs.

  11. Sweetpotato vines hydrolysate promotes single cell oils production of Trichosporon fermentans in high-density molasses fermentation.

    PubMed

    Shen, Qi; Lin, Hui; Wang, Qun; Fan, Xiaoping; Yang, Yuyi; Zhao, Yuhua

    2015-01-01

    This study investigated the co-fermentation of molasses and sweetpotato vine hydrolysate (SVH) by Trichosporon fermentans. T. fermentans showed low lipid accumulation on pure molasses; however, its lipid content increased by 35% when 10% SVH was added. The strong influence of SVH on lipid production was further demonstrated by the result of sensitivity analysis on effects of factors based on an artificial neural network model because the relative importance value of SVH dosage for lipid production was only lower than that of fermentation time. Scanning electron microscope observation and flow cytometry of yeast cells grown in culture with and without SVH showed that less deformation cells were involved in the culture with SVH. The activity of malic enzyme, which plays a key role in fatty acid synthesis, increased from 2.4U/mg to 3.7U/mg after SVH added. All results indicated SVH is a good supplement for lipid fermentation on molasses. PMID:25461010

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

    PubMed Central

    2012-01-01

    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

  13. Enzyme Hydrolysates from Stichopus horrens as a New Source for Angiotensin-Converting Enzyme Inhibitory Peptides

    PubMed Central

    Forghani, Bita; Ebrahimpour, Afshin; Bakar, Jamilah; Abdul Hamid, Azizah; Hassan, Zaiton; Saari, Nazamid

    2012-01-01

    Stichopus horrens flesh was explored as a potential source for generating peptides with angiotensin-converting enzyme (ACE) inhibitory capacity using 6 proteases, namely alcalase, flavourzyme, trypsin, papain, bromelain, and protamex. Degree of hydrolysis (DH) and peptide profiling (SDS-PAGE) of Stichopus horrens hydrolysates (SHHs) was also assessed. Alcalase hydrolysate showed the highest DH value (39.8%) followed by flavourzyme hydrolysate (32.7%). Overall, alcalase hydrolysate exhibited the highest ACE inhibitory activity (IC50 value of 0.41 mg/mL) followed by flavourzyme hydrolysate (IC50 value of 2.24 mg/mL), trypsin hydrolysate (IC50 value of 2.28 mg/mL), papain hydrolysate (IC50 value of 2.48 mg/mL), bromelain hydrolysate (IC50 value of 4.21 mg/mL), and protamex hydrolysate (IC50 value of 6.38 mg/mL). The SDS-PAGE results showed that alcalase hydrolysate represented a unique pattern compared to others, which yielded potent ACE inhibitory peptides with molecular weight distribution lower than 20 kDa. The evaluation of the relationship between DH and IC50 values of alcalase and flavourzyme hydrolysates revealed that the trend between those parameters was related to the type of the protease used. We concluded that the tested SHHs would be used as a potential source of functional ACE inhibitory peptides for physiological benefits. PMID:22927875

  14. Evaluation of Mucor indicus and Saccharomyces cerevisiae capability to ferment hydrolysates of rape straw and Miscanthus giganteus as affected by the pretreatment method.

    PubMed

    Lewandowska, Małgorzata; Szymańska, Karolina; Kordala, Natalia; Dąbrowska, Aneta; Bednarski, Włodzimierz; Juszczuk, Andrzej

    2016-07-01

    Rape straw and Miscanthus giganteus was pretreated chemically with oxalic acid or sodium hydroxide. The pretreated substrates were hydrolyzed with enzymatic preparations of cellulase, xylanase and cellobiase. The highest concentration of reducing sugars was achieved after hydrolysis of M. giganteus pretreated with NaOH (51.53gdm(-3)). In turn, the highest yield of enzymatic hydrolysis determined based on polysaccharides content in the pretreated substrates was obtained in the experiments with M. giganteus and oxalic acid (99.3%). Rape straw and M. giganteus hydrolysates were fermented using yeast Saccharomyces cerevisiae 7, NRRL 978 or filamentous fungus Mucor rouxii (Mucor indicus) DSM 1191. The highest ethanol concentration was determined after fermentation of M. giganteus hydrolysate pretreated with NaOH using S. cerevisiae (1.92% v/v). Considering cellulose content in the pretreated solid, the highest degree of its conversion to ethanol (86.2%) was achieved after fermentation of the hydrolysate of acid-treated M. giganteus using S. cerevisiae. PMID:27107482

  15. Comparison of digestibility and quality of intact proteins with their respective hydrolysates.

    PubMed

    Potier, Mylène; Tomé, Daniel

    2008-01-01

    Quality of proteins depends on their composition in essential amino acids and on the availability of amino acids. Great interest has been shown in the role played by hydrolysates of proteins in clinical diets for pathologies with reduced absorptive capacity and food allergies caused by intact protein epitopes. Milk proteins are the most important protein source used in the development of protein hydrolysates designed for nutritional support of patients. Several studies have shown that casein and whey hydrolysates have a composition in amino acids equivalent to that in native milk proteins and that digestibility is similar or better. Among plant proteins, soy is the major source of hydrolysates. Soy hydrolysates are also used in infant formulas. Plant hydrolysates have good functional properties and a nutritional quality similar to that of starting material. Some technical improvements in production of hydrolysates, particularly for plants, are nevertheless necessary to improve product palatability. PMID:18727562

  16. Antioxidant and cryoprotective effects of Amur sturgeon skin gelatin hydrolysate in unwashed fish mince.

    PubMed

    Nikoo, Mehdi; Benjakul, Soottawat; Xu, Xueming

    2015-08-15

    Antioxidant and cryoprotective effects of Amur sturgeon skin gelatin hydrolysates prepared using different commercial proteases in unwashed fish mince were investigated. Gelatin hydrolysates prepared using either Alcalase or Flavourzyme, were effective in preventing lipid oxidation as evidenced by the lower thiobarbituric acid-reactive substances formation. Gelatin hydrolysates were able to retard protein oxidation as indicated by the retarded protein carbonyl formation and lower loss in sulfhydryl content. In the presence of gelatin hydrolysates, unwashed mince had higher transition temperature of myosin and higher enthalpy of myosin and actin as determined by differential scanning calorimetry. Based on low field proton nuclear magnetic resonance analysis, gelatin hydrolysates prevented the displacement of water molecules between the different compartments, thus stabilizing the water associated with myofibrils in unwashed mince induced by repeated freeze-thawing. Oligopeptides in gelatin hydrolysates more likely contributed to the cryoprotective effect. Thus, gelatin hydrolysate could act as both antioxidant and cryoprotectant in unwashed fish mince. PMID:25794753

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

    NASA Astrophysics Data System (ADS)

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

    2010-03-01

    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 μg 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.

  18. Conditioning of dilute-acid pretreated corn stover hydrolysate liquors by treatment with lime or ammonium hydroxide to improve conversion of sugars to ethanol.

    PubMed

    Jennings, Edward W; Schell, Daniel J

    2011-01-01

    Dilute-acid pretreatment of lignocellulosic biomass enhances the ability of enzymes to hydrolyze cellulose to glucose, but produces many toxic compounds that inhibit fermentation of sugars to ethanol. The objective of this study was to compare the effectiveness of treating hydrolysate liquor with Ca(OH)2 and NH4OH for improving ethanol yields. Corn stover was pretreated in a pilot-scale reactor and then the liquor fraction (hydrolysate) was extracted and treated with various amounts of Ca(OH)2 or NH4OH at several temperatures. Glucose and xylose in the treated liquor were fermented to ethanol using a glucose-xylose fermenting bacteria, Zymomonas mobilis 8b. Sugar losses up to 10% occurred during treatment with Ca(OH)2, but these losses were two to fourfold lower with NH4OH treatment. Ethanol yields for NH4OH-treated hydrolysate were 33% greater than those achieved in Ca(OH)2-treated hydrolysate and pH adjustment to either 6.0 or 8.5 with NH4OH prior to fermentation produced equivalent ethanol yields. PMID:20801647

  19. Media for preservative resistant yeasts: a collaborative study.

    PubMed

    Hocking, A D

    1996-04-01

    An international collaborative study was carried out to determine the most effective medium for selective isolation and enumeration of preservative resistant yeasts. Such a medium should prevent the growth of other yeasts such as Saccharomyces cerevisiae that are tolerant to lower levels of commonly used food preservatives, and sensitive yeasts such as Rhodotorula species. The study compared two non-selective media that are in common use for cultivation of yeasts from foods, Malt Extract agar (MEA) and Tryptone Glucose Yeast extract agar (TGY) with media made selective for preservative resistant yeasts by addition of 0.5% acetic acid to these two basal media (MEAA and TGYA). A fifth medium, Zygosaccharomyces bailii medium (ZBM) was also included in the study. These media were compared for their efficacy in selective isolation and enumeration of the preservative resistant yeasts Zygosaccharomyces bailii, Schizosaccharomyces pombe and Pichia membranaefaciens. MEA and TGY without acetic acid were used as control, non-selective media, and Rhodotorula glutinis was the preservative sensitive control culture. Seven laboratories in six countries took part in the study. Of the non-selective media, TGY generally gave the highest counts, and TGY amended with 0.5% acetic acid (TGYA) was the best medium for recovery of all three preservative-resistant yeasts. ZBM was found to be selective for Z. bailii, but counts of this yeast on ZBM were significantly lower than on TGYA. R. glutinis did not grow on any of the selective media. PMID:8796419

  20. Efficient production of sophorolipids by Starmerella bombicola using a corncob hydrolysate medium.

    PubMed

    Konishi, Masaaki; Yoshida, Yuka; Horiuchi, Jun-ichi

    2015-03-01

    Sophorolipids (SLs) are amphiphilic compounds produced from a variety of saccharides and vegetable oils by the yeast Starmerella bombicola and related strains, and they have commercial uses as detergents. In the present study, SL production was investigated using a corncob hydrolysate (CCH) medium derived from lignocellulosic feedstocks as a source of hydrophilic carbon substrates. Excess sulfuric acid concentrations during pretreatment of the corncobs increased the furfural concentrations and turned the CCH dark brown. The optimal sulfuric acid concentration was 1% (w/v), and the treated CCH, containing 45 g/l glucose, allowed the production of 33.7 g/l of SLs following 4 days of cultivation. Additional autoclaving (121°C, 20 min) inhibited SL production and cell growth by 36% and 40%, respectively. Ammonium nitrate (0.1 g-N/l) restored SL production to the autoclaved CCH. Finally, a cost-effective SL production of 49.2 g/l, with a volumetric productivity of 12.3 g/l/day, was achieved using CCH medium during batch cultivation in a jar fermentor. PMID:25240400

  1. Further Improvement of the Robust Recombinant Saccharomyces Yeast for the Conversion of Lignocellulosic Biomass to Ethanol

    SciTech Connect

    Ho, Nancy, W. Y.; Adamec, Jiri; Mosier, Nathan, S.; Sedlak, Miroslav

    2011-04-07

    Since 1980, the PI’s laboratory at Purdue University has been at the forefront in developing recombinant Saccharomyces yeast for cellulosic ethanol production. Their innovation enabled them to successfully develop the recombinant Saccharomyces yeast strain 424A(LNH-ST) that has been validated by scientists in industry, universities, and National Laboratories. Strain 424A(LNH-ST) has also been used by a company to produce cellulosic ethanol since 2004. Nevertheless, this strain still needs improvement, particularly to achieve high ethanol titer when cellulosic biomass hydrolysates are used for ethanol production. In this project, we were able to carry out a total genetic overhaul of our yeast by carrying out nine different tasks to improve our 424A(LNH-ST) strain. Through these tasks we enabled the yeast to co-ferment arabinose together with other four sugars generally present in all cellulosic biomass. Thus 424A(LNH-ST) can now ferment all five sugars, glucose, xylose, mannose, galactose and arabinose present in any cellulosic biomass. We also successfully used adaptation techniques and direct genetic improvements to develop improved 424A(LNH-ST) strains that are more resistant to acetic acid or ethanol. These are the most significant inhibitors of those commonly present in cellulosic hydrolysates that prevent 424A(LNH-ST) from producing high concentrations of cellulosic ethanol. The acetic acid resistant strain has 89% better xylose utilization in the presence of acetic acid and 25% better overall ethanol yield. The ethanol resistant strain has 250% better ethanol volumetric productivity. The three tasks for improving the main metabolic pathways have all been successfully completed but the impact of these improvements was less dramatic. This demonstrates our yeast already has effective metabolic systems for co-fermenting cellulosic sugars. However, our attempt to improve the yeast to transport xylose and arabinose more efficiently had only limited success. Thus improving yeast sugar transport system continues to be a significant challenge.

  2. Further Improvement of the Robust Recombinant Saccharomyces Yeast for the Conversion of Lignocellulosic Biomass to Ethanol

    SciTech Connect

    Ho, Nancy W. Y.; Adamec, Jiri; Mosier, Nathan, S.; Sedlak, Miroslav

    2011-04-09

    Since 1980, the PI’s laboratory at Purdue University has been at the forefront in developing recombinant Saccharomyces yeast for cellulosic ethanol production. Their innovation enabled them to successfully develop the recombinant Saccharomyces yeast strain 424A(LNH-ST) that has been validated by scientists in industry, universities, and National Laboratories. Strain 424A(LNH-ST) has also been used by a company to produce cellulosic ethanol since 2004. Nevertheless, this strain still needs improvement, particularly to achieve high ethanol titer when cellulosic biomass hydrolysates are used for ethanol production. In this project, we were able to carry out a total genetic overhaul of our yeast by carrying out nine different tasks to improve our 424A(LNH-ST) strain. Through these tasks we enabled the yeast to co-ferment arabinose together with other four sugars generally present in all cellulosic biomass. Thus 424A(LNH-ST) can now ferment all five sugars, glucose, xylose, mannose, galactose and arabinose present in any cellulosic biomass. We also successfully used adaptation techniques and direct genetic improvements to develop improved 424A(LNH-ST) strains that are more resistant to acetic acid or ethanol. These are the most significant inhibitors of those commonly present in cellulosic hydrolysates that prevent 424A(LNH-ST) from producing high concentrations of cellulosic ethanol. The acetic acid resistant strain has 89% better xylose utilization in the presence of acetic acid and 25% better overall ethanol yield. The ethanol resistant strain has 250% better ethanol volumetric productivity. The three tasks for improving the main metabolic pathways have all been successfully completed but the impact of these improvements was less dramatic. This demonstrates our yeast already has effective metabolic systems for co-fermenting cellulosic sugars. However, our attempt to improve the yeast to transport xylose and arabinose more efficiently had only limited success. Thus improving yeast sugar transport system continues to be a significant challenge.

  3. Optimisation of methodology for enumeration of xerophilic yeasts from foods.

    PubMed

    Andrews, S; de Graaf, H; Stamation, H

    1997-04-01

    Xerophilic yeasts grow in intermediate moisture foods (aw, 0.65-0.85) such as sugar syrups, fruit concentrates, jams and brines. Non-osmophilic yeasts are enumerated by diluting in 0.1% peptone and then plated onto media such as malt extract or glucose yeast extract agar. In the presence of moulds the yeasts are enumerated in dichloran rose bengal chloramphenicol agar (DRBC). These procedures were demonstrated to be unsatisfactory for the enumeration of xerophilic yeasts in low aw foods. Investigations using pure cultures of xerophilic yeasts as well as naturally contaminated apple juice concentrates and glacé cherries have shown that a reduced aw diluent, in particular 30% w/w glycerol in combination with tryptone 10% glucose yeast extract agar (TGY) optimises the recovery of the yeasts, especially sublethally injured cells. The inclusion of sodium chloride in either the diluents or the culture media was not necessary to optimise the recovery of D. hansenii growing in 20% sodium chloride broths. PMID:9105918

  4. Yeast improves resistance to environmental challenges

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Alphamune™, a yeast extract antibiotic alternative, was added at either 1 lb/ton or 2 lb/ton to a turkey starter diet. Two trials were conducted to evaluate the effects of Alphamune™ on gut maturation of 7 and 21 day old poults. Sections from the mid-point of the duodenum, jejunum and ileum of each ...

  5. Secretagogues and Growth Factors in Fish and Crustacean Protein Hydrolysates.

    PubMed

    Cancre; Ravallec; Van Wormhoudt A; Stenberg; Gildberg; Le Gal Y

    1999-09-01

    : The search for new molecules in fish protein hydrolysates is of great interest in animal feeding as it is in aquaculture, fertilizer, cosmetic, and pharmacologic domains. Different sources of hydrolysates such as shrimp waste (Pandalus borealis), cod (Gadus morhua) head, and head and viscera of sardine (Sardina pilchardus), obtained after hydrolysis or autolysis, were tested on fibroblast cell cultures and by gastrin radioimmunoassay. The level of hydrolysis seems to play an important role in the presence of biological peptides. Elution profile on a gel filtration Sephadex G-50 column was used to estimate the degree of hydrolysis of the fractions studied. Growth-factor-like activities were found in less-hydrolyzed fractions. Conversely, the most-hydrolyzed fractions showed gastrin and cholecystokinin immunoreactivity. PMID:10525683

  6. Use of Protein Hydrolysates in Industrial Starter Culture Fermentations

    NASA Astrophysics Data System (ADS)

    Ummadi, Madhavi (Soni); Curic-Bawden, Mirjana

    Lactic acid bacteria (LAB) have been used as starter cultures for fermenting foods long before the importance of microorganisms were recognized. The most important group of LAB are the lactococci, lactobacilli, streptococci, and pediococci. Additionally, bifidobacteria have been included as a probiotic, providing added value to the product. Since the genera involved are so diverse, the nutritional requirements (energy, carbon and nitrogen sources) differ significantly between and within species. Designing an optimum fermentation medium for production of active and vigorous LAB starter cultures and probiotics requires selecting the right raw ingredients, especially protein hydrolysates that can provide adequate nutrients for growth and viability. This chapter attempts to describe the application of various commercial protein hydrolysates used for production of dairy and meat starter cultures, with special emphasis on meeting the nitrogen requirements of industrially important LAB species.

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

    PubMed Central

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

    2012-01-01

    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

  8. In vitro antithrombotic activities of peanut protein hydrolysates.

    PubMed

    Zhang, Shao Bing

    2016-07-01

    The antithrombotic activities of peanut protein hydrolysates were investigated using a microplates assay. When peanut proteins were hydrolyzed to a limited extent by various enzymes, their thrombin inhibitory abilities were significantly enhanced. However, the resultant hydrolysates showed significantly different activities even at the same degrees of hydrolysis. The hydrolysates generated by Alcalase 2.4L displayed the best antithrombotic activities and the hydrolysis process was further optimized by response surface methodology. The antithrombotic activities were increased to 86% based on a protein concentration of 50mg/ml under the optimal conditions: pH 8.5, enzyme concentration of 5000IU/g of peanut proteins, and 2h hydrolysis time at 50°C. The Alcalase 2.4L crude hydrolysates were then fractionated successively by preparative and semi-preparative reverse-phase high-performance liquid chromatography (RP-HPLC). The peptide fraction collected inhibited thrombin-catalyzed coagulation of fibrinogen completely at a concentration of 0.4mg/ml, with an antithrombotic activity close to that of heparin at quite a low concentration (0.2mg/ml). This peptide fraction was further analyzed by online reverse-phase ultra-performance liquid chromatography (RP-UPLC) coupled to matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS), and three new peptides were identified as Ser-Trp-Ala-Gln-Leu, Gly-Asn-His-Glu-Ala-Gly-Glu and Cys-Phe-Asn-Glu-Tyr-Glu, respectively. This research provided an effective way to produce antithrombotic peptides from peanut proteins, and also helped to elucidate the structure-function relationships of peanut peptides. PMID:26920259

  9. Kinetic studies of cellodextrins hydrolyses by exocellulase from trichoderma reesei

    SciTech Connect

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

    1980-11-01

    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.

  10. Pexophagy in yeasts.

    PubMed

    Oku, Masahide; Sakai, Yasuyoshi

    2016-05-01

    Pexophagy, selective degradation of peroxisomes via autophagy, is the main system for reducing organelle abundance. Elucidation of the molecular machinery of pexophagy has been pioneered in studies of the budding yeast Saccharomyces cerevisiae and the methylotrophic yeasts Pichia pastoris and Hansenula polymorpha. Recent analyses using these yeasts have elucidated the molecular machineries of pexophagy, especially in terms of the interactions and modifications of the so-called adaptor proteins required for guiding autophagic membrane biogenesis on the organelle surface. Based on the recent findings, functional relevance of pexophagy and another autophagic pathway, mitophagy (selective autophagy of mitochondria), is discussed. We also discuss the physiological importance of pexophagy in these yeast systems. PMID:26409485

  11. The Use of Protein Hydrolysates for Weed Control

    NASA Astrophysics Data System (ADS)

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

    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.

  12. Rendered-protein hydrolysates for microbial synthesis of cyanophycin biopolymer.

    PubMed

    Solaiman, Daniel K Y; Garcia, Rafael A; Ashby, Richard D; Piazza, George J; Steinbüchel, Alexander

    2011-10-01

    Cyanophycin is a poly(arginyl-aspartate) biopolymer produced and stored intracellularly by bacteria. Cyanophycin has been proposed as a renewable replacement for petrochemical-based industrial products. An abundant source of amino acids and nitrogen such as in the form of protein hydrolysates is needed for the biosynthesis of cyanophycin. Rendered proteins are largely used as a feed supplement in animal husbandry and aquaculture. New uses would expand the market size of this class of protein coproducts. We prepared and thoroughly characterized the hydrolysates of meat and bone meal, and proceeded to demonstrate for the first time that these hydrolysates could be used in the fermentative production of cyanophycin. Using the enzyme-hydrolyzed meat and bone meal preparation, we obtained crude cyanophycin product at 33-35% level of that produced using the reference casamino acids in both shake-flask and 10-L bioreactor fermentation studies. Polyacrylamide-gel electrophoresis of the cyanophycin under denaturing conditions showed the molecular weight of the isolated polyamide at 24kDa. Our results open a new avenue for the utilization of rendered protein coproducts to produce the cyanophycin biopolymer. PMID:21501699

  13. Antioxidant activity of whey protein hydrolysates in milk beverage system.

    PubMed

    Mann, Bimlesh; Kumari, Anuradha; Kumar, Rajesh; Sharma, Rajan; Prajapati, Kishore; Mahboob, Shaik; Athira, S

    2015-06-01

    The aim of the present study was to evaluate the antioxidant activity of flavoured milk enriched with antioxidative whey protein hydrolysates (WPHs) by radical scavenging method. Whey protein concentrate (WPC) was hydrolyzed by using three commercial proteases; flavouzyme, alcalase and corolase PP and these WPHs were analyzed for degree of hydrolysis and antioxidant activity. The antioxidant activities of these WPHs were evaluated using ABTS method. Trolox equivalent antioxidant activity of all the hydrolysates i.e. flavourzyme (0.81 ± 0.04), alcalase (1.16 ± 0.05) and corolase (1.42 ± 0.12) was higher than the WPC (0.19 ± 0.01). Among these, whey protein hydrolysates prepared using corolase showed maximum antioxidant activity. Total 15 β-lactoglobulin, 1 α-lactoalbumin, and 6 β-casein derived peptide fragments were identified in the WPHs by LC-MS/MS. Due to their size and characteristic amino acid composition, all the identified peptides may contribute for the antioxidant activity. The strawberry and chocolate flavoured milk was supplemented with WPC and WPHs and 2 % addition has shown increase in antioxidant activity upto 42 %. The result suggests that WPH could be used as natural biofunctional ingredients in enhancing antioxidant properties of food products. PMID:26028704

  14. Antioxidant properties of Australian canola meal protein hydrolysates.

    PubMed

    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

    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 10.1μg/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

  15. Safety evaluation of fish protein hydrolysate supplementation in malnourished children.

    PubMed

    Nesse, Knut Olav; Nagalakshmi, A P; Marimuthu, P; Singh, Mamta; Bhetariya, Preetida J; Ho, Manki; Simon, Ryan R

    2014-06-01

    Amizate® is a proprietary protein hydrolysate preparation derived from Atlantic salmon (Salmo salar) using endogenous hydrolytic enzymes; it contains mostly free amino acids and short peptides, as well as small amounts of micronutrients (i.e., vitamins and minerals). In this study, the safety of supplementation with fish protein hydrolysate (Amizate®) was examined in 438 malnourished children in a randomized, placebo-controlled, double-blind, and parallel study. The children were between the ages of six to eight and met the Gomez classification for mild or moderate malnutrition. They were randomized to receive one of three interventions for four months, including a chocolate drink (control), or Amizate® (3 or 6g/day) in a chocolate drink. Administration of Amizate® was well-tolerated, with no adverse events reported. Growth (i.e., body weight gain, changes in height, and body mass index) was not negatively impacted by administration of Amizate®, and routine biochemical analysis of blood and urine samples did not reveal any abnormalities that were attributable to the intervention. Findings from this study demonstrate that daily consumption of 3 or 6g of fish protein hydrolysate (Amizate®) was safe and suitable for supplementing the diets of malnourished children. PMID:24569051

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

    PubMed

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

    2006-11-01

    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

  17. Electrochemical detoxification of phenolic compounds in lignocellulosic hydrolysate for Clostridium fermentation.

    PubMed

    Lee, Kyung Min; Min, Kyoungseon; Choi, Okkyoung; Kim, Ki-Yeon; Woo, Han Min; Kim, Yunje; Han, Sung Ok; Um, Youngsoon

    2015-01-01

    Lignocellulosic biomass is being preferred as a feedstock in the biorefinery, but lignocellulosic hydrolysate usually contains inhibitors against microbial fermentation. Among these inhibitors, phenolics are highly toxic to butyric acid-producing and butanol-producing Clostridium even at a low concentration. Herein, we developed an electrochemical polymerization method to detoxify phenolic compounds in lignocellulosic hydrolysate for efficient Clostridium fermentation. After the electrochemical detoxification for 10h, 78%, 77%, 82%, and 94% of p-coumaric acid, ferulic acid, vanillin, and syringaldehyde were removed, respectively. Furthermore, 71% of total phenolics in rice straw hydrolysate were removed without any sugar-loss. Whereas the cell growth and metabolite production of Clostridium tyrobutyricum and Clostridium beijerinckii were completely inhibited in un-detoxified hydrolysate, those in detoxifying rice straw hydrolysate were recovered to 70-100% of the control cultures. The electrochemical detoxification method described herein provides an efficient strategy for producing butanol and butyric acid through Clostridium fermentation with lignocellulosic hydrolysate. PMID:25863199

  18. Mild protein hydrolysation of lactose-free milk further reduces milk-related gastrointestinal symptoms.

    PubMed

    Turpeinen, Anu; Kautiainen, Hanna; Tikkanen, Marja-Leena; Sibakov, Timo; Tossavainen, Olli; Myllyluoma, Eveliina

    2016-05-01

    Gastrointestinal symptoms associated with milk are common. Besides lactose, milk proteins may cause symptoms in sensitive individuals. We have developed a method for mild enzymatic hydrolysation of milk proteins and studied the effects of hydrolysed milk on gastrointestinal symptoms in adults with a self-diagnosed sensitive stomach. In a double blind, randomised placebo-controlled study, 97 subjects consumed protein-hydrolysed lactose-free milk or commercially available lactose-free milk for 10 d. Frequency of gastrointestinal symptoms during the study period was reported and a symptom score was calculated. Rumbling and flatulence decreased significantly in the hydrolysed milk group (P < 0·05). Also, the total symptom score was lower in subjects who consumed hydrolysed milk (P < 0·05). No difference between groups was seen in abdominal pain (P = 0·47) or bloating (P = 0·076). The results suggest that mild enzymatic protein hydrolysation may decrease gastrointestinal symptoms in adults with a sensitive stomach. PMID:27034058

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

    PubMed

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

    2014-06-01

    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

  20. [Hygienic characteristics of food hydrolysates made from small ocean fish and krill].

    PubMed

    Solomko, G I; Prudnikova, L V; Prokopenko, O V; Orlova, T A

    1985-01-01

    A study was made of the biological value of acid and enzymatic hydrolysates from capelin, luminous anchovy and krill. Hydrolysates were obtained with the use of protosubtilin G-10-X or hydrochloric acid. The products were found to contain 39 to 64% of "crude" protein, with about 40% of total nitrogen belonging to non-protein one, 0.47-2.07% of lipids, 29.7-54.3% of mineral substances including 26.6-52.4% of sodium chloride. All the hydrolysates were limited in tryptophan, the deficiency being more demonstrable in acid hydrolysates. Enzymatic hydrolysate from luminous anchovy was rich in sulfur-containing amino acids (score 112%), whereas the remaining products were marked by their deficiency (score 53-90%). The products were rich in lysine, leucine, isoleucine, and aromatic amino acids. The anabolic efficacy was discovered to be the highest for enzymatic hydrolysate from luminous anchovy, exceeding the analogous characteristics for casein. The biological value of hydrolysate from capelin and krill was lower than that of casein. This was supported by the amino acid analysis data. The assimilability of all hydrolysates was established as fairly high. Hydrolysates are employed for manufacturing broth bricks and pastes. PMID:4082514

  1. Effect of Yeast Hulls on Stuck and Sluggish Wine Fermentations: Importance of the Lipid Component

    PubMed Central

    Munoz, Eeva; Ingledew, W. M.

    1989-01-01

    The effect of yeast hulls (yeast ghosts) on sluggish or stuck white wine fermentations was studied. The enhancing effect on yeast growth and fermentation rate displayed by the hulls was shown to be similar to the effect provided by lipid extract from the same hulls. Unsaturated fatty acids and sterols were incorporated into the yeast from lipid extracts during fermentation carried out under oxygen-limited conditions. Adsorption of toxic medium-chain fatty acid (decanoic acid) onto the yeast hulls took place through a dialysis membrane. However, when the hulls were placed inside a dialysis bag, the increase in yeast growth and fermentation rate seen when freely suspended hulls were used did not occur. Accordingly, the effect of yeast hulls in preventing stuck fermentations cannot be attributed only to the adsorption and consequent removal of medium-chain fatty acids from the juice. PMID:16347950

  2. 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

    2014-01-01

    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

  3. Quantifying pretreatment degradation compounds in solution and accumulated by cells during solids and yeast recycling in the Rapid Bioconversion with Integrated recycling Technology process using AFEX™ corn stover.

    PubMed

    Sarks, Cory; Higbee, Alan; Piotrowski, Jeff; Xue, Saisi; Coon, Joshua J; Sato, Trey K; Jin, Mingjie; Balan, Venkatesh; Dale, Bruce E

    2016-04-01

    Effects of degradation products (low molecular weight compounds produced during pretreatment) on the microbes used in the RaBIT (Rapid Bioconversion with Integrated recycling Technology) process that reduces enzyme usage up to 40% by efficient enzyme recycling were studied. Chemical genomic profiling was performed, showing no yeast response differences in hydrolysates produced during RaBIT enzymatic hydrolysis. Concentrations of degradation products in solution were quantified after different enzymatic hydrolysis cycles and fermentation cycles. Intracellular degradation product concentrations were also measured following fermentation. Degradation product concentrations in hydrolysate did not change between RaBIT enzymatic hydrolysis cycles; the cell population retained its ability to oxidize/reduce (detoxify) aldehydes over five RaBIT fermentation cycles; and degradation products accumulated within or on the cells as RaBIT fermentation cycles increased. Synthetic hydrolysate was used to confirm that pretreatment degradation products are the sole cause of decreased xylose consumption during RaBIT fermentations. PMID:26802184

  4. alpha-Lactalbumin hydrolysate stimulates glucagon-like peptide-2 secretion and small intestinal growth in suckling rats.

    PubMed

    Izumi, Hirohisa; Ishizuka, Satoshi; Inafune, Ayako; Hira, Tohru; Ozawa, Kazuhiro; Shimizu, Takashi; Takase, Mitsunori; Hara, Hiroshi

    2009-07-01

    We investigated whether bovine milk constituents influenced glucagon-like peptide (GLP)-2 secretion and intestinal growth in suckling rats. Male Sprague-Dawley rats (14 d old) received i.g. infusions of a milk protein fraction, a lactose solution, or the cream fraction of milk. The serum concentration of GLP-2, but not GLP-1, markedly increased in rats administered milk protein compared with those given the lactose solution or the cream fraction from 60 to 120 min after administration. In another experiment, both casein (CN) and whey protein isolate stimulated GLP-2 secretion at 120 min after administration, but soy protein and ovalbumin did not. Stimulation of GLP-2 secretion by several milk proteins was similar, including alpha-CN, alpha-lactalbumin (alpha-La), and beta-lactoglobulin, in a separate experiment. A hydrolysate of alpha-La obtained by incubation with protease A extracted from Aspergillus oryzae (LaHPA) caused almost twice the GLP-2 release due to intact alpha-La and other alpha-La hydrolysates. Free amino acid concentrations and molecular size distributions did not differ among alpha-La hydrolysates, including LaHPA. In rat pups reared with milk formulae containing alpha-La or LaHPA, LaHPA significantly promoted small intestinal elongation and increased the number of crypt epithelial cells compared with a formula containing intact alpha-La. LaHPA administration also increased the maltase:lactase activity ratio, a marker of maturation of the intestinal mucosa. In conclusion, milk proteins stimulate GLP-2 secretion and contribute to growth and maturation of the small intestine in suckling rats. PMID:19494023

  5. Condensed and hydrolysable tannins as antioxidants influencing the health.

    PubMed

    Koleckar, Vit; Kubikova, Katerina; Rehakova, Zuzana; Kuca, Kamil; Jun, Daniel; Jahodar, Ludek; Opletal, Lubomir

    2008-05-01

    Natural polyphenols are a wide class of secondary plant metabolites and represent an abundant antioxidant component of human diet. An important, but often neglected group of natural polyphenols, are tannins. This review offers a general description of chemistry of both hydrolysable and condensed tannins (proanthocyanidins), the mechanisms of their antioxidation action, like free radical scavenging activity, chelation of transition metals, inhibition of prooxidative enzymes and lipid peroxidation. The mechanisms of action of antibacterial, antiviral, anticarcinogenic, cardiovascular system preventing, and antiinflammatory effects as well as the absorption, metabolic fate and positive in vivo effects of tannins are enclosed. PMID:18473933

  6. Improved alcohol production employing SSF with thermotolerant yeast

    SciTech Connect

    Tsao, G.T.; Cao, N.; Gong, C.S.

    1996-12-31

    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.

  7. Production of arabitol by yeasts: current status and future prospects.

    PubMed

    Kordowska-Wiater, M

    2015-08-01

    Arabitol belongs to the pentitol family and is used in the food industry as a sweetener and in the production of human therapeutics as an anticariogenic agent and an adipose tissue reducer. It can also be utilized as a substrate for chemical products such as arabinoic and xylonic acids, propylene, ethylene glycol, xylitol and others. It is included on the list of 12 building block C3-C6 compounds, designated for further biotechnological research. This polyol can be produced by yeasts in the processes of bioconversion or biotransformation of waste materials from agriculture, the forest industry (l-arabinose, glucose) and the biodiesel industry (glycerol). The present review discusses research on native yeasts from the genera Candida, Pichia, Debaryomyces and Zygosaccharomyces as well as genetically modified strains of Saccharomyces cerevisiae which are able to utilize biomass hydrolysates to effectively produce L- or D-arabitol. The metabolic pathways of these yeasts leading from sugars and glycerol to arabitol are presented. Although the number of reports concerning microbial production of arabitol is rather limited, the research on this topic has been growing for the last several years, with researchers looking for new micro-organisms, substrates and technologies. PMID:25809659

  8. Organic fraction of municipal solid waste as a suitable feedstock for the production of lipid by oleaginous yeast Cryptococcus aerius.

    PubMed

    Ghanavati, Hossein; Nahvi, Iraj; Karimi, Keikhosro

    2015-04-01

    The detoxified pre-hydrolysate and enzymatic hydrolysate of OFMSW were used as substrates for lipid production by Cryptococcus aerius. Factorial experimental designs were employed for the optimization of dilute acid pre-hydrolysis, detoxification by over-liming, enzymatic hydrolysis, and lipid production. OFMSW pre-hydrolysis with 3% H2SO4 for 45 min was found to be the optimal treatment, resulted in total sugar concentration of 65.5 g/L (32.8% yield, based on grams of total reducing sugar per gram of OFMSW). The optimal detoxification conditions of the pre-hydrolysate by over-liming was incubation at 30 °C and pH 11 for 24h, resulted in the reduction of total nitrogen, total phenolic compounds, and furans by 51.3%, 45.1%, and 100%, respectively. The residual solid was subjected to enzymatic hydrolysis, and the highest sugar concentration of 30.5 g/L was obtained. At optimal conditions, the yeast cultivation on the detoxified pre-hydrolysate and enzymatic hydrolysate resulted in the lipid production of 3.9 g/L (12.8% yield, based on g lipid per g consumed sugar) and 4.3g/L (17.1% yield, based on g lipid per g consumed sugar), respectively. The elemental analysis showed the presence of heavy metals including iron (925 mg/l), zinc (59 mg/l), lead (4.7 mg/l), and nickel (3.5mg/l) in the pre-hydrolysate, which were significantly reduced by the over-liming detoxification. PMID:25595390

  9. Enzymatic protein hydrolysates from high pressure-pretreated isolated pea proteins have better antioxidant properties than similar hydrolysates produced from heat pretreatment.

    PubMed

    Girgih, Abraham T; Chao, Dongfang; Lin, Lin; He, Rong; Jung, Stephanie; Aluko, Rotimi E

    2015-12-01

    Isolated pea protein (IPP) dispersions (1%, w/v) were pretreated with high pressure (HP) of 200, 400, or 600 MPa for 5 min at 24 C or high temperature (HT) for 30 min at 100 C prior to hydrolysis with 1% (w/w) Alcalase. HP pretreatment of IPP at 400 and 600 MPa levels led to significantly (P<0.05) improved (>40%) oxygen radical absorption capacity (ORAC) of hydrolysates. 2,2-Diphenyl-1-picrylhydrazyl, superoxide radical and hydroxyl radical scavenging activities of pea protein hydrolysates were also significantly (P<0.05) improved (25%, 20%, and 40%, respectively) by HP pretreatment of IPP. Protein hydrolysates from HT IPP showed no ORAC, superoxide or hydroxyl scavenging activity but had significantly (P<0.05) improved (80%) ferric reducing antioxidant power. The protein hydrolysates had weaker antioxidant properties than glutathione but overall, the HP pretreatment was superior to HT pretreatment in facilitating enzymatic release of antioxidant peptides from IPP. PMID:26041225

  10. Characterization and Bioactivity of Hydrolysates produced from Aflatoxin Contaminated Peanut Meal

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Justification: Interest in protein hydrolysates is increasing because of their improved functionality and health benefits, particularly angiotensin-converting enzyme (ACE) inhibition, compared to their parent proteins. Large-scale production of hydrolysates is expensive, and one way to minimize co...

  11. Antioxidant mechanisms of caseinophosphopeptides and casein hydrolysates and their application in ground beef.

    PubMed

    Díaz, Mariana; Decker, Eric A

    2004-12-29

    Caseinophosphopeptides (CPP) and casein hydrolysates have been shown to bind prooxidant metals such as iron, but their effectiveness as metal chelators to inhibit lipid oxidation in foods has still not been fully investigated. Thus, the antioxidant activity of CPP and casein hydrolysates was studied in phosphatidylcholine liposome model systems. CPP (< 1.0 mg/mL) and casein hydrolysates (0.3-1.7 mg/mL) were effective inhibitors of TBARS development when oxidation was promoted by ferric/ascorbate. High amounts of CPP (> 1.0 mg/mL) were prooxidant, whereas casein hydrolysates were observed to be only antioxidative. In the presence of peroxyl radicals, casein hydrolysates were more effective scavengers than enriched CPP (3-15 mM). In cooked ground beef, TBARS formation was inhibited 75, 39, and 17% by 0.5% enriched CPP, casein hydrolysates, and low molecular weight casein hydrolysates, respectively, after 4 days of storage. The results show that CPP and casein hydrolysates are promising sources of natural antioxidants for foods. PMID:15612819

  12. Nutritional evaluation of caseins and whey proteins and their hydrolysates from Protamex.

    PubMed

    Sindayikengera, Séverin; Xia, Wen-shui

    2006-02-01

    Whey protein concentrate (WPC 80) and sodium caseinate were hydrolyzed by Protamex to 5%, 10%, 15%, and 20% degree of hydrolysis (DH). WPC 80, sodium caseinate and their hydrolysates were then analyzed, compared and evaluated for their nutritional qualities. Their chemical composition, protein solubility, amino acid composition, essential amino acid index (EAA index), biological value (BV), nutritional index (NI), chemical score, enzymic protein efficiency ratio (E-PER) and in vitro protein digestibility (IVPD) were determined. The results indicated that the enzymatic hydrolysis of WPC 80 and sodium caseinate by Protamex improved the solubility and IVPD of their hydrolysates. WPC 80, sodium caseinate and their hydrolysates were high-quality proteins and had a surplus of essential amino acids compared with the FAO/WHO/UNU (1985) reference standard. The nutritive value of WPC 80 and its hydrolysates was superior to that of sodium caseinate and its hydrolysates as indicated by some nutritional parameters such as the amino acid composition, chemical score, EAA index and predicted BV. However, the E-PER was lower for the WPC hydrolysates as compared to unhydrolyzed WPC 80 but sodium caseinate and its hydrolysates did not differ significantly. The nutritional qualities of WPC 80, sodium caseinate and their hydrolysates were good and make them appropriate for food formulations or as nutritional supplements. PMID:16421963

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

    PubMed

    Seo, Hyeon-Beom; Kim, Seungseop; Lee, Hyeon-Yong; Jung, Kyung-Hwan

    2009-06-01

    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

  14. Dipeptidyl peptidase IV inhibitory and antioxidative properties of milk protein-derived dipeptides and hydrolysates.

    PubMed

    Nongonierma, Alice B; FitzGerald, Richard J

    2013-01-01

    Selected synthetic dipeptides and milk protein hydrolysates were evaluated for their dipeptidyl peptidase IV (DPP-IV) inhibitory properties, and their superoxide (SO) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activities. DPP-IV inhibition was seen with eight out of the twelve dipeptides and 5 of the twelve hydrolysates studied. Trp-Val inhibited DPP-IV, however, inhibition was not observed with the reverse peptide Val-Trp. The most potent hydrolysate inhibitors were generated from casein (CasH2) and lactoferrin (LFH1). Two Trp containing dipeptides, Trp-Val and Val-Trp, and three lactoferrin hydrolysates scavenged DPPH. The dipeptides had higher SO EC(50) values compared to the milk protein hydrolysates (arising from three lactoferrin and one whey protein hydrolysates). Higher molecular mass fractions of the milk protein hydrolysates were associated with the SO scavenging activity. Trp-Val and one lactoferrin hydrolysate (LFH1) were multifunctional displaying both DPP-IV inhibitory and antioxidant (SO and DPPH scavenging) activities. These compounds may have potential as dietary ingredients in the management of type 2 diabetes by virtue of their ability to scavenge reactive oxygen species and to extend the half-life of incretin molecules. PMID:23219487

  15. FISH MEALS, FISH COMPONENTS, AND FISH PROTEIN HYDROLYSATES AS POTENTIAL INGREDIENTS IN PET FOODS.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    An experiment to determine the chemical composition and protein quality of thirteen fish substrates (pollock by-products, fish protein hydrolysates, and fish meals) was conducted, as was an experiment to determine palatability of two of these substrates, salmon protein hydrolysate and salmon meal wi...

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

    PubMed Central

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

    2009-01-01

    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

  17. Determination of oestrogen concentrations in bovine plasma by a recombinant oestrogen receptor-reporter gene yeast bioassay.

    PubMed

    Burdge, G C; Coldham, N G; Dave, M; Sauer, M J; Bleach, E C

    1998-12-01

    A recombinant cell yeast bioassay (RCBA) was applied to the generic measurement of bovine plasma oestrogen concentration. Samples were prepared by diethyl ether extraction of plasma following addition of [3H]17 beta-oestradiol as internal standard; organic and aqueous phases were separated by freezing (recovery 97.1 +/- 0.7%) and dried extract reconstituted in culture medium (recovery 31.4 +/- 4.5%). Plasma oestrogen concentrations were measured by incubation of extracts with yeast containing a stable human oestrogen receptor (hER) and a reporter construct comprising an hER response element regulating beta-galactosidase expression. The linearity of response for the analysis of spiked plasma samples using the RCBA, following corrections, is described by y = 0.8994x - 0.111 (r2 = 0.9776, P < 0.0001). Inter-assay variation for endogenous oestrogen was 11.5% for > 1 pg ml-1. Plasma oestrogen concentrations for intact (n = 5) and castrated (n = 3) males were < 0.5 pg ml-1, and 3.7 +/- 2.6 pg ml-1 for luteal phase females (n = 10). Analysis by RCBA of sequential samples from heifers during the reproductive cycle failed to detect the pre-ovulatory increase in plasma 17 beta-oestradiol as determined by radioimmunoassay (RIA) (maximal concentrations 2.09 +/- 2.1 pg ml-1 and 32.6 +/- 14.6 pg ml-1, respectively). Interestingly, when samples were hydrolysed using Helix pomatia glucuronidase the RCBA gave concentrations (29.5 +/- 8.9 pg ml-1) not significantly different to those obtained by RIA. These preliminary findings suggest that a substantial proportion of plasma oestrogen during the pre-ovulatory period may be conjugated. These data indicate the potential of the RCBA to measure biologically active and physiological levels of plasma oestrogens in cattle. One potentially valuable application of this generic oestrogen assay could be in surveillance programmes to detect illegal use of anabolic oestrogens in live-stock where the identity of the analyte may be unknown. PMID:10435304

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

    PubMed

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

    2014-07-01

    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

  19. Antioxidant activity of bovine casein hydrolysates produced by Ficus carica L.-derived proteinase.

    PubMed

    Di Pierro, Giovanna; O'Keeffe, Martina B; Poyarkov, Alexey; Lomolino, Giovanna; FitzGerald, Richard J

    2014-08-01

    A Ficus carica L. latex proteinase preparation was investigated for its ability to produce antioxidant hydrolysates/peptides from bovine casein (CN). The Oxygen Radical Absorbance Capacity (ORAC) values for NaCN and β-CN hydrolysates ranged from 0.06 to 0.18, and from 0.51 to 1.19μmol Trolox equivalents/mg freeze-dried sample, respectively. Gel permeation HPLC showed that the β-CN hydrolysate with a degree of hydrolysis of 21% had 65% of peptide material with a molecular mass <500Da. The RP-UPLC profiles also indicated that β-CN was substantially hydrolysed during the early stages of hydrolysis. Analysis of the 4h β-CN hydrolysate by LC-ESI-MS/MS allowed identification of 8 peptide sequences with potential antioxidant properties. PMID:24629973

  20. Continuous ethanol production from concentrated wood hydrolysates in an internal membrane-filtration bioreactor

    SciTech Connect

    Lee, W.G.; Park, B.G.; Chang, Y.K.; Chang, H.N.; Lee, J.S.; Park, S.C.

    2000-04-01

    Continuous culture for the production of ethanol from wood hydrolysate was carried out in an internal membrane-filtration bioreactor. The hydrolysate medium was sterilized at a relatively low temperature of 60 C with the intention of reducing the formation of inhibitory compounds during the sterilization. The maximum ethanol concentration and productivity obtained in this study were 76.9 g/L and 16.9 g/L-h, respectively, which were much higher than those obtained in batch cultures using hydrolysate media sterilized at 60 C. The productivity was also found to be much higher than that obtained in a continuous cell retention culture using a wood hydrolysate sterilized at 121 C. These results show that the internal membrane-filtration bioreactor in combination with low-temperature sterilization could be very effective for ethanol production from wood hydrolysate.

  1. Vaginal Yeast Infection

    MedlinePlus

    ... to thick. Most male partners of women with yeast infections do not have any symptoms of the infection. Some men, however, have reported temporary rashes and burning sensations of the penis after intercourse if they did not use condoms. ...

  2. Vaginal yeast infection

    MedlinePlus

    ... pregnant You are obese You have diabetes A yeast infection is not spread through sexual contact. However, some men will develop symptoms such as itching and a rash on the penis after having sexual contact with an infected partner. ...

  3. Replicative Aging in Yeast

    PubMed Central

    Steinkraus, K.A.; Kaeberlein, M.; Kennedy, B.K.

    2009-01-01

    Progress in aging research is now rapid, and surprisingly, studies in a single-celled eukaryote are a driving force. The genetic modulators of replicative life span in yeast are being identified, the molecular events that accompany aging are being discovered, and the extent to which longevity pathways are conserved between yeast and multicellular eukaryotes is being tested. In this review, we provide a brief retrospective view on the development of yeast as a model for aging and then turn to recent discoveries that have pushed aging research into novel directions and also linked aging in yeast to well-developed hypotheses in mammals. Although the question of what causes aging still cannot be answered definitively, that day may be rapidly approaching. PMID:18616424

  4. RNAi in budding yeast

    PubMed Central

    Mower, Jeffrey P.; Wolfe, Kenneth H.; Fink, Gerald R.; Bartel, David P.

    2013-01-01

    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 siRNAs, which mostly correspond to transposable elements and Y’ subtelomeric repeats. In S. castellii, RNAi mutants are viable but have excess Y’ mRNA levels. In S. cerevisiae, introducing Dicer and Argonaute of S. castellii restores RNAi, and the reconstituted pathway silences endogenous retrotransposons. These results identify a novel 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

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

    PubMed

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

    2011-04-01

    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

  6. Yeast Biomass Production in Brewery's Spent Grains Hemicellulosic Hydrolyzate

    NASA Astrophysics Data System (ADS)

    Duarte, Luís C.; Carvalheiro, Florbela; Lopes, Sónia; Neves, Ines; Gírio, Francisco M.

    Yeast single-cell protein and yeast extract, in particular, are two products which have many feed, food, pharmaceutical, and biotechnological applications. However, many of these applications are limited by their market price. Specifically, the yeast extract requirements for culture media are one of the major technical hurdles to be overcome for the development of low-cost fermentation routes for several top value chemicals in a biorefinery framework. A potential biotechnical solution is the production of yeast biomass from the hemicellulosic fraction stream. The growth of three pentose-assimilating yeast cell factories, Debaryomyces hansenii, Kluyveromyces marxianus, and Pichia stipitis was compared using non-detoxified brewery's spent grains hemicellulosic hydrolyzate supplemented with mineral nutrients. The yeasts exhibited different specific growth rates, biomass productivities, and yields being D. hansenii as the yeast species that presented the best performance, assimilating all sugars and noteworthy consuming most of the hydrolyzate inhibitors. Under optimized conditions, D. hansenii displayed a maximum specific growth rate, biomass yield, and productivity of 0.34 h-1, 0.61 g g-1, and 0.56 g 1-1 h-1, respectively. The nutritional profile of D. hansenii was thoroughly evaluated, and it compares favorably to others reported in literature. It contains considerable amounts of some essential amino acids and a high ratio of unsaturated over saturated fatty acids.

  7. Nitrile Metabolizing Yeasts

    NASA Astrophysics Data System (ADS)

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

    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.

  8. Modeling brewers' yeast flocculation

    PubMed

    van Hamersveld EH; van der Lans RG; Caulet; Luyben

    1998-02-01

    Flocculation of yeast cells occurs during the fermentation of beer. Partway through the fermentation the cells become flocculent and start to form flocs. If the environmental conditions, such as medium composition and fluid velocities in the tank, are optimal, the flocs will grow in size large enough to settle. After settling of the main part of the yeast the green beer is left, containing only a small amount of yeast necessary for rest conversions during the next process step, the lagering. The physical process of flocculation is a dynamic equilibrium of floc formation and floc breakup resulting in a bimodal size distribution containing single cells and flocs. The floc size distribution and the single cell amount were measured under the different conditions that occur during full scale fermentation. Influences on flocculation such as floc strength, specific power input, and total number of yeast cells in suspension were studied. A flocculation model was developed, and the measured data used for validation. Yeast floc formation can be described with the collision theory assuming a constant collision efficiency. The breakup of flocs appears to occur mainly via two mechanisms, the splitting of flocs and the erosion of yeast cells from the floc surface. The splitting rate determines the average floc size and the erosion rate determines the number of single cells. Regarding the size of the flocs with respect to the scale of turbulence, only the viscous subrange needs to be considered. With the model, the floc size distribution and the number of single cells can be predicted at a certain point during the fermentation. For this, the bond strength between the cells, the fractal dimension of the yeast, the specific power input in the tank and the number of yeast cells that are in suspension in the tank have to be known. Copyright 1998 John Wiley & Sons, Inc. PMID:10099210

  9. Structural and Antihypertensive Properties of Enzymatic Hemp Seed Protein Hydrolysates.

    PubMed

    Malomo, Sunday A; Onuh, John O; Girgih, Abraham T; Aluko, Rotimi E

    2015-09-01

    The aim of this work was to produce antihypertensive protein hydrolysates through different forms of enzymatic hydrolysis (2% pepsin, 4% pepsin, 1% alcalase, 2% alcalase, 2% papain, and 2% pepsin + pancreatin) of hemp seed proteins (HSP). The hemp seed protein hydrolysates (HPHs) were tested for in vitro inhibitions of renin and angiotensin-converting enzyme (ACE), two of the enzymes that regulate human blood pressure. The HPHs were then administered orally (200 mg/kg body weight) to spontaneously hypertensive rats and systolic blood pressure (SBP)-lowering effects measured over a 24 h period. Size exclusion chromatography mainly showed a 300-9560 Da peptide size range for the HPHs, while amino acid composition data had the 2% pepsin HPH with the highest cysteine content. Fluorescence spectroscopy revealed higher fluorescence intensities for the peptides when compared to the unhydrolyzed hemp seed protein. Overall, the 1% alcalase HPH was the most effective (p < 0.05) SBP-reducing agent (-32.5 ± 0.7 mmHg after 4 h), while the pepsin HPHs produced longer-lasting effects (-23.0 ± 1.4 mmHg after 24 h). We conclude that an optimized combination of the fast-acting HPH (1% alcalase) with the longer-lasting HPHs (2% and 4% pepsin) could provide daily effective SBP reductions. PMID:26378569

  10. Lignocellulosic hydrolysate inhibitors selectively inhibit/deactivate cellulase performance.

    PubMed

    Mhlongo, Sizwe I; den Haan, Riaan; Viljoen-Bloom, Marinda; van Zyl, Willem H

    2015-12-01

    In this study, we monitored the inhibition and deactivation effects of various compounds associated with lignocellulosic hydrolysates on individual and combinations of cellulases. Tannic acid representing polymeric lignin residues strongly inhibited cellobiohydrolase 1 (CBH1) and β-glucosidase 1 (BGL1), but had a moderate inhibitory effect on endoglucanase 2 (EG2). Individual monomeric lignin residues had little or no inhibitory effect on hydrolytic enzymes. However, coniferyl aldehyde and syringaldehyde substantially decreased the activity of CBH1 and deactivated BGL1. Acetic and formic acids also showed strong inhibition of BGL1 but not CBH1 and EG2, whereas tannic, acetic and formic acid strongly inhibited a combination of CBH1 and EG2 during Avicel hydrolysis. Diminishing enzymatic hydrolysis is largely a function of inhibitor concentration and the enzyme-inhibitor relationship, rather than contact time during the hydrolysis process (i.e. deactivation). This suggests that decreased rates of hydrolysis during the enzymatic depolymerisation of lignocellulosic hydrolysates may be imparted by other factors related to substrate crystallinity and accessibility. PMID:26453468

  11. Antioxidative activity of whey protein hydrolysates in a liposomal system.

    PubMed

    Peña-Ramos, E A; Xiong, Y L

    2001-12-01

    Whey protein isolate (WPI) with or without preheating (90 degrees C for 5 min) was hydrolyzed for 0.5 to 6 h using four pure enzymes (pepsin, papain, trypsin, and chymotrypsin) and three commercial crude proteases. After determining the degree of hydrolysis, the hydrolysates were incubated (37 degrees C, 1 h) with a liposome oxidizing system (50 mM FeCl3/0.1 mM ascorbate, pH 7.0). Lipid oxidation was measured by determining the concentrations of TBA-reactive substances (TBARS). The degree of hydrolysis of WPI ranged from 4 to 37% depending on the enzymes used and whether the substrate was heated or not. WPI hydrolysates prepared by pure enzyme treatments did not prevent TBARS formation in the oxidative model system, but WPI hydrolyzed by the commercial crude enzymes, especially protease F, exhibited antioxidant activity. The antioxidative potential of hydrolyzed WPI was not affected by the degree of hydrolysis, and it was improved by preheat treatment in only some samples. PMID:11814013

  12. Structural and Antihypertensive Properties of Enzymatic Hemp Seed Protein Hydrolysates

    PubMed Central

    Malomo, Sunday A.; Onuh, John O.; Girgih, Abraham T.; Aluko, Rotimi E.

    2015-01-01

    The aim of this work was to produce antihypertensive protein hydrolysates through different forms of enzymatic hydrolysis (2% pepsin, 4% pepsin, 1% alcalase, 2% alcalase, 2% papain, and 2% pepsin + pancreatin) of hemp seed proteins (HSP). The hemp seed protein hydrolysates (HPHs) were tested for in vitro inhibitions of renin and angiotensin-converting enzyme (ACE), two of the enzymes that regulate human blood pressure. The HPHs were then administered orally (200 mg/kg body weight) to spontaneously hypertensive rats and systolic blood pressure (SBP)-lowering effects measured over a 24 h period. Size exclusion chromatography mainly showed a 300–9560 Da peptide size range for the HPHs, while amino acid composition data had the 2% pepsin HPH with the highest cysteine content. Fluorescence spectroscopy revealed higher fluorescence intensities for the peptides when compared to the unhydrolyzed hemp seed protein. Overall, the 1% alcalase HPH was the most effective (p < 0.05) SBP-reducing agent (−32.5 ± 0.7 mmHg after 4 h), while the pepsin HPHs produced longer-lasting effects (−23.0 ± 1.4 mmHg after 24 h). We conclude that an optimized combination of the fast-acting HPH (1% alcalase) with the longer-lasting HPHs (2% and 4% pepsin) could provide daily effective SBP reductions. PMID:26378569

  13. Isolation of microorganisms for biological detoxification of lignocellulosic hydrolysates.

    PubMed

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

    2004-03-01

    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 (5 mM), 5-hydroxymethylfurfural (5-HMF, 15 mM), and furfural (20 mM) as the carbon and energy sources, followed by an additional transfer into a corn stover hydrolysate (CSH) prepared using dilute acid. Subsequently, based on stable growth on these substrates, six isolates--including five bacteria related to Methylobacterium extorquens, Pseudomonas sp, Flavobacterium indologenes, Acinetobacter sp., Arthrobacter aurescens, and one fungus, Coniochaeta ligniaria--were chosen. All six isolates depleted toxic compounds from defined medium, but only C. ligniaria C8 (NRRL 30616) was effective at eliminating furfural and 5-HMF from CSH. C. ligniaria NRRL 30616 may be useful in developing a bioprocess for inhibitor abatement in the conversion of lignocellulosic biomass to fuels and chemicals. PMID:12908085

  14. Bacteria and yeast cell disruption using lytic enzymes.

    PubMed

    Salazar, Oriana

    2008-01-01

    Enzymatic methods provide a convenient alternative for overcoming technical disadvantages of mechanical disruption. Protocols for protein extraction from bacteria and Saccharomyces cerevisiae using lytic enzymes are presented in this chapter. Adaptation of the yeast protocol to a microtiter plate format makes this protocol amenable for proteomic applications and high-throughput screening of libraries expressing genetic variants in yeast. This methodology can also be applied to bacteria. PMID:18369849

  15. Forces in yeast flocculation

    NASA Astrophysics Data System (ADS)

    El-Kirat-Chatel, Sofiane; Beaussart, Audrey; Vincent, Stéphane P.; Abellán Flos, Marta; Hols, Pascal; Lipke, Peter N.; Dufrêne, Yves F.

    2015-01-01

    In the baker's yeast Saccharomyces cerevisiae, cell-cell adhesion (``flocculation'') is conferred by a family of lectin-like proteins known as the flocculin (Flo) proteins. Knowledge of the adhesive and mechanical properties of flocculins is important for understanding the mechanisms of yeast adhesion, and may help controlling yeast behaviour in biotechnology. We use single-molecule and single-cell atomic force microscopy (AFM) to explore the nanoscale forces engaged in yeast flocculation, focusing on the role of Flo1 as a prototype of flocculins. Using AFM tips labelled with mannose, we detect single flocculins on Flo1-expressing cells, showing they are widely exposed on the cell surface. When subjected to force, individual Flo1 proteins display two distinct force responses, i.e. weak lectin binding forces and strong unfolding forces reflecting the force-induced extension of hydrophobic tandem repeats. We demonstrate that cell-cell adhesion bonds also involve multiple weak lectin interactions together with strong unfolding forces, both associated with Flo1 molecules. Single-molecule and single-cell data correlate with microscale cell adhesion behaviour, suggesting strongly that Flo1 mechanics is critical for yeast flocculation. These results favour a model in which not only weak lectin-sugar interactions are involved in yeast flocculation but also strong hydrophobic interactions resulting from protein unfolding.

  16. Using Microsatellites to Identify Yeast Strains in Beer

    PubMed Central

    Bruke, Alexandria; Van Brocklin, Jennifer; Rivest, Jason; Prenni, Jessica E.; Ibrahim, Hend

    2012-01-01

    Yeast is an integral part of the brewing process and is responsible for much of the taste and characteristics of beer. During the brewing process, yeast is subject to ageing and stress factors that can result in growth inhibition, decreased genetic stability, and changes in cell membrane stability. Characterization of yeast species used in industrial fermentation (e.g. S. cerevisiae) is of great importance to the brewing industry. The objective of this study was to develop an assay to identify yeast strains commonly used in the production of beer. Six microsatellite regions of DNA (comprised of AAT) were used as sequence tagged site markers (STR) to identify and compare yeast samples and to determine strain within a species. Labeled primers ScATT (1-6) targeting these six microsatellite regions were designed using 6-FAM, VIC, NED and PET 5′-fluorescent labels. The six regions were amplified, in a single reaction, from extracted yeast genomic DNA using a modified multiplex-PCR protocol and the labeled PCR products were analyzed on an ABI 3130xl Genetic Analyzer. Using this approach 6 STR markers were amplified in a single multiplex reaction from a commercially utilized yeast strain provided by Odell Brewing. Different alleles were distinguished based on the size of each STR and the labeling fluorophore. The procedures developed in this study will provide an invaluable tool for the quality control of yeast strains in the brewing industry.

  17. Purification and identification of Se-containing antioxidative peptides from enzymatic hydrolysates of Se-enriched brown rice protein.

    PubMed

    Liu, Kunlun; Zhao, Yan; Chen, Fusheng; Fang, Yong

    2015-11-15

    As a further study of Se-containing proteins (Se-Pro) derived from Se-enriched brown rice (Se-BR), this paper aimed to purify and identify Se-containing antioxidative peptides (Se-antioxi-Peps) from Se-Pro hydrolysates. The total Se content in Se-BR was 6.26μg/g DW, and selenocystine, Se-methylselenocysteine, and selenomethionine were identified as the main organic Se species by high-performance liquid chromatography-inductively coupled plasma mass spectrometry. Se-Pro was extracted and hydrolyzed by four types of proteases, and Alcalase was chosen as the optimum enzyme according to the degree of hydrolysis (DH). The hydrolysate with 17.08% DH possessing the highest DPPH radical scavenging activity was separated into five fractions (F1 to F5). Fractions F3 to F5, which had high antioxidative activities, were further separated. Sub-fractions F3-3, F4-2, and F5-1 were chosen to evaluate antioxidative activities and analyze Se species. The Se-antioxi-Pep with the sequence SeMet-Pro-Ser was identified by electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry. PMID:25977046

  18. High-performance liquid chromatography method for the simultaneous quantification of retinol, alpha-tocopherol, and cholesterol in shrimp waste hydrolysate.

    PubMed

    López-Cervantes, J; Sánchez-Machado, D I; Ríos-Vázquez, N J

    2006-02-10

    This study presents an HPLC method for the simultaneous quantification of retinol, alpha-tocopherol, and cholesterol in shrimp waste hydrolysate lipid fraction. The method includes microscale saponification and extraction with n-hexane. Liposoluble vitamins and cholesterol were quantified by HPLC with UV detection (HPLC-UV), on a 25 cm x 0.46 cm SS Exil ODS 5 microm column, mobile phase 68:28:4 (v/v/v) methanol:acetonitrile:water; flow rate 1.4 ml/min; column temperature 36 degrees C. The detection was operated using two channels of a diode-array spectrophotometer, 325 nm for retinol and 208 nm for alpha-tocopherol and cholesterol. With these conditions, the overall recovery was 95.7, 100.8, and 98.0% for retinol, alpha-tocopherol, and cholesterol, respectively. The method precision (relative standard deviation) was 1.83% for retinol, 2.32% for alpha-tocopherol, and 1.98% for cholesterol. This method was used to quantify the cited analytes in the hydrolysate obtained during lactic acid fermentation of shrimp waste. This hydrolysate may be a valuable supplement of nutrients in fish production. PMID:16439259

  19. Fermentation of reactive-membrane-extracted and ammonium-hydroxide-conditioned dilute-acid-pretreated corn stover.

    PubMed

    Grzenia, David L; Wickramasinghe, S Ranil; Schell, Daniel J

    2012-01-01

    Acid-pretreated biomass contains various compounds (acetic acid, etc.) that are inhibitory to fermentative microorganisms. Removing or deactivating these compounds using detoxification methods such as overliming or ammonium hydroxide conditioning (AHC) improves sugar-to-ethanol yields. In this study, we treated the liquor fraction of dilute-acid-pretreated corn stover using AHC and a new reactive membrane extraction technique, both separately and in combination, and then the sugars in the treated liquors were fermented to ethanol with the glucose-xylose-fermenting bacterium, Zymomonas mobilis 8b. We performed reactive extraction with mixtures of octanol/Alamine 336 or oleyl alcohol/Alamine 336. The best ethanol yields and rates were achieved for oleyl alcohol-extracted hydrolysates followed by AHC hydrolysates, while octanol-extracted hydrolysates were unfermentable because highly toxic octanol was found in the hydrolysate. Adding olive oil significantly improved yields for octanol-extracted hydrolysate. Additional work is underway to determine if this technology is a cost-effective alternative to traditional hydrolysate conditioning processes. PMID:22161211

  20. Development of a practical and cost-effective medium for bioethanol production from the seaweed hydrolysate in surface-aerated fermentor by repeated-batch operation.

    PubMed

    Lee, Sang-Eun; Lee, Ji-Eun; Shin, Ga-Young; Choi, Woon Yong; Kang, Do Hyung; Lee, Hyeon-Yong; Jung, Kyung-Hwan

    2012-01-01

    To develop a practical and cost-effective medium for bioethanol production from the hydrolysate of seaweed Sargassum sagamianum, we investigated the feasibility and performance of bioethanol production in CSL (cornsteep liquor)-containing medium, where yeast Pichia stipitis was used and the repeated batch was carried out in a surface-aerated fermentor. The optimal medium replacement time during the repeated operation was determined to be 36 h, and the surface aeration rates were 30 and 100 ml/min. Under these conditions, the repeatedbatch operation was successfully carried out for 6 runs (216 h), in which the maximum bioethanol concentrations reached about 11-12 g/l at each batch operation. These results demonstrated that bioethanol production could be carried out repeatedly and steadily for 216 h. In these experiments, the total cumulative bioethanol production was 57.9 g and 58.0 g when the surface aeration rates were 30 ml/min and 100 ml/min, respectively. In addition, the bioethanol yields were 0.43 (about 84% of theoretical value) and 0.44 (about 86% of theoretical value) when the surface aeration rates were 30 ml/min and 100 ml/min, respectively. CSL was successfully used as a medium ingredient for the bioethanol production from the hydrolysate of seaweed Sargassum sagamianum, indicating that this medium may be practical and cost-effective for bioethanol production. PMID:22297226

  1. Identification of Small Aliphatic Aldehydes in Pretreated Lignocellulosic Feedstocks and Evaluation of Their Inhibitory Effects on Yeast.

    PubMed

    Cavka, Adnan; Stagge, Stefan; Jnsson, Leif J

    2015-11-11

    Six lignocellulosic hydrolysates produced through acid pretreatment were analyzed for the occurrence of formaldehyde, acetaldehyde, and glycolaldehyde. Acetaldehyde was found in all six (0.3-1.6 mM) and formaldehyde in four (? 4.4 mM), whereas glycolaldehyde was not detected. To assess the relevance of these findings, fermentations with yeast and formaldehyde or acetaldehyde were performed in the concentration interval 0.5-10 mM. Formaldehyde already inhibited at 1.0 mM, whereas 5.0 mM acetaldehyde was needed to obtain a clear inhibitory effect. After 24 h of fermentation, 1.5 mM formaldehyde reduced the glucose consumption by 85%, the balanced ethanol yield by 92%, and the volumetric productivity by 91%. The results show that formaldehyde and acetaldehyde are prevalent in pretreated lignocellulose and that formaldehyde in some cases could explain a large part of the inhibitory effects on yeast by lignocellulosic hydrolysates, as three of six hydrolysates contained ? 1.9 mM formaldehyde, which was shown to be strongly inhibitory. PMID:26528761

  2. Factors causing compositional changes in soy protein hydrolysates and effects on cell culture functionality.

    PubMed

    Gupta, Abhishek J; Gruppen, Harry; Maes, Dominick; Boots, Jan-Willem; Wierenga, Peter A

    2013-11-13

    Soy protein hydrolysates significantly enhance cell growth and recombinant protein production in cell cultures. The extent of this enhancement in cell growth and IgG production is known to vary from batch to batch. This can be due to differences in the abundance of different classes of compounds (e.g., peptide content), the quality of these compounds (e.g., glycated peptides), or the presence of specific compounds (e.g., furosine). These quantitative and qualitative differences between batches of hydrolysates result from variation in the seed composition and seed/meal processing. Although a considerable amount of literature is available that describes these factors, this knowledge has not been combined in an overview yet. The aim of this review is to identify the most dominant factors that affect hydrolysate composition and functionality. Although there is a limited influence of variation in the seed composition, the overview shows that the qualitative changes in hydrolysate composition result in the formation of minor compounds (e.g., Maillard reaction products). In pure systems, these compounds have a profound effect on the cell culture functionality. This suggests that the presence of these compounds in soy protein hydrolysates may affect hydrolysate functionality as well. This influence on the functionality can be of direct or indirect nature. For instance, some minor compounds (e.g., Maillard reaction products) are cytotoxic, whereas other compounds (e.g., phytates) suppress protein hydrolysis during hydrolysate production, resulting in altered peptide composition, and, thus, affect the functionality. PMID:24117369

  3. Characterization of structural and functional properties of fish protein hydrolysates from surimi processing by-products.

    PubMed

    Liu, Yongle; Li, Xianghong; Chen, Zhijun; Yu, Jian; Wang, Faxiang; Wang, Jianhui

    2014-05-15

    Structural and functional properties of fish protein hydrolysates with different degrees of hydrolysis (DH) from surimi processing by-products, prepared by Protamex and Alcalase, were evaluated. As the DH increased, the zeta potentials of the hydrolysates increased (p>0.05). The surface hydrophobicity of the hydrolysates was significantly affected by DH (p<0.05). A wide variety of peptides were obtained after hydrolysis by Protamex and Alcalase. The hydrolysate with DH 10%, prepared by Protamex, contained more large protein molecules than did the others. Hydrolysis by both enzymes increased solubility to more than 65% over a wide pH range (pH 2-10). The interfacial activities of hydrolysates decreased with increasing DH (p<0.05). The hydrolysate with DH 10%, prepared by Protamex, exhibited the best interfacial properties among all of the samples. Thermal properties were also affected by the hydrolysis. The results reveal that structures and functionalities of the hydrolysates were determined both by DH and enzyme type employed. PMID:24423557

  4. Antioxidant activities of red tilapia (Oreochromis niloticus) protein hydrolysates as influenced by thermolysin and alcalase

    NASA Astrophysics Data System (ADS)

    Daud, Nur'Aliah; Babji, Abdul Salam; Yusop, Salma Mohamad

    2013-11-01

    The hydrolysis process was performed on fish meat from Red Tilapia (Oreochromis niloticus) by enzymes thermolysin and alcalase under optimum conditions. The hydrolysis was performed from 0 - 4 hours at 37°C. Hydrolysates after 2 hours incubation with thermolysin and alcalase had degree of hydrolysis of 76.29 % and 63.49 %, respectively. The freeze dried protein hydrolysate was tested for peptide content and characterized with respect to amino acid composition. The result of increased peptide content in Red Tilapia (O. Niloticus) hydrolysates obtained was directly proportional to the increase activities of different proteolytic enzymes. The result of amino acid composition showed that the sample used contained abundant Gly, Ala, Asp, Glu, Lys and Leu in residues or peptide sequences. Both enzymatic hydrolysates were tested for anti-oxidant activity with DPPH and ABTS assay. Alcalase yielded higher anti-oxidative activity than Thermolysin hydrolysates after 1 hour incubation, but both enzymes hydrolysates showed a significant decrease of anti-oxidant activity after 2 hours of incubation. Hydrolysates from Red Tilapia may contribute as a health promoting ingredient in functional foods to reduce oxidation stress caused by accumulated free radicals.

  5. Antioxidant activities of bambara groundnut (Vigna subterranea) protein hydrolysates and their membrane ultrafiltration fractions.

    PubMed

    Arise, Abimbola K; Alashi, Adeola M; Nwachukwu, Ifeanyi D; Ijabadeniyi, Oluwatosin A; Aluko, Rotimi E; Amonsou, Eric O

    2016-05-18

    In this study, the bambara protein isolate (BPI) was digested with three proteases (alcalase, trypsin and pepsin), to produce bambara protein hydrolysates (BPHs). These hydrolysates were passed through ultrafiltration membranes to obtain peptide fractions of different sizes (<1, 1-3, 3-5 and 5-10 kDa). The hydrolysates and their peptide fractions were investigated for antioxidant activities. The membrane fractions showed that peptides with sizes <3 kDa had significantly (p < 0.05) reduced surface hydrophobicity when compared with peptides >3 kDa. This is in agreement with the result obtained for the ferric reducing power, metal chelating and hydroxyl radical scavenging activities where higher molecular weight peptides exhibited better activity (p < 0.05) when compared to low molecular weight peptide fractions. However, for all the hydrolysates, the low molecular weight peptides were more effective diphenyl-1-picrylhydrazyl (DPPH) radical scavengers but not superoxide radicals when compared to the bigger peptides. In comparison with glutathione (GSH), BPHs and their membrane fractions had better (p < 0.05) reducing power and ability to chelate metal ions except for the pepsin hydrolysate and its membrane fractions that did not show any metal chelating activity. However, the 5-10 kDa pepsin hydrolysate peptide fractions had greater (88%) hydroxyl scavenging activity than GSH, alcalase and trypsin hydrolysates (82%). These findings show the potential use of BPHs and their peptide fraction as antioxidants in reducing food spoilage or management of oxidative stress-related metabolic disorders. PMID:27156453

  6. Generation, Fractionation, and Characterization of Iron-Chelating Protein Hydrolysate from Palm Kernel Cake Proteins.

    PubMed

    Zarei, Mohammad; Ghanbari, Rahele; Tajabadi, Naser; Abdul-Hamid, Azizah; Bakar, Fatimah Abu; Saari, Nazamid

    2016-02-01

    Palm kernel cake protein was hydrolyzed with different proteases namely papain, bromelain, subtilisin, flavourzyme, trypsin, chymotrypsin, and pepsin to generate different protein hydrolysates. Peptide content and iron-chelating activity of each hydrolysate were evaluated using O-phthaldialdehyde-based spectrophotometric method and ferrozine-based colorimetric assay, respectively. The results revealed a positive correlation between peptide contents and iron-chelating activities of the protein hydrolysates. Protein hydrolysate generated by papain exhibited the highest peptide content of 10.5 mM and highest iron-chelating activity of 64.8% compared with the other hydrolysates. Profiling of the papain-generated hydrolysate by reverse phase high performance liquid chromatography fractionation indicated a direct association between peptide content and iron-chelating activity in most of the fractions. Further fractionation using isoelectric focusing also revealed that protein hydrolysate with basic and neutral isoelectric point (pI) had the highest iron-chelating activity, although a few fractions in the acidic range also exhibited good metal chelating potential. After identification and synthesis of papain-generated peptides, GGIF and YLLLK showed among the highest iron-chelating activities of 56% and 53%, whereas their IC50 were 1.4 and 0.2 μM, respectively. PMID:26720491

  7. Xylitol production by yeasts isolated from rotting wood in the Galápagos Islands, Ecuador, and description of Cyberlindnera galapagoensis f.a., sp. nov.

    PubMed

    Guamán-Burneo, Maria C; Dussán, Kelly J; Cadete, Raquel M; Cheab, Monaliza A M; Portero, Patricia; Carvajal-Barriga, Enrique J; da Silva, Sílvio S; Rosa, Carlos A

    2015-10-01

    This study evaluated D-xylose-assimilating yeasts that are associated with rotting wood from the Galápagos Archipelago, Ecuador, for xylitol production from hemicellulose hydrolysates. A total of 140 yeast strains were isolated. Yeasts related to the clades Yamadazyma, Kazachstania, Kurtzmaniella, Lodderomyces, Metschnikowia and Saturnispora were predominant. In culture assays using sugarcane bagasse hemicellulose hydrolysate, Candida tropicalis CLQCA-24SC-125 showed the highest xylitol production, yield and productivity (27.1 g L(-1) xylitol, Y p/s (xyl) = 0.67 g g(-1), Qp = 0.38 g L(-1). A new species of Cyberlindnera, strain CLQCA-24SC-025, was responsible for the second highest xylitol production (24 g L(-1), Y p/s (xyl) = 0.64 g g(-1), Qp = 0.33 g L(-1) h(-1)) on sugarcane hydrolysate. The new xylitol-producing species Cyberlindnera galapagoensis f.a., sp. nov., is proposed to accommodate the strain CLQCA-24SC-025(T) (=UFMG-CM-Y517(T); CBS 13997(T)). The MycoBank number is MB 812171. PMID:26219566

  8. Mapping Yeast Transcriptional Networks

    PubMed Central

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

    2013-01-01

    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

  9. Oxygen requirements of yeasts.

    PubMed Central

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

    1990-01-01

    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

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

    PubMed

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

    2011-01-01

    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

  11. Evaluation of Physicochemical and Antioxidant Properties of Peanut Protein Hydrolysate

    PubMed Central

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

    2012-01-01

    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

  12. Identification of bitter peptides in whey protein hydrolysate.

    PubMed

    Liu, Xiaowei; Jiang, Deshou; Peterson, Devin G

    2014-06-25

    Bitterness of whey protein hydrolysates (WPH) can negatively affect product quality and limit utilization in food and pharmaceutical applications. Four main bitter peptides were identified in a commercial WPH by means of sensory-guided fractionation techniques that included ultrafiltration and offline two-dimensional reverse phase chromatography. LC-TOF-MS/MS analysis revealed the amino acid sequences of the bitter peptides were YGLF, IPAVF, LLF, and YPFPGPIPN that originated from α-lactalbumin, β-lactoglobulin, serum albumin, and β-casein, respectively. Quantitative LC-MS/MS analysis reported the concentrations of YGLF, IPAVF, LLF, and YPFPGPIPN to be 0.66, 0.58, 1.33, and 2.64 g/kg powder, respectively. Taste recombination analysis of an aqueous model consisting of all four peptides was reported to explain 88% of the bitterness intensity of the 10% WPH solution. PMID:23998904

  13. In vitro Antioxidant Activities of Trianthema portulacastrum L. Hydrolysates

    PubMed Central

    Yaqoob, Sadaf; Sultana, Bushra; Mushtaq, Muhammad

    2014-01-01

    Hydrolysates of Trianthema portulacastrum in acidified methanol were evaluated for their total phenolic (TP) constituents and respective antioxidant activities using in vitro assays (i.e., 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity, percent inhibition of linoleic acid peroxidation, and ferric reducing power). The observed results indicate that root, shoot, and leaf fractions of T. portulacastrum contain 50.75~98.09 mg gallic acid equivalents/g dry weight of TP. In addition, these fractions have substantial reducing potentials (0.10~0.59), abilities to inhibit peroxidation (43.26~89.98%), and DPPH radical scavenging capabilities (6.98~311.61 ?g/mL IC50). The experimental data not only reveal T. portulacastrum as potential source of valuable antioxidants, but also indicate that acidified methanol may be an ideal choice for the enhanced recovery of phenolic compounds with retained biological potential for the food and pharmaceutical industry. PMID:24772406

  14. Synthesis of non-hydrolysable mimics of glycosylphosphatidylinositol (GPI) anchors.

    PubMed

    Yadav, Mahipal; Raghupathy, Riya; Saikam, Varma; Dara, Saidulu; Singh, Parvinder Pal; Sawant, Sanghapal D; Mayor, Satyajit; Vishwakarma, Ram A

    2014-02-21

    Synthesis of first generation non-hydrolysable C-phosphonate GPI analogs, viz., 6-O-(2-amino-2-deoxy-α-d-glucopyranosyl)-d-myo-inositol-1-O-(sn-3,4-bis(palmitoyloxy)butyl-1-phosphonate) and 6-O-(2-amino-2-deoxy-α-d-glucopyranosyl)-d-myo-inositol-1-O-(sn-2,3-bis(palmitoyloxy)propyl-1-phosphonate) 23b, is reported. The target compounds were synthesized by the coupling of α-pseudodisaccharide 21 with phosphonic acids 18a and 18b respectively in quantitative yield followed by de-protection. These synthetic C-phosphonate GPI-probes were resistant to phosphatidylinositol specific phospholipase C (PI-PLC) and also showed moderate inhibition of the enzyme activity. PMID:24413835

  15. EFFECT OF STARCH HYDROLYSATES IN THE PROCESS OF DISSOLUTION OF SOLIDS.

    PubMed

    Belniak, Piotr; Świąder, Katarzyna; Szumiło, Michał; Pietrzyk, Ewelina; Poleszak, Ewa

    2015-01-01

    The purpose of this work was to investigate the influence of starch hydrolysates in the dissolution process of the substance practically insoluble in water. Progesterone and ibuprofen were chosen as model substances. The study was conducted with a constant amount of the drug (25 mg/mL) or constant amount of starch hydrolysate (50 mg/mL). Next, the influence of ethanolic solutions (10-30% v/v) on solubility of drug was tested. The results confirm the possibility of using starch hydrolysate as a cheap and safe addition to increase the solubility of practically insoluble drugs. PMID:26647636

  16. Amino Acid Analyses of Acid Hydrolysates in Desert Varnish

    NASA Technical Reports Server (NTRS)

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

    2001-01-01

    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.

  17. [Fructose transporter in yeasts].

    PubMed

    Lazar, Zbigniew; Dobrowolski, Adam; Robak, Małgorzata

    2014-01-01

    Study of hexoses transporter started with discovery of galactose permease in Saccharomyces cerevisiae. Glucose, fructose and mannose assimilation is assumed by numerous proteins encoded by different genes. To date over 20 hexoses transporters, belonging to Sugar Porter family and to Major Facilitator Superfamily, were known. Genome sequence analysis of Candida glabrata, Kluyveromyces lactis, Yarrowia lipolytica, S. cerevisaie and Debaryomyces hansenii reveled potential presence of 17-48 sugar porter proteins. Glucose transporters in S. cerevisiae have been already characterized. In this paper, hexoses transporters, responsible for assimilation of fructose by cells, are presented and compared. Fructose specific transporter are described for yeasts: Zygosaccharomyces rouxii, Zygosaccharomyces bailli, K. lactis, Saccharomyces pastorianus, S. cerevisiae winemaking strain and for fungus Botritys cinerea and human (Glut5p). Among six yeasts transporters, five are fructose specific, acting by facilitated diffusion or proton symport. Yeasts monosaccharides transporter studies allow understanding of sugars uptake and metabolism important aspects, even in higher eukaryotes cells. PMID:25033548

  18. Strong nucleosomes of yeasts.

    PubMed

    Trifonov, Edward N; Tripathi, Vijay

    2016-02-01

    Yeast genome lacks visibly periodic sequences characteristic of strong nucleosomes (SNs) originally discovered in A. thaliana, C. elegans, and H. sapiens. Yet, the sequences with good match to the (RRRRRYYYYY)n consensus of the SNs do show preference to centromere regions of Schizosaccharomyces pombe, Saccharomyces cerevisiae, and Cryptococcus neoformans - property characteristic of SNs of higher eukaryotes. Candida albicans is the first exception detected so far, where their SNs do not have any affinity to the centromeres, nor pericentromeric regions. Three of the four yeast genomes analyzed possess unique repeating centromere-specific SN sequences (C. albicans, again, is an exception). The results firmly indicate that centromeres of plants, animals, and yeasts in general have special chromatin structure, favoring SNs. PMID:25893982

  19. Yeast killer systems.

    PubMed Central

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

    1997-01-01

    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

  20. Identification and inhibitory properties of multifunctional peptides from pea protein hydrolysate.

    PubMed

    Li, Huan; Aluko, Rotimi E

    2010-11-10

    Pea protein isolate was hydrolyzed with alcalase, and the hydrolysate passed through a 1 kDa cutoff ultrafiltration membrane. The permeate was freeze-dried and fractionated on a cationic solid-phase extraction (SPE) column. All fractions were tested for their inhibitory activities against angiotensin-converting enzyme (ACE), renin, and calmodulin-dependent phosphodiesterase 1 (CaMPDE). With the exception of the first eluted fraction, inhibitory properties of the SPE fractions against CaMPDE (but not ACE and renin) were directly related to cationic character (residence time on the column). However, the fraction that eluted with 1% ammonium hydroxide (SPE 1%) had the highest peptide yield and was subsequently fractionated using two consecutive rounds of reversed-phase high-performance liquid chromatography to obtain three peaks with major peptides identified as IR, KF, and EF by ultra performance liquid chromatography-tandem mass spectrometry. The three dipeptides showed weak inhibitory properties toward CaMPDE but strong inhibitions (IC50 values <25 mM) of ACE and renin. In general, the peptides had higher potency against ACE than against renin. It is indicated from our results that these peptides may be used as potential ingredients to formulate multifunctional food products and nutraceuticals. PMID:20929253

  1. Evolutionary history of Ascomyceteous Yeasts

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Yeasts are important for many industrial and biotechnological processes and show remarkable diversity despite morphological similarities. We have sequenced the genomes of 20 ascomyceteous yeasts of taxonomic and industrial importance including members of Saccharomycotina and Taphrinomycotina. A comp...

  2. Red Yeast Rice: An Introduction

    MedlinePlus

    ... preparations of red yeast rice are used in food products in Chinese cuisine, including Peking duck. Others have been sold as dietary supplements to lower blood levels of cholesterol and related lipids. Some red yeast rice products contain substances called ...

  3. Genetics of Yeasts

    NASA Astrophysics Data System (ADS)

    Querol, Amparo; Fernández-Espinar, M. Teresa; Belloch, Carmela

    The use of yeasts in biotechnology processes dates back to ancient days. Before 7000 BC, beer was produced in Sumeria. Wine was made in Assyria in 3500 BC, and ancient Rome had over 250 bakeries, which were making leavened bread by 100 BC. And milk has been made into Kefyr and Koumiss in Asia for many centuries (Demain, Phaff, & Kurtzman, 1999). However, the importance of yeast in the food and beverage industries was only realized about 1860, when their role in food manufacturing became evident.

  4. Improved ethanol production by a xylose-fermenting recombinant yeast strain constructed through a modified genome shuffling method

    PubMed Central

    2012-01-01

    Background Xylose is the second most abundant carbohydrate in the lignocellulosic biomass hydrolysate. The fermentation of xylose is essential for the bioconversion of lignocelluloses to fuels and chemicals. However the wild-type strains of Saccharomyces cerevisiae are unable to utilize xylose. Many efforts have been made to construct recombinant yeast strains to enhance xylose fermentation over the past few decades. Xylose fermentation remains challenging due to the complexity of lignocellulosic biomass hydrolysate. In this study, a modified genome shuffling method was developed to improve xylose fermentation by S. cerevisiae. Recombinant yeast strains were constructed by recursive DNA shuffling with the recombination of entire genome of P. stipitis with that of S. cerevisiae. Results After two rounds of genome shuffling and screening, one potential recombinant yeast strain ScF2 was obtained. It was able to utilize high concentration of xylose (100 g/L to 250 g/L xylose) and produced ethanol. The recombinant yeast ScF2 produced ethanol more rapidly than the naturally occurring xylose-fermenting yeast, P. stipitis, with improved ethanol titre and much more enhanced xylose tolerance. Conclusion The modified genome shuffling method developed in this study was more effective and easier to operate than the traditional protoplast-fusion-based method. Recombinant yeast strain ScF2 obtained in this study was a promising candidate for industrial cellulosic ethanol production. In order to further enhance its xylose fermentation performance, ScF2 needs to be additionally improved by metabolic engineering and directed evolution. PMID:22809265

  5. L-arabinose fermenting yeast

    DOEpatents

    Zhang, Min; Singh, Arjun; Knoshaug, Eric; Franden, Mary Ann; Jarvis, Eric; Suominen, Pirkko

    2010-12-07

    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##

  6. Screening of representative cider yeasts and bacteria for volatile phenol-production ability.

    PubMed

    Buron, Nicolas; Coton, Monika; Desmarais, Ccile; Ledauphin, Jrme; Guichard, Hugues; Barillier, Daniel; Coton, Emmanuel

    2011-10-01

    Representative cider microorganisms (47 yeast strains and 16 bacterial strains) were studied for their ability to produce volatile phenols in a synthetic medium simulating cider conditions and supplemented with the necessary precursors. The various strains were tested for cinnamoyl esterase activity and only Lactobacillus collinoides were able to hydrolyse chlorogenic acid. Phenolic acid decarboxylase (PAD) activities were observed for 6 yeasts and 4 bacterial species allowing them to produce vinylphenols from hydroxycinnamic acids. On the other hand, 4 bacterial species exhibited phenolic acid reductase (PAR) activities leading to the formation of hydroxyphenylpropionic acids. Brettanomyces/Dekkera anomala and L.collinoides were able to produce 4-ethylcatechol (4-EC) and 4-ethylphenol (4-EP) from caffeic and p-coumaric acid, respectively, indicating that both species exhibit PAD and vinylphenol reductase (VPR) activities. In the experimental conditions used, the production of ethylphenols by L.collinoides was faster than the one observed for D.anomala. PMID:21839372

  7. Fast and sensitive detection of genetically modified yeasts in wine.

    PubMed

    León, Carlos; García-Cañas, Virginia; González, Ramón; Morales, Pilar; Cifuentes, Alejandro

    2011-10-21

    In this work, a novel screening methodology based on the combined use of multiplex polymerase chain reaction (PCR) and capillary gel electrophoresis with laser induced fluorescence (CGE-LIF) is developed for the fast and sensitive detection of genetically modified yeasts in wine. As model, a recombinant EKD-13 Saccaromyces cerevisiae strain was selected and different wines were prepared using either recombinant or conventional yeasts. Special emphasis is put on the yeast DNA extraction step, exploring different commercial and non-commercial methods, in order to overcome the important difficulty of obtaining amplifiable DNA from wine samples. To unequivocally detect the transgenic yeast, two specific segments of the transgenic construction were amplified. In addition, a third primer pair was used as amplification control to confirm the quality of the yeast DNA obtained from the extraction step. CGE-LIF provides high sensitivity, good analysis speed and impressive resolution of DNA fragments, making this technique very convenient to optimize multiplex PCR parameters and to analyze the amplified DNA fragments. Thus, the CGE-LIF method provided %RSD values for DNA migration times lower than 0.82% (n=10) with the same capillary and lower than 1.92% (n=15) with three different capillaries, allowing the adequate size determination of the PCR products with an error lower than 4% compared to the theoretically expected. The whole method developed in this work requires less than one working day and grants the sensitive detection of transgenic yeasts in wine samples. PMID:21296357

  8. Engineering Corynebacterium crenatum to produce higher alcohols for biofuel using hydrolysates of duckweed (Landoltia punctata) as feedstock.

    PubMed

    Su, Haifeng; Jiang, Juan; Lu, Qiuli; Zhao, Zhao; Xie, Tian; Zhao, Hai; Wang, Maolin

    2015-01-01

    Early trials have demonstrated great potential for the use of duckweed (family Lemnaceae) as the next generation of energy plants for the production of biofuels. Achieving this technological advance demands research to develop novel bioengineering microorganisms that can ferment duckweed feedstock to produce higher alcohols. In this study, we used relevant genes to transfer five metabolic pathways of isoleucine, leucine and valine from the yeast Saccharomyces cerevisiae into the bioengineered microorganism Corynebacterium crenatum. Experimental results showed that the bioengineered strain was able to produce 1026.61 mg/L of 2-methyl-1-butanol by fermenting glucose, compared to 981.79 mg/L from the acid hydrolysates of duckweed. The highest isobutanol yields achieved were 1264.63 mg/L from glucose and 1154.83 mg/L from duckweed, and the corresponding highest yields of 3-methyl-1-butanol were 748.35 and 684.79 mg/L. Our findings demonstrate the feasibility of using bioengineered C. crenatum as a platform to construct a bacterial strain that is capable of producing higher alcohols. We have also shown the promise of using duckweed as the basis for developing higher alcohols, illustrating that this group of plants represents an ideal fermentation substrate that can be considered the next generation of alternative energy feedstocks. PMID:25889648

  9. Sugarcane bagasse hydrolysis using yeast cellulolytic enzymes.

    PubMed

    Souza, Angelica Cristina de; Carvalho, Fernanda Paula; Silva e Batista, Cristina Ferreira; Schwan, Rosane Freitas; Dias, Disney Ribeiro

    2013-10-28

    Ethanol fuel production from lignocellulosic biomass is emerging as one of the most important technologies for sustainable development. To use this biomass, it is necessary to circumvent the physical and chemical barriers presented by the cohesive combination of the main biomass components, which hinders the hydrolysis of cellulose and hemicellulose into fermentable sugars. This study evaluated the hydrolytic capacity of enzymes produced by yeasts, isolated from the soils of the Brazilian Cerrado biome (savannah) and the Amazon region, on sugarcane bagasse pre-treated with H2SO4. Among the 103 and 214 yeast isolates from the Minas Gerais Cerrado and the Amazon regions, 18 (17.47%) and 11 (5.14%) isolates, respectively, were cellulase-producing. Cryptococcus laurentii was prevalent and produced significant β- glucosidase levels, which were higher than the endo- and exoglucanase activities. In natura sugarcane bagasse was pre-treated with 2% H2SO4 for 30 min at 150oC. Subsequently, the obtained fibrous residue was subjected to hydrolysis using the Cryptococcus laurentii yeast enzyme extract for 72 h. This enzyme extract promoted the conversion of approximately 32% of the cellulose, of which 2.4% was glucose, after the enzymatic hydrolysis reaction, suggesting that C. laurentii is a good β-glucosidase producer. The results presented in this study highlight the importance of isolating microbial strains that produce enzymes of biotechnological interest, given their extensive application in biofuel production. PMID:23851270

  10. Nucleolar and nuclear envelope proteins of the yeast Saccharomyces cerevisiae.

    PubMed

    Hurt, E C; McDowall, A; Schimmang, T

    1988-08-01

    We have developed a fast and reliable purification protocol to obtain yeast nuclei in intact and pure form and in a reasonable yield. The purified nuclei appear homogeneous at the light and electron microscopic level, are highly enriched in the nuclear marker histone H2B and devoid of mitochondrial, vacuolar and cytosolic marker proteins. On sodium dodecyl sulfate (SDS)-polyacrylamide gels, the nuclear fraction contains unique proteins which distinguishes them from the major yeast subcellular fractions. Yeast nuclei were separated by detergent/salt extraction into soluble, insoluble and membrane fractions. Antibodies raised against subnuclear fractions lead to the identification of an integral nuclear membrane protein and a high-abundance 38-kDa protein which is located in the yeast nucleolus. PMID:3053175

  11. Wheat cytosolic acetyl-CoA carboxylase complements an ACC1 null mutation in yeast.

    PubMed

    Joachimiak, M; Tevzadze, G; Podkowinski, J; Haselkorn, R; Gornicki, P

    1997-09-01

    Spores harboring an ACC1 deletion derived from a diploid Saccharomyces cerevisiae strain, in which one copy of the entire ACC1 gene is replaced with a LEU2 cassette, fail to grow. A chimeric gene consisting of the yeast GAL10 promoter, yeast ACC1 leader, wheat cytosolic acetyl-CoA carboxylase (ACCase) cDNA, and yeast ACC1 3' tail was used to complement a yeast ACC1 mutation. The complementation demonstrates that active wheat ACCase can be produced in yeast. At low concentrations of galactose, the activity of the "wheat gene" driven by the GAL10 promoter is low and ACCase becomes limiting for growth, a condition expected to enhance transgenic yeast sensitivity to wheat ACCase-specific inhibitors. An aryloxyphenoxypropionate and two cyclohexanediones do not inhibit growth of haploid yeast strains containing the yeast ACC1 gene, but one cyclohexanedione inhibits growth of the gene-replacement strains at concentrations below 0.2 mM. In vitro, the activity of wheat cytosolic ACCase produced by the gene-replacement yeast strain is inhibited by haloxyfop and cethoxydim at concentrations above 0.02 mM. The activity of yeast ACCase is less affected. The wheat plastid ACCase in wheat germ extract is inhibited by all three herbicides at concentrations below 0.02 mM. Yeast gene-replacement strains will provide a convenient system for the study of plant ACCases. PMID:11038571

  12. Wheat cytosolic acetyl-CoA carboxylase complements an ACC1 null mutation in yeast

    PubMed Central

    Joachimiak, M.; Tevzadze, G.; Podkowinski, J.; Haselkorn, R.; Gornicki, P.

    1997-01-01

    Spores harboring an ACC1 deletion derived from a diploid Saccharomyces cerevisiae strain, in which one copy of the entire ACC1 gene is replaced with a LEU2 cassette, fail to grow. A chimeric gene consisting of the yeast GAL10 promoter, yeast ACC1 leader, wheat cytosolic acetyl-CoA carboxylase (ACCase) cDNA, and yeast ACC1 3′ tail was used to complement a yeast ACC1 mutation. The complementation demonstrates that active wheat ACCase can be produced in yeast. At low concentrations of galactose, the activity of the “wheat gene” driven by the GAL10 promoter is low and ACCase becomes limiting for growth, a condition expected to enhance transgenic yeast sensitivity to wheat ACCase-specific inhibitors. An aryloxyphenoxypropionate and two cyclohexanediones do not inhibit growth of haploid yeast strains containing the yeast ACC1 gene, but one cyclohexanedione inhibits growth of the gene-replacement strains at concentrations below 0.2 mM. In vitro, the activity of wheat cytosolic ACCase produced by the gene-replacement yeast strain is inhibited by haloxyfop and cethoxydim at concentrations above 0.02 mM. The activity of yeast ACCase is less affected. The wheat plastid ACCase in wheat germ extract is inhibited by all three herbicides at concentrations below 0.02 mM. Yeast gene-replacement strains will provide a convenient system for the study of plant ACCases. PMID:11038571

  13. Yeast cells proliferation on various strong static magnetic fields and temperatures

    NASA Astrophysics Data System (ADS)

    Otabe, E. S.; Kuroki, S.; Nikawa, J.; Matsumoto, Y.; Ooba, T.; Kiso, K.; Hayashi, H.

    2009-03-01

    The effect of strong magnetic fields on activities of yeast cells were investigated. Experimental yeast cells were cultured in 5 ml of YPD(Yeast extract Peptone Dextrose) for the number density of yeast cells of 5.0 ±0.2 x 106/ml with various temperatures and magnetic fields up to 10 T. Since the yeast cells were placed in the center of the superconducting magnet, the effect of magnetic force due to the diamagnetism and magnetic gradient was negligibly small. The yeast suspension was opened to air and cultured in shaking condition. The number of yeast cells in the yeast suspension was counted by a counting plate with an optical microscope, and the time dependence of the number density of yeast cells was measured. The time dependence of the number density of yeast cells, ρ, of initial part is analyzed in terms of Malthus equation as given by ρ = ρo exp(kt), where k is the growth coefficient. It is found that, the growth coefficient under the magnetic field is suppressed compared with the control. The growth coefficient decreasing as increasing magnetic field and is saturated at about 5 T. On the other hand, it is found that the suppression of growth of yeast cells by the magnetic field is diminished at high temperatures.

  14. Utilization of hydrolysate from lignocellulosic biomass pretreatment to generate electricity by enzymatic fuel cell system.

    PubMed

    Kim, Sung Bong; Kim, Dong Sup; Yang, Ji Hyun; Lee, Junyoung; Kim, Seung Wook

    2016-04-01

    The waste hydrolysate after dilute acid pretreatment (DAP) of lignocellulosic biomass was utilized to generate electricity using an enzymatic fuel cell (EFC) system. During DAP, the components of biomass containing hemicellulose and other compounds are hydrolyzed, and glucose is solubilized into the dilute acid solution, called as the hydrolysate liquid. Glucose oxidase (GOD) and laccase (Lac) were assembled on the electrode of the anode and cathode, respectively. Cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) were measured, and the maximum power density was found to be 1.254×10(3)μW/cm(2). The results indicate that the hydrolysate from DAP is a reliable electrolyte containing the fuel of EFC. Moreover, the impurities in the hydrolysate such as phenols and furans slightly affected the charge transfer on the surface of the electrode, but did not affect the power generation of the EFC system in principal. PMID:26920478

  15. Pichia anomala 29X: a resistant strain for lignocellulosic biomass hydrolysate fermentation.

    PubMed

    Zha, Ying; Hossain, Abeer H; Tobola, Felix; Sedee, Norbert; Havekes, Mieke; Punt, Peter J

    2013-11-01

    To efficiently use lignocellulosic biomass hydrolysates as fermentation media for bioethanol production, besides being capable of producing significant amount of ethanol, the fermenting host should also meet the following two requirements: (1) resistant to the inhibitory compounds formed during biomass pretreatment process, (2) capable of utilizing C5 sugars, such as xylose, as carbon source. In our laboratory, a screening was conducted on microorganisms collected from environmental sources for their tolerance to hydrolysate inhibitors. A unique resistant strain was selected and identified as Pichia anomala (Wickerhamomyces anomalus), deposited as CBS 132101. The strain is able to produce ethanol in various biomass hydrolysates, both with and without oxygen. Besides, the strain could assimilate xylose and use nitrate as N source. These physiological characteristics make P. anomala an interesting strain for bioethanol production from lignocellulosic biomass hydrolysates. PMID:23826802

  16. Angiotensin I converting enzyme inhibitory peptides purified from bovine skin gelatin hydrolysate.

    PubMed

    Kim, S K; Byun, H G; Park, P J; Shahidi, F

    2001-06-01

    Bovine skin gelatin was hydrolyzed with sequential protease treatments in the order of Alcalase, Pronase E, and collagenase using a three-step ultrafiltration membrane reactor. The molecular weight distributions of the first, second, and third hydrolysates were 4.8-6.6, 3.4-6.6, and 0.9-1.9 kDa, respectively. The angiotensin I converting enzyme (ACE) inhibitory activity of the third hydrolysate (IC(50) = 0.689 mg/mL) was higher than that of the first and second hydrolysates. Two different peptides showing strong ACE inhibitory activity were isolated from the hydrolysate using consecutive chromatographic methods including gel filtration chromatography, ion-exchange chromatography, and reversed-phase high-performance liquid chromatography. The isolated peptides were composed of Gly-Pro-Leu and Gly-Pro-Val and showed IC(50) values of 2.55 and 4.67 microM, respectively. PMID:11409999

  17. Beta-conglycinins among sources of bioactives in soybean hydrolysates that inhibited leukemia cells in vitro

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Soybean is a complex matrix containing several potentially bioactive components. The objective was to build a statistical model to predict the anticancer potential of soybean based on the composition of bioactive components in soybean hydrolysates produced by simulated gastrointestinal digestion. ...

  18. Use of UV absorbance To monitor furans in dilute acid hydrolysates of biomass.

    PubMed

    Martinez, A; Rodriguez, M E; York, S W; Preston, J F; Ingram, L O

    2000-01-01

    A simple method based on UV spectra was developed for the estimation of total furans (furfural and hydroxymethylfurfural) in hemicellulose hydrolysates. UV spectra of hemicellulose hydrolysate contained a single dominant peak at around 278 nm. Approximately two-thirds of this peak can be attributed to furan absorbance (furfural and hydroxymethylfurfural). At 284 nm, both furfural and hydroxymethylfurfural have equal absorbance on a weight basis. A comparison of HPLC determinations for different samples of hydrolysate was used to develop a simple equation that allows the accurate prediction of total furans based on the difference in absorbance at 284 and 320 nm. This method may prove useful for quality control applications during the production of biomass syrups using a dilute acid hydrolysis process and during treatments for the amelioration of toxins. Although furans represent only a portion of the toxins present in hemicellulose hydrolysates, the abundance of furans appears to serve as a useful marker to predict relative toxicity. PMID:10933839

  19. Chemical genomics in yeast

    PubMed Central

    Brenner, Charles

    2004-01-01

    Many drugs have unknown, controversial or multiple mechanisms of action. Four recent 'chemical genomic' studies, using genome-scale collections of yeast gene deletions that were either arrayed or barcoded, have presented complementary approaches to identifying gene-drug and pathway-drug interactions. PMID:15345040

  20. Opportunistic Pathogenic Yeasts

    NASA Astrophysics Data System (ADS)

    Banerjee, Uma

    Advances in medical research, made during the last few decades, have improved the prophylactic, diagnostic and therapeutic capabilities for variety of infections/diseases. However, many of the prophylactic and therapeutic procedures have been seen in many instances to exact a price of host-vulnerability to an expanding group of opportunistic pathogens and yeasts are one of the important members in it. Fortunately amongst the vast majority of yeasts present in nature only few are considered to have the capability to cause infections when certain opportunities predisposes and these are termed as ‘opportunistic pathogenic yeasts.’ However, the term ‘pathogenic’ is quite tricky, as it depends of various factors of the host, the ‘bug’ and the environment to manifest the clinical infection. The borderline is expanding. In the present century with unprecedented increase in number of immune-compromised host in various disciplines of health care settings, where any yeast, which has the capability to grow at 37 ° C (normal body temperature of human), can be pathogenic and cause infection in particular situation

  1. Whey or Casein Hydrolysate with Carbohydrate for Metabolism and Performance in Cycling.

    PubMed

    Oosthuyse, T; Carstens, M; Millen, A M E

    2015-07-01

    The protein type most suitable for ingestion during endurance exercise is undefined. This study compared co-ingestion of either 15 g/h whey or casein hydrolysate with 63 g/h fructose: maltodextrin (0.8:1) on exogenous carbohydrate oxidation, exercise metabolism and performance. 2 h postprandial, 8 male cyclists ingested either: carbohydrate-only, carbohydrate-whey hydrolysate, carbohydrate-casein hydrolysate or placebo-water in a crossover, double-blind design during 2 h of exercise at 60%W max followed by a 16-km time trial. Data were evaluated by magnitude-based inferential statistics. Exogenous carbohydrate oxidation, measured from (13)CO2 breath enrichment, was not substantially influenced by co-ingestion of either protein hydrolysate. However, only co-ingestion of carbohydrate-casein hydrolysate substantially decreased (98% very likely decrease) total carbohydrate oxidation (mean±SD, 242±44; 258±47; 277±33 g for carbohydrate-casein, carbohydrate-whey and carbohydrate-only, respectively) and substantially increased (93% likely increase) total fat oxidation (92±14; 83±27; 73±19 g) compared with carbohydrate-only. Furthermore, only carbohydrate-casein hydrolysate ingestion resulted in a faster time trial (-3.6%; 90% CI: ±3.2%) compared with placebo-water (95% likely benefit). However, neither protein hydrolysate enhanced time trial performance when compared with carbohydrate-only. Under the conditions of this study, ingesting carbohydrate-casein, but not carbohydrate-whey hydrolysate, favourably alters metabolism during prolonged moderate-strenuous cycling without substantially altering cycling performance compared with carbohydrate-only. PMID:25941925

  2. L-arabinose fermenting yeast

    SciTech Connect

    Zhang, Min; Singh, Arjun; Suominen, Pirkko; Knoshaug, Eric; Franden, Mary Ann; Jarvis, Eric

    2013-02-12

    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. A yeast strain engineered to metabolize arabinose through a novel pathway is also disclosed. Methods of producing ethanol include utilizing these modified yeast strains.

  3. L-arabinose fermenting yeast

    SciTech Connect

    Zhang, Min; Singh, Arjun; Suominen, Pirkko; Knoshaug, Eric; Franden, Mary Ann; Jarvis, Eric

    2014-09-23

    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. A yeast strain engineered to metabolize arabinose through a novel pathway is also disclosed. Methods of producing ethanol include utilizing these modified yeast strains.

  4. Label-Free Quantitative Proteomics in Yeast.

    PubMed

    Léger, Thibaut; Garcia, Camille; Videlier, Mathieu; Camadro, Jean-Michel

    2016-01-01

    Label-free bottom-up shotgun MS-based proteomics is an extremely powerful and simple tool to provide high quality quantitative analyses of the yeast proteome with only microgram amounts of total protein. Although the experimental design of this approach is rather straightforward and does not require the modification of growth conditions, proteins or peptides, several factors must be taken into account to benefit fully from the power of this method. Key factors include the choice of an appropriate method for the preparation of protein extracts, careful evaluation of the instrument design and available analytical capabilities, the choice of the quantification method (intensity-based vs. spectral count), and the proper manipulation of the selected quantification algorithm. The elaboration of this robust workflow for data acquisition, processing, and analysis provides unprecedented insight into the dynamics of the yeast proteome. PMID:26483028

  5. Antioxidative activities of hydrolysates from edible birds nest using enzymatic hydrolysis

    NASA Astrophysics Data System (ADS)

    Muhammad, Nurul Nadia; Babji, Abdul Salam; Ayub, Mohd Khan

    2015-09-01

    Edible bird's nest protein hydrolysates (EBN) were prepared via enzymatic hydrolysis to investigate its antioxidant activity. Two types of enzyme (alcalase and papain) were used in this study and EBN had been hydrolysed with different hydrolysis time (30, 60, 90 and 120 min). Antioxidant activities in EBN protein hydrolysate were measured using DPPH, ABTS+ and Reducing Power Assay. From this study, increased hydrolysis time from 30 min to 120 min contributed to higher DH, as shown by alcalase (40.59%) and papain (24.94%). For antioxidant assay, EBN hydrolysed with papain showed higher scavenging activity and reducing power ability compared to alcalase. The highest antioxidant activity for papain was at 120 min hydrolysis time with ABTS (54.245%), DPPH (49.78%) and Reducing Power (0.0680). Meanwhile for alcalase, the highest antioxidant activity was at 30 min hydrolysis time. Even though scavenging activity for EBN protein hydrolysates were high, the reducing power ability was quite low as compared to BHT and ascorbic Acid. This study showed that EBN protein hydrolysate with alcalase and papain treatments potentially exhibit high antioxidant activity which have not been reported before.

  6. Antioxidant properties of carp (Cyprinus carpio L.) protein ex vivo and in vitro hydrolysates.

    PubMed

    Borawska, Justyna; Darewicz, Małgorzata; Vegarud, Gerd E; Minkiewicz, Piotr

    2016-03-01

    The presence of specific peptides with antioxidant properties released during carp protein ex vivo and in vitro hydrolysis by human/porcine digestive enzymes, respectively, was examined. Based on the results of the in silico data analysis, antioxidant peptides were selected for subsequent identification in the digests/hydrolysates. Carp proteins were more resistant to hydrolysis by porcine enzymes than by human digestive juices. The sarcoplasmic proteins were hydrolyzed faster than the myofibrillar ones by both human/porcine enzymes. The in vitro myofibrillar protein hydrolysate showed the highest ABTS(+) scavenging activity (∼232.3 TEAC, μM Trolox/g), whereas the ex vivo hydrolysate of sarcoplasmic proteins showed the highest DPPH scavenging activity (∼88μM/g) and reducing power. Five antioxidant peptides were identified in carp protein ex vivo and in vitro hydrolysates: FIKK, HL, IY, PW, VY. The peptide HL from myofibrillar proteins was identified only in the ex vivo hydrolysate, whereas the peptide PW from sarcoplasmic proteins was identified only in the in vitro hydrolysate. PMID:26471617

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

    PubMed Central

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

    2011-01-01

    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

  8. Antioxidant activity of protein hydrolysates derived from threadfin bream surimi byproducts.

    PubMed

    Wiriyaphan, Chompoonuch; Chitsomboon, Benjamart; Yongsawadigul, Jirawat

    2012-05-01

    Antioxidant activities of protein hydrolysates from threadfin bream surimi wastes, including frame, bone and skin (FBS) and refiner discharge (RD), were investigated. FBS and RD were rich in Lys, Glu, Gly, Pro, Asp, Leu, His, Tyr and Phe. FBS was hydrolysed to a greater extent than RD regardless of proteinases tested (Virgibacillus sp. SK33 proteinase, Alcalase, pepsin and trypsin). Pepsin-hydrolysed FBS, at a 5% degree of hydrolysis (DH), showed the highest antioxidant activity based on 2,2'-azinobis (3-ethyl-benzothiazoline-6-sulphonate) (ABTS) radical (0.455±0.054mg Trolox equivalents/mg leucine equivalents), ferric reducing antioxidant power (FRAP) (0.221±0.005mM Trolox equivalents) and inhibition of β-carotene bleaching assays. FBS hydrolysates showed higher antioxidant activity based on chemical assays than their RD counterparts. However, FBS and RD hydrolysates protected HepG2 cells against tert-butyl hydroperoxide-induced oxidative damage to a similar extent. Therefore, FBS and RD hydrolysates have a potential as antioxidative neutraceutical ingredients. PMID:26434269

  9. Lactic Acid Production from Pretreated Hydrolysates of Corn Stover by a Newly Developed Bacillus coagulans Strain.

    PubMed

    Jiang, Ting; Qiao, Hui; Zheng, Zhaojuan; Chu, Qiulu; Li, Xin; Yong, Qiang; Ouyang, Jia

    2016-01-01

    An inhibitor-tolerance strain, Bacillus coagulans GKN316, was developed through atmospheric and room temperature plasma (ARTP) mutation and evolution experiment in condensed dilute-acid hydrolysate (CDH) of corn stover. The fermentabilities of other hydrolysates with B. coagulans GKN316 and the parental strain B. coagulans NL01 were assessed. When using condensed acid-catalyzed steam-exploded hydrolysate (CASEH), condensed acid-catalyzed liquid hot water hydrolysate (CALH) and condensed acid-catalyzed sulfite hydrolysate (CASH) as substrates, the concentration of lactic acid reached 45.39, 16.83, and 18.71 g/L by B. coagulans GKN316, respectively. But for B. coagulans NL01, only CASEH could be directly fermented to produce 15.47 g/L lactic acid. The individual inhibitory effect of furfural, 5-hydroxymethylfurfural (HMF), vanillin, syringaldehyde and p-hydroxybenzaldehyde (pHBal) on xylose utilization by B. coagulans GKN316 was also studied. The strain B. coagulans GKN316 could effectively convert these toxic inhibitors to the less toxic corresponding alcohols in situ. These results suggested that B. coagulans GKN316 was well suited to production of lactic acid from undetoxified lignocellulosic hydrolysates. PMID:26863012

  10. Lactic Acid Production from Pretreated Hydrolysates of Corn Stover by a Newly Developed Bacillus coagulans Strain

    PubMed Central

    Jiang, Ting; Qiao, Hui; Zheng, Zhaojuan; Chu, Qiulu; Li, Xin; Yong, Qiang; Ouyang, Jia

    2016-01-01

    An inhibitor-tolerance strain, Bacillus coagulans GKN316, was developed through atmospheric and room temperature plasma (ARTP) mutation and evolution experiment in condensed dilute-acid hydrolysate (CDH) of corn stover. The fermentabilities of other hydrolysates with B. coagulans GKN316 and the parental strain B. coagulans NL01 were assessed. When using condensed acid-catalyzed steam-exploded hydrolysate (CASEH), condensed acid-catalyzed liquid hot water hydrolysate (CALH) and condensed acid-catalyzed sulfite hydrolysate (CASH) as substrates, the concentration of lactic acid reached 45.39, 16.83, and 18.71 g/L by B. coagulans GKN316, respectively. But for B. coagulans NL01, only CASEH could be directly fermented to produce 15.47 g/L lactic acid. The individual inhibitory effect of furfural, 5-hydroxymethylfurfural (HMF), vanillin, syringaldehyde and p-hydroxybenzaldehyde (pHBal) on xylose utilization by B. coagulans GKN316 was also studied. The strain B. coagulans GKN316 could effectively convert these toxic inhibitors to the less toxic corresponding alcohols in situ. These results suggested that B. coagulans GKN316 was well suited to production of lactic acid from undetoxified lignocellulosic hydrolysates. PMID:26863012

  11. Continuous co-production of ethanol and xylitol from rice straw hydrolysate in a membrane bioreactor.

    PubMed

    Zahed, Omid; Jouzani, Gholamreza Salehi; Abbasalizadeh, Saeed; Khodaiyan, Faramarz; Tabatabaei, Meisam

    2016-05-01

    The present study was set to develop a robust and economic biorefinery process for continuous co-production of ethanol and xylitol from rice straw in a membrane bioreactor. Acid pretreatment, enzymatic hydrolysis, detoxification, yeast strains selection, single and co-culture batch fermentation, and finally continuous co-fermentation were optimized. The combination of diluted acid pretreatment (3.5 %) and enzymatic conversion (1:10 enzyme (63 floating-point unit (FPU)/mL)/biomass ratio) resulted in the maximum sugar yield (81 % conversion). By concentrating the hydrolysates, sugars level increased by threefold while that of furfural reduced by 50 % (0.56 to 0.28 g/L). Combined application of active carbon and resin led to complete removal of furfural, hydroxyl methyl furfural, and acetic acid. The strains Saccharomyces cerevisiae NCIM 3090 with 66.4 g/L ethanol production and Candida tropicalis NCIM 3119 with 9.9 g/L xylitol production were selected. The maximum concentrations of ethanol and xylitol in the single cultures were recorded at 31.5 g/L (0.42 g/g yield) and 26.5 g/L (0.58 g/g yield), respectively. In the batch co-culture system, the ethanol and xylitol productions were 33.4 g/L (0.44 g/g yield) and 25.1 g/L (0.55 g/g yield), respectively. The maximum ethanol and xylitol volumetric productivity values in the batch co-culture system were 65 and 58 % after 25 and 60 h, but were improved in the continuous co-culture mode and reached 80 % (55 g/L) and 68 % (31 g/L) at the dilution rate of 0.03 L per hour, respectively. Hence, the continuous co-production strategy developed in this study could be recommended for producing value-added products from this hugely generated lignocellulosic waste. PMID:26354791

  12. Contact urticaria from protein hydrolysates in hair conditioners.

    PubMed

    Niinimäki, A; Niinimäki, M; Mäkinen-Kiljunen, S; Hannuksela, M

    1998-11-01

    Protein hydrolysates (PHs) are added to hair-care products (to "repair" broken hair), soaps, bath gels, creams, etc. From one to 22 PHs used in hair-care products (collagen, keratin, elastin, milk, wheat, almond, and silk) were tested in three patient groups: A) 11 hairdressers with hand dermatitis B) 2160 consecutive adults with suspected allergic respiratory disease subjected to routine skin prick tests C) 28 adults with atopic dermatitis. In group A, all the 22 PHs were tested with scratch and patch tests. In groups B and C, one to three PHs were tested with prick tests. Positive scratch/prick test reactions were seen in 12 patients from three PHs altogether. All were women with atopic dermatitis, and all reacted to at least hydroxypropyl trimonium hydrolyzed collagen (Crotein Q). In three patients, prick and open tests with a hair conditioner containing Crotein Q were performed with positive results. One patient reported contact urticaria on her hands, and two reported acute urticaria on their head, face, and upper body from a hair conditioner containing Crotein Q. In seven of the eight studied sera, specific IgE to Crotein Q was detected. In conclusion, PHs of hair cosmetics can cause contact urticaria, especially in patients with atopic dermatitis. PMID:9860241

  13. Improved Functional Characteristics of Whey Protein Hydrolysates in Food Industry.

    PubMed

    Jeewanthi, Renda Kankanamge Chaturika; Lee, Na-Kyoung; Paik, Hyun-Dong

    2015-01-01

    This review focuses on the enhanced functional characteristics of enzymatic hydrolysates of whey proteins (WPHs) in food applications compared to intact whey proteins (WPs). WPs are applied in foods as whey protein concentrates (WPCs), whey protein isolates (WPIs), and WPHs. WPs are byproducts of cheese production, used in a wide range of food applications due to their nutritional validity, functional activities, and cost effectiveness. Enzymatic hydrolysis yields improved functional and nutritional benefits in contrast to heat denaturation or native applications. WPHs improve solubility over a wide range of pH, create viscosity through water binding, and promote cohesion, adhesion, and elasticity. WPHs form stronger but more flexible edible films than WPC or WPI. WPHs enhance emulsification, bind fat, and facilitate whipping, compared to intact WPs. Extensive hydrolyzed WPHs with proper heat applications are the best emulsifiers and addition of polysaccharides improves the emulsification ability of WPHs. Also, WPHs improve the sensorial properties like color, flavor, and texture but impart a bitter taste in case where extensive hydrolysis (degree of hydrolysis greater than 8%). It is important to consider the type of enzyme, hydrolysis conditions, and WPHs production method based on the nature of food application. PMID:26761849

  14. Improved Functional Characteristics of Whey Protein Hydrolysates in Food Industry

    PubMed Central

    Jeewanthi, Renda Kankanamge Chaturika; Lee, Na-Kyoung; Paik, Hyun-Dong

    2015-01-01

    This review focuses on the enhanced functional characteristics of enzymatic hydrolysates of whey proteins (WPHs) in food applications compared to intact whey proteins (WPs). WPs are applied in foods as whey protein concentrates (WPCs), whey protein isolates (WPIs), and WPHs. WPs are byproducts of cheese production, used in a wide range of food applications due to their nutritional validity, functional activities, and cost effectiveness. Enzymatic hydrolysis yields improved functional and nutritional benefits in contrast to heat denaturation or native applications. WPHs improve solubility over a wide range of pH, create viscosity through water binding, and promote cohesion, adhesion, and elasticity. WPHs form stronger but more flexible edible films than WPC or WPI. WPHs enhance emulsification, bind fat, and facilitate whipping, compared to intact WPs. Extensive hydrolyzed WPHs with proper heat applications are the best emulsifiers and addition of polysaccharides improves the emulsification ability of WPHs. Also, WPHs improve the sensorial properties like color, flavor, and texture but impart a bitter taste in case where extensive hydrolysis (degree of hydrolysis greater than 8%). It is important to consider the type of enzyme, hydrolysis conditions, and WPHs production method based on the nature of food application. PMID:26761849

  15. Water Transport in Yeasts.

    PubMed

    Sabir, Farzana; Prista, Catarina; Madeira, Ana; Moura, Teresa; Loureiro-Dias, Maria C; Soveral, Graça

    2016-01-01

    Water moves across membranes through the lipid bilayer and through aquaporins, in this case in a regulated manner. Aquaporins belong to the MIP superfamily and two subfamilies are represented in yeasts: orthodox aquaporins considered to be specific water channels and aquaglyceroporins (heterodox aquaporins). In Saccharomyces cerevisiae genome, four aquaporin isoforms were identified, two of which are genetically close to orthodox aquaporins (ScAqy1 and ScAqy2) and the other two are more closely related to the aquaglyceroporins (ScFps1 and ScAqy3). Advances in the establishment of water channels structure are reviewed in this chapter in relation with the mechanisms of selectivity, conductance and gating. Aquaporins are important for key aspects of yeast physiology. They have been shown to be involved in sporulation, rapid freeze-thaw tolerance, osmo-sensitivity, and modulation of cell surface properties and colony morphology, although the underlying exact mechanisms are still unknown. PMID:26721272

  16. Extracellular Polysaccharides Produced by Yeasts and Yeast-Like Fungi

    NASA Astrophysics Data System (ADS)

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

    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.

  17. [Technology for the whole utilization of brewer's yeast in food industry].

    PubMed

    Otero, M A; Cabello, A; Vasallo, M C; García, L; López, J

    2000-12-01

    A flexible scheme for the fractionation of brewer's yeast was developed. The procedure allows the production of different products such as: dry yeast flakes, dry yeast pills, yeast-extract based table sauce, yeast protein concentrates and soy-like sauce. The investment required for the processing of one ton per day is below 2 million dollars with an overall profitability higher than 53%. Investment is recovered in 0.75 years. The production of food ingredients from yeast upgrades its biomass about 25 fold. Present procedure is compared with other biomass fractionation processes taking into account the utilization of all technological streams where the process becomes environmentally friendly since effluent production significantly lower than similar technologies. PMID:11464667

  18. Immunoprecipitation and Characterization of Membrane Protein Complexes from Yeast

    ERIC Educational Resources Information Center

    Parra-Belky, Karlett; McCulloch, Kathryn; Wick, Nicole; Shircliff, Rebecca; Croft, Nicolas; Margalef, Katrina; Brown, Jamie; Crabill, Todd; Jankord, Ryan; Waldo, Eric

    2005-01-01

    In this undergraduate biochemistry laboratory experiment, the vacuolar ATPase protein complex is purified from yeast cell extracts by doing immunoprecipitations under nondenaturing conditions. Immunoprecipitations are performed using monoclonal antibodies to facilitate data interpretation, and subunits are separated on the basis of their molecular…

  19. Regulation of yeast acetohydroxyacid synthase by valine and ATP.

    PubMed Central

    Pang, S S; Duggleby, R G

    2001-01-01

    The first step in the common pathway for the biosynthesis of branched-chain amino acids is catalysed by acetohydroxyacid synthase (AHAS; EC 4.1.3.18). The enzyme is found in plants, fungi and bacteria, and is regulated by controls on transcription and translation, and by allosteric modulation of catalytic activity. It has long been known that the bacterial enzyme is composed of two types of subunit, and a similar arrangement has been found recently for the yeast and plant enzymes. One type of subunit contains the catalytic machinery, whereas the other has a regulatory function. Previously, we have shown [Pang and Duggleby (1999) Biochemistry 38, 5222--5231] that yeast AHAS can be reconstituted from its separately purified subunits. The reconstituted enzyme is inhibited by valine, and ATP reverses this inhibition. In the present work, we further characterize the structure and the regulatory properties of reconstituted yeast AHAS. High phosphate concentrations are required for reconstitution and it is shown that these conditions are necessary for physical association between the catalytic and regulatory subunits. It is demonstrated by CD spectral changes that ATP binds to the regulatory subunit alone, most probably as MgATP. Neither valine nor MgATP causes dissociation of the regulatory subunit from the catalytic subunit. The specificity of valine inhibition and MgATP activation are examined and it is found that the only effective analogue of either regulator of those tested is the non-hydrolysable ATP mimic, adenosine 5'-[beta,gamma-imido]triphosphate. The kinetics of regulation are studied in detail and it is shown that the activation by MgATP depends on the valine concentration in a complex manner that is consistent with a proposed quantitative model. PMID:11463345

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

    SciTech Connect

    Krishnan, M.S.; Xia, Y.; Ho, N.W.Y.

    1996-10-01

    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.

  1. Yeast Colony Embedding Method

    PubMed Central

    Piccirillo, Sarah; Honigberg, Saul M.

    2011-01-01

    Patterning of different cell types in embryos is a key mechanism in metazoan development. Communities of microorganisms, such as colonies and biofilms also display patterns of cell types. For example, in the yeast S. cerevisiae, sporulated cells and pseudohyphal cells are not uniformly distributed in colonies. The functional importance of patterning and the molecular mechanisms that underlie these patterns are still poorly understood. One challenge with respect to investigating patterns of cell types in fungal colonies is that unlike metazoan tissue, cells in colonies are relatively weakly attached to one another. In particular, fungal colonies do not contain the same extensive level of extracellular matrix found in most tissues . Here we report on a method for embedding and sectioning yeast colonies that reveals the interior patterns of cell types in these colonies. The method can be used to prepare thick sections (0.5 μ) useful for light microscopy and thin sections (0.1 μ) suitable for transmission electron microscopy. Asci and pseudohyphal cells can easily be distinguished from ovoid yeast cells by light microscopy , while the interior structure of these cells can be visualized by EM. The method is based on surrounding colonies with agar, infiltrating them with Spurr's medium, and then sectioning. Colonies with a diameter in the range of 1-2 mm are suitable for this protocol. In addition to visualizing the interior of colonies, the method allows visualization of the region of the colony that invades the underlying agar. PMID:21445054

  2. Models for yeast prions.

    PubMed

    Morgan, B J T; Ridout, M S; Ruddock, L W

    2003-09-01

    The cytoplasmic heritable determinant [PSI+] of the yeast Saccharomyces cerevisiae exhibits prion-like properties. The properties of yeast prions are studied in the hope that this will enhance the understanding of mammalian prions, which cause mad-cow, Creutzfeldt-Jakob, and related neurodegenerative diseases. When host cells divide, the yeast prions distribute themselves without loss over the daughter cells. Experimental data provide information on how the proportion of cells with prions decreases over time when priori replication is inhibited. One feature of scientific interest is the unknown mean number, n0, of prions assumed to be present in the cells at the start of the experiment. We develop several stochastic models and by fitting them to the data, we obtain substantially larger estimates of n0 compared with a previous analysis. An interesting feature of a model with constant cell generation times is that the predicted proportion of cells with prions varies over time as a sequence of linked hyperbolic curves. Avenues for future research are outlined, which relax simplifying assumptions made in the models. We make several recommendations for the design of future experiments. PMID:14601757

  3. Antiproliferative, ACE-inhibitory and functional properties of protein hydrolysates from rohu (Labeo rohita) roe (egg) prepared by gastrointestinal proteases.

    PubMed

    Chalamaiah, M; Jyothirmayi, T; Diwan, Prakash V; Dinesh Kumar, B

    2015-12-01

    Previously, we have reported the chemical composition, molecular mass distribution and antioxidant activity of rohu roe protein hydrolysates. In the current study, antiproliferative, angiotensin-converting enzyme (ACE)-inhibitory activities and functional properties of protein hydrolysates from rohu (Labeo rohita) roe proteins, prepared by gastrointestinal proteases (pepsin and trypsin), were investigated. Antiproliferative activity was evaluated against human colon cancer cell line Caco-2. The results showed that the pepsin hydrolysate possessed dose dependent inhibitory effect on Caco-2 cell line. Pepsin and trypsin hydrolysates displayed ACE-inhibitory activity in vitro. The ACE-inhibitory activity of the hydrolysate generated by pepsin (47 ± 1.7 %, at 1 mg/ml) is higher than that obtained by trypsin (36 ± 3.2 %). Additionally, the undigested rohu roe proteins and its hydrolysates exhibited functional properties. Solubilities of the hydrolysates were above 81 ± 9.2 % at all pH values tested. Pepsin and trypsin hydrolysates showed good foaming capacity (45-211 %) and emulsification activity (4-29 m(2)/g). The foaming abilities and emulsifying activity index (EAI) were affected by pH. The results suggest that protein hydrolysates from rohu roe could be useful in food industry for various applications. PMID:26604407

  4. Production of alcohol from Jerusalem artichokes by yeasts

    SciTech Connect

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

    1982-11-01

    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).

  5. Comparison of Antioxidant Activities of Hydrolysates of Domestic and Imported Skim Milk Powders Treated with Papain.

    PubMed

    Ha, Go Eun; Chang, Oun Ki; Han, Gi Sung; Ham, Jun Sang; Park, Beom-Young; Jeong, Seok-Geun

    2015-01-01

    Milk proteins have many potential sequences within their primary structure, each with a specific biological activity. In this study, we compared and investigated the bioactivities of hydrolysates of the domestic (A, B) and imported (C, D) skim milk powders generated using papain digestion. MALDI-TOF analysis revealed that all milk powder proteins were intact, indicating no autolysis. Electrophoretic analysis of hydrolysates showed papain treatment caused degradation of milk proteins into peptides of various size. The antioxidant activity of the hydrolysates, determined using 2,2-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) and total phenolic contents (TPC) assays, increased with incubation times. In all skim milk powders, the antioxidant activities of hydrolysates were highest following 24 h papain treatment (TPC: A, 196.48 μM GE/L; B, 194.52 μM GE/L; C, 194.76 μM GE/L; D, 163.75 μM GE/L; ABTS: A, 75%; B, 72%; C, 72%; D, 57%). The number of peptide derived from skim milk powders, as determined by LC-MS/MS, was 308 for A, 283 for B, 208 for C, and 135 for D. Hydrolysate A had the highest antioxidant activity and the most potential antioxidant peptides amongst the four skim milk powder hydrolysates. A total of 4 β-lactoglobulin, 4 αs1-casein, and 56 β-casein peptide fragments were identified as potential antioxidant peptides in hydrolysate A by LC-MS/MS. These results suggest that domestic skim milk could have applications in various industries, i.e., in the development of functional foods. PMID:26761850

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

    PubMed Central

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

    2014-01-01

    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

  7. Safety of protein hydrolysates, fractions thereof and bioactive peptides in human nutrition.

    PubMed

    Schaafsma, G

    2009-10-01

    This paper evaluates the safety for humans with regard to consumption of protein hydrolysates and fractions thereof, including bioactive peptides. The available literature on the safety of protein, protein hydrolysates, fractions thereof and free amino acids on relevant food legislation is reviewed and evaluated. A new concept for the safety assessment of protein hydrolysates and fractions thereof is developed. Benchmarks for the evaluation are safety of total protein intake, safety of free amino acid intake, documented history of safe use, outcome of questionnaires in efficacy studies and safety studies. Similar to the intake of intact proteins with a history of safe use, the intake of hydrolysates made from them, does not raise concern about safety, provided the applied proteolytic enzymes are food grade and thus of suitable quality. The safety of hydrolysates and of fractions thereof, including the so-called bioactive peptides, should always be assessed by the company before market introduction (company safety assessment). Only when a novel protein source is used or a novel production process is applied, which results in significant changes in nutritional value, metabolic effect or increased level of undesirable substances, that products might fall under novel food regulations. This means that company safety assessment should be reviewed and approved by external independent experts (external safety evaluation) and the novel protein hydrolysate (fraction) is authorized by competent authorities before market introduction. It is argued that good judgement on the safety of hydrolysates and the fractions thereof can be obtained by comparing the anticipated intake of amino acids by these products with those levels to be reasonably expected to be ingested under normal conditions of consumption of a balanced and varied diet. The paper shows a decision tree that can be used for safety assessment. PMID:19623200

  8. Enzymatic hydrolysis of ovomucoid and the functional properties of its hydrolysates.

    PubMed

    Abeyrathne, E D N S; Lee, H Y; Jo, C; Suh, J W; Ahn, D U

    2015-09-01

    Ovomucoid is well known as a "trypsin inhibitor" and is considered to be the main food allergen in egg. However, the negative functions of ovomucoid can be eliminated if the protein is cut into small peptides. The objectives of this study were to hydrolyze ovomucoid using various enzyme combinations, and compare the functional properties of the hydrolysates. Purified ovomucoid was dissolved in distilled water (20 mg/mL) and treated with 1% of pepsin, α-chymotrypsin, papain, and alcalase, singly or in combinations. Sodium sodium dodecyl sulfate-polyacrylamide (SDS-PAGE) results of the hydrolysates indicated that pepsin (OMP), alcalase (OMAl), alcalase+trypsin (OMAlTr), and alcalase+papain (OMAlPa) treatments best hydrolyzed the ovomucoid, and the 4 treatments were selected to determine their functional characteristics. Among the 4 enzyme treatments, hydrolysate from OMAlTr showed the highest iron-chelating and antioxidant activities, while OMP showed higher ACE-inhibitory activity, but lower Fe-chelating activity than the other treatments. However, no difference in the copper-chelating activity among the treatments was found. MS/MS analysis identified numerous peptides from the hydrolysates of OMAlPa and OMAlTr, and majority of the peptides produced were <2 kDa. Pepsin treatment (OMP), however, hydrolyzed ovomucoid almost completely and produced only amino acid monomers, di- and tri-peptides. The ACE-inhibitory, antioxidant and iron-chelating activities of the enzyme hydrolysates were not consistent with the number and size of peptides in the hydrolysates, but we do not have information about the quantity of each peptide present in the hydrolysates at this point. PMID:26195809

  9. Comparison of Antioxidant Activities of Hydrolysates of Domestic and Imported Skim Milk Powders Treated with Papain

    PubMed Central

    Ha, Go Eun; Chang, Oun Ki; Han, Gi Sung; Ham, Jun Sang; Park, Beom-Young; Jeong, Seok-Geun

    2015-01-01

    Milk proteins have many potential sequences within their primary structure, each with a specific biological activity. In this study, we compared and investigated the bioactivities of hydrolysates of the domestic (A, B) and imported (C, D) skim milk powders generated using papain digestion. MALDI-TOF analysis revealed that all milk powder proteins were intact, indicating no autolysis. Electrophoretic analysis of hydrolysates showed papain treatment caused degradation of milk proteins into peptides of various size. The antioxidant activity of the hydrolysates, determined using 2,2-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) and total phenolic contents (TPC) assays, increased with incubation times. In all skim milk powders, the antioxidant activities of hydrolysates were highest following 24 h papain treatment (TPC: A, 196.48 μM GE/L; B, 194.52 μM GE/L; C, 194.76 μM GE/L; D, 163.75 μM GE/L; ABTS: A, 75%; B, 72%; C, 72%; D, 57%). The number of peptide derived from skim milk powders, as determined by LC-MS/MS, was 308 for A, 283 for B, 208 for C, and 135 for D. Hydrolysate A had the highest antioxidant activity and the most potential antioxidant peptides amongst the four skim milk powder hydrolysates. A total of 4 β-lactoglobulin, 4 αs1-casein, and 56 β-casein peptide fragments were identified as potential antioxidant peptides in hydrolysate A by LC-MS/MS. These results suggest that domestic skim milk could have applications in various industries, i.e., in the development of functional foods. PMID:26761850

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

    PubMed

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

    2014-01-01

    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

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

    NASA Astrophysics Data System (ADS)

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

    1993-09-01

    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.

  12. Peptides released from acid goat whey by a yeast-lactobacillus association isolated from cheese microflora.

    PubMed

    Didelot, Sandrine; Bordenave-Juchereau, Stephanie; Rosenfeld, Eric; Piot, Jean-Marie; Sannier, Frederic

    2006-05-01

    Seven lactobacilli and a variety of microflora extracted from twenty five commercial cheeses were grown on unsupplemented acid goat whey and screened for their capacity to hydrolyse whey proteins [alpha-lactalbumin (alpha-la) and beta-lactoglobulin (beta-lg)] and to generate peptides. Fermentations were performed aerobically or anaerobically at 37 degrees C using crude or pre-heated whey (10 min at 65, 75 or 85 degrees C). Under aerobic conditions, growth of lactobacilli was poor and protein hydrolysis did not occur. Anaerobic conditions slightly increased lactobacilli growth but neither beta-lg hydrolysis nor peptide generation were observed. More than 50% of alpha-la was digested into a truncated form of alpha-la (+/- 12 kDa) in crude whey and whey pre-heated at 65 degrees C. Twenty-five microflora extracted from raw milk cheeses were screened for their proteolytic activities on acid goat whey under the conditions previously described. Eight of them were able to hydrolyse up to 50% of alpha-la mainly during aerobic growth on crude or pre-heated whey. The corresponding hydrolysates were enriched in peptides. The hydrolysate involving microflora extracted from Comté cheese after or at 18 months ripening was the only one to exhibit hydrolysis of both alpha-la and beta-lg. Microbiological analysis showed that microorganisms originating from Comté cheese and capable of growth on unsupplemented whey consisted of Candida parapsilosis and Lactobacillus paracasei. Fermentation kinetic profiles suggested that peptides were released from alpha-la hydrolysis. The co-culture of both microorganisms was required for alpha-la hydrolysis that occurred concomitantly with the pH decrease. During whey fermentation, Cand. parapsilosis excrete at least one protease responsible for alpha-la hydrolysis, and Lb. paracasei is responsible for medium acidification that is required for protease activation. PMID:16476172

  13. 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

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

    2013-01-01

    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

  14. Wood impregnation of yeast lees for winemaking.

    PubMed

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

    2015-03-15

    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

  15. Characteristic and antioxidant activity of retorted gelatin hydrolysates from cobia (Rachycentron canadum) skin.

    PubMed

    Yang, Jing-Iong; Ho, Hsin-Yi; Chu, Yuh-Jwo; Chow, Chau-Jen

    2008-09-01

    Alkali-pretreated cobia (Rachycentron canadum) skin was extracted in a retort (121°C) for 30min to obtain a retorted skin gelatin hydrolysate (RSGH). The molecular mass distributions and antioxidant activities of cobia RSGH and enzyme-treated RSGHs (ET-RSGHs) derived from bromelain, papain, pancreatin, and trypsin digestion were then characterized. The molecular mass distribution of the RSGH ranged mainly between 20,000 and 700Da and those of ET-RSGHs ranged between 6500 and 700Da. The DPPH (α,α-diphenyl-β-picrylhydrazyl) radical scavenging effects (%) of 10mg/ml of RSGH and 10mg/ml of the four ET-RSGHs were 55% and 51-61%, respectively. The lipid peroxidation inhibition (%) of RSGH and ET-RSGHs (10mg/ml) were 58% and 60-71% on the fifth day in a linoleic acid model system, respectively. The 3Kd-ET-RSGHs, obtained by using a series of centrifugal ultrafiltration filters (molecular weight cut-offs of 10, 5, and 3kDa done sequentially with decreasing pore size), exhibited dramatically improved antioxidant activity, with most of the molecular mass ranging below 700Da. Compared to 10mg/ml of the RSGH, 10mg/ml of 3Kd-ET-RSGHs exhibited 45-65% more scavenging of DPPH radical and 24-38% more inhibition of lipid peroxidation. The peptides with molecular masses below 700Da in the ET-RSGHs or 3Kd-ET-RSGHs significantly affect the antioxidant properties. These peptides are composed of a small number of amino acids or free amino acids and have the potential to be added as antioxidants in foods. PMID:26050175

  16. Assessment of Taste Attributes of Peanut Meal Enzymatic-Hydrolysis Hydrolysates Using an Electronic Tongue

    PubMed Central

    Wang, Li; Niu, Qunfeng; Hui, Yanbo; Jin, Huali; Chen, Shengsheng

    2015-01-01

    Peanut meal is the byproduct of high-temperature peanut oil extraction; it is mainly composed of proteins, which have complex tastes after enzymatic hydrolysis to free amino acids and small peptides. The enzymatic hydrolysis method was adopted by using two compound proteases of trypsin and flavorzyme to hydrolyze peanut meal aiming to provide a flavor base. Hence, it is necessary to assess the taste attributes and assign definite taste scores of peanut meal double enzymatic hydrolysis hydrolysates (DEH). Conventionally, sensory analysis is used to assess taste intensity in DEH. However, it has disadvantages because it is expensive and laborious. Hence, in this study, both taste attributes and taste scores of peanut meal DEH were evaluated using an electronic tongue. In this regard, the response characteristics of the electronic tongue to the DEH samples and standard five taste samples were researched to qualitatively assess the taste attributes using PCA and DFA. PLS and RBF neural network (RBFNN) quantitative prediction models were employed to compare predictive abilities and to correlate results obtained from the electronic tongue and sensory analysis, respectively. The results showed that all prediction models had good correlations between the predicted scores from electronic tongue and those obtained from sensory analysis. The PLS and RBFNN prediction models constructed using the voltage response values from the sensors exhibited higher correlation and prediction ability than that of principal components. As compared with the taste performance by PLS model, that of RBFNN models was better. This study exhibits potential advantages and a concise objective taste assessment tool using the electronic tongue in the assessment of DEH taste attributes in the food industry. PMID:25985162

  17. Diversity and Physiological Characterization of D-Xylose-Fermenting Yeasts Isolated from the Brazilian Amazonian Forest

    PubMed Central

    Cadete, Raquel M.; Melo, Monaliza A.; Dussán, Kelly J.; Rodrigues, Rita C. L. B.; Silva, Silvio S.; Zilli, Jerri E.; Vital, Marcos J. S.; Gomes, Fátima C. O.; Lachance, Marc-André; Rosa, Carlos A.

    2012-01-01

    Background This study is the first to investigate the Brazilian Amazonian Forest to identify new D-xylose-fermenting yeasts that might potentially be used in the production of ethanol from sugarcane bagasse hemicellulosic hydrolysates. Methodology/Principal Findings A total of 224 yeast strains were isolated from rotting wood samples collected in two Amazonian forest reserve sites. These samples were cultured in yeast nitrogen base (YNB)-D-xylose or YNB-xylan media. Candida tropicalis, Asterotremella humicola, Candida boidinii and Debaryomyces hansenii were the most frequently isolated yeasts. Among D-xylose-fermenting yeasts, six strains of Spathaspora passalidarum, two of Scheffersomyces stipitis, and representatives of five new species were identified. The new species included Candida amazonensis of the Scheffersomyces clade and Spathaspora sp. 1, Spathaspora sp. 2, Spathaspora sp. 3, and Candida sp. 1 of the Spathaspora clade. In fermentation assays using D-xylose (50 g/L) culture medium, S. passalidarum strains showed the highest ethanol yields (0.31 g/g to 0.37 g/g) and productivities (0.62 g/L·h to 0.75 g/L·h). Candida amazonensis exhibited a virtually complete D-xylose consumption and the highest xylitol yields (0.55 g/g to 0.59 g/g), with concentrations up to 25.2 g/L. The new Spathaspora species produced ethanol and/or xylitol in different concentrations as the main fermentation products. In sugarcane bagasse hemicellulosic fermentation assays, S. stipitis UFMG-XMD-15.2 generated the highest ethanol yield (0.34 g/g) and productivity (0.2 g/L·h), while the new species Spathaspora sp. 1 UFMG-XMD-16.2 and Spathaspora sp. 2 UFMG-XMD-23.2 were very good xylitol producers. Conclusions/Significance This study demonstrates the promise of using new D-xylose-fermenting yeast strains from the Brazilian Amazonian Forest for ethanol or xylitol production from sugarcane bagasse hemicellulosic hydrolysates. PMID:22912807

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

    PubMed Central

    2013-01-01

    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 μg/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

  19. Towards an Understanding of How Protein Hydrolysates Stimulate More Efficient Biosynthesis in Cultured Cells

    NASA Astrophysics Data System (ADS)

    Siemensma, André; Babcock, James; Wilcox, Chris; Huttinga, Hans

    In the light of the growing demand for high quality plant-derived hydrolysates (i.e., HyPep™ and UltraPep™ series), Sheffield Bio-Science has developed a new hydrolysate platform that addresses the need for animal-free cell culture medium supplements while also minimizing variability concerns. The platform is based upon a novel approach to enzymatic digestion and more refined processing. At the heart of the platform is a rationally designed animal component-free (ACF) enzyme cocktail that includes both proteases and non-proteolytic enzymes (hydrolases) whose activities can also liberate primary components of the polymerized non-protein portion of the raw material. This enzyme system is added during a highly optimized process step that targets specific enzyme-substrate reactions to expand the range of beneficial nutritional factors made available to cells in culture. Such factors are fundamental to improving the bio-performance of the culture system, as they provide not merely growth-promoting peptides and amino acids, but also key carbohydrates, lipids, minerals, and vitamins that improve both rate and quality of protein expression, and serve to improve culture life due to osmo-protectant and anti-apoptotic properties. Also of significant note is that, compared to typical hydrolysates, the production process is greatly reduced and requires fewer steps, intrinsically yielding a better-controlled and therefore more reproducible product. Finally, the more sophisticated approach to enzymatic digestion renders hydrolysates more amenable to sterile filtration, allowing hydrolysate end users to experience streamlined media preparation and bioreactor supplementation activities. Current and future development activities will evolve from a better understanding of the complex interactions within a handful of key biochemical pathways that impact the growth and productivity of industrially relevant organisms. Presented in this chapter are some examples of the efforts that have been made so far to elucidate the mechanisms for the often dramatic benefits that hydrolysates can impart on cell culture processes. Given the variety of roles that hydrolysates likely play in each cell type, close collaboration between protein hydrolysate manufacturers and biopharmaceutical developers will continue to be critical to expanding the industry's knowledge and retaining hydrolysates as a tool for enhancing media formulations.

  20. Succinic acid production from duckweed (Landoltia punctata) hydrolysate by batch fermentation of Actinobacillus succinogenes GXAS137.

    PubMed

    Shen, Naikun; Wang, Qingyan; Zhu, Jing; Qin, Yan; Liao, Siming; Li, Yi; Zhu, Qixia; Jin, Yanling; Du, Liqin; Huang, Ribo

    2016-07-01

    Duckweed is potentially an ideal succinic acid (SA) feedstock due to its high proportion of starch and low lignin content. Pretreatment methods, substrate content and nitrogen source were investigated to enhance the bioconversion of duckweed to SA and to reduce the costs of production. Results showed that acid hydrolysis was an effective pretreatment method because of its high SA yield. The optimum substrate concentration was 140g/L. The optimum substrate concentration was 140g/L. Corn steep liquor powder could be considered a feasible and inexpensive alternative to yeast extract as a nitrogen source. Approximately 57.85g/L of SA was produced when batch fermentation was conducted in a 1.3L stirred bioreactor. Therefore, inexpensive duckweed can be a promising feedstock for the economical and efficient production of SA through fermentation by Actinobacillus succinogenes GXAS137. PMID:27023386

  1. Characterisation of hydrolysates prepared from engraved catfish (Nemapteryx caelata) roe by serial hydrolysis.

    PubMed

    Binsi, P K; Viji, P; Panda, Satyen Kumar; Mathew, Suseela; Zynudheen, A A; Ravishankar, C N

    2016-01-01

    Protein hydrolysates were prepared from defatted engraved catfish roe using alcalase enzyme by a two-stage serial hydrolysis process. The soluble hydrolysate formed after first stage of hydrolysis was removed (RH-1) and fresh enzyme was added at the same concentration to achieve further hydrolysis (RH-2). Further, compositional, surface-active and antioxidant properties of both hydrolysates were compared. The SDS-PAGE profile showed two distinct bands for RH-1, whereas no bands were visible for RH-2. On the other hand, gel filtration chromatography of the hydrolysates indicated 3-4 distinct fractions. Both the hydrolysates showed similar foam forming abilities, however, RH-1 exhibited poor foam stability. Emulsion properties of RH-1 were superior to that of RH-2. The major fractions eluted through gel filtration column were screened for antioxidant properties. Higher DPPH radical scavenging and metal chelating properties were observed for RH-1second fragment, whereas FRAP and Fe(2+) reducing power was highest for second fragment of RH-2. PMID:26787939

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

    PubMed

    Ao, Jing; Li, Bo

    2012-10-01

    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

  3. Regulation of Exacerbated Immune Responses in Human Peripheral Blood Cells by Hydrolysed Egg White Proteins

    PubMed Central

    Lozano-Ojalvo, Daniel; Molina, Elena; López-Fandiño, Rosina

    2016-01-01

    The anti-allergic potential of egg white protein hydrolysates (from ovalbumin, lysozyme and ovomucoid) was evaluated as their ability to hinder cytokine and IgE production by Th2-skewed human peripheral blood mononuclear cells (PBMCs), as well as the release of pro-inflammatory factors and generation of reactive oxygen species from Th1-stimulated peripheral blood leukocytes (PBLs). The binding to IgE of egg allergic patients was determined and the peptides present in the hydrolysates were identified. The hydrolysates with alcalase down-regulated the production of Th2-biased cytokines and the secretion of IgE to the culture media of Th2-skewed PBMCs, and they significantly neutralized oxidative stress in PBLs. The hydrolysates of ovalbumin and ovomucoid with pepsin helped to re-establish the Th1/Th2 balance in Th2-biased PBMCs, while they also inhibited the release of pro-inflammatory mediators and reduced oxidative stress in PBLs treated with inflammatory stimuli. The hydrolysates with alcalase, in addition to equilibrating Th2 differentiation, exhibited a low IgE-binding. Therefore, they would elicit mild allergic reactions while retaining T cell-stimulating abilities, which might correlate with an anti-allergic benefit. PMID:27007699

  4. Isolation and characterization of Cupriavidus basilensis HMF14 for biological removal of inhibitors from lignocellulosic hydrolysate

    PubMed Central

    Wierckx, Nick; Koopman, Frank; Bandounas, Luaine; De Winde, Johannes H.; Ruijssenaars, Harald J.

    2010-01-01

    Summary The formation of toxic fermentation inhibitors such as furfural and 5‐hydroxy‐2‐methylfurfural (HMF) during acid (pre‐)treatment of lignocellulose, calls for the efficient removal of these compounds. Lignocellulosic hydrolysates can be efficiently detoxified biologically with microorganisms that specifically metabolize the fermentation inhibitors while preserving the sugars for subsequent use by the fermentation host. The bacterium Cupriavidus basilensis HMF14 was isolated from enrichment cultures with HMF as the sole carbon source and was found to metabolize many of the toxic constituents of lignocellulosic hydrolysate including furfural, HMF, acetate, formate and a host of aromatic compounds. Remarkably, this microorganism does not grow on the most abundant sugars in lignocellulosic hydrolysates: glucose, xylose and arabinose. In addition, C. basilensis HMF14 can produce polyhydroxyalkanoates. Cultivation of C. basilensis HMF14 on wheat straw hydrolysate resulted in the complete removal of furfural, HMF, acetate and formate, leaving the sugar fraction intact. This unique substrate profile makes C. basilensis HMF14 extremely well suited for biological removal of inhibitors from lignocellulosic hydrolysates prior to their use as fermentation feedstock. PMID:21255332

  5. Chickpea protein hydrolysate as a substitute for serum in cell culture

    PubMed Central

    Vioque, Javier; Pedroche, Justo; Alaiz, Manuel; Yust, María M.; Megías, Cristina; Millán, Francisco

    2008-01-01

    The growth of mammalian cells in vitro requires the use of rich culture media that are prepared by combining serum with specific nutrient formulations. Serum, the most expensive component of culture media, provides a complex mixture of growth factors and nutrients. Protein hydrolysates that can support in vitro cell growth and eliminate or reduce the need to use serum have been obtained from different sources. Here we describe the use of two food grade proteases to produce a chickpea protein hydrolysate that has been added to cell culture medium in order to determine whether it can be used as a substitute for serum. Medium containing the hydrolysate has been tested using two human cells lines: the monocytic THP-1 cell line which grows in suspension, and the epithelial Caco-2 cell line which grows as a monolayer. The chickpea protein hydrolysate was a good substitute for serum in the first case, but did not allow growth of Caco-2 cells. Supplementation of culture media with this inexpensive and safe hydrolysate would greatly reduce the cost of cell culture. PMID:19003183

  6. The hypolipidemic effect and antithrombotic activity of Mucuna pruriens protein hydrolysates.

    PubMed

    Herrera Chalé, Francisco; Ruiz Ruiz, Jorge Carlos; Betancur Ancona, David; Acevedo Fernández, Juan José; Segura Campos, Maira Rubi

    2016-01-01

    Hydrolysates and peptide fractions (PF) obtained from M. pruriens protein concentrates with commercial and digestive enzymatic systems were studied for their hypolipidemic and antithrombotic activities. Hydrolysates obtained with Pepsin-Pancreatin (PP) and their peptide fractions inhibited cholesterol micellar solubility with a maximum value of 1.83% in PP. Wistar rats were used to evaluate the hypolipidemic effect of hydrolysates and PF. The higher reductions of cholesterol and triglyceride levels were exhibited by PP and both peptide fractions <1 kDa obtained from PP and Alcalase®-Flavourzyme® hydrolysate (AF) at a dose of 15 mg kg(-1) of animal weight. PF > 10 kDa from both hydrolysates showed the maximum antithrombotic activity with values of 33.33% for PF > 10 kDa from AF and 31.72% for PF > 10 kDa from PP. The results suggest that M. pruriens bioactive peptides with the hypolipidemic effect and antithrombotic activity might be utilized as nutraceuticals. PMID:26505152

  7. The impact of pea protein hydrolysates on bacterial physiological activity--an in vitro study.

    PubMed

    Swiatecka, Dominika; Swiatecki, Aleksander; Kostyra, Henryk; Marciniak-Darmochwał, Katarzyna; Kostyra, Elzbieta

    2010-06-15

    So far, food proteins have been perceived hitherto purely as a source of nutrients indispensable for maintaining life. However, latest findings strongly indicate that food proteins may release biologically active peptides in a consequence of enzymatic degradation. Such hydrolysates may be used as food components in order to beneficially influence human health. Additionally, such modified peptides may affect the balance of bacteria inhabiting human gastrointestinal tract and thus bring about health complication of the host. Although pea seeds are of significant nutritional value due to their high contents of proteins, carbohydrates and fibre, they are also responsible for health inconveniences resulting from their susceptibility to digestion and occurrence of antinutritional as well as allergic compounds. The enzymatic degradation may pass over these nutritional obstacles by liberating hydrolysates empowered not only to exert their impact on the human physiology but also on bacterial intestinal ecosystem. Therefore, the aim of this study was to evaluate the influence of pea protein hydrolysates on bacteria typical for the small intestine. Pea protein hydrolysates have proved to diversely modulate physiological activity of bacteria existing in different states. The observed detrimental effect on planktonic bacteria was abolished in the case of bacteria immobilized to the solid surfaces, confirming the protective effect of biofilms. Additionally, Lactobacilli displayed adaptive properties enabling them to utilize pea protein hydrolysates regardless their state of existence. PMID:20409602

  8. Aggregation properties of whey protein hydrolysates generated with Bacillus licheniformis proteinase activities.

    PubMed

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

    2005-02-23

    Hydrolysis of whey protein concentrate (WPC) with Alcalase 2.4 L, a Bacillus licheniformis proteinase preparation, induces gelation. The aggregation behavior of WPC hydrolysates generated with Alcalase and Prolyve 1000, a Bacillus licheniformis proteinase that did not induce gelation, were studied by turbidity and particle size analysis. With the use of synthetic peptide substrates, it was shown that Alcalase contains a glutamyl endopeptidase (GE) activity not present in Prolyve. Comparison of the aggregation behavior of WPC hydrolysates generated with Alcalase, Prolyve, and combinations of Prolyve with a GE activity isolated from Alcalase showed that GE was responsible for the observed enzyme-induced peptide aggregation in Alcalase hydrolysates. Hydrolysates generated with Prolyve, having a degree of hydrolysis (DH) of 11.8% and 10.4% of peptide material greater than 10 kDa, could be induced to aggregate by the addition of GE. These results emphasize the contribution of enzyme specificity to the physicochemical and functional characteristics of proteinase hydrolysates of WPC. PMID:15713050

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

    PubMed

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

    2014-06-01

    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

  10. Combining treatments to improve the fermentation of sugarcane bagasse hydrolysates by ethanologenic Escherichia coli LY180.

    PubMed

    Geddes, Ryan; Shanmugam, Keelnatham T; Ingram, Lonnie O

    2015-01-01

    Inhibitory side products from dilute acid pretreatment is a major challenge for conversion of lignocellulose into ethanol. Six strategies to detoxify sugarcane hydrolysates were investigated alone, and in combinations (vacuum evaporation of volatiles, high pH treatment with ammonia, laccase, bisulfite, microaeration, and inoculum size). High pH was the most beneficial single treatment, increasing the minimum inhibitory concentration (measured by ethanol production) from 15% (control) to 70% hydrolysate. Combining treatments provided incremental improvements, consistent with different modes of action and multiple inhibitory compounds. Screening toxicity using tube cultures proved to be an excellent predictor of relative performance in pH-controlled fermenters. A combination of treatments (vacuum evaporation, laccase, high pH, bisulfite, microaeration) completely eliminated all inhibitory activity present in hydrolysate. With this combination, fermentation of hemicellulose sugars (90% hydrolysate) to ethanol was complete within 48 h, identical to the fermentation of laboratory xylose (50 g/L) in AM1 mineral salts medium (without hydrolysate). PMID:25864026

  11. Affinity purification of copper-chelating peptides from sunflower protein hydrolysates.

    PubMed

    Megías, Cristina; Pedroche, Justo; Yust, Maria M; Girón-Calle, Julio; Alaiz, Manuel; Millan, Francisco; Vioque, Javier

    2007-08-01

    Copper-chelating peptides were purified from sunflower protein hydrolysates by affinity chromatography using immobilized copper. A variety of protein hydrolysates were obtained by incubation with the proteases Alcalase and Flavourzyme for different periods of time. Chelating activity was indirectly determined by measuring the inhibitory effect of hydrolysates on the oxidation of beta-carotene by copper. Copper-binding peptides purified from the two hydrolysates that inhibited oxidation by copper the most contained 25.4 and 42.0% histidine and inhibited beta-carotene oxidation 8 and 3 times more than the original hydrolysates, which had 2.4 and 2.6% histidine, respectively. Thus, histidine content is not the only factor involved in antioxidant activity, and probably other factors such as peptide size and amino acid sequence are also important. This work shows that affinity chromatography can be used for the purification of copper-chelating peptides and probably other metals of nutritional interest such as calcium, iron, and zinc. In addition to their antioxidant potential, chelating peptides are of nutritional interest because they increase bioavailability of minerals. PMID:17636941

  12. Chickpea protein hydrolysate as a substitute for serum in cell culture.

    PubMed

    Girón-Calle, Julio; Vioque, Javier; Pedroche, Justo; Alaiz, Manuel; Yust, María M; Megías, Cristina; Millán, Francisco

    2008-07-01

    The growth of mammalian cells in vitro requires the use of rich culture media that are prepared by combining serum with specific nutrient formulations. Serum, the most expensive component of culture media, provides a complex mixture of growth factors and nutrients. Protein hydrolysates that can support in vitro cell growth and eliminate or reduce the need to use serum have been obtained from different sources. Here we describe the use of two food grade proteases to produce a chickpea protein hydrolysate that has been added to cell culture medium in order to determine whether it can be used as a substitute for serum. Medium containing the hydrolysate has been tested using two human cells lines: the monocytic THP-1 cell line which grows in suspension, and the epithelial Caco-2 cell line which grows as a monolayer. The chickpea protein hydrolysate was a good substitute for serum in the first case, but did not allow growth of Caco-2 cells. Supplementation of culture media with this inexpensive and safe hydrolysate would greatly reduce the cost of cell culture. PMID:19003183

  13. Whey Protein Concentrate Hydrolysate Prevents Bone Loss in Ovariectomized Rats.

    PubMed

    Kim, Jonggun; Kim, Hyung Kwan; Kim, Saehun; Imm, Ji-Young; Whang, Kwang-Youn

    2015-12-01

    Milk is known as a safe food and contains easily absorbable minerals and proteins, including whey protein, which has demonstrated antiosteoporotic effects on ovariectomized rats. This study evaluated the antiosteoporotic effect of whey protein concentrate hydrolysate (WPCH) digested with fungal protease and whey protein concentrate (WPC). Two experiments were conducted to determine (1) efficacy of WPCH and WPC and (2) dose-dependent impact of WPCH in ovariectomized rats (10 weeks old). In Experiment I, ovariectomized rats (n=45) were allotted into three dietary treatments of 10 g/kg diet of WPC, 10 g/kg diet of WPCH, and a control diet. In Experiment II, ovariectomized rats (n=60) were fed four different diets (0, 10, 20, and 40 g/kg of WPCH). In both experiments, sham-operated rats (n=15) were also fed a control diet containing the same amount of amino acids and minerals as dietary treatments. After 6 weeks, dietary WPCH prevented loss of bone, physical properties, mineral density, and mineral content, and improved breaking strength of femurs, with similar effect to WPC. The bone resorption enzyme activity (tartrate resistance acid phosphatase) in tibia epiphysis decreased in response to WPCH supplementation, while bone formation enzyme activity (alkaline phosphatase) was unaffected by ovariectomy and dietary treatment. Bone properties and strength increased as the dietary WPCH level increased (10 and 20 g/kg), but there was no difference between the 20 and 40 g/kg treatment. WPCH and WPC supplementation ameliorated bone loss induced by ovariectomy in rats. PMID:26367331

  14. Screening for cytotoxic activity of ovotransferrin and its enzyme hydrolysates.

    PubMed

    Moon, S H; Lee, J H; Lee, Y J; Chang, K H; Paik, J Y; Ahn, D U; Paik, H D

    2013-02-01

    The aim of this study was to investigate the cytotoxic activities of ovotransferrin (OTF) from egg white and its enzyme hydrolysates (OTH). The OTF was hydrolyzed at 45°C for 3 h using neutrase, alcalase, acid (0.03 N HCl, pH 2.5), protamex, protex 6L, flavorzyme, α-chymotrypsin, trypsin, and collupulin MG. The enzyme to substrate ratio was 1:25 (wt/wt) in all experiments. Using the 3-(4,5-dimethylthizol-2-yl)-2,5-diphenylatetetrazolium bromide (MTT) assay, the cytotoxicity of OTF and OTH was evaluated in human cancer cell lines of various tissue origins, including the lung (A549 and SK-MES-1), stomach (AGS), breast (MCF-7), larynx (Hep-2), cervix (HeLa), and liver (HepG2). The growth of all cancer cell lines was inhibited by both OTF and OTH in a dose-dependent manner. In particular, OTF displayed relatively high cytotoxicity (≤60% inhibition effects) at 40 mg/mL. At lower concentrations (≤5 mg/mL), however, OTF- and OTH-mediated cytotoxic effects were not significant in all cancer cell lines tested. The MCF-7 cells were the least sensitive to all treatments among all cancer cell lines tested. The OTH-trypsin and OTH-neutrase showed a potent cytotoxicity (over 90% cytotoxicity) to HeLa cells at the 10 mg/mL level. The OTH-trypsin, OTH-protamex, OTH-protex 6L, and OTH-collupulin MG caused 95, 96, 86, and 87% growth inhibition, respectively, in AGS cells. These results indicated there are possibilities that OTF and OTH can be used as natural growth inhibitors of human cancer cell lines. PMID:23300310

  15. Isolation of marine yeasts collected from the Pacific Ocean showing a high production of gamma-aminobutyric acid.

    PubMed

    Masuda, Kazuaki; Guo, Xiao-feng; Uryu, Noboru; Hagiwara, Toshihiko; Watabe, Shugo

    2008-12-01

    Marine yeasts were collected from coastal and deep sea areas in the Pacific Ocean and the Sea of Japan around central and northern Japan to prepare a novel type of natural seasoning. It was found that one of the marine yeasts collected from the Pacific Ocean off Hachinohe showed a high concentration of gamma-aminobutyric acid (GABA) in its extract, about 7-10 times higher than those of commercially available bread yeast and other marine yeasts. The marine yeast isolated and named Hachinohe No. 6 catalyzed the reaction from monosodium glutamate to GABA only in the presence of glucose. Subsequently, several marine yeasts belonging to the genera Pichia and Candida were found to have such catalytic activities, but not those belonging to the genus Saccharomyces. Isolate Hachinohe No. 6 was found to have the highest catalytic activity among the yeasts examined in this study. PMID:19060402

  16. Genomics and the making of yeast biodiversity

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Yeasts are unicellular fungi that do not form fruiting bodies. Although the yeast lifestyle has evolved multiple times, most known species belong to the subphylum Saccharomycotina (syn. Hemiascomycota, hereafter yeasts). This diverse group includes the premier eukaryotic model system, Saccharomyces ...

  17. Biosurfactant-producing yeasts isolated from flowering plants and bees.

    PubMed

    Ianieva, O D

    2013-01-01

    The yeast strains (n=160) have been isolated from various flowering plants and bees Apis mellifera. Oil-spreading method was used to assay the ability of the isolated yeasts to produce biosurfactants. Five most active strains able to synthesize glycolipid biosurfactants produced the oil-spreading zone with diameter 3.66-50 cm The addition of oleic acid, sunflower oil and octadecane significantly increased biosurfactant activity of the studied strains. Crude biosurfactants produced by the strains Candida sp. 79a and 156a were isolated as ethyl acetate extract and proved to be a mixture of glycolipids by thin-layer chromatography. PMID:24006785

  18. Enzymatic hydrolysis of ovomucin and the functional and structural characteristics of peptides in the hydrolysates.

    PubMed

    Abeyrathne, E D N S; Lee, H Y; Jo, C; Suh, J W; Ahn, D U

    2016-02-01

    Ovomucin was hydrolyzed using enzymes or by heating under alkaline conditions (pH 12.0), and the functional, structural and compositional characteristics of the peptides in the hydrolysates were determined. Among the treatments, heating at 100 °C for 15 min under alkaline conditions (OM) produced peptides with the highest iron-binding and antioxidant capacities. Ovomucin hydrolyzed with papain (OMPa) or alcalase (OMAl) produced peptides with high ACE-inhibitory activity. The mass spectrometry analysis indicated that most of the peptides from OMPa were <2 kDa, but peptides from OMTr and OM were >2 kDa. OMAl hydrolyzed ovomucin almost completely and no peptides within 700-5000 Da were found in the hydrolasate. The results indicated that the number and size of peptides were closely related to the functionality of the hydrolysates. Considering the time, cost and activities of the hydrolysates, OM was the best treatment for hydrolyzing ovomucin to produce functional peptides. PMID:26304326

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

    NASA Astrophysics Data System (ADS)

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

    2007-07-01

    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.

  20. Mathematical modeling of hydrolysate diffusion and utilization in cellulolytic biofilms of the extreme thermophile Caldicellulosiruptor obsidiansis

    SciTech Connect

    Wang, Zhiwu; Hamilton-Brehm, Scott; Lochner, Adriane; Elkins, James G; Morrell-Falvey, Jennifer L

    2011-01-01

    Abstract: The morphological and structural properties of microbial biofilms are influenced by internal substrate diffusion and utilization processes. In the case of microbial hydrolysis of plant cell walls, only thin and uniform biofilm structures are typically formed by cellulolytic microorganisms. In this study, we develop a hydrolysate diffusion and utilization model system to examine factors influencing cellulolytic biofilm formation. Model simulations using Caldicellulosiruptor obsidiansis as a representative organism, reveal that the growth of the cellulolytic biofilm is limited by hydrolysate utilization but not diffusion. As a consequence, the cellulolytic biofilm has a uniform growth rate, and there is a hydrolysate surplus that diffuses through the cellulolytic biofilm into the bulk solution where it is consumed by planktonic cells. Predictions based on the model were tested in a cellulose fermentation study and the results are consistent with the model and previously reported experimental data. The factors determining the rate-limiting step of biofilm growth are also analyzed.

  1. Fish protein hydrolysates: proximate composition, amino acid composition, antioxidant activities and applications: a review.

    PubMed

    Chalamaiah, M; Dinesh Kumar, B; Hemalatha, R; Jyothirmayi, T

    2012-12-15

    The fish processing industry produces more than 60% by-products as waste, which includes skin, head, viscera, trimmings, liver, frames, bones, and roes. These by-product wastes contain good amount of protein rich material that are normally processed into low market-value products, such as animal feed, fish meal and fertilizer. In view of utilizing these fish industry wastes, and for increasing the value to several underutilised fish species, protein hydrolysates from fish proteins are being prepared by several researchers all over the world. Fish protein hydrolysates are breakdown products of enzymatic conversion of fish proteins into smaller peptides, which normally contain 2-20 amino acids. In recent years, fish protein hydrolysates have attracted much attention of food biotechnologists due to the availability of large quantities of raw material for the process, and presence of high protein content with good amino acid balance and bioactive peptides (antioxidant, antihypertensive, immunomodulatory and antimicrobial peptides). PMID:22980905

  2. Fermentation of sugars in orange peel hydrolysates to ethanol by recombinant Escherichia coli KO11

    SciTech Connect

    Grohmann, K.; Cameron, R.G.; Buslig, B.S.

    1995-12-31

    The conversion of monosaccharides in orange peel hydrolysates to ethanol by recombinant Escherichia coli KO11 has been investigated in pH-controlled batch fermentations at 32 and 37{degrees}C. pH values and concentration of peel hydrolysate were varied to determine approximate optimal conditions and limitations of these fermentations. Very high yields of ethanol were achieved by this microorganism at reasonable ethanol concentrations (28-48 g/L). The pH range between 5.8 and 6.2 appears to be optimal. The microorganism can convert all major monosaccharides in orange peel hydrolysates to ethanol and to smaller amounts of acetic and lactic acids. Acetic acid is coproduced in equimolar amounts with ethanol by catabolism of salts of galacturonic acid.

  3. Modelling the Yeast Interactome

    PubMed Central

    Janjić, Vuk; Sharan, Roded; Pržulj, Nataša

    2014-01-01

    The topology behind biological interaction networks has been studied for over a decade. Yet, there is no definite agreement on the theoretical models which best describe protein-protein interaction (PPI) networks. Such models are critical to quantifying the significance of any empirical observation regarding those networks. Here, we perform a comprehensive analysis of yeast PPI networks in order to gain insights into their topology and its dependency on interaction-screening technology. We find that: (1) interaction-detection technology has little effect on the topology of PPI networks; (2) topology of these interaction networks differs in organisms with different cellular complexity (human and yeast); (3) clear topological difference is present between PPI networks, their functional sub-modules, and their inter-functional “linkers”; (4) high confidence PPI networks have more “geometrical” topology compared to predicted, incomplete, or noisy PPI networks; and (5) inter-functional “linker” proteins serve as mediators in signal transduction, transport, regulation and organisational cellular processes. PMID:24589662

  4. From yeast genetics to biotechnology.

    PubMed

    Maráz, Anna

    2002-01-01

    Roots of classical yeast genetics go back to the early work of Lindegreen in the 1930s, who studied thallism, sporulation and inheritance of wine yeast strains belonging to S. cerevisiae. Consequent mutation and hybridization of heterothallic S. cerevisae strains resulted in the discovery of life cycle and mating type system, as well as construction of the genetic map. Elaboration of induced mutation and controlled hybridization of yeast strains opened up new possibilities for the genetic analysis of technologically important properties and for the production of improved industrial strains, but a big drawback was the widely different genetic properties of laboratory and industrial yeast strains. Genetic analysis and mapping of industrial strains were generally hindered because of homothallism, poor sporulation and/or low spore viability of brewing and wine yeast strains [1, 2]. In spite of this, there are a few examples of the application of sexual hybridization in the study of genetic control of important technological properties, e.g. sugar utilization, flocculation and flavor production in brewing yeast strains [3] or in the improvement of ethanol producing S. cerevisiae strains [4]. Rare mating and application of karyogamy deficient (kar-) mutants also proved useful in strain improvement [5]. Importance of yeasts in biotechnology is enormous. This includes food and beverage fermentation processes where a wide range of yeast species are playing role, but S. cerevisiae is undoubtedly the most important species among them. New biotechnology is aiming to improve these technologies, but besides this, a completely new area of yeast utilization has been emerged, especially in the pharmaceutical and medical areas. Without decreasing the importance of S. cerevisiae, numerous other yeast species, e.g. Kluyveromyces lactis, Hansenula polymorpha, Pichia pastoris, Schizosaccharomyces pombe and Yarrowia lipolytica have gained increasing potentialities in the modern fermentation biotechnology [6]. Developments in yeast genetics, biochemistry, physiology and process engineering provided bases of rapid development in modern biotechnology, but elaboration of the recombinant DNA technique is far the most important milestone in this field. Other molecular genetic techniques, as molecular genotyping of yeast strains proved also very beneficial in yeast fermentation technologies, because dynamics of both the natural and inoculated yeast biota could be followed by these versatile DNA-based techniques. PMID:12512257

  5. Significant quantities of the glycolytic enzyme phosphoglycerate mutase are present in the cell wall of yeast Saccharomyces cerevisiae.

    PubMed Central

    Motshwene, Precious; Brandt, Wolf; Lindsey, George

    2003-01-01

    NaOH was used to extract proteins from the cell walls of the yeast Saccharomyces cerevisiae. This treatment was shown not to disrupt yeast cells, as NaOH-extracted cells displayed a normal morphology upon electron microscopy. Moreover, extracted and untreated cells had qualitatively similar protein contents upon disruption. When yeast was grown in the presence of 1 M mannitol, two proteins were found to be present at an elevated concentration in the cell wall. These were found to be the late-embryogenic-abundant-like protein heat-shock protein 12 and the glycolytic enzyme phosphoglycerate mutase. The presence of phosphoglycerate mutase in the cell wall was confirmed by immunocytochemical analysis. Not only was the phosphoglycerate mutase in the yeast cell wall found to be active, but whole yeast cells were also able to convert 3-phosphoglycerate in the medium into ethanol, provided that the necessary cofactors were present. PMID:12238949

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

    PubMed

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

    2003-01-01

    The filtrate from steam-pretreated poplar was analyzed to identify degradation compounds. The effect of selected compounds 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, were carried out. The degree of inhibition on yeast strain growth and ethanolic fermentation was determined. At concentrations found in the prehy-drolysate, none of the individual compounds significantly affected the fermentation. For all tested compounds, growth was inhibited to a lesser extent than ethanol production. Lower concentrations of catechol (0.96 g/L) and 4-hydroxybenzaldehyde (1.02 g/L) were required to produce the 50% reduction in cell mass in comparison to other tested compounds. PMID:12721481

  7. Red yeast rice for dysipidemia.

    PubMed

    Shamim, Shariq; Al Badarin, Firas J; DiNicolantonio, James J; Lavie, Carl J; O'Keefe, James H

    2013-01-01

    Red yeast rice is an ancient Chinese food product that contains monacolins, chemical substances that are similar to statins in their mechanisms of action and lipid lowering properties. Several studies have found red yeast rice to be moderately effective at improving the lipid profile, particularly for lowering the low-density lipoprotein cholesterol levels. One large randomized controlled study from China found that red yeast rice significantly improved risk of major adverse cardiovascular events and overall survival in patients following myocardial infarction. Thus, red yeast rice is a potentially useful over-the-counter cholesterol-lowering agent. However, many red yeast rice formulations are non-standardized and unregulated food supplements, and there is a need for further research and regulation of production. PMID:24003656

  8. Rapid Differentiation Between Nocardia and Streptomyces by Paper Chromatography of Whole-Cell Hydrolysates

    PubMed Central

    Becker, B.; Lechevalier, Mary P.; Gordon, Ruth E.; Lechevalier, H. A.

    1964-01-01

    Whole-cell hydrolysates were prepared from 58 strains of nocardiae and streptomycetes. Strains morphologically intermediate between the two genera and morphological variants of the same strains were included. Paper chromatograms made from the whole-cell hydrolysates clearly demonstrated meso-diaminopimelic acid as a major constituent of cultures of Nocardia spp., and LL-diaminopimelic acid as a major constituent of cultures of Streptomyces spp. In cultures of ten strains of N. madurae and of three of N. pelletieri, meso-diaminopimelic acid predominated, thereby supporting the assignment of these species to the genus Nocardia. PMID:14215972

  9. Gelatin hydrolysate from blacktip shark skin prepared using papaya latex enzyme: Antioxidant activity and its potential in model systems.

    PubMed

    Kittiphattanabawon, Phanat; Benjakul, Soottawat; Visessanguan, Wonnop; Shahidi, Fereidoon

    2012-12-01

    Antioxidant activities of gelatin hydrolysates from blacktip shark skin prepared using papaya latex enzyme with different degrees of hydrolysis (DHs: 10%, 20%, 30% and 40%) were evaluated. All antioxidant activity indices of hydrolysates increased with increasing DH (P<0.05). When gelatin hydrolysate with 40%DH was determined for its pH and thermal stability, ORAC and chelating activity remained constant or slightly increased in a wide pH range (1-9) and during heating (100°C) for 240min. It was also stable in simulated gastrointestinal tract model system. Moreover, gelatin hydrolysate at a level of 500 and 1000ppm could inhibit lipid oxidation in both β-carotene linoleate and cooked comminuted pork model systems. Therefore, gelatin hydrolysate from blacktip shark skin (40%DH) can potentially be used as an alternative source of natural antioxidants. PMID:22953833

  10. Production of bioactive peptide hydrolysates from deer, sheep and pig plasma using plant and fungal protease preparations.

    PubMed

    Bah, Clara S F; Bekhit, Alaa El-Din A; Carne, Alan; McConnell, Michelle A

    2015-06-01

    Plasma separated from deer, sheep and pig blood, obtained from abattoirs, was hydrolysed using protease preparations from plant (papain and bromelain) and fungal (FP400 and FPII) sources. Antioxidant and antimicrobial activities of the peptide hydrolysates obtained after 1, 2, 4 and 24h of hydrolysis, were investigated. The release of trichloroacetic acid-soluble peptides over the hydrolysis period was monitored using the o-phthaldialdehyde (OPA) assay, while the hydrolysis profiles were visualised using SDS-PAGE. The major plasma proteins in the animal plasmas were identified using MALDI-TOF-TOF MS. Hydrolysates of plasma generated with fungal proteases exhibited higher DPPH radical-scavenging, oxygen radical-scavenging capacity (ORAC) and ferric reducing antioxidant power (FRAP) than those generated with plant proteases for all three animal plasmas. No antimicrobial activity was detected in the hydrolysates. The results indicated that proteolytic hydrolysis of animal blood plasmas, using fungal protease preparations in particular, produces hydrolysates with high antioxidant properties. PMID:25624206

  11. Pepsin Egg White Hydrolysate Ameliorates Obesity-Related Oxidative Stress, Inflammation and Steatosis in Zucker Fatty Rats.

    PubMed

    Garcés-Rimón, M; González, C; Uranga, J A; López-Miranda, V; López-Fandiño, R; Miguel, M

    2016-01-01

    The aim of this work was to evaluate the effect of the administration of egg white hydrolysates on obesity-related disorders, with a focus on lipid metabolism, inflammation and oxidative stress, in Zucker fatty rats. Obese Zucker rats received water, pepsin egg white hydrolysate (750 mg/kg/day) or Rhizopus aminopeptidase egg white hydrolysate (750 mg/kg/day) for 12 weeks. Lean Zucker rats received water. Body weight, solid and liquid intakes were weekly measured. At the end of the study, urine, faeces, different organs and blood samples were collected. The consumption of egg white hydrolysed with pepsin significantly decreased the epididymal adipose tissue, improved hepatic steatosis, and lowered plasmatic concentration of free fatty acids in the obese animals. It also decreased plasma levels of tumor necrosis factor-alpha and reduced oxidative stress. Pepsin egg white hydrolysate could be used as a tool to improve obesity-related complications. PMID:26985993

  12. Pepsin Egg White Hydrolysate Ameliorates Obesity-Related Oxidative Stress, Inflammation and Steatosis in Zucker Fatty Rats

    PubMed Central

    Garcés-Rimón, M.; González, C.; Uranga, J. A.; López-Miranda, V.; López-Fandiño, R.; Miguel, M.

    2016-01-01

    The aim of this work was to evaluate the effect of the administration of egg white hydrolysates on obesity-related disorders, with a focus on lipid metabolism, inflammation and oxidative stress, in Zucker fatty rats. Obese Zucker rats received water, pepsin egg white hydrolysate (750 mg/kg/day) or Rhizopus aminopeptidase egg white hydrolysate (750 mg/kg/day) for 12 weeks. Lean Zucker rats received water. Body weight, solid and liquid intakes were weekly measured. At the end of the study, urine, faeces, different organs and blood samples were collected. The consumption of egg white hydrolysed with pepsin significantly decreased the epididymal adipose tissue, improved hepatic steatosis, and lowered plasmatic concentration of free fatty acids in the obese animals. It also decreased plasma levels of tumor necrosis factor-alpha and reduced oxidative stress. Pepsin egg white hydrolysate could be used as a tool to improve obesity-related complications. PMID:26985993

  13. Effects of soy protein hydrolysates on maize starch retrogradation studied by IR spectra and ESI-MS analysis.

    PubMed

    Lian, Xijun; Zhu, Wei; Wen, Yan; Li, Lin; Zhao, Xiaoshuang

    2013-08-01

    Starch retrogradation is the main cause of quality deterioration of starch-containing foods during storage. The purpose of this study is to find out whether certain soy protein polypeptide in hydrolysates will retard maize starch retrogradation. The results show that all soy protein hydrolysates retard maize starch retrogradation to a certain extent. The IR spectra of hydrolysates and the blends of hydrolysates and maize starch show that the polypeptides might act with reducing end of maize starch during retrogradation. The results of electrospray ionization-mass spectrometry [ESI-MS] show that the polypeptide (m/z 863) is present in all three hydrolysates remarkedly retarding maize starch retrogradation and its relative abundence is also the highest. So the polypeptide containing seven amino acids probably is the key component to significantly inhibit maize starch retrogradation. PMID:23567290

  14. Isolation and Identification of Yeasts from Wild Flowers Collected around Jangseong Lake in Jeollanam-do, Republic of Korea, and Characterization of the Unrecorded Yeast Bullera coprosmaensis

    PubMed Central

    Han, Sang-Min; Hyun, Se-Hee; Lee, Hyang Burm; Lee, Hye Won; Kim, Ha-Kun

    2015-01-01

    Several types of yeasts were isolated from wild flowers around Jangseong Lake in Jeollanam-do, Republic of Korea and identified by comparing the nucleotide sequences of the PCR amplicons for the D1/D2 variable domain of the 26S ribosomal DNA using Basic Local Alignment Search Tool (BLAST) analysis. In total, 60 strains from 18 species were isolated, and Pseudozyma spp. (27 strains), which included Pseudozyma rugulosa (7 strains) and Pseudozyma aphidis (6 strains), was dominant species. Among the 60 strains, Bullera coprosmaensis JS00600 represented a newly recorded yeast strain in Korea, and its microbiological characteristics were investigated. The yeast cell has an oval-shaped morphology measuring 1.4 × 1.7 µm in size. Bullera coprosmaensis JS00600 is an asporous yeast that exhibits no pseudomycelium formation. It grew well in vitamin-free medium as well as in yeast extract-malt extract broth and yeast extract-peptone-dextrose (YPD) broth, and it is halotolerant growing in 10% NaCl-containing YPD broth. PMID:26539042

  15. Characterization of the Immunogenicity and Allergenicity of Two Cow's Milk Hydrolysates--A Study in Brown Norway Rats.

    PubMed

    Bøgh, K L; Barkholt, V; Madsen, C B

    2015-05-01

    Hypoallergenic infant formulas based on hydrolysed milk proteins are used in the diet for cow's milk allergic infants. For a preclinical evaluation of the immunogenicity and allergenicity of new protein ingredients for such hypoallergenic infant formulas as well as for the investigation of which characteristics of hydrolysates that contribute to allergenicity, in vivo models are valuable tools. In this study, we examine the immunogenicity and allergenicity of two hydrolysates in a Brown Norway (BN) rat model, using i.p. dosing, which allows for the use of small quantities. Intact BLG, hydrolysed BLG and a hydrolysed whey product suitable for use in extensively hydrolysed formulas were thoroughly characterized for protein chemical features and administered to BN rats by i.p. immunization with or without adjuvant. Sera were analysed for specific IgG and IgE for evaluation of sensitizing capacity, immunogenicity and antibody-binding capacity. For evaluation of eliciting capacity a skin test was performed. The study showed that the hydrolysates had no residual allergenicity, lacking the capacity to sensitize and elicit reactions in the BN rats. Dosing with or without adjuvant induced a large difference in immunogenicity. Only antibodies from rats sensitized to intact BLG with adjuvant were able to bind the hydrolysates, and the whey-based hydrolysate only showed immunogenicity when dosed with adjuvant. This study showed that hydrolysates can be evaluated by an i.p. animal model, but that the choice of in vitro tests used for evaluation of antibody responses may greatly influence the result as well as may the use of adjuvant. PMID:25619117

  16. Yeast identification in floral nectar of Mimulus aurantiacus (Invited)

    NASA Astrophysics Data System (ADS)

    Kyauk, C.; Belisle, M.; Fukami, T.

    2009-12-01

    Nectar is such a sugar-rich resource that serves as a natural habitat in which microbes thrive. As a result, yeasts arrive to nectar on the bodies of pollinators such as hummingbirds and bees. Yeasts use the sugar in nectar for their own needs when introduced. This research focuses on the identification of different types of yeast that are found in the nectar of Mimulus aurantiacus (commonly known as sticky monkey-flower). Unopened Mimulus aurantiacus flower buds were tagged at Jasper Ridge and bagged three days later. Floral nectar was then extracted and plated on potato dextrose agar. Colonies on the plates were isolated and DNA was extracted from each sample using QIAGEN DNeasy Plant Mini Kit. The DNA was amplified through PCR and ran through gel electrophoresis. The PCR product was used to clone the nectar samples into an E.coli vector. Finally, a phylogenetic tree was created by BLAST searching sequences in GenBank using the Internal Transcribed Space (ITS) locus. It was found that 18 of the 50 identified species were Candida magnifica, 14 was Candida rancensis, 6 were Crytococcus albidus and there were 3 or less of the following: Starmella bombicola, Candida floricola, Aureobasidium pullulans, Pichia kluyvera, Metschnikowa cibodaserisis, Rhodotorua colostri, and Malassezia globosa. The low diversity of the yeast could have been due to several factors: time of collection, demographics of Jasper Ridge, low variety of pollinators, and sugar concentration of the nectar. The results of this study serve as a necessary first step for a recently started research project on ecological interactions between plants, pollinators, and nectar-living yeast. More generally, this research studies the use of the nectar-living yeast community as a natural microcosm for addressing basic questions about the role of dispersal and competitive and facilitative interactions in ecological succession.

  17. Agriculturally important yeasts: Biological control of field and postharvest diseases using yeast antagonists, and yeasts as pathogens of plants

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Two important agricultural aspects of yeasts, control of plant diseases through application of yeasts as the control agent, and yeasts that are plant pathogens are reviewed. Yeasts as biocontrol organisms are presented first, followed by a discussion of some of the more common plant pathogenic yeas...

  18. Fortified versus incurred residues: extraction of furazolidinone metabolite from prawn.

    PubMed

    Johnston, Lesley; Croft, Meg; Murby, John

    2015-06-01

    Most methods reported in the literature for determination of nitrofuran metabolites use the same extraction and derivatisation conditions to hydrolyse and extract the protein-bound residues from animal tissue. While undertaking certification of reference materials for nitrofuran metabolites in freeze-dried prawn, it was found that these conditions are satisfactory for recovery of spiked residues; however, extraction efficiencies of incurred furazolidinone could be substantially increased by further optimisation of the extraction conditions. The availability of a suitable certified reference material allows laboratories to ensure that their method is optimised for incurred residues. PMID:25862475

  19. Isolation and characterization of a processive DNA helicase from the fission yeast Schizosaccharomyces pombe that translocates in a 5'-to-3' direction.

    PubMed Central

    Lee, C; Seo, Y S

    1998-01-01

    We report here the isolation and characterization of a novel DNA helicase from extracts of the fission yeast Schizosaccharomyces pombe. The enzyme, called DNA helicase II, also contains an intrinsic DNA-dependent ATPase activity. Both the helicase and ATPase activities co-purified with a 63 kDa polypeptide on an SDS/polyacrylamide gel. The protein has a sedimentation coefficient of 4.8 S and a Stokes radius of 36 A (3.6 nm); from these data the native molecular mass was calculated to be 65 kDa. The enzyme translocates in a 5'-to-3' direction with respect to the substrate strand to which it is bound. Unwinding reactions carried out in the presence of increasing enzyme showed a sigmoidal curve, suggesting either co-operative interactions between monomers or multimerization of DNA helicase II in the presence of single-stranded DNA and/or ATP. This enzyme favoured adenosine nucleotides (ATP and dATP) as its energy source, but utilized to limited extents GTP, CTP, dGTP and dCTP. Non-hydrolysable ATP analogues did not support helicase activity. Kinetic analyses showed that the unwinding reaction was rapid, being complete after 50-100 s of incubation. Addition of unlabelled substrates to the helicase reaction after preincubation of the enzyme with substrate did not significantly diminish unwinding. The ATPase activity of DNA helicase II increased proportionally with increasing lengths of single-stranded DNA cofactor. In the presence of circular DNA, ATP hydrolysis continued to increase up to the longest time tested (3 h), whereas it ceased to increase after 5-10 min in the presence of shorter oligonucleotides. The initial rate of ATP hydrolysis during the first 5 min of incubation time was not affected by DNA species used. These data indicate that the enzyme does not dissociate from the single-stranded DNA once it is bound and is therefore highly processive. PMID:9716495

  20. The influence of the extent of enzymatic hydrolysis on antioxidative properties and ACE-inhibitory activities of protein hydrolysates from goby (Zosterisessor ophiocephalus) muscle.

    PubMed

    Nasri, Rim; Jridi, Mourad; Lassoued, Imen; Jemil, Ines; Ben Slama-Ben Salem, Rabeb; Nasri, Moncef; Karra-Châabouni, Maha

    2014-07-01

    Antioxidant properties and angiotensin-converting enzyme (ACE) inhibitory activities of protein hydrolysates from goby (Zosterisessor ophiocephalus) muscle, with different degrees of hydrolysis (DH) from 5 to 25%, prepared by treatment with crude proteases extract from smooth hound intestines, were investigated. Goby protein hydrolysates (GPHs) are rich in Gly and Thr, which accounted for 14.1-15% and 11.6-13.2% of the total amino acids, respectively. The antioxidant activities of GPHs were investigated by using several in vitro assay systems. All GPHs exhibited significant metal chelating activity and DPPH free radical-scavenging activity, and inhibited linoleic acid peroxidation. For the ACE-inhibitory activity, as the DH increased, the activity of GPHs increased. The obtained results revealed that antioxidant and ACE-inhibitory activities of GPHs were influenced by the degree of hydrolysis. A medium degree of enzymatic hydrolysis was appropriate to obtain GPHs with good antioxidant activity, while small peptides were essential to obtain high ACE inhibitory activity. PMID:24764223

  1. Antioxidant and ACE-inhibitory activities of hemp (Cannabis sativa L.) protein hydrolysates produced by the proteases AFP, HT, Pro-G, actinidin and zingibain.

    PubMed

    Teh, Sue-Siang; Bekhit, Alaa El-Din A; Carne, Alan; Birch, John

    2016-07-15

    Hemp protein isolates (HPIs) were hydrolysed by proteases (AFP, HT, ProG, actinidin and zingibain). The enzymatic hydrolysis of HPIs was evaluated through the degree of hydrolysis and SDS-PAGE profiles. The bioactive properties of the resultant hydrolysates (HPHs) were accessed through ORAC, DPPḢ scavenging and ACE-inhibitory activities. The physical properties of the resultant HPHs were evaluated for their particle sizes, zeta potential and surface hydrophobicity. HT had the highest rate of caseinolytic activity at the lowest concentration (0.1mgmL(-1)) compared to other proteases that required concentration of 100mgmL(-1) to achieve their maximum rate of caseinolytic activity. This led to the highest degree of hydrolysis of HPIs by HT in the SDS-PAGE profiles. Among all proteases and substrates, HT resulted in the highest bioactivities (ORAC, DPPḢ scavenging and ACE-inhibitory activities) generated from alkali extracted HPI in the shortest time (2h) compared to the other protease preparations. PMID:26948606

  2. Interaction Between Yeasts and Zinc

    NASA Astrophysics Data System (ADS)

    Nicola, Raffaele De; Walker, Graeme

    Zinc is an essential trace element in biological systems. For example, it acts as a cellular membrane stabiliser, plays a critical role in gene expression and genome modification and activates nearly 300 enzymes, including alcohol dehydrogenase. The present chapter will be focused on the influence of zinc on cell physiology of industrial yeast strains of Saccharomyces cerevisiae, with special regard to the uptake and subsequent utilisation of this metal. Zinc uptake by yeast is metabolism-dependent, with most of the available zinc translocated very quickly into the vacuole. At cell division, zinc is distributed from mother to daughter cells and this effectively lowers the individual cellular zinc concentration, which may become zinc depleted at the onset of the fermentation. Zinc influences yeast fermentative performance and examples will be provided relating to brewing and wine fermentations. Industrial yeasts are subjected to several stresses that may impair fermentation performance. Such stresses may also impact on yeast cell zinc homeostasis. This chapter will discuss the practical implications for the correct management of zinc bioavailability for yeast-based biotechnologies aimed at improving yeast growth, viability, fermentation performance and resistance to environmental stresses

  3. Lager yeast comes of age.

    PubMed

    Wendland, Jürgen

    2014-10-01

    Alcoholic fermentations have accompanied human civilizations throughout our history. Lager yeasts have a several-century-long tradition of providing fresh beer with clean taste. The yeast strains used for lager beer fermentation have long been recognized as hybrids between two Saccharomyces species. We summarize the initial findings on this hybrid nature, the genomics/transcriptomics of lager yeasts, and established targets of strain improvements. Next-generation sequencing has provided fast access to yeast genomes. Its use in population genomics has uncovered many more hybridization events within Saccharomyces species, so that lager yeast hybrids are no longer the exception from the rule. These findings have led us to propose network evolution within Saccharomyces species. This "web of life" recognizes the ability of closely related species to exchange DNA and thus drain from a combined gene pool rather than be limited to a gene pool restricted by speciation. Within the domesticated lager yeasts, two groups, the Saaz and Frohberg groups, can be distinguished based on fermentation characteristics. Recent evidence suggests that these groups share an evolutionary history. We thus propose to refer to the Saaz group as Saccharomyces carlsbergensis and to the Frohberg group as Saccharomyces pastorianus based on their distinct genomes. New insight into the hybrid nature of lager yeast will provide novel directions for future strain improvement. PMID:25084862

  4. Yeasts: From genetics to biotechnology

    SciTech Connect

    Russo, S.; Poli, G.; Siman-Tov, R.B.

    1995-12-31

    Yeasts have been known and used in food and alcoholic fermentations ever since the Neolithic Age. In more recent times, on the basis of their peculiar features and history, yeasts have become very important experimental models in both microbiological and genetic research, as well as the main characters in many fermentative production processes. In the last 40 years, advances in molecular biology and genetic engineering have made possible not only the genetic selection of organisms, but also the genetic modification of some of them, especially the simplest of them, such as bacteria and yeasts. These discoveries have led to the availability of new yeast strains fit to fulfill requests of industrial production and fermentation. Moreover, genetically modified and transformed yeasts have been constructed that are able to produce large amounts of biologically active proteins and enzymes. Thus, recombinant yeasts make it easier to produce drugs, biologically active products, diagnostics, and vaccines, by inexpensive and relatively simple techniques. Yeasts are going to become more and more important in the {open_quotes}biotechnological revolution{close_quotes} by virtue of both their features and their very long and safe use in human nutrition and industry. 175 refs., 4 figs., 6 tabs.

  5. Lager Yeast Comes of Age

    PubMed Central

    2014-01-01

    Alcoholic fermentations have accompanied human civilizations throughout our history. Lager yeasts have a several-century-long tradition of providing fresh beer with clean taste. The yeast strains used for lager beer fermentation have long been recognized as hybrids between two Saccharomyces species. We summarize the initial findings on this hybrid nature, the genomics/transcriptomics of lager yeasts, and established targets of strain improvements. Next-generation sequencing has provided fast access to yeast genomes. Its use in population genomics has uncovered many more hybridization events within Saccharomyces species, so that lager yeast hybrids are no longer the exception from the rule. These findings have led us to propose network evolution within Saccharomyces species. This “web of life” recognizes the ability of closely related species to exchange DNA and thus drain from a combined gene pool rather than be limited to a gene pool restricted by speciation. Within the domesticated lager yeasts, two groups, the Saaz and Frohberg groups, can be distinguished based on fermentation characteristics. Recent evidence suggests that these groups share an evolutionary history. We thus propose to refer to the Saaz group as Saccharomyces carlsbergensis and to the Frohberg group as Saccharomyces pastorianus based on their distinct genomes. New insight into the hybrid nature of lager yeast will provide novel directions for future strain improvement. PMID:25084862

  6. Yeasts: from genetics to biotechnology.

    PubMed

    Russo, S; Berkovitz Siman-Tov, R; Poli, G

    1995-01-01

    Yeasts have been known and used in food and alcoholic fermentations ever since the Neolithic Age. In more recent times, on the basis of their peculiar features and history, yeasts have become very important experimental models in both microbiological and genetic research, as well as the main characters in many fermentative production processes. In the last 40 years, advances in molecular biology and genetic engineering have made possible not only the genetic selection of organisms, but also the genetic modification of some of them, especially the simplest of them, such as bacteria and yeasts. These discoveries have led to the availability of new yeast strains fit to fulfill requests of industrial production and fermentation. Moreover, genetically modified and transformed yeasts have been constructed that are able to produce large amounts of biologically active proteins and enzymes. Thus, recombinant yeasts make it easier to produce drugs, biologically active products, diagnostics, and vaccines, by inexpensive and relatively simple techniques. Yeasts are going to become more and more important in the "biotechnological revolution" by virtue of both their features and their very long and safe use in human nutrition and industry. PMID:9003692

  7. Exceptional hexose-fermenting ability of the xylitol-producing yeast Candida guilliermondii FTI 20037.

    PubMed

    Wen, Xin; Sidhu, Sukhdeep; Horemans, Spencer K C; Sooksawat, Najjapak; Harner, Nicole K; Bajwa, Paramjit K; Yuan, Zhirun; Lee, Hung

    2016-06-01

    The yeast Candida guilliermondii FTI 20037 is well-known for its ability to produce xylitol from xylose. Recently, this strain was found to produce greater than 5% (w/v) ethanol from glucose. This level of ethanol is typically not exceeded by wild-type strains of other native pentose-fermenting yeasts. This prompted the current study to examine the ability of C. guilliermondii FTI 20037 to utilize and ferment high concentrations of each of the hexoses commonly found in lignocellulosic hydrolysates. In defined media, FTI 20037 fermented 14.4%-25.9% (w/v) of glucose, mannose or galactose individually to ethanol in concentrations ranging from 6% to 9.3% (w/v). Fermentation was completed within 36 h (for glucose) to 100 h (for galactose). In 25.9% (w/v) glucose, FTI 20037 produced 9.3% (w/v) ethanol within 40 h. FTI 20037 produced xylitol exclusively when xylose was given as the sole carbon source. The strain utilized arabinose poorly. Under the same fermentation conditions, an industrial Saccharomyces cerevisiae strain produced slightly higher levels of ethanol [9.9% (w/v)] from 25.0% (w/v) glucose. Another pentose-fermenting yeast Pachysolen tannophilus also fermented high concentrations of glucose and mannose to produce relatively high peak ethanol concentrations; however, this yeast required considerably longer to completely consume these hexoses. The ability of FTI 20037 to produce high level of ethanol rapidly from glucose is remarkable. To our knowledge, this is the first known instance of a non-modified native xylose-fermenting yeast strain able to produce such high levels of ethanol from glucose as rapidly as S. cerevisiae in a defined medium. PMID:26596373

  8. 21 CFR 172.896 - Dried yeasts.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Dried yeasts. 172.896 Section 172.896 Food and... 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 total folic...

  9. 21 CFR 172.896 - Dried yeasts.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Dried yeasts. 172.896 Section 172.896 Food and... 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 total folic...

  10. 21 CFR 172.896 - Dried yeasts.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Dried yeasts. 172.896 Section 172.896 Food and... PERMITTED FOR DIRECT ADDITION TO FOOD FOR HUMAN CONSUMPTION Multipurpose Additives § 172.896 Dried yeasts. Dried yeast (Saccharomyces cerevisiae and Saccharomyces fragilis) and dried torula yeast (Candida...

  11. 21 CFR 172.896 - Dried yeasts.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Dried yeasts. 172.896 Section 172.896 Food and... 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 total folic...

  12. 21 CFR 172.896 - Dried yeasts.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Dried yeasts. 172.896 Section 172.896 Food and... 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 total folic...

  13. Cryptococcus mujuensis sp. nov. and Cryptococcus cuniculi sp. nov., basidiomycetous yeasts isolated from wild rabbit faeces.

    PubMed

    Shin, Kee-Sun; Oh, Hee-Mock; Park, Yong-Ha; Lee, Kang Hyun; Poo, Haryoung; Kwon, Gi-Seok; Kwon, O-Yu

    2006-09-01

    Two previously undescribed anamorphic yeasts, strains T-11(T) and T-26(T), recovered from wild rabbit faecal pellets collected in Muju, Korea, were identified using phenotypic and molecular taxonomic methods. The isolates were characterized by the proliferation of budding cells, positive diazonium blue B and urease reactions, the presence of Q-10 as the major ubiquinone, the presence of xylose in whole-cell hydrolysates and the inability to ferment sugars. Phylogenetic analyses based on 26S rRNA gene partial sequences revealed that strain T-11(T) was located in the Bulleromyces clade and was related to Sirobasidium intermedium, Tremella exigua, Cryptococcus cellulolyticus and Bullera pseudoalba. Strain T-26(T) was located in the Mesenterica clade and was closely related to Cryptococcus sp. F6 and Cryptococcus heveanensis CBS 8976. Sequence divergence values of more than 4 % from other described Cryptococcus species, together with the phenotypic differences, showed that the isolated yeasts represent previously unrecognized members of this genus. Therefore, two novel yeast species are proposed: Cryptococcus mujuensis sp. nov., with strain T-11(T) (=KCTC 17231(T)=CBS 10308(T)) as the type strain, and Cryptococcus cuniculi sp. nov., with strain T-26(T) (=KCTC 17232(T)=CBS 10309(T)) as the type strain. PMID:16957128

  14. Molybdate induces thermotolerance in yeast.

    PubMed

    Tiligada, E; Miligkos, V; Ypsilantis, E; Papamichael, K; Delitheos, A

    1999-08-01

    Application of a mild heat pretreatment, performed by shifting cells from 27 degrees C to 37 degrees C led to the protection of yeast cells from death due to a subsequent extreme heat shock at 53 degrees C. The presence of cycloheximide inhibited this induction of thermotolerance, indicating the involvement of de novo protein. The phosphatase inhibitor sodium molybdate induced thermotolerance to the non-pretreated yeast cells. This induction of thermotolerance did not seem to depend upon de novo protein synthesis. Thus, acquisition of thermotolerance in yeast may involve a number of cellular mechanisms depending on the conditions the organism encounters at any particular time. PMID:10499293

  15. Triacylglycerol Homeostasis: Insights from Yeast*

    PubMed Central

    Kohlwein, Sepp D.

    2010-01-01

    The endemic increase in lipid-associated disorders such as obesity and type 2 diabetes mellitus has placed triacylglycerol metabolism and its associated organelle, lipid droplets, in the spotlight of biomedical research. Key enzymes of triacylglycerol metabolism are structurally and functionally conserved between yeast and mammalian cells, and studies in yeast have contributed significantly to the understanding of their biological function(s). Based on these similarities, studies performed in yeast may provide further significant mechanistic insight into the molecular basis of triacylglycerol homeostasis and its important physiological roles in healthy and diseased cells. PMID:20231294

  16. Radical scavenging and amino acid profiling of wedge clam, Donax cuneatus (Linnaeus) protein hydrolysates.

    PubMed

    Nazeer, R A; Saranya, M A V; Naqash, Shabeena Yousuf

    2014-12-01

    Body, foot and viscera of Donax cuneatus (Linnaeus) were hydrolyzed using commercial proteases (pepsin, trypsin and papain) and tested for their antioxidant activity by DPPH scavenging ability and reducing power assays. In comparison between all the hydrolysates, papain viscera (28.513 ± 0.165 & 0.186 ± 0.008) and foot (33.567 ± 0.132 & 0.166 ± 0.013) hydrolysates showed highest DPPH and reducing power ability respectively. The active hydrolysates were purified with DEAE- cellulose followed by Sephadex G-25 columns connected to FPLC. Further, the isolated active fractions were loaded onto HPLC for their amino acid profiling and found with the presence of potential amino acids viz., histidine, cysteine, alanine etc. These results suggest that the isolated antioxidant peptide from viscera and foot hydrolysate of D. cuneatus can be used in treating human diseases where free radicals and oxidative damage are involved. PMID:25477664

  17. Characterization of peptides found in unprocessed and extruded amaranth (Amaranthus hypochondriacus) pepsin/pancreatin hydrolysates.

    PubMed

    Montoya-Rodríguez, Alvaro; Milán-Carrillo, Jorge; Reyes-Moreno, Cuauhtémoc; González de Mejía, Elvira

    2015-01-01

    The objectives of this study were to characterize peptides found in unprocessed amaranth hydrolysates (UAH) and extruded amaranth hydrolysates (EAH) and to determine the effect of the hydrolysis time on the profile of peptides produced. Amaranth grain was extruded in a single screw extruder at 125 °C of extrusion temperature and 130 rpm of screw speed. Unprocessed and extruded amaranth flour were hydrolyzed with pepsin/pancreatin enzymes following a kinetic at 10, 25, 60, 90, 120 and 180 min for each enzyme. After 180 min of pepsin hydrolysis, aliquots were taken at each time during pancreatin hydrolysis to characterize the hydrolysates by MALDI-TOF/MS-MS. Molecular masses (MM) (527, 567, 802, 984, 1295, 1545, 2034 and 2064 Da) of peptides appeared consistently during hydrolysis, showing high intensity at 10 min (2064 Da), 120 min (802 Da) and 180 min (567 Da) in UAH. EAH showed high intensity at 10 min (2034 Da) and 120 min (984, 1295 and 1545 Da). Extrusion produced more peptides with MM lower than 1000 Da immediately after 10 min of hydrolysis. Hydrolysis time impacted on the peptide profile, as longer the time lower the MM in both amaranth hydrolysates. Sequences obtained were analyzed for their biological activity at BIOPEP, showing important inhibitory activities related to chronic diseases. These peptides could be used as a food ingredient/supplement in a healthy diet to prevent the risk to develop chronic diseases. PMID:25894223

  18. Characterization of Peptides Found in Unprocessed and Extruded Amaranth (Amaranthus hypochondriacus) Pepsin/Pancreatin Hydrolysates

    PubMed Central

    Montoya-Rodríguez, Alvaro; Milán-Carrillo, Jorge; Reyes-Moreno, Cuauhtémoc; González de Mejía, Elvira

    2015-01-01

    The objectives of this study were to characterize peptides found in unprocessed amaranth hydrolysates (UAH) and extruded amaranth hydrolysates (EAH) and to determine the effect of the hydrolysis time on the profile of peptides produced. Amaranth grain was extruded in a single screw extruder at 125 °C of extrusion temperature and 130 rpm of screw speed. Unprocessed and extruded amaranth flour were hydrolyzed with pepsin/pancreatin enzymes following a kinetic at 10, 25, 60, 90, 120 and 180 min for each enzyme. After 180 min of pepsin hydrolysis, aliquots were taken at each time during pancreatin hydrolysis to characterize the hydrolysates by MALDI-TOF/MS-MS. Molecular masses (MM) (527, 567, 802, 984, 1295, 1545, 2034 and 2064 Da) of peptides appeared consistently during hydrolysis, showing high intensity at 10 min (2064 Da), 120 min (802 Da) and 180 min (567 Da) in UAH. EAH showed high intensity at 10 min (2034 Da) and 120 min (984, 1295 and 1545 Da). Extrusion produced more peptides with MM lower than 1000 Da immediately after 10 min of hydrolysis. Hydrolysis time impacted on the peptide profile, as longer the time lower the MM in both amaranth hydrolysates. Sequences obtained were analyzed for their biological activity at BIOPEP, showing important inhibitory activities related to chronic diseases. These peptides could be used as a food ingredient/supplement in a healthy diet to prevent the risk to develop chronic diseases. PMID:25894223

  19. Soybean and casein hydrolysates induce grapevine immune responses and resistance against Plasmopara viticola.

    PubMed

    Lachhab, Nihed; Sanzani, Simona M; Adrian, Marielle; Chiltz, Annick; Balacey, Suzanne; Boselli, Maurizio; Ippolito, Antonio; Poinssot, Benoit

    2014-01-01

    Plasmopara viticola, the causal agent of grapevine downy mildew, is one of the most devastating grape pathogen in Europe and North America. Although phytochemicals are used to control pathogen infections, the appearance of resistant strains and the concern for possible adverse effects on environment and human health are increasing the search for alternative strategies. In the present investigation, we successfully tested two protein hydrolysates from soybean (soy) and casein (cas) to trigger grapevine resistance against P. viticola. On Vitis vinifera cv. Marselan plants, the application of soy and cas reduced the infected leaf surface by 76 and 63%, as compared to the control, respectively. Since both hydrolysates might trigger the plant immunity, we investigated their ability to elicit grapevine defense responses. On grapevine cell suspensions, a different free cytosolic calcium signature was recorded for each hydrolysate, whereas a similar transient phosphorylation of two MAP kinases of 45 and 49 kDa was observed. These signaling events were followed by transcriptome reprogramming, including the up-regulation of defense genes encoding pathogenesis-related (PR) proteins and the stilbene synthase enzyme responsible for the biosynthesis of resveratrol, the main grapevine phytoalexin. Liquid chromatography analyses confirmed the production of resveratrol and its dimer metabolites, δ- and ε-viniferins. Overall, soy effects were more pronounced as compared to the cas ones. Both hydrolysates proved to act as elicitors to enhance grapevine immunity against pathogen attack. PMID:25566290

  20. Soybean and casein hydrolysates induce grapevine immune responses and resistance against Plasmopara viticola

    PubMed Central

    Lachhab, Nihed; Sanzani, Simona M.; Adrian, Marielle; Chiltz, Annick; Balacey, Suzanne; Boselli, Maurizio; Ippolito, Antonio; Poinssot, Benoit

    2014-01-01

    Plasmopara viticola, the causal agent of grapevine downy mildew, is one of the most devastating grape pathogen in Europe and North America. Although phytochemicals are used to control pathogen infections, the appearance of resistant strains and the concern for possible adverse effects on environment and human health are increasing the search for alternative strategies. In the present investigation, we successfully tested two protein hydrolysates from soybean (soy) and casein (cas) to trigger grapevine resistance against P. viticola. On Vitis vinifera cv. Marselan plants, the application of soy and cas reduced the infected leaf surface by 76 and 63%, as compared to the control, respectively. Since both hydrolysates might trigger the plant immunity, we investigated their ability to elicit grapevine defense responses. On grapevine cell suspensions, a different free cytosolic calcium signature was recorded for each hydrolysate, whereas a similar transient phosphorylation of two MAP kinases of 45 and 49 kDa was observed. These signaling events were followed by transcriptome reprogramming, including the up-regulation of defense genes encoding pathogenesis-related (PR) proteins and the stilbene synthase enzyme responsible for the biosynthesis of resveratrol, the main grapevine phytoalexin. Liquid chromatography analyses confirmed the production of resveratrol and its dimer metabolites, δ- and ε-viniferins. Overall, soy effects were more pronounced as compared to the cas ones. Both hydrolysates proved to act as elicitors to enhance grapevine immunity against pathogen attack. PMID:25566290