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Sample records for active dry yeast

  1. Antioxidant defense parameters as predictive biomarkers for fermentative capacity of active dried wine yeast.

    Science.gov (United States)

    Gamero-Sandemetrio, Esther; Gómez-Pastor, Rocío; Matallana, Emilia

    2014-08-01

    The production of active dried yeast (ADY) is a common practice in industry for the maintenance of yeast starters and as a means of long term storage. The process, however, causes multiple cell injuries, with oxidative damage being one of the most important stresses. Consequentially, dehydration tolerance is a highly appreciated property in yeast for ADY production. In this study we analyzed the cellular redox environment in three Saccharomyces cerevisiae wine strains, which show markedly different fermentative capacities after dehydration. To measure/quantify the effect of dehydration on the S. cerevisiae strains, we used: (i) fluorescent probes; (ii) antioxidant enzyme activities; (ii) intracellular damage; (iii) antioxidant metabolites; and (iv) gene expression, to select a minimal set of biochemical parameters capable of predicting desiccation tolerance in wine yeasts. Our results show that naturally enhanced antioxidant defenses prevent oxidative damage after wine yeast biomass dehydration and improve fermentative capacity. Based on these results we chose four easily assayable parameters/biomarkers for the selection of industrial yeast strains of interest for ADY production: trehalose and glutathione levels, and glutathione reductase and catalase enzymatic activities. Yeast strains selected in accordance with this process display high levels of trehalose, low levels of oxidized glutathione, a high induction of glutathione reductase activity, as well as a high basal level and sufficient induction of catalase activity, which are properties inherent in superior ADY strains. Copyright © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. Antifungal activity evaluation of Aloe arborescens dry extract against trichosporon genus yeasts

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    João Ricardo Bueno de Morais Borba

    2014-10-01

    Full Text Available The objective of this study was to investigate the antifungal activity of Aloe arborescens dry extract against Trichosporon genus yeast species. Extraction was carried out by means of a longitudinal incision in fresh leaves, which were collected on a vat, and the total volume was frozen and subsequently lyophilized. Then, 40 mg of the dry extract was dissolved in DMSO by gentle inversion in order to obtain a solution whose concentration was 4000 µg mL-1. This solution became limpid and slightly yellowish because the pigment of the latex was attenuated. It was performed serial dilutions from 2,000 to 15.625 µg mL-1 with RPMI-1640 broth. There was already no pigment in the first dilution of 2000 μg mL-1. It was analyzed fifteen strains of Trichosporon spp., and Candida albicans ATCC 10231 was used as control strain. We carried out the reading of microplates in the ELISA reader device at a wavelength of 530 nm, after incubation for 24 and 48 hours, and it was determinated the Minimum Inhibitory Concentration (MIC. The MIC50 value obtained for all Trichosporon species and for C. albicans was 500 µg mL-1. As a result, we concluded that Aloe arborescens dry extract has antifungal activity against Trichosporon yeasts.

  3. Construction of novel Saccharomyces cerevisiae strains for bioethanol active dry yeast (ADY) production.

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    Zheng, Daoqiong; Zhang, Ke; Gao, Kehui; Liu, Zewei; Zhang, Xing; Li, Ou; Sun, Jianguo; Zhang, Xiaoyang; Du, Fengguang; Sun, Peiyong; Qu, Aimin; Wu, Xuechang

    2013-01-01

    The application of active dry yeast (ADY) in bioethanol production simplifies operation processes and reduces the risk of bacterial contamination. In the present study, we constructed a novel ADY strain with improved stress tolerance and ethanol fermentation performances under stressful conditions. The industrial Saccharomyces cerevisiae strain ZTW1 showed excellent properties and thus subjected to a modified whole-genome shuffling (WGS) process to improve its ethanol titer, proliferation capability, and multiple stress tolerance for ADY production. The best-performing mutant, Z3-86, was obtained after three rounds of WGS, producing 4.4% more ethanol and retaining 2.15-fold higher viability than ZTW1 after drying. Proteomics and physiological analyses indicated that the altered expression patterns of genes involved in protein metabolism, plasma membrane composition, trehalose metabolism, and oxidative responses contribute to the trait improvement of Z3-86. This work not only successfully developed a novel S. cerevisiae mutant for application in commercial bioethanol production, but also enriched the current understanding of how WGS improves the complex traits of microbes.

  4. Construction of novel Saccharomyces cerevisiae strains for bioethanol active dry yeast (ADY production.

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    Daoqiong Zheng

    Full Text Available The application of active dry yeast (ADY in bioethanol production simplifies operation processes and reduces the risk of bacterial contamination. In the present study, we constructed a novel ADY strain with improved stress tolerance and ethanol fermentation performances under stressful conditions. The industrial Saccharomyces cerevisiae strain ZTW1 showed excellent properties and thus subjected to a modified whole-genome shuffling (WGS process to improve its ethanol titer, proliferation capability, and multiple stress tolerance for ADY production. The best-performing mutant, Z3-86, was obtained after three rounds of WGS, producing 4.4% more ethanol and retaining 2.15-fold higher viability than ZTW1 after drying. Proteomics and physiological analyses indicated that the altered expression patterns of genes involved in protein metabolism, plasma membrane composition, trehalose metabolism, and oxidative responses contribute to the trait improvement of Z3-86. This work not only successfully developed a novel S. cerevisiae mutant for application in commercial bioethanol production, but also enriched the current understanding of how WGS improves the complex traits of microbes.

  5. COMPARATIVE ASSESSMENT OF THE LABORATORY SELECTED AND ACTIVE DRIED SACCHAROMYCES CEREVISIAE YEAST CULTURE IN BIOTECHNOLOGY OF THE BRANDY PRODUCTION

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    Bayraktar V.N.

    2015-04-01

    selected Saccharomyces cerevisiae yeast culture and Dry active commercial Saccharomyces cerevisiae yeast culture did not showed any difference in enzymatic activity. Both groups showed high enzymatic activity on the third day from the start of fermentation and decreasing on the fifth day since of fermentation started.

  6. The effects of active dried and killed dried yeast on subacute ruminal acidosis, ruminal fermentation, and nutrient digestibility in beef heifers.

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    Vyas, D; Uwizeye, A; Mohammed, R; Yang, W Z; Walker, N D; Beauchemin, K A

    2014-02-01

    The study addressed the importance of yeast (Saccharomyces cerevisiae) viability for reducing the incidence of subacute ruminal acidosis (SARA) and improving total tract nutrient digestibility in beef heifers. Six ruminally cannulated beef heifers (680 ± 50 kg BW) were used in a replicated 3 × 3 Latin square design and were fed a diet consisting of 40% barley silage, 10% chopped grass hay, and 50% barley grain-based concentrate (DM basis). Treatments were 1) no yeast (Control), 2) active dried yeast (ADY; 4 g providing 10(10) cfu/g; AB Vista, Marlborough, UK), and 3) killed dried yeast (KDY; 4 g autoclaved ADY). The treatments were directly dosed via the ruminal cannula daily at the time of feeding. The periods consisted of 2 wk of adaptation (d 1 to 14) and 7 d of measurements (d 15 to 21). Ruminal pH was continuously measured (d 15 to 21) using an indwelling system. Ruminal contents were sampled on d 15 and 17 at 0, 3, 6, 9, and 12 h after feeding. Total tract nutrient digestibility was measured using an external marker (YbCl3) from d 15 to 19. No treatment difference was observed for DMI (P = 0.86). Yeast supplementation (ADY and KDY) tended to increase total tract digestibility of starch (P = 0.07) whereas no effects were observed on digestibility of other nutrients. Both ADY and KDY elevated minimum (P yeast supplementation was effective in reducing time that ruminal pH was below 5.8 (P 0.10); however, the proportion of Ruminococcus flavefaciens in solid fraction of digesta was greater with KDY (P = 0.05). The study demonstrates the positive effects of yeast, irrespective of its viability, in reducing the severity of SARA. However, further studies are required to evaluate the importance of yeast viability for other dietary conditions, particularly when the risk of acidosis is high.

  7. Non-canonical regulation of glutathione and trehalose biosynthesis characterizes non-Saccharomyces wine yeasts with poor performance in active dry yeast production

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    Esther Gamero-Sandemetrio

    2018-01-01

    Full Text Available Several yeast species, belonging to Saccharomyces and non-Saccharomyces genera, play fundamental roles during spontaneous must grape fermentation, and recent studies have shown that mixed fermentations, co-inoculated with S. cerevisiae and non-Saccharomyces strains, can improve wine organoleptic properties. During active dry yeast (ADY production, antioxidant systems play an essential role in yeast survival and vitality as both biomass propagation and dehydration cause cellular oxidative stress and negatively affect technological performance. Mechanisms for adaptation and resistance to desiccation have been described for S. cerevisiae, but no data are available on the physiology and oxidative stress response of non-Saccharomyces wine yeasts and their potential impact on ADY production. In this study we analyzed the oxidative stress response in several non-Saccharomyces yeast species by measuring the activity of reactive oxygen species (ROS scavenging enzymes, e.g., catalase and glutathione reductase, accumulation of protective metabolites, e.g., trehalose and reduced glutathione (GSH, and lipid and protein oxidation levels. Our data suggest that non-canonical regulation of glutathione and trehalose biosynthesis could cause poor fermentative performance after ADY production, as it corroborates the corrective effect of antioxidant treatments, during biomass propagation, with both pure chemicals and food-grade argan oil.

  8. Differing effects of 2 active dried yeast (Saccharomyces cerevisiae) strains on ruminal acidosis and methane production in nonlactating dairy cows.

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    Chung, Y-H; Walker, N D; McGinn, S M; Beauchemin, K A

    2011-05-01

    Fifteen ruminally cannulated, nonlactating Holstein cows were used to measure the effects of 2 strains of Saccharomyces cerevisiae, fed as active dried yeasts, on ruminal pH and fermentation and enteric methane (CH(4)) emissions. Nonlactating cows were blocked by total duration (h) that their ruminal pH was below 5.8 during a 6-d pre-experimental period. Within each block, cows were randomly assigned to control (no yeast), yeast strain 1 (Levucell SC), or yeast strain 2 (a novel strain selected for enhanced in vitro fiber degradation), with both strains (Lallemand Animal Nutrition, Montréal, QC, Canada) providing 1 × 10(10) cfu/head per day. Cows were fed once daily a total mixed ration consisting of a 50:50 forage to concentrate ratio (dry matter basis). The yeast strains were dosed via the rumen cannula daily at the time of feeding. During the 35-d experiment, ruminal pH was measured continuously for 7 d (d 22 to 28) by using an indwelling system, and CH(4) gas was measured for 4 d (d 32 to 35) using the sulfur hexafluoride tracer gas technique (with halters and yokes). Rumen contents were sampled on 2 d (d 22 and 26) at 0, 3, and 6h after feeding. Dry matter intake, body weight, and apparent total-tract digestibility of nutrients were not affected by yeast feeding. Strain 2 decreased the average daily minimum (5.35 vs. 5.65 or 5.66), mean (5.98 vs. 6.24 or 6.34), and maximum ruminal pH (6.71 vs. 6.86 or 6.86), and prolonged the time that ruminal pH was below 5.8 (7.5 vs. 3.3 or 1.0 h/d) compared with the control or strain 1, respectively. The molar percentage of acetate was lower and that of propionate was greater in the ruminal fluid of cows receiving strain 2 compared with cows receiving no yeast or strain 1. Enteric CH(4) production adjusted for intake of dry matter or gross energy, however, did not differ between either yeast strain compared with the control but it tended to be reduced by 10% when strain 2 was compared with strain 1. The study shows that

  9. 21 CFR 573.750 - Pichia pastoris dried yeast.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Pichia pastoris dried yeast. 573.750 Section 573... Food Additive Listing § 573.750 Pichia pastoris dried yeast. (a) Identity. The food additive Pichia pastoris dried yeast may be used in feed formulations of broiler chickens as a source of protein not to...

  10. Changes in the relative population size of selected ruminal bacteria following an induced episode of acidosis in beef heifers receiving viable and non-viable active dried yeast.

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    Mohammed, R; Vyas, D; Yang, W Z; Beauchemin, K A

    2017-06-01

    To characterize the changes in the relative population size (RPS) of select ruminal bacteria and rumen fermentation variables in beef heifers supplemented with a strain of Saccharomyces cerevisiae as viable active dried (ADY) or killed dried (KDY) yeast following an induced episode of ruminal acidosis. Six ruminally cannulated beef heifers fed a diet consisting of 50% forage and 50% grain (dry matter basis) were used in a replicated 3 × 3 Latin square design with three 28-day periods. Treatments were: (i) control (CTRL; no yeast); (ii) ADY (4 g day -1 providing 10 10  CFU per g; AB Vista, UK); and (iii) KDY (4 g day -1 autoclaved ADY). The acidosis challenge was induced on day 22 and rumen samples were collected on day 15 (baseline; BASE), day 22 (challenge day; CHAL), and on day 29 (168th hour post acid challenge or recovery, REC) of each period. Over the study, duration of pH Yeast supplementation, irrespective of its viability, showed beneficial effects on ruminal pH variables in animals more susceptible to acidosis. Rumen microbial population was altered with the induction of severe acidosis. Most of the changes reverted back to baseline values during the recovery phase. Yeast supplementation reduced subacute rumen acidosis in the most susceptible cattle, but failed to attenuate severe acidosis induced by a grain challenge. The study provided valuable insight into the mechanism by which acidosis affects cattle performance. Individual animal variation in ruminal fermentation partly explained the variability in response to yeast supplementation in the study. © 2017 Her Majesty the Queen in Right of Canada. Journal of Applied Microbiology © 2017 The Society for Applied Microbiology.

  11. Reduction of oxidative cellular damage by overexpression of the thioredoxin TRX2 gene improves yield and quality of wine yeast dry active biomass

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    Ros Joaquim

    2010-02-01

    Full Text Available Abstract Background Wine Saccharomyces cerevisiae strains, adapted to anaerobic must fermentations, suffer oxidative stress when they are grown under aerobic conditions for biomass propagation in the industrial process of active dry yeast production. Oxidative metabolism of sugars favors high biomass yields but also causes increased oxidation damage of cell components. The overexpression of the TRX2 gene, coding for a thioredoxin, enhances oxidative stress resistance in a wine yeast strain model. The thioredoxin and also the glutathione/glutaredoxin system constitute the most important defense against oxidation. Trx2p is also involved in the regulation of Yap1p-driven transcriptional response against some reactive oxygen species. Results Laboratory scale simulations of the industrial active dry biomass production process demonstrate that TRX2 overexpression increases the wine yeast final biomass yield and also its fermentative capacity both after the batch and fed-batch phases. Microvinifications carried out with the modified strain show a fast start phenotype derived from its enhanced fermentative capacity and also increased content of beneficial aroma compounds. The modified strain displays an increased transcriptional response of Yap1p regulated genes and other oxidative stress related genes. Activities of antioxidant enzymes like Sod1p, Sod2p and catalase are also enhanced. Consequently, diminished oxidation of lipids and proteins is observed in the modified strain, which can explain the improved performance of the thioredoxin overexpressing strain. Conclusions We report several beneficial effects of overexpressing the thioredoxin gene TRX2 in a wine yeast strain. We show that this strain presents an enhanced redox defense. Increased yield of biomass production process in TRX2 overexpressing strain can be of special interest for several industrial applications.

  12. Drying enhances immunoactivity of spent brewer's yeast cell wall β-D-glucans.

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    Liepins, Janis; Kovačova, Elena; Shvirksts, Karlis; Grube, Mara; Rapoport, Alexander; Kogan, Grigorij

    2015-07-20

    Due to immunological activity, microbial cell wall polysaccharides are defined as 'biological response modifiers' (BRM). Cell walls of spent brewer's yeast also have some BRM activity. However, up to date there is no consensus on the use of spent brewer's yeast D-glucan as specific BRM in humans or animals. The aim of this paper is to demonstrate the potential of spent brewer's yeast β-D-glucans as BRM, and drying as an efficient pretreatment to increase β-D-glucan's immunogenic activity. Our results revealed that drying does not change spent brewer's yeast biomass carbohydrate content as well as the chemical structure of purified β-D-glucan. However, drying increased purified β-D-glucan TNF-α induction activity in the murine macrophage model. We presume drying pretreatment enhances purity of extracted β-D-glucan. This is corroborated with FT-IR analyses of the β-D-glucan spectra. Based on our results, we suggest that dry spent brewer's yeast biomass can be used as a cheap source for high-quality β-D-glucan extraction. Drying in combination with carboxylmethylation (CM), endows spent brewer's yeast β-D-glucan with the immunoactivity similar or exceeding that of a well-characterized fungal BRM pleuran. Copyright © 2015 Elsevier B.V. All rights reserved.

  13. Factors influencing ruminal bacterial community diversity and composition and microbial fibrolytic enzyme abundance in lactating dairy cows with a focus on the role of active dry yeast.

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    AlZahal, Ousama; Li, Fuyong; Guan, Le Luo; Walker, Nicola D; McBride, Brian W

    2017-06-01

    The objective of the current study was to employ a DNA-based sequencing technology to study the effect of active dry yeast (ADY) supplementation, diet type, and sample location within the rumen on rumen bacterial community diversity and composition, and to use an RNA-based method to study the effect of ADY supplementation on rumen microbial metabolism during high-grain feeding (HG). Our previous report demonstrated that the supplementation of lactating dairy cows with ADY attenuated the effect of subacute ruminal acidosis. Therefore, we used samples from that study, where 16 multiparous, rumen-cannulated lactating Holstein cows were randomly assigned to 1 of 2 dietary treatments: ADY (Saccharomyces cerevisiae strain Y1242, 80 billion cfu/animal per day) or control (carrier only). Cows received a high-forage diet (77:23, forage:concentrate), then were abruptly switched to HG (49:51, forage:concentrate). Rumen bacterial community diversity and structure were highly influenced by diet and sampling location (fluid, solids, epimural). The transition to HG reduced bacterial diversity, but epimural bacteria maintained a greater diversity than fluid and solids. Analysis of molecular variance indicated a significant separation due to diet × sampling location, but not due to treatment. Across all samples, the analysis yielded 6,254 nonsingleton operational taxonomic units (OTU), which were classified into several phyla: mainly Firmicutes, Bacteroidetes, Fibrobacteres, Tenericutes, and Proteobacteria. High forage and solids were dominated by OTU from Fibrobacter, whereas HG and fluid were dominated by OTU from Prevotella. Epimural samples, however, were dominated in part by Campylobacter. Active dry yeast had no effect on bacterial community diversity or structure. The phylum SR1 was more abundant in all ADY samples regardless of diet or sampling location. Furthermore, on HG, OTU2 and OTU3 (both classified into Fibrobacter succinogenes) were more abundant with ADY in fluid

  14. Performance of dairy goats fed diets with dry yeast from sugar cane as protein source

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    Luciano Soares de Lima

    2012-01-01

    Full Text Available The effects of inactive dry yeast (Saccharomyces cerevisiae from sugar cane were studied in 18 primiparus Saanen dairy goats (51.07±1.43 on dry matter intake and digestibility, milk production and quality. Animals were distributed in a completely randomized design during 90 days (from day 60 of milking. Diets were composed of soybean meal; soybean meal + dry yeast; or dry yeast, as protein sources, and ground corn, mineral supplement and corn silage (40%. Animals fed the dry yeast diet showed lower intake of dry matter (DM, organic matter (OM, crude protein, ether extract and neutral detergent fiber. Diets did not influence milk yield; however the milk production efficiency (kg of milk produced/kg of crude protein ingested was better in goats fed the dry yeast diet. Acidity, somatic cell counts and milk urea nitrogen values were not affected by treatments. Animals fed the soybean + dry yeast diet had higher fat and total solids than those fed the dry yeast diet. The digestibility of DM, OM and total carbohydrate was lower for soybean only and soybean + dry yeast diets. Total digestible nutrients were higher for dry yeast and soy bean diets than soybean + dry yeast diet. Dry yeast from sugar cane is a good alternative protein source for feeding lactating dairy goats and can be recommended because it maintains the production performance.

  15. Effect of yeast storage temperature and flour composition on fermentative activities of baker's yeast

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    Pejin Dušanka J.

    2009-01-01

    Full Text Available Baker's yeast is a set of living cells of Saccharomyces cerevisiae. It contains around 70-72% of water, 42-45% of proteins, around 40% of carbohydrates, around 7.5% of lipids (based on dry matter, and vitamin B-complex. On the basis of yeast cell analysis it can be concluded that yeast is a complex biological system which changes in time. The intensity of the changes depends on temperature. Yeast sample was stored at 4°C i 24°C for 12 days. During storage at 4°C, the content of total carbohydrates decreased from 48.81% to 37.50% (dry matter, whereas carbohydrate loss ranged from 40.81% to 29.28% at 24°C. The content of trehalose was 12.33% in the yeast sample stored at 4°C and 0.24% at 24°C. Loss of fermentative activity was 81.76% in the sample stored at 24°C for 12 days. The composition of five samples of 1st category flour was investigated. It was found that flours containing more reducing sugars and maltose enable higher fermentation activities. The flours with higher ash content (in the range 0.5-0.94% had higher contents of phytic acid. Higher ash and phytic contents in flour increased the yeast fermentative efficiency. In bakery industry, a range of ingredients has been applied to improve the product's quality such as surface active substances (emulsifiers, enzymes, sugars and fats. In the paper, the effect of some ingredients added to dough (margarine, saccharose, sodium chloride and malted barley on the yeast fermentative activity was studied. The mentioned ingredients were added to dough at different doses: 0.5, 1.0, 1.5 and 2.0%, flour basis. It was found that the investigated ingredients affected the fermentative activity of yeast and improved the bread quality.

  16. An Investigation into Rumen Fungal and Protozoal Diversity in Three Rumen Fractions, during High-Fiber or Grain-Induced Sub-Acute Ruminal Acidosis Conditions, with or without Active Dry Yeast Supplementation.

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    Ishaq, Suzanne L; AlZahal, Ousama; Walker, Nicola; McBride, Brian

    2017-01-01

    Sub-acute ruminal acidosis (SARA) is a gastrointestinal functional disorder in livestock characterized by low rumen pH, which reduces rumen function, microbial diversity, host performance, and host immune function. Dietary management is used to prevent SARA, often with yeast supplementation as a pH buffer. Almost nothing is known about the effect of SARA or yeast supplementation on ruminal protozoal and fungal diversity, despite their roles in fiber degradation. Dairy cows were switched from a high-fiber to high-grain diet abruptly to induce SARA, with and without active dry yeast (ADY, Saccharomyces cerevisiae ) supplementation, and sampled from the rumen fluid, solids, and epimural fractions to determine microbial diversity using the protozoal 18S rRNA and the fungal ITS1 genes via Illumina MiSeq sequencing. Diet-induced SARA dramatically increased the number and abundance of rare fungal taxa, even in fluid fractions where total reads were very low, and reduced protozoal diversity. SARA selected for more lactic-acid utilizing taxa, and fewer fiber-degrading taxa. ADY treatment increased fungal richness (OTUs) but not diversity (Inverse Simpson, Shannon), but increased protozoal richness and diversity in some fractions. ADY treatment itself significantly ( P PERMANOVA, P = 0.0001, P = 0.0452, P = 0.0068, Monte Carlo correction, respectively, and location was a significant factor ( P = 0.001, Monte Carlo correction) for protozoa. Diet-induced SARA shifts diversity of rumen fungi and protozoa and selects against fiber-degrading species. Supplementation with ADY mitigated this reduction in protozoa, presumptively by triggering microbial diversity shifts (as seen even in the high-fiber diet) that resulted in pH stabilization. ADY did not recover the initial community structure that was seen in pre-SARA conditions.

  17. An Investigation into Rumen Fungal and Protozoal Diversity in Three Rumen Fractions, during High-Fiber or Grain-Induced Sub-Acute Ruminal Acidosis Conditions, with or without Active Dry Yeast Supplementation

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    Suzanne L. Ishaq

    2017-10-01

    Full Text Available Sub-acute ruminal acidosis (SARA is a gastrointestinal functional disorder in livestock characterized by low rumen pH, which reduces rumen function, microbial diversity, host performance, and host immune function. Dietary management is used to prevent SARA, often with yeast supplementation as a pH buffer. Almost nothing is known about the effect of SARA or yeast supplementation on ruminal protozoal and fungal diversity, despite their roles in fiber degradation. Dairy cows were switched from a high-fiber to high-grain diet abruptly to induce SARA, with and without active dry yeast (ADY, Saccharomyces cerevisiae supplementation, and sampled from the rumen fluid, solids, and epimural fractions to determine microbial diversity using the protozoal 18S rRNA and the fungal ITS1 genes via Illumina MiSeq sequencing. Diet-induced SARA dramatically increased the number and abundance of rare fungal taxa, even in fluid fractions where total reads were very low, and reduced protozoal diversity. SARA selected for more lactic-acid utilizing taxa, and fewer fiber-degrading taxa. ADY treatment increased fungal richness (OTUs but not diversity (Inverse Simpson, Shannon, but increased protozoal richness and diversity in some fractions. ADY treatment itself significantly (P < 0.05 affected the abundance of numerous fungal genera as seen in the high-fiber diet: Lewia, Neocallimastix, and Phoma were increased, while Alternaria, Candida Orpinomyces, and Piromyces spp. were decreased. Likewise, for protozoa, ADY itself increased Isotricha intestinalis but decreased Entodinium furca spp. Multivariate analyses showed diet type was most significant in driving diversity, followed by yeast treatment, for AMOVA, ANOSIM, and weighted UniFrac. Diet, ADY, and location were all significant factors for fungi (PERMANOVA, P = 0.0001, P = 0.0452, P = 0.0068, Monte Carlo correction, respectively, and location was a significant factor (P = 0.001, Monte Carlo correction for protozoa

  18. Activation of waste brewer's yeast Saccharomyces cerevisiae for bread production

    OpenAIRE

    Popov Stevan D.; Dodić Siniša N.; Mastilović Jasna S.; Dodić Jelena M.; Popov-Raljić Jovanka V.

    2005-01-01

    The waste brewer's yeast S. cerevisiae (activated and non-activated) was compared with the commercial baker's yeast regarding the volume of developed gas in dough, volume and freshness stability of produced bread. The activation of waste brewer's yeast resulted in the increased volume of developed gas in dough by 100% compared to non-activated brewer's yeast, and the obtained bread is of more stable freshness compared to bread produced with baker's yeast. The activation of BY affects positive...

  19. Antioxidant N-acetyltransferase Mpr1/2 of industrial baker's yeast enhances fermentation ability after air-drying stress in bread dough.

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    Sasano, Yu; Takahashi, Shunsuke; Shima, Jun; Takagi, Hiroshi

    2010-03-31

    During bread-making processes, yeast cells are exposed to multiple stresses. Air-drying stress is one of the most harmful stresses by generation of reactive oxygen species (ROS). Previously, we discovered that the novel N-acetyltransferase Mpr1/2 confers oxidative stress tolerance by reducing intracellular ROS level in Saccharomyces cerevisiae Sigma1278b strain. In this study, we revealed that Japanese industrial baker's yeast possesses one MPR gene. The nucleotide sequence of the MPR gene in industrial baker's yeast was identical to the MPR2 gene in Sigma1278b strain. Gene disruption analysis showed that the MPR2 gene in industrial baker's yeast is involved in air-drying stress tolerance by reducing the intracellular oxidation levels. We also found that expression of the Lys63Arg and Phe65Leu variants with enhanced enzymatic activity and stability, respectively, increased the fermentation ability of bread dough after exposure to air-drying stress compared with the wild-type Mpr1. In addition, our recent study showed that industrial baker's yeast cells accumulating proline exhibited enhanced freeze tolerance in bread dough. Proline accumulation also enhanced the fermentation ability after air-drying stress treatment in industrial baker's yeast. Hence, the antioxidant enzyme Mpr1/2 could be promising for breeding novel yeast strains that are tolerant to air-drying stress. Copyright 2010 Elsevier B.V. All rights reserved.

  20. Instrumental neutron activation analysis of brewer's yeast

    International Nuclear Information System (INIS)

    Bergerioux, C.; Zikovsky, L.

    1978-01-01

    Instrumental neutron activation was used for the determination of 23 trace and minor elements in 4 different samples of brewer's yeast. Detection limits vary from 2 ppb to 100 ppm. The following average concentrations were found (ppm, dry weight): Al 597, Br 0.36, Cl 1473, Co 0.21, Cu 19, Fe 285, K 16400, Mg 1355, Mn 8.4, Na 2330, Rb 19, Sb 0.053, Se 1.2, V 2.2 and Zn 80. NBS standard 1569 was also analyzed and the following concentrations (in ppm) were measured: Al 2300, Br 0.65, Ce 0.23, Cl 460, Co 0.26, Cr 2.12, Cu 11, Fe 707, Gd 7.1, Hf 0.13, K 15500, Mg 1780, Mn 7, Na 510, Rb 16, Sb 0.075, Sc 0.18, Se 0.92, Th 3.7, Ti 38, U 0.49, V 4.1 and Zn 70. (author)

  1. Performance of Clarias gariepinus Fed Dried Brewer's Yeast (Saccharomyces cerevisiae) Slurry in Replacement for Soybean Meal.

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    Solomon, Shola Gabriel; Ataguba, Gabriel Arome; Itodo, Gabriel Enemona

    2017-01-01

    Following disparity of earlier results, this study tested the performance of African catfish Clarias gariepinus fed dried brewer's yeast slurry meal (DBYM) based diets. Fingerlings of C. gariepinus with pooled mean initial weight of 1.58 ± 0.01 g were stocked in hapas (1 m × 1 m × 1 m) immersed in an earthen pond at a density of 15 fish per cage. Five diets with increasing substitution of soybean meal with 25%, 50%, 75%, and 100% of dried brewer's yeast and a control without dried brewer's yeast (0% substitution) were evaluated for 8 weeks. Palatability of diets reduced with increasing levels of DBYM. Growth and utilization parameters such as weight gain, feed conversion ratio, protein efficiency ratio, and specific growth rate differed significantly ( p meal with DBYM in C. gariepinus feed is between 1% and 14% of dry matter.

  2. Post-fermentative production of glutathione by baker's yeast (S. cerevisiae) in compressed and dried forms.

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    Musatti, Alida; Manzoni, Matilde; Rollini, Manuela

    2013-01-25

    The study was aimed at investigating the best biotransformation conditions to increase intracellular glutathione (GSH) levels in samples of baker's yeast (Saccharomyces cerevisiae) employing either the commercially available compressed and dried forms. Glucose, GSH precursors amino acids, as well as other cofactors, were dissolved in a biotransformation solution and yeast cells were added (5%dcw). Two response surface central composite designs (RSCCDs) were performed in sequence: in the first step the influence of amino acid composition (cysteine, glycine, glutamic acid and serine) on GSH accumulation was investigated; once their formulation was set up, the influence of other components was studied. Initial GSH content was found 0.53 and 0.47%dcw for compressed and dried forms. GSH accumulation ability of baker's yeast in compressed form was higher at the beginning of shelf life, that is, in the first week, and a maximum of 2.04%dcw was obtained. Performance of yeast in dried form was not found satisfactory, as the maximum GSH level was 1.18%dcw. When cysteine lacks from the reaction solution, yeast cells do not accumulate GSH. With dried yeast, the highest GSH yields occurred when cysteine was set at 3 g/L, glycine and glutamic acid at least at 4 g/L, without serine. Employing compressed yeast, the highest GSH yields occurred when cysteine and glutamic acid were set at 2-3 g/L, while glycine and serine higher than 2 g/L. Results allowed to set up an optimal and feasible procedure to obtain GSH-enriched yeast biomass, with up to threefold increase with respect to initial content. Copyright © 2012 Elsevier B.V. All rights reserved.

  3. Production of freeze-dried yeast culture for the brewing of traditional sorghum beer, tchapalo.

    Science.gov (United States)

    N'Guessan, Florent K; Coulibaly, Hermann W; Alloue-Boraud, Mireille W A; Cot, Marlène; Djè, Koffi Marcellin

    2016-01-01

    Freeze-drying is a well-known dehydration method widely used to preserve microorganisms. In order to produce freeze-dried yeast starter culture for the brewing purpose of African sorghum beer, we tested protective agents (sucrose, glucose, glycerol) in combination with support materials (millet, maize, sorghum, and cassava flours) at 1:1 ratio (v/v). The yeast strains Saccharomyces cerevisiae F 12-7 and Candida tropicalis C 0-7 previously isolated from sorghum beer were used in a mixed culture at a ratio of 2:1 (C. tropicalis/S. cerevisiae). After the freeze-drying, the residual water contents were between 0.78 -2.27%, 0.55 -4.09%, and 0.40-2.61%, respectively, with sucrose, glucose and glycerol. The dried yeasts viabilities were between 4.0% and 10.6%. Among the protective agents used, sucrose was found to be the best protectant giving cell viabilities of 8.4-10.6%. Considering the support materials, millet flour was the best support after drying. When the freeze-dried yeast powders were stored at 4°C and room temperature (25-28°C) for up to 3 months, the survival rates were the highest with cassava flour as the support material.

  4. Electron beam radiation of dried fruits and nuts to reduce yeast and mold bioburden.

    Science.gov (United States)

    Ic, Erhan; Kottapalli, Bala; Maxim, Joseph; Pillai, Suresh D

    2007-04-01

    Dried fruits and nuts make up a significant portion of the commodities traded globally, and the presence of yeasts and molds on dried fruits and nuts can be a public health risk because of the potential for exposure to toxigenic fungi. Since current postharvest treatment technologies are rather limited for dried fruits and nuts, electron beam (E-beam) radiation experiments were performed to determine the doses required to reduce the yeast and mold bioburden of raisins, walnuts, and dates. The indigenous yeast and mold bioburden on a select number of commodities sold at retail ranged from 10(2) to 10(3) CFU/g. E-beam inactivation kinetics based on the linear model suggest that the decimal reduction dose required to eliminate 90% of the microbial population (D10-value) of these indigenous fungal populations ranges from 1.09 to 1.59 kGy. Some samples, however, exhibited inactivation kinetics that were better modeled by a quadratic model. The results indicate that different commodities can contain molds and yeasts of varying resistance to ionizing radiation. It is thus essential for the dried fruit and nut industry to determine empirically the minimum E-beam dose that is capable of reducing or eliminating the bioburden of yeasts and molds in their specific commodities.

  5. Freeze-drying of filamentous fungi and yeasts

    NARCIS (Netherlands)

    Tan, C.S.

    2011-01-01

    The aim of this thesis was to optimize the freeze-drying protocol for fungi in general and for those genera that do not survive this preservation method, in particular. To this end, the influence of the cooling rate, the lyoprotectant and the drying process itself was examined. Since most fungi

  6. Determination of chromium in Bowen's kale, NBS bovine liver, and brewers yeast, before and after dry ashing

    International Nuclear Information System (INIS)

    Versieck, J.; Hoste, J.; De Rudder, J.; Barbier, F.; Vanballenberghe, L.

    1979-01-01

    In view of the persistent controversy about the volatility of chromium in biologic materials, the element was determined by neutron activation analysis in three reference materials before and after dry ashing up to 450 0 C. The following mean values were obtained: 0.364 μg/g and 0.362 μg/g (Bowen's kale), 0.0806 μg/g and 0.0789 μg/g (NBS bovine liver), 2.043 μg/g and 2.094 μg/g (NBS brewers yeast). It was concluded that chromium does not volatilize significantly in experimental conditions of drying and ashing

  7. Characterization of ß-Glucans Isolated from Brewer’s Yeast and Dried by Different Methods

    Directory of Open Access Journals (Sweden)

    Vesna Zechner-Krpan

    2010-01-01

    Full Text Available Two different procedures have been used for isolation of water-insoluble ß-glucans from brewer’s yeast: alkaline-acidic isolation (AA and alkaline-acidic isolation with mannoprotein removal (AAM. The obtained ß-glucans were then dried by air-drying, lyophilization and combination of sonication and spray-drying. ß-Glucan preparations obtained by AA and AAM isolations had similar values of dry mass, total polysaccharides, proteins and organic elemental microanalysis. The mass fractions of ß-glucan in total polysaccharides were significantly affected by different isolation procedures. Fourier transform infrared (FTIR spectra of all preparations had the appearance typical for (1→3-ß-D-glucan. Lyophilization and especially air-drying caused a higher degree of agglomeration and changes in ß-glucan microstructure. Sonication followed by spray-drying resulted in minimal structural changes and negligible formation of agglomerates.

  8. Noninvasive characterization of the fission yeast cell cycle by monitoring dry mass with digital holographic microscopy.

    Science.gov (United States)

    Rappaz, Benjamin; Cano, Elena; Colomb, Tristan; Kühn, Jonas; Depeursinge, Christian; Simanis, Viesturs; Magistretti, Pierre J; Marquet, Pierre

    2009-01-01

    Digital holography microscopy (DHM) is an optical technique which provides phase images yielding quantitative information about cell structure and cellular dynamics. Furthermore, the quantitative phase images allow the derivation of other parameters, including dry mass production, density, and spatial distribution. We have applied DHM to study the dry mass production rate and the dry mass surface density in wild-type and mutant fission yeast cells. Our study demonstrates the applicability of DHM as a tool for label-free quantitative analysis of the cell cycle and opens the possibility for its use in high-throughput screening.

  9. Microbial ecology of extreme environments: Antarctic dry valley yeasts and growth in substrate limited habitats

    Science.gov (United States)

    Vishniac, H. S.

    1981-01-01

    The multiple stresses temperature, moisture, and for chemoheterotrophs, sources of carbon and energy of the Dry Valley Antarctica soils allow at best depauperate communities, low in species diversity and population density. The nature of community structure, the operation of biogeochemical cycles, the evolution and mechanisms of adaptation to this habitat are of interest in informing speculations upon life on other planets as well as in modeling the limits of gene life. Yeasts of the Cryptococcus vishniacil complex (Basidiobiastomycetes) are investigated, as the only known indigenes of the most hostile, lichen free, parts of the Dry Valleys. Methods were developed for isolating these yeasts (methods which do not exclude the recovery of other microbiota). The definition of the complex was refined and the importance of nitrogen sources was established as well as substrate competition in fitness to the Dry Valley habitats.

  10. Yeast diversity and dynamics in the production processes of Norwegian dry-cured meat products.

    Science.gov (United States)

    Asefa, Dereje T; Møretrø, Trond; Gjerde, Ragnhild O; Langsrud, Solveig; Kure, Cathrine F; Sidhu, Maan S; Nesbakken, Truls; Skaar, Ida

    2009-07-31

    This study investigate the diversity and dynamics of yeasts in the production processes of one unsmoked and two smoked dry-cured meat products of a Norwegian dry-cured meat production facility. A longitudinal observational study was performed to collect 642 samples from the meat, production materials, room installations and indoor and outdoor air of the production facility. Nutrient rich agar media were used to isolate the yeasts. Morphologically different isolates were re-cultivated in their pure culture forms. Both classical and molecular methods were employed for species identification. Totally, 401 yeast isolates belonging to 10 species of the following six genera were identified: Debaryomyces, Candida, Rhodotorula, Rhodosporidium, Cryptococcus and Sporidiobolus. Debaryomyces hansenii and Candida zeylanoides were dominant and contributed by 63.0% and 26.4% respectively to the total isolates recovered from both smoked and unsmoked products. The yeast diversity was higher at the pre-salting production processes with C. zeylanoides being the dominant. Later at the post-salting stages, D. hansenii occurred frequently. Laboratory studies showed that D. hansenii was more tolerant to sodium chloride and nitrite than C. zeylanoides. Smoking seems to have a killing or a temporary growth inhibiting effect on yeasts that extend to the start of the drying process. Yeasts were isolated only from 31.1% of the environmental samples. They belonged to six different species of which five of them were isolated from the meat samples too. Debaryomyces hansenii and Rhodotorula glutinis were dominant with a 62.6% and 22.0% contribution respectively. As none of the air samples contained D. hansenii, the production materials and room installations used in the production processes were believed to be the sources of contamination. The dominance of D. hansenii late in the production process replacing C. zeylanoides should be considered as a positive change both for the quality and safety

  11. Microbial ecology of extreme environments: Antarctic dry valley yeasts and growth in substrate-limited habitats

    Science.gov (United States)

    Vishniac, H. S.

    1982-01-01

    The success of the Antarctic Dry Valley yeasts presumeably results from adaptations to multiple stresses, to low temperatures and substrate-limitation as well as prolonged resting periods enforced by low water availability. Previous investigations have suggested that the crucial stress is substrate limitation. Specific adaptations may be pinpointed by comparing the physiology of the Cryptococcus vishniacii complex, the yeasts of the Tyrol Valley, with their congeners from other habitats. Progress was made in methods of isolation and definition of ecological niches, in the design of experiments in competition for limited substrate, and in establishing the relationships of the Cryptococcus vishniacii complex with other yeasts. In the course of investigating relationships, a new method for 25SrRNA homology was developed. For the first time it appears that 25SrRNA homology may reflect parallel or convergent evolution.

  12. Effect of heat treatment on brewer's yeast fermentation activity

    OpenAIRE

    Kharandiuk, Tetiana; Kosiv, Ruslana; Palianytsia, Liubov; Berezovska, Natalia

    2015-01-01

    The influence of temperature treatment of brewer's yeast strain Saflager W-34/70 at temperatures of -17, 20, 25, 30, 35, 40 °C on their fermentative activity was studied. It was established that the freezing of yeast leads to a decrease of fermentation activity in directly proportional to the duration way. Fermentative activity of yeast samples can be increased by 20-24% by heat treatment at 35 °C during 15-30 minutes.

  13. Construction of the yeast whole-cell Rhizopus oryzae lipase biocatalyst with high activity.

    Science.gov (United States)

    Chen, Mei-ling; Guo, Qin; Wang, Rui-zhi; Xu, Juan; Zhou, Chen-wei; Ruan, Hui; He, Guo-qing

    2011-07-01

    Surface display is effectively utilized to construct a whole-cell biocatalyst. Codon optimization has been proven to be effective in maximizing production of heterologous proteins in yeast. Here, the cDNA sequence of Rhizopus oryzae lipase (ROL) was optimized and synthesized according to the codon bias of Saccharomyces cerevisiae, and based on the Saccharomyces cerevisiae cell surface display system with α-agglutinin as an anchor, recombinant yeast displaying fully codon-optimized ROL with high activity was successfully constructed. Compared with the wild-type ROL-displaying yeast, the activity of the codon-optimized ROL yeast whole-cell biocatalyst (25 U/g dried cells) was 12.8-fold higher in a hydrolysis reaction using p-nitrophenyl palmitate (pNPP) as the substrate. To our knowledge, this was the first attempt to combine the techniques of yeast surface display and codon optimization for whole-cell biocatalyst construction. Consequently, the yeast whole-cell ROL biocatalyst was constructed with high activity. The optimum pH and temperature for the yeast whole-cell ROL biocatalyst were pH 7.0 and 40 °C. Furthermore, this whole-cell biocatalyst was applied to the hydrolysis of tributyrin and the resulted conversion of butyric acid reached 96.91% after 144 h.

  14. Activation of waste brewer's yeast Saccharomyces cerevisiae for bread production

    Directory of Open Access Journals (Sweden)

    Popov Stevan D.

    2005-01-01

    Full Text Available The waste brewer's yeast S. cerevisiae (activated and non-activated was compared with the commercial baker's yeast regarding the volume of developed gas in dough, volume and freshness stability of produced bread. The activation of waste brewer's yeast resulted in the increased volume of developed gas in dough by 100% compared to non-activated brewer's yeast, and the obtained bread is of more stable freshness compared to bread produced with baker's yeast. The activation of BY affects positively the quality of produced bread regarding bread volume. The volume of developed gas in dough prepared with the use of non-activated BY was not sufficient, therefore, it should not be used as fermentation agent, but only as an additive in bread production process for bread freshness preservation. Intense mixing of dough results in more compressible crumb 48 hrs after baking compared to high-speed mixing.

  15. Impact of glutathione-enriched inactive dry yeast preparations on the stability of terpenes during model wine aging.

    Science.gov (United States)

    Rodríguez-Bencomo, Juan José; Andújar-Ortiz, Inmaculada; Moreno-Arribas, M Victoria; Simó, Carolina; González, Javier; Chana, Antonio; Dávalos, Juan; Pozo-Bayón, M Ángeles

    2014-02-12

    The impact of the addition of glutathione-enriched Inactive dry yeast preparations (g-IDYs) on the stability of some typical wine terpenes (linalool, α-terpineol, β-citronellol, and nerol) stored under accelerated oxidative conditions was evaluated in model wines. Additionally, the effects of a second type of IDY preparation with a different claim (fermentative nutrient) and the sole addition of commercial glutathione into the model wines were also assessed. Model wines were spiked with the low molecular weight fraction (loss of typical wine terpenes in model wines submitted to accelerated aging conditions. The g-IDY preparation did indeed release reduced GSH into the model wines, although this compound did not seem exclusively related to the protective effect on some aroma compounds determined in both model wines. The presence of other sulfur-containing compounds from yeast origin in g-IDY, and also the presence of small yeast peptides, such as methionine/tryptophan/tyrosine-containing tripeptide in both types of IDYs, seemed to be related to the antioxidant activity determined in the two permeates and to the minor loss of some terpenes in the model wines spiked with them.

  16. Conditions of activation of yeast plasma membrane ATPase.

    Science.gov (United States)

    Sychrová, H; Kotyk, A

    1985-04-08

    The in vivo activation of the H+-ATPase of baker's yeast plasma membrane found by Serrano in 1983 was demonstrated with D-glucose aerobically and anaerobically (as well as in a respiration-deficient mutant) and, after suitable induction, with maltose, trehalose, and galactose. The activated but not the control ATPase was sensitive to oligomycin. No activation was possible in a cell-free extract with added glucose. The ATPase was not activated in yeast protoplasts which may account for the absence of glucose-stimulated secondary active transports in these wall-less cells and provide support for a microscopic coupling between ATPase activity and these transports in yeast cells.

  17. Antimicrobial activity of yeasts against some pathogenic bacteria

    Directory of Open Access Journals (Sweden)

    Gamal Younis

    2017-08-01

    Full Text Available Aim: This study was designed to isolate and identify yeast species from milk and meat products, and to test their antimicrobial activity against some bacterial species. Materials and Methods: A total of 160 milk and meat products samples were collected from random sellers and super markets in New Damietta city, Damietta, Egypt. Samples were subjected to yeast isolation procedures and tested for its antimicrobial activity against Staphylococcus aureus, Pseudomonas aeruginosa, and Escherichia coli. In addition, all yeast species isolates were subjected to polymerase chain reaction (PCR for detection of khs (kievitone hydratase and pelA (pectate degrading enzyme genes. Results: The recovery rate of yeasts from sausage was 20% (2/10 followed by kareish cheese, processed cheese, and butter 10% (1/10 each as well as raw milk 9% (9/100, and fruit yoghurt 30% (6/20. Different yeast species were recovered, namely, Candida kefyr (5 isolates, Saccharomyces cerevisiae (4 isolates, Candida intermedia (3 isolates, Candida tropicalis (2 isolates, Candida lusitaniae (2 isolates, and Candida krusei (1 isolate. khs gene was detected in all S. cerevisiae isolates, however, pelA gene was not detected in all identified yeast species. Antimicrobial activity of recovered yeasts against the selected bacterial species showed high activity with C. intermedia against S. aureus and E. coli, C. kefyr against E. coli, and C. lusitaniae against S. aureus. Moderate activities were obtained with C. tropicalis, C. lusitaniae, and S. cerevisiae against E. coli; meanwhile, all the tested yeasts revealed a very low antimicrobial activity against P. aeruginosa. Conclusion: The obtained results confirmed that some kinds of yeasts have the ability to produce antimicrobial compounds that could inhibit some pathogenic and spoilage bacteria and these antimicrobial activity of yeasts enables them to be one of the novel agents in controlling spoilage of food.

  18. Kinetics of the oxygen effect in yeast irradiated in dry and wet conditions

    International Nuclear Information System (INIS)

    Kiefer, J.; Schoepfer, F.; Luggen-Hoelscher, J.

    1981-01-01

    There are indications that the radiobiological oxygen-effect consists of more than one component: in dry bacterial spores three different classes can be separated depending on exposure- and after-treatment conditions, the dependence of the oxygen-enhancement ratio (OER) on oxygen concentration shows breaks in various systems, and it has been suggested that type O and type N damage are localized in different parts of the cells. These questions were studied in the simple eucaryote Saccharomyces cerevisiae using two approaches: the dependence of OER on oxygen tension was determined both for survivial and mutation induction. Since a forward mutation was used a haploid strain had to be employed in this case. In order to assess whether also in yeast cells more than one component may exist, the techniques originally developed for bacterial spores were adapted for dried diploid yeast cells. The results show that the dependence on oxygen concentration is the same for survival and mutation within error limits, implicating DNA as the main target and that also in our system three classes of oxygen dependent damage exist

  19. Differentiation of enzymatic activity of yeasts and yeast-like microorganisms isolated from various environments

    Directory of Open Access Journals (Sweden)

    Elżbieta Bogusławska-Wąs

    2014-08-01

    Full Text Available The aim of study was to determinate enzymatic activity of yeast-like organisms - Candida lipolytica, Rhodotorula rubra, Trichosporon beigelii, Zygosaccharomyces sp. - isolated from the Szczecin Lagoon and herring salads. We have shown that lipolytic activity was higher than protcolytic for every strain tested. The lowest activity level was found out for amylolytic hydrolases. The results also demonstrated that yeast-like organisms isolated from the Szczecin Lagoon revealed much higher average enzymatic activity compared to tbe same species isolated from herring salads, excepting C. lipolytica.

  20. Dry-grind processing using amylase corn and superior yeast to reduce the exogenous enzyme requirements in bioethanol production.

    Science.gov (United States)

    Kumar, Deepak; Singh, Vijay

    2016-01-01

    Conventional corn dry-grind ethanol production process requires exogenous alpha and glucoamylases enzymes to breakdown starch into glucose, which is fermented to ethanol by yeast. This study evaluates the potential use of new genetically engineered corn and yeast, which can eliminate or minimize the use of these external enzymes, improve the economics and process efficiencies, and simplify the process. An approach of in situ ethanol removal during fermentation was also investigated for its potential to improve the efficiency of high-solid fermentation, which can significantly reduce the downstream ethanol and co-product recovery cost. The fermentation of amylase corn (producing endogenous α-amylase) using conventional yeast and no addition of exogenous α-amylase resulted in ethanol concentration of 4.1 % higher compared to control treatment (conventional corn using exogenous α-amylase). Conventional corn processed with exogenous α-amylase and superior yeast (producing glucoamylase or GA) with no exogenous glucoamylase addition resulted in ethanol concentration similar to control treatment (conventional yeast with exogenous glucoamylase addition). Combination of amylase corn and superior yeast required only 25 % of recommended glucoamylase dose to complete fermentation and achieve ethanol concentration and yield similar to control treatment (conventional corn with exogenous α-amylase, conventional yeast with exogenous glucoamylase). Use of superior yeast with 50 % GA addition resulted in similar increases in yield for conventional or amylase corn of approximately 7 % compared to that of control treatment. Combination of amylase corn, superior yeast, and in situ ethanol removal resulted in a process that allowed complete fermentation of 40 % slurry solids with only 50 % of exogenous GA enzyme requirements and 64.6 % higher ethanol yield compared to that of conventional process. Use of amylase corn and superior yeast in the dry-grind processing industry

  1. Brewer’s Yeast, Saccharomyces cerevisiae, Enhances Attraction of Two Invasive Yellowjackets (Hymenoptera: Vespidae) to Dried Fruit and Fruit Powder

    Science.gov (United States)

    Gries, Regine; Borden, John; Palmero, Luis; Mattiacci, Analía; Masciocchi, Maité; Corley, Juan; Gries, Gerhard

    2017-01-01

    Abstract The German yellowjacket, Vespula germanica F., and common yellowjacket, Vespula vulgaris L. (Hymenoptera: Vespidae), are pests of significant economic, environmental, and medical importance in many countries. There is a need for the development and improvement of attractive baits that can be deployed in traps to capture and kill these wasps in areas where they are a problem. Yellowjackets are known to feed on fermenting fruit, but this resource is seldom considered as a bait due to its ephemeral nature and its potential attractiveness to nontarget species. We analyzed the headspace volatiles of dried fruit and fruit powder baits with and without Brewer’s yeast, Saccharomyces cerevisiae, using gas chromatography–mass spectrometry, and we field tested these baits for their attractiveness to yellowjackets in Argentina. The addition of yeast to dried fruit and fruit powder changed the volatile compositions, increasing the number of alcohols and acids and decreasing the number of aldehydes. Dried fruit and fruit powder baits on their own were hardly attractive to yellowjackets, but the addition of yeast improved their attractiveness by 9- to 50-fold and surpassed the attractiveness of a commercial heptyl butyrate-based wasp lure. We suggest that further research be done to test additional varieties and species of yeasts. A dried fruit or fruit powder bait in combination with yeast could become a useful tool in the management of yellowjackets. PMID:28922898

  2. Brewer's Yeast, Saccharomyces cerevisiae, Enhances Attraction of Two Invasive Yellowjackets (Hymenoptera: Vespidae) to Dried Fruit and Fruit Powder.

    Science.gov (United States)

    Babcock, Tamara; Gries, Regine; Borden, John; Palmero, Luis; Mattiacci, Analía; Masciocchi, Maité; Corley, Juan; Gries, Gerhard

    2017-09-01

    The German yellowjacket, Vespula germanica F., and common yellowjacket, Vespula vulgaris L. (Hymenoptera: Vespidae), are pests of significant economic, environmental, and medical importance in many countries. There is a need for the development and improvement of attractive baits that can be deployed in traps to capture and kill these wasps in areas where they are a problem. Yellowjackets are known to feed on fermenting fruit, but this resource is seldom considered as a bait due to its ephemeral nature and its potential attractiveness to nontarget species. We analyzed the headspace volatiles of dried fruit and fruit powder baits with and without Brewer's yeast, Saccharomyces cerevisiae, using gas chromatography-mass spectrometry, and we field tested these baits for their attractiveness to yellowjackets in Argentina. The addition of yeast to dried fruit and fruit powder changed the volatile compositions, increasing the number of alcohols and acids and decreasing the number of aldehydes. Dried fruit and fruit powder baits on their own were hardly attractive to yellowjackets, but the addition of yeast improved their attractiveness by 9- to 50-fold and surpassed the attractiveness of a commercial heptyl butyrate-based wasp lure. We suggest that further research be done to test additional varieties and species of yeasts. A dried fruit or fruit powder bait in combination with yeast could become a useful tool in the management of yellowjackets. © The Author 2017. Published by Oxford University Press on behalf of Entomological Society of America.

  3. Antioxidant and Anticancer activities of yeast grown on commercial ...

    African Journals Online (AJOL)

    E-mail: chemist_aml_said@yahoo.com. ABSTRACT ... INTRODUCTION. Yeasts have a positive image with ... production of antioxidant activity compounds. However, the .... were analyzed using an inverted microscope. (Nikon-Japan).

  4. PENGARUH BERBAGAI MERK DRIED YEAST (Saccharomyces sp. DAN pH AWAL FERMENTASI TERHADAP KARAKTERISTIK WINE SALAK

    Directory of Open Access Journals (Sweden)

    Ida Bagus Wayan Gunam

    2017-09-01

    Full Text Available The purpose of this research were to find out the effect of different of dried yeast and initial pH of fermentation on the characteristic of salacca wine, and to determine the appropriate of kind of dried yeast and initial pH of fermentation to produce salacca wine with the best characteristic. This research used Randomized Block Design with factorial pattern. The first factor was the kind of dried yeast brand that consisted of 3 kinds namely Lalvin, Levure and Alcotec. The second factor consisted of 5 levels of initial pH, namely 3.5; 4; 4.5; 5; and 5.5. Each treatment was done 2 times, in order to obtain 30 trial units. The data obtained was analyzed using ANOVA followed by Duncans test. Interactions between treatments had very significant effect on the ethanol content, reduction sugar content, and pH, but had significant effect on acid total content. The best treatment was to use the Alcotec brand dried yeast with a treatment of initial pH as 4, with the following characteristics: ethanol content 12.40%, negative content of methanol, reduction sugar content 5.87%, acid total content 0.20%, pH 3.5 after the fermentation, the color was enough pure yellow, the flavor was strong enough, the taste was strong enough, and rather liked over all acceptance.

  5. Alteration of yeast activity by gamma radiation

    International Nuclear Information System (INIS)

    Chacharkar, M.P.; Tak, B.B.; Bhati, J.

    1996-01-01

    Yeast is an important component in microbe based industrial technologies. Due to the techno-economic reasons, the fermentation technique has acquired renewed interest. The effect of γ-radiation on the fermentation reaction has been investigated. The studies show that exposure of the fermentation mixture to γ-radiation at 5 kGy enhance alcohol production, whereas irradiation at higher doses, viz., 10 kGy and 25 kGy caused a considerable reduction in the alcohol yield. Therefore, low dose irradiation of fermentation mixtures can be applied for increasing the alcohol production by about 25%. (author). 13 refs., 1 fig

  6. Yeast and yeast-like fungi associated with dry indehiscent fruits of Nothofagus nervosa in Patagonia, Argentina.

    Science.gov (United States)

    Fernández, Natalia V; Mestre, M Cecilia; Marchelli, Paula; Fontenla, Sonia B

    2012-04-01

    Nothofagus nervosa (Raulí) is a native tree species that yields valuable timber. It was overexploited in the past and is currently included in domestication and conservation programs. Several research programs have focused on the characterization of epiphytic microorganisms because it has been demonstrated that they can affect plant-pathogen interactions and/or promote plant growth. Although the microbial ecology of leaves has been well studied, less is known about microorganisms occurring on seeds and noncommercial fruits. In this work, we analyzed the yeast and yeast-like fungi present on N. nervosa fruits destined for the propagation of this species, as well as the effects of fruit preservation and seed dormancy-breaking processes on fungal diversity. Morphological and molecular methods were used, and differences between fungal communities were analyzed using a similarity index. A total of 171 isolates corresponding to 17 species were recovered, most of which belong to the phylum Ascomycota. The majority of the species develop mycelia, produce pigments and mycosporines, and these adaptation strategies are discussed. It was observed that the preservation process considerably reduced yeast and yeast-like fungal diversity. This is the first study concerning microbial communities associated with this ecologically and economically important species, and the information presented is relevant to domestication programs. © 2011 Federation of European Microbiological Societies. Published by Blackwell Publishing Ltd. All rights reserved.

  7. Isolation of a tyrosine-activating enzyme from baker's yeast

    NARCIS (Netherlands)

    Ven, A.M. van de; Koningsberger, V.V.; Overbeek, J.Th.G.

    1958-01-01

    The extracts of ether-CO2-frozen baker's yeast contain enzymes that catalyze the ATP-linked amino acid activation by way of pyrophosphate elimination. From the extract a tyrosine-activating enzyme could be isolated, which, judging from ultracentrifugation and electrophoretic data, was about 70% pure

  8. Isolation of a yeast strain able to produce a polygalacturonase with maceration activity of cassava roots

    Directory of Open Access Journals (Sweden)

    María Alicia Martos

    2013-06-01

    Full Text Available The objective of the present study was the isolation of a yeast strain, from citrus fruit peels, able to produce a polygalacturonase by submerged fermentation with maceration activity of raw cassava roots. Among 160 yeast strains isolated from citrus peels, one strain exhibited the strongest pectinolytic activity. This yeast was identified as Wickerhamomyces anomalus by 5.8S-ITS RFLP analysis and confirmed by amplification of the nucleotide sequence. The yeast produced a polygalacturonase (PG in Erlenmeyer shake flasks containing YNB, glucose, and citrus pectin. PG synthesis occurred during exponential growth phase, reaching 51 UE.mL-1 after 8 hours of fermentation. A growth yield (Yx/s of 0.43 gram of cell dry weight per gram of glucose consumed was obtained, and a maximal specific growth rate (µm of 0.346 h-1 was calculated. The microorganism was unable to assimilate sucrose, galacturonic acid, polygalacturonic acid, or citrus pectin, but it required glucose as carbon and energy source and polygalacturonic acid or citrus pectin as inducers of enzyme synthesis. The crude enzymatic extract of Wickerhamomyces anomalus showed macerating activity of raw cassava. This property is very important in the production of dehydrated mashed cassava, a product of regional interest in the province of Misiones, Argentina.

  9. Effects of the usage of dried brewing yeast in the diets on the performance, egg traits and blood parameters in quails.

    Science.gov (United States)

    Yalçın, S; Erol, H; Ozsoy, B; Onbaşılar, I; Yalçın, S

    2008-12-01

    This experiment was carried out to determine the effects of the usage of dried brewing yeast in quail diets on laying performance, egg traits and blood parameters. A total of 240 Japanese quails (Coturnix coturnix japonica) aged 10 weeks were randomly allocated into one control group and three treatment groups. Each group was divided into five replicates as subgroups, comprising 12 quails each. Dried brewing yeast (Saccharomyces cerevisiae) was used at the levels of 1.5%, 3.0% and 4.5% in the diets of the first, second and third treatment groups, respectively. Soyabean meal was replaced with dried brewing yeast. The diets were formulated to be isocaloric and isonitrogenous. The experimental period lasted 18 weeks. Dietary treatments did not significantly affect body weight, daily feed intake, daily protein intake, egg production, egg weight, feed efficiency, mortality, egg shell thickness, egg albumen index, egg yolk index, egg Haugh unit, the percentages of egg shell, albumen and yolk, excreta moisture and small intestinal pH. Inclusion of 3% and 4.5% dried brewing yeast in diets reduced egg yolk cholesterol concentration as mg per yolk and mg per g yolk (P brewing yeast was significantly lower (P brewing yeast resulted in significant increases (P brewing yeast. It is concluded that dried brewing yeast can be used up to 4.5% in the diets of laying quails without adverse effects on the measured parameters.

  10. Impact of glutathione-enriched inactive dry yeast preparations on the stability of terpenes during model wine aging

    OpenAIRE

    Rodríguez-Bencomo, Juan José; Andújar-Ortiz, Inmaculada; Moreno-Arribas, M. Victoria; Simó, Carolina; González, Javier; Chana, Antonio; Dávalos, J.Z.; Pozo-Bayón, Mª Ángeles

    2014-01-01

    The impact of the addition of glutathione-enriched Inactive dry yeast preparations (g-IDYs) on the stability of some typical wine terpenes (linalool, α-terpineol, β-citronellol, and nerol) stored under accelerated oxidative conditions was evaluated in model wines. Additionally, the effects of a second type of IDY preparation with a different claim (fermentative nutrient) and the sole addition of commercial glutathione into the model wines were also assessed. Model wines were spiked with the l...

  11. Proteolytic activities in yeast after UV irradiation. Pt. 1

    International Nuclear Information System (INIS)

    Schwencke, J.; Moustacchi, E.

    1982-01-01

    Specific proteolytic activities are known to be induced in Escherichia coli following irradiation. Consequently it seemed of interest to investigate whether variations in proteinase activities occur in yeast. Among the five most well known proteinases of Saccharomyces cerevisiae, we have found that proteinase B activity increases up to three times in wild-type RAD + yeast cells after a dose of 50 Jm -2 of 254 nm ultraviolet light (40% survival). Carboxypeptidase Y and aminopeptidase I (leucin aminopeptidase) activities were only moderately increased. Proteinase A activity was only slightly enhanced, while aminopeptidase II (lysin aminopeptidase) was unaffected in both RAD + strains studied. The observed post UV-increase in proteinase B activity was inhibited by cycloheximide and was dose dependent. Increases in proteinase B levels were independent of the activation method used to destroy the proteinase B-inhibitor complex present in the crude yeast extracts. A standard method for comparison of the postirradiation levels among different proteinases, strains and methods of activation is presented. (orig.)

  12. Proteolytic activities in yeast after UV irradiation. Pt. 1

    Energy Technology Data Exchange (ETDEWEB)

    Schwencke, J.; Moustacchi, E.

    1982-04-01

    Specific proteolytic activities are known to be induced in Escherichia coli following irradiation. Consequently it seemed of interest to investigate whether variations in proteinase activities occur in yeast. Among the five most well known proteinases of Saccharomyces cerevisiae, we have found that proteinase B activity increases up to three times in wild-type RAD/sup +/ yeast cells after a dose of 50 Jm/sup -2/ of 254 nm ultraviolet light (40% survival). Carboxypeptidase Y and aminopeptidase I (leucin aminopeptidase) activities were only moderately increased. Proteinase A activity was only slightly enhanced, while aminopeptidase II (lysin aminopeptidase) was unaffected in both RAD/sup +/ strains studied. The observed post UV-increase in proteinase B activity was inhibited by cycloheximide and was dose dependent. Increases in proteinase B levels were independent of the activation method used to destroy the proteinase B-inhibitor complex present in the crude yeast extracts. A standard method for comparison of the postirradiation levels among different proteinases, strains and methods of activation is presented.

  13. Evaluation of pectinolytic activities for oenological uses from psychrotrophic yeasts.

    Science.gov (United States)

    Sahay, S; Hamid, B; Singh, P; Ranjan, K; Chauhan, D; Rana, R S; Chaurse, V K

    2013-08-01

    Of the twenty-three morphotypes of yeasts isolated from soil capable of utilizing pectin as sole carbon source at 6°C, two yeast isolates, one psychrotolerant (PT1) and one psychrophilic (SPY11), were selected according to their ability to secrete pectinolytic enzymes under some oenological conditions (temperature 6 and 12°C and pH 3.5) and ability or inability to grow above 20°C, respectively. As compared to their optimal activity, the three pectinolytic enzymes viz., pectin methyl esterase (PME), endopolygalacturonase (endo-PG) and exopolygalacturonase (exo-PG) isolated and assayed at pH 3.5 from PT1 were found to retain 39, 60 and 60% activity at 12°C and 40, 79 and 74% activity at 28°C, respectively. Likewise, the enzymes PME and endo-PG at pH 3.5 from SPY11 displayed 46 and 86% activity at 12°C and 50 and 60% activity at 28°C, respectively. All these enzymes showed 20-90% of residual activity at pH 3.5 and 6°C. The yeast isolates PT1 and SPY11 were identified as Rhodotorula mucilaginosa and Cystofilobasidium capitatum, respectively, on the basis of morphological, physiological and molecular characteristics. This study presents the first report on pectinolytic activities under major oenological conditions from psychrotolerant isolate R. mucilaginosa PT1 and psychrophilic isolate C. capitatum SPY11. The cold-active pectinolytic enzymes (PME, endo-PG and exo-PG) from the newly isolated and identified psychrophilic yeast Cystofilobasidium capitatum SPY11 and psychrotolerant yeast Rhodotorula mucilaginosa PT1that exhibited 50-80% of their optimum activity under some major oenological conditions pH (3.5) and temperatures (6 and 12°C) could be applied to wine production and juice clarification at low temperature. The psychrotrophic yeasts themselves could be applied to cold process for the production of enzymes thus saving cost of energy and protecting process from contamination. © 2013 The Society for Applied Microbiology.

  14. Antifungal activity of lectins against yeast of vaginal secretion

    Directory of Open Access Journals (Sweden)

    Bruno Severo Gomes

    2012-06-01

    Full Text Available Lectins are carbohydrate-binding proteins of non-imune origin. This group of proteins is distributed widely in nature and they have been found in viruses, microorganisms, plants and animals. Lectins of plants have been isolated and characterized according to their chemical, physical-chemical, structural and biological properties. Among their biological activities, we can stress its fungicidal action. It has been previously described the effect of the lectins Dviol, DRL, ConBr and LSL obtained from the seeds of leguminous plants on the growth of yeasts isolated from vaginal secretions. In the present work the experiments were carried out in microtiter plates and the results interpreted by both methods: visual observations and a microplate reader at 530nm. The lectin concentrations varied from 0.5 to 256µg/mL, and the inoculum was established between 65-70% of trammitance. All yeast samples isolated from vaginal secretion were evaluated taxonomically, where were observed macroscopic and microscopic characteristics to each species. The LSL lectin did not demonstrate any antifungal activity to any isolate studied. The other lectins DRL, ConBr and DvioL, showed antifungal potential against yeast isolated from vaginal secretion. These findings offering offer a promising field of investigation to develop new therapeutic strategies against vaginal yeast infections, collaborating to improve women's health.

  15. Engineering prokaryotic transcriptional activators as metabolite biosensors in yeast

    DEFF Research Database (Denmark)

    Skjødt, Mette Louise; Snoek, Tim; Kildegaard, Kanchana Rueksomtawin

    2016-01-01

    ,cis-muconic acid at different levels, and found that reporter gene output correlated with production. The transplantation of prokaryotic transcriptional activators into the eukaryotic chassis illustrates the potential of a hitherto untapped biosensor resource useful for biotechnological applications....... real-time monitoring of production has attracted attention. Here we applied systematic engineering of multiple parameters to search for a general biosensor design in the budding yeast Saccharomyces cerevisiae based on small-molecule binding transcriptional activators from the prokaryote superfamily...

  16. FERMENTATION ACTIVITY OF LACTOSE-FERMENTATION YEAST IN WHEY-MALT WORT

    Directory of Open Access Journals (Sweden)

    E. V. Greek

    2013-04-01

    Full Text Available The main parameters of fermentation of whey-malt wort with the use of different strains of lactose-fermentation yeast was investigated experimentally. According to the findings of investigation of fermentive activity for different types of lactose-fermentation microorganisms in whey-malt wort it was found that the most active spirituous fermentation for all parameters was in wort fermented by microorganisms Zygosaccharomyces lactis 868-K and Saccharomyces lactis 95. High capacity for utilization of malt carbohydrates represented by easily metabolized carbohydrates of malt extract was determined. Also organoleptic analysis of fermented whey drinks derived from the renewed mixtures of dry whey and fermented malt and yeast Zygosaccharomyces lactis 868-K and Saccharomyces lactis 95 was carried out. It was found that the drink fermented with yeast Zygosaccharomyces lactis 868-K had intense refreshing flavor of rye bread with fruit tones. Intensity growth of aromatization for complex of sample with microorganisms Saccharomyces lactis 95, indicating high organoleptic indexes of the drink was observed.

  17. The improvement of fermentation activity of yeast and mould by gamma irradiation on irradiated sago and onggok substrates

    International Nuclear Information System (INIS)

    Sjarief, Sri Hariani; Roselawati, M.L.

    1995-01-01

    For the purpose of increasing the product of fermentation and enzyme activity produced by microorganism, an experiment has been carried out using irradiated yeast and mould for fermenting irradiated sago (Metroxylon sago) and tapioca waste (onggok). Sago and onggok starches were irradiated with gamma-rays with a dose of 25 kGy. Onggok starch was irradiated on dried and wet conditions. Local isolated yeast and mould (R. oryza e) were irradiated in suspension with doses of 0.4 and 4 kGy. The measurement of enzymes activities such as amylase, AMG, cellulase and protease, and the fermentation products i.e. glucose and reductase d glucose were carried out for analyzing the influence of radiation on the fermentation process. The fermentation using yeast and onggok substrate produced glucose 28 % higher than sago. On the contrary, the fermentation of sago increased the production of reductase glucose by 7.3% higher than that of onggok. At the end of experiment, on the 14th. however, the activity of cellulase enzyme produced by irradiated mould in the fermentation with dried and wet onggok increase 13 to 15 times higher than the activity enzyme produced by the control. In a similar way fermentation of irradiated dry onggok produced amylase 57.9% higher than that on irradiated wet onggok. (author), 16 refs., 2 figs

  18. Screening of plant extracts for antimicrobial activity against bacteria and yeasts with dermatological relevance.

    Science.gov (United States)

    Weckesser, S; Engel, K; Simon-Haarhaus, B; Wittmer, A; Pelz, K; Schempp, C M

    2007-08-01

    There is cumulative resistance against antibiotics of many bacteria. Therefore, the development of new antiseptics and antimicrobial agents for the treatment of skin infections is of increasing interest. We have screened six plant extracts and isolated compounds for antimicrobial effects on bacteria and yeasts with dermatological relevance. The following plant extracts have been tested: Gentiana lutea, Harpagophytum procumbens, Boswellia serrata (dry extracts), Usnea barbata, Rosmarinus officinalis and Salvia officinalis (supercritical carbon dioxide [CO2] extracts). Additionally, the following characteristic plant substances were tested: usnic acid, carnosol, carnosic acid, ursolic acid, oleanolic acid, harpagoside, boswellic acid and gentiopicroside. The extracts and compounds were tested against 29 aerobic and anaerobic bacteria and yeasts in the agar dilution test. U. barbata-extract and usnic acid were the most active compounds, especially in anaerobic bacteria. Usnea CO2-extract effectively inhibited the growth of several Gram-positive bacteria like Staphylococcus aureus (including methicillin-resistant strains - MRSA), Propionibacterium acnes and Corynebacterium species. Growth of the dimorphic yeast Malassezia furfur was also inhibited by Usnea-extract. Besides the Usnea-extract, Rosmarinus-, Salvia-, Boswellia- and Harpagophytum-extracts proved to be effective against a panel of bacteria. It is concluded that due to their antimicrobial effects some of the plant extracts may be used for the topical treatment of skin disorders like acne vulgaris and seborrhoic eczema.

  19. Drying behaviour, effective diffusivity and energy of activation of olive leaves dried by microwave, vacuum and oven drying methods

    Science.gov (United States)

    Elhussein, Elaf Abdelillah Ali; Şahin, Selin

    2018-01-01

    Drying is the crucial food processing for bioactive components from plant materials before strating extraction in addition to preservation of raw plant materials during storage period. Olive leaves were dried by various methods such as microwave drying (MD), oven drying (OD) and vacuum drying (VD) at several temperature values in the present study. Mathematical models allow to develop, design and control the processes. 14 emprical equations were used to estimate the drying behaviour and the time required for drying. Convenience of the models were evaluated according to the correlation coefficient (R 2 ), varience (S 2 ) and root mean square deviation (D RMS ). On the other hand, the effective diffusion coefficient and energy for activation were also calculated. Effects of the drying methods on the total phenolic (TPC), flavonoid (TFC) and oleuropein contents and free radical scavenging activity (FRSA) of the olive leaves were also investigated to take into considiration the quality of the dried product. MD has proved to be the fastest drying method having the highest effective diffusivity and the lowest activation energy with a more qualitive product.

  20. The manometric determination of thiamine pyrophosphate and the inhibition of the acid yeast phosphatase

    NARCIS (Netherlands)

    Steyn-Parvé, Elizabeth P.

    1962-01-01

    Sodium molybdate is a powerful inhibitor of the acid yeast phosphatase in both fresh baker's yeast and dried brewer's yeast, provided that the yeast is suspended in a suitable buffer. It displays no action in citrate or phosphate buffers, but is active in acetate or maleate buffers, both at the

  1. ACTIVITY OF SUPEROXIDE DISMUTASE ENZYME IN YEAST SACCHAROMYCES CEREVISIAE

    Directory of Open Access Journals (Sweden)

    Blažena Lavová

    2014-02-01

    Full Text Available Reactive oxygen species (ROS with reactive nitrogen species (RNS are known to play dual role in biological systems, they can be harmful or beneficial to living systems. ROS can be important mediators of damage to cell structures, including proteins, lipids and nucleic acids termed as oxidative stress. The antioxidant enzymes protect the organism against the oxidative damage caused by active oxygen forms. The role of superoxide dismutase (SOD is to accelerate the dismutation of the toxic superoxide radical, produced during oxidative energy processes, to hydrogen peroxide and molecular oxygen. In this study, SOD activity of three yeast strains Saccharomyces cerevisiae was determined. It was found that SOD activity was the highest (23.7 U.mg-1 protein in strain 612 after 28 hours of cultivation. The lowest SOD activity from all tested strains was found after 56 hours of cultivation of strain Gyöng (0.7 U.mg-1 protein.

  2. Bodipy-VAD-Fmk, a useful tool to study yeast peptide N-glycanase activity

    NARCIS (Netherlands)

    Witte, Martin D.; Descals, Carlos V.; Lavoir, Sebastiaan V.P. de; Florea, Bogdan I.; Marel, Gijsbert A. van der; Overkleeft, Herman S.

    2007-01-01

    In this paper the development of a fluorescent activity based probe, Bodipy-VAD-Fmk, for visualization of yeast peptide N-glycanase is described. The activity based probe is used to assess the efficacy of known and new chitobiose-based electrophilic traps to bind yeast peptide N-glycanase.

  3. Designing CAF-adjuvanted dry powder vaccines: Spray drying preserves the adjuvant activity of CAF01

    DEFF Research Database (Denmark)

    Ingvarsson, Pall Thor; Schmidt, Signe Tandrup; Christensen, Dennis

    2013-01-01

    spray drying. The optimal excipient to stabilize CAF01 during spray drying and for the design of nanocomposite microparticles was identified among mannitol, lactose and trehalose. Trehalose and lactose were promising stabilizers with respect to preserving liposome size, as compared to mannitol...... parameters suggested that a fast drying rate is essential to avoid phase separation and lipid accumulation at the surface of the microparticles during spray drying. Finally, immunization studies in mice with CAF01 in combination with the tuberculosis antigen Ag85B-ESAT6-Rv2660c (H56) demonstrated that spray...... drying of CAF01 with trehalose under optimal processing conditions resulted in the preservation of the adjuvant activity in vivo. These data demonstrate the importance of liposome stabilization via optimization of formulation and processing conditions in the engineering of dry powder liposome...

  4. Active role of a human genomic insert in replication of a yeast artificial chromosome.

    Science.gov (United States)

    van Brabant, A J; Fangman, W L; Brewer, B J

    1999-06-01

    Yeast artificial chromosomes (YACs) are a common tool for cloning eukaryotic DNA. The manner by which large pieces of foreign DNA are assimilated by yeast cells into a functional chromosome is poorly understood, as is the reason why some of them are stably maintained and some are not. We examined the replication of a stable YAC containing a 240-kb insert of DNA from the human T-cell receptor beta locus. The human insert contains multiple sites that serve as origins of replication. The activity of these origins appears to require the yeast ARS consensus sequence and, as with yeast origins, additional flanking sequences. In addition, the origins in the human insert exhibit a spacing, a range of activation efficiencies, and a variation in times of activation during S phase similar to those found for normal yeast chromosomes. We propose that an appropriate combination of replication origin density, activation times, and initiation efficiencies is necessary for the successful maintenance of YAC inserts.

  5. Chemical Synthesis of Sulfated Yeast (Saccharomyces cerevisiae) Glucans and Their In Vivo Antioxidant Activity.

    Science.gov (United States)

    Zhang, Hua; Zhang, Jing; Fan, Ziluan; Zhou, Xintao; Geng, Lin; Wang, Zhenyu; Regenstein, Joe M; Xia, Zhiqiang

    2017-07-28

    The effects of sulfation of yeast glucans was optimized using response surface methodology. The degree of sulfation was evaluated from 0.11 to 0.75 using ion-chromatography. The structural characteristics of SYG (sulfation of yeast glucans) with a DS = 0.75 were determined using high-performance liquid chromatography/gel-permeation chromatography and finally by Fourier transform infrared spectrometry. The SYG had lower viscosity and greater solubility than the native yeast glucans, suggesting that the conformation of the SYG had significantly changed. The results also showed that SYG had a significantly greater antioxidant activity in vivo compared to native yeast glucans.

  6. Use of two osmoethanol tolerant yeast strain to ferment must from Tempranillo dried grapes: effect on wine composition.

    Science.gov (United States)

    López de Lerma, N; Peinado, R A

    2011-01-31

    The must from Tempranillo dried grapes was divided into four batches to produce sweet wine. The first one was fortified with ethanol up to 12% (v/v) to avoid fermentation (traditional way). Other two batches were partially fermented with two osmoethanol tolerant Saccharomyces cerevisiae strains (X4 and X5). The last one was fermented with native yeast by spontaneous fermentation. Wines fermented partially with the strains X4 and X5 show high volatile acidity values (above 2g/L expressed as acetic acid), and a glycerol concentration around 20 g/L. Both strains also produce high amount of carboxylic acids and therefore the wines show a high ethyl ester concentration. Aromatic series were obtained for all the wines by grouping aroma compounds according to their odor descriptors. The series of the fermented wines with higher values in relation with the control wine were fruity, sweet and fatty, emphasizing the fruity series in the samples fermented with the X4 and X5 strains. The sensorial analysis of the wine samples by a tasting panel put in evidence that the musts fermented with the osmoethanol tolerant yeasts were better valued than the rest of the wine samples. The must fermented with the X4 strain obtained the maximum score in terms of aroma and flavour. So, the use of these osmoethanol tolerant S. cerevisiae strains could be a suitable alternative to produce sweet wines from must with high sugar concentration. The wines obtained this way are chemically and organoleptically more complex than those elaborated traditionally. Copyright © 2010 Elsevier B.V. All rights reserved.

  7. Extracellular enzymatic activities and physiological profiles of yeasts colonizing fruit trees.

    Science.gov (United States)

    Molnárová, Jana; Vadkertiová, Renáta; Stratilová, Eva

    2014-07-01

    Yeasts form a significant and diverse part of the phyllosphere microbiota. Some yeasts that inhabit plants have been found to exhibit extracellular enzymatic activities. The aim of the present study was to investigate the ability of yeasts isolated from leaves, fruits, and blossoms of fruit trees cultivated in Southwest Slovakia to produce extracellular enzymes, and to discover whether the yeasts originating from these plant organs differ from each other in their physiological properties. In total, 92 strains belonging to 29 different species were tested for: extracellular protease, β-glucosidase, lipase, and polygalacturonase activities; fermentation abilities; the assimilation of xylose, saccharose and alcohols (methanol, ethanol, glycerol); and for growth in a medium with 33% glucose. The black yeast Aureobasidium pullulans showed the largest spectrum of activities of all the species tested. Almost 70% of the strains tested demonstrated some enzymatic activity, and more than 90% utilized one of the carbon compounds tested. Intraspecies variations were found for the species of the genera Cryptococcus and Pseudozyma. Interspecies differences of strains exhibiting some enzymatic activities and utilizing alcohols were also noted. The largest proportion of the yeasts exhibited β-glucosidase activity and assimilated alcohols independently of their origin. The highest number of strains positive for all activities tested was found among the yeasts associated with leaves. Yeasts isolated from blossoms assimilated saccharose and D-xylose the most frequently of all the yeasts tested. The majority of the fruit-inhabiting yeasts grew in the medium with higher osmotic pressure. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. Proteolytic activities in yeast after UV irradiation. Pt. 2

    Energy Technology Data Exchange (ETDEWEB)

    Schwencke, J.; Moustacchi, E.

    1982-04-01

    When the levels of three common yeast proteinases in exponentially growing cells of mutants blocked in different repair pathways are compared to that of isogenic wild-type cells, it can be seen that the level of proteinase B is enhanced in the mutants whereas the levels of leucin aminopeptidase (Leu.AP) and lysine aminopeptidase (Lys.AP) are similar in all strains. As in its corresponding wild type, the level of proteinase B activity is further enhanced after UV-irradiation in a mutant blocked in excision-repair (rad1-3). In contrast, following the same treatment the level of proteinase B remains almost constant in a mutant blocked in a general error-prone repair system (rad6-1) and in a mutant defective in a more specific mutagenic repair pathway (pso2-1). Cycloheximide, an inhibitor of protein synthesis, blocks the post-UV enhancement in proteinase B activity observed in rad1-3 indicating that, as in the wild-type cells, an inducible process is involved. The levels of Lys.AP and Leu.AP are, respectively, either unaffected or only moderately increased following UV-treatment of the repair defective mutants, as in wild-type strains.

  9. Diversity and killer activity of yeasts in Malaysian fermented food samples.

    Science.gov (United States)

    Lim, S L; Tay, S T

    2011-08-01

    The biodiversity and the killer activity of yeasts isolated from various types of fermented food in Malaysia were investigated in this study. Of 252 yeasts isolated from 48 fermented food samples in this study, 19 yeast species were identified based on sequence analysis of the ITS1-5.8S-ITS2 partial fragments of the yeasts. A total of 29 (11.5%) of the yeast isolates demonstrated killer activity to at least one Candida species tested in this study; including 22 isolates of Trichosporon asahii, 4 isolates of Pichia anomala, and one isolate each of Pichia norvegensis, Pichia fermentans and Issatchenkia orientalis, respectively. The presence of killer yeasts reflects antagonism that occurs during microbial interaction in the fermented food, whereby certain yeasts produce killer toxins and possibly other toxic substances in competition for limited nutrients and space. The anti-Candida activity demonstrated by killer yeasts in this study should be further explored for development of alternative therapy against candidiasis.

  10. Cytolethal Distending Toxin Demonstrates Genotoxic Activity in a Yeast Model

    OpenAIRE

    Hassane, Duane C.; Lee, Robert B.; Mendenhall, Michael D.; Pickett, Carol L.

    2001-01-01

    Cytolethal distending toxins (CDTs) are multisubunit proteins produced by a variety of bacterial pathogens that cause enlargement, cell cycle arrest, and apoptosis in mammalian cells. While their function remains uncertain, recent studies suggest that they can act as intracellular DNases in mammalian cells. Here we establish a novel yeast model for understanding CDT-associated disease. Expression of the CdtB subunit in yeast causes a G2/M arrest, as seen in mammalian cells. CdtB toxicity is n...

  11. Hypoglycemic activity of dried extracts of Bauhinia forficata Link.

    Science.gov (United States)

    da Cunha, A M; Menon, S; Menon, R; Couto, A G; Bürger, C; Biavatti, M W

    2010-01-01

    Leaves of the pantropical genus Bauhinia (Fabaceae) are known popularly as cow's foot, due to their unique characteristic bilobed aspect. The species Bauhinia forficata (Brazilian Orchid-tree) is widely used in folk medicine as an antidiabetic. The present work investigates the hypoglycemic activity of the dried extracts of Bauhinia forficata leaves in vivo, as well as the influence of the drying and granulation processes on this activity. The fluid extract was dried to generate oven-dried (ODE), spray-dried (SDE) and wet granulation (WGE) extracts, with the aid of colloidal silicon dioxide and/or cellulose:lactose mixture. The dried extracts were characterized by spectrophotometric, chromatographic and photo microscopy image analysis. 200 mg/kg body wt., p.o. of each dried product were administered orally to male Wistar rats over 7 days old, for biomonitoring of the hypoglycemic activity profile. The effect of the extracts was studied in STZ-induced diabetic rats. After 7 days of treatment, fasting glucose was determined, and the livers were removed, dried on tissue paper, weighed, and stored at -20 degrees C to estimate hepatic glycogen. Our results show that spray-drying or oven-drying processes applied to B. forficata extracts did not significantly alter its flavonoid profile or its hypoglycemic activity. Indeed, the dried extracts of B. forficata act differently from glibenclamide. Despite the lower active content in WGE, because of the higher concentration of adjuvants, the use of the granulation process improved the manufacturing properties of the ODE, making this material more appropriate for use in tablets or capsules.

  12. A Dried Yeast Fermentate Prevents and Reduces Inflammation in Two Separate Experimental Immune Models

    Directory of Open Access Journals (Sweden)

    Malkanthi Evans

    2012-01-01

    Full Text Available Diverse and significant benefits against cold/flu symptoms and seasonal allergies have been observed with a dried fermentate (DF derived from Saccharomyces cerevisiae (EpiCor in multiple published randomized trials. To determine if DF may influence other immune conditions, two separate animal studies were conducted. Study 1 examined the ability of DF to prevent or reduce inflammation when given orally for 14 days to rats prior to receiving 1% carrageenan (localized inflammation model. DF significantly (P<0.05 reduced swelling at all time points (1, 2, 3, 6, 12, and 24 hours versus the control. Edema severity and PGE2 levels were reduced by approximately 50% and 25% (P<0.05, respectively. Study 2 examined the ability of DF to treat established inflammation induced by type-2 collagen in mice over 4 weeks (autoimmune arthritis model. Significantly reduced arthritis scores, antibody response to type-2 collagen, and interferon-gamma levels were observed compared to controls (all parameters P<0.05. DF favorably impacts multiple acute and potentially chronic immunologic inflammatory control mechanisms and should be further tested in clinical trials.

  13. The effect of supplementation with three commercial inactive dry yeasts on the colour, phenolic compounds, polysaccharides and astringency of a model wine solution and red wine.

    Science.gov (United States)

    González-Royo, Elena; Esteruelas, Mireia; Kontoudakis, Nikolaos; Fort, Francesca; Canals, Joan Miquel; Zamora, Fernando

    2017-01-01

    Nowadays supplementing red wines with commercial inactive dry yeasts is a widespread practice in winemaking because it leads to better balanced wines through increased mouthfeel and smooth astringency. The aim of this article is to study, in a red wine and in a model wine solution, how supplementation with three commercial inactive dry yeasts affects chemical composition and astringency. This will give us a better understanding of the action mechanism involved. The results suggest that this action mechanism is related to two different phenomena. The first is that inactive yeasts release polysaccharides and oligosaccharides which can increase mouthfeel and inhibit interactions between salivary protein and tannins. The second is that they have a direct effect on the precipitation or absorption of proanthocyanidins, especially the larger polymers, which have been described as the most astringent. It can be concluded that supplementation with inactive yeasts is indeed a useful tool for smoothing the astringency of red wines. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

  14. Designing CAF-adjuvanted dry powder vaccines: spray drying preserves the adjuvant activity of CAF01.

    Science.gov (United States)

    Ingvarsson, Pall Thor; Schmidt, Signe Tandrup; Christensen, Dennis; Larsen, Niels Bent; Hinrichs, Wouter Leonardus Joseph; Andersen, Peter; Rantanen, Jukka; Nielsen, Hanne Mørck; Yang, Mingshi; Foged, Camilla

    2013-05-10

    Dry powder vaccine formulations are highly attractive due to improved storage stability and the possibility for particle engineering, as compared to liquid formulations. However, a prerequisite for formulating vaccines into dry formulations is that their physicochemical and adjuvant properties remain unchanged upon rehydration. Thus, we have identified and optimized the parameters of importance for the design of a spray dried powder formulation of the cationic liposomal adjuvant formulation 01 (CAF01) composed of dimethyldioctadecylammonium (DDA) bromide and trehalose 6,6'-dibehenate (TDB) via spray drying. The optimal excipient to stabilize CAF01 during spray drying and for the design of nanocomposite microparticles was identified among mannitol, lactose and trehalose. Trehalose and lactose were promising stabilizers with respect to preserving liposome size, as compared to mannitol. Trehalose and lactose were in the glassy state upon co-spray drying with the liposomes, whereas mannitol appeared crystalline, suggesting that the ability of the stabilizer to form a glassy matrix around the liposomes is one of the prerequisites for stabilization. Systematic studies on the effect of process parameters suggested that a fast drying rate is essential to avoid phase separation and lipid accumulation at the surface of the microparticles during spray drying. Finally, immunization studies in mice with CAF01 in combination with the tuberculosis antigen Ag85B-ESAT6-Rv2660c (H56) demonstrated that spray drying of CAF01 with trehalose under optimal processing conditions resulted in the preservation of the adjuvant activity in vivo. These data demonstrate the importance of liposome stabilization via optimization of formulation and processing conditions in the engineering of dry powder liposome formulations. Copyright © 2013 Elsevier B.V. All rights reserved.

  15. Yeast enolase: mechanism of activation by metal ions.

    Science.gov (United States)

    Brewer, J M

    1981-01-01

    Yeast enolase as prepared by current procedures is inherently chemically homogeneous, though deamidation and partial denaturation can produce electrophoretically distinct forms. A true isozyme of the enzyme exists but does not survive the purification procedure. The chemical sequence for both has been established. The enzyme behaves in solution like a compact, nearly spherical molecule of moderate hydration. Strong intramolecular forces maintain the structure of the individual subunits. The enzyme as isolated is dimeric. If dissociated in the presence of magnesium ions and substrate, then the subunits are active, but if the dissociation occurs in the absence of metal ions, they are inactive until they have reassociated and undergone a first order "annealing" process. Magnesium (II) enhances association. The interaction between the subunits is hydrophobic in character. The enzyme can bind up to 2 mol of most metal ions in "conformational" sites which then allows up to 2 mol of substrate or some substrate analogue to bind. This is not sufficient for catalysis, but conformational metal ions do more than just allow substrate binding. A change in the environment of the metal ions occurs on substrate or substrate analogue binding. There is an absolute correlation between the occurrence of a structural change undergone by the 3-amino analogue of phosphoenolpyruvate and whether the metal ions produce any level of enzymatic activity. For catalysis, two more moles of metal ions, called "catalytic", must bind. There is evidence that the enzymatic reaction involves a carbanion mechanism. It is likely that two more moles of metal ion can bind which inhibit the reaction. The requirement for 2 mol of metal ion per subunit which contribute in different ways to catalysis is exhibited by a number of other enzymes.

  16. Potential of yeasts isolated from dry-cured ham to control ochratoxin A production in meat models.

    Science.gov (United States)

    Peromingo, Belén; Núñez, Félix; Rodríguez, Alicia; Alía, Alberto; Andrade, María J

    2018-03-02

    The environmental conditions reached during the ripening of dry-cured meat products favour the proliferation of moulds on their surface. Some of these moulds are hazardous to consumers because of their ability to produce ochratoxin A (OTA). Biocontrol using Debaryomyces hansenii could be a suitable strategy to prevent the growth of ochratoxigenic moulds and OTA accumulation in dry-cured meat products. The aim of this work was to evaluate the ability of two strains of D. hansenii to control the growth and OTA production of Penicillium verrucosum in a meat model under water activities (a w ) values commonly reached during the dry-cured meat product ripening. The presence of D. hansenii strains triggered a lengthening of the lag phase and a decrease of the growth rate of P. verrucosum in meat-based media at 0.97 and 0.92 a w . Both D. hansenii strains significantly reduced OTA production (between 85.16 and 92.63%) by P. verrucosum in the meat-based medium at 0.92 a w . Neither absorption nor detoxification of OTA by D. hansenii strains seems to be involved. However, a repression of the expression of the non-ribosomal peptide synthetase (otanpsPN) gene linked to the OTA biosynthetic pathway was observed in the presence of D. hansenii. To confirm the protective role of D. hansenii strains, they were inoculated together with P. verrucosum Pv45 in dry-fermented sausage and dry-cured ham slices. Although P. verrucosum Pv45 counts were not affected by the presence of D. hansenii in both meat matrices, a reduction of OTA amount was observed. Therefore, the effect of D. hansenii strains on OTA accumulation should be attributed to a reduction at transcriptional level. Consequently, native D. hansenii can be useful as biocontrol agent in dry-cured meat products for preventing the hazard associated with the presence of OTA. Copyright © 2018 Elsevier B.V. All rights reserved.

  17. Screening and evaluation of the glucoside hydrolase activity in Saccharomyces and Brettanomyces brewing yeasts.

    Science.gov (United States)

    Daenen, L; Saison, D; Sterckx, F; Delvaux, F R; Verachtert, H; Derdelinckx, G

    2008-02-01

    The aim of this study was to select and examine Saccharomyces and Brettanomyces brewing yeasts for hydrolase activity towards glycosidically bound volatile compounds. A screening for glucoside hydrolase activity of 58 brewing yeasts belonging to the genera Saccharomyces and Brettanomyces was performed. The studied Saccharomyces brewing yeasts did not show 1,4-beta-glucosidase activity, but a strain dependent beta-glucanase activity was observed. Some Brettanomyces species did show 1,4-beta-glucosidase activity. The highest constitutive activity was found in Brettanomyces custersii. For the most interesting strains the substrate specificity was studied and their activity was evaluated in fermentation experiments with added hop glycosides. Fermentations with Br. custersii led to the highest release of aglycones. Pronounced exo-beta-glucanase activity in Saccharomyces brewing yeasts leads to a higher release of certain aglycones. Certain Brettanomyces brewing yeasts, however, are more interesting for hydrolysis of glycosidically bound volatiles of hops. The release of flavour active compounds from hop glycosides opens perspectives for the bioflavouring and product diversification of beverages like beer. The release can be enhanced by using Saccharomyces strains with high exo-beta-glucanase activity. Higher activities can be found in Brettanomyces species with beta-glucosidase activity.

  18. A high-throughput method for quantifying metabolically active yeast cells

    DEFF Research Database (Denmark)

    Nandy, Subir Kumar; Knudsen, Peter Boldsen; Rosenkjær, Alexander

    2015-01-01

    By redesigning the established methylene blue reduction test for bacteria and yeast, we present a cheap and efficient methodology for quantitative physiology of eukaryotic cells applicable for high-throughput systems. Validation of themethod in fermenters and highthroughput systems proved....... The drop in metabolic activity associated with the diauxic shift in yeast proved more pronounced for the MBRT-derived curve compared with OD curves, consistent with a dramatic shift in the ratio between live and dead cells at this metabolic event. This method provides a tool with numerous applications, e.......g. characterizing the death phase of stationary phase cultures, or in drug screens with pathogenic yeasts....

  19. Improvement of nutritional quality and antioxidant activities of yeast ...

    African Journals Online (AJOL)

    African Journal of Biotechnology ... This study evaluated the potential use and improves the health beneficial properties of the soybean waste manufacturing products by solid-state fermentation of six GRAS ... Key words: Solid state fermentation, yeast, waste soybean manufacturing products, antioxidant, protein, fiber.

  20. Effect of electron-ion treatment on fermentative activity of food yeasts

    International Nuclear Information System (INIS)

    Sergeev, I.N.; Ostapenkov, A.M.

    1988-01-01

    Investigation into effect of electron-ion treatment (EIT) on fermentative activity (FA) of Sacch cerevisial type yeasts of 12 breed was conducted. It is shown that even within the limits of one and the same type different treatment regimes are meded. This is obviously connected with physiologic peculiarities of different yeast breeds. Therefore an individual optimal treatment regime should be determined in each particular case during EIT of different breeds

  1. Characterization of pectinase activity for enology from yeasts occurring in Argentine Bonarda grape

    Science.gov (United States)

    Merín, María Gabriela; Martín, María Carolina; Rantsiou, Kalliopi; Cocolin, Luca; de Ambrosini, Vilma Inés Morata

    2015-01-01

    Pectinolytic enzymes are greatly important in winemaking due to their ability to degrade pectic polymers from grape, contributing to enhance process efficiency and wine quality. This study aimed to analyze the occurrence of pectinolytic yeasts during spontaneous fermentation of Argentine Bonarda grape, to select yeasts that produce extracellular pectinases and to characterize their pectinolytic activity under wine-like conditions. Isolated yeasts were grouped using PCR-DGGE and identified by partial sequencing of 26S rRNA gene. Isolates comprised 7 genera, with Aureobasidium pullulans as the most predominant pectinolytic species, followed by Rhodotorula dairenensis and Cryptococcus saitoi. No pectinolytic activity was detected among ascomycetous yeasts isolated on grapes and during fermentation, suggesting a low occurrence of pectinolytic yeast species in wine fermentation ecosystem. This is the first study reporting R. dairenensis and Cr. saitoi species with pectinolytic activity. R. dairenensis GM-15 produced pectinases that proved to be highly active at grape pH, at 12 °C, and under ethanol and SO2 concentrations usually found in vinifications (pectinase activity around 1.1 U/mL). This strain also produced cellulase activity at 12 °C and pH 3.5, but did not produce β-glucosidase activity under these conditions. The strain showed encouraging enological properties for its potential use in low-temperature winemaking. PMID:26413065

  2. Compaction and packaging of dry active municipal wastes

    International Nuclear Information System (INIS)

    Chen Zongming; Xi Xinmin

    1994-01-01

    The authors present the feature of a compaction system for active municipal wastes and the radiological monitoring results of workplace and environment. A variety of dry active municipal wastes could be compacted by this system. Volume reduction factor attained to 5 to 7 for soft wastes and 8 to 13 for hard wastes. No evident radiological impact was found on workplace and environment

  3. Effect of menadione and hydrogen peroxide on catalase activity in Saccharomyces yeast strains

    Directory of Open Access Journals (Sweden)

    Nadejda EFREMOVA

    2013-05-01

    Full Text Available It has been studied the possibility of utilization of two important oxidant factors as regulators of catalase activity in Saccharomyces yeasts. In this paper results of the screening of some Saccharomyces yeast strains for potential producers of catalase are presented. Results of the screening for potential catalase producer have revealed that Saccharomyces cerevisiae CNMN-Y-11 strain possesses the highest catalase activity (2900 U/mg protein compared with other samples. Maximum increase of catalase activity with 50-60% compared to the reference sample was established in the case of hydrogen peroxide and menadione utilization in optimal concentrations of 15 and 10 mM. This research has been demonstrated the potential benefits of application of hydrogen peroxide and menadione as stimulatory factors of catalase activity in Saccharomyces yeasts.

  4. Genetic diversity and pectinolytic activity of epiphytic yeasts from grape carposphere.

    Science.gov (United States)

    Filho, M Cilião; Bertéli, M B D; Valle, J S; Paccola-Meirelles, L D; Linde, G A; Barcellos, F G; Colauto, N B

    2017-06-20

    The genetic diversity of epiphytic yeasts from grape carposphere is susceptible to environmental variations that determine the predominant carposphere microbiota. Understanding the diversity of yeasts that inhabit grape carposphere in different environments and their pectinolytic activity is a way to understand the biotechnological potential that surrounds us and help improve winemaking. Therefore, this study aimed to evaluate the pectinolytic activity and characterize the genetic diversity of isolated epiphytic yeasts from grape carposphere. Grapes of the Bordeaux cultivar were collected from different regions of Paraná and Rio Grande do Sul States, in Brazil, and the yeasts were isolated from these grape carpospheres. Monosporic isolates were morphologically and genetically characterized on potato dextrose agar medium and by PCR-RFLP and rep-PCR (BOX-PCR) in the ITS1-5.8S-ITS2 region of rDNA. The index of pectinolytic activity of isolates was also evaluated estimating the ratio between the halo diameter of enzymatic degradation and the diameter of the colony when the isolates were grown in cultivation medium containing 10 g/L pectin, 5 g/L yeast extract, 15 g/L agar, 0.12% (w/v) Congo red, and pH 6.2. We observed that the grape carposphere is an environment with a great genetic diversity of epiphytic yeasts of the following genera: Cryptococcus (31.25%), Pichia (25.0%), Candida (25.0%), Dekkera (12.5%), and Saccharomyces (6.25%). The PCR-RFLP technique allowed analyzing existing polymorphism among individuals of a population based on a more restrict and evolutionarily preserved region, mostly utilized to differentiate isolates at the genus level. Approximately 33% of yeast isolates presented pectinolytic activity with potential biotechnological for wine and fruit juice production. This great genetic variability found indicated that it is a potential reservoir of genes to be applied in viniculture improvement programs.

  5. The diversity, extracellular enzymatic activities and photoprotective compounds of yeasts isolated in Antarctica

    Directory of Open Access Journals (Sweden)

    Aline B. M Vaz

    2011-09-01

    Full Text Available The diversity of yeasts collected from different sites in Antarctica (Admiralty Bay, King George Island and Port Foster Bay and Deception Island and their ability to produce extracellular enzymes and mycosporines were studied. Samples were collected during the austral summer season, between November 2006 and January 2007, from the rhizosphere of Deschampsia antarctica, ornithogenic (penguin guano soil, soil, marine and lake sediments, marine water and freshwater from lakes. A total of 89 isolates belonging to the following genera were recovered: Bensingtonia, Candida, Cryptococcus, Debaryomyces, Dioszegia, Exophiala, Filobasidium, Issatchenkia (Pichia, Kodamaea, Leucosporidium, Leucosporidiella, Metschnikowia, Nadsonia, Pichia, Rhodotorula, and Sporidiobolus, and the yeast-like fungi Aureobasidium, Leuconeurospora and Microglossum. Cryptococcus victoriae was the most frequently identified species. Several species isolated in our study have been previously reported to be Antarctic psychophilic yeasts, including Cr. antarcticus, Cr. victoriae, Dioszegia hungarica and Leucosporidium scottii. The cosmopolitan yeast species A. pullulans, C. zeylanoides, D. hansenii, I. orientalis, K. ohmeri, P. guilliermondii, Rh. mucilaginosa, and S. salmonicolor were also isolated. Five possible new species were identified. Sixty percent of the yeasts had at least one detectable extracellular enzymatic activity. Cryptococcus antarcticus, D. aurantiaca, D. crocea, D. hungarica, Dioszegia sp., E. xenobiotica, Rh. glaciales, Rh. laryngis, Microglossum sp. 1 and Microglossum sp. 2 produced mycosporines. Of the yeast isolates, 41.7% produced pigments and/or mycosporines and could be considered adapted to survive in Antarctica. Most of the yeasts had extracellular enzymatic activities at 4ºC and 20ºC, indicating that they could be metabolically active in the sampled substrates.

  6. Influence of yeast macromolecules on sweetness in dry wines: role of the saccharomyces cerevisiae protein Hsp12.

    Science.gov (United States)

    Marchal, Axel; Marullo, Philippe; Moine, Virginie; Dubourdieu, Denis

    2011-03-09

    Yeast autolysis during lees contact influences the organoleptic properties of wines especially by increasing their sweet taste. Although observed by winemakers, this phenomenon is poorly explained in enology. Moreover, the compounds responsible for sweetness in wine remain unidentified. This work provides new insights in this way by combining sensorial, biochemical and genetic approaches. First, we verified by sensory analysis that yeast autolysis in red wine has a significant effect on sweetness. Moderate additions of ethanol or glycerol did not have the same effect. Second, a sapid fraction was isolated from lees extracts by successive ultrafiltrations and HPLC purifications. Using nano-LC-MS/MS, peptides released by the yeast heat shock protein Hsp12p were distinctly identified in this sample. Third, we confirmed the sweet contribution of this protein by sensorial comparison of red wines incubated with two kinds of yeast strains: a wild-type strain containing the native Hsp12p and a deletion mutant strain that lacks the Hsp12p protein (Δ°HSP12 strain). Red wines incubated with wild-type strain showed a significantly higher sweetness than control wines incubated with Δ°HSP12 strains. These results demonstrated the contribution of protein Hsp12p in the sweet perception consecutive to yeast autolysis in wine.

  7. The euryhaline yeast Debaryomyces hansenii has two catalase genes encoding enzymes with differential activity profile.

    Science.gov (United States)

    Segal-Kischinevzky, Claudia; Rodarte-Murguía, Beatriz; Valdés-López, Victor; Mendoza-Hernández, Guillermo; González, Alicia; Alba-Lois, Luisa

    2011-03-01

    Debaryomyces hansenii is a spoilage yeast able to grow in a variety of ecological niches, from seawater to dairy products. Results presented in this article show that (i) D. hansenii has an inherent resistance to H2O2 which could be attributed to the fact that this yeast has a basal catalase activity which is several-fold higher than that observed in Saccharomyces cerevisiae under the same culture conditions, (ii) D. hansenii has two genes (DhCTA1 and DhCTT1) encoding two catalase isozymes with a differential enzymatic activity profile which is not strictly correlated with a differential expression profile of the encoding genes.

  8. Regulation of the yeast metabolic cycle by transcription factors with periodic activities

    Directory of Open Access Journals (Sweden)

    Pellegrini Matteo

    2011-10-01

    Full Text Available Abstract Background When growing budding yeast under continuous, nutrient-limited conditions, over half of yeast genes exhibit periodic expression patterns. Periodicity can also be observed in respiration, in the timing of cell division, as well as in various metabolite levels. Knowing the transcription factors involved in the yeast metabolic cycle is helpful for determining the cascade of regulatory events that cause these patterns. Results Transcription factor activities were estimated by linear regression using time series and genome-wide transcription factor binding data. Time-translation matrices were estimated using least squares and were used to model the interactions between the most significant transcription factors. The top transcription factors have functions involving respiration, cell cycle events, amino acid metabolism and glycolysis. Key regulators of transitions between phases of the yeast metabolic cycle appear to be Hap1, Hap4, Gcn4, Msn4, Swi6 and Adr1. Conclusions Analysis of the phases at which transcription factor activities peak supports previous findings suggesting that the various cellular functions occur during specific phases of the yeast metabolic cycle.

  9. 21 CFR 344.12 - Ear drying aid active ingredient.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 5 2010-04-01 2010-04-01 false Ear drying aid active ingredient. 344.12 Section 344.12 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED... alcohol 95 percent in an anhydrous glycerin 5 percent base. [65 FR 48905, Aug. 10, 2000] ...

  10. Comparative Study of Antibacterial Activities of the Fresh and Dried ...

    African Journals Online (AJOL)

    The fresh and dried fruit extracts of Capsicum species were screened for antibacterial activities against Staph. aureus, S. typhi and B. subtilis using two assay methods. The filter disk and agar plate diffusion were the assay methods employed in the study. The results of the study revealed that the extracts obtained from the ...

  11. Physiological And Blood Biochemical Responses To Dried Live Yeast Plus Vitamin E As A Dietary Supplement To Bovine Baladi Calves Under Hot Summer Conditions

    International Nuclear Information System (INIS)

    ABDALLA, E.B.; EL-MASRY, K.A.; TEAMA, F.E.; EMARA, S.S.

    2009-01-01

    The experiment was designed to study the effect of supplemented dried live yeast (DLY) + vitamin E to the diet of growing calves under hot summer conditions in Egypt. Six bovine Baladi calves with 115 kg initial body weight and 8-10 months old were used during two periods. In the first period, the calves were offered the concentrated basal diet only for one month and considered as a control period. In the second period, the calves were fed the same basal diet which supplemented with 15 g dried live yeast (Saccharomyces cerevisiae) + 600 IU vitamin E (alpha- tocopherol) per calf daily for one month and considered as a treated period. Body weight was recorded at the beginning and the end of each period, and daily gain was calculated for each animal. Blood samples were collected from each animal at the end of each period to determine some blood biochemical parameters and T 3 and T 4 concentrations as well as some immunological indices.The results showed that supplementation of DLY + 600 IU vitamin E to the diet of calves reduced significantly (P 3 and T 4 levels and improved feed efficiency and daily gain. It is concluded that supplementation of growing calves with 15 g DLY + 600 IU vitamin E / calf / day under Egyptian hot summer conditions reduced the effect of heat stress as shown by a decline in RT and modified most blood constituents and thyroid function which leads to an improvement in growing calves

  12. Design, Engineering, and Characterization of Prokaryotic Ligand-Binding Transcriptional Activators as Biosensors in Yeast

    DEFF Research Database (Denmark)

    Ambri, Francesca; Snoek, Tim; Skjødt, Mette Louise

    2018-01-01

    process. In the yeast Saccharomyces cerevisiae, implementation of allosterically regulated transcription factors from prokaryotes as metabolite biosensors has proven a valuable strategy to alleviate this screening bottleneck. Here, we present a protocol to select and incorporate prokaryotic...... transcriptional activators as metabolite biosensors in S. cerevisiae. As an example, we outline the engineering and characterization of the LysR-type transcriptional regulator (LTTR) family member BenM from Acetinobacter sp. ADP1 for monitoring accumulation of cis,cis-muconic acid, a bioplast precursor, in yeast...

  13. Proteases and caspase-like activity in the yeast Saccharomyces cerevisiae.

    Science.gov (United States)

    Wilkinson, Derek; Ramsdale, Mark

    2011-10-01

    A variety of proteases have been implicated in yeast PCD (programmed cell death) including the metacaspase Mca1 and the separase Esp1, the HtrA-like serine protease Nma111, the cathepsin-like serine carboxypeptideases and a range of vacuolar proteases. Proteasomal activity is also shown to have an important role in determining cell fate, with both pro- and anti-apoptotic roles. Caspase 3-, 6- and 8-like activities are detected upon stimulation of yeast PCD, but not all of this activity is associated with Mca1, implicating other proteases with caspase-like activity in the yeast cell death response. Global proteolytic events that accompany PCD are discussed alongside a consideration of the conservation of the death-related degradome (both at the level of substrate choice and cleavage site). The importance of both gain-of-function changes in the degradome as well as loss-of-function changes are highlighted. Better understanding of both death-related proteases and their substrates may facilitate the design of future antifungal drugs or the manipulation of industrial yeasts for commercial exploitation.

  14. The effects of an active live yeast product on the growth performance ...

    African Journals Online (AJOL)

    A study was conducted to evaluate the effects of a rumen-specific, active live yeast (Saccharomyces cerevisiae; SC CNCM I-1077), alone or in combination with an ionophore (lasalocid-Na) in standard feedlot diets, on production performance and carcass quality of lambs. Sixty South African (S.A.) Mutton Merino lambs, ...

  15. Enzyme Activities in Oleaginous Yeasts Accumulating and Utilizing Exogenous or Endogenous Lipids

    NARCIS (Netherlands)

    Holdsworth, Jane E.; Veenhuis, Marten; Ratledge, Colin

    1988-01-01

    The activities of ATP:citrate lyase (ACL; EC 4.1.3.8), carnitine acetyltransferase (CAT; EC 2.3.1.7), NADP+-dependent isocitrate dehydrogenase (ICDH; EC 1.1.1.42), isocitrate lyase (ICL; EC 4.1.3.1) and malic enzyme (malate dehydrogenase; EC 1.1.1.40) were measured in four oleaginous yeasts, Candida

  16. Regulation of activity of the yeast TATA-binding protein through intra ...

    Indian Academy of Sciences (India)

    Unknown

    Abbreviations used: BMH, Bismaleimidohexane; TBP, TATA-binding protein; yTBP, yeast TBP. J. Biosci. | Vol. ... Therefore for full-length TBP, intra-molecular interactions can regulate its activity via a similar ..... simulations (Miaskeiwicz and Ornstein 1996). .... box binding protein (TBP): A molecular dynamics computa-.

  17. Effect of dietary supplementation with selenium-enriched yeast or sodium selenite on ruminal enzyme activities and blood chemistry in sheep

    Directory of Open Access Journals (Sweden)

    Zita Faixová

    2016-01-01

    Full Text Available The experiment was conducted to evaluate the effect of feeding a diet supplemented with different forms of selenium on the rumen fluid, blood and serum enzyme activity and osmotic fragility of red blood cells in sheep. The experiment was carried out on 18 sheep of the Valashka breed at the age of 18 months, divided into 3 groups. The first group was given basal diet (BD with a Se content of 0.17 mg/kg of dry matter (DM. The second group received BD supplemented with 0.4 mg Se/kg of (DM in the form of sodium selenite. The third group received BD supplemented with 0.4 mg Se/kg of (DM in the form of Se-yeast extract. Duration of the trial was 12 weeks. Selenium concentration in blood and total rumen fluid were elevated in both supplemented groups with the highest values in Se-yeast-treated sheep. Blood glutathione peroxidase (GPx activity was significantly increased, regardless of the source of selenium. Osmotic resistance of red blood cells was not affected by selenium supplementation. The results indicate that feeding a diet supplemented with selenium from Se-yeast or selenite improved selenium status in blood and total rumen fluid. Selenium from sodium selenite was as effective as selenium from Se-yeast in the availability of selenium for the blood GPx activity. The effect of selenium supplementation on the ruminal enzyme activity depends on the selenium form; GGT and GDH were significantly higher in the Se-yeast supplement group, AST and ALP were significantly higher in the selenite supplement group.

  18. Cinética de produção de levedura seca em leito de jorro Production kinetics of dry yeast in spouted bed

    Directory of Open Access Journals (Sweden)

    Ana P. T. Rocha

    2008-02-01

    Full Text Available Estudou-se neste trabalho, a cinética de produção durante a secagem em um secador de leito de jorro convencional com inertes, trabalhando-se com alimentação intermitente de levedura, com umidade inicial de 70% em base úmida. Fez-se um planejamento fatorial 22 mais configuração estrela com 3 experimentos no ponto central, totalizando 11 experimentos, objetivando-se o estudo da influência da concentração de levedura e velocidade do ar na entrada sobre a cinética de produção de levedura seca. A cinética se mostrou crescente e praticamente linear em todos os experimentos. Esta análise permitiu a identificação das condições ideais de operação do secador com relação à velocidade de operação e de quantidade de levedura a ser alimentada para obtenção de um produto de qualidade para utilização como complemento protéico na alimentação de animais.In this study the production kinetics are studied during drying in a conventional spouted bed drier, with inert particles, working at intermittent feeding of yeast, with initial moisture content of 70% (wet basis. In order to study the influence of the yeast concentration and the input air speed on the production kinetics of dry yeast, a series of 11 experiments according to a factorial design 22 plus a star configuration, with 3 experiments in the central point, was done. It was found that the increasing kinetics was practically linear in all the experiments. From this analysis, optimal operational conditions were found for the drier input air velocity and amount of yeast to be loaded. The attainment of a quality product to be used as a protein complement for animal feeding was also considered.

  19. Yeasts preservation: alternatives for lyophilisation

    NARCIS (Netherlands)

    Nyanga, L.K.; Nout, M.J.R.; Smid, E.J.; Boekhout, T.; Zwietering, M.H.

    2012-01-01

    The aim of the study was to compare the effect of two low-cost, low technology traditional methods for drying starter cultures with standard lyophilisation. Lyophilised yeast cultures and yeast cultures preserved in dry rice cakes and dry plant fibre strands were examined for viable cell counts

  20. Antifungal Activity of Brazilian Propolis Microparticles against Yeasts Isolated from Vulvovaginal Candidiasis

    Directory of Open Access Journals (Sweden)

    Kelen Fátima Dalben Dota

    2011-01-01

    Full Text Available Propolis, a resinous compound produced by Apis mellifera L. bees, is known to possess a variety of biological activities and is applied in the therapy of various infectious diseases. The aim of this study was to evaluate the in vitro antifungal activity of propolis ethanol extract (PE and propolis microparticles (PMs obtained from a sample of Brazilian propolis against clinical yeast isolates of importance in the vulvovaginal candidiasis (VVC. PE was used to prepare the microparticles. Yeast isolates (n=89, obtained from vaginal exudates of patients with VVC, were exposed to the PE and the PMs. Moreover, the main antifungal drugs used in the treatment of VVC (Fluconazole, Voriconazole, Itraconazole, Ketoconazole, Miconazole and Amphotericin B were also tested. Minimum inhibitory concentration (MIC was determined according to the standard broth microdilution method. Some Candida albicans isolates showed resistance or dose-dependent susceptibility for the azolic drugs and Amphotericin B. Non-C. albicans isolates showed more resistance and dose-dependent susceptibility for the azolic drugs than C. albicans. However, all of them were sensitive or dose-dependent susceptible for Amphotericin B. All yeasts were inhibited by PE and PMs, with small variation, independent of the species of yeast. The overall results provided important information for the potential application of PMs in the therapy of VVC and the possible prevention of the occurrence of new symptomatic episodes.

  1. Caspase inhibitors of the P35 family are more active when purified from yeast than bacteria.

    Directory of Open Access Journals (Sweden)

    Ingo L Brand

    Full Text Available Many insect viruses express caspase inhibitors of the P35 superfamily, which prevent defensive host apoptosis to enable viral propagation. The prototypical P35 family member, AcP35 from Autographa californica M nucleopolyhedrovirus, has been extensively studied. Bacterially purified AcP35 has been previously shown to inhibit caspases from insect, mammalian and nematode species. This inhibition occurs via a pseudosubstrate mechanism involving caspase-mediated cleavage of a "reactive site loop" within the P35 protein, which ultimately leaves cleaved P35 covalently bound to the caspase's active site. We observed that AcP35 purifed from Saccharomyces cerevisae inhibited caspase activity more efficiently than AcP35 purified from Escherichia coli. This differential potency was more dramatic for another P35 family member, MaviP35, which inhibited human caspase 3 almost 300-fold more potently when purified from yeast than bacteria. Biophysical assays revealed that MaviP35 proteins produced in bacteria and yeast had similar primary and secondary structures. However, bacterially produced MaviP35 possessed greater thermal stability and propensity to form higher order oligomers than its counterpart purified from yeast. Caspase 3 could process yeast-purified MaviP35, but failed to detectably cleave bacterially purified MaviP35. These data suggest that bacterially produced P35 proteins adopt subtly different conformations from their yeast-expressed counterparts, which hinder caspase access to the reactive site loop to reduce the potency of caspase inhibition, and promote aggregation. These data highlight the differential caspase inhibition by recombinant P35 proteins purified from different sources, and caution that analyses of bacterially produced P35 family members (and perhaps other types of proteins may underestimate their activity.

  2. In vitro anidulafungin activity against yeasts – system and disseminated mycosis pathogens

    Directory of Open Access Journals (Sweden)

    A. B. Kulko

    2015-01-01

    Full Text Available We analyzed susceptibility to anidulafungin of yeasts clinical strains of Candida (14 species, Cryptococcus (1 species, Geotrichum (1 species, Rhodotorula (1 species and Saccharomyces (1 species. We revealed high anidulafungin activity against Candida spp., both common species and rare pathogens of candidiasis. It was found that over 99 % of Candida strains do not have an acquired resistance mechanisms to anidulafungin (microbiological criteria. The anidulafungin is not active against strains of Cryptococcus neoformans and Rhodotorula mucilaginosa.

  3. Quality and Antioxidant Activity of Buckwheat-Based Cookies Designed for a Raw Food Vegan Diet as Affected by Moderate Drying Temperature.

    Science.gov (United States)

    Brožková, Iveta; Dvořáková, Veronika; Michálková, Kateřina; Červenka, Libor; Velichová, Helena

    2016-12-01

    Buckwheat cookies with various ingredients for raw food vegan diet are usually prepared by soaking them in water at ambient temperature followed by drying at moderate temperature. The aim of this study was to examine the temperature effect on the microbiological quality, antioxidant properties and oxidative stability of lipids of final dried samples. The mixture of ingredients was soaked for 20 h in distilled water, and then cookies were formed and dried in air-forced oven at constant temperature in the range from 40 to 60 °C. Total viable counts, fungi, yeasts, coliform and aerobic spore-forming bacteria counts were evaluated in dried samples and were found to decrease during drying at 50 and 60 °C. Antioxidant activity was determined by DPPH and ABTS assays, and the former showed the highest value at 40 °C. Superoxide dismutase activity was also higher at 40 °C in comparison with that at 60 °C. The percentage of lipid peroxidation inhibition increased with the increase in drying temperature until 4th day of incubation. While peroxide value was significantly higher in samples dried at 40 °C, TBARS values did not show significant changes during the drying process. The results of this study suggest that drying buckwheat-based cookies at 40 °C retained their good antioxidant properties but represent a potentially serious microbial hazard.

  4. Fructanase and fructosyltransferase activity of non-Saccharomyces yeasts isolated from fermenting musts of Mezcal.

    Science.gov (United States)

    Arrizon, Javier; Morel, Sandrine; Gschaedler, Anne; Monsan, Pierre

    2012-04-01

    Fructanase and fructosyltransferase are interesting for the tequila process and prebiotics production (functional food industry). In this study, one hundred thirty non-Saccharomyces yeasts isolated from "Mezcal de Oaxaca" were screened for fructanase and fructosyltransferase activity. On solid medium, fifty isolates grew on Agave tequilana fructans (ATF), inulin or levan. In liquid media, inulin and ATF induced fructanase activities of between 0.02 and 0.27U/ml depending of yeast isolate. High fructanase activity on sucrose was observed for Kluyveromyces marxianus and Torulaspora delbrueckii, while the highest fructanase activity on inulin and ATF was observed for Issatchenkia orientalis, Cryptococcus albidus, and Candida apicola. Zygosaccharomyces bisporus and Candida boidinii had a high hydrolytic activity on levan. Sixteen yeasts belonging to K. marxianus, T. delbrueckii and C. apicola species were positive for fructosyltransferase activity. Mezcal microbiota proved to showed to be a source for new fructanase and fructosyltransferases with potential application in the tequila and food industry. Copyright © 2012 Elsevier Ltd. All rights reserved.

  5. Pyruvate Decarboxylase Activity Assay in situ of Different Industrial Yeast Strains

    Directory of Open Access Journals (Sweden)

    Dorota Kręgiel

    2009-01-01

    Full Text Available Cytoplasmic pyruvate decarboxylase (PDC, EC 4.1.1.1 is one of the key enzymes of yeast fermentative metabolism. PDC is the first enzyme which, under anaerobic conditions, leads to decarboxylation of pyruvate with acetaldehyde as the end product. The aim of this study is to develop a suitable method for PDC activity assay in situ for different industrial yeast strains. Saccharomyces sp. and Debaryomyces sp. yeast strains grew in fermentative medium with 12 % of glucose. Enzymatic assay was conducted in cell suspension treated with digitonin as permeabilisation agent, and with sodium pyruvate as a substrate, at temperature of 30 °C. Metabolites of PDC pathway were detected using gas chromatographic (GC technique. Various parameters like type and molar concentration of the substrate, minimal effective mass fraction of digitonin, cell concentration, reaction time and effect of pyrazole (alcohol dehydrogenase inhibitor were monitored to optimize PDC enzymatic assay in situ. In the concentration range of yeast cells from 1⋅10^7 to 1⋅10^8 per mL, linear correlation between the produced acetaldehyde and cell density was noticed. Only pyruvate was the specific substrate for pyruvate decarboxylase. In the presence of 0.05 M sodium pyruvate and 0.05 % digitonin, the enzymatic reaction was linear up to 20 min of the assay. During incubation, there was no formation of ethanol and, therefore, pyrazole was not necessary for the assay.

  6. Effect of increased yeast alcohol acetyltransferase activity on flavor profiles of wine and distillates.

    Science.gov (United States)

    Lilly, M; Lambrechts, M G; Pretorius, I S

    2000-02-01

    The distinctive flavor of wine, brandy, and other grape-derived alcoholic beverages is affected by many compounds, including esters produced during alcoholic fermentation. The characteristic fruity odors of the fermentation bouquet are primarily due to a mixture of hexyl acetate, ethyl caproate (apple-like aroma), iso-amyl acetate (banana-like aroma), ethyl caprylate (apple-like aroma), and 2-phenylethyl acetate (fruity, flowery flavor with a honey note). The objective of this study was to investigate the feasibility of improving the aroma of wine and distillates by overexpressing one of the endogenous yeast genes that controls acetate ester production during fermentation. The synthesis of acetate esters by the wine yeast Saccharomyces cerevisiae during fermentation is ascribed to at least three acetyltransferase activities, namely, alcohol acetyltransferase (AAT), ethanol acetyltransferase, and iso-amyl AAT. To investigate the effect of increased AAT activity on the sensory quality of Chenin blanc wines and distillates from Colombar base wines, we have overexpressed the alcohol acetyltransferase gene (ATF1) of S. cerevisiae. The ATF1 gene, located on chromosome XV, was cloned from a widely used commercial wine yeast strain of S. cerevisiae, VIN13, and placed under the control of the constitutive yeast phosphoglycerate kinase gene (PGK1) promoter and terminator. Chromoblot analysis confirmed the integration of the modified copy of ATF1 into the genome of three commercial wine yeast strains (VIN7, VIN13, and WE228). Northern blot analysis indicated constitutive expression of ATF1 at high levels in these yeast transformants. The levels of ethyl acetate, iso-amyl acetate, and 2-phenylethyl acetate increased 3- to 10-fold, 3.8- to 12-fold, and 2- to 10-fold, respectively, depending on the fermentation temperature, cultivar, and yeast strain used. The concentrations of ethyl caprate, ethyl caprylate, and hexyl acetate only showed minor changes, whereas the acetic acid

  7. Autoactivation of proteinase A initiates activation of yeast vacuolar zymogens

    DEFF Research Database (Denmark)

    van den Hazel, H B; Kielland-Brandt, Morten; Winther, Jakob R.

    1992-01-01

    The Saccharomyces cerevisiae PEP4 gene encodes proteinase A, an aspartyl protease. pep4 mutants are defective in the activation of many vacuolar hydrolases, including proteinase B. We have expressed a pep4 mutation which directs the accumulation of pro-proteinase A with a defective active site. Co...

  8. Evaluation of commercially available enzymes, probiotics, or yeast on apparent total-tract nutrient digestion and growth in nursery and finishing pigs fed diets containing corn dried distillers grains with solubles

    Science.gov (United States)

    The ability of enzymes, direct fed microbials, or yeast to enhance nutrient utilization or growth performance in nursery or finishing pigs fed diets containing increased levels of corn fiber from dried distillers grains with solubles (DDGS) is largely unknown. Ten commercially available feed additiv...

  9. Hybrid yeast strains capable of raising an extraordinarily broad range of dough types

    Energy Technology Data Exchange (ETDEWEB)

    Kowalski, S.; Zander, I.; Windisch, S.

    1981-01-01

    Over 200 hybrid yeast strains were screened and 11 of these found to have versatile fermentation characteristics. This paper reports the results obtained with these 11 strains compared with a commercially available strain of baker's yeast used for bread making and marketed as 'instant active dry yeast'. In contrast to bakers yeast, the hybrid strains fermented very well in yeast, hard biscuit, shortcake and heavy cake dough without prior sponge formation. The fermentation kinetics were investigated and the technical potential of such hybrid strains discussed on the basis of the fermentation kinetics.

  10. Enterovirus type 71 2A protease functions as a transcriptional activator in yeast

    Directory of Open Access Journals (Sweden)

    Lai Meng-Jiun

    2010-08-01

    Full Text Available Abstract Enterovirus type 71 (EV71 2A protease exhibited strong transcriptional activity in yeast cells. The transcriptional activity of 2A protease was independent of its protease activity. EV71 2A protease retained its transcriptional activity after truncation of 40 amino acids at the N-terminus but lost this activity after truncation of 60 amino acids at the N-terminus or deletion of 20 amino acids at the C-terminus. Thus, the acidic domain at the C-terminus of this protein is essential for its transcriptional activity. Indeed, deletion of amino acids from 146 to 149 (EAME in this acidic domain lost the transcriptional activity of EV71 2A protein though still retained its protease activity. EV71 2A protease was detected both in the cytoplasm and nucleus using confocal microscopy analysis. Coxsackie virus B3 2A protease also exhibited transcriptional activity in yeast cells. As expected, an acidic domain in the C-terminus of Coxsackie virus B3 2A protease was also identified. Truncation of this acidic domain resulted in the loss of transcriptional activity. Interestingly, this acidic region of poliovirus 2A protease is critical for viral RNA replication. The transcriptional activity of the EV71 or Coxsackie virus B3 2A protease should play a role in viral replication and/or pathogenesis.

  11. Comparative study of the antioxidant and immunomodulant activities between yeast and lab fermented papaya

    Directory of Open Access Journals (Sweden)

    Cristiana Caliceti

    2018-01-01

    Full Text Available Background: Dietary supplements of Carica papaya Linn fermented with yeast using a biotechnological process have well recognized positive effects on immunological, hematological, inflammatory, and oxidative stress parameters, utilized as biomarkers of chronic and degenerative diseases. Although many natural products fermented with lactic acid bacteria (LAB have shown beneficial effects on the immune system and on antioxidant defenses, formulations of papaya fermented with LAB have not yet been studied. Aims: The aims of this study were to investigate the immunomodulatory activity linked to the type of papaya fermentation (yeast vs LAB in macrophages and to evaluate whether the type of fermentation differently modulates oxidative stress both in cell free system and in a model of embryonic brain cells. Methods: Cytotoxicity was evaluated through cell proliferation kinetic and lactate dehydrogenase release assays; immunomodulatory activity through the transcriptional activation of inducible nitric oxide synthase (iNOS and Tumor Necrosis Factor α (TNFα by qRT-PCR in RAW 264.7 macrophages; antioxidant capacity was assessed, in cell free system and in pheochromocytoma cells embryonic brain cells, by measuring the intracellular ROS levels through a fluorescent dye. Results: Our data showed that all the formulations studied are safe at low concentrations (3-6 mg/ml; the LAB- fermented formulations promoted the expression of iNOS and TNFα more efficiently than yeast-fermented papaya preparation (p <0.001. In a cell free system, the LAB-fermented formulation acted as mild scavengers of ROS while, in cells, both formulations didn’t show any significant effect. Conclusions: This study corroborates previous reports showing the efficacy of yeast fermented papaya as a potent immunostimulant and highlights the beneficial contribution of lactic bacteria fermentation.

  12. Regulation of the Hsp104 middle domain activity is critical for yeast prion propagation.

    Directory of Open Access Journals (Sweden)

    Jennifer E Dulle

    Full Text Available Molecular chaperones play a significant role in preventing protein misfolding and aggregation. Indeed, some protein conformational disorders have been linked to changes in the chaperone network. Curiously, in yeast, chaperones also play a role in promoting prion maintenance and propagation. While many amyloidogenic proteins are associated with disease in mammals, yeast prion proteins, and their ability to undergo conformational conversion into a prion state, are proposed to play a functional role in yeast biology. The chaperone Hsp104, a AAA+ ATPase, is essential for yeast prion propagation. Hsp104 fragments large prion aggregates to generate a population of smaller oligomers that can more readily convert soluble monomer and be transmitted to daughter cells. Here, we show that the middle (M domain of Hsp104, and its mobility, plays an integral part in prion propagation. We generated and characterized mutations in the M-domain of Hsp104 that are predicted to stabilize either a repressed or de-repressed conformation of the M-domain (by analogy to ClpB in bacteria. We show that the predicted stabilization of the repressed conformation inhibits general chaperone activity. Mutation to the de-repressed conformation, however, has differential effects on ATP hydrolysis and disaggregation, suggesting that the M-domain is involved in coupling these two activities. Interestingly, we show that changes in the M-domain differentially affect the propagation of different variants of the [PSI+] and [RNQ+] prions, which indicates that some prion variants are more sensitive to changes in the M-domain mobility than others. Thus, we provide evidence that regulation of the M-domain of Hsp104 is critical for efficient prion propagation. This shows the importance of elucidating the function of the M-domain in order to understand the role of Hsp104 in the propagation of different prions and prion variants.

  13. Improvement in dry active waste segregation and processing

    International Nuclear Information System (INIS)

    Hillmer, T.P.; Anderson, K.D.; Dahlen, D.E.

    1989-01-01

    At the Palo Verde Nuclear Generating Station (PVNGS) the majority of dry active waste (DAW) volume reduction activities are performed in the site's new DAW processing and storage facility. This facility houses an interim storage area for a five year volume of compacted DAW, a shredder/compactor, and a DAW segregation area. The DAW segregation program locates and separates non-radioactive and reusable materials from DAW generated at the three unit PVNGS site. This program has saved more than 24,000 cubic feet of burial space and has reclaimed more than $1,000,000 worth of materials. Palo Verde has made numerous changes to the DAW segregation program since its inception. To ensure that the DAW segregation program remained cost effective and in compliance with applicable regulatory guidance, segregation techniques were revised and new equipment was evaluated and procured. This paper details that effort and summarizes the operational data that has been collected

  14. Effects of Drying Methods in Gaining of Extractive, Phenolic Content and Antioxidant Activity in Gynura Pseudochina (Lour.)

    OpenAIRE

    Rivai, Harrizul; Nurdin, Hazli; Suyani, Hamzar; Bakhtiar, Amri

    2010-01-01

    Effects of drying methods in gaining of extractive, phenolic content and antioxidant activity in Gynura pseudochina (Lour.) DC leaves have been investigated. The drying methods tested were air-drying at ± 25 oC, oven-drying at 40 OC, oven-drying at 60 OC, microwave oven-drying and fresh samples as control. Results revealed that drying of the fresh plant caused the decrease of extractive obtainability, phenolic content and antioxidant activity. There were significant differences among drying ...

  15. Active site - a site of binding of affinity inhibitors in baker's yeast inorganic pyrophosphatase

    International Nuclear Information System (INIS)

    Svyato, I.E.; Sklyankina, V.A.; Avaeva, S.M.

    1986-01-01

    The interaction of the enzyme-substrate complex with methyl phosphate, O-phosphoethanolamine, O-phosphopropanolamine, N-acetylphosphoserine, and phosphoglyolic acid, as well as pyrophosphatase, modified by monoesters of phosphoric acid, with pyrophosphate and tripolyphosphate, was investigated. It was shown that the enzyme containing the substrate in the active site does not react with monophosphates, but modified pyrophosphatase entirely retains the ability to bind polyanions to the regulatory site. It is concluded that the inactivation of baker's yeast inorganic pyrophosphatase by monoesters of phosphoric acid, which are affinity inhibitors of it, is the result of modification of the active site of the enzyme

  16. Aggregation and retention of human urokinase type plasminogen activator in the yeast endoplasmic reticulum

    Directory of Open Access Journals (Sweden)

    Smirnov Vladimir N

    2002-10-01

    Full Text Available Abstract Background Secretion of recombinant proteins in yeast can be affected by their improper folding in the endoplasmic reticulum and subsequent elimination of the misfolded molecules via the endoplasmic reticulum associated protein degradation pathway. Recombinant proteins can also be degraded by the vacuolar protease complex. Human urokinase type plasminogen activator (uPA is poorly secreted by yeast but the mechanisms interfering with its secretion are largely unknown. Results We show that in Hansenula polymorpha overexpression worsens uPA secretion and stimulates its intracellular aggregation. The absence of the Golgi modifications in accumulated uPA suggests that aggregation occurs within the endoplasmic reticulum. Deletion analysis has shown that the N-terminal domains were responsible for poor uPA secretion and propensity to aggregate. Mutation abolishing N-glycosylation decreased the efficiency of uPA secretion and increased its aggregation degree. Retention of uPA in the endoplasmic reticulum stimulates its aggregation. Conclusions The data obtained demonstrate that defect of uPA secretion in yeast is related to its retention in the endoplasmic reticulum. Accumulation of uPA within the endoplasmic reticulum disturbs its proper folding and leads to formation of high molecular weight aggregates.

  17. Mitogen-activated protein kinase (MAPK) dynamics determine cell fate in the yeast mating response.

    Science.gov (United States)

    Li, Yang; Roberts, Julie; AkhavanAghdam, Zohreh; Hao, Nan

    2017-12-15

    In the yeast Saccharomyces cerevisiae , the exposure to mating pheromone activates a prototypic mitogen-activated protein kinase (MAPK) cascade and triggers a dose-dependent differentiation response. Whereas a high pheromone dose induces growth arrest and formation of a shmoo-like morphology in yeast cells, lower pheromone doses elicit elongated cell growth. Previous population-level analysis has revealed that the MAPK Fus3 plays an important role in mediating this differentiation switch. To further investigate how Fus3 controls the fate decision process at the single-cell level, we developed a specific translocation-based reporter for monitoring Fus3 activity in individual live cells. Using this reporter, we observed strikingly different dynamic patterns of Fus3 activation in single cells differentiated into distinct fates. Cells committed to growth arrest and shmoo formation exhibited sustained Fus3 activation. In contrast, most cells undergoing elongated growth showed either a delayed gradual increase or pulsatile dynamics of Fus3 activity. Furthermore, we found that chemically perturbing Fus3 dynamics with a specific inhibitor could effectively redirect the mating differentiation, confirming the causative role of Fus3 dynamics in driving cell fate decisions. MAPKs mediate proliferation and differentiation signals in mammals and are therapeutic targets in many cancers. Our results highlight the importance of MAPK dynamics in regulating single-cell responses and open up the possibility that MAPK signaling dynamics could be a pharmacological target in therapeutic interventions. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

  18. Draft genome sequence of the yeast Starmerella bacillaris (syn., Candida zemplinina) FRI751 isolated from fermenting must of dried Raboso grapes

    DEFF Research Database (Denmark)

    Lemos Junior, Wilson Jose Fernandes; Treu, Laura; da Silva Duarte, Vinicius

    2017-01-01

    Starmerella bacillaris is an ascomycetous yeast commonly present in enological environments. Here, we report the first draft genome sequence of S. bacillaris FRI751, which will facilitate the study of the characteristics of this interesting enological yeast.......Starmerella bacillaris is an ascomycetous yeast commonly present in enological environments. Here, we report the first draft genome sequence of S. bacillaris FRI751, which will facilitate the study of the characteristics of this interesting enological yeast....

  19. Effect of balanced low pressure drying of curcuma longa leaf on skin immune activation activities.

    Science.gov (United States)

    Choi, Wooseok; Lim, Hye Won; Lee, Hyeon Yong

    2014-01-01

    The effect of balanced low pressure drying pretreatment associated with ultrasonication extraction (BU) on the enhancement of skin immune modulatory activities of Curcuma longa leaf was studied by comparing with conventional hot air drying (HE), freeze drying (FE) and balanced low pressure drying (BE) pretreatment processes. In considering skin immune activation activities such as the inhibition of hyaluronidase activity, the BU extract showed ca. 10% higher than those of HE, and even higher than that of the FE extract. Nitric oxide production from macrophage of the BU extract in adding 1.0 mg/mL was increased up to 16.5 μM. When measuring inhibition of IL-6 and TNF-a production from the human T lymphocytes (T cell), the BU extract also showed 53% and 78% of inhibition effect, respectively. It is found that the BU extract could effectively suppress the expression levels of skin inflammation related genes such as Cox-2 and iNOS, down to 80% and 85% compared to the control, respectively. Balanced low pressure drying process was especially active on dehydration of the leaves with minimizing the destruction and making easier elution of the bioactive substances, which resulted in higher extraction yield and better biological activities.

  20. State-of-the-art dry active waste processing facility

    International Nuclear Information System (INIS)

    Hillmer, T.; Ingalsbe, H.; Alcorn, G.; Anderson, K.; Dahlen, D.

    1989-01-01

    Palo Verde Nuclear Generating Station (PVNGS) is operated by Arizona Public Service for a consortium of seven owners. The site consists of three identical single unit power plants. Each unit is a Combustion Engineering Series 80 pressurized water reactor (PWR) rated at 1270 Megawatts electric. The site is located 100 kilometers west of Phoenix, Arizona in the arid southwest desert region of the United States of America. Since the start up of Unit One in 1985, Palo Verde has aggressively pursued waste volume reduction. This includes a dry active waste (DAW) segregation program that locates and separates nonradioactive and reusable materials that have been mixed with the radioactive DAW. The DAW program is described in further detail in the paper

  1. Segregation of low-level dry active waste

    International Nuclear Information System (INIS)

    Kornblith, L. Jr.; Naughton, M.D.; Welsh, L.

    1984-01-01

    A program has been carried out to characterize the Dry Active Waste (DAW) stream from a typical PWR power plant in order to determine the usefulness of large-volume DAW monitors for segregating such waste in order to dispose of it in appropriate facilities. A waste monitor using plastic scintillation counters was used for measuring the waste. The monitor had a volume of about 300 liters and an overall efficiency of about 12% for a typical fission product mixture. It provides automatic compensation for background radioactivity and can measure a bag of waste in less than a minute, including background measurements. Six hundred consecutively generated bags of DAW were measured. These had a total activity of about one millicurie and an average specific activity of about 540 nanocuries per kilogram. About half of the bags contained less than 1000 nanocuries and had specific activities of less than 100 nanocuries per kilogram. Based on simplified preliminary calculations, it appears that an evaluation of the risks of disposal of bags such as these in a landfill other than a low-level waste disposal facility could be carried out that would demonstrate that such disposal of half or more of these bags would not result in any substantial hazard, either short or long term

  2. Mechanical pressure and momentum conservation in dry active matter

    Science.gov (United States)

    Fily, Y.; Kafri, Y.; Solon, A. P.; Tailleur, J.; Turner, A.

    2018-01-01

    We relate the breakdown of equations of states (EOS) for the mechanical pressure of generic dry active systems to the lack of momentum conservation in such systems. We show how net sources and sinks of momentum arise generically close to confining walls. These typically depend on the interactions of the container with the particles, which makes the mechanical pressure a container-dependent quantity. We show that an EOS is recovered if the dynamics of the propulsive forces of the particles are decoupled from other degrees of freedom and lead to an apolar bulk steady-state. This recovery of an EOS stems from the mean steady-state active force density being the divergence of the flux of ‘active impulse’, an observable which measures the mean momentum particles will receive from the substrate in the future. ), which features invited work from the best early-career researchers working within the scope of J. Phys. A. This project is part of the Journal of Physics series’ 50th anniversary celebrations in 2017. Julien Tailleur was selected by the Editorial Board of J. Phys. A as an Emerging Talent.

  3. Plasmid construction using recombination activity in the fission yeast Schizosaccharomyces pombe.

    Directory of Open Access Journals (Sweden)

    Ayako Chino

    Full Text Available BACKGROUND: Construction of plasmids is crucial in modern genetic manipulation. As of now, the common method for constructing plasmids is to digest specific DNA sequences with restriction enzymes and to ligate the resulting DNA fragments with DNA ligase. Another potent method to construct plasmids, known as gap-repair cloning (GRC, is commonly used in the budding yeast Saccharomyces cerevisiae. GRC makes use of the homologous recombination activity that occurs within the yeast cells. Due to its flexible design and efficiency, GRC has been frequently used for constructing plasmids with complex structures as well as genome-wide plasmid collections. Although there have been reports indicating GRC feasibility in the fission yeast Schizosaccharomyces pombe, this species is not commonly used for GRC as systematic studies of reporting GRC efficiency in S. pombe have not been performed till date. METHODOLOGY/PRINCIPAL FINDINGS: We investigated GRC efficiency in S. pombe in this study. We first showed that GRC was feasible in S. pombe by constructing a plasmid that contained the LEU2 auxotrophic marker gene in vivo and showed sufficient efficiency with short homology sequences (>25 bp. No preference was shown for the sequence length from the cut site in the vector plasmid. We next showed that plasmids could be constructed in a proper way using 3 DNA fragments with 70% efficiency without any specific selections being made. The GRC efficiency with 3 DNA fragments was dramatically increased >95% in lig4Delta mutant cell, where non-homologous end joining is deficient. Following this approach, we successfully constructed plasmid vectors with leu1+, ade6+, his5+, and lys1+ markers with the low-copy stable plasmid pDblet as a backbone by applying GRC in S. pombe. CONCLUSIONS/SIGNIFICANCE: We concluded that GRC was sufficiently feasible in S. pombe for genome-wide gene functional analysis as well as for regular plasmid construction. Plasmids with different

  4. Inaccurate DNA synthesis in cell extracts of yeast producing active human DNA polymerase iota.

    Science.gov (United States)

    Makarova, Alena V; Grabow, Corinn; Gening, Leonid V; Tarantul, Vyacheslav Z; Tahirov, Tahir H; Bessho, Tadayoshi; Pavlov, Youri I

    2011-01-31

    Mammalian Pol ι has an unusual combination of properties: it is stimulated by Mn(2+) ions, can bypass some DNA lesions and misincorporates "G" opposite template "T" more frequently than incorporates the correct "A." We recently proposed a method of detection of Pol ι activity in animal cell extracts, based on primer extension opposite the template T with a high concentration of only two nucleotides, dGTP and dATP (incorporation of "G" versus "A" method of Gening, abbreviated as "misGvA"). We provide unambiguous proof of the "misGvA" approach concept and extend the applicability of the method for the studies of variants of Pol ι in the yeast model system with different cation cofactors. We produced human Pol ι in baker's yeast, which do not have a POLI ortholog. The "misGvA" activity is absent in cell extracts containing an empty vector, or producing catalytically dead Pol ι, or Pol ι lacking exon 2, but is robust in the strain producing wild-type Pol ι or its catalytic core, or protein with the active center L62I mutant. The signature pattern of primer extension products resulting from inaccurate DNA synthesis by extracts of cells producing either Pol ι or human Pol η is different. The DNA sequence of the template is critical for the detection of the infidelity of DNA synthesis attributed to DNA Pol ι. The primer/template and composition of the exogenous DNA precursor pool can be adapted to monitor replication fidelity in cell extracts expressing various error-prone Pols or mutator variants of accurate Pols. Finally, we demonstrate that the mutation rates in yeast strains producing human DNA Pols ι and η are not elevated over the control strain, despite highly inaccurate DNA synthesis by their extracts.

  5. Inaccurate DNA synthesis in cell extracts of yeast producing active human DNA polymerase iota.

    Directory of Open Access Journals (Sweden)

    Alena V Makarova

    2011-01-01

    Full Text Available Mammalian Pol ι has an unusual combination of properties: it is stimulated by Mn(2+ ions, can bypass some DNA lesions and misincorporates "G" opposite template "T" more frequently than incorporates the correct "A." We recently proposed a method of detection of Pol ι activity in animal cell extracts, based on primer extension opposite the template T with a high concentration of only two nucleotides, dGTP and dATP (incorporation of "G" versus "A" method of Gening, abbreviated as "misGvA". We provide unambiguous proof of the "misGvA" approach concept and extend the applicability of the method for the studies of variants of Pol ι in the yeast model system with different cation cofactors. We produced human Pol ι in baker's yeast, which do not have a POLI ortholog. The "misGvA" activity is absent in cell extracts containing an empty vector, or producing catalytically dead Pol ι, or Pol ι lacking exon 2, but is robust in the strain producing wild-type Pol ι or its catalytic core, or protein with the active center L62I mutant. The signature pattern of primer extension products resulting from inaccurate DNA synthesis by extracts of cells producing either Pol ι or human Pol η is different. The DNA sequence of the template is critical for the detection of the infidelity of DNA synthesis attributed to DNA Pol ι. The primer/template and composition of the exogenous DNA precursor pool can be adapted to monitor replication fidelity in cell extracts expressing various error-prone Pols or mutator variants of accurate Pols. Finally, we demonstrate that the mutation rates in yeast strains producing human DNA Pols ι and η are not elevated over the control strain, despite highly inaccurate DNA synthesis by their extracts.

  6. The H159A mutant of yeast enolase 1 has significant activity.

    Science.gov (United States)

    Brewer, J M; Holland, M J; Lebioda, L

    2000-10-05

    The function of His159 in the enolase mechanism is disputed. Recently, Vinarov and Nowak (Biochemistry (1999) 38, 12138-12149) prepared the H159A mutant of yeast enolase 1 and expressed this in Escherichia coli. They reported minimal (ca. 0.01% of the native value) activity, though the protein appeared to be correctly folded, according to its CD spectrum, tryptophan fluorescence, and binding of metal ion and substrate. We prepared H159A enolase using a multicopy plasmid and expressed the enzyme in yeast. Our preparations of H159A enolase have 0.2-0.4% of the native activity under standard assay conditions and are further activated by Mg(2+) concentrations above 1 mM to 1-1.5% of the native activity. Native enolase 1 (and enolase 2) are inhibited by such Mg(2+) concentrations. It is possible that His159 is necessary for correct folding of the enzyme and that expression in E. coli leads to largely misfolded protein. Copyright 2000 Academic Press.

  7. Environmental assessment of different strategies for production of stabilized yeast

    OpenAIRE

    Monclus, Vincent; Pénicaud, Caroline; Perret, Bruno; Fonseca, Fernanda

    2016-01-01

    Yeast are widely used for producing fermented (bread, beer...) and health benefit (probiotics) products. The production of stable and active yeast involves fermentation, concentration, protection, drying (stabilization) and storage. During the stabilization and storage steps, the cells face numerous stress which may deteriorate functional properties and cause cell death. Different strategies can be used to preserve cell survival, such as changing growth medium for fermentation or adapting pro...

  8. Detecting estrogenic activity in water samples withestrogen-sensitive yeast cells using spectrophotometry and fluorescencemicroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Wozei, E.; Holman, H-Y.N.; Hermanowicz, S.W.; Borglin S.

    2006-03-15

    Environmental estrogens are environmental contaminants that can mimic the biological activities of the female hormone estrogen in the endocrine system, i.e. they act as endocrine disrupters. Several substances are reported to have estrogen-like activity or estrogenic activity. These include steroid hormones, synthetic estrogens (xenoestrogens), environmental pollutants and phytoestrogens (plant estrogens). Using the chromogenic substrate ortho-nitrophenyl-{beta}-D-galactopyranoside (ONPG) we show that an estrogen-sensitive yeast strain RMY/ER-ERE, with human estrogen receptor (hER{alpha}) gene and the lacZ gene which encodes the enzyme {beta}-galactosidase, is able to detect estrogenic activity in water samples over a wide range of spiked concentrations of the hormonal estrogen 17{beta}-estradiol (E2). Ortho-nitrophenol (ONP), the yellow product of this assay can be detected using spectrophotometry but requires cell lysis to release the enzyme and allow product formation. We improved this aspect in a fluorogenic assay by using fluorescein di-{beta}-D-galactopyranoside (FDG) as a substrate. The product was visualized using fluorescence microscopy without the need to kill, fix or lyse the cells. We show that in live yeast cells, the uptake of E2 and the subsequent production of {beta}-galactosidase enzyme occur quite rapidly, with maximum enzyme-catalyzed fluorescent product formation evident after about 30 minutes of exposure to E2. The fluorogenic assay was applied to a selection of estrogenic compounds and the Synchrotron-based Fourier transform infrared (SR-FTIR) spectra of the cells obtained to better understand the yeast whole cell response to the compounds. The fluorogenic assay is most sensitive to E2, but the SR-FTIR spectra suggest that the cells respond to all the estrogenic compounds tested even when no fluorescent response was detected. These findings are promising and may shorten the duration of environmental water screening and monitoring regimes using

  9. Yeasts preservation: alternatives for lyophilisation

    OpenAIRE

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

    2012-01-01

    The aim of the study was to compare the effect of two low-cost, low technology traditional methods for drying starter cultures with standard lyophilisation. Lyophilised yeast cultures and yeast cultures preserved in dry rice cakes and dry plant fibre strands were examined for viable cell counts during 6 months storage at 4 and 25 °C. None of the yeast cultures showed a significant loss in viable cell count during 6 months of storage at 4 °C upon lyophilisation and preservation in dry rice cak...

  10. A Comparative Evaluation of Dried Activated Sludge and Mixed Dried Activated Sudge with Rice Husk silica to Remove Hydrogen Sulfide

    Directory of Open Access Journals (Sweden)

    Seyed Mahmoud Mehdinia

    2013-03-01

    Full Text Available The aim of this study was to investigate the effectiveness of dried activated sludge (DAS and mixed dried activated sludge with rice husk silica (DAS & RHS for removal of hydrogen sulfide (H2S. Two laboratory-scale filter columns (packed one litter were operated. Both systems were operated under different conditions of two parameters, namely different inlet gas concentrations and different inlet flow rates. The DAS & RHS packed filter showed more than 99.96% removal efficiency (RE with empty bed residence time (EBRT of 45 to 90 s and 300 mg/L inlet concentration of H2S. However, the RE decreased to 96.87% with the EBRT of 30 s. In the same condition, the DAS packed filter showed 99.37% RE. Nonetheless, the RE was shown to have dropped to 82.09% with the EBRT of 30 s. The maximum elimination capacity (EC was obtained in the DAS & RHS packed filter up to 52.32 g/m3h, with the RE of 96.87% and H2S mass loading rate of 54 g/m3h. The maximum EC in the DAS packed filter was obtained up to 44.33 g/m3h with the RE of 82.09% and the H2S mass loading rate of 54 g/m3h. After 53 days of operating time and 54 g/m3h of loading rates, the maximum pressure drop reached to 3.0 and 8.0 (mm H2O for the DAS & RHS packed and DAS packed filters, respectively. Based on the findings of this study, the DAS & RHS could be considered as a more suitable packing material to remove H2S.

  11. MET18 Deficiency Increases the Sensitivity of Yeast to Oxidative Stress and Shortens Replicative Lifespan by Inhibiting Catalase Activity.

    Science.gov (United States)

    Chen, Ya-Qin; Liu, Xin-Guang; Zhao, Wei; Cui, Hongjing; Ruan, Jie; Yuan, Yuan; Tu, Zhiguang

    2017-01-01

    Yeast MET18 , a subunit of the cytosolic iron-sulfur (Fe/S) protein assembly (CIA) machinery which is responsible for the maturation of Fe/S proteins, has been reported to participate in the oxidative stress response. However, the underlying molecular mechanisms remain unclear. In this study, we constructed a MET18/met18Δ heterozygous mutant yeast strain and found that MET18 deficiency in yeast cells impaired oxidative stress resistance as evidenced by increased sensitivity to hydrogen peroxide (H 2 O 2 ) and cumene hydroperoxide (CHP). Mechanistically, the mRNA levels of catalase A (CTA1) and catalase T (CTT1) as well as the total catalase activity were significantly reduced in MET18 -deficient cells. In contrast, overexpression of CTT1 or CTA1 in MET18 -deficient cells significantly increased the intracellular catalase activity and enhanced the resistance ability against H 2 O 2 and CHP. In addition, MET18 deficiency diminished the replicative capacity of yeast cells as evidenced by the shortened replicative lifespan, which can be restored by CTT1 overexpression, but not by CTA1 , in the MET18 -deficient cells. These results suggest that MET18 , in a catalase-dependent manner, plays an essential role in enhancing the resistance of yeast cells to oxidative stress and increasing the replicative capacity of yeast cells.

  12. Spermine modulates fungal morphogenesis and activates plasma membrane H+-ATPase during yeast to hyphae transition

    Directory of Open Access Journals (Sweden)

    Antônio Jesus Dorighetto Cogo

    2018-02-01

    Full Text Available Polyamines play a regulatory role in eukaryotic cell growth and morphogenesis. Despite many molecular advances, the underlying mechanism of action remains unclear. Here, we investigate a mechanism by which spermine affects the morphogenesis of a dimorphic fungal model of emerging relevance in plant interactions, Yarrowia lipolytica, through the recruitment of a phytohormone-like pathway involving activation of the plasma membrane P-type H+-ATPase. Morphological transition was followed microscopically, and the H+-ATPase activity was analyzed in isolated membrane vesicles. Proton flux and acidification were directly probed at living cell surfaces by a non-invasive selective ion electrode technique. Spermine and indol-3-acetic acid (IAA induced the yeast-hypha transition, influencing the colony architecture. Spermine induced H+-ATPase activity and H+ efflux in living cells correlating with yeast-hypha dynamics. Pharmacological inhibition of spermine and IAA pathways prevented the physio-morphological responses, and indicated that spermine could act upstream of the IAA pathway. This study provides the first compelling evidence on the fungal morphogenesis and colony development as modulated by a spermine-induced acid growth mechanism analogous to that previously postulated for the multicellular growth regulation of plants.

  13. Antifungal activity and mechanism of action of monoterpenes against dermatophytes and yeasts

    Directory of Open Access Journals (Sweden)

    Diogo Miron

    Full Text Available Dermatomycosis causes highly frequent dermal lesions, and volatile oils have been proven to be promising as antifungal agents. The antifungal activity of geraniol, nerol, citral, neral and geranial (monoterpenes, and terbinafine and anidulafungin (control drugs against seven opportunistic pathogenic yeasts and four dermatophyte species was evaluated by the Clinical and Laboratory Standards Institute microdilution tests. Monoterpenes were more active against dermatophytes than yeasts (geometric mean of minimal inhibitory concentration (GMIC of 34.5 and 100.4 µg.ml-1, respectively. Trichophyton rubrum was the fungal species most sensitive to monoterpenes (GMIC of 22.9 µg.ml-1. The trans isomers showed higher antifungal activity than the cis. The mechanism of action was investigated evaluating damage in the fungal cell wall (Sorbitol Protection Assay and in the cell membrane (Ergosterol Affinity Assay. No changes were observed in the MIC of monoterpenes in the sorbitol protection assay.The MIC of citral and geraniol was increased from 32 to 160 µg.ml-1 when the exogenous ergosterol concentrations was zero and 250 µg.ml-1, respectively. The monoterpenes showed an affinity for ergosterol relating their mechanism of action to cell membrane destabilization.

  14. Neutron activation analysis of cadmium bioremediation by yeast isolated from the fermentation of cachaca

    International Nuclear Information System (INIS)

    Ribeiro, Frederico H.; Moreira, Luciana M.C.; Porto, Barbara A.A.; Menezes, Maria Angela B.C.; Amaral, Angela M.; Neves, Maria J.; Rosa, Carlos A.

    2009-01-01

    The accumulation of heavy metal in urban environment is a final result of industrial waste discharges. The removal and recovery of heavy metals from contaminated water and wastewater is important in the protection of the environment and human health. There are several chemical technologies used to remove heavy metals. Most of these are ineffective or excessively expensive when the metal concentrations are less than 100 mgL -1 . Biological treatment with bioremediation, is an innovative technology available for heavy metal polluted wastewaters. Brazil has a big production of yeast as a by-product of the fermentation of sugar cane for the production of ethanol or, for the production of artisanal cachaca, notedly in the state of Minas Gerais. Biological organisms remove metals through of two processes: bioaccumulation and biosorption. This research used neutron activation technique to determine the capacity of 10 isolated yeast of the fermentation for the withdrawal of cadmium. The efflux of ions K + , was also analyzed by the same technique after the incorporation of cadmium by cells. This work showed that the neutron activation analysis is a suitable technique to quantification the metal absorbed from liquid solution and that isolated strains of the fermentation of cachaca are more efficient in removing cadmium of the liquid solution that the laboratorial strain. The influences of the metals on the growth of the cells are also observed. The results obtained were compared with the yeast strain of laboratory, Saccharomyces cerevisiae W303-WT. The tolerance of cadmium to concentration of 100 mgL -1 was evaluated. (author)

  15. Neutron activation analysis of cadmium bioremediation by yeast isolated from the fermentation of cachaca

    Energy Technology Data Exchange (ETDEWEB)

    Ribeiro, Frederico H.; Moreira, Luciana M.C.; Porto, Barbara A.A.; Menezes, Maria Angela B.C.; Amaral, Angela M.; Neves, Maria J. [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)], e-mail: fhr@cdtn.br; Rosa, Carlos A. [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil)], e-mail: carlrosa@icb.ufmg.br

    2009-07-01

    The accumulation of heavy metal in urban environment is a final result of industrial waste discharges. The removal and recovery of heavy metals from contaminated water and wastewater is important in the protection of the environment and human health. There are several chemical technologies used to remove heavy metals. Most of these are ineffective or excessively expensive when the metal concentrations are less than 100 mgL{sup -1}. Biological treatment with bioremediation, is an innovative technology available for heavy metal polluted wastewaters. Brazil has a big production of yeast as a by-product of the fermentation of sugar cane for the production of ethanol or, for the production of artisanal cachaca, notedly in the state of Minas Gerais. Biological organisms remove metals through of two processes: bioaccumulation and biosorption. This research used neutron activation technique to determine the capacity of 10 isolated yeast of the fermentation for the withdrawal of cadmium. The efflux of ions K{sup +}, was also analyzed by the same technique after the incorporation of cadmium by cells. This work showed that the neutron activation analysis is a suitable technique to quantification the metal absorbed from liquid solution and that isolated strains of the fermentation of cachaca are more efficient in removing cadmium of the liquid solution that the laboratorial strain. The influences of the metals on the growth of the cells are also observed. The results obtained were compared with the yeast strain of laboratory, Saccharomyces cerevisiae W303-WT. The tolerance of cadmium to concentration of 100 mgL{sup -1} was evaluated. (author)

  16. Management of the endoplasmic reticulum stress by activation of the heat shock response in yeast

    DEFF Research Database (Denmark)

    Hou, Jin; Tang, Hongting; Liu, Zihe

    2014-01-01

    In yeast Saccharomyces cerevisiae, accumulation of misfolded proteins in the endoplasmic reticulum (ER) causes ER stress and activates the unfolded protein response (UPR), which is mediated by Hac1p. The heat shock response (HSR) mediated by Hsf1p, mainly regulates cytosolic processes and protects...... the cell from stresses. Here, we find that a constitutive activation of the HSR could increase ER stress resistance in both wild-type and UPR-deficient cells. Activation of HSR decreased UPR activation in the WT (as shown by the decreased HAC1 mRNA splicing). We analyzed the genome-wide transcriptional...... response in order to propose regulatory mechanisms that govern the interplay between UPR and HSR and followed up for the hypotheses by experiments in vivo and in vitro. Interestingly, we found that the regulation of ER stress response via HSR is (1) only partially dependent on over-expression of Kar2p (ER...

  17. In Vitro Activities of Terbinafine against Cutaneous Isolates of Candida albicans and Other Pathogenic Yeasts

    Science.gov (United States)

    Ryder, Neil S.; Wagner, Sonja; Leitner, Ingrid

    1998-01-01

    Terbinafine is active in vitro against a wide range of pathogenic fungi, including dermatophytes, molds, dimorphic fungi, and some yeasts, but earlier studies indicated that the drug had little activity against Candida albicans. In contrast, clinical studies have shown topical and oral terbinafine to be active in cutaneous candidiasis and Candida nail infections. In order to define the anti-Candida activity of terbinafine, we tested the drug against 350 fresh clinical isolates and additional strains by using a broth dilution assay standardized according to the guidelines of the National Committee for Clinical Laboratory Standards (NCCLS) M27-A assay. Terbinafine was found to have an MIC of 1 μg/ml for reference C. albicans strains. For 259 clinical isolates, the MIC at which 50% of the isolates are inhibited (MIC50) of terbinafine was 1 μg/ml (fluconazole, 0.5 μg/ml), and the MIC90 was 4 μg/ml (fluconazole, 1 μg/ml). Terbinafine was highly active against Candida parapsilosis (MIC90, 0.125 μg/ml) and showed potentially interesting activity against isolates of Candida dubliniensis, Candida guilliermondii, Candida humicola, and Candida lusitaniae. It was not active against the Candida glabrata, Candida krusei, and Candida tropicalis isolates in this assay. Cryptococcus laurentii and Cryptococcus neoformans were highly susceptible to terbinafine, with MICs of 0.06 to 0.25 μg/ml. The NCCLS macrodilution assay provides reproducible in vitro data for terbinafine against Candida and other yeasts. The MICs for C. albicans and C. parapsilosis are compatible with the known clinical efficacy of terbinafine in cutaneous infections, while the clinical relevance of its activities against the other species has yet to be determined. PMID:9593126

  18. Quality factors, antioxidant activity, and sensory properties of jet-tube dried rabbiteye blueberries.

    Science.gov (United States)

    Pallas, Laura A; Pegg, Ronald B; Kerr, William L

    2013-06-01

    Rabbiteye blueberries are an excellent source of nutrients and phytochemicals. They are often dried, which can degrade health-promoting compounds. Means of shortening exposure to high-temperature drying air are desirable. Five cultivars of rabbiteye blueberries ('Premier', 'Tifblue', 'Brightwell', 'Alapaha', and 'Powderblue') were dried in a jet-tube fluidized bed air dryer with varying pretreatments including mechanical abrasion and osmotic dehydration. Drying time ranged from 66 to 95 min at 107 °C, achieving a final water activity of 0.347-0.605. Prior osmotic dehydration significantly reduced the drying time. Vacuum osmotic dehydration for 70 min achieved similar moisture contents to soaking blueberries for 24 h. Jet-tube dried blueberries exhibited greater color saturation than commercially available blueberries. While drying reduced the total monomeric anthocyanin (TMA) content, this occurred to a lesser extent than by other processing methods. The total phenolics content (TPC) and antioxidant capacity (H-ORACFL values) increased after drying. 'Premier' was the most preferred vacuum-infused dried blueberry, with a water activity (aw) of 0.53 and 157 g H2O kg(-1). 'Tifblue' was most preferred amongst the overnight-infused and also unsweetened dried blueberries. Jet-tube drying can substantially reduce drying times while yielding blueberries with good color, sensory properties, TMA, TPC, and H-ORACFL values. Furthermore, some cultivars produce better-quality dried blueberries than others. © 2012 Society of Chemical Industry.

  19. Whole-genome sequence of Starmerella bacillaris PAS13, a nonconventional enological yeast with antifungal activity

    DEFF Research Database (Denmark)

    Lemos Junior, Wilson Jose Fernandes; Treu, Laura; Duarte, Vinicius da Silva

    2017-01-01

    Starmerella bacillaris is a fermentative yeast commonly found in vineyards. Here, we present the draft genome sequence of S. bacillaris PAS13, a nonconventional enological yeast with a potential role as a biocontrol agent. This gene sequence will provide insights into the genetic basis of yeast...

  20. Yeast for virus research

    Science.gov (United States)

    Zhao, Richard Yuqi

    2017-01-01

    Budding yeast (Saccharomyces cerevisiae) and fission yeast (Schizosaccharomyces pombe) are two popular model organisms for virus research. They are natural hosts for viruses as they carry their own indigenous viruses. Both yeasts have been used for studies of plant, animal and human viruses. Many positive sense (+) RNA viruses and some DNA viruses replicate with various levels in yeasts, thus allowing study of those viral activities during viral life cycle. Yeasts are single cell eukaryotic organisms. Hence, many of the fundamental cellular functions such as cell cycle regulation or programed cell death are highly conserved from yeasts to higher eukaryotes. Therefore, they are particularly suited to study the impact of those viral activities on related cellular activities during virus-host interactions. Yeasts present many unique advantages in virus research over high eukaryotes. Yeast cells are easy to maintain in the laboratory with relative short doubling time. They are non-biohazardous, genetically amendable with small genomes that permit genome-wide analysis of virologic and cellular functions. In this review, similarities and differences of these two yeasts are described. Studies of virologic activities such as viral translation, viral replication and genome-wide study of virus-cell interactions in yeasts are highlighted. Impacts of viral proteins on basic cellular functions such as cell cycle regulation and programed cell death are discussed. Potential applications of using yeasts as hosts to carry out functional analysis of small viral genome and to develop high throughput drug screening platform for the discovery of antiviral drugs are presented. PMID:29082230

  1. [The in vitro antifungal activities of fluconazole against pathogenic yeasts recently isolated from clinical specimens].

    Science.gov (United States)

    Yamaguchi, H; Igari, J; Kume, H; Abe, M; Oguri, T; Kanno, H; Kawakami, S; Okuzumi, K; Fukayama, M; Ito, A; Kawata, K; Uchida, K

    1997-09-01

    The emergence of Candida albicans resistance to azole antifungal agents have been reported in the U. S. and Europe. We examined the in vitro antifungal activities of fluconazole against clinical isolates collected by seven investigators in three years to examine if a tendency existed toward the development of azole-resistance among fungal isolates in Japan. The following results were obtained: 1. Sensitivities to fluconazole (FLCZ) were determined for yeast-like fungi, including 113 strains isolated in 1993, 149 strains isolated in 1994 and 205 strains isolated in 1995. No significant differences in sensitivities in the three years were detected. 2. Minimum inhibitory concentrations of FLCZ were 0.1-0.78 microgram/ml for C. albicans and 3.13-25 micrograms/ml for C. glabrata. Strains with 25 micrograms/ml of FLCZ's MIC were detected; two strains of C. krusei and one strain each of C. krusei, Trichospron beigelii and Hansenula anomala. No strains with higher than 50 micrograms/ml MIC of FLCZ were detected. 3. In vitro activities of FLCZ were compared between clinical strains isolated between 1993 and 1995 and clinical strains isolated before the marketing of FLCZ (up to December 1987) or clinical yeasts isolated between 1991 and 1992. No significant differences were observed, suggesting that no tendency existed toward azole resistance among fungal strains examined.

  2. Estrogenic Activities of Food Supplements and Beers as Assessed by a Yeast Bioreporter Assay.

    Science.gov (United States)

    Omoruyi, Iyekhoetin Matthew; Pohjanvirta, Raimo

    2017-10-31

    Mounting evidence of the effects of endocrine-disrupting chemicals (EDCs) in humans has led to assaying a vast array of food items (processed or packaged) as possible sources of human exposure to estrogens. In this study, we investigated the current situation in this respect of different food supplements and beer brands. Eleven food supplements and 24 beer brands were obtained from Helsinki, Finland. Sample preparation was carried out by established methods while estrogenic activities were assessed by a yeast bioluminescent assay, using two recombinant yeast strains (Saccharomyces cerevisiae BMAEREluc/ERα and S. cerevisiae BMA64/luc). All the food supplements as well as 81% of the beer samples tested were found to be estrogenic, with estradiol equivalent concentrations of food supplements and beer brands ranging from 7.5 to 11.5 µg/ml and from below detection limits to 43.6 ng/ml, respectively. The estrogenic activities detected in beer samples were not dependent on the beer's alcoholic content, the country of production, or the size of the production brewery. The results of our study imply that both food supplements and beers can be a significant source of human exposure to estrogens. Therefore, further studies and regular surveillance are warranted.

  3. Functional properties of the two redox-active sites in yeast protein disulphide isomerase in vitro and in vivo

    DEFF Research Database (Denmark)

    Westphal, V; Darby, N J; Winther, Jakob R.

    1999-01-01

    to that of human PDI, both in rearrangement and oxidation reactions. However, while the a domain active site of the human enzyme is more active than the a'-site, the reverse is the case for yPDI. This prompted us to set up an assay to investigate whether the situation would be different with a native yeast......-site to be most important. We furthermore show that the apparent difference between in vivo and in vitro activities is not due to catalytic contributions from the other PDI homologues found in yeast....

  4. The Influence of Different Air-Drying Conditions on Bioactive Compounds and Antioxidant Activity of Berries.

    Science.gov (United States)

    Bustos, Mariela C; Rocha-Parra, Diego; Sampedro, Ines; de Pascual-Teresa, Sonia; León, Alberto E

    2018-03-21

    The aim of the present research was to study the effect of convective drying on color, bioactive compounds, and antioxidant activity of berry fruits and to chemically characterize the polyphenolic composition of raspberry, boysenberry, redcurrants, and blackcurrants fruit. Drying berries at 65 °C provoked the best conservations of color, particularly for boysenberry and blackcurrant. Drying at 65 °C was also the condition that showed higher level of polyphenols, while drying at 50 or 130 °C showed above % degradation of them due to the long time or high temperature drying. Radical scavenging activity was the predominant antioxidant mechanism in all samples, with 65 °C dried berries being the most active ones possibly because of polyphenol depolymerization. The anthocyanin profile showed that delphinidin and cyanidin derivatives were the most abundant anthocyanidins with different predominance between berry genera. Degradation of anthocyanins was increased with drying temperature been Cy 3-glucoside and Cy 3-rutinoside the most abundant.

  5. Aroma-active components of nonfat dry milk.

    Science.gov (United States)

    Karagül-Yüceer, Y; Drake, M A; Cadwallader, K R

    2001-06-01

    Application of aroma extract dilution analysis (AEDA) on the volatile components of low-, medium-, and high-heat-treated nonfat dry milks (NDM) revealed aroma-active compounds in the log(3) flavor dilution (log(3) FD) factor range of 1 to 6. The following compounds contributed the highest log(3) FD factors to overall NDM flavor: 2,5-dimethyl-4-hydroxy-3(2H)-furanone [(Furaneol), burnt sugar-like]; butanoic acid (rancid); 3-(methylthio)propanal [(methional), boiled potato-like]; o-aminoacetophenone (grape-like); delta-decalactone (sweet); (E)-4,5-epoxy-(E)-2-decenal (metallic); pentanoic acid (sweaty); 4,5-dimethyl-3-hydroxy-2(5H)-furanone [(sotolon), curry]; 3-methoxy-4-hydroxybenzaldehyde [(vanillin), vanilla]; 2-acetyl-1-pyrroline and 2-acetyl-2-thiazoline (popcorn-like); hexanoic acid (vinegar-like); phenylacetic acid (rose-like); octanoic acid (waxy); nonanal (fatty); and 1-octen-3-one (mushroom-like). The odor intensities of Furaneol, butanoic acid, methional, o-aminoacetophenone, sotolon, vanillin, (E)-4,5-epoxy-(E)-2-decenal, and phenylacetic acid were higher in high-heat-treated samples than others. However, the odor intensities of lactones, 2-acetyl-1-pyrroline, and 2-acetyl-2-thiazoline were not affected by heat treatment. Sensory evaluation results also revealed that heat-generated flavors have a major impact on the flavor profile of NDM.

  6. Antimicrobial activity of some Pacific Northwest woods against anaerobic bacteria and yeast.

    Science.gov (United States)

    Johnston, W H; Karchesy, J J; Constantine, G H; Craig, A M

    2001-11-01

    Extracts of woods commonly used for animal bedding were tested for antimicrobial activity. Essential oils from Alaska cedar (Chamaecyparis nootkatensis), western juniper (Juniperus occidentalis) and old growth Douglas fir (Pseudotsuga menziesii) as well as methanol extracts of wood from these trees plus western red cedar (Thuja plicata) and ponderosa pine (Pinus ponderosa) were tested for antimicrobial activity against anaerobic bacteria and yeast. The test microbes included Fusobacterium necrophorum, Clostridium perfringens, Actinomyces bovis and Candida albicans which are common to foot diseases and other infections in animals. The essential oils and methanol extracts were tested using a standardized broth assay. Only extracts of Alaska cedar and western juniper showed significant antimicrobial activity against each of the microbes tested. The essential oil of Douglas fir did show antimicrobial activity against A. bovis at the concentrations tested. The methanol extracts of the heartwood of Douglas fir and the sapwood of ponderosa pine showed no antimicrobial activity. The major chemical components of western juniper (cedrol and alpha- and beta-cedrene) and Alaska cedar (nootkatin) were also tested. In western juniper, alpha- and beta-cedrene were found to be active components. Nootkatin showed activity only against C. albicans. The inhibitory activity in Alaska cedar oil was high enough to justify further efforts to define the other chemical components responsible for the antimicrobial activity. Copyright 2001 John Wiley & Sons, Ltd.

  7. Activation of a yeast replication origin near a double-stranded DNA break.

    Science.gov (United States)

    Raghuraman, M K; Brewer, B J; Fangman, W L

    1994-03-01

    Irradiation in the G1 phase of the cell cycle delays the onset of DNA synthesis and transiently inhibits the activation of replication origins in mammalian cells. It has been suggested that this inhibition is the result of the loss of torsional tension in the DNA after it has been damaged. Because irradiation causes DNA damage at an undefined number of nonspecific sites in the genome, it is not known how cells respond to limited DNA damage, and how replication origins in the immediate vicinity of a damage site would behave. Using the sequence-specific HO endonuclease, we have created a defined double-stranded DNA break in a centromeric plasmid in G1-arrested cells of the yeast Saccharomyces cerevisiae. We show that replication does initiate at the origin on the cut plasmid, and that the plasmid replicates early in the S phase after linearization in vivo. These observations suggest that relaxation of a supercoiled DNA domain in yeast need not inactivate replication origins within that domain. Furthermore, these observations rule out the possibility that the late replication context associated with chromosomal termini is a consequence of DNA ends.

  8. Change in activity of serine palmitoyltransferase affects sensitivity to syringomycin E in yeast Saccharomyces cerevisiae.

    Science.gov (United States)

    Toume, Moeko; Tani, Motohiro

    2014-09-01

    Syringomycin E is a cyclic lipodepsipeptide produced by strains of the plant bacterium Pseudomonas syringae pv. syringae. Genetic studies involving the yeast Saccharomyces cerevisiae have revealed that complex sphingolipids play important roles in the action of syringomycin E. Here, we found a novel mutation that confers resistance to syringomycin E on yeast; that is, a deletion mutant of ORM1 and ORM2, which encode negative regulators of serine palmitoyltransferase catalyzing the initial step of sphingolipid biosynthesis, exhibited resistance to syringomycin E. On the contrary, overexpression of Orm2 resulted in high sensitivity to the toxin. Moreover, overexpression of Lcb1 and Lcb2, catalytic subunits of serine palmitoyltransferase, causes resistance to the toxin, whereas partial repression of expression of Lcb1 had the opposite effect. Partial reduction of complex sphingolipids by repression of expression of Aur1, an inositol phosphorylceramide synthase, also resulted in high sensitivity to the toxin. These results suggested that an increase in sphingolipid biosynthesis caused by a change in the activity of serine palmitoyltransferase causes resistance to syringomycin E. © 2014 Federation of European Microbiological Societies. Published by John Wiley & Sons Ltd. All rights reserved.

  9. Regulation of the Stress-Activated Degradation of Mitochondrial Respiratory Complexes in Yeast

    Directory of Open Access Journals (Sweden)

    Alba Timón-Gómez

    2018-01-01

    Full Text Available Repair and removal of damaged mitochondria is a key process for eukaryotic cell homeostasis. Here we investigate in the yeast model how different protein complexes of the mitochondrial electron transport chain are subject to specific degradation upon high respiration load and organelle damage. We find that the turnover of subunits of the electron transport complex I equivalent and complex III is preferentially stimulated upon high respiration rates. Particular mitochondrial proteases, but not mitophagy, are involved in this activated degradation. Further mitochondrial damage by valinomycin treatment of yeast cells triggers the mitophagic removal of the same respiratory complexes. This selective protein degradation depends on the mitochondrial fusion and fission apparatus and the autophagy adaptor protein Atg11, but not on the mitochondrial mitophagy receptor Atg32. Loss of autophagosomal protein function leads to valinomycin sensitivity and an overproduction of reactive oxygen species upon mitochondrial damage. A specific event in this selective turnover of electron transport chain complexes seems to be the association of Atg11 with the mitochondrial network, which can be achieved by overexpression of the Atg11 protein even in the absence of Atg32. Furthermore, the interaction of various Atg11 molecules via the C-terminal coil domain is specifically and rapidly stimulated upon mitochondrial damage and could therefore be an early trigger of selective mitophagy in response to the organelles dysfunction. Our work indicates that autophagic quality control upon mitochondrial damage operates in a selective manner.

  10. The fermentative activity and morphological specialitys of yeast Saccharomyces cerevisiae Y-503 at cultivation in aerobic and anaerobic conditions

    Directory of Open Access Journals (Sweden)

    S. Ts. Kotenko

    2010-01-01

    Full Text Available The influence of aerobic and anaerobic conditions of cultivation on structure of cells and enzymes` activity of yeast S. cerevisiae Y-503 is researched. The results of experiment have shown that nutrient medium containing geothermal water in aerobic conditions of cultivation improves biotechnological properties of yeast important for manufacturing bread, and anaerobic activates the enzymes participating in synthesis of ethanol. Strain S. cerevisiae Y-503 can successfully be used both in baking, and in the spirit industries

  11. Oral application of freeze-dried yeast particles expressing the PCV2b Cap protein on their surface induce protection to subsequent PCV2b challenge in vivo.

    Science.gov (United States)

    Patterson, Robert; Eley, Thomas; Browne, Christopher; Martineau, Henny M; Werling, Dirk

    2015-11-17

    Porcine circovirus type 2 (PCV2) is now endemic in every major pig producing country, causing PCV-associated disease (PCVAD), linked with large scale economic losses. Current vaccination strategies are based on the capsid protein of the virus and are reasonably successful in preventing PCVAD but fail to induce sterile immunity. Additionally, vaccinating whole herds is expensive and time consuming. In the present study a "proof of concept" vaccine trial was employed to test the effectiveness of powdered freeze-dried recombinant Saccharomyces cerevisiae yeast stably expressing the capsid protein of PCV2b on its surface as an orally applied vaccine. PCV2-free pigs were given 3 doses of vaccine or left un-vaccinated before challenge with a defined PCV2b strain. Rectal temperatures were measured and serum and faeces samples were collected weekly. At the end of the study, pigs were euthanized, tissue samples taken and tested for PCV2b load by qPCR and immunohistochemistry. The peak of viraemia in sera and faeces of unvaccinated pigs was higher than that of vaccinated pigs. Additionally more sIgA was found in faeces of vaccinated pigs than unvaccinated. Vaccination was associated with lower serum concentrations of TNFα and IL-1β but higher concentrations of IFNα and IFNγ in comparison to the unvaccinated animals. At the end of the trial, a higher viral load was found in several lymphatic tissues and the ileum of unvaccinated pigs in comparison to vaccinated pigs. The difference between groups was especially apparent in the ileum. The results presented here demonstrate a possible use for recombinant S. cerevisiae expressing viral proteins as an oral vaccine against PCV2. A powdered freeze-dried recombinant S. cerevisiae used as an oral vaccine could be mixed with feed and may offer a cheap and less labour intensive alternative to inoculation with the additional advantage that no cooling chain would be required for vaccine transport and storage. Copyright © 2015 The

  12. Biocontrol activity of a cold-adapted yeast from Tibet against gray mold in cherry tomato and its action mechanism.

    Science.gov (United States)

    Hu, Hao; Wisniewski, Michael E; Abdelfattah, Ahmed; Zheng, Xiaodong

    2017-07-01

    Cold-adapted biocontrol yeast was selected from four yeast isolates from Tibet against gray mold of cherry tomato in cold storage. The strain numbered LB2 showed the best biocontrol activity and identified as Cryptococcus laurentii. Competition for nutrient, space, and induced fruit resistance was also its antagonistic mechanism. Compared with C. laurentii from sea-level place, the reason why LB2 had a better biocontrol activity was studied. More trehalose and proline in cell of LB2 made it exhibit a better cellular activity at low temperature, such as higher population dynamics in the wounds of cherry tomato and more biocontrol-related enzyme secretion, chitinase and β-glucanase. The better oxidative stress tolerance was another characteristic of LB2. Maybe because of the ideal culture condition, there was no obvious difference between these two yeasts in the growth in vitro test at low temperature. Although the same phenomenon existed in the low pH stress test, LB2 still had higher cell concentration under this stress. Comparative transcriptomics method was also applied to analyze the cell activity of LB2 and C. laurentii at different temperatures. The results showed that more active response in the intracellular structure and intracellular metabolic process to cold temperature made LB2 had a better activity. The present study indicated a possibility to select cold-adapted biocontrol yeast from Tibet and also showed its primary action mechanism.

  13. Anethole potentiates dodecanol's fungicidal activity by reducing PDR5 expression in budding yeast.

    Science.gov (United States)

    Fujita, Ken-Ichi; Ishikura, Takayuki; Jono, Yui; Yamaguchi, Yoshihiro; Ogita, Akira; Kubo, Isao; Tanaka, Toshio

    2017-02-01

    trans-Anethole (anethole), a major component of anise oil, has a broad antimicrobial spectrum and a weaker antimicrobial potency than other available antibiotics. When combined with polygodial, nagilactone E, and n-dodecanol, anethole has been shown to exhibit synergistic antifungal activity against a budding yeast, Saccharomyces cerevisiae, and a human opportunistic pathogenic yeast, Candida albicans. However, the mechanism underlying this synergistic effect of anethole has not been characterized. We studied this mechanism using dodecanol-treated S. cerevisiae cells and focusing on genes related to multidrug efflux. Although dodecanol transiently reduced the number of colony forming units, this recovered to levels similar to those of untreated cells with continued incubation beyond 24h. Reverse transcription polymerase chain reaction analysis revealed overexpression of an ATP-binding cassette (ABC) transporter gene, PDR5, in addition to a slight increase in PDR11, PDR12, and PDR15 transcriptions in dodecanol-treated cells. In the presence of anethole, these effects were attenuated and the fungicidal activity of dodecanol was extended. Dodecanol showed longer lasting fungicidal activity against a Δpdr5. In addition, Δpdr3 and Δlge1, lack transcription factors of PDR5 and PDR3, were partly and completely susceptible to dodecanol, respectively. Furthermore, combination of anethole with fluconazole was also found to exhibit synergy on C. albicans. These results indicated that although anethole reduced the transcription of several transporters, PDR5 expression was particularly relevant to dodecanol efflux. Anethole is expected to be a promising candidate drug for the inhibition of efflux by reducing the transcription of several ABC transporters. Copyright © 2016 Elsevier B.V. All rights reserved.

  14. Investigation of antineoplastic activity of chewing tablets based on dry oat extract and quercetin

    Directory of Open Access Journals (Sweden)

    Ярослав Ростиславович Андрійчук

    2015-07-01

    Full Text Available One of the main goals of domestic pharmaceutical science is development of new medicines. Thus, new tablet drug was created based on dry oat extract and quercetin. Investigation of antineoplastic activity was performed. Antineoplastic activity of investigational drug based on dry oat extract and quercetin was experimentally proved.

  15. Effects of Different Drying Methods on the Antioxidant Activities of Leaves and Berries of Cayratia trifolia

    International Nuclear Information System (INIS)

    Rabeta, M.S.; Lin, S.P.

    2015-01-01

    This study aimed to assess the effects of fresh, thermal drying method (vacuum oven drying), and nonthermal drying method (freeze drying) on the antioxidant activities of leaves and berries of Cayratia trifolia using ferric reducing antioxidant power (FRAP) and 1,1-diphenyl-1-picrylhydrazyl radical scavenging capacity (DPPH) assays. The total phenolic content (TPC) and flavonoid content (TFC) of the leaves and berries of C. trifolia were also measured. Based on the results obtained, the TPC, TFC, and antioxidant activities of the leaves and berries were arranged in the following order: freeze-dried sample with methanol extraction > vacuum-dried sample with methanol extraction > freeze-dried sample with water extraction > vacuum-dried sample with water extraction > fresh sample with methanol extraction > fresh sample with water extraction. The results showed a significant difference (p<0.05) between the fresh and dried samples. In conclusion, freeze drying was found to be a good method for maintaining TPC, TFC, and antioxidant activities by FRAP and DPPH methods in the leaves and berries of C. trifolia. (author)

  16. Antimicrobial Activity of Endemic Herbs from Tangkahan Conservation Forest North Sumatera to Bacteria and Yeast

    Directory of Open Access Journals (Sweden)

    KIKI NURTJAHJA

    2013-12-01

    Full Text Available Tangkahan Conservation Forest in Karo County, North Sumatera has high biodiversity of endemic herbs. Many species of the wild herbs are well known used as traditional medicine not only by local people but also by people out of the area. The methanol extract of the medicinal wild herbs in Tangkahan Conservation Forest, Karo County to relief skin diseases caused by bacteria and fungi never been studied medically. The antimicrobial activity leave extract of the medicinal herbs to pathogenic microorganisms are studied. The leaves extract of kembu-kembu (Callicarpa candicans, rintih bulung (Piper muricatum, cep-cepan (Castanopsis costata, and sereh kayu (Eugenia grandis, has antimicrobial to bacteria (Bacillus sp., Escherichia coli, Serratia marcescens, Staphylococcus aureus and yeast (Candida albicans. Toxicity assay of these plants by brine shrimp method using Artemia salina indicates that cep-cepan dan sereh kayu have lethal concentration higher than kembu-kembu and rintih bulung.

  17. Killer toxin from a novel killer yeast Pichia kudriavzevii RY55 with idiosyncratic antibacterial activity.

    Science.gov (United States)

    Bajaj, Bijender Kumar; Raina, Sandeepu; Singh, Satbir

    2013-08-01

    The killer phenomenon of yeast may have technological implications in many areas like beverage fermentation, food technology, biological control in agriculture, and in medicine. In the present study the killer phenomenon in Pichia kudriavzevii (P. kudriavzevii RY55) is being reported for the first time. The P. kudriavzevii RY55 toxin exhibited excellent antibacterial activity against several pathogens of human health significance such as Escherichia coli, Enterococcus faecalis, Klebsiella sp., Staphylococcus aureus, Pseudomonas aeruginosa and Pseudomonas alcaligenes. Killer toxin was purified to homogeneity by using ammonium sulphate precipitation and ion exchange chromatography and characterized for few properties. P. kudriavzevii RY55 killer toxin may be of vast significance in the development of novel antimicrobial chemotherapeutic agents, new bio-based safer candidates for food preservation and biocontrol, and starter cultures for fermentation industries. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. Yeast Breads. Learning Activity Pack and Instructor's Guide 5.15a. Commercial Foods and Culinary Arts Competency-Based Series. Section 5: Basic Food Preparation.

    Science.gov (United States)

    Florida State Univ., Tallahassee. Center for Studies in Vocational Education.

    This document consists of a learning activity packet (LAP) for the student and an instructor's guide for the teacher. The LAP is intended to acquaint occupational home economics students with yeast breads and their ingredients. Illustrated information sheets and learning activities are provided in these areas: yeast breads and their ingredients,…

  19. Multiple determinants controlling activation of yeast replication origins late in S phase.

    Science.gov (United States)

    Friedman, K L; Diller, J D; Ferguson, B M; Nyland, S V; Brewer, B J; Fangman, W L

    1996-07-01

    Analysis of a 131-kb segment of the left arm of yeast chromosome XIV beginning 157 kb from the telomere reveals four highly active origins of replication that initiate replication late in S phase. Previous work has shown that telomeres act as determinants for late origin activation. However, at least two of the chromosome XIV origins maintain their late activation time when located on large circular plasmids, indicating that late replication is independent of telomeres. Analysis of the replication time of plasmid derivatives containing varying amounts of chromosome XIV DNA show that a minimum of three chromosomal elements, distinct from each tested origin, contribute to late activation time. These late determinants are functionally equivalent, because duplication of one set of contributing sequences can compensate for the removal of another set. Furthermore, insertion of an origin that is normally early activated into this domain results in a shift to late activation, suggesting that the chromosome XIV origins are not unique in their ability to respond to the late determinants.

  20. Phytase-active yeasts from grain-based food and beer.

    Science.gov (United States)

    Nuobariene, L; Hansen, A S; Jespersen, L; Arneborg, N

    2011-06-01

    To screen yeast strains isolated from grain-based food and beer for phytase activity to identify high phytase-active strains. The screening of phytase-positive strains was carried out at conditions optimal for leavening of bread dough (pH 5·5 and 30°C), in order to identify strains that could be used for the baking industry. Two growth-based tests were used for the initial testing of phytase-active strains. Tested strains belonged to six species: Saccharomyces cerevisiae, Saccharomyces pastorianus, Saccharomyces bayanus, Kazachstania exigua (former name Saccharomyces exiguus), Candida krusei (teleomorph Issachenkia orientalis) and Arxula adeninivorans. On the basis of initial testing results, 14 strains were selected for the further determination of extracellular and intracellular (cytoplasmic and/or cell-wall bound) phytase activities. The most prominent strains for extracellular phytase production were found to be S. pastorianus KVL008 (a lager beer strain), followed by S. cerevisiae KVL015 (an ale beer strain) and C. krusei P2 (isolated from sorghum beer). Intracellular phytase activities were relatively low in all tested strains. Herein, for the first time, beer-related strains of S. pastorianus and S. cerevisiae are reported as phytase-positive strains. The high level of extracellular phytase activity by the strains mentioned previously suggests them to be strains for the production of wholemeal bread with high content of bioavailable minerals. © 2011 The Authors. Journal of Applied Microbiology © 2011 The Society for Applied Microbiology.

  1. Esterase Active in Polar Organic Solvents from the Yeast Pseudozyma sp. NII 08165

    Directory of Open Access Journals (Sweden)

    Deepthy Alex

    2014-01-01

    Full Text Available Esterases/lipases active in water miscible solvents are highly desired in biocatalysis where substrate solubility is limited and also when the solvent is desired as an acyl acceptor in transesterification reactions, as with the case of biodiesel production. We have isolated an esterase from the glycolipid producing yeast-Pseudozyma sp. NII 08165 which in its crude form was alkali active, thermo stable, halo tolerant and also capable of acting in presence of high methanol concentration. The crude enzyme which maintained 90% of its original activity after being treated at 70°C was purified and the properties were characterized. The partially purified esterase preparation had temperature and pH optima of 60°C and 8.0 respectively. The enzyme retained almost complete activity in presence of 25% methanol and 80% activity in the same strength of ethanol. Conditions of enzyme production were optimized, which lead to 9 fold increase in the esterase yield. One of the isoforms of the enzyme LIP1 was purified to homogeneity and characterized. Purified LIP1 had a Km and Vmax of 0.01 and 1.12, respectively. The purified esterase lost its thermo and halo tolerance but interestingly, retained 97% activity in methanol.

  2. Kinetics, biocompounds, antioxidant activity, and sensory attributes of quinces as affected by drying method.

    Science.gov (United States)

    Szychowski, Przemysław J; Lech, Krzysztof; Sendra-Nadal, Esther; Hernández, Francisca; Figiel, Adam; Wojdyło, Aneta; Carbonell-Barrachina, Ángel A

    2018-07-30

    Quinces are attracting interest due to their health and nutritional benefits. Drying kinetics, bioactive compounds, antioxidant activity, and the main sensory parameters were determined in dried quinces, cultivar Leskovač, as affected by the drying method. The highest total polyphenols content was observed in dried samples obtained after freeze drying and convective drying at 50 °C. The best drying treatment, considering only sensory attributes, was vacuum-microwave drying at 480 W, because it led to intermediate dark color and high intensities of basic tastes and key flavor attributes. The studied parameters were finally used to recommend convective drying at 60 °C as the most appropriate drying method for quinces, because it had a high content of total phenolic compounds (2nd best treatment out of 10), a good sensory profile, was cheap, and caused no negative effects on nutritional or sensory parameters; the only disadvantage was its long drying time. Copyright © 2018 Elsevier Ltd. All rights reserved.

  3. Yeast carboxypeptidase Y requires glycosylation for efficient intracellular transport, but not for vacuolar sorting, in vivo stability, or activity

    DEFF Research Database (Denmark)

    Winther, Jakob R.; Stevens, T H; Kielland-Brandt, Morten

    1991-01-01

    Functions of the carbohydrate side chains of the yeast vacuolar enzyme carboxypeptidase Y (CPY) were investigated by removal, through site-directed mutagenesis, of the sequences which act as signals for N-linked glycosylation. The mutant forms of the enzyme were analysed with respect to activity...

  4. Characterization of active reverse transcriptase and nucleoprotein complexes of the yeast retrotransposon Ty3 in vitro.

    Science.gov (United States)

    Cristofari, G; Gabus, C; Ficheux, D; Bona, M; Le Grice, S F; Darlix, J L

    1999-12-17

    Human immunodeficiency virus (HIV) and the distantly related yeast Ty3 retrotransposon encode reverse transcriptase (RT) and a nucleic acid-binding protein designated nucleocapsid protein (NCp) with either one or two zinc fingers, required for HIV-1 replication and Ty3 transposition, respectively. In vitro binding of HIV-1 NCp7 to viral 5' RNA and primer tRNA(3)(Lys) catalyzes formation of nucleoprotein complexes resembling the virion nucleocapsid. Nucleocapsid complex formation functions in viral RNA dimerization and tRNA annealing to the primer binding site (PBS). RT is recruited in these nucleoprotein complexes and synthesizes minus-strand cDNA initiated at the PBS. Recent results on yeast Ty3 have shown that the homologous NCp9 promotes annealing of primer tRNA(i)(Met) to a 5'-3' bipartite PBS, allowing RNA:tRNA dimer formation and initiation of cDNA synthesis at the 5' PBS (). To compare specific cDNA synthesis in a retrotransposon and HIV-1, we have established a Ty3 model system comprising Ty3 RNA with the 5'-3' PBS, primer tRNA(i)(Met), NCp9, and for the first time, highly purified Ty3 RT. Here we report that Ty3 RT is as active as retroviral HIV-1 or murine leukemia virus RT using a synthetic template-primer system. Moreover, and in contrast to what was found with retroviral RTs, retrotransposon Ty3 RT was unable to direct cDNA synthesis by self-priming. We also show that Ty3 nucleoprotein complexes were formed in vitro and that the N terminus of NCp9, but not the zinc finger, is required for complex formation, tRNA annealing to the PBS, RNA dimerization, and primer tRNA-directed cDNA synthesis by Ty3 RT. These results indicate that NCp9 chaperones bona fide cDNA synthesis by RT in the yeast Ty3 retrotransposon, as illustrated for NCp7 in HIV-1, reinforcing the notion that Ty3 NCp9 is an ancestor of HIV-1 NCp7.

  5. Optimization of oligomeric enzyme activity in ionic liquids using Rhodotorula glutinis yeast phenylalanine ammonia lyase.

    Science.gov (United States)

    Barron, Christiaan C; Sponagle, Brandon J D; Arivalagan, Pugazhendhi; D'Cunha, Godwin B

    2017-01-01

    Phenylalanine ammonia lyase (E.C.4.3.1.24, PAL) activity of Rhodotorula glutinis yeast has been demonstrated in four commonly used ionic liquids. PAL forward reaction was carried out in 1-butyl-3-methylimidazolium methyl sulfate ([BMIM][MeSO 4 ]), 1-butyl-3-methylimidazolium tetrafluoroborate ([BMIM][BF 4 ]), 1-butyl-3-methylimidazolium hexafluorophosphate ([BMIM][PF 6 ]) and 1-butyl-3-methylimidazolium lactate ([BMIM][lactate]). Our experiments have revealed that PAL is catalytically active in ionic liquids and the enzyme activity in ([BMIM][PF 6 ]) is comparable to that obtained in aqueous buffer medium. Different conditions were optimized for maximal PAL forward activity including time of incubation (30.0min) L -phenylalanine substrate concentration (30.0mM), nature of buffer (50.0mM Tris-HCl), pH (9.0), temperature (37°C), and speed of agitation (100 rev min -1 ). Under these optimized conditions, about 83% conversion of substrate to product was obtained for the PAL forward reaction that was determined using UV spectroscopy at 290nm. PAL reverse reaction in ([BMIM][PF 6 ]) was determined spectrophotometrically at 520nm; and about 59% substrate conversion was obtained. This data provides further knowledge in enzyme biocatalysis in non-aqueous media, and may be of importance when studying the function of other oligomeric/multimeric proteins and enzymes in ionic liquids. Copyright © 2016 Elsevier Inc. All rights reserved.

  6. Therapeutic activity of a Saccharomyces cerevisiae-based probiotic and inactivated whole yeast on vaginal candidiasis.

    Science.gov (United States)

    Pericolini, Eva; Gabrielli, Elena; Ballet, Nathalie; Sabbatini, Samuele; Roselletti, Elena; Cayzeele Decherf, Amélie; Pélerin, Fanny; Luciano, Eugenio; Perito, Stefano; Jüsten, Peter; Vecchiarelli, Anna

    2017-01-02

    Vulvovaginal candidiasis is the most prevalent vaginal infection worldwide and Candida albicans is its major agent. Vulvovaginal candidiasis is characterized by disruption of the vaginal microbiota composition, as happens following large spectrum antibiotic usage. Recent studies support the effectiveness of oral and local probiotic treatment for prevention of recurrent vulvovaginal candidiasis. Saccharomyces cerevisiae is a safe yeast used as, or for, the production of ingredients for human nutrition and health. Here, we demonstrate that vaginal administration of probiotic Saccharomyces cerevisiae live yeast (GI) and, in part, inactivated whole yeast Saccharomyces cerevisiae (IY), used as post-challenge therapeutics, was able to positively influence the course of vaginal candidiasis by accelerating the clearance of the fungus. This effect was likely due to multiple interactions of Saccharomyces cerevisiae with Candida albicans. Both live and inactivated yeasts induced coaggregation of Candida and consequently inhibited its adherence to epithelial cells. However, only the probiotic yeast was able to suppress some major virulence factors of Candida albicans such as the ability to switch from yeast to mycelial form and the capacity to express several aspartyl proteases. The effectiveness of live yeast was higher than that of inactivated whole yeast suggesting that the synergy between mechanical effects and biological effects were dominant over purely mechanical effects. The protection of epithelial cells to Candida-induced damage was also observed. Overall, our data show for the first time that Saccharomyces cerevisiae-based ingredients, particularly the living cells, can exert beneficial therapeutic effects on a widespread vaginal mucosal infection.

  7. Effect Carrier Agent Formulation in Drying Rate and Antioxidant Activity of Roselle Extract

    Directory of Open Access Journals (Sweden)

    Utari Febiani Dwi

    2018-01-01

    Full Text Available Roselle (Hibiscus sabdarifa L contains anthocyanins as the natural colorant and antioxidant. Drying the roselle extract was aims to produce the dry product that easy consumption as antioxidant. The carrier agent was added in roselle extract to improve the drying rate and maintain the nutritional value. This research studied the effect of carrier agent in drying rate and antioxidant activity. The method consists of two step involving roselle extraction using ultrasonic and the drying process. The roselle extraction by ultrasonic use the water as the solvent. The carrier agent (0%,5%,10% of maltodextrin was added in roselle extract. The mixture was then dried in tray dryer dehumidification using zeolite in drying temperature 50,60, and 70⁰C. As the response, the moisture content was observed by gravimetry every 15 minutes for 150 minutes. The result showed that Page model was fitted to determine the constant of drying rate. Higher concentration of carrier agent enhanced the moisture evaporation process. Based on the DPPH analysis, the degradation of antioxidant activity in temperature 70⁰C was 2.14 times higher than in temperature 50⁰C. As the conclusion, addition of maltodextrin can speed up the drying process and retain the antioxidant activity of.

  8. Effect of drying techniques on the retention of antioxidant activities of Saskatoon berries

    Directory of Open Access Journals (Sweden)

    Pranabendu Mitra

    2013-10-01

    Full Text Available The main objective of this research was to compare the retention of antioxidant activity and total anthocyanin content of Saskatoon berries dried by freeze drying, microwave-vacuum drying, thin layer hot air drying and vacuum drying. Antioxidant activity of berry samples was determined by DPPH radical scavenging and ABTS radical scavenging, and the pH differential method was used to determine total anthocyanin content of the berry samples. The results showed that the freeze dried Saskatoon berries exhibited the highest retention of anthocyanin and antioxidant activity among the dried samples, followed by microwave-vacuum dried berries, thin layer hot air dried berries and vacuum dried berries. There were significant differences between the berry samples at P<0.05.  DPPH radical scavenging and ABTS radical scavenging were correlated linearly with an R2 value of 0.99 at P<0.05 showing their effectiveness for the determination of the antioxidant activity of the Saskatoon berries. However, the DPPH radical scavenging assay was more effective than the ABTS radical scavenging assay. The results also showed that antioxidant activity of the berries was highly correlated with the total anthocyanin content of the fruit. The reduction of anthocyanin in dried berry samples was linearly correlated with the reduction of DPPH radical scavenging with an R2 value of 0.97 at P<0.05 and, also, linearly correlated with the reduction of ABTS radical scavenging with an R2 value of 0.88 at P<0.05.

  9. Active Yeast Telomerase Shares Subunits with Ribonucleoproteins RNase P and RNase MRP.

    Science.gov (United States)

    Lemieux, Bruno; Laterreur, Nancy; Perederina, Anna; Noël, Jean-François; Dubois, Marie-Line; Krasilnikov, Andrey S; Wellinger, Raymund J

    2016-05-19

    Telomerase is the ribonucleoprotein enzyme that replenishes telomeric DNA and maintains genome integrity. Minimally, telomerase activity requires a templating RNA and a catalytic protein. Additional proteins are required for activity on telomeres in vivo. Here, we report that the Pop1, Pop6, and Pop7 proteins, known components of RNase P and RNase MRP, bind to yeast telomerase RNA and are essential constituents of the telomerase holoenzyme. Pop1/Pop6/Pop7 binding is specific and involves an RNA domain highly similar to a protein-binding domain in the RNAs of RNase P/MRP. The results also show that Pop1/Pop6/Pop7 function to maintain the essential components Est1 and Est2 on the RNA in vivo. Consistently, addition of Pop1 allows for telomerase activity reconstitution with wild-type telomerase RNA in vitro. Thus, the same chaperoning module has allowed the evolution of functionally and, remarkably, structurally distinct RNPs, telomerase, and RNases P/MRP from unrelated progenitor RNAs. Copyright © 2016 Elsevier Inc. All rights reserved.

  10. Deliverable D2.4: Status of Dry Electrode Development Activity

    NARCIS (Netherlands)

    Mihajlovic, V.; Garcia Molina, G.

    2010-01-01

    The goal of dry electrode development activity within the WP2 is tobuild a dry electrode prototype for brain wave sensing that is comfortable for the user and provides sufficient signal quality. The electrodes are to be utilized in BCI applications, namely Steady-StateVisually Evoked Potential

  11. Antifungal activity of four honeys of different types from Algeria against pathogenic yeast: Candida albicans and Rhodotorula sp.

    OpenAIRE

    Ahmed Moussa; Djebli Noureddine; Aissat Saad; Meslem Abdelmelek; Benhalima Abdelkader

    2012-01-01

    Objective: To evaluate the antifungal activity of four honeys of different types from Algeria against pathogenic yeast i.e. Candida albicans (C. albicans) and Rhodotorula sp. Methods: Four Algeria honeys of different botanical origin were analyzed to test antifungal effect against C. albicans, and Rhodotorula sp. Different concentrations (undiluted, 10%, 30%, 50% and 70% w/v) of honey were studied in vitro for their antifugal activity using C. albicans and Rhodotorula sp. as fungal strains...

  12. Arrhenius activation energy of damage to catalase during spray-drying.

    Science.gov (United States)

    Schaefer, Joachim; Lee, Geoffrey

    2015-07-15

    The inactivation of catalase during spray-drying over a range of outlet gas temperatures could be closely represented by the Arrhenius equation. From this an activation energy for damage to the catalase could be calculated. The close fit to Arrhenius suggests that the thermally-induced part of inactivation of the catalase during the complex drying and particle-formation processes takes place at constant temperature. These processes are rapid compared with the residence time of the powder in the collecting vessel of the cyclone where dried catalase is exposed to a constant temperature equal to approximately the drying gas outlet temperature. A lower activation energy after spray drying with the ultrasonic nozzle was found than with the 2-fluid nozzle under otherwise identical spray drying conditions. It is feasible that the ultrasonic nozzle when mounted in the lid of the spray dryer heats up toward the drying gas inlet temperature much more that the air-cooled 2-fluid nozzle. Calculation of the Arrhenius activation energy also showed how the stabilizing efficacy of trehalose and mannitol on the catalase varies in strength across the range of drying gas inlet and outlet temperatures examined. Copyright © 2015 Elsevier B.V. All rights reserved.

  13. Zymography Methods to Simultaneously Analyze Superoxide Dismutase and Catalase Activities: Novel Application for Yeast Species Identification.

    Science.gov (United States)

    Gamero-Sandemetrio, Esther; Gómez-Pastor, Rocío; Matallana, Emilia

    2017-01-01

    We provide an optimized protocol for a double staining technique to analyze superoxide dismutase enzymatic isoforms Cu-Zn SOD (Sod1) and Mn-SOD (Sod2) and catalase in the same polyacrylamide gel. The use of NaCN, which specifically inhibits yeast Sod1 isoform, allows the analysis of Sod2 isoform while the use of H 2 O 2 allows the analysis of catalase. The identification of a different zymography profiling of SOD and catalase isoforms in different yeast species allowed us to propose this technique as a novel yeast identification and classification strategy.

  14. RPA facilitates telomerase activity at chromosome ends in budding and fission yeasts.

    Science.gov (United States)

    Luciano, Pierre; Coulon, Stéphane; Faure, Virginie; Corda, Yves; Bos, Julia; Brill, Steven J; Gilson, Eric; Simon, Marie-Noelle; Géli, Vincent

    2012-04-18

    In Saccharomyces cerevisiae, the telomerase complex binds to chromosome ends and is activated in late S-phase through a process coupled to the progression of the replication fork. Here, we show that the single-stranded DNA-binding protein RPA (replication protein A) binds to the two daughter telomeres during telomere replication but only its binding to the leading-strand telomere depends on the Mre11/Rad50/Xrs2 (MRX) complex. We further demonstrate that RPA specifically co-precipitates with yKu, Cdc13 and telomerase. The interaction of RPA with telomerase appears to be mediated by both yKu and the telomerase subunit Est1. Moreover, a mutation in Rfa1 that affects both the interaction with yKu and telomerase reduces the dramatic increase in telomere length of a rif1Δ, rif2Δ double mutant. Finally, we show that the RPA/telomerase association and function are conserved in Schizosaccharomyces pombe. Our results indicate that in both yeasts, RPA directly facilitates telomerase activity at chromosome ends.

  15. Evidence for Multiple Mediator Complexes in Yeast Independently Recruited by Activated Heat Shock Factor.

    Science.gov (United States)

    Anandhakumar, Jayamani; Moustafa, Yara W; Chowdhary, Surabhi; Kainth, Amoldeep S; Gross, David S

    2016-07-15

    Mediator is an evolutionarily conserved coactivator complex essential for RNA polymerase II transcription. Although it has been generally assumed that in Saccharomyces cerevisiae, Mediator is a stable trimodular complex, its structural state in vivo remains unclear. Using the "anchor away" (AA) technique to conditionally deplete select subunits within Mediator and its reversibly associated Cdk8 kinase module (CKM), we provide evidence that Mediator's tail module is highly dynamic and that a subcomplex consisting of Med2, Med3, and Med15 can be independently recruited to the regulatory regions of heat shock factor 1 (Hsf1)-activated genes. Fluorescence microscopy of a scaffold subunit (Med14)-anchored strain confirmed parallel cytoplasmic sequestration of core subunits located outside the tail triad. In addition, and contrary to current models, we provide evidence that Hsf1 can recruit the CKM independently of core Mediator and that core Mediator has a role in regulating postinitiation events. Collectively, our results suggest that yeast Mediator is not monolithic but potentially has a dynamic complexity heretofore unappreciated. Multiple species, including CKM-Mediator, the 21-subunit core complex, the Med2-Med3-Med15 tail triad, and the four-subunit CKM, can be independently recruited by activated Hsf1 to its target genes in AA strains. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

  16. Effect of freeze-drying on the antioxidant compounds and antioxidant activity of selected tropical fruits.

    Science.gov (United States)

    Shofian, Norshahida Mohamad; Hamid, Azizah Abdul; Osman, Azizah; Saari, Nazamid; Anwar, Farooq; Dek, Mohd Sabri Pak; Hairuddin, Muhammad Redzuan

    2011-01-01

    The effects of freeze-drying on antioxidant compounds and antioxidant activity of five tropical fruits, namely starfruit (Averrhoa carambola L.), mango (Mangifera indica L.), papaya (Carica papaya L.), muskmelon (Cucumis melo L.), and watermelon Citruluss lanatus (Thunb.) were investigated. Significant (p dried fruit samples, except muskmelon. There was no significant (p > 0.05) change, however, observed in the ascorbic acid content of the fresh and freeze-dried fruits. Similarly, freeze-drying did not exert any considerable effect on β-carotene concentration of fruits, except for mango and watermelon, where significantly (p dried fruits. Overall, in comparison to β-carotene and ascorbic acid, a good correlation was established between the result of TPC and antioxidant assays, indicating that phenolics might have been the dominant compounds contributing towards the antioxidant activity of the fruits tested.

  17. Activity release during the dry storage of fuel assemblies

    International Nuclear Information System (INIS)

    Valentine, M.K.; Fettel, W.; Gunther, H.

    1991-01-01

    This paper reports that wet storage is the predominant storage method in the USA for spent fuel assemblies. Nevertheless, most utilities have stretched their storage capacities and several reactors will lose their full-core reserve in the 90's. A great variety of out-of-pool storage methods already exist, including the FUELSTOR vault-type dry storage concept. A FUELSTOR vault relies on double containment of the spent fuel (intact cladding as the primary containment and sealing of assemblies in canisters filled with an inert gas as the secondary containment) to reduce radiation levels at the outside wall of the vault to less than site boundary levels. Investigation of accident scenarios reveals that radiation release limits are only exceeded following complete failure of all canisters and simultaneous cladding breach for more than 40% of the rods (or for more than 1% of failed rods if massive fuel oxidation occurs following cladding failure). Such failures are considered highly improbable. Thus, it can be concluded that this type of dry storage is safe and individual canister monitoring is not required in the facility

  18. Determination of yeast killer activity in fermenting sugarcane juice using selected ethanol-making strains

    Directory of Open Access Journals (Sweden)

    Sandra Regina Ceccato-Antonini

    2004-03-01

    Full Text Available Twenty-four yeasts out of 342 isolated from the fermentative process showed killer activity and three of them were selected for the fermentative efficiency evaluation in batch system with cell recycle, flask and fermentor experiments. The selected three killer strains did not present similar results to those of pressed (baking yeast concerning ethanol (0.07-0.18; 0.12-0.20; 0.10-0.13; 0.22-0.25 g/g, respectively and biomass (0.19-0.26; 0.33-0.39; 0.13-0.27; 0.47-0.61 g/g, respectively yields and fermentative efficiency (12.3-36.3; 21.0-40.0; 19.3-26.3; 47.6-54.0 %, respectively in sugarcane juice, in flasks. In fermentor, similar behaviour was observed. However, the selected strains showed high cellular viability and killer activity (using cell-free filtrate along the fermentative cycles, in spite of the unfavourable conditions of the medium, like high pH variation of the medium (from 5.5-6.0 to 3.0-4.0, low aeration and higher temperature (30º C, which were not the ideal ones for the production/activity of killer toxins. A Pichia strain (CCA 510 showed the best results among the killer yeasts tested, exhibiting a killer activity against 92% of isolated fermentative yeasts of the process and against the pressed (baking ferment. It also demonstrated killer activity (using crude toxin preparation at higher temperatures (38ºC and low pH (4.0 after 72 hours of incubation, under proliferative and non-proliferative conditions. The results indicated that the killer activity should be a characteristic to be looked for in the strain selection for ethanolic fermentation, beside other important productivity-based characteristics, since it assure the permanence of the selected strain during the process.A atividade 'killer' poderia garantir às leveduras fermentativas uma vantagem competitiva sobre outras linhagens durante a fermentação etanólica, no entanto, pouco se sabe sobre o papel do sistema 'killer' nesse tipo de fermentação alcoólica. A sele

  19. GC-rich DNA elements enable replication origin activity in the methylotrophic yeast Pichia pastoris.

    Science.gov (United States)

    Liachko, Ivan; Youngblood, Rachel A; Tsui, Kyle; Bubb, Kerry L; Queitsch, Christine; Raghuraman, M K; Nislow, Corey; Brewer, Bonita J; Dunham, Maitreya J

    2014-03-01

    The well-studied DNA replication origins of the model budding and fission yeasts are A/T-rich elements. However, unlike their yeast counterparts, both plant and metazoan origins are G/C-rich and are associated with transcription start sites. Here we show that an industrially important methylotrophic budding yeast, Pichia pastoris, simultaneously employs at least two types of replication origins--a G/C-rich type associated with transcription start sites and an A/T-rich type more reminiscent of typical budding and fission yeast origins. We used a suite of massively parallel sequencing tools to map and dissect P. pastoris origins comprehensively, to measure their replication dynamics, and to assay the global positioning of nucleosomes across the genome. Our results suggest that some functional overlap exists between promoter sequences and G/C-rich replication origins in P. pastoris and imply an evolutionary bifurcation of the modes of replication initiation.

  20. GC-rich DNA elements enable replication origin activity in the methylotrophic yeast Pichia pastoris.

    Directory of Open Access Journals (Sweden)

    Ivan Liachko

    2014-03-01

    Full Text Available The well-studied DNA replication origins of the model budding and fission yeasts are A/T-rich elements. However, unlike their yeast counterparts, both plant and metazoan origins are G/C-rich and are associated with transcription start sites. Here we show that an industrially important methylotrophic budding yeast, Pichia pastoris, simultaneously employs at least two types of replication origins--a G/C-rich type associated with transcription start sites and an A/T-rich type more reminiscent of typical budding and fission yeast origins. We used a suite of massively parallel sequencing tools to map and dissect P. pastoris origins comprehensively, to measure their replication dynamics, and to assay the global positioning of nucleosomes across the genome. Our results suggest that some functional overlap exists between promoter sequences and G/C-rich replication origins in P. pastoris and imply an evolutionary bifurcation of the modes of replication initiation.

  1. Effect of microwave drying and oven drying on the water activity, color, phenolic compounds content and antioxidant activity of coconut husk (Cocos nucifera L.).

    Science.gov (United States)

    Valadez-Carmona, Lourdes; Cortez-García, Rosa María; Plazola-Jacinto, Carla Patricia; Necoechea-Mondragón, Hugo; Ortiz-Moreno, Alicia

    2016-09-01

    The coconut ( Cocos nucifera L.) husk is basically composed by fiber and pith material and remained under-utilized. This is an important source of phenolic compounds that could be used as functional ingredients. The aim of this study was to determine the effect of: oven-drying (OD) and microwave drying (MD), on the water activity, color, phenolic compound content and antioxidant activity of coconut husk. The OD was performed at 60 °C for 12 h and MD was performed at 900 W for 10 min. The total phenolic content (TPC) in fresh coconut husk was 64.2 mg GAE/g dry wt and significant higher than observed after OD and MD of 35.8 and 45.5 mg GAE/g dry wt, respectively. Ten phenols were identified in fresh and dehydrated coconut husks. The husk MD showed an increase in the content of gallic, 4-hydroxybenzoic, ferulic and syringic acids and epicatechin compared with the fresh; while coconut husk OD and MD, showed a decrease in the content of vanillic acid, vanillin, catequin and kaempferol. The antioxidant activity decreased after both OD and MD. However, MD resulted in a better antioxidant activity in husk than OD. MD of husk resulted into better retention of preserved color, TPC and TFC than OD.

  2. Anti-inflammatory and antinociceptive activities of Phyllanthus niruri spray-dried standardized extract

    Directory of Open Access Journals (Sweden)

    Cínthia R. C. Porto

    2013-02-01

    Full Text Available Phyllanthus niruri L., Euphorbiaceae, spray-dried standardized extract was studied for its anti-inflammatory and antinociceptive activities in adult albino rats and mice. The anti-inflammatory effect of spray-dried standardized extract was observed in carrageenan-induced paw edema and thioglycolate-induced leukocyte migration, while antinociceptive effects were observed using Randall & Selitto, tail flick, and hot plate tests. This study showed that intraperitoneal spray-dried standardized extract at 100, 200, 800, or 1600 mg/kg reduced the vascular response in the inflammatory process of paw edema induced by 1% carrageenan. Oral spray-dried standardized extract at 100 or 200 mg/kg inhibited leukocyte migration to the site of inflammation induced by 3% thioglycolate. In rats, at 100 and 200 mg/kg intraperitoneally, the extract exhibited a marked peripheral analgesic effect in a Randall & Selitto assay and showed significant central analgesic activity in a hot plate and tail flick assay. In conclusion, this study suggested that Phyllanthus niruri spray-dried standardized extract has potent inflammatory and antinociceptive activities and that these activities are not modified by standard drying process, making it feasible to use the dry extract standardized to obtain a phytotherapic preparation and thus validating its use for the treatment of pain and inflammation disorders.

  3. Auxotrophy-stimulated sensitivity to quaternary ammonium salts and its relation to active transport in yeast

    International Nuclear Information System (INIS)

    Lachowicz, T.M.; Oblak, E.; Piatkowski, J.

    1992-01-01

    In previous studies we have observed that auxotrophic mutants of yeast were much more sensitive to quaternary ammonium salts than the corresponding isogenic wild type strains. The super sensitivity of the auxotrophs seems to be a characteristic feature of yeast and yeast-like microorganisms: the level of sensitivity of the quaternary ammonium salts of the bacterial auxotrophs and their original prototrophic forms appeared to be the same. The super sensitivity of yeast auxotrophs disappeared on minimal media with ammonium as a nitrogen source. In this report there are presented the data indicating that enrichment of the minimal medium with arginine restores the super sensitivity of auxotrophic yeast mutants to the quaternary ammonium salts. The results of amino-acid transport into the auxotrophic yeast cells treated with a quaternary ammonium salt in the presence and absence of arginine are given. A working hypothesis of the mechanism of these salts action as a specific inhibition of nutrient transport is discussed. (author). 19 refs, 3 figs, 8 figs

  4. Base-modified GDP-mannose derivatives and their substrate activity towards a yeast mannosyltransferase.

    Science.gov (United States)

    Collier, Alice; Wagner, Gerd K

    2017-11-27

    We have previously developed a new class of inhibitors and chemical probes for glycosyltransferases through base-modification of the sugar-nucleotide donor. The key feature of these donor analogues is the presence of an additional substituent at the nucleobase. To date, the application of this general concept has been limited to UDP-sugars and UDP-sugar-dependent glycosyltransferases. Herein, we report for the first time the application of our approach to a GDP-mannose-dependent mannosyltransferase. We have prepared four GDP-mannose derivatives with an additional substituent at either position 6 or 8 of the nucleobase. These donor analogues were recognised as donor substrates by the mannosyltransferase Kre2p from yeast, albeit with significantly lower turnover rates than the natural donor GDP-mannose. The presence of the additional substituent also redirected enzyme activity from glycosyl transfer to donor hydrolysis. Taken together, our results suggest that modification of the donor nucleobase is, in principle, a viable strategy for probe and inhibitor development against GDP-mannose-dependent GTs. Copyright © 2017 Elsevier Ltd. All rights reserved.

  5. Metabolic Engineering of Yeast and Plants for the Production of the Biologically Active Hydroxystilbene, Resveratrol

    Science.gov (United States)

    Jeandet, Philippe; Delaunois, Bertrand; Aziz, Aziz; Donnez, David; Vasserot, Yann; Cordelier, Sylvain; Courot, Eric

    2012-01-01

    Resveratrol, a stilbenic compound deriving from the phenyalanine/polymalonate route, being stilbene synthase the last and key enzyme of this pathway, recently has become the focus of a number of studies in medicine and plant physiology. Increased demand for this molecule for nutraceutical, cosmetic and possibly pharmaceutic uses, makes its production a necessity. In this context, the use of biotechnology through recombinant microorganisms and plants is particularly promising. Interesting results can indeed arise from the potential of genetically modified microorganisms as an alternative mechanism for producing resveratrol. Strategies used to tailoring yeast as they do not possess the genes that encode for the resveratrol pathway, will be described. On the other hand, most interest has centered in recent years, on STS gene transfer experiments from various origins to the genome of numerous plants. This work also presents a comprehensive review on plant molecular engineering with the STS gene, resulting in disease resistance against microorganisms and the enhancement of the antioxidant activities of several fruits in transgenic lines. PMID:22654481

  6. Yeast Estrogen Screen Assay as a Tool for Detecting Estrogenic Activity in Water Bodies

    Directory of Open Access Journals (Sweden)

    Mirjana Bistan

    2012-01-01

    Full Text Available The presence of endocrine-disrupting compounds in wastewater, surface water, groundwater and even drinking water has become a major concern worldwide, since they negatively affect wildlife and humans. Therefore, these substances should be effectively removed from effluents before they are discharged into surface water to prevent pollution of groundwater, which can be a source of drinking water. Furthermore, an efficient control of endocrine-disrupting compounds in wastewater based on biological and analytical techniques is required. In this study, a yeast estrogen screen (YES bioassay has been introduced and optimized with the aim to assess potential estrogenic activity of waters. First, assay duration, concentration of added substrate to the assay medium and wavelength used to measure the absorbance of the substrate were estimated. Several compounds, such as 17-β-estradiol, 17-α-ethinylestradiol, bisphenol A, nonylphenol, genisteine, hydrocortisone, dieldrin, atrazine, methoxychlor, testosterone and progesterone were used to verify its specificity and sensitivity. The optimized YES assay was sensitive and responded specifically to the selected estrogenic and nonestrogenic compounds in aqueous samples. Potential estrogenicity of influent and effluent samples of two wastewater treatment plants was assessed after the samples had been concentrated by solid-phase extraction (SPE procedure using Oasis® HLB cartridges and methanol as eluting solvent. Up to 90 % of relative estrogenic activity was detected in concentrated samples of influents to wastewater treatment plants and estrogenic activity was still present in the concentrated effluent samples. We found that the introduced YES assay is a suitable screening tool for monitoring the potential estrogenicity of effluents that are discharged into surface water.

  7. 21 CFR 184.1983 - Bakers yeast extract.

    Science.gov (United States)

    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) The...

  8. Digestibilidade total e balanço de nitrogênio em cabritos recebendo rações contendo levedura seca = Total digestibility and nitrogen balance in kid goats receiving diets containing dry yeast

    Directory of Open Access Journals (Sweden)

    Claudete Regina Alcalde

    2011-07-01

    Full Text Available O experimento foi conduzido com o objetivo de avaliar a ingestão,digestibilidade da matéria seca e dos nutrientes, o balanço de nitrogênio e estimar os nutrientes digestíveis totais de rações com a inclusão da levedura seca (0, 25, 50, 75 e 100% da MS em substituição ao farelo de soja nas rações para cabritos. Foram utilizados cinco cabritos SRD alojados em gaiolas metabólicas distribuídos em delineamento quadrado latino 5 x 5. As ingestões de matéria seca e de carboidratos totais não foram alteradas com ainclusão de levedura, no entanto, para a ingestão de matéria orgânica, proteína bruta, extrato etéreo e fibra em detergente neutro foi observado efeito quadrático. A digestibilidade do extrato etéreo apresentou efeito linear decrescente, porém, para digestibilidade da matéria seca, matéria orgânica, proteína bruta, carboidratos totais, fibra em detergente neutro e nutrientes digestíveis totais houve efeito quadrático. O balanço de nitrogênio não foi alterado em função da substituição do farelo de soja. A levedura seca pode ser incluída nas rações de cabritos como fonte proteica sem alterar a ingestão de matéria seca e o balanço de nitrogênio, porém, a inclusão acima de 5,9% de levedura seca nas rações reduz a digestibilidade da matéria seca.The assay was carried out to evaluate feed intake, dry matter andnutrient digestibility, nitrogen balance, and to estimate total digestible nutrients of diets with inclusion of dry yeast (0, 25, 50, 75, 100% of DM replacing soybean meal in diets for kid goats. Five goats were allotted in a 5 x 5 Latin square design and housed in digestibility cages. Dry matter intake and total carbohydrates were unchanged with inclusion of dry yeast; however, for organic matter, crude protein, ether extract and neutral detergent fiber, intake showed a quadratic effect. The digestibility of ether extract showed decreasing linear effect; however, for dry matter, organic matter

  9. Molecular cloning of amphioxus uncoupling protein and assessment of its uncoupling activity using a yeast heterologous expression system

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Kun [Jiangsu Diabetes Research Center, State Key Laboratory of Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, Nanjing, Jiangsu (China); Sun, Guoxun [Department of Hematology, Fourth Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang 150001 (China); Lv, Zhiyuan; Wang, Chen [Jiangsu Diabetes Research Center, State Key Laboratory of Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, Nanjing, Jiangsu (China); Jiang, Xueyuan, E-mail: xueyuanjiang@yahoo.com.cn [Jiangsu Diabetes Research Center, State Key Laboratory of Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, Nanjing, Jiangsu (China); Li, Donghai, E-mail: lidonghai@gmail.com [Jiangsu Diabetes Research Center, State Key Laboratory of Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, Nanjing, Jiangsu (China); Zhang, Chenyu, E-mail: cyzhang@nju.edu.cn [Jiangsu Diabetes Research Center, State Key Laboratory of Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, Nanjing, Jiangsu (China)

    2010-10-01

    Research highlights: {yields} Invertebrates, for example amphioxus, do express uncoupling proteins. {yields} Both the sequence and the uncoupling activity of amphioxus UCP resemble UCP2. {yields} UCP1 is the only UCP that can form dimer on yeast mitochondria. -- Abstract: The present study describes the molecular cloning of a novel cDNA fragment from amphioxus (Branchiostoma belcheri) encoding a 343-amino acid protein that is highly homologous to human uncoupling proteins (UCP), this protein is therefore named amphioxus UCP. This amphioxus UCP shares more homology with and is phylogenetically more related to mammalian UCP2 as compared with UCP1. To further assess the functional similarity of amphioxus UCP to mammalian UCP1 and -2, the amphioxus UCP, rat UCP1, and human UCP2 were separately expressed in Saccharomyces cerevisiae, and the recombinant yeast mitochondria were isolated and assayed for the state 4 respiration rate and proton leak, using pYES2 empty vector as the control. UCP1 increased the state 4 respiration rate by 2.8-fold, and the uncoupling activity was strongly inhibited by GDP, while UCP2 and amphioxus UCP only increased the state 4 respiration rate by 1.5-fold and 1.7-fold in a GDP-insensitive manner, moreover, the proton leak kinetics of amphioxus UCP was very similar to UCP2, but much different from UCP1. In conclusion, the amphioxus UCP has a mild, unregulated uncoupling activity in the yeast system, which resembles mammalian UCP2, but not UCP1.

  10. Molecular cloning of amphioxus uncoupling protein and assessment of its uncoupling activity using a yeast heterologous expression system

    International Nuclear Information System (INIS)

    Chen, Kun; Sun, Guoxun; Lv, Zhiyuan; Wang, Chen; Jiang, Xueyuan; Li, Donghai; Zhang, Chenyu

    2010-01-01

    Research highlights: → Invertebrates, for example amphioxus, do express uncoupling proteins. → Both the sequence and the uncoupling activity of amphioxus UCP resemble UCP2. → UCP1 is the only UCP that can form dimer on yeast mitochondria. -- Abstract: The present study describes the molecular cloning of a novel cDNA fragment from amphioxus (Branchiostoma belcheri) encoding a 343-amino acid protein that is highly homologous to human uncoupling proteins (UCP), this protein is therefore named amphioxus UCP. This amphioxus UCP shares more homology with and is phylogenetically more related to mammalian UCP2 as compared with UCP1. To further assess the functional similarity of amphioxus UCP to mammalian UCP1 and -2, the amphioxus UCP, rat UCP1, and human UCP2 were separately expressed in Saccharomyces cerevisiae, and the recombinant yeast mitochondria were isolated and assayed for the state 4 respiration rate and proton leak, using pYES2 empty vector as the control. UCP1 increased the state 4 respiration rate by 2.8-fold, and the uncoupling activity was strongly inhibited by GDP, while UCP2 and amphioxus UCP only increased the state 4 respiration rate by 1.5-fold and 1.7-fold in a GDP-insensitive manner, moreover, the proton leak kinetics of amphioxus UCP was very similar to UCP2, but much different from UCP1. In conclusion, the amphioxus UCP has a mild, unregulated uncoupling activity in the yeast system, which resembles mammalian UCP2, but not UCP1.

  11. Evolution of cyclin-dependent kinases (CDKs) and CDK-activating kinases (CAKs): differential conservation of CAKs in yeast and metazoa.

    Science.gov (United States)

    Liu, J; Kipreos, E T

    2000-07-01

    Cyclin-dependent kinases (CDKs) function as central regulators of both the cell cycle and transcription. CDK activation depends on phosphorylation by a CDK-activating kinase (CAK). Different CAKs have been identified in budding yeast, fission yeast, and metazoans. All known CAKs belong to the extended CDK family. The sole budding yeast CAK, CAK1, and one of the two CAKs in fission yeast, csk1, have diverged considerably from other CDKs. Cell cycle regulatory components have been largely conserved in eukaryotes; however, orthologs of neither CAK1 nor csk1 have been identified in other species to date. To determine the evolutionary relationships of yeast and metazoan CAKs, we performed a phylogenetic analysis of the extended CDK family in budding yeast, fission yeast, humans, the fruit fly Drosophila melanogaster, and the nematode Caenorhabditis elegans. We observed that there were 10 clades for CDK-related genes, of which seven appeared ancestral, containing both yeast and metazoan genes. The four clades that contain CDKs that regulate transcription by phosphorylating the carboxyl-terminal domain (CTD) of RNA Polymerase II generally have only a single orthologous gene in each species of yeast and metazoans. In contrast, the ancestral cell cycle CDK (analogous to budding yeast CDC28) gave rise to a number of genes in metazoans, as did the ancestor of budding yeast PHO85. One ancestral clade is unique in that there are fission yeast and metazoan members, but there is no budding yeast ortholog, suggesting that it was lost subsequent to evolutionary divergence. Interestingly, CAK1 and csk1 branch together with high bootstrap support values. We used both the relative apparent synapomorphy analysis (RASA) method in combination with the S-F method of sampling reduced character sets and gamma-corrected distance methods to confirm that the CAK1/csk1 association was not an artifact of long-branch attraction. This result suggests that CAK1 and csk1 are orthologs and that a

  12. Improved Screening Method for the Selection of Wine Yeasts Based on Their Pigment Adsorption Activity

    Directory of Open Access Journals (Sweden)

    Andrea Caridi

    2013-01-01

    Full Text Available The aim of this research is to improve an existing low-cost and simple but consistent culturing technique for measuring the adsorption of grape skin pigments on yeasts, comprising: (i growing yeasts in Petri dishes on chromogenic grape-skin-based medium, (ii photographing the yeast biomass, (iii measuring its red, green, and blue colour components, and (iv performing the statistical analysis of the data. Twenty strains of Saccharomyces cerevisiae were grown on different lots of the chromogenic medium, prepared using grape skins from dark cultivars Greco Nero, Magliocco and Nero d’Avola. Microscale wine fermentation trials were also performed. Wide and significant differences among wine yeasts were observed. The chromogenic grape-skin-based medium can be prepared using any grape cultivar, thus allowing the specific selection of the most suitable strain of Saccharomyces cerevisiae for each grape must, mainly for red winemaking. The research provides a useful tool to characterize wine yeasts in relation to pigment adsorption, allowing the improvement of wine colour.

  13. Screening of β-Glucosidase and β-Xylosidase Activities in Four Non-Saccharomyces Yeast Isolates.

    Science.gov (United States)

    López, María Consuelo; Mateo, José Juan; Maicas, Sergi

    2015-08-01

    The finding of new isolates of non-Saccharomyces yeasts, showing beneficial enzymes (such as β-glucosidase and β-xylosidase), can contribute to the production of quality wines. In a selection and characterization program, we have studied 114 isolates of non-Saccharomyces yeasts. Four isolates were selected because of their both high β-glucosidase and β-xylosidase activities. The ribosomal D1/D2 regions were sequenced to identify them as Pichia membranifaciens Pm7, Hanseniaspora vineae Hv3, H. uvarum Hu8, and Wickerhamomyces anomalus Wa1. The induction process was optimized to be carried on YNB-medium supplemented with 4% xylan, inoculated with 106 cfu/mL and incubated 48 h at 28 °C without agitation. Most of the strains had a pH optimum of 5.0 to 6.0 for both the β-glucosidase and β-xylosidase activities. The effect of sugars was different for each isolate and activity. Each isolate showed a characteristic set of inhibition, enhancement or null effect for β-glucosidase and β-xylosidase. The volatile compounds liberated from wine incubated with each of the 4 yeasts were also studied, showing an overall terpene increase (1.1 to 1.3-folds) when wines were treated with non-Saccharomyces isolates. In detail, terpineol, 4-vinyl-phenol and 2-methoxy-4-vinylphenol increased after the addition of Hanseniaspora isolates. Wines treated with Hanseniaspora, Wickerhamomyces, or Pichia produced more 2-phenyl ethanol than those inoculated with other yeasts. © 2015 Institute of Food Technologists®

  14. Strength and Drying Shrinkage of Alkali-Activated Slag Paste and Mortar

    Directory of Open Access Journals (Sweden)

    Mao-chieh Chi

    2012-01-01

    Full Text Available The aim of this study is to investigate the strengths and drying shrinkage of alkali-activated slag paste and mortar. Compressive strength, tensile strength, and drying shrinkage of alkali-activated slag paste and mortar were measured with various liquid/slag ratios, sand/slag ratios, curing ages, and curing temperatures. Experimental results show that the higher compressive strength and tensile strength have been observed in the higher curing temperature. At the age of 56 days, AAS mortars show higher compressive strength than Portland cement mortars and AAS mortars with liquid/slag ratio of 0.54 have the highest tensile strength in all AAS mortars. In addition, AAS pastes of the drying shrinkage are higher than AAS mortars. Meanwhile, higher drying shrinkage was observed in AAS mortars than that observed comparable Portland cement mortars.

  15. Synergistic reduction of toluylene blue induced by acetaldehyde and menadione in yeast cell suspension: Application to determination of yeast cell activity

    Directory of Open Access Journals (Sweden)

    Shiro Yamashoji

    2017-03-01

    Full Text Available Membrane permeant acetaldehyde and menadione induced the synergistic reduction of toluylene blue (TB acting as non-membrane permeant redox indicator in yeast cell suspension. NADH and acetaldehyde also induced the synergistic TB reduction in permeabilized yeast cells and phosphate buffer, but menadione had no ability to promote TB reduction. The pre-incubation of acetaldehyde inhibited the above synergistic reduction of TB in intact and permeabilized yeast cell suspension. The pre-incubation of acetaldehyde might promote NADH oxidation by alcohol dehydrogenase, because acetaldehyde decreased the intracellular NAD(PH concentration. The above facts indicate that the synergistic reduction of TB is controlled by the order of addition of menadione and acetaldehyde. The synergistic reduction of TB by menadione and acetaldehyde was proportional to viable yeast cell number from 104 to 2×106 cells/ml, and this assay was applicable to cytotoxicity test. The time required for the above assay was only 2 min.

  16. BH3-only protein Bim inhibits activity of antiapoptotic members of Bcl-2 family when expressed in yeast.

    Science.gov (United States)

    Juhásová, Barbora; Mentel, Marek; Bhatia-Kiššová, Ingrid; Zeman, Igor; Kolarov, Jordan; Forte, Michael; Polčic, Peter

    2011-09-02

    Proteins of the Bcl-2 family regulate programmed cell death in mammals by promoting the release of cytochrome c from mitochondria in response to various proapoptotic stimuli. The mechanism by which BH3-only members of the family activate multidomain proapoptotic proteins Bax and Bak to form a pore in mitochondrial membranes remains under dispute. We report that cell death promoting activity of BH3-only protein Bim can be reconstituted in yeast when both Bax and antiapoptotic protein Bcl-X(L) are present, suggesting that Bim likely activates Bax indirectly by inhibiting antiapoptotic proteins. Copyright © 2011 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.

  17. The different behaviors of three oxidative mediators in probing the redox activities of the yeast Saccharomyces cerevisiae

    International Nuclear Information System (INIS)

    Zhao Jinsheng; Wang Min; Yang Zhenyu; Wang Zhong; Wang Huaisheng; Yang Zhengyu

    2007-01-01

    The different behaviors of three lipophilic mediators including 2-methyl-1,4-naphthalenedione(menadione), 2,6-dichlorophenolindophenol (DCPIP) and N,N,N',N'-tetramethyl-p-phenylenediamine (TMPD) in probing the redox activity of the yeast Saccharomyces cerevisiae were studied by several comparative factor-influencing experiments. Hydrophilic ferricyanide was employed as an extracellular electron acceptor, and constituted dual mediator system with each of three lipophilic mediators. Limiting-current microelectrode voltammetry was used to measure the quantity of ferrocyanide accumulations, giving a direct measure of the redox activity. It was found that under anaerobic condition, menadione interacts with anaerobic respiration pathway, whereas DCPIP and TMPD interact with fermentation pathway in the yeast. Based on the understanding of the interaction between the yeast and each of three mediators, three mediators were respectively employed in evaluating the toxicity of acetic acid on S. cerevisiae and, the results for the first showed that the mediators are complementary to each other when used as electron carriers in biotoxicity assay

  18. The different behaviors of three oxidative mediators in probing the redox activities of the yeast Saccharomyces cerevisiae

    Energy Technology Data Exchange (ETDEWEB)

    Zhao Jinsheng [Department of Chemistry and Chemical Engineering, Liaocheng University, Liaocheng 252059 (China); Wang Min [School of Medicine, Ehime University, Toon 791-0295 (Japan); Yang Zhenyu [Department of Chemistry, Nanchang University, Jiangxi 330047 (China); Wang Zhong [School of Medicine, Ehime University, Toon 791-0295 (Japan); Wang Huaisheng [Department of Chemistry and Chemical Engineering, Liaocheng University, Liaocheng 252059 (China); Yang Zhengyu [Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100101 (China)

    2007-07-30

    The different behaviors of three lipophilic mediators including 2-methyl-1,4-naphthalenedione(menadione), 2,6-dichlorophenolindophenol (DCPIP) and N,N,N',N'-tetramethyl-p-phenylenediamine (TMPD) in probing the redox activity of the yeast Saccharomyces cerevisiae were studied by several comparative factor-influencing experiments. Hydrophilic ferricyanide was employed as an extracellular electron acceptor, and constituted dual mediator system with each of three lipophilic mediators. Limiting-current microelectrode voltammetry was used to measure the quantity of ferrocyanide accumulations, giving a direct measure of the redox activity. It was found that under anaerobic condition, menadione interacts with anaerobic respiration pathway, whereas DCPIP and TMPD interact with fermentation pathway in the yeast. Based on the understanding of the interaction between the yeast and each of three mediators, three mediators were respectively employed in evaluating the toxicity of acetic acid on S. cerevisiae and, the results for the first showed that the mediators are complementary to each other when used as electron carriers in biotoxicity assay.

  19. Role of killer factors in the inhibitory activity of bio-control yeasts against Penicillium expansum and Aspergillus ochraceus

    Directory of Open Access Journals (Sweden)

    Ciro da Silva Portes

    2013-08-01

    Full Text Available This work evaluated the antagonism of killer positive yeast strains (isolated from 11 samples of different frozen fruit pulps against the strains of Penicillium expansum and Aspergillus ochraceus. Of the total 41 killer yeasts tested in YM agar, 19 showed antibiosis against P. expansum and A. ochraceus, with inhibition zone ranging from 10 to 18 mm and 10 to 19 mm, respectively. In the following step, the extracellular activity of Kluyveromyces sp. FP4(13 was tested performing the assay in YM broth. The antifungal activity of Kluyveromyces sp. FP4(13 cell-free culture supernatant (25ºC/96 h was more effective against the conidia germination, showing inhibition rates of 93.33 and 86.44% for P. expansum and A. ochraceus, respectively. The micelial growth inhibition was 28.45 and 21.0%, respectively. The antagonism showed by the selected yeasts could be used as a promising alternative tool to reduce and control the postharvest fungal spoilage of the fruits. However, further studies should be carried out in order to better elucidate the role of innocuous characters in antagonistic microorganisms, as well as the purification and characterization of new killer toxins.

  20. Effects of Low Molecular Weight Yeast β-Glucan on Antioxidant and Immunological Activities in Mice

    Directory of Open Access Journals (Sweden)

    Na Lei

    2015-09-01

    Full Text Available To evaluate the antioxidant and immune effects of low molecular yeast β-glucan on mice, three sulfated glucans from Saccharomyces cerevisiae (sGSCs with different molecular weight (MW and degrees of sulfation (DS were prepared. The structures of the sGSCs were analyzed through high performance liquid chromatography-gel permeation chromatography (HPLC-GPC and Fourier transform infrared spectroscopy (FTIR. sGSC1, sGSC2, and sGSC3 had MW of 12.9, 16.5 and 19.2 kDa, respectively, and DS of 0.16, 0.24 and 0.27, respectively. In vitro and in vivo experiments were conducted to evaluate the antioxidant and immunological activities of the sGSCs. In vitro experiment, the reactive oxygen species (ROS scavenging activities were determined. In vivo experiment, 50 male BALB/c mice were divided into five groups. The sGSC1, sGSC2 and sGSC3 treatment groups received the corresponding sGSCs at 50 mg/kg/day each. The GSC (glucans from Saccharomyces cerevisiae treatment group received 50 mg/kg/day GSC. The normal control group received equal volume of physiological saline solution. All treatments were administered intragastrically for 14 day. Results showed that sGSC1, sGSC2 and sGSC3 can scavenge 1,1-diphenyl-2-picryl-hydrazyl (DPPH, superoxide, and hydroxyl radicals in vitro. The strength of the radical scavenging effects of the sGSCs was in the order of sGSC1 > sGSC2 > sGSC3. Oral administration of sGSC1 significantly improved serum catalase (CAT and glutathione peroxidase (GSH-Px activities and decreased malondialdehyde (MDA level in mice. sGSC1 significantly improved the spleen and thymus indexes and the lymphocyte proliferation, effectively enhanced the percentage of CD4+ T cells, decreased the percentage of CD8+ T cells, and elevated the CD4+/CD8+ ratio. sGSC1 significantly promoted the secretion of IL-2 and IFN-γ. These results indicate that sGSC1 with low MW and DS has better antioxidant and immunological activities than the other sGSCs, and sGSC1 could

  1. Facilitated recruitment of Pdc2p, a yeast transcriptional activator, in response to thiamin starvation.

    Science.gov (United States)

    Nosaka, Kazuto; Esaki, Hiroyoshi; Onozuka, Mari; Konno, Hiroyuki; Hattori, Yasunao; Akaji, Kenichi

    2012-05-01

    In Saccharomyces cerevisiae, genes involved in thiamin pyrophosphate (TPP) synthesis (THI genes) and the pyruvate decarboxylase structural gene PDC5 are transcriptionally induced in response to thiamin starvation. Three positive regulatory factors (Thi2p, Thi3p, and Pdc2p) are involved in the expression of THI genes, whereas only Pdc2p is required for the expression of PDC5. Thi2p and Pdc2p serve as transcriptional activators and each factor can interact with Thi3p. The target consensus DNA sequence of Thi2p has been deduced. When TPP is not bound to Thi3p, the interactions between the regulatory factors are increased and THI gene expression is upregulated. In this study, we demonstrated that Pdc2p interacts with the upstream region of THI genes and PDC5. The association of Pdc2p or Thi2p with THI gene promoters was enhanced by thiamin starvation, suggesting that Pdc2p and Thi2p assist each other in their recruitment to the THI promoters via interaction with Thi3p. It is highly likely that, under thiamin-deprived conditions, a ternary Thi2p/Thi3p/Pdc2p complex is formed and transactivates THI genes in yeast cells. On the other hand, the association of Pdc2p with PDC5 was unaffected by thiamin. We also identified a DNA element in the upstream region of PDC5, which can bind to Pdc2p and is required for the expression of PDC5. © 2012 Federation of European Microbiological Societies. Published by Blackwell Publishing Ltd. All rights reserved.

  2. Spent yeast as natural source of functional food additives

    Science.gov (United States)

    Rakowska, Rita; Sadowska, Anna; Dybkowska, Ewa; Świderski, Franciszek

    Spent yeasts are by-products arising from beer and wine production which over many years have been chiefly used as feed additives for livestock. They contain many valuable and bioactive substances which has thereby generated much interest in their exploitation. Up till now, the main products obtained from beer-brewing yeasts are β-glucans and yeast extracts. Other like foodstuffs include dried brewer’s yeast, where this is dried and the bitterness removed to be fit for human consumption as well as mannan-oligosaccharides hitherto used in the feed industry. β-glucans constitute the building blocks of yeast cell walls and can thus be used in human nutrition as dietary supplements or serving as food additives in functional foods. β-glucans products obtained via post-fermentation of beer also exhibit a high and multi-faceted biological activity where they improve the blood’s lipid profile, enhance immunological status and have both prebiotic and anti-oxidant properties. Yeast extracts are currently being used more and more to enhance flavour in foodstuffs, particularly for meat and its products. Depending on how autolysis is carried out, it is possible to design extracts of various meat flavours characteristic of specific meats. Many different flavour profiles can be created which may be additionally increased in combination with vegetable extracts. Within the food market, yeast extracts can appear in various guises such as liquids, pastes or powders. They all contain significant amounts of glutamic acid, 5’-GMP and 5’-IMP nucleotides together with various amino acids and peptides that act synergistically for enhancing the flavour of foodstuff products. Recent studies have demonstrated additional benefits of yeast extracts as valuable sources of amino acids and peptides which can be used in functional foods and dietary supplements. These products possess GRAS status (Generally Recognised As Safe) which thereby also adds further as to why they should be used

  3. Species-specific activation of Cu/Zn SOD by its CCS copper chaperone in the pathogenic yeast Candida albicans.

    Science.gov (United States)

    Gleason, Julie E; Li, Cissy X; Odeh, Hana M; Culotta, Valeria C

    2014-06-01

    Candida albicans is a pathogenic yeast of important public health relevance. Virulence of C. albicans requires a copper and zinc containing superoxide dismutase (SOD1), but the biology of C. albicans SOD1 is poorly understood. To this end, C. albicans SOD1 activation was examined in baker's yeast (Saccharomyces cerevisiae), a eukaryotic expression system that has proven fruitful for the study of SOD1 enzymes from invertebrates, plants, and mammals. In spite of the 80% similarity between S. cerevisiae and C. albicans SOD1 molecules, C. albicans SOD1 is not active in S. cerevisiae. The SOD1 appears incapable of productive interactions with the copper chaperone for SOD1 (CCS1) of S. cerevisiae. C. albicans SOD1 contains a proline at position 144 predicted to dictate dependence on CCS1. By mutation of this proline, C. albicans SOD1 gained activity in S. cerevisiae, and this activity was independent of CCS1. We identified a putative CCS1 gene in C. albicans and created heterozygous and homozygous gene deletions at this locus. Loss of CCS1 resulted in loss of SOD1 activity, consistent with its role as a copper chaperone. C. albicans CCS1 also restored activity to C. albicans SOD1 expressed in S. cerevisiae. C. albicans CCS1 is well adapted for activating its partner SOD1 from C. albicans, but not SOD1 from S. cerevisiae. In spite of the high degree of homology between the SOD1 and CCS1 molecules in these two fungal species, there exists a species-specific barrier in CCS-SOD interactions which may reflect the vastly different lifestyles of the pathogenic versus the noninfectious yeast.

  4. Variation of the Phytochemical Constituents and Antioxidant Activities of Zingiber officinale var. rubrum Theilade Associated with Different Drying Methods and Polyphenol Oxidase Activity.

    Science.gov (United States)

    Ghasemzadeh, Ali; Jaafar, Hawa Z E; Rahmat, Asmah

    2016-06-17

    The effects of different drying methods (freeze drying, vacuum oven drying, and shade drying) on the phytochemical constituents associated with the antioxidant activities of Z. officinale var. rubrum Theilade were evaluated to determine the optimal drying process for these rhizomes. Total flavonoid content (TFC), total phenolic content (TPC), and polyphenol oxidase (PPO) activity were measured using the spectrophotometric method. Individual phenolic acids and flavonoids, 6- and 8-gingerol and shogaol were identified by ultra-high performance liquid chromatography method. Ferric reducing antioxidant potential (FRAP) and 1,1-diphenyl-2-picrylhydrazyl (DPPH) assays were used for the evaluation of antioxidant activities. The highest reduction in moisture content was observed after freeze drying (82.97%), followed by vacuum oven drying (80.43%) and shade drying (72.65%). The highest TPC, TFC, and 6- and 8-shogaol contents were observed in samples dried by the vacuum oven drying method compared to other drying methods. The highest content of 6- and 8-gingerol was observed after freeze drying, followed by vacuum oven drying and shade drying methods. Fresh samples had the highest PPO activity and lowest content of flavonoid and phenolic acid compounds compared to dried samples. Rhizomes dried by the vacuum oven drying method represent the highest DPPH (52.9%) and FRAP activities (566.5 μM of Fe (II)/g DM), followed by freeze drying (48.3% and 527.1 μM of Fe (II)/g DM, respectively) and shade drying methods (37.64% and 471.8 μM of Fe (II)/g DM, respectively) with IC50 values of 27.2, 29.1, and 34.8 μg/mL, respectively. Negative and significant correlations were observed between PPO and antioxidant activity of rhizomes. Vacuum oven dried rhizomes can be utilized as an ingredient for the development of value-added food products as they contain high contents of phytochemicals with valuable antioxidant potential.

  5. Humanlike substitutions to Ω-loop D of yeast iso-1-cytochrome c only modestly affect dynamics and peroxidase activity.

    Science.gov (United States)

    Lei, Haotian; Bowler, Bruce E

    2018-06-01

    Structural studies of yeast iso-1-cytochrome c (L.J. McClelland, T.-C. Mou, M.E. Jeakins-Cooley, S.R. Sprang, B.E. Bowler, Proc. Natl. Acad. Sci. U.S.A. 111 (2014) 6648-6653) show that modest movement of Ω-loop D (residues 70-85, average RMSD versus the native structure: 0.81 Å) permits loss of Met80-heme ligation creating an available coordination site to catalyze the peroxidase activity mediated by cytochrome c early in apoptosis. However, Ala81 and Gly83 move significantly (RMSDs of 2.18 and 1.26 Å, respectively). Ala81 and Gly83 evolve to Ile and Val, respectively, in human cytochrome c and peroxidase activity decreases 25-fold relative to the yeast protein at pH 7. To test the hypothesis that these residues evolved to restrict the peroxidase activity of cytochrome c, A81I and G83V variants of yeast iso-1-cytochrome c were prepared. For both variants, the apparent pK a of the alkaline transition increases by 0.2 to 0.3 relative to the wild type (WT) protein and the rate of opening the heme crevice is slowed. The cooperativity of acid unfolding is decreased for the G83V variant. At pH 7 and 8, the catalytic rate constant, k cat , for the peroxidase activity of both variants decreases relative to WT, consistent with the effects on alkaline isomerization. Below pH 7, the loss in the cooperativity of acid unfolding causes k cat for peroxidase activity to increase for the G83V variant relative to WT. Neither variant decreases k cat to the level of the human protein, indicating that other residues also contribute to the low peroxidase activity of human cytochrome c. Copyright © 2018 Elsevier Inc. All rights reserved.

  6. Comparison of different drying methods on the physical properties, bioactive compounds and antioxidant activity of raspberry powders.

    Science.gov (United States)

    Si, Xu; Chen, Qinqin; Bi, Jinfeng; Wu, Xinye; Yi, Jianyong; Zhou, Linyan; Li, Zhaolu

    2016-04-01

    Dehydration has been considered as one of the traditional but most effective techniques for perishable fruits. Raspberry powders obtained after dehydration can be added as ingredients into food formulations such as bakery and dairy products. In this study, raspberry powders obtained by hot air drying (HAD), infrared radiation drying (IRD), hot air and explosion puffing drying (HA-EPD), infrared radiation and microwave vacuum drying (IR-MVD) and freeze drying (FD) were compared on physical properties, bioactive compounds and antioxidant activity. Drying techniques affected the physical properties, bioactive compounds and antioxidant activity of raspberry powders greatly. FD led to significantly higher (P drying methods. However, thermal drying techniques, especially combined drying methods, were superior to FD in final total polyphenol content, total flavonoid content and antioxidant activity. The combined drying methods, especially IR-MVD, showed the highest total polyphenol content (123.22 g GAE kg(-1) dw) and total flavonoid content (0.30 g CAE kg(-1) dw). Additionally, IR-MVD performed better in antioxidant activity retention. Overall, combined drying methods, especially IR-MVD, were found to result in better quality of raspberry powders among the thermal drying techniques. IR-MVD could be recommended for use in the drying industry because of its advantages in time saving and nutrient retention. © 2015 Society of Chemical Industry.

  7. Relationship between metabolism and ovarian activity in dairy cows with different dry period lengths

    NARCIS (Netherlands)

    Chen, J.C.; Soede, N.M.; Dorland, van H.A.; Remmelink, G.J.; Bruckmaier, R.M.; Kemp, B.; Knegsel, van A.T.M.

    2015-01-01

    The objectives of the present study were to evaluate the effects of dry period length on ovarian activity in cows fed a lipogenic or a glucogenic diet within 100 days in milk (DIM) and to determine relationships between ovarian activity and energy balance and metabolic status in early lactation.

  8. Modulation of Spc1 stress-activated protein kinase activity by methylglyoxal through inhibition of protein phosphatase in the fission yeast Schizosaccharomyces pombe

    International Nuclear Information System (INIS)

    Takatsume, Yoshifumi; Izawa, Shingo; Inoue, Yoshiharu

    2007-01-01

    Methylglyoxal, a ubiquitous metabolite derived from glycolysis has diverse physiological functions in yeast cells. Previously, we have reported that extracellularly added methylglyoxal activates Spc1, a stress-activated protein kinase (SAPK), in the fission yeast Schizosaccharomyces pombe [Y. Takatsume, S. Izawa, Y. Inoue, J. Biol. Chem. 281 (2006) 9086-9092]. Phosphorylation of Spc1 by treatment with methylglyoxal in S. pombe cells defective in glyoxalase I, an enzyme crucial for the metabolism of methylglyoxal, continues for a longer period than in wild-type cells. Here we show that methylglyoxal inhibits the activity of the protein phosphatase responsible for the dephosphorylation of Spc1 in vitro. In addition, we found that methylglyoxal inhibits human protein tyrosine phosphatase 1B (PTP1B) also. We propose a model for the regulation of the activity of the Spc1-SAPK signaling pathway by methylglyoxal in S. pombe

  9. The 42-kDa coat protein of Andean potato mottle virus acts as a transcriptional activator in yeast

    Directory of Open Access Journals (Sweden)

    Vidal M.S.

    2002-01-01

    Full Text Available Interactions of viral proteins play an important role in the virus life cycle, especially in capsid assembly. Andean potato mottle comovirus (APMoV is a plant RNA virus with a virion formed by two coat proteins (CP42 and CP22. Both APMoV coat protein open reading frames were cloned into pGBT9 and pGAD10, two-hybrid system vectors. HF7c yeast cells transformed with the p9CP42 construct grew on yeast dropout selection media lacking tryptophan and histidine. Clones also exhibited ß-galactosidase activity in both qualitative and quantitative assays. These results suggest that CP42 protein contains an amino acid motif able to activate transcription of His3 and lacZ reporter genes in Saccharomyces cerevisiae. Several deletions of the CP42 gene were cloned into the pGBT9 vector to locate the region involved in this activation. CP42 constructions lacking 12 residues from the C-terminal region and another one with 267 residues deleted from the N-terminus are still able to activate transcription of reporter genes. However, transcription activation was not observed with construction p9CP42deltaC57, which does not contain the last 57 amino acid residues. These results demonstrate that a transcription activation domain is present at the C-terminus of CP42 between residues 267 and 374.

  10. Antimicrobial activity of broccoli (Brassica oleracea var. italica) cultivar Avenger against pathogenic bacteria, phytopathogenic filamentous fungi and yeast.

    Science.gov (United States)

    Pacheco-Cano, R D; Salcedo-Hernández, R; López-Meza, J E; Bideshi, D K; Barboza-Corona, J E

    2018-01-01

    The objective of this study was to show whether the edible part of broccoli has antibacterial and antifungal activity against micro-organism of importance in human health and vegetable spoilage, and to test if this effect was partially due to antimicrobial peptides (AMPs). Crude extracts were obtained from florets and stems of broccoli cultivar Avenger and the inhibitory effect was demonstrated against pathogenic bacteria (Bacillus cereus, Staphylococcus xylosus, Staphylococcus aureus, Shigella flexneri, Shigella sonnei, Proteus vulgaris), phytopathogenic fungi (Colletotrichum gloeosporioides, Asperigillus niger) and yeasts (Candida albicans and Rhodotorula sp.). It was shown that samples treated with proteolytic enzymes had a reduction of approximately 60% in antibacterial activity against Staph. xylosus, suggesting that proteinaceous compounds might play a role in the inhibitory effect. Antimicrobial components in crude extracts were thermoresistant and the highest activity was observed under acidic conditions. It was shown that antifungal activity of broccoli's crude extracts might not be attributed to chitinases. Organic broccoli cultivar Avenger has antimicrobial activity against pathogenic bacteria, yeast and phytophatogenic fungi. Data suggest that this effect is partially due to AMPs. Broccoli's crude extracts have activity not only against pathogenic bacteria but also against phytophatogenic fungi of importance in agriculture. We suggest for first time that the inhibitory effect is probably due to AMPs. © 2017 The Society for Applied Microbiology.

  11. Immobilisation increases yeast cells' resistance to dehydration-rehydration treatment.

    Science.gov (United States)

    Borovikova, Diana; Rozenfelde, Linda; Pavlovska, Ilona; Rapoport, Alexander

    2014-08-20

    This study was performed with the goal of revealing if the dehydration procedure used in our new immobilisation method noticeably decreases the viability of yeast cells in immobilised preparations. Various yeasts were used in this research: Saccharomyces cerevisiae cells that were rather sensitive to dehydration and had been aerobically grown in an ethanol-containing medium, a recombinant strain of S. cerevisiae grown in aerobic conditions which were completely non-resistant to dehydration and an anaerobically grown bakers' yeast strain S. cerevisiae, as well as a fairly resistant Pichia pastoris strain. Experiments performed showed that immobilisation of all these strains essentially increased their resistance to a dehydration-rehydration treatment. The increase of cells' viability (compared with control cells dehydrated in similar conditions) was from 30 to 60%. It is concluded that a new immobilisation method, which includes a dehydration stage, does not lead to an essential loss of yeast cell viability. Correspondingly, there is no risk of losing the biotechnological activities of immobilised preparations. The possibility of producing dry, active yeast preparations is shown, for those strains that are very sensitive to dehydration and which can be used in biotechnology in an immobilised form. Finally, the immobilisation approach can be used for the development of efficient methods for the storage of recombinant yeast strains. Copyright © 2014 Elsevier B.V. All rights reserved.

  12. The radiation resistance and cobalt biosorption activity of yeast strains isolated from the Lanyu low-level radioactive waste repository in Taiwan.

    Science.gov (United States)

    Li, Chia-Chin; Chung, Hsiao-Ping; Wen, Hsiao-Wei; Chang, Ching-Tu; Wang, Ya-Ting; Chou, Fong-In

    2015-08-01

    The ubiquitous nature of microbes has made them the pioneers in radionuclides adsorption and transport. In this study, the radiation resistance and nuclide biosorption capacity of microbes isolated from the Lanyu low-level radioactive waste (LLRW) repository in Taiwan was assessed, the evaluation of the possibility of using the isolated strain as biosorbents for (60)Co and Co (II) from contaminated aqueous solution and the potential impact on radionuclides release. The microbial content of solidified waste and broken fragments of containers at the Lanyu LLRW repository reached 10(5) CFU/g. Two yeast strains, Candida guilliermondii (CT1) and Rhodotorula calyptogenae (RT1) were isolated. The radiation dose necessary to reduce the microbial count by one log cycle of CT1 and RT1 was 2.1 and 0.8 kGy, respectively. Both CT1 and RT1 can grow under a radiation field with dose rate of 6.8 Gy/h, about 100 times higher than that on the surface of the LLRW container in Lanyu repository. CT1 and RT1 had the maximum (60)Co biosorption efficiency of 99.7 ± 0.1% and 98.3 ± 0.2%, respectively in (60)Co aqueous solution (700 Bq/mL), and the (60)Co could stably retained for more than 30 days in CT 1. Nearly all of the Co was absorbed and reached equilibrium within 1 h by CT1 and RT1 in the 10 μg/g Co (II) aqueous solution. Biosorption efficiency test showed almost all of the Co (II) was adsorbed by CT1 in 20 μg/g Co (II) aqueous solution, the efficiency of biosorption by RT1 in 10 μg/g of Co (II) was lower. The maximum Co (II) sorption capacity of CT1 and RT1 was 5324.0 ± 349.0 μg/g (dry wt) and 3737.6 ± 86.5 μg/g (dry wt), respectively, in the 20 μg/g Co (II) aqueous solution. Experimental results show that microbial activity was high in the Lanyu LLRW repository in Taiwan. Two isolated yeast strains, CT1 and RT1 have high potential for use as biosorbents for (60)Co and Co (II) from contaminated aqueous solution, on the other hand, but may have the

  13. Effect of Freeze-Drying on the Antioxidant Compounds and Antioxidant Activity of Selected Tropical Fruits

    Directory of Open Access Journals (Sweden)

    Muhammad Redzuan Hairuddin

    2011-07-01

    Full Text Available The effects of freeze-drying on antioxidant compounds and antioxidant activity of five tropical fruits, namely starfruit (Averrhoa carambola L., mango (Mangifera indica L., papaya (Carica papaya L., muskmelon (Cucumis melo L., and watermelon Citruluss lanatus (Thunb. were investigated. Significant (p < 0.05 differences, for the amounts of total phenolic compounds (TPC, were found between the fresh and freeze-dried fruit samples, except muskmelon. There was no significant (p > 0.05 change, however, observed in the ascorbic acid content of the fresh and freeze-dried fruits. Similarly, freeze-drying did not exert any considerable effect on β-carotene concentration of fruits, except for mango and watermelon, where significantly (p < 0.05 higher levels were detected in the fresh samples. The results of DPPH (2,2-diphenyl-1-picrylhydrazyl radical scavenging and reducing power assays revealed that fresh samples of starfruit and mango had relatively higher antioxidant activity. In case of linoleic acid peroxidation inhibition measurement, a significant (p < 0.05 but random variation was recorded between the fresh and freeze-dried fruits. Overall, in comparison to β-carotene and ascorbic acid, a good correlation was established between the result of TPC and antioxidant assays, indicating that phenolics might have been the dominant compounds contributing towards the antioxidant activity of the fruits tested.

  14. Yeast: the soul of beer's aroma--a review of flavour-active esters and higher alcohols produced by the brewing yeast.

    Science.gov (United States)

    Pires, Eduardo J; Teixeira, José A; Brányik, Tomás; Vicente, António A

    2014-03-01

    Among the most important factors influencing beer quality is the presence of well-adjusted amounts of higher alcohols and esters. Thus, a heavy body of literature focuses on these substances and on the parameters influencing their production by the brewing yeast. Additionally, the complex metabolic pathways involved in their synthesis require special attention. More than a century of data, mainly in genetic and proteomic fields, has built up enough information to describe in detail each step in the pathway for the synthesis of higher alcohols and their esters, but there is still place for more. Higher alcohols are formed either by anabolism or catabolism (Ehrlich pathway) of amino acids. Esters are formed by enzymatic condensation of organic acids and alcohols. The current paper reviews the up-to-date knowledge in the pathways involving the synthesis of higher alcohols and esters by brewing yeasts. Fermentation parameters affecting yeast response during biosynthesis of these aromatic substances are also fully reviewed.

  15. Radioactivity evaluation method for pre-packed concrete packages of low-level dry active wastes

    International Nuclear Information System (INIS)

    Sakai, Toshiaki; Funahashi, Tetsuo; Watabe, Kiyomi; Ozawa, Yukitoshi; Kashiwagi, Makoto

    1998-01-01

    Low-level dry active wastes of nuclear power plants are grouted with cement mortal in a container and planned to disposed into the shallow land disposal site. The characteristics of radionuclides contained in dry active wastes are same as homogeneous solidified wastes. In the previous report, we reported the applicability of the radioactivity evaluation methods established for homogeneous solidified wastes to pre-packed concrete packages. This report outlines the developed radioactivity evaluation methods for pre-packed concrete packages based upon recent data. Since the characteristics of dry active wastes depend upon the plant system in which dry active wastes originate and the types of contamination, sampling of wastes and activity measurement were executed to derive scaling factors. The radioactivity measurement methods were also verified. The applicability of non-destructive methods to measure radioactivity concentration of pre-packed concrete packages was examined by computer simulation. It is concluded that those methods are accurate enough to measure actual waste packages. (author)

  16. Increased biological activity of deglycosylated recombinant human granulocyte/macrophage colony-stimulating factor produced by yeast or animal cells

    International Nuclear Information System (INIS)

    Moonen, P.; Mermod, J.J.; Ernst, J.F.; Hirschi, M.; DeLamarter, J.F.

    1987-01-01

    Human granulocyte/macrophage colony-stimulating factor (hGM-CSF) produced by several recombinant sources including Escherichia coli, yeast, and animal cells was studied. Recombinant animal cells produced hGM-CSF in low quantities and in multiple forms of varying size. Mammalian hGM-CSF was purified 200,000-fold using immunoaffinity and lectin chromatography. Partially purified proteins produced in yeast and mammalian cells were assayed for the effects of deglycosylation. Following enzymatic deglycosylation, immunoreactivity was measured by radioimmunoassay and biological activity was measured in vitro on responsive human primary cells. Removal of N-linked oligosaccharides from both proteins increased their immunoreactivities by 4- to 8-fold. Removal of these oligosaccharides also increased their specific biological activities about 20-fold, to reach approximately the specific activity of recombinant hGM-CSF from E. coli. The E. coli produced-protein-lacking any carbohydrate- had by far the highest specific activity observed for the recombinant hGM-CSFs

  17. PROPOSAL FOR THE IMPLEMENTATION OF SPRAY DRYING IN THE ACTIVATION PROCESS OF BENTONITE WITH SULFURIC ACID

    OpenAIRE

    Romero, P.; Otiniano, M.

    2014-01-01

    The present work propose the replacement of the three stages of the activation process of bentonite with sulfuric acid by the only stage spray drying. El presente trabajo propone reemplazar tres etapas del proceso de activación de la bentonita con ácido sulfúrico por una sola etapa, la del secado por atomización.

  18. Effect of emulsification and spray-drying microencapsulation on the antilisterial activity of transcinnamaldehyde.

    Science.gov (United States)

    Trinh, Nga-Thi-Thanh; Lejmi, Raja; Gharsallaoui, Adem; Dumas, Emilie; Degraeve, Pascal; Thanh, Mai Le; Oulahal, Nadia

    2015-01-01

    Spray-dried redispersible transcinnamaldehyde (TC)-in-water emulsions were prepared in order to preserve its antibacterial activity; 5% (w/w) TC emulsions were first obtained with a rotor-stator homogeniser in the presence of either soybean lecithin or sodium caseinate as emulsifiers. These emulsions were mixed with a 30% (w/w) maltodextrin solution before feeding a spray-dryer. The antibacterial activity of TC alone, TC emulsions with and without maltodextrin before and after spray-drying were assayed by monitoring the growth at 30 °C of Listeria innocua in their presence and in their absence (control). Whatever the emulsifier used, antilisterial activity of TC was increased following its emulsification. However, reconstituted spray-dried emulsions stabilised by sodium caseinate had a higher antibacterial activity suggesting that they better resisted to spray-drying. This was consistent with observation that microencapsulation efficiencies were 27.6% and 78.7% for emulsions stabilised by lecithin and sodium caseinate, respectively.

  19. SNPs altering ammonium transport activity of human Rhesus factors characterized by a yeast-based functional assay.

    Directory of Open Access Journals (Sweden)

    Aude Deschuyteneer

    Full Text Available Proteins of the conserved Mep-Amt-Rh family, including mammalian Rhesus factors, mediate transmembrane ammonium transport. Ammonium is an important nitrogen source for the biosynthesis of amino acids but is also a metabolic waste product. Its disposal in urine plays a critical role in the regulation of the acid/base homeostasis, especially with an acid diet, a trait of Western countries. Ammonium accumulation above a certain concentration is however pathologic, the cytotoxicity causing fatal cerebral paralysis in acute cases. Alteration in ammonium transport via human Rh proteins could have clinical outcomes. We used a yeast-based expression assay to characterize human Rh variants resulting from non synonymous single nucleotide polymorphisms (nsSNPs with known or unknown clinical phenotypes and assessed their ammonium transport efficiency, protein level, localization and potential trans-dominant impact. The HsRhAG variants (I61R, F65S associated to overhydrated hereditary stomatocytosis (OHSt, a disease affecting erythrocytes, proved affected in intrinsic bidirectional ammonium transport. Moreover, this study reveals that the R202C variant of HsRhCG, the orthologue of mouse MmRhcg required for optimal urinary ammonium excretion and blood pH control, shows an impaired inherent ammonium transport activity. Urinary ammonium excretion was RHcg gene-dose dependent in mouse, highlighting MmRhcg as a limiting factor. HsRhCG(R202C may confer susceptibility to disorders leading to metabolic acidosis for instance. Finally, the analogous R211C mutation in the yeast ScMep2 homologue also impaired intrinsic activity consistent with a conserved functional role of the preserved arginine residue. The yeast expression assay used here constitutes an inexpensive, fast and easy tool to screen nsSNPs reported by high throughput sequencing or individual cases for functional alterations in Rh factors revealing potential causal variants.

  20. Characterization of vanadate-dependent NADH oxidation activity and isolation of yeast DNA which complements a class 1 vanadate resistance mutation

    International Nuclear Information System (INIS)

    Minasi, L.E.

    1989-01-01

    A vanadate-dependent NADH oxidation activity has been characterized in plasma membranes from the yeast S cerevisiae. NADH oxidation activity was maximally stimulated at pH 5.0 in phosphate buffer. NADH oxidation was not dependent on the concentration of plasma membranes. The vanadate-dependent NADH oxidation activity was abolished under anaerobic conditions and the concomitant uptake of oxygen occurred during NADH oxidation. The activity was inhibited by superoxide dismutase and stimulated by the presence of paraquat. These results indicate that the vanadate stimulation of NADH oxidation in yeast plasma membranes occurs as a result of the vanadate-dependent oxidation of NADH by superoxide, generated by a plasma membrane NADH oxidase. 51 V-NMR results indicated that a phosphate-vanadate anhydride was the stimulatory species in pH 5.0 and pH 7.0 phosphate buffer. Yeast DNA has been isolated which complements a class 1 vanadate resistance mutation

  1. Active Elastic Support/Dry Friction Damper with Piezoelectric Ceramic Actuator

    Directory of Open Access Journals (Sweden)

    Liao Mingfu

    2014-01-01

    Full Text Available The basic operation principle of elastic support/dry friction damper in rotor system was introduced and the unbalance response of the rotor with elastic support/dry friction damper was analyzed theoretically. Based on the previous structure using an electromagnet as actuator, an active elastic support/dry friction damper using piezoelectric ceramic actuator was designed and its effectiveness of reducing rotor vibration when rotor traverses its critical speed and blade-out event happened was experimentally verified. The experimental results show that the active elastic support/dry friction damper with piezoelectric ceramic actuator can significantly reduce vibration in rotor system; the vibration amplitude of the rotor in critical speed region decreased more than 2 times, and the active damper can protect the rotor when a blade-out event happened, so the rotor can traverse the critical speed and shut down smoothly. In addition, the structure is much simpler than the previous, the weight was reduced by half and the power consumption was only 5 W.

  2. Effect of Freeze-Drying on the Antioxidant Compounds and Antioxidant Activity of Selected Tropical Fruits

    Science.gov (United States)

    Shofian, Norshahida Mohamad; Hamid, Azizah Abdul; Osman, Azizah; Saari, Nazamid; Anwar, Farooq; Dek, Mohd Sabri Pak; Hairuddin, Muhammad Redzuan

    2011-01-01

    The effects of freeze-drying on antioxidant compounds and antioxidant activity of five tropical fruits, namely starfruit (Averrhoa carambola L.), mango (Mangifera indica L.), papaya (Carica papaya L.), muskmelon (Cucumis melo L.), and watermelon Citruluss lanatus (Thunb.) were investigated. Significant (p 0.05) change, however, observed in the ascorbic acid content of the fresh and freeze-dried fruits. Similarly, freeze-drying did not exert any considerable effect on β-carotene concentration of fruits, except for mango and watermelon, where significantly (p < 0.05) higher levels were detected in the fresh samples. The results of DPPH (2,2-diphenyl-1-picrylhydrazyl) radical scavenging and reducing power assays revealed that fresh samples of starfruit and mango had relatively higher antioxidant activity. In case of linoleic acid peroxidation inhibition measurement, a significant (p < 0.05) but random variation was recorded between the fresh and freeze-dried fruits. Overall, in comparison to β-carotene and ascorbic acid, a good correlation was established between the result of TPC and antioxidant assays, indicating that phenolics might have been the dominant compounds contributing towards the antioxidant activity of the fruits tested. PMID:21845104

  3. Microencapsulation by spray drying of Lannea microcarpa extract: Technological characteristics and antioxidant activity.

    Directory of Open Access Journals (Sweden)

    Francesca Sansone

    2014-08-01

    Full Text Available Context: A functional extract from Lannea microcarpa (Lm, possess interesting antioxidant and anti-inflammatory properties. However, the unprocessed dried extract occurs as sticky and low-water-soluble material showing critical properties for industrial applications. The unprocessed dried extract is not always enough stable to preserve its functional properties, also giving practical difficulties for the manufacturing. Aims: This research aimed to produce Lm extract microparticles with enhanced functional stability and technological characteristics by spray-drying. Methods: Lm extract was microencapsulated by spray-drying using a sodium-carboxymethylcellulose (NaCMC based matrix. Physicochemical and technological characteristics (determined by UV, HPLC, LLS, SEM, DSC, and in vitro dissolution tests, as well as antioxidant properties (DPPH-test of the resulting powder (LmC were examined. Results: The produced spray dried microparticles showed satisfying encapsulation efficiency, good functional stability and enhanced technological properties. The selected carrier and process conditions led to a stable and handling microencapsulated powder form with improved water dissolution rate. Moreover, the matrix was also able to preserve the antioxidant activity of the phenolic compounds-rich extract. Conclusions: The made-up powder resulted in a functional component that can be used with great potential in cosmetics, foods or nutraceutical products.

  4. Control activity of yeast geranylgeranyl diphosphate synthase from dimer interface through H-bonds and hydrophobic interaction.

    Science.gov (United States)

    Chang, Chih-Kang; Teng, Kuo-Hsun; Lin, Sheng-Wei; Chang, Tao-Hsin; Liang, Po-Huang

    2013-04-23

    Previously we showed that yeast geranylgeranyl diphosphate synthase (GGPPS) becomes an inactive monomer when the first N-terminal helix involved in dimerization is deleted. This raises questions regarding why dimerization is required for GGPPS activity and which amino acids in the dimer interface are essential for dimerization-mediated activity. According to the GGPPS crystal structure, three amino acids (N101, N104, and Y105) located in the helix F of one subunit are near the active site of the other subunit. As presented here, when these residues were replaced individually with Ala caused insignificant activity changes, N101A/Y105A and N101A/N104A but not N104A/Y105A showed remarkably decreased k(cat) values (200-250-fold). The triple mutant N101A/N104A/Y105A displayed no detectable activity, although dimer was retained in these mutants. Because N101 and Y105 form H-bonds with H139 and R140 in the other subunit, respectively, we generated H139A/R140A double mutant and found it was inactive and became monomeric. Therefore, the multiple mutations apparently influence the integrity of the catalytic site due to the missing H-bonding network. Moreover, Met111, also on the highly conserved helix F, was necessary for dimer formation and enzyme activity. When Met111 was replaced with Glu, the negative-charged repulsion converted half of the dimer into a monomer. In conclusion, the H-bonds mainly through N101 for maintaining substrate binding stability and the hydrophobic interaction of M111 in dimer interface are essential for activity of yeast GGPPS.

  5. The radiation resistance and cobalt biosorption activity of yeast strains isolated from the Lanyu low-level radioactive waste repository in Taiwan

    International Nuclear Information System (INIS)

    Li, Chia-Chin; Chung, Hsiao-Ping; Wen, Hsiao-Wei; Chang, Ching-Tu; Wang, Ya-Ting; Chou, Fong-In

    2015-01-01

    The ubiquitous nature of microbes has made them the pioneers in radionuclides adsorption and transport. In this study, the radiation resistance and nuclide biosorption capacity of microbes isolated from the Lanyu low-level radioactive waste (LLRW) repository in Taiwan was assessed, the evaluation of the possibility of using the isolated strain as biosorbents for 60 Co and Co (II) from contaminated aqueous solution and the potential impact on radionuclides release. The microbial content of solidified waste and broken fragments of containers at the Lanyu LLRW repository reached 10 5  CFU/g. Two yeast strains, Candida guilliermondii (CT1) and Rhodotorula calyptogenae (RT1) were isolated. The radiation dose necessary to reduce the microbial count by one log cycle of CT1 and RT1 was 2.1 and 0.8 kGy, respectively. Both CT1 and RT1 can grow under a radiation field with dose rate of 6.8 Gy/h, about 100 times higher than that on the surface of the LLRW container in Lanyu repository. CT1 and RT1 had the maximum 60 Co biosorption efficiency of 99.7 ± 0.1% and 98.3 ± 0.2%, respectively in 60 Co aqueous solution (700 Bq/mL), and the 60 Co could stably retained for more than 30 days in CT 1. Nearly all of the Co was absorbed and reached equilibrium within 1 h by CT1 and RT1 in the 10 μg/g Co (II) aqueous solution. Biosorption efficiency test showed almost all of the Co (II) was adsorbed by CT1 in 20 μg/g Co (II) aqueous solution, the efficiency of biosorption by RT1 in 10 μg/g of Co (II) was lower. The maximum Co (II) sorption capacity of CT1 and RT1 was 5324.0 ± 349.0 μg/g (dry wt) and 3737.6 ± 86.5 μg/g (dry wt), respectively, in the 20 μg/g Co (II) aqueous solution. Experimental results show that microbial activity was high in the Lanyu LLRW repository in Taiwan. Two isolated yeast strains, CT1 and RT1 have high potential for use as biosorbents for 60 Co and Co (II) from contaminated aqueous solution, on the other hand, but may have the impact on

  6. Chemical characterization and antioxidant activities comparison in fresh, dried, stir-frying and carbonized ginger.

    Science.gov (United States)

    Li, Yuxin; Hong, Yan; Han, Yanquan; Wang, Yongzhong; Xia, Lunzhu

    2016-02-01

    Ginger (Zingiber officinale Rosc.) is a common dietary adjunct that contributes to the taste and flavor of foods, and is also an important Traditional Chinese medicine (TCM). Different processing methods can produce different processed gingers with dissimilar chemical constituents and pharmacological activities. In this study, an ultra-performance liquid chromatography/quadrupole-time-of-flight mass spectrometry (UPLC/QTOF-MS) was applied to identify the complicated components from fresh, dried, stir-frying and carbonized ginger extracts. All of the 27 compounds were identified from four kinds of ginger samples (fresh, dried, stir-frying and carbonized ginger). Five main constituents (zingerone, 6-gingerol, 8-gingerol, 6-shogaol and 10-gingerol) in these four kinds of ginger sample extracts were simultaneously determined by UPLC-PDA. Meanwhile, the antioxidant effect of fresh, dried, stir-frying and carbonized gingers were evaluated by three assays (2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2'-azinobis(3-ethylbenzthiazolinesulfonic acid) diammonium salt (ABTS), and ferric reducing antioxidant power (FRAP)). The results demonstrated that antioxidant activity of dried ginger was the highest, for its phenolic contents are 5.2-, 1.1- and 2.4-fold higher than that of fresh, stir-frying and carbonized ginger, respectively, the antioxidant activities' results indicated a similar tendency with phenolic contents: dried ginger>stir-frying ginger>fresh ginger>carbonized ginger. The processing contributed to the decreased concentration of gingerols and the increased levels of shogaols, which reducing the antioxidant effects in pace with processing. This study elucidated the relationship of the heating process with the constituents and antioxidant activity, and provided a guide for choosing different kinds of ginger samples on clinical application. Copyright © 2016 Elsevier B.V. All rights reserved.

  7. Analysis of estrogenic activity in environmental waters in Rio de Janeiro state (Brazil) using the yeast estrogen screen.

    Science.gov (United States)

    Dias, Amanda Cristina Vieira; Gomes, Frederico Wegenast; Bila, Daniele Maia; Sant'Anna, Geraldo Lippel; Dezotti, Marcia

    2015-10-01

    The estrogenicity of waters collected from an important hydrological system in Brazil (Paraiba do Sul and Guandu Rivers) was assessed using the yeast estrogen screen (YES) assay. Sampling was performed in rivers and at the outlets of conventional water treatment plants (WTP). The removal of estrogenic activity by ozonation and chlorination after conventional water treatment (clarification and sand filtration) was investigated employing samples of the Guandu River spiked with estrogens and bisphenol A (BPA). The results revealed a preoccupying incidence of estrogenic activity at levels higher than 1ngL(-1) along some points of the rivers. Another matter of concern was the number of samples from WTPs presenting estrogenicity surpassing 1ngL(-1). The oxidation techniques (ozonation and chlorination) were effective for the removal of estrogenic activity and the combination of both techniques led to good results using less amounts of oxidants. Copyright © 2015 Elsevier Inc. All rights reserved.

  8. Antifungal activity of four honeys of different types from Algeria against pathogenic yeast: Candida albicans and Rhodotorula sp.

    Science.gov (United States)

    Moussa, Ahmed; Noureddine, Djebli; Saad, Aissat; Abdelmelek, Meslem; Abdelkader, Benhalima

    2012-07-01

    To evaluate the antifungal activity of four honeys of different types from Algeria against pathogenic yeast i.e. Candida albicans (C. albicans) and Rhodotorula sp. Four Algeria honeys of different botanical origin were analyzed to test antifungal effect against C. albicans, and Rhodotorula sp. Different concentrations (undiluted, 10%, 30%, 50% and 70% w/v) of honey were studied in vitro for their antifugal activity using C. albicans and Rhodotorula sp. as fungal strains. The range of the diameter of zone of inhibition of various concentrations of tested honeys was (7-23 mm) for Rhodotorula sp., while C. albicans showed clearly resistance towards all concentrations used. The MICs of tested honey concentrations against C. albicans and Rhodotorula sp. were (70.09-93.48)% and (4.90-99.70)% v/v, respectively. This study demonstrates that, in vitro, these natural products have clearly an antifungal activity against Rhodotorula sp. and C. albicans.

  9. Influence of drying conditions on the effective diffusivity and activation energy during convective air and vacuum drying of pumpkin

    Directory of Open Access Journals (Sweden)

    Liliana SEREMET (CECLU

    2015-12-01

    Full Text Available The main purpose of the work is to investigate the efficiency of convective air and vacuum processing on pumpkin drying kinetics. The pumpkin samples were of two different geometrical shapes (cylinder and cube and were dried in a laboratory scale hot air dryer using some specific parameters (constant air velocity of 1.0 m/s, three different temperatures 50, 60 and 70ºC suited to relative humidity (RH values of 9.8, 6.5, and 5.4% respectively. The vacuum drying was led at constant pressures of 5 kPa and accordance temperatures of 50, 60 and 70ºC. Moisture transfer from pumpkin slices was described by applying Fick’s diffusion model. Temperature dependence of the effective diffusivity was described by the Arrhenius-type equation. Cylindrical samples have a slightly better behaviour compared to cubic samples, due to the disposition of the tissues, and the mass and thermic transfer possibilities. Analysing the results of both drying methods, it was deduced that the most efficient method is convective air drying at 70ºC.

  10. Nitrile Metabolizing Yeasts

    Science.gov (United States)

    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

  11. Drying effect on flavonoid composition and antioxidant activity of immature kumquat.

    Science.gov (United States)

    Lou, Shyi-Neng; Lai, Yi-Chun; Huang, Jia-De; Ho, Chi-Tang; Ferng, Lin-Huei A; Chang, Yung-Chung

    2015-03-15

    A seven flavonoids in hot water extract of immature kumquat (Citrus japonica var. margarita) were identified and quantified (mg/100g fresh fruit): 3',5'-di-C-β-glucopyranosylphloretin (DGPP, 285.9 ± 2.9 mg/100g), acacetin 8-C-neohesperidoside (margaritene, 136.2 ± 2.6 mg/100g), acacetin 6-C-neohesperidoside (isomargaritene, 119.1 ± 1.8 mg/100g), fortunellin (acacetin 7-O-neohesperidoside, 28.5 ± 0.7 mg/100g), apigenin 8-C-neohesperidoside (16.9 ± 0.1mg/100g), poncirin (isosakuranetin 7-O-neohesperidoside, 5.1 ± 0.1mg/100g), and rhoifolin (apigenin 7-O-neohesperidoside, 2.0 ± 0.1mg/100g). When immature kumquat was dried at 110 and 130°C for 0.5h, the antioxidant activity, total phenolic content and identified flavonoids increased. The UV absorbance of browning products of immature kumquat dried at 130°C for 1.5h increased dramatically, while the identified flavonoids decreased. Therefore, it was concluded that drying below 130°C for 1.0 h, could release phenolic compounds, which resulted in the increasing antioxidant activity. Drying at 130°C for 1.5h, it might be due to the effect of formed browning products. Copyright © 2014 Elsevier Ltd. All rights reserved.

  12. Combinatorial Screening for Transgenic Yeasts with High Cellulase Activities in Combination with a Tunable Expression System.

    Directory of Open Access Journals (Sweden)

    Yoichiro Ito

    Full Text Available Combinatorial screening used together with a broad library of gene expression cassettes is expected to produce a powerful tool for the optimization of the simultaneous expression of multiple enzymes. Recently, we proposed a highly tunable protein expression system that utilized multiple genome-integrated target genes to fine-tune enzyme expression in yeast cells. This tunable system included a library of expression cassettes each composed of three gene-expression control elements that in different combinations produced a wide range of protein expression levels. In this study, four gene expression cassettes with graded protein expression levels were applied to the expression of three cellulases: cellobiohydrolase 1, cellobiohydrolase 2, and endoglucanase 2. After combinatorial screening for transgenic yeasts simultaneously secreting these three cellulases, we obtained strains with higher cellulase expressions than a strain harboring three cellulase-expression constructs within one high-performance gene expression cassette. These results show that our method will be of broad use throughout the field of metabolic engineering.

  13. Combinatorial Screening for Transgenic Yeasts with High Cellulase Activities in Combination with a Tunable Expression System

    Science.gov (United States)

    Ito, Yoichiro; Yamanishi, Mamoru; Ikeuchi, Akinori; Imamura, Chie; Matsuyama, Takashi

    2015-01-01

    Combinatorial screening used together with a broad library of gene expression cassettes is expected to produce a powerful tool for the optimization of the simultaneous expression of multiple enzymes. Recently, we proposed a highly tunable protein expression system that utilized multiple genome-integrated target genes to fine-tune enzyme expression in yeast cells. This tunable system included a library of expression cassettes each composed of three gene-expression control elements that in different combinations produced a wide range of protein expression levels. In this study, four gene expression cassettes with graded protein expression levels were applied to the expression of three cellulases: cellobiohydrolase 1, cellobiohydrolase 2, and endoglucanase 2. After combinatorial screening for transgenic yeasts simultaneously secreting these three cellulases, we obtained strains with higher cellulase expressions than a strain harboring three cellulase-expression constructs within one high-performance gene expression cassette. These results show that our method will be of broad use throughout the field of metabolic engineering. PMID:26692026

  14. Effective moisture diffusivity and activation energy of rambutan seed under different drying methods to promote storage stability

    Science.gov (United States)

    Ahmad, So'bah; Shamsul Anuar, Mohd; Saleena Taip, Farah; Shamsudin, Rosnah; M, Siti Roha A.

    2017-05-01

    The effects of two drying methods, oven and microwave drying on the effective moisture diffusivity and activation energy of rambutan seed were studied. Effective moisture diffusivity and activation energy are the main indicators used for moisture movement within the material. Hence, it is beneficial to determine an appropriate drying method to attain a final moisture content of rambutan seed that potentially could be used as secondary sources in the industry. An appropriate final moisture content will provide better storage stability that can extend the lifespan of the rambutan seed. The rambutan seeds were dried with two drying methods (oven and microwave) at two level of the process variables (oven temperature; 40°C and 60°C and microwave power; 250W and 1000W) at constant initial moisture contents. The result showed that a higher value of effective moisture diffusivity and less activation energy were observed in microwave drying compared to oven drying. This finding portrays microwave drying expedites the moisture removal to achieve the required final moisture content and the most appropriate drying method for longer storage stability for rambutan seed. With respect to the process variables; higher oven temperatures and lower microwave powers also exhibit similar trends. Hopefully, this study would provide a baseline data to determine an appropriate drying method for longer storage period for turning waste to by-products.

  15. Fission yeast APC/C activators Slp1 and Fzr1 sequentially trigger two consecutive nuclear divisions during meiosis.

    Science.gov (United States)

    Chikashige, Yuji; Yamane, Miho; Okamasa, Kasumi; Osakada, Hiroko; Tsutsumi, Chihiro; Nagahama, Yuki; Fukuta, Noriko; Haraguchi, Tokuko; Hiraoka, Yasushi

    2017-04-01

    In meiosis, two rounds of nuclear division occur consecutively without DNA replication between the divisions. We isolated a fission yeast mutant in which the nucleus divides only once to generate two spores, as opposed to four, in meiosis. In this mutant, we found that the initiation codon of the slp1 + gene is converted to ATA, producing a reduced amount of Slp1. As a member of the Fizzy family of anaphase-promoting complex/cyclosome (APC/C) activators, Slp1 is essential for vegetative growth; however, the mutant allele shows a phenotype only in meiosis. Slp1 insufficiency delays degradation of maturation-promoting factor at the first meiotic division, and another APC/C activator, Fzr1, which acts late in meiosis, terminates meiosis immediately after the delayed first division to produce two viable spores. © 2017 Federation of European Biochemical Societies.

  16. Mutation of yeast Eug1p CXXS active sites to CXXC results in a dramatic increase in protein disulphide isomerase activity

    DEFF Research Database (Denmark)

    Nørgaard, P; Winther, Jakob R.

    2001-01-01

    to thioredoxin and with CXXC catalytic motifs. EUG1 encodes a yeast protein, Eug1p, that is highly homologous to PDI. However, Eug1p contains CXXS motifs instead of CXXC. In the current model for PDI function both cysteines in this motif are required for PDI-catalysed oxidase activity. To gain more insight...... into the biochemical properties of this unusual variant of PDI we have purified and characterized the protein. We have furthermore generated a number of mutant forms of Eug1p in which either or both of the active sites have been mutated to a CXXC sequence. To determine the catalytic capacity of the wild...

  17. Phosphatase activity and culture conditions of the yeast Candida mycoderma sp. and analysis of organic phosphorus hydrolysis ability.

    Science.gov (United States)

    Yan, Mang; Yu, Liufang; Zhang, Liang; Guo, Yuexia; Dai, Kewei; Chen, Yuru

    2014-11-01

    Orthophosphate is an essential but limiting macronutrient for plant growth. About 67% cropland in China lacks sufficient phosphorus, especially that with red soil. Extensive soil phosphorus reserves exist in the form of organic phosphorus, which is unavailable for root uptake unless hydrolyzed by secretory acid phosphatases. Thus, many microorganisms with the ability to produce phosphatase have been exploited. In this work, the activity of an extracellular acid phosphatase and yeast biomass from Candida mycoderma was measured under different culture conditions, such as pH, temperature, and carbon source. A maximal phosphatase activity of 8.47×10(5)±0.11×10(5)U/g was achieved by C. Mycoderma in 36 hr under the optimal conditions. The extracellular acid phosphatase has high activity over a wide pH tolerance range from 2.5 to 5.0 (optimum pH3.5). The effects of different phosphorus compounds on the acid phosphatase production were also studied. The presence of phytin, lecithin or calcium phosphate reduced the phosphatase activity and biomass yield significantly. In addition, the pH of the culture medium was reduced significantly by lecithin. The efficiency of the strain in releasing orthophosphate from organic phosphorus was studied in red soil (used in planting trees) and rice soil (originating as red soil). The available phosphorus content was increased by 230% after inoculating 20 days in rice soil and decreased by 50% after inoculating 10 days in red soil. This work indicates that the yeast strain C. mycoderma has potential application for enhancing phosphorus utilization in plants that grow in rice soil. Copyright © 2014. Published by Elsevier B.V.

  18. Resource Limitations on Soil Microbial Activity in an Antarctic Dry Valley

    DEFF Research Database (Denmark)

    Sparrow, Asley; Gregorich, Ed; Hopkins, David

    2011-01-01

    Although Antarctic dry valley soils function under some of the harshest environmental conditions on the planet, there is significant biological activity concentrated in small areas in the landscape. These productive areas serve as a source of C and N in organic matter redistributed...... to the surrounding biologically impoverished soils. We conducted a 3-yr replicated field experiment involving soil amendment with C and N in simple (glucose and NH4Cl) and complex (glycine and lacustrine detritus) forms to evaluate the resource limitations on soil microbial activity in an Antarctic dry valley....... The respiratory response for all substrates was slow, with a significant but weak response to NH4Cl, followed by a more widespread response to all substrates after 2 yr and in laboratory incubations conducted 3 yr after substrate addition. This response suggests that the soil microbial community is N limited and...

  19. Radiation stimulation of yeast crops for increasing output of alcohol and baker yeasts

    International Nuclear Information System (INIS)

    Vlad, E.; Marsheu, P.

    1974-01-01

    The purpose of this study was to stimulate by gamma radiation the existing commercial types of yeast so as to obtain yeasts that would better reflect the substrate and have improved reproductive capacity. The experiments were conducted under ordinary conditions using commercial yeasts received from one factory producing alcohol and bakery yeasts and isolated as pure cultures. Irradiating yeast cultures with small doses (up to 10 krad) was found to stimulate the reproduction and fermenting activity of yeast cells as manifested in increased accumulation of yeast biomass and greater yield of ethyl alcohol. (E.T.)

  20. Instrumental neutron activation analysis of dry atmospheric fall-out and rain-water

    International Nuclear Information System (INIS)

    Schutyser, P.; Maenhaut, W.; Dams, R.

    1978-01-01

    An automated precipitation sampler and an instrumental neutron activation analysis (i.n.a.a.) method for the determination of some major and trace elements in dry atmospheric fall-out and rain-water are presented. The sampler features a rain detector which makes separate collections of dry atmospheric fall-out and rain-water possible. The sampler is equipped with u.v. lamps in order to avoid algal growth during extended collection periods. After collection, the samples are separated into water-soluble and insoluble fractions. The soluble fraction is preconcentrated before analysis by freeze-drying. The i.n.a.a. method involves the measurement of both short- and long-lived radioactivities so that a total of 35 elements can be determined. The possibility of losses during freeze-drying and the accuracy of the i.n.a.a. method were investigated for 7 elements by analysis of a soluble fraction with an independent method, viz. inductively coupled plasma atomic emission spectrometry. (Auth.)

  1. Alcohol dehydrogenase gene ADH3 activates glucose alcoholic fermentation in genetically engineered Dekkera bruxellensis yeast

    DEFF Research Database (Denmark)

    Schifferdecker, Anna Judith; Siurkus, Juozas; Andersen, Mikael Rørdam

    2016-01-01

    Dekkera bruxellensis is a non-conventional Crabtree-positive yeast with a good ethanol production capability. Compared to Saccharomyces cerevisiae, its tolerance to acidic pH and its utilization of alternative carbon sources make it a promising organism for producing biofuel. In this study, we...... developed an auxotrophic transformation system and an expression vector, which enabled the manipulation of D. bruxellensis, thereby improving its fermentative performance. Its gene ADH3, coding for alcohol dehydrogenase, was cloned and overexpressed under the control of the strong and constitutive promoter...... TEF1. Our recombinant D. bruxellensis strain displayed 1.4 and 1.7 times faster specific glucose consumption rate during aerobic and anaerobic glucose fermentations, respectively; it yielded 1.2 times and 1.5 times more ethanol than did the parental strain under aerobic and anaerobic conditions...

  2. Peptide (Lys-Leu) and amino acids (Lys and Leu) supplementations improve physiological activity and fermentation performance of brewer's yeast during very high-gravity (VHG) wort fermentation.

    Science.gov (United States)

    Yang, Huirong; Zong, Xuyan; Cui, Chun; Mu, Lixia; Zhao, Haifeng

    2017-12-22

    Lys and Leu were generally considered as the key amino acids for brewer's yeast during beer brewing. In the present study, peptide Lys-Leu and a free amino acid (FAA) mixture of Lys and Leu (Lys + Leu) were supplemented in 24 °P wort to examine their effects on physiological activity and fermentation performance of brewer's yeast during very high-gravity (VHG) wort fermentation. Results showed that although both peptide Lys-Leu and their FAA mixture supplementations could increase the growth and viability, intracellular trehalose and glycerol content, wort fermentability, and ethanol content for brewer's yeast during VHG wort fermentation, and peptide was better than their FAA mixture at promoting growth and fermentation for brewer's yeast when the same dose was kept. Moreover, peptide Lys-Leu supplementation significantly increased the assimilation of Asp, but decreased the assimilation of Gly, Ala, Val, (Cys)2, Ile, Leu, Tyr, Phe, Lys, Arg, and Pro. However, the FAA mixture supplementation only promoted the assimilation of Lys and Leu, while reduced the absorption of total amino acids to a greater extent. Thus, the peptide Lys-Leu was more effective than their FAA mixture on the improvement of physiological activity, fermentation performance, and nitrogen metabolism of brewer's yeast during VHG wort fermentation. © 2017 International Union of Biochemistry and Molecular Biology, Inc.

  3. Supercompactor force effectiveness as related to dry active waste volume reduction

    International Nuclear Information System (INIS)

    Williams, P.C.; Phillips, W.S.

    1986-01-01

    The first U.S. permanently installed supercompactor is now in operation at the Babcock and Wilcox volume reduction center, Parks Township, Pennsylvania. Tests with various DAW (dry active waste) material have been conducted, recording press force versus drum height as one means of estimating volume reduction capability of this machine at various compaction forces. The results of these tests, as well as other factors, are presented herein

  4. Pectin Methyl Esterase Activity Change in Intermediate Moisture Sun-Dried Figs after Storage

    Directory of Open Access Journals (Sweden)

    Dilek Demirbüker Kavak

    2015-12-01

    Full Text Available Intermediate moisture fruits can be obtained by rehydrating dried fruits. Intermediate moisture fruits are suitable for direct consumption compared to dry fruits and can be directly used in the production of various products such as bakery products, dairy products and candies. Aim of this study is to compare the pectin methyl esterase (PME activity of intermediate moisture figs which causes softening of the texture and to compare their microbial stability after 3 months storage period. For this purpose, dried figs were rehydrated in 30 and 80° C water until they reach 30% moisture content. Rehydrated samples were stored for 3 months at +4°C. Results showed that there was no statistically significant difference between the control samples and the samples rehydrated at 80°C according to the total viable counts. At the end of the storage period, results of residual PME activity in control samples was 24.1 μmol COOH min-1g-1, while it was found 17.4 μmol COOH min-1g-1 in samples rehydrated at 80°C. As a result rehydration conducted at 80°C provided 28% reduction in PME activity compared to the control samples rehydrated at 30°C, although it did not affect the microbial load significantly after storage.

  5. Mediator, TATA-binding Protein, and RNA Polymerase II Contribute to Low Histone Occupancy at Active Gene Promoters in Yeast*

    Science.gov (United States)

    Ansari, Suraiya A.; Paul, Emily; Sommer, Sebastian; Lieleg, Corinna; He, Qiye; Daly, Alexandre Z.; Rode, Kara A.; Barber, Wesley T.; Ellis, Laura C.; LaPorta, Erika; Orzechowski, Amanda M.; Taylor, Emily; Reeb, Tanner; Wong, Jason; Korber, Philipp; Morse, Randall H.

    2014-01-01

    Transcription by RNA polymerase II (Pol II) in eukaryotes requires the Mediator complex, and often involves chromatin remodeling and histone eviction at active promoters. Here we address the role of Mediator in recruitment of the Swi/Snf chromatin remodeling complex and its role, along with components of the preinitiation complex (PIC), in histone eviction at inducible and constitutively active promoters in the budding yeast Saccharomyces cerevisiae. We show that recruitment of the Swi/Snf chromatin remodeling complex to the induced CHA1 promoter, as well as its association with several constitutively active promoters, depends on the Mediator complex but is independent of Mediator at the induced MET2 and MET6 genes. Although transcriptional activation and histone eviction at CHA1 depends on Swi/Snf, Swi/Snf recruitment is not sufficient for histone eviction at the induced CHA1 promoter. Loss of Swi/Snf activity does not affect histone occupancy of several constitutively active promoters; in contrast, higher histone occupancy is seen at these promoters in Mediator and PIC component mutants. We propose that an initial activator-dependent, nucleosome remodeling step allows PIC components to outcompete histones for occupancy of promoter sequences. We also observe reduced promoter association of Mediator and TATA-binding protein in a Pol II (rpb1-1) mutant, indicating mutually cooperative binding of these components of the transcription machinery and indicating that it is the PIC as a whole whose binding results in stable histone eviction. PMID:24727477

  6. Select polyphenolic fractions from dried plum enhance osteoblast activity through BMP-2 signaling.

    Science.gov (United States)

    Graef, Jennifer L; Rendina-Ruedy, Elizabeth; Crockett, Erica K; Ouyang, Ping; King, Jarrod B; Cichewicz, Robert H; Lucas, Edralin A; Smith, Brenda J

    2018-05-01

    Dried plum supplementation has been shown to enhance bone formation while suppressing bone resorption. Evidence from previous studies has demonstrated that these responses can be attributed in part to the fruit's polyphenolic compounds. The purpose of this study was to identify the most bioactive polyphenolic fractions of dried plum with a focus on their osteogenic activity and to investigate their mechanisms of action under normal and inflammatory conditions. Utilizing chromatographic techniques, six fractions of polyphenolic compounds were prepared from a crude extract of dried plum. Initial screening assays revealed that two fractions (DP-FrA and DP-FrB) had the greatest osteogenic potential. Subsequent experiments using primary bone-marrow-derived osteoblast cultures demonstrated these two fractions enhanced extracellular alkaline phosphatase (ALP), an indicator of osteoblast activity, and mineralized nodule formation under normal conditions. Both fractions enhanced bone morphogenetic protein (BMP) signaling, as indicated by increased Bmp2 and Runx2 gene expression and protein levels of phosphorylated Smad1/5. DP-FrB was most effective at up-regulating Tak1 and Smad1, as well as protein levels of phospho-p38. Under inflammatory conditions, TNF-α suppressed ALP and tended to decrease nodule formation (P=.0674). This response coincided with suppressed gene expression of Bmp2 and the up-regulation of Smad6, an inhibitor of BMP signaling. DP-FrA and DP-FrB partially normalized these responses. Our results show that certain fractions of polyphenolic compounds in dried plum up-regulate osteoblast activity by enhancing BMP signaling, and when this pathway is inhibited by TNF-α, the osteogenic response is attenuated. Copyright © 2017 Elsevier Inc. All rights reserved.

  7. Deteriorated stress response in stationary-phase yeast: Sir2 and Yap1 are essential for Hsf1 activation by heat shock and oxidative stress, respectively.

    Directory of Open Access Journals (Sweden)

    Inbal Nussbaum

    Full Text Available Stationary-phase cultures have been used as an important model of aging, a complex process involving multiple pathways and signaling networks. However, the molecular processes underlying stress response of non-dividing cells are poorly understood, although deteriorated stress response is one of the hallmarks of aging. The budding yeast Saccharomyces cerevisiae is a valuable model organism to study the genetics of aging, because yeast ages within days and are amenable to genetic manipulations. As a unicellular organism, yeast has evolved robust systems to respond to environmental challenges. This response is orchestrated largely by the conserved transcription factor Hsf1, which in S. cerevisiae regulates expression of multiple genes in response to diverse stresses. Here we demonstrate that Hsf1 response to heat shock and oxidative stress deteriorates during yeast transition from exponential growth to stationary-phase, whereas Hsf1 activation by glucose starvation is maintained. Overexpressing Hsf1 does not significantly improve heat shock response, indicating that Hsf1 dwindling is not the major cause for Hsf1 attenuated response in stationary-phase yeast. Rather, factors that participate in Hsf1 activation appear to be compromised. We uncover two factors, Yap1 and Sir2, which discretely function in Hsf1 activation by oxidative stress and heat shock. In Δyap1 mutant, Hsf1 does not respond to oxidative stress, while in Δsir2 mutant, Hsf1 does not respond to heat shock. Moreover, excess Sir2 mimics the heat shock response. This role of the NAD+-dependent Sir2 is supported by our finding that supplementing NAD+ precursors improves Hsf1 heat shock response in stationary-phase yeast, especially when combined with expression of excess Sir2. Finally, the combination of excess Hsf1, excess Sir2 and NAD+ precursors rejuvenates the heat shock response.

  8. Deteriorated stress response in stationary-phase yeast: Sir2 and Yap1 are essential for Hsf1 activation by heat shock and oxidative stress, respectively.

    Science.gov (United States)

    Nussbaum, Inbal; Weindling, Esther; Jubran, Ritta; Cohen, Aviv; Bar-Nun, Shoshana

    2014-01-01

    Stationary-phase cultures have been used as an important model of aging, a complex process involving multiple pathways and signaling networks. However, the molecular processes underlying stress response of non-dividing cells are poorly understood, although deteriorated stress response is one of the hallmarks of aging. The budding yeast Saccharomyces cerevisiae is a valuable model organism to study the genetics of aging, because yeast ages within days and are amenable to genetic manipulations. As a unicellular organism, yeast has evolved robust systems to respond to environmental challenges. This response is orchestrated largely by the conserved transcription factor Hsf1, which in S. cerevisiae regulates expression of multiple genes in response to diverse stresses. Here we demonstrate that Hsf1 response to heat shock and oxidative stress deteriorates during yeast transition from exponential growth to stationary-phase, whereas Hsf1 activation by glucose starvation is maintained. Overexpressing Hsf1 does not significantly improve heat shock response, indicating that Hsf1 dwindling is not the major cause for Hsf1 attenuated response in stationary-phase yeast. Rather, factors that participate in Hsf1 activation appear to be compromised. We uncover two factors, Yap1 and Sir2, which discretely function in Hsf1 activation by oxidative stress and heat shock. In Δyap1 mutant, Hsf1 does not respond to oxidative stress, while in Δsir2 mutant, Hsf1 does not respond to heat shock. Moreover, excess Sir2 mimics the heat shock response. This role of the NAD+-dependent Sir2 is supported by our finding that supplementing NAD+ precursors improves Hsf1 heat shock response in stationary-phase yeast, especially when combined with expression of excess Sir2. Finally, the combination of excess Hsf1, excess Sir2 and NAD+ precursors rejuvenates the heat shock response.

  9. Validating the Heat Stress Indices for Using In Heavy Work Activities in Hot and Dry Climates.

    Science.gov (United States)

    Hajizadeh, Roohalah; Golbabaei, Farideh; Farhang Dehghan, Somayeh; Beheshti, Mohammad Hossein; Jafari, Sayed Mohammad; Taheri, Fereshteh

    2016-01-01

    Necessity of evaluating heat stress in the workplace, require validation of indices and selection optimal index. The present study aimed to assess the precision and validity of some heat stress indices and select the optimum index for using in heavy work activities in hot and dry climates. It carried out on 184 workers from 40 brick kilns workshops in the city of Qom, central Iran (as representative hot and dry climates). After reviewing the working process and evaluation the activity of workers and the type of work, environmental and physiological parameters according to standards recommended by International Organization for Standardization (ISO) including ISO 7243 and ISO 9886 were measured and indices were calculated. Workers engaged in indoor kiln experienced the highest values of natural wet temperature, dry temperature, globe temperature and relative humidity among studied sections (Pstress index (HSI) indices had the highest correlation with other physiological parameters among the other heat stress indices. Relationship between WBGT index and carotid artery temperature (r=0.49), skin temperature (r=0.319), and oral temperature (r=0.203) was statistically significant (P=0.006). Since WBGT index, as the most applicable index for evaluating heat stress in workplaces is approved by ISO, and due to the positive features of WBGT such as ease of measurement and calculation, and with respect to some limitation in application of HSI; WBGT can be introduced as the most valid empirical index of heat stress in the brick workshops.

  10. Physicochemical and Antioxidant Activities of Spray-dried Pitaya Fruit Powder

    Science.gov (United States)

    Li, Guopeng; Liu, Yangyang; Lin, Lijing; Li, Jihua

    2018-01-01

    Pitaya commonly known as dragon fruit is very popular in China due to its intense color, constituent minerals, vitamins, and antioxidant properties. In the present study, physiochemical properties and antioxidant activities of fruit powder from two pitaya cultivars (namely red flesh and white flesh) and fruit peel were observed. Compared with the fruit powder of fruit flesh, the fruit powder made from fruit peel showed a higher antioxidant activity. The current study provides insights to produce spray-dried pitaya fruit powders that could potentially be used as functional food ingredients in various food fields.

  11. Conversion of defective molasses into alcohol and yeasts

    Energy Technology Data Exchange (ETDEWEB)

    Luchev, S.

    1966-01-01

    The addition of small quantities (0.05 to 0.75%) of dried malt roots, green malt roots, green malt, yeast hydrolyzate, corn extraction, and tomato juice improved the quality and accelerated the brewing process in defective molasses. Dried malt roots and yeast hydrolyzate were the least expensive preparations.

  12. Bioactive phytochemicals and antioxidant activity in fresh and dried lychee fractions1

    Directory of Open Access Journals (Sweden)

    Estela de Rezende Queiroz

    Full Text Available Fruit of the lychee cv. Bengal are approximately 50% peel and seeds, which are discarded. These by-products have antioxidant compounds which are capable of blocking the harmful effects of free radicals in the body. Bioactive compounds (ascorbic acid, beta-carotene, lycopene and phenols and antioxidant activity were evaluated in different extracts, both fresh and dried at 45 °C, of the skin, pulp and seeds of the lychee, which were subjected to principal component analysis to clarify which of the compounds are responsible for this activity. Principal component analysis explained 82.90% of the variance of the antioxidant profile of the lychee. The peel displayed higher levels of phenols, ascorbic acid, beta-carotene and antioxidant activity, while the seeds stood out due to their levels of lycopene. With drying, there was a decrease in the levels of ascorbic acid and beta-carotene and in antioxidant activity, with an increase in the levels of phenols and lycopene. The antioxidant activity found in the peel and seeds of the lychee is high, and is mainly due to ascorbic acid and beta-carotene, as demonstrated by principal component analysis, allowing the use of these fractions as sources of natural antioxidants.

  13. Msn2p/Msn4p act as a key transcriptional activator of yeast cytoplasmic thiol peroxidase II.

    Science.gov (United States)

    Hong, Seung-Keun; Cha, Mee-Kyung; Choi, Yong-Soo; Kim, Won-Cheol; Kim, Il-Han

    2002-04-05

    We observed that the transcription of Saccharomyces cerevisiae cytoplasmic thiol peroxidase type II (cTPx II) (YDR453C) is regulated in response to various stresses (e.g. oxidative stress, carbon starvation, and heat-shock). It has been suggested that both transcription-activating proteins, Yap1p and Skn7p, regulate the transcription of cTPx II upon exposure to oxidative stress. However, a dramatic loss of transcriptional response to various stresses in yeast mutant strains lacking both Msn2p and Msn4p suggests that the transcription factors act as a principal transcriptional activator. In addition to two Yap1p response elements (YREs), TTACTAA and TTAGTAA, the presence of two stress response elements (STREs) (CCCCT) in the upstream sequence of cTPx II also suggests that Msn2p/Msn4p could control stress-induced expression of cTPx II. Analysis of the transcriptional activity of site-directed mutagenesis of the putative STREs (STRE1 and STRE2) and YREs (TRE1 and YRE2) in terms of the activity of a lacZ reporter gene under control of the cTPx II promoter indicates that STRE2 acts as a principal binding element essential for transactivation of the cTPx II promoter. The transcriptional activity of the cTPx II promoter was exponentially increased after postdiauxic growth. The transcriptional activity of the cTPx II promoter is greatly increased by rapamycin. Deletion of Tor1, Tor2, Ras1, and Ras2 resulted in a considerable induction when compared with their parent strains, suggesting that the transcription of cTPx II is under negative control of the Ras/cAMP and target of rapamycin signaling pathways. Taken together, these results suggest that cTPx II is a target of Msn2p/Msn4p transcription factors under negative control of the Ras-protein kinase A and target of rapamycin signaling pathways. Furthermore, the accumulation of cTPx II upon exposure to oxidative stress and during the postdiauxic shift suggests an important antioxidant role in stationary phase yeast cells.

  14. Effects of low power microwave radiation on biological activity of Collagenase enzyme and growth rate of S. Cerevisiae yeast

    Science.gov (United States)

    Alsuhaim, Hamad S.; Vojisavljevic, Vuk; Pirogova, E.

    2013-12-01

    Recently, microwave radiation, a type/subset of non-ionizing electromagnetic radiation (EMR) has been widely used in industry, medicine, as well as food technology and mobile communication. Use of mobile phones is rapidly growing. Four years from now, 5.1 billion people will be mobile phone users around the globe - almost 1 billion more mobile users than the 4.3 billion people worldwide using them now. Consequently, exposure to weak radiofrequency/microwave radiation generated by these devices is markedly increasing. Accordingly, public concern about potential hazards on human health is mounting [1]. Thermal effects of radiofrequency/microwave radiation are very well-known and extensively studied. Of particular interest are non-thermal effects of microwave exposures on biological systems. Nonthermal effects are described as changes in cellular metabolism caused by both resonance absorption and induced EMR and are often accompanied by a specific biological response. Non-thermal biological effects are measurable changes in biological systems that may or may not be associated with adverse health effects. In this study we studied non-thermal effects of low power microwave exposures on kinetics of L-lactate dehydrogenase enzyme and growth rate of yeast Saccharomyces Cerevisiae strains type II. The selected model systems were continuously exposed to microwave radiation at the frequency of 968MHz and power of 10dBm using the designed and constructed (custom made) Transverse Electro-Magnetic (TEM) cell [2]. The findings reveal that microwave radiation at 968MHz and power of 10dBm inhibits L-lactate dehydrogenase enzyme activity by 26% and increases significantly (15%) the proliferation rate of yeast cells.

  15. Lack of HXK2 Induces Localization of Active Ras in Mitochondria and Triggers Apoptosis in the Yeast Saccharomyces cerevisiae

    Directory of Open Access Journals (Sweden)

    Loredana Amigoni

    2013-01-01

    Full Text Available We recently showed that activated Ras proteins are localized to the plasma membrane and in the nucleus in wild-type cells growing exponentially on glucose, while in the hxk2Δ strain they accumulated mainly in mitochondria. An aberrant accumulation of activated Ras in these organelles was previously reported and correlated to mitochondrial dysfunction, accumulation of ROS, and cell death. Here we show that addition of acetic acid to wild-type cells results in a rapid recruitment of Ras-GTP from the nucleus and the plasma membrane to the mitochondria, providing a further proof that Ras proteins might be involved in programmed cell death. Moreover, we show that Hxk2 protects against apoptosis in S. cerevisiae. In particular, cells lacking HXK2 and showing a constitutive accumulation of activated Ras at the mitochondria are more sensitive to acetic-acid-induced programmed cell death compared to the wild type strain. Indeed, deletion of HXK2 causes an increase of apoptotic cells with several morphological and biochemical changes that are typical of apoptosis, including DNA fragmentation, externalization of phosphatidylserine, and ROS production. Finally, our results suggest that apoptosis induced by lack of Hxk2 may not require the activation of Yca1, the metacaspase homologue identified in yeast.

  16. Lack of HXK2 induces localization of active Ras in mitochondria and triggers apoptosis in the yeast Saccharomyces cerevisiae.

    Science.gov (United States)

    Amigoni, Loredana; Martegani, Enzo; Colombo, Sonia

    2013-01-01

    We recently showed that activated Ras proteins are localized to the plasma membrane and in the nucleus in wild-type cells growing exponentially on glucose, while in the hxk2Δ strain they accumulated mainly in mitochondria. An aberrant accumulation of activated Ras in these organelles was previously reported and correlated to mitochondrial dysfunction, accumulation of ROS, and cell death. Here we show that addition of acetic acid to wild-type cells results in a rapid recruitment of Ras-GTP from the nucleus and the plasma membrane to the mitochondria, providing a further proof that Ras proteins might be involved in programmed cell death. Moreover, we show that Hxk2 protects against apoptosis in S. cerevisiae. In particular, cells lacking HXK2 and showing a constitutive accumulation of activated Ras at the mitochondria are more sensitive to acetic-acid-induced programmed cell death compared to the wild type strain. Indeed, deletion of HXK2 causes an increase of apoptotic cells with several morphological and biochemical changes that are typical of apoptosis, including DNA fragmentation, externalization of phosphatidylserine, and ROS production. Finally, our results suggest that apoptosis induced by lack of Hxk2 may not require the activation of Yca1, the metacaspase homologue identified in yeast.

  17. Changes of hydrogen peroxide and radical-scavenging activity of raspberry during osmotic, convective, and freeze-drying.

    Science.gov (United States)

    Novaković, Miroslav M; Stevanović, Snežana M; Gorjanović, Stanislava Ž; Jovanovic, Predrag M; Tešević, Vele V; Janković, Miodrag A; Sužnjević, Desanka Ž

    2011-05-01

    This study was conducted to investigate the influence of different drying treatments on antioxidant (AO) activity and phenolic content of raspberry (Rubus idaeus), cultivar Willamette. Whole raspberry fruits were dried convectively (air-drying), osmotically, and freeze-dried. Acetone-water extracts of fresh and dried raspberries were assessed for total phenolic content by standard Folin-Ciocalteau method. Two AO assays were applied, a recently developed direct current (DC) polarographic assay based on decrease of anodic oxidation current of hydrogen peroxide and widely used radical scavenge against the 1,1-diphenyl-2-picrylhydrazyl (DPPH). Strong correlation has been obtained between both AO assays and total phenolic content. In addition, some individual phenolic compounds present in raspberry have been assessed using DPPH and DC polarographic assay. Comparison and evaluation of drying methods has been based on preservation of AO activity and total phenolic content. Obtained results confirmed superiority of freeze-drying; convective drying caused slight changes while osmotic dehydration showed a significant decrease of phenolic compounds and AO activity. © 2011 Institute of Food Technologists®

  18. Yeast RNA viruses as indicators of exosome activity: human exosome hCsl4p participates in RNA degradation in Saccharomyces cerevisiae'.

    Science.gov (United States)

    Ramírez-Garrastacho, Manuel; Esteban, Rosa

    2011-12-01

    The exosome is an evolutionarily conserved 10-mer complex involved in RNA metabolism, located in both the nucleus and the cytoplasm. The cytoplasmic exosome plays an important role in mRNA turnover through its 3'→5' exonucleolytic activity. The superkiller (SKI) phenotype of yeast was originally identified as an increase of killer toxin production due to elevated levels of the L-A double-stranded RNA (dsRNA) Totivirus and its satellite toxin-encoding M dsRNA. Most SKI genes were later shown to be either components of the exosome or modulators of its activity. Variations in the amount of Totivirus are, thus, good indicators of yeast exosome activity, and can be used to analyse its components. Furthermore, if exosome proteins of higher eukaryotes were functional in S. cerevisiae, these viruses would provide a simple tool to analyse their function. In this work, we have found that hCSL4, the human orthologue of SKI4 in the yeast exosome, rescues the null phenotype of the deletion mutant. hCsl4p shares with Ski4p conserved S1 RNA-binding domains, but lacks the N-terminal third of Ski4p. Nevertheless, it interacts with the Dis3p exonuclease of yeast exosome, and partially complements the superkiller phenotype of ski4-1 mutation. The elimination of the N-terminal third of Ski4p does not affect its activity, indicating that it is dispensable for RNA degradation. We have also identified the point mutation G152E in hCSL4, equivalent to the ski4-1 mutation G253E, which impairs the activity of the protein, thus validating our approach of using yeast RNA virus to analyse the exosome of higher eukaryotes. Copyright © 2011 John Wiley & Sons, Ltd.

  19. Influence of drying conditions on the effective moisture diffusivity, energy of activation and energy consumption during the thin-layer drying of berberis fruit (Berberidaceae)

    Energy Technology Data Exchange (ETDEWEB)

    Aghbashlo, Mortaza; Kianmehr, Mohammad H.; Samimi-Akhijahani, Hadi [Department of Agriculture Machinery, University of Tehran, Aboreyhan Campus (Iran)

    2008-10-15

    Berberis is known as a medicinal and ornamental plant in the world. Berberis fruit is used in medicine to cure liver, neck and stomach cancer, blood purification and mouth scent. Dried berberis fruit using new technology was preserved for relatively long time. Thin-layer drying simulation was used to obtain experiment data, using laboratory scale hot-air dryer of the static tray. Fick's second law was used as a major equation to calculate the moisture diffusivity with some simplification. The calculated value of moisture diffusivity varied from a minimum of 3.320 x 10{sup -10} to a maximum of 9 x 10{sup -9} m{sup 2}/s and the value of energy activation from a minimum of 110.837 to a maximum of 130.61 kJ/mol of from 50 C to 70 C with drying air velocities of 0.5-2 m/s. The high value of the energy of activation for berberis fruit probably related to the tissue of berberis fruit and high moisture content (about 74.28%w.b), and intensive changes in D{sub eff} values for a different air temperature at constant air velocity. The input energy values and specific energy requirement for thin-drying of berberis fruit were found to be in the range of 0.643348-35.20032 (kWh) and 20.9355-1110.0700 (kWh/kg) from 50 C to 70 C with drying air velocities of 0.5-2 m/s, respectively. (author)

  20. Influence of drying conditions on the effective moisture diffusivity, energy of activation and energy consumption during the thin-layer drying of berberis fruit (Berberidaceae)

    International Nuclear Information System (INIS)

    Aghbashlo, Mortaza; Kianmehr, Mohammad H.; Samimi-Akhijahani, Hadi

    2008-01-01

    Berberis is known as a medicinal and ornamental plant in the world. Berberis fruit is used in medicine to cure liver, neck and stomach cancer, blood purification and mouth scent. Dried berberis fruit using new technology was preserved for relatively long time. Thin-layer drying simulation was used to obtain experiment data, using laboratory scale hot-air dryer of the static tray. Fick's second law was used as a major equation to calculate the moisture diffusivity with some simplification. The calculated value of moisture diffusivity varied from a minimum of 3.320 x 10 -10 to a maximum of 9 x 10 -9 m 2 /s and the value of energy activation from a minimum of 110.837 to a maximum of 130.61 kJ/mol of from 50 deg. C to 70 deg. C with drying air velocities of 0.5-2 m/s. The high value of the energy of activation for berberis fruit probably related to the tissue of berberis fruit and high moisture content (about 74.28%w.b), and intensive changes in D eff values for a different air temperature at constant air velocity. The input energy values and specific energy requirement for thin-drying of berberis fruit were found to be in the range of 0.643348-35.20032 (kWh) and 20.9355-1110.0700 (kWh/kg) from 50 deg. C to 70 deg. C with drying air velocities of 0.5-2 m/s, respectively

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

    Science.gov (United States)

    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.

  2. HSF and Msn2/4p can exclusively or cooperatively activate the yeast HSP104 gene.

    Science.gov (United States)

    Grably, Melanie R; Stanhill, Ariel; Tell, Osnat; Engelberg, David

    2002-04-01

    In an effort to understand how an accurate level of stress-specific expression is obtained, we studied the promoter of the yeast HSP104 gene. Through 5' deletions, we defined a 334 bp fragment upstream of the first coding AUG as sufficient and essential for maximal basal activity and a 260 bp fragment as sufficient and essential for heat shock responsiveness. These sequences contain heat shock elements (HSEs) and stress response elements (STREs) that cooperate to achieve maximal inducible expression. However, in the absence of one set of factors (e.g. in msn2Deltamsn4Delta cells) proper induction is obtained exclusively through HSEs. We also show that HSP104 is constitutively derepressed in ras2Delta cells. This derepression is achieved exclusively through activation of STREs, with no role for HSEs. Strikingly, in ras2Deltamsn2Deltamsn4Delta cells the HSP104 promoter is also derepressed, but in this strain derepression is mediated through HSEs, showing the flexibility and adaptation of the promoter. Thus, appropriate transcription of HSP104 is usually obtained through cooperation between the Msn2/4/STRE and the HSF/ HSE systems, but each factor could activate the promoter alone, backing up the other. Transcription control of HSP104 is adaptive and robust, ensuring proper expression under extreme conditions and in various mutants.

  3. Correlation of antioxidant activity of dried berry infusions with the polyphenols and selected microelements contents

    Directory of Open Access Journals (Sweden)

    M. M. Bratu

    2018-04-01

    Full Text Available Antioxidant activity was measured by ferric reducing ability of plasma (FRAP assay in seven types of infusions prepared from commercial dried berry fruit products: Rosa canina, Vaccinium vitis-idaea, Hiphophae rhamnoides, Hibiscus sabdariffa and three fruit mixtures. Total polyphenols (TP, total anthocyanins and the polyphenolic compounds were determined by HPLC equipped with diode array detector. To estimate the amount of elements released from fruits into the water extracts, levels of Fe, Mn, Zn and Cu in dried samples and in infusions were determined by flame atomic absorption spectrometry. The correlation between polyphenols content and the antioxidant activities and the microelements in the infusions and the antioxidant activities were estimated using the Pearson’s correlation test. The results showed a high, positive and significant correlation (r = 0.9465 between the FRAP values and TP content, meaning that the concentration of phenolic compounds may be a good indicator of the reducing capacity in the infusions. Correlations varied (positive, negative and weak between antioxidant and mineral extractability of berry infusions. Among the polyphenolic compounds, gallic acid contributed particularly to the antioxidant capacity of the studied samples (r = 0.563. The correlation of antioxidants, total polyphenols with mineral extractability showed the influence of antioxidant compound on mineral bioavailability.

  4. Mediator, TATA-binding protein, and RNA polymerase II contribute to low histone occupancy at active gene promoters in yeast.

    Science.gov (United States)

    Ansari, Suraiya A; Paul, Emily; Sommer, Sebastian; Lieleg, Corinna; He, Qiye; Daly, Alexandre Z; Rode, Kara A; Barber, Wesley T; Ellis, Laura C; LaPorta, Erika; Orzechowski, Amanda M; Taylor, Emily; Reeb, Tanner; Wong, Jason; Korber, Philipp; Morse, Randall H

    2014-05-23

    Transcription by RNA polymerase II (Pol II) in eukaryotes requires the Mediator complex, and often involves chromatin remodeling and histone eviction at active promoters. Here we address the role of Mediator in recruitment of the Swi/Snf chromatin remodeling complex and its role, along with components of the preinitiation complex (PIC), in histone eviction at inducible and constitutively active promoters in the budding yeast Saccharomyces cerevisiae. We show that recruitment of the Swi/Snf chromatin remodeling complex to the induced CHA1 promoter, as well as its association with several constitutively active promoters, depends on the Mediator complex but is independent of Mediator at the induced MET2 and MET6 genes. Although transcriptional activation and histone eviction at CHA1 depends on Swi/Snf, Swi/Snf recruitment is not sufficient for histone eviction at the induced CHA1 promoter. Loss of Swi/Snf activity does not affect histone occupancy of several constitutively active promoters; in contrast, higher histone occupancy is seen at these promoters in Mediator and PIC component mutants. We propose that an initial activator-dependent, nucleosome remodeling step allows PIC components to outcompete histones for occupancy of promoter sequences. We also observe reduced promoter association of Mediator and TATA-binding protein in a Pol II (rpb1-1) mutant, indicating mutually cooperative binding of these components of the transcription machinery and indicating that it is the PIC as a whole whose binding results in stable histone eviction. © 2014 by The American Society for Biochemistry and Molecular Biology, Inc.

  5. The Association between Dry Eye Disease and Physical Activity as well as Sedentary Behavior: Results from the Osaka Study

    OpenAIRE

    Kawashima, Motoko; Uchino, Miki; Yokoi, Norihiko; Uchino, Yuichi; Dogru, Murat; Komuro, Aoi; Sonomura, Yukiko; Kato, Hiroaki; Nishiwaki, Yuji; Kinoshita, Shigeru; Tsubota, Kazuo

    2014-01-01

    Purpose. To assess the association of dry eye disease (DED) with physical activity and sedentary behavior. Methods. The cross-sectional survey conducted included Japanese office workers who use visual display terminals (n = 672). DED was assessed according to the Japanese Dry Eye Diagnostic Criteria, and participants were categorized into “definite DED,” “probable DED,” or “non-DED” groups based on the results of DED examinations. Physical activity and sedentary behavior of participants were ...

  6. Synthesis of polypyrrole within the cell wall of yeast by redox-cycling of [Fe(CN)6](3-)/[Fe(CN)6](4-).

    Science.gov (United States)

    Ramanavicius, Arunas; Andriukonis, Eivydas; Stirke, Arunas; Mikoliunaite, Lina; Balevicius, Zigmas; Ramanaviciene, Almira

    2016-02-01

    Yeast cells are often used as a model system in various experiments. Moreover, due to their high metabolic activity, yeast cells have a potential to be applied as elements in the design of biofuel cells and biosensors. However a wider application of yeast cells in electrochemical systems is limited due to high electric resistance of their cell wall. In order to reduce this problem we have polymerized conducting polymer polypyrrole (Ppy) directly in the cell wall and/or within periplasmic membrane. In this research the formation of Ppy was induced by [Fe(CN)6](3-)ions, which were generated from K4[Fe(CN)6], which was initially added to polymerization solution. The redox process was catalyzed by oxido-reductases, which are present in the plasma membrane of yeast cells. The formation of Ppy was confirmed by spectrophotometry and atomic force microscopy. It was confirmed that the conducting polymer polypyrrole was formed within periplasmic space and/or within the cell wall of yeast cells, which were incubated in solution containing pyrrole, glucose and [Fe(CN)6](4-). After 24h drying at room temperature we have observed that Ppy-modified yeast cell walls retained their initial spherical form. In contrast to Ppy-modified cells, the walls of unmodified yeast have wrinkled after 24h drying. The viability of yeast cells in the presence of different pyrrole concentrations has been evaluated. Copyright © 2015 Elsevier Inc. All rights reserved.

  7. Potato dextrose agar antifungal susceptibility testing for yeasts and molds: evaluation of phosphate effect on antifungal activity of CMT-3.

    Science.gov (United States)

    Liu, Yu; Tortora, George; Ryan, Maria E; Lee, Hsi-Ming; Golub, Lorne M

    2002-05-01

    The broth macrodilution method (BMM) for antifungal susceptibility testing, approved by the National Committee for Clinical Laboratory Standards (NCCLS), was found to have deficiencies in testing of the antifungal activity of a new type of antifungal agent, a nonantibacterial chemically modified tetracycline (CMT-3). The high content of phosphate in the medium was found to greatly increase the MICs of CMT-3. To avoid the interference of phosphate in the test, a new method using potato dextrose agar (PDA) as a culture medium was developed. Eight strains of fungi, including five American Type Culture Collection strains and three clinical isolates, were used to determine the MICs of amphotericin B and itraconazole with both the BMM and the PDA methods. The MICs of the two antifungal agents determined with the PDA method showed 99% agreement with those determined with the BMM method within 1 log(2) dilution. Similarly, the overall reproducibility of the MICs with the PDA method was above 97%. Three other antifungal agents, fluconazole, ketoconazole, and CMT-3, were also tested in parallel against yeasts and molds with both the BMM and the PDA methods. The MICs of fluconazole and ketoconazole determined with the PDA method showed 100% agreement within 1 log(2) dilution of those obtained with the BMM method. However, the MICs of CMT-3 determined with the BMM method were as high as 128 times those determined with the PDA method. The effect of phosphate on the antifungal activity of CMT-3 was evaluated by adding Na2HPO4 to PDA in the new method. It was found that the MIC of CMT-3 against a Penicillium sp. increased from 0.5 microg/ml (control) to 2.0 microg/ml when the added phosphate was used at a concentration of 0.8 mg/ml, indicating a strong interference of Na2HPO4 with the antifungal activity of CMT-3. Except for fluconazole, all the other antifungal agents demonstrated clear end points among the yeasts and molds tested. Nevertheless, with its high reproducibility

  8. Antifungal activity of phlorotannins against dermatophytes and yeasts: approaches to the mechanism of action and influence on Candida albicans virulence factor.

    Directory of Open Access Journals (Sweden)

    Graciliana Lopes

    Full Text Available In the last few decades, fungal infections, particularly nosocomial, increased all around the world. This increment stimulated the search for new antifungal agents, especially those derived from nature. Among natural products, those from marine sources have gained prominence in the last years. Purified phlorotannins extracts from three brown seaweeds (Cystoseira nodicaulis (Withering M. Roberts, Cystoseira usneoides (Linnaeus M. Roberts and Fucus spiralis Linnaeus were screened for their antifungal activity against human pathogenic yeast and filamentous fungi. The purified phlorotannins extracts from the studied seaweeds displayed fungistatic and fungicidal activity against yeast and dermatophytes, respectively, pointing to their interest as anti-dermatophyte agent. C. albicans ATCC 10231 was the most susceptible among yeast, while Epidermophyton floccosum and Trichophyton rubrum were the most susceptible among dermatophytes. Since the antifungal mechanism constitutes an important strategy for limiting the emergence of resistance to the commercially available agents, the mechanism of action of purified phlorotannins extracts was approached. C. nodicaulis and C. usneoides seem to act by affecting the ergosterol composition of the cell membrane of yeast and dermatophyte, respectively. F. spiralis influenced the dermatophyte cell wall composition by reducing the levels of chitin. Phlorotannins also seem to affect the respiratory chain function, as all of the studied species significantly increased the activity of mitochondrial dehydrogenases and increased the incorporation of rhodamine 123 by yeast cells. Phlorotannins from F. spiralis inhibited the dimorphic transition of Candida albicans, leading to the formation of pseudohyphae with diminished capacity to adhere to epithelial cells. This finding is associated with a decrease of C. albicans virulence and capacity to invade host cells and can be potentially interesting for combined antifungal

  9. Adsorption of mercury by activated carbon prepared from dried sewage sludge in simulated flue gas.

    Science.gov (United States)

    Park, Jeongmin; Lee, Sang-Sup

    2018-04-25

    Conversion of sewage sludge to activated carbon is attractive as an alternative method to ocean dumping for the disposal of sewage sludge. Injection of activated carbon upstream of particulate matter control devices has been suggested as a method to remove elemental mercury from flue gas. Activated carbon was prepared using various activation temperatures and times and was tested for their mercury adsorption efficiency using lab-scale systems. To understand the effect of the physical property of the activated carbon, its mercury adsorption efficiency was investigated as a function of their Brunauer-Emmett-Teller (BET) surface area. Two simulated flue gas conditions: (1) without hydrogen chloride (HCl) and (2) with 20 ppm HCl, were used to investigate the effect of flue gas composition on the mercury adsorption capacity of activated carbon. Despite very low BET surface area of the prepared sewage sludge activated carbons, their mercury adsorption efficiencies were comparable under both simulated flue gas conditions to those of pinewood and coal activated carbons. After injecting HCl into the simulated flue gas, all sewage sludge activated carbons demonstrated high adsorption efficiencies, i.e., more than 87%, regardless of their BET surface area. IMPLICATIONS We tested activated carbons prepared from dried sewage sludge to investigate the effect of their physical properties on their mercury adsorption efficiency. Using two simulated flue gas conditions, we conducted mercury speciation for the outlet gas. We found that the sewage sludge activated carbon had comparable mercury adsorption efficiency to pinewood and coal activated carbons, and the presence of HCl minimized the effect of physical property of the activated carbon on its mercury adsorption efficiency.

  10. In vitro ability of beer fermentation residue and yeast-based products to bind aflatoxin B1.

    Science.gov (United States)

    Bovo, Fernanda; Franco, Larissa Tuanny; Rosim, Roice Eliana; Barbalho, Ricardo; de Oliveira, Carlos Augusto Fernandes

    2015-06-01

    This study aimed to verify the in vitro ability of beer fermentation residue (BFR) containing Saccharomyces cerevisiae cells and five commercial products that differed in the viability and integrity of S. cerevisiae cells to remove aflatoxin B1 (AFB1) from a citrate-phosphate buffer solution (CPBS). BFR was collected at a microbrewery and prepared by drying and milling. The commercial yeast-based products were as follows: inactive intact yeast cells from beer alcoholic fermentation, inactive intact yeast cells from sugarcane alcoholic fermentation, hydrolyzed yeast cells, yeast cell walls and active yeast cells. Adsorption assays were performed in CPBS spiked with 1.0 μg AFB1/mL at pH 3.0 and 6.0 for a contact time of 60 min at room temperature. Analysis of AFB1 in the samples was performed by high performance liquid chromatography. AFB1 adsorption by the products ranged from 45.5% to 69.4% at pH 3.0 and from 24.0% to 63.8% at pH 6.0. The higher percentages (p 0.05) from commercial products containing inactive intact yeast cells. The results of this trial indicate that the yeast-based products tested, especially the BFR, have potential applications in animal feeds as a suitable biological method for reducing the adverse effects of aflatoxins.

  11. In vitro ability of beer fermentation residue and yeast-based products to bind aflatoxin B1

    Directory of Open Access Journals (Sweden)

    Fernanda Bovo

    2015-06-01

    Full Text Available This study aimed to verify the in vitro ability of beer fermentation residue (BFR containing Saccharomyces cerevisiae cells and five commercial products that differed in the viability and integrity of S. cerevisiae cells to remove aflatoxin B1 (AFB1 from a citrate-phosphate buffer solution (CPBS. BFR was collected at a microbrewery and prepared by drying and milling. The commercial yeast-based products were as follows: inactive intact yeast cells from beer alcoholic fermentation, inactive intact yeast cells from sugarcane alcoholic fermentation, hydrolyzed yeast cells, yeast cell walls and active yeast cells. Adsorption assays were performed in CPBS spiked with 1.0 μg AFB1/mL at pH 3.0 and 6.0 for a contact time of 60 min at room temperature. Analysis of AFB1 in the samples was performed by high performance liquid chromatography. AFB1 adsorption by the products ranged from 45.5% to 69.4% at pH 3.0 and from 24.0% to 63.8% at pH 6.0. The higher percentages (p 0.05 from commercial products containing inactive intact yeast cells. The results of this trial indicate that the yeast-based products tested, especially the BFR, have potential applications in animal feeds as a suitable biological method for reducing the adverse effects of aflatoxins.

  12. Low-level dry active waste management planning for Calvert Cliffs Nuclear Power Plant

    International Nuclear Information System (INIS)

    Butler, C.N.; Feizollani, F.; Jarboe, Th.B.

    1984-01-01

    To offset the rising cost of low-level radioactive waste disposal and to provide contingency measures for disposal space unavailability after January 1, 1986, Baltimore Gas and Electric (BG and E) has undertake efforts to establish a long-term waste management program. This plan, which was developed after detailed study of a number of options, consists of four elements: management of dry active wastes; implementation of 10CFR61 requirements; storage of process wastes; and enhancement of liquid/solid waste systems and equipment performance. Each element was scheduled for implementation in accordance with an established set of priorities. Accordingly, detailed engineering for implementation of the first two elements was initiated in December of 1982. This paper focuses on BGandE's experience in implementation of the first element o the program, i.e., the management of dry active waste (DAW). DAW is managed by providing a new buildin dedicated to its handling, processing, volume-reduction, and storage. This building, which is equipped with state-of-the-art decontamination and processing techniques, allows for implementation of waste minimization and for interim storage of DAW in a safe and cost effective manner

  13. Dry reforming of coke oven gases over activated carbon to produce syngas for methanol synthesis

    Energy Technology Data Exchange (ETDEWEB)

    J.M. Bermudez; B. Fidalgo; A. Arenillas; J.A. Menendez [Instituto Nacional del Carbn, Oviedo (Spain)

    2010-10-15

    The dry reforming of coke oven gases (COG) over an activated carbon used as catalyst has been studied in order to produce a syngas suitable for methanol synthesis. The primary aim of this work was to study the influence of the high amount of hydrogen present in the COG on the process of dry reforming, as well as the influence of other operation conditions, such us temperature and volumetric hourly space velocity (VHSV). It was found that the reverse water gas shift (RWGS) reaction takes place due to the hydrogen present in the COG, and that its influence on the process increases as the temperature decreases. This situation may give rise to the consumption of the hydrogen present in the COG, and the consequent formation of a syngas which is inappropriate for the synthesis of methanol. This reaction can be avoided by working at high temperatures (about 1000{sup o}C) in order to produce a syngas that is suitable for methanol synthesis. It was also found that the RWGS reaction is favoured by an increase in the VHSV. In addition, the active carbon FY5 was proven to be an adequate catalyst for the production of syngas from COG. 25 refs., 7 figs., 2 tabs.

  14. Results of full scale dry injection tests at MSW-incinerators using a new active absorbent

    International Nuclear Information System (INIS)

    Felsvang, K.S.; Helvind, O.

    1991-01-01

    Worldwide incineration of municipal solid waste (MSW) has been utilized to reduce the volume of waste to be disposed of. Increasing environmental concerns over the potential air pollution impacts have led to emission limits for pollutants such as HCl, SO 2 , particulate, and more recently also for mercury and dioxins. For a certain size of incinerators, dry sorbent injection is the preferred technology for air pollution control. This paper describes the development of a new active sorbent, Scansorb, which is particularly suited for use in dry injection processes. The new sorbent is a lime based product with adjustable properties. Scansorb can be produced with a specific surface area of 30 to 100 m 2 /g. Pilot plant development work has shown that a considerable reduction in the absorbent quantity can be achieved when Scansorb is used instead of commercial hydrated lime. Full scale tests performed at four different MSW incinerators have confirmed the viability of the new active absorbent. The full scale tests have demonstrated that more than 50% SO 2 removal can be achieved with Scansorb at quantities much less than with commercial hydrated lime

  15. Constitutive Activation of the Fission Yeast Pheromone-Responsive Pathway Induces Ectopic Meiosis and Reveals Ste11 as a Mitogen-Activated Protein Kinase Target

    DEFF Research Database (Denmark)

    Kjærulff, Søren; Lautrup-Larsen, I.; Truelsen, S.

    2005-01-01

    In the fission yeast Schizosaccharomyces pombe, meiosis normally takes place in diploid zygotes resulting from conjugation of haploid cells. In the present study, we report that the expression of a constitutively activated version of the pheromone-responsive mitogen-activated protein kinase kinase...... found that haploid meiosis was dramatically reduced when Ste11 was mutated to mimic phosphorylation by Pat1. The mutation of two putative MAPK sites in Ste11 also dramatically reduced the level of haploid meiosis, suggesting that Ste11 is a direct target of Spk1. Supporting this, we show that Spk1 can...... interact physically with Ste11 and also phosphorylate the transcription factor in vitro. Finally, we demonstrate that ste11 is required for pheromone-induced G1 arrest. Interestingly, when we mutated Ste11 in the sites for Pat1 and Spk1 phosphorylation simultaneously, the cells could still arrest in G1...

  16. VID22 is required for transcriptional activation of the PSD2 gene in the yeast Saccharomyces cerevisiae.

    Science.gov (United States)

    Miyata, Non; Miyoshi, Takuya; Yamaguchi, Takanori; Nakazono, Toshimitsu; Tani, Motohiro; Kuge, Osamu

    2015-12-15

    Phosphatidylethanolamine (PE) in the yeast Saccharomyces cerevisiae is synthesized through decarboxylation of phosphatidylserine (PS), catalysed by PS decarboxylase 1 (Psd1p) and 2 (Psd2p) and the cytidine 5'-diphosphate (CDP)-ethanolamine (CDP-Etn) pathway. PSD1 null (psd1Δ) and PSD2 null (psd2Δ) mutants are viable in a synthetic minimal medium, but a psd1Δ psd2Δ double mutant exhibits Etn auxotrophy, which is incorporated into PE through the CDP-Etn pathway. We have previously shown that psd1Δ is synthetic lethal with deletion of VID22 (vid22Δ) [Kuroda et al. (2011) Mol. Microbiol. 80: , 248-265]. In the present study, we found that vid22Δ mutant exhibits Etn auxotrophy under PSD1-depressed conditions. Deletion of VID22 in wild-type and PSD1-depressed cells caused partial defects in PE formation through decarboxylation of PS. The enzyme activity of PS decarboxylase in an extract of vid22Δ cells was ∼70% of that in wild-type cells and similar to that in psd2Δ cells and the PS decarboxylase activity remaining in the PSD1-depressed cells became almost negligible with deletion of VID22. Thus, the vid22Δ mutation was suggested to cause a defect in the Psd2p activity. Furthermore, vid22Δ cells were shown to be defective in expression of the PSD2 gene tagged with 6×HA, the defect being ameliorated by replacement of the native promoter of the PSD2 gene with a CYC1 promoter. In addition, an α-galactosidase reporter assay revealed that the activity of the promoter of the PSD2 gene in vid22Δ cells was ∼5% of that in wild-type cells. These results showed that VID22 is required for transcriptional activation of the PSD2 gene. © 2015 Authors; published by Portland Press Limited.

  17. Impact of yeast starter formulations on the production of volatile compounds during wine fermentation.

    Science.gov (United States)

    Romano, Patrizia; Pietrafesa, Rocchina; Romaniello, Rossana; Zambuto, Marianna; Calabretti, Antonella; Capece, Angela

    2015-01-01

    The most diffused starter formulation in winemaking is actually represented by active dry yeast (ADY). Spray-drying has been reported as an appropriate preservation method for yeast and other micro-organisms. Despite the numerous advantages of this method, the high air temperatures used can negatively affect cell viability and the fermentative performance of dried cells. In the present study, 11 wine S. cerevisiae strains (both indigenous and commercial) were submitted to spray-drying; different process conditions were tested in order to select the conditions allowing the highest strain survival. The strains exhibited high variability for tolerance to spray-drying treatment. Selected strains were tested in fermentation at laboratory scale in different formulations (free fresh cells, free dried cells, immobilized fresh cells and immobilized dried cells), in order to assess the influence of starter formulation on fermentative fitness of strains and aromatic quality of wine. The analysis of volatile fraction in the experimental wines produced by selected strains in different formulations allowed identification of > 50 aromatic compounds (alcohols, esters, ketones, aldehydes and terpenes). The results obtained showed that the starter formulation significantly influenced the content of volatile compounds. In particular, the wines obtained by strains in dried forms (as both free and immobilized cells) contained higher numbers of volatile compounds than wines obtained from fresh cells. Copyright © 2014 John Wiley & Sons, Ltd.

  18. Biotechnological production of high specific activity L-35S-cysteine and L-35S-methionine by using a diploid yeast Saccharomyces cerevisiae

    International Nuclear Information System (INIS)

    Gajendiran, N.; Jayachandran, N.; Unny, V.K.P.; Thyagarajan, S.; Rao, B.S.

    1994-01-01

    High specific activity L- 3 5 S-cysteine and L- 35 S-methionine were synthesised by using a wild type diploid strain of baker's yeast-Saccharomyces cerevisiae. Yeast cells were grown in a sulphur depleted synthetic medium in which Na 2 3 5 SO 4 (50 mCi/ml) was supplemented as the sole sulphur source. The level of incorporation was 60% on an average. The protein hydrolysate of the cultured cells was subjected to paper and column chromatographic separations to get the individual L- 3 5 S-aminoacids. The radiochemical yields of cysteine and methionine were 6-7% and 18-20% respectively. The radiochemical purity of the products was >95%. The highest specific activity for the products obtained by employing this method was 1100 Ci/mmole from the starting material, Na 2 35 SO 4 , with a specific activity of 1350 Ci/mmole. (Author)

  19. Dry, portable calorimeter for nondestructive measurement of the activity of nuclear fuel

    Science.gov (United States)

    Beyer, Norman S.; Lewis, Robert N.; Perry, Ronald B.

    1976-01-01

    The activity of a quantity of heat-producing nuclear fuel is measured rapidly, accurately and nondestructively by a portable dry calorimeter comprising a preheater, an array of temperature-controlled structures comprising a thermally guarded temperature-controlled oven, and a calculation and control unit. The difference between the amounts of electric power required to maintain the oven temperature with and without nuclear fuel in the oven is measured to determine the power produced by radioactive disintegration and hence the activity of the fuel. A portion of the electronic control system is designed to terminate a continuing sequence of measurements when the standard deviation of the variations of the amount of electric power required to maintain oven temperature is within a predetermined value.

  20. Bacterial community composition and extracellular enzyme activity in temperate streambed sediment during drying and rewetting.

    Directory of Open Access Journals (Sweden)

    Elisabeth Pohlon

    Full Text Available Droughts are among the most important disturbance events for stream ecosystems; they not only affect stream hydrology but also the stream biota. Although desiccation of streams is common in Mediterranean regions, phases of dryness in headwaters have been observed more often and for longer periods in extended temperate regions, including Central Europe, reflecting global climate change and enhanced water withdrawal. The effects of desiccation and rewetting on the bacterial community composition and extracellular enzyme activity, a key process in the carbon flow of streams and rivers, were investigated in a typical Central European stream, the Breitenbach (Hesse, Germany. Wet streambed sediment is an important habitat in streams. It was sampled and exposed in the laboratory to different drying scenarios (fast, intermediate, slow for 13 weeks, followed by rewetting of the sediment from the fast drying scenario via a sediment core perfusion technique for 2 weeks. Bacterial community structure was analyzed using CARD-FISH and TGGE, and extracellular enzyme activity was assessed using fluorogenic model substrates. During desiccation the bacterial community composition shifted toward composition in soil, exhibiting increasing proportions of Actinobacteria and Alphaproteobacteria and decreasing proportions of Bacteroidetes and Betaproteobacteria. Simultaneously the activities of extracellular enzymes decreased, most pronounced with aminopeptidases and less pronounced with enzymes involved in the degradation of polymeric carbohydrates. After rewetting, the general ecosystem functioning, with respect to extracellular enzyme activity, recovered after 10 to 14 days. However, the bacterial community composition had not yet achieved its original composition as in unaffected sediments within this time. Thus, whether the bacterial community eventually recovers completely after these events remains unknown. Perhaps this community undergoes permanent changes

  1. Cdc7 is required throughout the yeast S phase to activate replication origins.

    Science.gov (United States)

    Donaldson, A D; Fangman, W L; Brewer, B J

    1998-02-15

    The long-standing conclusion that the Cdc7 kinase of Saccharomyces cerevisiae is required only to trigger S phase has been challenged by recent data that suggests it acts directly on individual replication origins. We tested the possibility that early- and late-activated origins have different requirements for Cdc7 activity. Cells carrying a cdc7(ts) allele were first arrested in G1 at the cdc7 block by incubation at 37 degrees C, and then were allowed to enter S phase by brief incubation at 23 degrees C. During the S phase, after return to 37 degrees C, early-firing replication origins were activated, but late origins failed to fire. Similarly, a plasmid with a late-activated origin was defective in replication. As a consequence of the origin activation defect, duplication of chromosomal sequences that are normally replicated from late origins was greatly delayed. Early-replicating regions of the genome duplicated at approximately their normal time. The requirements of early and late origins for Cdc7 appear to be temporally rather than quantitatively different, as reducing overall levels of Cdc7 by growth at semi-permissive temperature reduced activation at early and late origins approximately equally. Our results show that Cdc7 activates early and late origins separately, with late origins requiring the activity later in S phase to permit replication initiation.

  2. Bioethanol production from dried sweet sorghum stalk

    Energy Technology Data Exchange (ETDEWEB)

    Almodares, A.; Etemadifar, Z.; Ghoreishi, F.; Yosefi, F. [Biology Dept. Univ. of Isfahan, Isfahan (Iran, Islamic Republic of)], e-mail: aalmodares@yahoo.com

    2012-11-01

    Bioethanol as a renewable transportation fuel has a great potential for energy and clean environment. Among crops sweet sorghum is one of the best feedstock for ethanol production under hot and dry climatic conditions. Because it has higher tolerance to salt and drought comparing to sugarcane and corn that are currently used for bio-fuel production in the world. Generally mills are used to extract the juice from sweet sorghum stalks. Three roller mills extract around nearly 50 percent of the juice and more mills is needed to extract higher percentage of the juice. More over under cold weather the stalks become dry and juice is not extracted from the stalk, therefore reduce harvesting period. In this study stalks were harvested, leaves were stripped from the stalks and the stalks were chopped to nearly 4 mm length and sun dried. The dry stalks were grounded to 60 mesh powder by a mill. Fermentation medium consists of 15-35% (w/w) sweet sorghum powder, micronutrients and active yeast inoculum from 0.5-1% (w/w) by submerge fermentation method. The fermentation time and temperature were 48-72 hours and 30 deg, respectively. The results showed the highest amount of ethanol (14.5 % w/w sorghum) was produced with 10% sweet sorghum powder and 1% of yeast inoculum, three day fermentation at 30 deg.

  3. Effects of Flexible Dry Electrode Design on Electrodermal Activity Stimulus Response Detection.

    Science.gov (United States)

    Haddad, Peter A; Servati, Amir; Soltanian, Saeid; Ko, Frank; Servati, Peyman

    2017-12-01

    The focus of this research is to evaluate the effects of design parameters including surface area, distance between and geometry of dry flexible electrodes on electrodermal activity (EDA) stimulus response detection. EDA is a result of the autonomic nervous system being stimulated, which causes sweat and changes the electrical characteristics of the skin. Standard silver/silver chloride (Ag/AgCl) EDA electrodes are rigid and lack conformability in contact with skin. In this study, flexible dry Ag/AgCl EDA electrodes were fabricated on a compliant substrate, used to monitor EDA stimulus responses and compared to results simultaneously collected by rigid dry Ag/AgCl electrodes. A repeatable fabrication process for flexible Ag/AgCl electrodes has been established. Surface area, distance between and geometry of electrodes are shown to affect the detectability of the EDA response and the minimum number of sweat glands to be covered by the electrodes has been estimated at 140, or more, in order to maintain functionality. The optimal flexible EDA electrode is a serpentine design with a 0.15 cm 2 surface area and a 0.20 cm distance with an average Pearson correlation coefficient of . Fabrication of flexible electrodes is described and an understanding of the effects of electrode designs on the EDA stimulus response detection has been established and is potentially related to the coverage of sweat glands. This work presents a novel systematic approach to understand the effects of electrode designs on monitoring EDA which is of importance for the design of wearable EDA monitoring devices.

  4. Beneficial Effect of Brewers' Yeast Extract on Daily Activity in a Murine Model of Chronic Fatigue Syndrome

    Directory of Open Access Journals (Sweden)

    Takashi Takahashi

    2006-01-01

    Full Text Available The aim of this study was to assess the effect of Brewers' yeast extract (BYE on daily activity in a mouse model of chronic fatigue syndrome (CFS. CFS was induced by repeated injection of Brucella abortus (BA antigen every 2 weeks. BYE was orally administered to mice in a dose of 2 g per kg per day for 2 weeks before injecting BA and for 4 weeks thereafter. We evaluated daily running activity in mice receiving BYE as compared with that in untreated mice. Weekly variation of body weight (BW and survival in both groups was monitored during the observation period. Spleen weight (SW, SW/BW ratio, percent splenic follicular area and expression levels of interferon-γ (IFN-γ and interleukin-10 (IL-10 mRNA in spleen were determined in both groups at the time of sacrifice. The daily activity during 2 weeks after the second BA injection was significantly higher in the treated group than in the control. There was no difference in BW between both groups through the experimental course. Two mice in the control died 2 and 7 days after the second injection, whereas no mice in the treated group died. Significantly decreased SW and SW/BW ratio were observed in the treated mice together with elevation of splenic follicular area. There were suppressed IFN-γ and IL-10 mRNA levels in spleens from the treated mice. Our results suggest that BYE might have a protective effect on the marked reduction in activity following repeated BA injection via normalization of host immune responses.

  5. In Vitro Activity of E1210, a Novel Antifungal, against Clinically Important Yeasts and Molds▿

    Science.gov (United States)

    Miyazaki, Mamiko; Horii, Takaaki; Hata, Katsura; Watanabe, Nao-aki; Nakamoto, Kazutaka; Tanaka, Keigo; Shirotori, Syuji; Murai, Norio; Inoue, Satoshi; Matsukura, Masayuki; Abe, Shinya; Yoshimatsu, Kentaro; Asada, Makoto

    2011-01-01

    E1210 is a new antifungal compound with a novel mechanism of action and broad spectrum of antifungal activity. We investigated the in vitro antifungal activities of E1210 compared to those of fluconazole, itraconazole, voriconazole, amphotericin B, and micafungin against clinical fungal isolates. E1210 showed potent activities against most Candida spp. (MIC90 of ≤0.008 to 0.06 μg/ml), except for Candida krusei (MICs of 2 to >32 μg/ml). E1210 showed equally potent activities against fluconazole-resistant and fluconazole-susceptible Candida strains. E1210 also had potent activities against various filamentous fungi, including Aspergillus fumigatus (MIC90 of 0.13 μg/ml). E1210 was also active against Fusarium solani and some black molds. Of note, E1210 showed the greatest activities against Pseudallescheria boydii (MICs of 0.03 to 0.13 μg/ml), Scedosporium prolificans (MIC of 0.03 μg/ml), and Paecilomyces lilacinus (MICs of 0.06 μg/ml) among the compounds tested. The antifungal action of E1210 was fungistatic, but E1210 showed no trailing growth of Candida albicans, which has often been observed with fluconazole. In a cytotoxicity assay using human HK-2 cells, E1210 showed toxicity as low as that of fluconazole. Based on these results, E1210 is likely to be a promising antifungal agent for the treatment of invasive fungal infections. PMID:21825291

  6. Swarm motility inhibitory and antioxidant activities of pomegranate peel processed under three drying conditions.

    Science.gov (United States)

    John, K M Maria; Bhagwat, Arvind A; Luthria, Devanand L

    2017-11-15

    During processing of ready-to-eat fresh fruits, large amounts of peel and seeds are discarded as waste. Pomegranate (Punicagranatum) peels contain high amounts of bioactive compounds which inhibit migration of Salmonella on wet surfaces. The metabolic distribution of bioactives in pomegranate peel, inner membrane, and edible aril portion was investigated under three different drying conditions along with the anti-swarming activity against Citrobacter rodentium. Based on the multivariate analysis, 29 metabolites discriminated the pomegranate peel, inner membrane, and edible aril portion, as well as the three different drying methods. Punicalagins (∼38.6-50.3mg/g) were detected in higher quantities in all fractions as compared to ellagic acid (∼0.1-3.2mg/g) and punicalins (∼0-2.4mg/g). The bioactivity (antioxidant, anti-swarming) and phenolics content was significantly higher in peels than the edible aril portion. Natural anti-swarming agents from food waste may have promising potential for controlling food borne pathogens. Published by Elsevier Ltd.

  7. Thailandins A and B, New Polyene Macrolactone Compounds Isolated from Actinokineospora bangkokensis Strain 44EHW(T), Possessing Antifungal Activity against Anthracnose Fungi and Pathogenic Yeasts.

    Science.gov (United States)

    Intra, Bungonsiri; Greule, Anja; Bechthold, Andreas; Euanorasetr, Jirayut; Paululat, Thomas; Panbangred, Watanalai

    2016-06-29

    Two new polyene macrolactone antibiotics, thailandins A, 1, and B, 2, were isolated from the fermentation broth of rhizosphere soil-associated Actinokineospora bangkokensis strain 44EHW(T). The new compounds from this strain were purified using semipreparative HPLC and Sephadex LH-20 gel filtration while following an antifungal activity guided fractionation. Their structures were elucidated through spectroscopic techniques including UV, HR-ESI-MS, and NMR. These compounds demonstrated broad spectrum antifungal activity against fungi causing anthracnose disease (Colletotrichum gloeosporioides DoA d0762, Colletotrichum gloeosporiodes DoA c1060, and Colletotrichum capsici DoA c1511) as well as pathogenic yeasts (Candida albicans MT 2013/1, Candida parasilopsis DKMU 434, and Cryptococcus neoformans MT 2013/2) with minimum inhibitory concentrations ranging between 16 and 32 μg/mL. This is the first report of polyene antibiotics produced by Actinokineospora species as bioactive compounds against anthracnose fungi and pathogenic yeast strains.

  8. Active site mutations in yeast protein disulfide isomerase cause dithiothreitol sensitivity and a reduced rate of protein folding in the endoplasmic reticulum

    DEFF Research Database (Denmark)

    Holst, B; Tachibana, C; Winther, Jakob R.

    1997-01-01

    Aspects of protein disulfide isomerase (PDI) function have been studied in yeast in vivo. PDI contains two thioredoxin-like domains, a and a', each of which contains an active-site CXXC motif. The relative importance of the two domains was analyzed by rendering each one inactive by mutation to SGAS....... Such mutations had no significant effect on growth. The domains however, were not equivalent since the rate of folding of carboxypeptidase Y (CPY) in vivo was reduced by inactivation of the a domain but not the a' domain. To investigate the relevance of PDI redox potential, the G and H positions of each CGHC......-deleted strains overexpressing the yeast PDI homologue EUG1 are viable. Exchanging the wild-type Eug1p C(L/I)HS active site sequences for C(L/I)HC increased the growth rate significantly, however, further highlighting the importance of the oxidizing function for optimal growth....

  9. Antibacterial, antifungal and antioxidant activity of Olea africana against pathogenic yeast and nosocomial pathogens.

    Science.gov (United States)

    Masoko, Peter; Makgapeetja, David M

    2015-11-17

    Olea africana leaves are used by Bapedi people to treat different ailments. The use of these leaves is not validated, therefore the aim of this study is to validate antimicrobial properties of this plant. The ground leaves were extracted using solvents of varying polarity (hexane, chloroform, dichloromethane (DCM), ethyl acetate, acetone, ethanol, methanol, butanol and water). Thin layer chromatography (TLC) was used to analyse the chemical constituents of the extracts. The TLC plates were developed in three different solvent systems, namely, benzene/ethanol/ammonium solution (BEA), chloroform/ethyl acetate/formic acid (CEF) and ethyl acetate/methanol/water (EMW). The micro-dilution assay and bioautography method were used to evaluate the antibacterial activity of the extracts against Escherichia coli, Pseudomonas aeruginosa, Enterococcus faecalis and Staphylococcus aureus and the antifungal activity against Candida albicans and Cryptococcus neoformans. Methanol was the best extractant, yielding a larger amount of plant material whereas hexane yielded the least amount. In phytochemical analyses, more compounds were observed in BEA, followed by EMW and CEF. Qualitative 2, 2- diphenylpacryl-1-hydrazyl (DPPH) assay displayed that all the extracts had antioxidant activity. Antioxidant compounds could not be separated using BEA solvent system while with CEF and EMW enabled antioxidant compounds separation. The minimum inhibitory concentrations (MIC) values against test bacteria ranged between 0.16 and 2.50 mg/mL whereas against fungi, MIC ranged from 0.16 to 0.63 mg/mL. Bioautography results demonstrated that more than one compound was responsible for antimicrobial activity in the microdilution assay as the compounds were located at different Rf values. The results indicate that leaf extracts of Olea africana contain compounds with antioxidant, antibacterial and antifungal activities. Therefore, further studies are required to isolate the active compounds and perform

  10. Large-scale transcriptome data reveals transcriptional activity of fission yeast LTR retrotransposons

    DEFF Research Database (Denmark)

    Mourier, Tobias; Willerslev, Eske

    2010-01-01

    of transcriptional activity are observed from both strands of solitary LTR sequences. Transcriptome data collected during meiosis suggests that transcription of solitary LTRs is correlated with the transcription of nearby protein-coding genes. CONCLUSIONS: Presumably, the host organism negatively regulates...

  11. Antioxidant and Antibacterial Activity of the Beverage Obtained by Fermentation of Sweetened Lemon Balm (Melissa offi cinalis L.) Tea with Symbiotic Consortium of Bacteria and Yeasts

    OpenAIRE

    Dragoljub D. Cvetković; Siniša L. Markov; Vesna T. Tumbas Šaponjac; Jelena J. Vulić; Aleksandra S. Velićanski

    2014-01-01

    Kombucha is a fermented tea beverage which is traditionally prepared by fermenting sweetened black or green tea (Camellia sinensis L.) with symbiotic consortium of bacteria and yeasts (SCOBY). In this study, lemon balm (Melissa offi cinalis L.) was used as the only nitrogen source for kombucha fermentation. During the seven-day fermentation process, pH value, titratable acidity (TA), total phenolic content, phenolic compounds, and antioxidant activity against hydroxyl (˙OH) and 1,1-diphenyl-2...

  12. Yeast allosteric chorismate mutase is locked in the activated state by a single amino acid substitution

    International Nuclear Information System (INIS)

    Schmidheini, T.; Moesch, H.U.; Braus, G.; Evans, J.N.S.

    1990-01-01

    Chorismate mutase, a branch-point enzyme in the aromatic amino acid pathway of Saccharomyces cerevisiae, and also a mutant chorismate mutase with a single amino acid substitution in the C-terminal part of the protein have been purified approximately 20-fold and 64-fold from overproducing strains, respectively. The wild-type enzyme is activated by tryptophan and subject to feedback inhibition by tyrosine, whereas the mutant enzyme does not respond to activation by tryptophan nor inhibition by tyrosine. Both enzymes are dimers consisting of two identical subunits of M r 30,000, each one capable of binding one substrate and one activator molecule. Each subunit of the wild-type enzyme also binds one inhibitor molecule, whereas the mutant enzyme lost this ability. The enzyme reaction was observed by 1 H NMR and shows a direct and irreversible conversion of chorismate to prephenate without the accumulation of any enzyme-free intermediates. The kinetic data of the wild-type chorismate mutase show positive cooperativity toward the substrate with a Hill coefficient of 1.71 and a [S] 0.5 value of 4.0 mM. In the presence of the activator tryptophan, the cooperativity is lost. The enzyme has an [S] 0.5 value of 1.2 mM in the presence of 10 μM tryptophan and an increased [S] 0.5 value of 8.6 mM in the presence of 300 μM tyrosine. In the mutant enzyme, a loss of the cooperativity was observed, and [S] 0.5 was reduced to 1.0 mM. This enzyme is therefore locked in the activated state by a single amino acid substitution

  13. Dry reforming of methane with CO2 on an electron-activated iron catalytic bed.

    Science.gov (United States)

    Labrecque, Raynald; Lavoie, Jean-Michel

    2011-12-01

    A preliminary experimental investigation of dry reforming of methane with carbon dioxide, that has been performed on an iron bed activated with an electric current is reported. Operating conditions for the reaction included temperature ranging from 700 to 800° C and pressure close to 1 atm. The reaction, involving an excess of pure methane and carbon dioxide, was performed with and without addition of water vapour, provided by hot water saturation of the gaseous feed. According to syngas compositions, the electron flow has a dramatic effect on the conversion of both methane and carbon dioxide. It was shown also that hot water saturation of the CO(2) and CH(4) mixture allowed very good conversion, giving a syngas with a composition very close to what was expected from equilibrium calculations. Copyright © 2011 Elsevier Ltd. All rights reserved.

  14. Research of rheological characteristics and determination of rational parameters of drying process of activated ferment for bakery products

    Directory of Open Access Journals (Sweden)

    D. M. Borodulin

    2017-01-01

    Full Text Available The work is aimed at investigating the rheological properties of the ferment in the process of maturation and storage with subsequent determination of the rational parameters of its drying in various drying plants with the analysing of microflora of dried samples. We studied the rheological properties of the ferment using the strain of the lactobacilli L. Acidothilus 146A (activator and without it, which showed that the ferment for the production of special purpose bakery products to non-Newtonian or anomalously viscous liquids described by the Osthald-de-Vale rheological equation. We found that the introduction the strain of the lactobacilli L. Acidothilus 146A helps to reduce the viscosity during maturation by almost 3 times, and when storing the samples – in 2 times, this is indicated by the value of the consistency coefficient. The activator reduces the influence of temperature, so the structure of the ferment becomes more stable. It is easier to further process in this state. Consequently, the energy consumption for production is significantly reduced and the increases expiration date after the strain of the lactobacilli L. Acidothilus 146A is added to the starter for the production of special purpose bakery products. We detected kinetic patterns of drying of the activated ferment in thermoradiation, convective and sublimation dryers under different temperature operating conditions. We have determined the rational parameters of drying the ferment for the production of bakery products of specialized purpose. We analyzed the useful microflora of the dried samples. It has been revealed that microorganisms undergoing convective and sublimation (freeze drying are subjected to the smallest destructive effect. We found that microorganisms are less destroyed by convective and freeze drying. The microbial titer in these samples is at least 1(105CFU/g. While drying by the method of infrared irradiation, this titer is lower by a factor of ten

  15. Activation of the oxidative stress regulator PpYap1 through conserved cysteine residues during methanol metabolism in the yeast Pichia pastoris.

    Science.gov (United States)

    Yano, Taisuke; Yurimoto, Hiroya; Sakai, Yasuyoshi

    2009-06-01

    The methylotrophic yeast Pichia pastoris can grow on methanol as sole source of carbon and energy. The first reaction in yeast methanol metabolism, catalyzed by an abundant peroxisomal enzyme, alcohol oxidase, generates high levels of H(2)O(2), but the oxidative stress response during methanol metabolism has not been elucidated. In this study, we isolated the Yap1 homolog of P. pastoris (PpYap1) and analyzed the properties of a PpYAP1-disruption strain. The PpYap1 transcription factor is activated after exposure to various reactive agents, and therefore functions as a regulator of the redox system in P. pastoris. We have also identified PpGPX1, the unique glutathione peroxidase-encoding gene in P. pastoris whose expression is induced by PpYap1. PpGpx1, but not the ScTsa1 or SpTpx1 homolog PpTsa1, functions as a H(2)O(2) sensor and activates PpYap1. This study is the first demonstration of a yeast Yap1 family protein activated during conventional metabolism.

  16. Mek1 Down Regulates Rad51 Activity during Yeast Meiosis by Phosphorylation of Hed1.

    Science.gov (United States)

    Callender, Tracy L; Laureau, Raphaelle; Wan, Lihong; Chen, Xiangyu; Sandhu, Rima; Laljee, Saif; Zhou, Sai; Suhandynata, Ray T; Prugar, Evelyn; Gaines, William A; Kwon, YoungHo; Börner, G Valentin; Nicolas, Alain; Neiman, Aaron M; Hollingsworth, Nancy M

    2016-08-01

    During meiosis, programmed double strand breaks (DSBs) are repaired preferentially between homologs to generate crossovers that promote proper chromosome segregation at Meiosis I. In many organisms, there are two strand exchange proteins, Rad51 and the meiosis-specific Dmc1, required for interhomolog (IH) bias. This bias requires the presence, but not the strand exchange activity of Rad51, while Dmc1 is responsible for the bulk of meiotic recombination. How these activities are regulated is less well established. In dmc1Δ mutants, Rad51 is actively inhibited, thereby resulting in prophase arrest due to unrepaired DSBs triggering the meiotic recombination checkpoint. This inhibition is dependent upon the meiosis-specific kinase Mek1 and occurs through two different mechanisms that prevent complex formation with the Rad51 accessory factor Rad54: (i) phosphorylation of Rad54 by Mek1 and (ii) binding of Rad51 by the meiosis-specific protein Hed1. An open question has been why inhibition of Mek1 affects Hed1 repression of Rad51. This work shows that Hed1 is a direct substrate of Mek1. Phosphorylation of Hed1 at threonine 40 helps suppress Rad51 activity in dmc1Δ mutants by promoting Hed1 protein stability. Rad51-mediated recombination occurring in the absence of Hed1 phosphorylation results in a significant increase in non-exchange chromosomes despite wild-type levels of crossovers, confirming previous results indicating a defect in crossover assurance. We propose that Rad51 function in meiosis is regulated in part by the coordinated phosphorylation of Rad54 and Hed1 by Mek1.

  17. Mek1 Down Regulates Rad51 Activity during Yeast Meiosis by Phosphorylation of Hed1.

    Directory of Open Access Journals (Sweden)

    Tracy L Callender

    2016-08-01

    Full Text Available During meiosis, programmed double strand breaks (DSBs are repaired preferentially between homologs to generate crossovers that promote proper chromosome segregation at Meiosis I. In many organisms, there are two strand exchange proteins, Rad51 and the meiosis-specific Dmc1, required for interhomolog (IH bias. This bias requires the presence, but not the strand exchange activity of Rad51, while Dmc1 is responsible for the bulk of meiotic recombination. How these activities are regulated is less well established. In dmc1Δ mutants, Rad51 is actively inhibited, thereby resulting in prophase arrest due to unrepaired DSBs triggering the meiotic recombination checkpoint. This inhibition is dependent upon the meiosis-specific kinase Mek1 and occurs through two different mechanisms that prevent complex formation with the Rad51 accessory factor Rad54: (i phosphorylation of Rad54 by Mek1 and (ii binding of Rad51 by the meiosis-specific protein Hed1. An open question has been why inhibition of Mek1 affects Hed1 repression of Rad51. This work shows that Hed1 is a direct substrate of Mek1. Phosphorylation of Hed1 at threonine 40 helps suppress Rad51 activity in dmc1Δ mutants by promoting Hed1 protein stability. Rad51-mediated recombination occurring in the absence of Hed1 phosphorylation results in a significant increase in non-exchange chromosomes despite wild-type levels of crossovers, confirming previous results indicating a defect in crossover assurance. We propose that Rad51 function in meiosis is regulated in part by the coordinated phosphorylation of Rad54 and Hed1 by Mek1.

  18. Rhodotorula mucilaginosa, a quorum quenching yeast exhibiting lactonase activity isolated from a tropical shoreline.

    Science.gov (United States)

    Ghani, Norshazliza Ab; Sulaiman, Joanita; Ismail, Zahidah; Chan, Xin-Yue; Yin, Wai-Fong; Chan, Kok-Gan

    2014-04-09

    Two microbial isolates from a Malaysian shoreline were found to be capable of degrading N-acylhomoserine lactones. Both Matrix Assisted Laser Desorption Ionization-Time of Flight-Mass Spectrometry and 18S rDNA phylogenetic analyses confirmed that these isolates are Rhodotorula mucilaginosa. Quorum quenching activities were detected by a series of bioassays and rapid resolution liquid chromatography analysis. The isolates were able to degrade various quorum sensing molecules namely N-hexanoyl-L-homoserine lactone (C6-HSL), N-(3-oxo-hexanoyl)-L-homoserine lactone (3-oxo-C6-HSL) and N-(3-hydroxyhexanoyl)-L-homoserine lactone (3-hydroxy-C6-HSL). Using a relactonisation assay to verify the quorum quenching mechanism, it is confirmed that Rh. mucilaginosa degrades the quorum sensing molecules via lactonase activity. To the best of our knowledge, this is the first documentation of the fact that Rh. mucilaginosa has activity against a broad range of AHLs namely C6-HSL, 3-oxo-C6-HSL and 3-hydroxy-C6-HSL.

  19. Longevity of U cells of differentiated yeast colonies grown on respiratory medium depends on active glycolysis.

    Science.gov (United States)

    Čáp, Michal; Váchová, Libuše; Palková, Zdena

    2015-01-01

    Colonies of Saccharomyces cerevisiae laboratory strains pass through specific developmental phases when growing on solid respiratory medium. During entry into the so-called alkali phase, in which ammonia signaling is initiated, 2 prominent cell types are formed within the colonies: U cells in upper colony regions, which have a longevity phenotype and activate the expression of a large number of metabolic genes, and L cells in lower regions, which die more quickly and exhibit a starvation phenotype. Here, we performed a detailed analysis of the activities of enzymes of central carbon metabolism in lysates of both cell types and determined several fermentation end products, showing that previously reported expression differences are reflected in the different enzymatic capabilities of each cell type. Hence, U cells, despite being grown on respiratory medium, behave as fermenting cells, whereas L cells rely on respiratory metabolism and possess active gluconeogenesis. Using a spectrum of different inhibitors, we showed that glycolysis is essential for the formation, and particularly, the survival of U cells. We also showed that β-1,3-glucans that are released from the cell walls of L cells are the most likely source of carbohydrates for U cells.

  20. Temperature control strategy to enhance the activity of yeast inoculated into compost raw material for accelerated composting.

    Science.gov (United States)

    Nakasaki, Kiyohiko; Hirai, Hidehira

    2017-07-01

    The effects of inoculating the mesophilic yeast Pichia kudriavzevii RB1, which is able to degrade organic acids, on organic matter degradation in composting were elucidated. When model food waste with high carbohydrate content (C/N=22.3) was used, fluctuation in the inoculated yeast cell density was observed, as well as fluctuation in the composting temperature until day 5 when the temperature rose to 60°C, which is lethal for the yeast. After the decrease in yeast, acetic acid accumulated to levels as high as 20mg/g-ds in the composting material and vigorous organic matter degradation was inhibited. However, by maintaining the temperature at 40°C for 2days during the heating phase in the early stage of composting, both the organic acids originally contained in the raw material and acetic acid produced during the heating phase were degraded by the yeast. The concentration of acetic acid was kept at a relatively low level (10.1mg/g-ds at the highest), thereby promoting the degradation of organic matter by other microorganisms and accelerating the composting process. These results indicate that temperature control enhances the effects of microbial inoculation into composts. Copyright © 2017 Elsevier Ltd. All rights reserved.

  1. Endoplasmic reticulum involvement in yeast cell death

    International Nuclear Information System (INIS)

    Nicanor Austriaco, O.

    2012-01-01

    Yeast cells undergo programed cell death (PCD) with characteristic markers associated with apoptosis in mammalian cells including chromatin breakage, nuclear fragmentation, reactive oxygen species generation, and metacaspase activation. Though significant research has focused on mitochondrial involvement in this phenomenon, more recent work with both Saccharomyces cerevisiae and Schizosaccharomyces pombe has also implicated the endoplasmic reticulum (ER) in yeast PCD. This minireview provides an overview of ER stress-associated cell death (ER-SAD) in yeast. It begins with a description of ER structure and function in yeast before moving to a discussion of ER-SAD in both mammalian and yeast cells. Three examples of yeast cell death associated with the ER will be highlighted here including inositol starvation, lipid toxicity, and the inhibition of N-glycosylation. It closes by suggesting ways to further examine the involvement of the ER in yeast cell death.

  2. Phase modification induced drying shrinkage reduction on Na2CO3 activated slag by incorporating Na2SO4

    NARCIS (Netherlands)

    Yuan, B.; Yu, Q.; Brouwers, H.J.H.

    2017-01-01

    This paper aims to study the phase modification, reaction kinetics, mechanical properties and drying shrinkage of sodium carbonate activated slag by incorporating sodium sulfate in the activator. The results show that the reaction process is firstly controlled by CO32− anions, and later runs similar

  3. Interaction Between Yeasts and Zinc

    Science.gov (United States)

    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

  4. Timely activation of budding yeast APCCdh1 involves degradation of its inhibitor, Acm1, by an unconventional proteolytic mechanism.

    Directory of Open Access Journals (Sweden)

    Michael Melesse

    Full Text Available Regulated proteolysis mediated by the ubiquitin proteasome system is a fundamental and essential feature of the eukaryotic cell division cycle. Most proteins with cell cycle-regulated stability are targeted for degradation by one of two related ubiquitin ligases, the Skp1-cullin-F box protein (SCF complex or the anaphase-promoting complex (APC. Here we describe an unconventional cell cycle-regulated proteolytic mechanism that acts on the Acm1 protein, an inhibitor of the APC activator Cdh1 in budding yeast. Although Acm1 can be recognized as a substrate by the Cdc20-activated APC (APCCdc20 in anaphase, APCCdc20 is neither necessary nor sufficient for complete Acm1 degradation at the end of mitosis. An APC-independent, but 26S proteasome-dependent, mechanism is sufficient for complete Acm1 clearance from late mitotic and G1 cells. Surprisingly, this mechanism appears distinct from the canonical ubiquitin targeting pathway, exhibiting several features of ubiquitin-independent proteasomal degradation. For example, Acm1 degradation in G1 requires neither lysine residues in Acm1 nor assembly of polyubiquitin chains. Acm1 was stabilized though by conditional inactivation of the ubiquitin activating enzyme Uba1, implying some requirement for the ubiquitin pathway, either direct or indirect. We identified an amino terminal predicted disordered region in Acm1 that contributes to its proteolysis in G1. Although ubiquitin-independent proteasome substrates have been described, Acm1 appears unique in that its sensitivity to this mechanism is strictly cell cycle-regulated via cyclin-dependent kinase (Cdk phosphorylation. As a result, Acm1 expression is limited to the cell cycle window in which Cdk is active. We provide evidence that failure to eliminate Acm1 impairs activation of APCCdh1 at mitotic exit, justifying its strict regulation by cell cycle-dependent transcription and proteolytic mechanisms. Importantly, our results reveal that strict cell

  5. Timely Activation of Budding Yeast APCCdh1 Involves Degradation of Its Inhibitor, Acm1, by an Unconventional Proteolytic Mechanism

    Science.gov (United States)

    Melesse, Michael; Choi, Eunyoung; Hall, Hana; Walsh, Michael J.; Geer, M. Ariel; Hall, Mark C.

    2014-01-01

    Regulated proteolysis mediated by the ubiquitin proteasome system is a fundamental and essential feature of the eukaryotic cell division cycle. Most proteins with cell cycle-regulated stability are targeted for degradation by one of two related ubiquitin ligases, the Skp1-cullin-F box protein (SCF) complex or the anaphase-promoting complex (APC). Here we describe an unconventional cell cycle-regulated proteolytic mechanism that acts on the Acm1 protein, an inhibitor of the APC activator Cdh1 in budding yeast. Although Acm1 can be recognized as a substrate by the Cdc20-activated APC (APCCdc20) in anaphase, APCCdc20 is neither necessary nor sufficient for complete Acm1 degradation at the end of mitosis. An APC-independent, but 26S proteasome-dependent, mechanism is sufficient for complete Acm1 clearance from late mitotic and G1 cells. Surprisingly, this mechanism appears distinct from the canonical ubiquitin targeting pathway, exhibiting several features of ubiquitin-independent proteasomal degradation. For example, Acm1 degradation in G1 requires neither lysine residues in Acm1 nor assembly of polyubiquitin chains. Acm1 was stabilized though by conditional inactivation of the ubiquitin activating enzyme Uba1, implying some requirement for the ubiquitin pathway, either direct or indirect. We identified an amino terminal predicted disordered region in Acm1 that contributes to its proteolysis in G1. Although ubiquitin-independent proteasome substrates have been described, Acm1 appears unique in that its sensitivity to this mechanism is strictly cell cycle-regulated via cyclin-dependent kinase (Cdk) phosphorylation. As a result, Acm1 expression is limited to the cell cycle window in which Cdk is active. We provide evidence that failure to eliminate Acm1 impairs activation of APCCdh1 at mitotic exit, justifying its strict regulation by cell cycle-dependent transcription and proteolytic mechanisms. Importantly, our results reveal that strict cell-cycle expression profiles

  6. Dried extracts of Encholirium spectabile (Bromeliaceae) present antioxidant and photoprotective activities in vitro

    Science.gov (United States)

    de Oliveira, Raimundo Gonçalves; Souza, Grasielly Rocha; Guimarães, Amanda Leite; de Oliveira, Ana Paula; Silva Morais, Amanda Caroline; da Cruz Araújo, Edigênia Cavalcante; Nunes, Xirley Pereira; Almeida, Jackson Roberto Guedes da Silva

    2013-01-01

    The antioxidant and photoprotective activities of dried extracts from the leaves of Encholirium spectabile were investigated. It was also evaluated the total phenolic and flavonoid contents by the Folin–Ciocalteu and aluminum chloride methods, respectively. Antioxidant activities of the extracts were evaluated by using of 2,2-diphenyl-1-picrylhydrazil (DPPH) radical scavenging and β-carotene–linoleic acid bleaching and compared with ascorbic acid, butylated hydroxyanisole (BHA) and butylated hydroxytoluene (BHT) used as reference compounds. The photoprotective effect was evaluated by the spectrophotometric method. The most significant total phenolic and flavonoid contents was of 188.50 ± 27.50 mg of gallic acid equivalent/g and 129.70 ± 4.59 mg of catechin equivalent/g, respectively, for chloroform fraction (Es-CHCl3). The Es-CHCl3 also presented the best antioxidant activity (IC50 25.35 ± 4.35 μg/ml) for DPPH scavenging. The ethanol extract (Es-EtOH), Es-CHCl3 and the fraction ethyl acetate (Es-AcOEt) showed characteristic absorption bands in regions UVB and UVA in a concentration-dependent manner. Es-CHCl3 presented the highest sun protection factor SPF (8.89 ± 2.11). It shows the possibility to use this extract as sunscreen in pharmaceutical preparations. PMID:24396251

  7. Genetically engineered yeast

    DEFF Research Database (Denmark)

    2014-01-01

    A genetically modified Saccharomyces cerevisiae comprising an active fermentation pathway producing 3-HP expresses an exogenous gene expressing the aminotransferase YhxA from Bacillus cereus AH1272 catalysing a transamination reaction between beta-alanine and pyruvate to produce malonate semialde......A genetically modified Saccharomyces cerevisiae comprising an active fermentation pathway producing 3-HP expresses an exogenous gene expressing the aminotransferase YhxA from Bacillus cereus AH1272 catalysing a transamination reaction between beta-alanine and pyruvate to produce malonate...... semialdehyde. The yeast may also express a 3-hydroxyisobutyrate dehydrogenase (HIBADH) and a 3-hydroxypropanoate dehydrogenase (3-HPDH) and aspartate 1-decarboxylase. Additionally the yeast may express pyruvate carboxylase and aspartate aminotransferase....

  8. Requirement of the propeptide for in vivo formation of active yeast carboxypeptidase Y

    DEFF Research Database (Denmark)

    Ramos, C; Winther, Jakob R.; Kielland-Brandt, Morten

    1994-01-01

    Deletions have been constructed in the region encoding the 91-amino acid propeptide of the vacuolar enzyme carboxypeptidase Y of Saccharomyces cerevisiae, and in vivo effects of these mutations on the intracellular transport of the mutant proenzymes have been examined. Deletions did not include...... the vacuolar targeting signal, and none of the mutated forms of procarboxypeptidase Y was found to be secreted. All deletions, however, resulted in a decreased rate of transport of the truncated proenzymes from the endoplasmic reticulum to the Golgi apparatus. Up to 29 residues close to the N terminus can...... be removed without completely eliminating transport of the mutated proenzymes to the vacuole. However, the C-terminal part of the propeptide contains elements which are essential, since two small deletions, of 9 and 15 residues, respectively, within this area resulted in loss of carboxypeptidase Y activity...

  9. Activity of Salvia dolomitica and Salvia somalensis Essential Oils against Bacteria, Molds and Yeasts

    Directory of Open Access Journals (Sweden)

    Valentina Virginia Ebani

    2018-02-01

    Full Text Available Essential oils (EOs from Salvia dolomitica and Salvia somalensis, widely employed in the cosmetic and perfume industry, were analyzed for composition and tested against bacterial and fungal pathogens isolated from clinical and environmental specimens. The analyses were carried out against Staphylococcus aureus, Staphylococcus pseudointermedius, Pseudomonas aeruginosa, Escherichia coli, Streptococcus canis, Streptococcus pyogenes, Klebsiella pneumoniae, Proteus mirabilis, Microsporum canis, Microsporum gypseum, Trichophyton mentagrophytes, Aspergillus niger, Aspergillus flavus, Candida albicans, Candida krusei, Mucor sp. and Trichothecium roseum. Both EOs showed similar percentages of total monoterpenes and sesquiterpene hydrocarbons. The main constituents were 1,8-cineole and β-caryophyllene in S. dolomitica and bornyl acetate and camphor in S. somalensis. The selected EOs have no relevant antifungal or antibacterial activities if compared to conventional drugs.

  10. Participation of SRM5/CDC28, SRM8/NET1 and SRM12/HF11 genes in activation of checkpoints of Yeast Saccharomyces Cerevisiae

    International Nuclear Information System (INIS)

    Kadyshevskaya, E.Yu.; Koltovaya, N.A.

    2007-01-01

    It is known that there are about twenty checkpoint genes in yeast Saccharomyces cerevisiae. We study participation of SRM genes selected as genes affecting genetic stability and radiosensitivity. It has been shown that srm5/cdc28-srm, srm8/net1-srm, srm12/hfil-srm mutations prevent checkpoint activation by DNA damage, particularly G0/S-checkpoint (srm5, srm8), G1/S-checkpoint (srm5, srm8, srm12), S-checkpoint (srm5, srm12) and G2-checkpoint (srm5). These data indicate, at least in budding yeast, CDC28/SRM5, HF11/ADA1/SRM12 and NET1/SRM8 genes mediate cellular response induced by DNA damage including checkpoint control

  11. Studies on microbiological treatment and utilization of cane molasses distillery wastes. Part 1. Screening of useful yeast strains

    Energy Technology Data Exchange (ETDEWEB)

    Akaki, M.; Takahashi, T.; Ishiguro, K.

    1981-01-01

    Cane molasses distillation slops were used as substrate for the cultivation of 203 strains of yeast. Most yeast strains, especially Hansenula, Debaryomyces, and Rhodotorula, assimilated the molasses distillation wastes. Yeast cell dry weight reached 0.9 grams/100 mL, and yeasts removed greater than 30% of the COD of the waste material.

  12. Fungi treated with small chemicals exhibit increased antimicrobial activity against facultative bacterial and yeast pathogens.

    Science.gov (United States)

    Zutz, Christoph; Bandian, Dragana; Neumayer, Bernhard; Speringer, Franz; Gorfer, Markus; Wagner, Martin; Strauss, Joseph; Rychli, Kathrin

    2014-01-01

    For decades, fungi have been the main source for the discovery of novel antimicrobial drugs. Recent sequencing efforts revealed a still high number of so far unknown "cryptic" secondary metabolites. The production of these metabolites is presumably epigenetically silenced under standard laboratory conditions. In this study, we investigated the effect of six small mass chemicals, of which some are known to act as epigenetic modulators, on the production of antimicrobial compounds in 54 spore forming fungi. The antimicrobial effect of fungal samples was tested against clinically facultative pathogens and multiresistant clinical isolates. In total, 30 samples of treated fungi belonging to six different genera reduced significantly growth of different test organisms compared to the untreated fungal sample (growth log reduction 0.3-4.3). For instance, the pellet of Penicillium restrictum grown in the presence of butyrate revealed significant higher antimicrobial activity against Staphylococcus (S.) aureus and multiresistant S. aureus strains and displayed no cytotoxicity against human cells, thus making it an ideal candidate for antimicrobial compound discovery. Our study shows that every presumable fungus, even well described fungi, has the potential to produce novel antimicrobial compounds and that our approach is capable of rapidly filling the pipeline for yet undiscovered antimicrobial substances.

  13. Curing Ingredients, Characteristics, Total Phenolic, and Antioxidant Activity of Commercial Indonesian Dried Meat Product (Dendeng

    Directory of Open Access Journals (Sweden)

    T. Suryati

    2012-08-01

    Full Text Available Dendeng is Indonesian dried meat product that used spices rich in antioxidant component as ingredient. In addition, commercial dendeng usually use saltpeter (nitrate/nitrite salt as curing ingredient to inhibit rancidity and to produce stable red color. The aims of this study were to investigate composition of spices and saltpeter added, characteristic, total phenolic, and antioxidant activity of commercial dendeng. This research was conducted through interview with some dendeng producers to get information about saltpeter adding and spices composition used in their products. Then the interview results were verified by laboratory analysis. The results showed that spices and saltpeter adding from some producers varied. The saltpeter added in curing process produced inconsistent red color on commercial dendeng in this investigation. Total phenolic of dendeng from producers ranged from 42.47 to 102.0 mg GAE/100 g DM for raw dendeng, and 36.51 to 95.49 mg GAE/100 g DM for fried dendeng. Antioxidant capacity against DPPH ranged from 79.35 to 379.40 mg VCE/100 g DM for raw dendeng, and 94.30 to 559.40 mg VCE/100 g DM for fried dendeng. Antioxidant capacity of raw dendeng was influenced by phenolic content about 87.2%, but in fried dendeng was only 59.0%. In conclusion, dendeng has a significant antioxidant activity, even after frying, and saltpeter addition was not effective to maintain stable red color in dendeng products.

  14. Geneva cocktail for cytochrome p450 and P-glycoprotein activity assessment using dried blood spots.

    Science.gov (United States)

    Bosilkovska, M; Samer, C F; Déglon, J; Rebsamen, M; Staub, C; Dayer, P; Walder, B; Desmeules, J A; Daali, Y

    2014-09-01

    The suitability of the capillary dried blood spot (DBS) sampling method was assessed for simultaneous phenotyping of cytochrome P450 (CYP) enzymes and P-glycoprotein (P-gp) using a cocktail approach. Ten volunteers received an oral cocktail capsule containing low doses of the probes bupropion (CYP2B6), flurbiprofen (CYP2C9), omeprazole (CYP2C19), dextromethorphan (CYP2D6), midazolam (CYP3A), and fexofenadine (P-gp) with coffee/Coke (CYP1A2) on four occasions. They received the cocktail alone (session 1), and with the CYP inhibitors fluvoxamine and voriconazole (session 2) and quinidine (session 3). In session 4, subjects received the cocktail after a 7-day pretreatment with the inducer rifampicin. The concentrations of probes/metabolites were determined in DBS and plasma using a single liquid chromatography-tandem mass spectrometry method. The pharmacokinetic profiles of the drugs were comparable in DBS and plasma. Important modulation of CYP and P-gp activities was observed in the presence of inhibitors and the inducer. Minimally invasive one- and three-point (at 2, 3, and 6 h) DBS-sampling methods were found to reliably reflect CYP and P-gp activities at each session.

  15. Effect of drying methods with the application of vacuum microwaves on the bioactive compounds, color, and antioxidant activity of strawberry fruits.

    Science.gov (United States)

    Wojdyło, Aneta; Figiel, Adam; Oszmiański, Jan

    2009-02-25

    The objective of this study was to evaluate the application of vacuum-microwave drying (240, 360, and 480 W) in the production process of dehydrated strawberry and to compare and contrast the quality of these dehydrated strawberries in terms of their polyphenol compounds, concentration of some heat liable components, and color to that of freeze-dried, convective, and vacuum-dried strawberry. Thus, the effect of vacuum-microwave drying and other drying methods on the antioxidant activity of berries was evaluated. Whole fresh and dried fruits were assessed for phenolics (anthocyanins, flavanols, hydroxycinnamic acids, and flavonols), ascorbic acid, and antioxidant activity (all parameters were calculated on a dry matter basis). Analysis of data shows that ellagic acid and flavanol changes were affected by drying techniques and cultivar. Drying destroyed anthocyanins, flavanols, and ascorbic acid, and there was a significant decrease in antioxidant activity. The most striking result was that conventional and vacuum drying decreased antioxidant activity in both cultivars, whereas contradictory results were found for vacuum-microwave processed strawberry. This study has demonstrated that vacuum-microwave drying, especially at 240 W, can produce high-quality products, with the additional advantage of reduced processing times, compared to other processes such as freeze-drying.

  16. Antioxidant Enzyme Activity and Meat Quality of Meat Type Ducks Fed with Dried Oregano ( L. Powder

    Directory of Open Access Journals (Sweden)

    J. H. Park

    2015-01-01

    Full Text Available One-day-old Cherry valley meat-strain ducks were used to investigate the effect of supplemental dried oregano powder (DOP in feed on the productivity, antioxidant enzyme activity, and breast meat quality. One hundred sixty five ducks were assigned to 5 dietary treatments for 42 days. The dietary treatment groups were control group (CON; no antibiotic, no DOP, antibiotic group (ANT; CON+0.1% Patrol, 0.1% DOP (CON+0.1% DOP, 0.5% DOP (CON+0.5% DOP, and 1.0% DOP (CON+1.0% DOP. Upon feeding, 1,1-diphenyl-2-picryl-hydrazyl (DPPH radical scavenging activity of oregano extracts was higher than that of tocopherol, although it was less than that of ascorbic acid. As a result of in vivo study, DOP in the diet showed no effects on final body weight, feed intake, or feed conversion ratio. However, dietary 0.5% and 1% DOP supplementation caused a significant increase in the serum enzyme activity of superoxide dismutase (SOD compared with CON and ANT, while glutathione peroxidase (GPx in tissue was increased as compared to ANT (p<0.05. Cooking loss from ducks fed with DOP decreased compared with the control ducks. Thiobarbituric acid reactive substance (TBARS values of duck breast meat at 5 d post slaughter was found to be significantly reduced in ducks whose diets were supplemented with 0.5% and 1% DOP (p<0.05. These results suggest that diets containing 0.5% and 1% DOP may beneficially affect antioxidant enzyme activity of GPx and SOD, improve meat cooking loss, and reduce TBARS values in breast meat at 5 d of storage in ducks.

  17. Effect of yeast biomass with high content of carotenoids on erythrocyte deformability, NO production and Na,K-ATPase activity in healthy and LPS treated rats.

    Science.gov (United States)

    Radosinska, J; Mezesova, L; Okruhlicova, L; Frimmel, K; Breierova, E; Bartekova, M; Vrbjar, N

    2016-11-25

    Measurements of red blood cell (RBC) deformability together with estimation of NO-synthase activity and Na,K-ATPase activity were used for characterization of RBC functionality in rats subjected to single dose of Escherichia coli lipopolysaccharides (LPS) at a dose of 1 mg/kg. We hypothesized that LPS might initiate a malfunction of RBC. We also investigated the potential effect of carotenoids (10 mg/kg/day) produced in red yeast biomass of Rhodotorula glutinis on RBC in LPS-challenged rats. LPS significantly reduced the deformability of RBC (by 14%) together with decrease of NO-synthase activity by 20%. Daily supplementation of carotenoids for 10 days attenuated the LPS-induced injury, as observed by 22% increase of RBC deformability and 23% increase of NO-synthase activity. The activity of Na,K-ATPase was also improved probably due to increased number of active enzyme molecules as indicated by 66% enhancement of Vmax value, hence maintaining the activity of erythrocyte Na,K-ATPase to the level even higher as compared with healthy control animals. It may be concluded that administration of yeast biomass with high content of carotenoids resulted in advanced function of erythrocytes as concerns their ability to squeeze through narrow capillaries of the circulation, better intrinsic production of NO and improvement of intracellular homeostasis of sodium.

  18. Enhancement of the proline and nitric oxide synthetic pathway improves fermentation ability under multiple baking-associated stress conditions in industrial baker's yeast

    Directory of Open Access Journals (Sweden)

    Sasano Yu

    2012-04-01

    Full Text Available Abstract Background During the bread-making process, industrial baker's yeast, mostly Saccharomyces cerevisiae, is exposed to baking-associated stresses, such as air-drying and freeze-thaw stress. These baking-associated stresses exert severe injury to yeast cells, mainly due to the generation of reactive oxygen species (ROS, leading to cell death and reduced fermentation ability. Thus, there is a great need for a baker's yeast strain with higher tolerance to baking-associated stresses. Recently, we revealed a novel antioxidative mechanism in a laboratory yeast strain that is involved in stress-induced nitric oxide (NO synthesis from proline via proline oxidase Put1 and N-acetyltransferase Mpr1. We also found that expression of the proline-feedback inhibition-less sensitive mutant γ-glutamyl kinase (Pro1-I150T and the thermostable mutant Mpr1-F65L resulted in an enhanced fermentation ability of baker's yeast in bread dough after freeze-thaw stress and air-drying stress, respectively. However, baker's yeast strains with high fermentation ability under multiple baking-associated stresses have not yet been developed. Results We constructed a self-cloned diploid baker's yeast strain with enhanced proline and NO synthesis by expressing Pro1-I150T and Mpr1-F65L in the presence of functional Put1. The engineered strain increased the intracellular NO level in response to air-drying stress, and the strain was tolerant not only to oxidative stress but also to both air-drying and freeze-thaw stresses probably due to the reduced intracellular ROS level. We also showed that the resultant strain retained higher leavening activity in bread dough after air-drying and freeze-thaw stress than that of the wild-type strain. On the other hand, enhanced stress tolerance and fermentation ability did not occur in the put1-deficient strain. This result suggests that NO is synthesized in baker's yeast from proline in response to oxidative stresses that induce ROS

  19. Enhancement of the proline and nitric oxide synthetic pathway improves fermentation ability under multiple baking-associated stress conditions in industrial baker's yeast.

    Science.gov (United States)

    Sasano, Yu; Haitani, Yutaka; Hashida, Keisuke; Ohtsu, Iwao; Shima, Jun; Takagi, Hiroshi

    2012-04-01

    During the bread-making process, industrial baker's yeast, mostly Saccharomyces cerevisiae, is exposed to baking-associated stresses, such as air-drying and freeze-thaw stress. These baking-associated stresses exert severe injury to yeast cells, mainly due to the generation of reactive oxygen species (ROS), leading to cell death and reduced fermentation ability. Thus, there is a great need for a baker's yeast strain with higher tolerance to baking-associated stresses. Recently, we revealed a novel antioxidative mechanism in a laboratory yeast strain that is involved in stress-induced nitric oxide (NO) synthesis from proline via proline oxidase Put1 and N-acetyltransferase Mpr1. We also found that expression of the proline-feedback inhibition-less sensitive mutant γ-glutamyl kinase (Pro1-I150T) and the thermostable mutant Mpr1-F65L resulted in an enhanced fermentation ability of baker's yeast in bread dough after freeze-thaw stress and air-drying stress, respectively. However, baker's yeast strains with high fermentation ability under multiple baking-associated stresses have not yet been developed. We constructed a self-cloned diploid baker's yeast strain with enhanced proline and NO synthesis by expressing Pro1-I150T and Mpr1-F65L in the presence of functional Put1. The engineered strain increased the intracellular NO level in response to air-drying stress, and the strain was tolerant not only to oxidative stress but also to both air-drying and freeze-thaw stresses probably due to the reduced intracellular ROS level. We also showed that the resultant strain retained higher leavening activity in bread dough after air-drying and freeze-thaw stress than that of the wild-type strain. On the other hand, enhanced stress tolerance and fermentation ability did not occur in the put1-deficient strain. This result suggests that NO is synthesized in baker's yeast from proline in response to oxidative stresses that induce ROS generation and that increased NO plays an important

  20. Enhancement of the proline and nitric oxide synthetic pathway improves fermentation ability under multiple baking-associated stress conditions in industrial baker's yeast

    Science.gov (United States)

    2012-01-01

    Background During the bread-making process, industrial baker's yeast, mostly Saccharomyces cerevisiae, is exposed to baking-associated stresses, such as air-drying and freeze-thaw stress. These baking-associated stresses exert severe injury to yeast cells, mainly due to the generation of reactive oxygen species (ROS), leading to cell death and reduced fermentation ability. Thus, there is a great need for a baker's yeast strain with higher tolerance to baking-associated stresses. Recently, we revealed a novel antioxidative mechanism in a laboratory yeast strain that is involved in stress-induced nitric oxide (NO) synthesis from proline via proline oxidase Put1 and N-acetyltransferase Mpr1. We also found that expression of the proline-feedback inhibition-less sensitive mutant γ-glutamyl kinase (Pro1-I150T) and the thermostable mutant Mpr1-F65L resulted in an enhanced fermentation ability of baker's yeast in bread dough after freeze-thaw stress and air-drying stress, respectively. However, baker's yeast strains with high fermentation ability under multiple baking-associated stresses have not yet been developed. Results We constructed a self-cloned diploid baker's yeast strain with enhanced proline and NO synthesis by expressing Pro1-I150T and Mpr1-F65L in the presence of functional Put1. The engineered strain increased the intracellular NO level in response to air-drying stress, and the strain was tolerant not only to oxidative stress but also to both air-drying and freeze-thaw stresses probably due to the reduced intracellular ROS level. We also showed that the resultant strain retained higher leavening activity in bread dough after air-drying and freeze-thaw stress than that of the wild-type strain. On the other hand, enhanced stress tolerance and fermentation ability did not occur in the put1-deficient strain. This result suggests that NO is synthesized in baker's yeast from proline in response to oxidative stresses that induce ROS generation and that increased NO

  1. An evolvable oestrogen receptor activity sensor: development of a modular system for integrating multiple genes into the yeast genome

    NARCIS (Netherlands)

    Fox, J.E.; Bridgham, J.T.; Bovee, T.F.H.; Thornton, J.W.

    2007-01-01

    To study a gene interaction network, we developed a gene-targeting strategy that allows efficient and stable genomic integration of multiple genetic constructs at distinct target loci in the yeast genome. This gene-targeting strategy uses a modular plasmid with a recyclable selectable marker and a

  2. The Effect of Drying Conditions on the Antidiabetic Activity of the ...

    African Journals Online (AJOL)

    Ethanolic extracts of the leaves of Vernonia amygdalina were obtained by maceration from the freshly -harvested leaves, leaves dried in the shade, and leaves dried at 40 °C in the hot air oven. Solvent removal was achieved with the aid of a rotary evaporator. White albino rats of both sexes weighing 90-145 g were used.

  3. Data in support of antioxidant activities of the non-extractable fraction of dried persimmon (Diospyros kaki Thunb.

    Directory of Open Access Journals (Sweden)

    Yoko Matsumura

    2016-09-01

    Full Text Available This data article is related to the research article entitled, “Antioxidant potential in non-extractable fraction of dried persimmon (Diospyros kaki Thunb.” (Matsumura et al., 2016 [1]. We investigated antioxidant activities of the non-extractable fraction of dried persimmon fruits in vitro and in vivo. We evaluated both extracted fraction and non-extractable fraction, and reported that non-extractable fraction may possess significantly antioxidant potential in vivo on the basis of the oxygen radical absorbance capacity (ORAC. We showed our experimental raw data about antioxidant capacity of dried persimmon, plasma triglycerides (TG and HDL-cholesterol (HDL-C, and this data article might contribute to evaluate real antioxidant capacity of other fruits and vegetables. Keywords: Persimmon, Antioxidant activity, Oxygen radical absorbance capacity (ORAC, Model of the gastrointestinal tract

  4. The Influence of Different Drying Methods on Constituents and Antioxidant Activity of Saffron from China

    Directory of Open Access Journals (Sweden)

    Yingpeng Tong

    2015-01-01

    Full Text Available More and more saffron has been cultivated in China because of the increasing saffron demand, but no paper has studied the influence of drying methods on the quality of Chinese saffron. In this paper, three different dehydration treatments applied in actual production were evaluated: dehydration with electric oven, vacuum oven, and microwave. We determined that the highest quality of saffron will be obtained when fresh saffron is treated at higher temperatures (no more than 70°C for a long time by electric oven drying and vacuum oven drying. In microwave drying, treatments at lower microwave power and longer time benefit the quality of saffron. In addition, the influence of the drying method on antioxidants in saffron is discussed. The correlation between individual saffron profiles and the antioxidant value was estimated by spectrum-effect relationships analysis.

  5. Effect of Infrared Blanching on Enzyme Activity and Retention of β-Carotene and Vitamin C in Dried Mango.

    Science.gov (United States)

    Guiamba, Isabel R F; Svanberg, Ulf; Ahrné, Lilia

    2015-06-01

    The objectives of this work were to evaluate infrared (IR) dry blanching in comparison with conventional water blanching prior to hot air drying of mango to inactivate polyphenol oxidase (PPO) and ascorbic acid oxidase (AAO) enzymes, and to study its effect on color change and retention of vitamin C and β-carotene. Mango cylinders were blanched under similar temperature-time conditions either by IR heating or by immersion in a water bath during 2 min at 90 °C (high-temperature-short-time-HTST) or for 10 min at 65 °C (low-temperature-long-time-LTLT). After blanching mango was hot air dried at 70 °C. PPO was completely inactivated during the blanching treatments, but AAO had a moderate remaining activity after LTLT treatment (∼30%) and a low remaining activity after HTST treatment (9% to 15%). A higher retention of vitamin C was observed in mango subjected to IR dry blanching, 88.3 ± 1.0% (HTST) and 69.2 ± 2.9% (LTLT), compared with water blanching, 61.4 ± 5.3% (HTST) and 50.7 ± 9.6% (LTLT). All-trans-β-carotene retention was significantly higher in water blanched dried mango, 93.2 ± 5.2% (LTLT) and 91.4 ± 5.1% (HTST), compared with IR dry blanched, 73.6 ± 3.6% (LTLT) and 76.9 ± 2.9% (HTST). Increased levels of 13-cis-β-carotene isomer were detected only in IR dry blanched mango, and the corresponding dried mango also had a slightly darker color. IR blanching of mango prior to drying can improve the retention of vitamin C, but not the retention of carotenoids, which showed to be more dependent on the temperature than the blanching process. A reduction of drying time was observed in LTLT IR-blanching mango. © 2015 Institute of Food Technologists®

  6. Diversity of yeasts involved in the fermentation of tchoukoutou, an opaque sorghum beer from Benin

    OpenAIRE

    Kayode, A.P.P.; Vieira-Dalode, G.; Linnemann, A.R.; Kotchoni, S.O.; Hounhouigan, A.J.D.; Boekel, van, M.A.J.S.; Nout, M.J.R.

    2011-01-01

    Opaque sorghum beers are traditional alcoholic beverages in several African countries. Known as tchoukoutou in Benin, the beer is often obtained from an uncontrolled fermentation. It is consumed in an actively fermenting state and has a sour taste. The present study characterized and identified the yeasts involved in the fermentation process of this type of beer using the phenotypical approach. Of 12 beers from 4 different locations, the mean values of the pH, titratable acidity, dry matter c...

  7. Performance evaluation of startup for a yeast membrane bioreactor (MBRy) treating landfill leachate.

    Science.gov (United States)

    Amaral, Míriam C S; Gomes, Rosimeire F; Brasil, Yara L; Oliveira, Sílvia M A; Moravia, Wagner G

    2017-12-06

    The startup process of a membrane bioreactor inoculated with yeast biomass (Saccharomyces cerevisiae) and used in the treatment of landfill leachate was evaluated. The yeast membrane bioreactor (MBRy) was inoculated with an exogenous inoculum, a granulated active dry commercial bakers' yeast. The MBRy was successfully started up with a progressive increase in the landfill leachate percentage in the MBRy feed and the use of Sabouraud Dextrose Broth. The membrane plays an important role in the startup phase because of its full biomass retention and removal of organic matter. MBRy is a suitable and promising process to treat recalcitrant landfill leachate. After the acclimation period, the COD and NH 3 removal efficiency reached values of 72 ± 3% and 39 ± 2% respectively. MBRy shows a low membrane-fouling potential. The membrane fouling was influenced by soluble microbial products, extracellular polymeric substances, sludge particle size, and colloidal dissolved organic carbon.

  8. Vibro-fluidized bed heat pump drying of mint leaves with respect to phenolic content, antioxidant activity, and color indices

    Directory of Open Access Journals (Sweden)

    Ataei Ardestani Seyed Majid

    2015-01-01

    Full Text Available Because of high porosity and stickiness of mint leaves, they could not be fluidized well during fluidization. In this study, a vibro-fluidized bed dryer assisted heat pump system was designed and fabricated to overcome this problem. The drying experiments were carried out at temperatures of 40, 50 and 60 °C. The quality of the dehydrated samples was assessed based on color indices, antioxidant activity, and total phenolic content. Drying process primarily occurred in falling rate period. The effective coefficient of moisture transfer of the samples was increased with air temperature and varied from 4.26656×10-11 to 2.95872×10-10 m2 s-1 for heat pump drying (HPD method, and 3.71918×10-11 to 1.29196×10-10 m2 s-1 for none-heat pump drying (NHPD method. The color indices for temperatures of 40 and 50 °C were very close to each other, whereas by increasing temperature to 60 °C, a remarkable loss of green color was observed. The highest phenolic content was found in methanolic extract for HPD at 60 °C, and NHPD at 50 °C contained the lowest amount of phenolic compounds. NHPD treatments showed lower antioxidant activity compared to HPD treatments at the same temperature due to the longer drying times.

  9. The development and implementation of a dry active waste (DAW) sorting program at Catawba Nuclear Station

    International Nuclear Information System (INIS)

    Schulte, J.H.; McNamara, P.N.

    1988-01-01

    Duke Power Company, like other nuclear utilities, bears a burdensome radwaste disposal cost that has rapidly escalated during recent years. Dry active waste (DAW) represents approximately 85% of the total radioactive waste volume shipped to low-level disposal facilities. Sorting waste with less than detectable radioactivity from waste with detectable radioactivity provides a volume reduction (VR) technique that can save significant radwaste disposal costs and conserve dwindling burial space. This paper presents the development and results of a project that was conducted at Catawba Nuclear Station to determine the volume reduction potential from sorting DAW. Guidelines are given so that other utilities can perform a VR potential study on a low cost basis. Based on the results of the DAW VR study, an overall DAW volume radiation program was initiated at Duke Power Company. This program includes personnel training, drumming techniques, bag tracking and equipment purchases for sorting. This program has been fully implemented at Duke Power Company since January 1, 1988 and preliminary results and savings are given

  10. Below Regulatory Concern Owners Group: An evaluation of dry active waste sorting: Final report

    International Nuclear Information System (INIS)

    Casey, S.M.

    1989-02-01

    The objective of this research was to determine the accuracy of manual inspection of Dry Active Waste (DAW). Three studies were conducted at two nuclear power plants in which unmodified DAW waste streams of roughly 10,000 items each were inspected by technicians using pancake probes. Sorting performance was measured unobtrusively by intercepting the ''outflow'' from inspection stations. Verification of sorting accuracy was performed with a prototype, semi-automated sorting table employing a matrix of fixed plastic scintillation detectors. More than 30,000 items of trash were examined, classified, counted, and verified, and the composition of the ''inflow'' to the inspection stations was determined by reconstructing the ''outflow'' components, as determined during verification procedures. The results showed that between 1 and 19% of all items in each of the three DAW waste streams were contaminated at levels ≥100 ccpm. Sixty-two percent of the ''contaminated'' items in Study I, 87% of the contaminated items in Study II, and 97% of the contaminated items in Study III were detected. One-half to one percent of all items classified as <100 ccpm by technicians were actually ≥100 ccpm. False positive rates were very high in all three studies. The production rates and accuracy obtained on the semi-automated plastic scintillation sorting table used during the verification stages of this project greatly exceeded the rates for manual sorting. 9 figs., 13 tabs

  11. Fatty acids from oleaginous yeasts and yeast-like fungi and their potential applications.

    Science.gov (United States)

    Xue, Si-Jia; Chi, Zhe; Zhang, Yu; Li, Yan-Feng; Liu, Guang-Lei; Jiang, Hong; Hu, Zhong; Chi, Zhen-Ming

    2018-02-01

    Oleaginous yeasts, fatty acids biosynthesis and regulation in the oleaginous yeasts and the fatty acids from the oleaginous yeasts and their applications are reviewed in this article. Oleaginous yeasts such as Rhodosporidium toruloides, Yarrowia lipolytica, Rhodotorula mucilaginosa, and Aureobasidium melanogenum, which can accumulate over 50% lipid of their cell dry weight, have many advantages over other oleaginous microorganisms. The fatty acids from the oleaginous yeasts have many potential applications. Many oleaginous yeasts have now been genetically modified to over-produce fatty acids and their derivatives. The most important features of the oleaginous yeasts are that they have special enzymatic systems for enhanced biosynthesis and regulation of fatty acids in their lipid particles. Recently, some oleaginous yeasts such as R. toruloides have been found to have a unique fatty acids synthetase and other oleaginous yeasts such as A. melanogenum have a unique highly reducing polyketide synthase (HR-PKS) involved in the biosynthesis of hydroxyl fatty acids. It is necessary to further enhance lipid biosynthesis using metabolic engineering and explore new applications of fatty acids in biotechnology.

  12. Low-activity spectrometric gamma-ray logging technique for delineation of coal/rock interfaces in dry blast holes

    International Nuclear Information System (INIS)

    Asfahani, J.; Borsaru, M.

    2007-01-01

    A low-activity spectrometric gamma-ray logging technique is proposed in this paper as a sensitive tool for the delineation of coal/rock interfaces in dry blast holes. The advantages and superiority of this technique over traditional micro-density non-spectrometric gamma-ray tools are demonstrated

  13. Vicilin-like peptides from Capsicum baccatum L. seeds are α-amylase inhibitors and exhibit antifungal activity against important yeasts in medical mycology.

    Science.gov (United States)

    Vieira Bard, Gabriela C; Nascimento, Viviane V; Oliveira, Antônia Elenir A; Rodrigues, Rosana; Da Cunha, Maura; Dias, Germana B; Vasconcelos, Ilka M; Carvalho, Andre O; Gomes, Valdirene M

    2014-07-01

    The objective of this study was to isolate antimicrobial peptides from Capsicum baccatum seeds and evaluate their antimicrobial activity and inhibitory effects against α-amylase. Initially, proteins from the flour of C. baccatum seeds were extracted in sodium phosphate buffer, pH 5.4, and precipitated with ammonium sulfate at 90% saturation. The D1 and D2 fractions were subjected to antifungal tests against the yeasts Saccharomyces cerevisiae, Candida albicans, Candida tropicalis, and Kluyveromyces marxiannus, and tested against α-amylases from Callosobruchus maculates and human saliva. The D2 fraction presented higher antimicrobial activity and was subjected to further purification and seven new different fractions (H1-H7) were obtained. Peptides in the H4 fraction were sequenced and the N-terminal sequences revealed homology with previously reported storage vicilins from seeds. The H4 fraction exhibited strong antifungal activity and also promoted morphological changes in yeast, including pseudohyphae formation. All fractions, including H4, inhibited mammalian α-amylase activity but only the H4 fraction was able to inhibit C. maculatus α-amylase activity. These results suggest that the fractions isolated from the seeds of C. baccatum can act directly in plant defenses against pathogens and insects. © 2014 Wiley Periodicals, Inc.

  14. Spray-dried powders improve the controlled release of antifungal tioconazole-loaded polymeric nanocapsules compared to with lyophilized products

    International Nuclear Information System (INIS)

    Ribeiro, Roseane Fagundes; Motta, Mariana Heldt; Härter, Andréia Pisching Garcia; Flores, Fernanda Cramer; Beck, Ruy Carlos Ruver; Schaffazick, Scheila Rezende

    2016-01-01

    This work aimed to obtain solid formulations from polymeric nanocapsules and nanoemulsions containing tioconazole, a broad spectrum antifungal drug. Two dehydration methods were used: spray-drying and freeze-drying, using lactose as adjuvant (10%, w/v). The liquid formulations had a mean particle size around 206 nm and 182 nm for nanocapsules and nanoemulsions, respectively, and an adequate polydispersity index. Tioconazole content was close to the theoretical amount (1.0 mg/mL). After drying, the content ranged between 98 and 102% with a mean nanometric size of the dried products after redispersion. Scanning electron microscopy showed that the particles are rounded, sphere-shaped for the dried products obtained by spray-drying, and shapeless and irregular shapes for those obtained by freeze-drying. In the microbiological evaluation, all dried products remained active against the yeast Candida albicans when compared to the original systems. The dried products obtained by spray-drying from nanocapsules presented better control of the tioconazole release when compared to the freeze-drying products. - Highlights: • Polymeric nanocapsule suspensions containing tioconazole were submitted to spray-drying and freeze-drying. • Dried products from nanocapsule suspensions were stable for 30 days. • Release studies showed that the dried products presented greater control of drug release compared to the original suspension.

  15. Spray-dried powders improve the controlled release of antifungal tioconazole-loaded polymeric nanocapsules compared to with lyophilized products

    Energy Technology Data Exchange (ETDEWEB)

    Ribeiro, Roseane Fagundes [Programa de Pós-Graduação em Ciências Farmacêuticas, Universidade Federal de Santa Maria, Av. Roraima, 1000, Santa Maria, RS, 97105-900 (Brazil); Motta, Mariana Heldt [Curso de Farmácia, Centro de Ciências da Saúde, Universidade Federal de Santa Maria, Av. Roraima, 1000, Santa Maria, RS, 97105-900 (Brazil); Härter, Andréia Pisching Garcia; Flores, Fernanda Cramer [Programa de Pós-Graduação em Ciências Farmacêuticas, Universidade Federal de Santa Maria, Av. Roraima, 1000, Santa Maria, RS, 97105-900 (Brazil); Beck, Ruy Carlos Ruver [Programa de Pós-Graduação em Ciências Farmacêuticas, Faculdade de Farmácia, Universidade Federal do Rio Grande do Sul, Av. Ipiranga, 2752, Porto Alegre, RS, 90610-000 (Brazil); Schaffazick, Scheila Rezende [Programa de Pós-Graduação em Ciências Farmacêuticas, Universidade Federal de Santa Maria, Av. Roraima, 1000, Santa Maria, RS, 97105-900 (Brazil); and others

    2016-02-01

    This work aimed to obtain solid formulations from polymeric nanocapsules and nanoemulsions containing tioconazole, a broad spectrum antifungal drug. Two dehydration methods were used: spray-drying and freeze-drying, using lactose as adjuvant (10%, w/v). The liquid formulations had a mean particle size around 206 nm and 182 nm for nanocapsules and nanoemulsions, respectively, and an adequate polydispersity index. Tioconazole content was close to the theoretical amount (1.0 mg/mL). After drying, the content ranged between 98 and 102% with a mean nanometric size of the dried products after redispersion. Scanning electron microscopy showed that the particles are rounded, sphere-shaped for the dried products obtained by spray-drying, and shapeless and irregular shapes for those obtained by freeze-drying. In the microbiological evaluation, all dried products remained active against the yeast Candida albicans when compared to the original systems. The dried products obtained by spray-drying from nanocapsules presented better control of the tioconazole release when compared to the freeze-drying products. - Highlights: • Polymeric nanocapsule suspensions containing tioconazole were submitted to spray-drying and freeze-drying. • Dried products from nanocapsule suspensions were stable for 30 days. • Release studies showed that the dried products presented greater control of drug release compared to the original suspension.

  16. Abnormal activity of corneal cold thermoreceptors underlies the unpleasant sensations in dry eye disease.

    Science.gov (United States)

    Kovács, Illés; Luna, Carolina; Quirce, Susana; Mizerska, Kamila; Callejo, Gerard; Riestra, Ana; Fernández-Sánchez, Laura; Meseguer, Victor M; Cuenca, Nicolás; Merayo-Lloves, Jesús; Acosta, M Carmen; Gasull, Xavier; Belmonte, Carlos; Gallar, Juana

    2016-02-01

    Dry eye disease (DED) affects >10% of the population worldwide, and it provokes an unpleasant sensation of ocular dryness, whose underlying neural mechanisms remain unknown. Removal of the main lachrymal gland in guinea pigs caused long-term reduction of basal tearing accompanied by changes in the architecture and density of subbasal corneal nerves and epithelial terminals. After 4 weeks, ongoing impulse activity and responses to cooling of corneal cold thermoreceptor endings were enhanced. Menthol (200 μM) first excited and then inactivated this augmented spontaneous and cold-evoked activity. Comparatively, corneal polymodal nociceptors of tear-deficient eyes remained silent and exhibited only a mild sensitization to acidic stimulation, whereas mechanonociceptors were not affected. Dryness-induced changes in peripheral cold thermoreceptor responsiveness developed in parallel with a progressive excitability enhancement of corneal cold trigeminal ganglion neurons, primarily due to an increase of sodium currents and a decrease of potassium currents. In corneal polymodal nociceptor neurons, sodium currents were enhanced whereas potassium currents remain unaltered. In healthy humans, exposure of the eye surface to menthol vapors or to cold air currents evoked unpleasant sensations accompanied by increased blinking frequency that we attributed to cold thermoreceptor stimulation. Notably, stimulation with menthol reduced the ongoing background discomfort of patients with DED, conceivably due to use-dependent inactivation of cold thermoreceptors. Together, these data indicate that cold thermoreceptors contribute importantly to the detection and signaling of ocular surface wetness, and develop under chronic eye dryness conditions an injury-evoked neuropathic firing that seems to underlie the unpleasant sensations experienced by patients with DED.

  17. Prions in yeast

    OpenAIRE

    Bezdíčka, Martin

    2013-01-01

    The thesis describes yeast prions and their biological effects on yeast in general. It defines the basic characteristics of yeast prions, that distinguish prions from other proteins. The thesis introduces various possibilities of prion formation, and propagation as well as specific types of yeast prions, including various functions of most studied types of prions. The thesis also focuses on chaperones that affect the state of yeast prions in cells. Lastly, the thesis indicates similarities be...

  18. Novel insight into neutrophil immune responses by dry mass determination of Candida albicans morphotypes.

    Directory of Open Access Journals (Sweden)

    Ava Hosseinzadeh

    Full Text Available The common fungal pathogen Candida albicans has the ability to grow as a yeast or as a hypha and can alternate between these morphotypes. The overall biomass of both morphotypes increases with growth. However, only yeasts, but not hyphae, exist as discrete cellular entities. Multiplicity of infection (MOI is a useful parameter to determine the initial inoculum of yeasts for in vitro infection assays. Since the amount of hyphae is difficult to quantify, comparable starting conditions in such assays cannot be determined accurately for yeasts and hyphae using MOI. To circumvent this problem, we have established a set of correlation coefficients to convert fungal metabolic activity and optical density to dry mass. Using these correlations, we were able to accurately compare ROS production and IL-8 release by polymorphonuclear neutrophils upon infection with equal dry mass amounts of yeast and hyphal morphotypes. Neutrophil responses depended on the initial form of infection, irrespective of C. albicans wild-type yeasts transforming to hyphal growth during the assay. Infection with a high mass of live C. albicans yeasts resulted in lower neutrophil ROS and this decrease stems from efficient ROS detoxification by C. albicans without directly affecting the phagocyte ROS machinery. Moreover, we show that dead C. albicans induces significantly less ROS and IL-8 release than live fungi, but thimerosal-killed C. albicans were still able to detoxify neutrophil ROS. Thus, the dry mass approach presented in this study reveals neutrophil responses to different amounts and morphotypes of C. albicans and serves as a template for studies that aim to identify morphotype-specific responses in a variety of immune cells.

  19. Revaluation of Waste Yeast from Beer Production

    Directory of Open Access Journals (Sweden)

    Nicoleta Suruceanu

    2013-11-01

    Full Text Available Brewing yeast is an important waste product from beer production. The valorification of slurry yeast mainly consists of separation of vitamins and important nitrogen compounds. The hops compounds, one of the most important raw materials in beer technology are removed beforehand valorification. The prenylflavonoids compounds from hops are important bioactive compounds that can be revaluation with proper technology. Revaluation of prenylflavonoids from waste yeast into dietary supplement, identification and quantification of xanthohumol by HPLC method. Waste yeast from brewery pilot plant of USAMV Cluj Napoca it was dried by atomization and the powder was analyzed on xanthohumol content by HPLC method. For quantification a calibration curve it was used. The process of drying by atomisation lead to a powder product. It was used malt dextrin powder for stabilisation. The final product it was encapsulated. The xanthohumol content of powdered yeast it was 1.94 µg/ml. In conclusion the slurry yeast from beer production it is an important source of prenylflavonoids compounds.

  20. Color formation in nitrite-free dried hams as related to Zn-protoporphyrin IX and Zn-chelatase activity.

    Science.gov (United States)

    Parolari, Giovanni; Benedini, Riccardo; Toscani, Tania

    2009-08-01

    The development of red pigment Zn-protoporphyrin IX (ZPP) in nitrite-free Parma hams was investigated in 5 leg muscles at several stages of processing and the activity of muscle Zn-chelatase was concurrently assayed for its potential role in ZPP formation. A steady increase of the pigment was observed throughout the manufacturing stages at mild temperatures while no development was observed during the prior cold resting phase. The enzyme was partly inactivated according to a muscle-dependent pattern, resulting in similar ZPP contents, hence color, in finished hams. It is concluded that enzyme-dependent synthesis of ZPP in nitrite-free dried hams contributes to color development, enabling muscles in dried hams to become more similar in redness than in green thighs. Therefore, checking raw meat for the enzyme content may be a means to control color formation in nitrite-free dry-cured meat derivatives.

  1. PHYTOCHEMICAL PROFILE AND INSECTICIDAL ACTIVITY OF ESSENTIAL OIL FROM FRESH AND DRIED LEAVES OF NIGERIAN GROWN Citrus meyerii

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    Lamidi Ajao Usman

    2016-07-01

    Full Text Available Leaves of Citrus meyerii harvested fresh and dried for four consecutive days were separately hydro-distilled and yielded 0.11 – 0.24 %(w/w of essential oils. Characterisation of the oils using Gas chromatography - mass spectrometry (GC-MS revealed the predominance of hydrocarbon monoterpenoids 51.1 – 68.3%. Oxygenated monoterpenoids, hydrocarbon sesquiterpenoids and oxygenated sesquiterpenoids constituted (17.4 - 24.9%, (12.2 - 19.8% and (0.0 – 2.5% of the oils respectively. Principal constituents of the oils were; 3-carene (10.1-30.7%, α-pinene (1.0%-18.7%, d-limonene (5.2-6.4%, cis-β-ocimene (5.8-14.2%, citronellal (5.4-6.8%, and β-elemene (3.0-5.8%. The oils were of 3-carene and α-pinene chemotypes. Oils that were of 3-carene chemotype were those from fresh and the leaves dried for one and four days while the oils from leaves dried for two and three days were of α-pinene chemotype.  Insecticidal activities of the oils were determined using contact toxicity test on Callosobruchus maculatus. Regardless of whether the leaves were fresh or dried, the oils were active against the insect. Interestingly, there was no significant difference in the activities of the oils against the insect.

  2. Mathematical modeling of microwave dried celery leaves and determination of the effective moisture diffusivities and activation energy

    Directory of Open Access Journals (Sweden)

    Ilknur Alibas

    2014-06-01

    Full Text Available Celery (Apium graveolens L. var. secalinum Alef leaves with 50±0.07 g weight and 91.75±0.15% humidity (~11.21 db were dried using 8 different microwave power densities ranging between 1.8-20 W g-1, until the humidity fell down to 8.95±0.23% (~0.1 db. Microwave drying processes were completed between 5.5 and 77 min depending on the microwave power densities. In this study, measured values were compared with predicted values obtained from twenty thin layer drying theoretical, semi-empirical and empirical equations with a new thin layer drying equation. Within applied microwave power density; models whose coefficient and correlation (R² values are highest were chosen as the best models. Weibull distribution model gave the most suitable predictions at all power density. At increasing microwave power densities, the effective moisture diffusivity values ranged from 1.595 10-10 to 6.377 10-12 m2 s-1. The activation energy was calculated using an exponential expression based on Arrhenius equation. The linear relationship between the drying rate constant and effective moisture diffusivity gave the best fit.

  3. Multi trace element analysis of dry biological materials by neutron activation analysis including a chemical group separation

    International Nuclear Information System (INIS)

    Weers, C.A.

    1980-07-01

    Multi-element analysis of dry biological material by neutron activation analysis has to include radiochemical separation. The evaporation process is described in terms of the half-volume. The pretreatment of the samples and the development of the destruction-evaporation apparatus are described. The successive adsorption steps with active charcoal, Al 2 O 3 and coprecipitation with Fe(OH) 3 are described. Results obtained for standard reference materials are summarized. (G.T.H.)

  4. Desempenho de Poedeiras Comerciais Alimentadas com Levedura Seca (Saccharomyces Crevisiae de Cana-de-Açúcar Performance of Commercial Brown Egg Layers Fed Dried Yeast (Saccharomyces Cerevisiae of Sugar-Cane

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    GAR Maia

    2001-05-01

    Full Text Available Essa pesquisa teve por objetivo avaliar o efeito da adição de levedura seca de álcool (LSA à dieta de poedeiras. Foram utilizadas 120 poedeiras Isabrown com 33 semanas de idade, distribuídas em um delineamento estatístico de blocos ao acaso, com cinco tratamentos (0, 7, 14, 21 e 28% de levedura, quatro repetições e seis aves por unidade experimental. Rações isoprotéicas (18% PB, isoenergéticas (2.800 kcal EM/kg, isocálcicas (3,8% Ca e isofosfóricas (0,38% Pd foram formuladas à base de milho e farelo de soja. Os níveis de LSA não afetaram a produção galinha dia (PGD=94,71± 0,96%, peso dos ovos (PO=64,35± 0,85g, peso médio final das aves (PMF=1.872,07± 50,36g, ganho de peso das aves (GP=-52± 25,84g e umidade das excretas (UE=75,85± 3,81%. Observou-se efeito quadrático para as variáveis: consumo de ração (CR=117,03-0,34LSA+0,02LSA² e conversão alimentar por dúzia de ovos (CADO=1,48-0,0025LSA+0,00023LSA². Efeito linear foi observado para a variável conversão alimentar por massa de ovo (CAMO=1,867+0,0072LSA. A utilização de até 14% de levedura proporcionou desempenho semelhante ao obtido com a dieta à base de milho e farelo de soja. A análise econômica mostrou ser viável a utilização de níveis até 28% de levedura.This research had the objective of evaluating the effect of growing levels of dry yeast of alcohol (LSA to the laying hen diet. One hundred and twenty Isabrown laying hens were used with 33 weeks of age, in a randomized complete block design, with five treatments, four replicates and six birds per pen. The diets (18% CP, 2800 kcal ME/kg, 3,8% Ca and 0,38% AP, were formulated based on corn and soybean meal, with five levels of LSA inclusion: 0; 7; 14; 21 and 28,0%. The levels of LSA did not affect the production of hen per day (PGD=94,71± 0,96%, egg weight (PO=64,35± 0,85g, chicken weight (PMF=1.872,07± 50,36g, weight gain (GP=-52± 25,84g, and moisture of faeces (UE=75,85± 3,81%. Quadratic

  5. Effects of a yeast-dried milk product in creep and phase-1 nursery diets on growth performance, circulating immunoglobulin A, and fecal microbiota of nursing and nursery pigs.

    Science.gov (United States)

    Tran, H; Bundy, J W; Hinkle, E E; Walter, J; Burkey, T E; Miller, P S

    2014-10-01

    Four experiments were conducted to evaluate effects of yeast-dried milk (YDM) product in creep and phase-1 nursery diets. In Exp. 1, 24 parity-4 litters were allotted to 3 dietary treatments (8 litters/treatment) including no creep (NC), control creep (CTL), and experimental creep (EC; 10% YDM). Creep diets were fed twice daily from d 7 after birth until weaning (23.6 ± 1.8 d). In Exp. 2, 108 weaned pigs were selected based on mean BW of pigs from the respective treatments in Exp. 1. For phase 1 (d 0 to 7 postweaning) of Exp. 2, NC and CTL pigs were fed the CTL diet and EC pigs continued to receive the EC diet. For phase 2 and 3 (d 7 to 28 postweaning) of Exp. 2, all pigs received a common diet containing antibiotics. Blood and fecal samples were collected on d 0, 7, 14, and 21 postweaning to evaluate serum IgA and fecal microbiota. In Exp. 1, pigs fed EC and CTL tended to have greater (P < 0.10) weaning BW compared with NC pigs. Pigs fed EC had greater (P < 0.05) ADFI compared with CTL pigs. In Exp. 2, pigs fed EC tended to have greater BW (P < 0.10) and greater ADG (P < 0.05) and ADFI (P < 0.01) compared with CTL and NC pigs (d 0 to 28). For serum IgA, EC and CTL pigs tended (P < 0.10) to have greater IgA compared with NC pigs. For microbial data, EC pigs had greater (P < 0.01) microbial diversity compared with CTL (d 7 postweaning). On d 7 and 21 postweaning, microbial similarity decreased (P < 0.01) in pigs fed EC compared with NC and CTL. Overall (d 0 to 14), lactobacilli gene copy numbers tended (P < 0.10) to be greater in EC (7.3 log10) compared with NC pigs (6.9 log10). In Exp. 3, 23 parity-1 litters were allotted to 3 dietary treatments as described for Exp. 1. In Exp. 4, 108 weaned pigs were selected based on mean BW of all pigs from Exp. 3 and dietary treatments were the same as described for Exp. 2 except no antibiotic was included in phase-2 diet. In Exp. 3, there were no treatment effects on litter ADFI, ADG, and serum IgA, but a tendency (P < 0

  6. Quantitative characteristics of carcass and meat quality of ¾ Boer + ¼ Saanen and Saanen goat kids fed diets with dry yeast Características quantitativas de carcaça e de qualidade da carne de cabritos ¾ Boer + ¼ Saanen e Saanen alimentados com rações contendo levedura seca

    Directory of Open Access Journals (Sweden)

    Hanna Sakamoto Freitas

    2011-03-01

    Full Text Available Twenty-seven carcasses of non-castrated confined goat kids, (18 ¾ Boer + ¼ Saanen and nine Saanen with slaughtered weight of 30.1 ± 0.27 kg were used to evaluate quantitative characteristics of the carcass and qualitative characteristics of the loin and shoulder. The animals were distributed in a completely randomized design in a 2 × 3 factorial arrangement (breed group × diet. The diets consisted of inclusion of dry yeast, as follows: soybean meal, soybean meal + dried yeast or dried yeast. The other ingredients of the diets were oat hay (30% DM, ground corn and mineral mixture. Hot carcass weight, cold carcass weight, weight loss by cooling, true carcass yield and carcass compactness index were not influenced by the inclusion of dry yeast nor by racial group. Saanen goats presented the highest carcass commercial yield of carcass, but they needed 15 days more to reach the slaughter weight. The cut yields were not affected, but a significant interaction for shoulder yield occurred. Dry yeast and breed group did not influence the measurements of the loin, the muscle:bone ratio, the cooking losses, the shear force and composition. There was a significant interaction between the inclusion of dry yeast in the diets and the breed group for the muscle proportion on loin, which was higher in the ¾ Boer + ¼ Saanen group. For the shoulder, inclusion of dry yeast and breed group did not alter the proportions of muscle, fat, protein and ash. However, in Saanen goats, the proportion of bone and moisture content were higher and total lipid content was lower. The ¾ Boer + ¼ Saanen groups showed higher precocity. Dry yeast is an alternative protein source that can be included in diets for goat kids.Foram utilizadas 27 carcaças de cabritos machos não-castrados, confinados, sendo 18 ¾ Boer + ¼ Saanen e nove Saanen com peso de abate de 30,1 ± 0,27 kg, para avaliar as características quantitativas da carcaça e qualitativas do lombo e da paleta. Os

  7. The IRC7 gene encodes cysteine desulphydrase activity and confers on yeast the ability to grow on cysteine as a nitrogen source.

    Science.gov (United States)

    Santiago, Margarita; Gardner, Richard C

    2015-07-01

    Although cysteine desulphydrase activity has been purified and characterized from Saccharomyces cerevisiae, the gene encoding this activity in vivo has never been defined. We show that the full-length IRC7 gene, encoded by the YFR055W open reading frame, encodes a protein with cysteine desulphydrase activity. Irc7p purified to homogeneity is able to utilize l-cysteine as a substrate, producing pyruvate and hydrogen sulphide as products of the reaction. Purified Irc7p also utilized l-cystine and some other cysteine conjugates, but not l-cystathionine or l-methionine, as substrates. We further show that, in vivo, the IRC7 gene is both necessary and sufficient for yeast to grow on l-cysteine as a nitrogen source, and that overexpression of the gene results in increased H2 S production. Strains overexpressing IRC7 are also hypersensitive to a toxic analogue, S-ethyl-l-cysteine. While IRC7 has been identified as playing a critical role in converting cysteine conjugates to volatile thiols that are important in wine aroma, its biological role in yeast cells is likely to involve regulation of cysteine and redox homeostasis. Copyright © 2015 John Wiley & Sons, Ltd.

  8. The sandfly Lutzomyia longipalpis LL5 embryonic cell line has active Toll and Imd pathways and shows immune responses to bacteria, yeast and Leishmania.

    Science.gov (United States)

    Tinoco-Nunes, Bruno; Telleria, Erich Loza; da Silva-Neves, Monique; Marques, Christiane; Azevedo-Brito, Daisy Aline; Pitaluga, André Nóbrega; Traub-Csekö, Yara Maria

    2016-04-20

    Lutzomyia longipalpis is the main vector of visceral leishmaniasis in Latin America. Sandfly immune responses are poorly understood. In previous work we showed that these vector insects respond to bacterial infections by modulating a defensin gene expression and activate the Imd pathway in response to Leishmania infection. Aspects of innate immune pathways in insects (including mosquito vectors of human diseases) have been revealed by studying insect cell lines, and we have previously demonstrated antiviral responses in the L. longipalpis embryonic cell line LL5. The expression patterns of antimicrobial peptides (AMPs) and transcription factors were evaluated after silencing the repressors of the Toll pathway (cactus) and Imd pathway (caspar). AMPs and transcription factor expression patterns were also evaluated after challenge with heat-killed bacteria, heat-killed yeast, or live Leishmania. These studies showed that LL5 cells have active Toll and Imd pathways, since they displayed an increased expression of AMP genes following silencing of the repressors cactus and caspar, respectively. These pathways were also activated by challenges with bacteria, yeast and Leishmania infantum chagasi. We demonstrated that L. longipalpis LL5 embryonic cells respond to immune stimuli and are therefore a good model to study the immunological pathways of this important vector of leishmaniasis.

  9. Porosity and water activity effects on stability of crystalline β-carotene in freeze-dried solids.

    Science.gov (United States)

    Harnkarnsujarit, Nathdanai; Charoenrein, Sanguansri; Roos, Yrjö H

    2012-11-01

    Stability of entrapped crystalline β-carotene as affected by water activity, solids microstructure, and composition of freeze-dried systems was investigated. Aliquots (1000 mm(3) , 20% w/w solids) of solutions of maltodextrins of various dextrose equivalents (M040:DE6, M100:DE11, and M250:DE25.5), M100-sugars (1:1 glucose, fructose and sucrose), and agar for gelation with dispersed β-carotene were frozen at -20, -40, or -80 °C and freeze-dried. Glass transition and α-relaxation temperatures were determined with differential scanning calorimetry and dynamic mechanical analysis, respectively. β-Carotene contents were monitored spectrophotometrically. In the glassy solids, pore microstructure had a major effect on β-carotene stability. Small pores with thin walls and large surface area allowed β-carotene exposure to oxygen which led to a higher loss, whereas structural collapse enhanced stability of β-carotene by decreasing exposure to oxygen. As water plasticized matrices, an increase in molecular mobility in the matrix enhanced β-carotene degradation. Stability of dispersed β-carotene was highest at around 0.2 a(w) , but decreasing structural relaxation times above the glass transition correlated well with the rate of β-carotene degradation at higher a(w) . Microstructure, a(w) , and component mobility are important factors in the control of stability of β-carotene in freeze-dried solids. β-Carotene expresses various nutritional benefits; however, it is sensitive to oxygen and the degradation contributes to loss of nutritional values as well as product color. To increase stability of β-carotene in freeze-dried foods, the amount of oxygen penetration need to be limited. The modification of freeze-dried food structures, for example, porosity and structural collapse, components, and humidity effectively enhance the stability of dispersed β-carotene in freeze-dried solids. © 2012 Institute of Food Technologists®

  10. Effect of starter cultures combinations on lipolytic activity and ripening of dry fermented sausages

    Directory of Open Access Journals (Sweden)

    Enver Baris Bingol

    2014-11-01

    Full Text Available The effect of starter culture combinations on the quality of Turkish type dry fermented sausage (sucuk were evaluated during ripening and storage periods. Sucuk formulations were produced without (control and with three different starter culture combinations; i Staphylococcus carnosus+Pediococcus pentosaceus, ii Staphylococcus carnosus+ Lactobacillus sakei, and iii Staphylococcus carnosus+Pediococcus pentosaceus+Lactobacillus sakei. Analysis of microbiological, physico-chemical and lipase enzyme levels of samples were conducted until the 60th day. Interactions among the presence of lipolytic starter cultures, lipase enzyme levels and thiobarbituric acid reactive substances were also evaluated both in ripening and drying periods. There were apparent differences on microbiological and chemical properties between samples prepared with starters and control. It has been concluded that the use of lipolytic starter cultures in suitable combination would have positive effect on the acceleration of ripening and improvement of the quality of dry fermented sausages.

  11. Natural draught centralized dry store for irradiated fuel and active waste

    International Nuclear Information System (INIS)

    Bradley, N.; Brown, G.A.

    1981-01-01

    A modular design is described for the long term dry storage of irradiated fuel and vitrified fission products. The specification set by the Central Electricity Generating Board for the AGR fuel store was that the store should be capable of accommodating the lifetime discharge from 10 AGR reactors (7200 tonnes of irradiated fuel) and be cooled by natural convection. The fuel assemblies should be enclosed in individual steel containers. The store has an area for drying the AGR fuel and containering. The single dry cell storage capacities are, 5 years output from 1300 MWe station stored as fuel elements, or 14 year output from 1300 MWe thermal reactors stored as vitrified fission products. (U.K.)

  12. Assessment of Antioxidant Activity of Spray Dried Extracts of Psidium guajava Leaves by DPPH and Chemiluminescence Inhibition in Human Neutrophils

    Directory of Open Access Journals (Sweden)

    M. R. V. Fernandes

    2014-01-01

    Full Text Available This work evaluated the physicochemical properties and antioxidant activity of spray dried extracts (SDE from Psidium guajava L. leaves. Different drying carriers, namely, maltodextrin, colloidal silicon dioxide, Arabic gum, and β-cyclodextrin at concentrations of 40 and 80% relative to solids content, were added to drying composition. SDE were characterized through determination of the total phenolic, tannins, and flavonoid content. Antioxidant potential of the SDE was assessed by two assays: cellular test that measures the luminol-enhanced chemiluminescence (LumCL produced by neutrophils stimulated with phorbol myristate acetate (PMA and the DPPH radical scavenging (DPPH* method. In both assays the antioxidant activity of the SDE occurred in a concentration-dependent manner and showed no toxicity to the cells. Using the CLlum method, the IC50 ranged from 5.42 to 6.50 µg/mL. The IC50 of the SDE ranged from 7.96 to 8.11 µg/mL using the DPPH• method. Psidium guajava SDE presented significant antioxidant activity; thus they show high potential as an active phytopharmaceutical ingredient. Our findings in human neutrophils are pharmacologically relevant since they indicate that P. guajava SDE is a potential antioxidant and anti-inflammatory agent in human cells.

  13. Assessment of antioxidant activity of spray dried extracts of Psidium guajava leaves by DPPH and chemiluminescence inhibition in human neutrophils.

    Science.gov (United States)

    Fernandes, M R V; Azzolini, A E C S; Martinez, M L L; Souza, C R F; Lucisano-Valim, Y M; Oliveira, W P

    2014-01-01

    This work evaluated the physicochemical properties and antioxidant activity of spray dried extracts (SDE) from Psidium guajava L. leaves. Different drying carriers, namely, maltodextrin, colloidal silicon dioxide, Arabic gum, and β -cyclodextrin at concentrations of 40 and 80% relative to solids content, were added to drying composition. SDE were characterized through determination of the total phenolic, tannins, and flavonoid content. Antioxidant potential of the SDE was assessed by two assays: cellular test that measures the luminol-enhanced chemiluminescence (LumCL) produced by neutrophils stimulated with phorbol myristate acetate (PMA) and the DPPH radical scavenging (DPPH∗ method). In both assays the antioxidant activity of the SDE occurred in a concentration-dependent manner and showed no toxicity to the cells. Using the CLlum method, the IC50 ranged from 5.42 to 6.50 µg/mL. The IC50 of the SDE ranged from 7.96 to 8.11 µg/mL using the DPPH(•) method. Psidium guajava SDE presented significant antioxidant activity; thus they show high potential as an active phytopharmaceutical ingredient. Our findings in human neutrophils are pharmacologically relevant since they indicate that P. guajava SDE is a potential antioxidant and anti-inflammatory agent in human cells.

  14. The effect of increased yeast alcohol acetyltransferase and esterase activity on the flavour profiles of wine and distillates.

    Science.gov (United States)

    Lilly, Mariska; Bauer, Florian F; Lambrechts, Marius G; Swiegers, Jan H; Cozzolino, Daniel; Pretorius, Isak S

    2006-07-15

    The fruity odours of wine are largely derived from the synthesis of esters and higher alcohols during yeast fermentation. The ATF1- and ATF2-encoded alcohol acetyltransferases of S. cerevisiae are responsible for the synthesis of ethyl acetate and isoamyl acetate esters, while the EHT1-encoded ethanol hexanoyl transferase is responsible for synthesizing ethyl caproate. However, esters such as these might be degraded by the IAH1-encoded esterase. The objectives of this study were: (a) to overexpress the genes encoding ester-synthesizing and ester-degrading enzymes in wine yeast; (b) to prepare Colombard table wines and base wines for distillation using these modified strains; and (c) to analyse and compare the ester concentrations and aroma profiles of these wines and distillates. The overexpression of ATF1 significantly increased the concentrations of ethyl acetate, isoamyl acetate, 2-phenylethyl acetate and ethyl caproate, while the overexpression of ATF2 affected the concentrations of ethyl acetate and isoamyl acetate to a lesser degree. The overexpression of IAH1 resulted in a significant decrease in ethyl acetate, isoamyl acetate, hexyl acetate and 2-phenylethyl acetate. The overexpression of EHT1 resulted in a marked increase in ethyl caproate, ethyl caprylate and ethyl caprate. The flavour profile of the wines and distillates prepared using the modified strains were also significantly altered as indicated by formal sensory analysis. This study offers prospects for the development of wine yeast starter strains with optimized ester-producing capability that could assist winemakers in their effort to consistently produce wine and distillates such as brandy to definable flavour specifications and styles.

  15. Electron transport chain in a thermotolerant yeast.

    Science.gov (United States)

    Mejía-Barajas, Jorge A; Martínez-Mora, José A; Salgado-Garciglia, Rafael; Noriega-Cisneros, Ruth; Ortiz-Avila, Omar; Cortés-Rojo, Christian; Saavedra-Molina, Alfredo

    2017-04-01

    Yeasts capable of growing and surviving at high temperatures are regarded as thermotolerant. For appropriate functioning of cellular processes and cell survival, the maintenance of an optimal redox state is critical of reducing and oxidizing species. We studied mitochondrial functions of the thermotolerant Kluyveromyces marxianus SLP1 and the mesophilic OFF1 yeasts, through the evaluation of its mitochondrial membrane potential (ΔΨ m ), ATPase activity, electron transport chain (ETC) activities, alternative oxidase activity, lipid peroxidation. Mitochondrial membrane potential and the cytoplasmic free Ca 2+ ions (Ca 2+ cyt) increased in the SLP1 yeast when exposed to high temperature, compared with the mesophilic yeast OFF1. ATPase activity in the mesophilic yeast diminished 80% when exposed to 40° while the thermotolerant SLP1 showed no change, despite an increase in the mitochondrial lipid peroxidation. The SLP1 thermotolerant yeast exposed to high temperature showed a diminution of 33% of the oxygen consumption in state 4. The uncoupled state 3 of oxygen consumption did not change in the mesophilic yeast when it had an increase of temperature, whereas in the thermotolerant SLP1 yeast resulted in an increase of 2.5 times when yeast were grown at 30 o , while a decrease of 51% was observed when it was exposed to high temperature. The activities of the ETC complexes were diminished in the SLP1 when exposed to high temperature, but also it was distinguished an alternative oxidase activity. Our results suggest that the mitochondria state, particularly ETC state, is an important characteristic of the thermotolerance of the SLP1 yeast strain.

  16. Dry diamond wire sawing techniques to be used in an active environment

    International Nuclear Information System (INIS)

    Loftus, S.

    2003-01-01

    Dry diamond wire sawing techniques usable in an active environment has the following benefits: - Reduced personnel exposure time due the remote control and operation of the cutting equipment, the operator is positioned outside the active cell when controlling the equipment; - The equipment will be reusable with only the diamond cutting wire and the drive wheel rubber inserts coming into contact with potentially contaminated material; - The reduced impact on the existing ventilation systems from fumes or particulate blinding in-cell filters. - No dismantling work has to be carried out on the object to make it suitable for cutting using diamond wire cutting; - The diamond wire is the only piece of equipment subject to short-term replacement due to wear. The paper presents the following issues: The project the equipment is to be used on; -The equipment to be used; - Cutting machine support frame; - Drive units; - Wire coolant device. The seconds part of the paper deals with in-active cutting trials. To produce a strategy for cutting up a vessel in an active facility, the cutting technique proposed for size reducing the vessel to be tested implies establishing its suitability before developing the cutting rig that will be used for the actual task. A mock-up of the vessel was manufactured and size reduced using an existing cutting rig located at the supplies works. This sets out and records the results of the trials performed to functionally demonstrate the adequacy of using a diamond wire to cut the vessel into several pieces. The trials were performed at Diamant Boart test facility in Brussels.The objectives of the vessel cutting trials were: - To assess if a double skinned mock-up of the vessel can be cut successfully, dry, using Diamant Boart diamond wire cooled using liquid nitrogen; - To optimise the cutting process to achieve maximum cutting speed, minimum nitrogen usage and optimise wire life; - To identify any changes to the cutting rig, heat exchanger or

  17. The influence of drying on the physiological quality of cape gooseberry (Physalis peruviana L. fruits added with active components

    Directory of Open Access Journals (Sweden)

    Yudy Ana Cabrera Ordoñez

    2017-10-01

    Full Text Available Dehydrated products added with active components (AC represent a healthy alternative for modern consumer. The aim of this research was to evaluate the influence of drying process conditions on the physiological quality attributes of cape gooseberry (Physalis peruviana L. impregnated under vacuum with AC and dehydrated. A factorial design was performed with two independent variables, 2 levels per variable (temperature: 50 and 60ºC, air velocity: 2.0 and 3.0 m.s-1 and three replicates per drying condition. In fact, cape gooseberry fruits were previously impregnated under vacuum with an emulsion containing calcium and vitamins B9, C, D3 and E, which were subjected to dehydration until a water activity of approximately 0.6. In addition, drying rate curves presented in all cases two periods of decreasing speed. An increase of drying temperature decreases the processing time, presenting a greater AC degradation, while the air velocity offers a non-significant effect. The treatment which have allowed an AC better retention and low processing times was 60° C and 2 m.s-1, reaching levels of 204.8 ± 10.5 mg, 137.0 ± 34.7 μg, 13.6 ± 0.9 mg, 2.2± 0.6 μg, 7.0±1.2 mg for calcium and vitamins B9, C, D3 and E, respectively per 50 g serving of dehydrated cape gooseberry. An integration of the vacuum impregnation process with conventional air-drying, represents an effective technological alternative, which confers a higher added value to cape gooseberry fruit.

  18. Antioxidant activity, the content of total phenols and flavonoids in the ethanol extracts of Mentha longifolia (L. Hudson dried by the use of different techniques

    Directory of Open Access Journals (Sweden)

    Stanisavljević Dragana M.

    2012-01-01

    Full Text Available In this study, we have examined the yield of extracted substances obtained by means of extraction using 70 % ethanol (v/v, the content of total phenols and flavonoids, as well as the antioxidant activity of the extracts obtained from the samples of the herbs dried by means of different techniques. Wild mint Mentha longifolia (L. Hudson was dried naturally in a laboratory oven at a temperature of 45 °C and in an absorptive low temperature condensation oven at 35°C. The highest yield of extracts was obtained from the naturally dried herbs and the lowest from the herbs dried in the low temperature condensation drying oven. The content of total phenols and flavonoids was determined by spectrophotometric methods with an FC reagent and by the complexation reaction with aluminium-chloride, respectively. The extract of the naturally dried herbs had the highest overall content of phenols (113.8±2.0 mg of gallic acid/g of the dry extract and flavonoids (106.7±0.3 mg of rutin/g of the dry extract. The highest antioxidant activity determined by the FRAP and DPPH assay was determined in the extracts obtained from naturally dried herbs (2.76±0.15 mmol Fe2+/mg of the dry extract and EC50=0.022±0.001 mg/ml, while the lowest was obtained from the extracts of herbs dried in the laboratory oven (1.13±0.11 mmol Fe2+/mg of the dry extract and EC50=0.033±0.001 mg/ml. The HPLC-DAD analysis result show that the greatest content of phenolic compounds show extract obtained from naturally dried plant material. The dominant phenolic component in the all extracts is Kaempferol 3-O-glucoside. The content of all phenolic compound strongly depend on the drying conditions.

  19. Estimating the opportunity costs of activities that cause degradation in tropical dry forest: Implications for REDD +

    NARCIS (Netherlands)

    Borrego, Armonia; Skutsch, Margaret

    2014-01-01

    The viability of national REDD + programs will depend in part on whether funds generated from sales of carbon credits are sufficient to cover the opportunity costs (OC) of forgone uses of the forest. We present the results of a study in which OC were estimated in dry tropical forest, in western

  20. Vaginal yeast infection

    Science.gov (United States)

    Yeast infection - vagina; Vaginal candidiasis; Monilial vaginitis ... Most women have a vaginal yeast infection at some time. Candida albicans is a common type of fungus. It is often found in small amounts ...

  1. Glucose de-repression by yeast AMP-activated protein kinase SNF1 is controlled via at least two independent steps.

    Science.gov (United States)

    García-Salcedo, Raúl; Lubitz, Timo; Beltran, Gemma; Elbing, Karin; Tian, Ye; Frey, Simone; Wolkenhauer, Olaf; Krantz, Marcus; Klipp, Edda; Hohmann, Stefan

    2014-04-01

    The AMP-activated protein kinase, AMPK, controls energy homeostasis in eukaryotic cells but little is known about the mechanisms governing the dynamics of its activation/deactivation. The yeast AMPK, SNF1, is activated in response to glucose depletion and mediates glucose de-repression by inactivating the transcriptional repressor Mig1. Here we show that overexpression of the Snf1-activating kinase Sak1 results, in the presence of glucose, in constitutive Snf1 activation without alleviating glucose repression. Co-overexpression of the regulatory subunit Reg1 of the Glc-Reg1 phosphatase complex partly restores glucose regulation of Snf1. We generated a set of 24 kinetic mathematical models based on dynamic data of Snf1 pathway activation and deactivation. The models that reproduced our experimental observations best featured (a) glucose regulation of both Snf1 phosphorylation and dephosphorylation, (b) determination of the Mig1 phosphorylation status in the absence of glucose by Snf1 activity only and (c) a regulatory step directing active Snf1 to Mig1 under glucose limitation. Hence it appears that glucose de-repression via Snf1-Mig1 is regulated by glucose via at least two independent steps: the control of activation of the Snf1 kinase and directing active Snf1 to inactivating its target Mig1. © 2014 FEBS.

  2. The Association between Dry Eye Disease and Physical Activity as well as Sedentary Behavior: Results from the Osaka Study

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    Motoko Kawashima

    2014-01-01

    Full Text Available Purpose. To assess the association of dry eye disease (DED with physical activity and sedentary behavior. Methods. The cross-sectional survey conducted included Japanese office workers who use visual display terminals (n=672. DED was assessed according to the Japanese Dry Eye Diagnostic Criteria, and participants were categorized into “definite DED,” “probable DED,” or “non-DED” groups based on the results of DED examinations. Physical activity and sedentary behavior of participants were assessed using the International Physical Activity Questionnaire (IPAQ, and physical activity level was calculated in metabolic equivalent units per week (MET, min/week. Participants were classified as having a high, moderate, or low level of physical activity. Results. Participants with abnormal tear break-up time (BUT (≤5 s were involved in sedentary behavior for significantly longer duration than those with normal BUT (P=0.035. Non-DED participants (14.5% tended to have higher levels of physical activity than definite DED participants (2.5%. Participants with definite DED had significantly lower MET scores than those with non-DED (P=0.025. Conclusions. Our findings suggest that a lower level of physical activity and sedentary behavior are associated with DED; however, longitudinal/intervention studies with large groups of participants are needed to validate these findings.

  3. The Association between Dry Eye Disease and Physical Activity as well as Sedentary Behavior: Results from the Osaka Study.

    Science.gov (United States)

    Kawashima, Motoko; Uchino, Miki; Yokoi, Norihiko; Uchino, Yuichi; Dogru, Murat; Komuro, Aoi; Sonomura, Yukiko; Kato, Hiroaki; Nishiwaki, Yuji; Kinoshita, Shigeru; Tsubota, Kazuo

    2014-01-01

    Purpose. To assess the association of dry eye disease (DED) with physical activity and sedentary behavior. Methods. The cross-sectional survey conducted included Japanese office workers who use visual display terminals (n = 672). DED was assessed according to the Japanese Dry Eye Diagnostic Criteria, and participants were categorized into "definite DED," "probable DED," or "non-DED" groups based on the results of DED examinations. Physical activity and sedentary behavior of participants were assessed using the International Physical Activity Questionnaire (IPAQ), and physical activity level was calculated in metabolic equivalent units per week (MET, min/week). Participants were classified as having a high, moderate, or low level of physical activity. Results. Participants with abnormal tear break-up time (BUT) (≤5 s) were involved in sedentary behavior for significantly longer duration than those with normal BUT (P = 0.035). Non-DED participants (14.5%) tended to have higher levels of physical activity than definite DED participants (2.5%). Participants with definite DED had significantly lower MET scores than those with non-DED (P = 0.025). Conclusions. Our findings suggest that a lower level of physical activity and sedentary behavior are associated with DED; however, longitudinal/intervention studies with large groups of participants are needed to validate these findings.

  4. Levedura de cana-de-açúcar spray dry na alimentação de suínos na fase de crescimento e terminação Sugar cane spray dry yeast on growing and finishing pigs feeding

    Directory of Open Access Journals (Sweden)

    A.R. Poveda-Parra

    2013-02-01

    Full Text Available Foi estudado o valor nutricional (digestibilidade total e ileal de duas leveduras spray dry (cana-de-açúcar - LEV35 e cerveja+cana-de-açúcar - LEV40 e o efeito da sua inclusão em rações para suínos na fase de crescimento e terminação. Os valores de ED (kcal/kg da LEV35 e da LEV40 foram 3.496 e 3.901 e EM (kcal/kg foram 3.475 e 3.862, respectivamente. Os valores de lisina, metionina+cistina e treonina digestível para a levedura de cana-de-açúcar e da levedura de cerveja+cana-de-açúcar são 2,66 e 2,64, 1,11 e 1,03, 1,95 e 1,92, respectivamente. No desempenho foram utilizados 40 suínos com peso inicial de 34,39± 7,57kg (crescimento e de 62,45± 5,68kg (terminação, distribuídos em delineamento inteiramente casualizado com cinco níveis de inclusão (0, 5, 10, 15 e20% da LEV35. Na fase de crescimento, houve piora do GDP e da CA com o aumento da inclusão. Na fase de terminação, porém, houve efeito quadrático para o CDR, sendo o melhor nível 3.32%. Da mesma forma, ocorreu piora linear para o GDP, CA, peso de carcaça quente, rendimento de carcaça fria e peso de pernil. Os resultados sugerem que a adição de níveis crescentes da LEV35 pode prejudicar o desempenho dos suínos.The nutritional value of two spray dry yeast (sugar cane - SCYSD and brewer+sugar cane - BYSD and their inclusion effects on growing and finishing pigs feeding was studied. The DE (kcal/kg values for SCYSD and BYSD were 3.496 and 3.901 and for ME (kcal/kg they were 3.475 and 3.862. The values of digestible lysine, methionine+cistine and threonine for SCYSD and BYSD were: 2.66 and 2.64%; 1.11 and 1.03%: 1.95 and 1.92%. 40 pigs with initial weight of 34.39±7.57kg (growing and 62.45±5.68kg (finishing, allotted in a completely randomized design with five levels of SCYSD inclusion were used in the performance assay. In the growing phase, there was an impairing on DWG and F:G, however, in the finishing phase, DFI presented a quadratic effect, being 3

  5. Phytase production by Rhizopus microsporus var. microsporus biofilm: characterization of enzymatic activity after spray drying in presence of carbohydrates and nonconventional adjuvants.

    Science.gov (United States)

    Sato, Vanessa Sayuri; Jorge, João Atílio; Oliveira, Wanderley Pereira; Souza, Claudia Regina Fernandez; Guimarães, Luis Henrique Souza

    2014-02-28

    Microbial phytases are enzymes with biotechnological interest for the feed industry. In this article, the effect of spray-drying conditions on the stability and activity of extracellular phytase produced by R. microsporus var. microsporus biofilm is described. The phytase was spray-dried in the presence of starch, corn meal (>150 μm), soy bean meal (SB), corn meal (drying adjuvants. The residual enzyme activity after drying ranged from 10.7% to 60.4%, with SB and CM standing out as stabilizing agents. Water concentration and residual enzyme activity were determined in obtained powders as a function of the drying condition. When exposed to different pH values, the SB and CM products were stable, with residual activity above 50% in the pH range from 4.5 to 8.5 for 60 min. The use of CM as drying adjuvant promoted the best retention of enzymatic activity compared with SB. Spray drying of the R. microsporus var. microsporus phytase using different drying adjuvants showed interesting results, being quite feasible with regards their biotechnological applications, especially for poultry diets.

  6. Dry Eye

    Science.gov (United States)

    ... Eye » Facts About Dry Eye Listen Facts About Dry Eye Fact Sheet Blurb The National Eye Institute (NEI) ... and their families search for general information about dry eye. An eye care professional who has examined the ...

  7. Separable Crossover-Promoting and Crossover-Constraining Aspects of Zip1 Activity during Budding Yeast Meiosis.

    Directory of Open Access Journals (Sweden)

    Karen Voelkel-Meiman

    2015-06-01

    Full Text Available Accurate chromosome segregation during meiosis relies on the presence of crossover events distributed among all chromosomes. MutSγ and MutLγ homologs (Msh4/5 and Mlh1/3 facilitate the formation of a prominent group of meiotic crossovers that mature within the context of an elaborate chromosomal structure called the synaptonemal complex (SC. SC proteins are required for intermediate steps in the formation of MutSγ-MutLγ crossovers, but whether the assembled SC structure per se is required for MutSγ-MutLγ-dependent crossover recombination events is unknown. Here we describe an interspecies complementation experiment that reveals that the mature SC is dispensable for the formation of Mlh3-dependent crossovers in budding yeast. Zip1 forms a major structural component of the budding yeast SC, and is also required for MutSγ and MutLγ-dependent crossover formation. Kluyveromyces lactis ZIP1 expressed in place of Saccharomyces cerevisiae ZIP1 in S. cerevisiae cells fails to support SC assembly (synapsis but promotes wild-type crossover levels in those nuclei that progress to form spores. While stable, full-length SC does not assemble in S. cerevisiae cells expressing K. lactis ZIP1, aggregates of K. lactis Zip1 displayed by S. cerevisiae meiotic nuclei are decorated with SC-associated proteins, and K. lactis Zip1 promotes the SUMOylation of the SC central element protein Ecm11, suggesting that K. lactis Zip1 functionally interfaces with components of the S. cerevisiae synapsis machinery. Moreover, K. lactis Zip1-mediated crossovers rely on S. cerevisiae synapsis initiation proteins Zip3, Zip4, Spo16, as well as the Mlh3 protein, as do the crossovers mediated by S. cerevisiae Zip1. Surprisingly, however, K. lactis Zip1-mediated crossovers are largely Msh4/Msh5 (MutSγ-independent. This separation-of-function version of Zip1 thus reveals that neither assembled SC nor MutSγ is required for Mlh3-dependent crossover formation per se in budding yeast

  8. Increasing the yeast yield in alcohol fermentation

    Energy Technology Data Exchange (ETDEWEB)

    Pelc, A; Vamos, E; Varga, L; Gavalya, S; Dolanszky, F

    1964-02-01

    The yeast and ethanol yields (the latter being based on the substrate) are enhanced by adding the substrate (molasses) gradually to the suspension of inoculating yeast during the main fermentation period, passing air through the mash, ceasing both substrate addition and aeration at the end of the main period, and allowing the process to come to an end. This way 12 to 14 kg yeast (dry weight)/100 l ethanol could be obtained within 16 to 24 hours and the yeast obtained could be used as the inoculum for the next charge. For example: 11 to 16 kg yeast (or 18 to 25 l yeast suspension from the preceding charge, containing 18 to 20% dry matter) is kept in 30 to 35 l H/sub 2/SO/sub 4/ (0.74 g/100 ml) for 1 hour, diluted with H/sub 2/O and 30 kg sterile molasses to 300 l, kept at 30 to 32/sup 0/ with mild aeration for 2 hours, 1900 l 30/sup 0/ H/sub 2/O added, then 1 m/sup 3/ air/m/sup 2//hour is passed through the mixture, with the addition of 270 kg sterile molasses, and a solution of 8 kg superphosphate and 5 kg (NH/sub 4/)/sub 2/SO/sub 4/ in 100 l H/sub 2/O, the latter being added in 5 portions over 2 hours. Molasses (600 kg) is added during the main period, maintaining the pH at 5 (H/sub 2/SO/sub 4/), and the temperature at 30/sup 0/, then aeration is ceased and the mixture kept until fermentation proceeds. The 3000 l medium contains 9.6% ethanol and 1.38% yeast, respectively.

  9. Bags with oven-dried moss for the active monitoring of airborne trace elements in urban areas

    International Nuclear Information System (INIS)

    Giordano, S.; Adamo, P.; Monaci, F.; Pittao, E.; Tretiach, M.; Bargagli, R.

    2009-01-01

    To define a harmonized methodology for the use of moss and lichen bags as active monitoring devices of airborne trace elements in urban areas, we evaluated the element accumulation in bags exposed in Naples in different spring weather conditions for 6- and 12-weeks. Three different pre-exposure treatments were applied to moss and lichen materials: water-washing, acid-washing and oven-drying. During the different exposure periods in the Naples urban environment the moss accumulated always higher amounts of elements (except Hg) than lichens and the element accumulation increased during wetter weather and higher PM 10 conditions. The oven pre-treatment did not substantially modify the morphology and element composition of moss and the exposure in bags of this material for 6-weeks was sufficient to detect the pattern of airborne trace elements. - A 6-week exposure with oven-dried moss bags resulted a suitable approach to evaluate airborne trace elements in a Mediterranean urban environment.

  10. Multiple Taf subunits of TFIID interact with Ino2 activation domains and contribute to expression of genes required for yeast phospholipid biosynthesis.

    Science.gov (United States)

    Hintze, Stefan; Engelhardt, Maike; van Diepen, Laura; Witt, Eric; Schüller, Hans-Joachim

    2017-12-01

    Expression of phospholipid biosynthetic genes in yeast requires activator protein Ino2 which can bind to the UAS element inositol/choline-responsive element (ICRE) and trigger activation of target genes, using two separate transcriptional activation domains, TAD1 and TAD2. However, it is still unknown which cofactors mediate activation by TADs of Ino2. Here, we show that multiple subunits of basal transcription factor TFIID (TBP-associated factors Taf1, Taf4, Taf6, Taf10 and Taf12) are able to interact in vitro with activation domains of Ino2. Interaction was no longer observed with activation-defective variants of TAD1. We were able to identify two nonoverlapping regions in the N-terminus of Taf1 (aa 1-100 and aa 182-250) each of which could interact with TAD1 of Ino2 as well as with TAD4 of activator Adr1. Specific missense mutations within Taf1 domain aa 182-250 affecting basic and hydrophobic residues prevented interaction with wild-type TAD1 and caused reduced expression of INO1. Using chromatin immunoprecipitation we demonstrated Ino2-dependent recruitment of Taf1 and Taf6 to ICRE-containing promoters INO1 and CHO2. Transcriptional derepression of INO1 was no longer possible with temperature-sensitive taf1 and taf6 mutants cultivated under nonpermissive conditions. This result supports the hypothesis of Taf-dependent expression of structural genes activated by Ino2. © 2017 John Wiley & Sons Ltd.

  11. Influence of Different Drying Treatments and Extraction Solvents on the Metabolite Profile and Nitric Oxide Inhibitory Activity of Ajwa Dates.

    Science.gov (United States)

    Abdul-Hamid, Nur Ashikin; Abas, Faridah; Ismail, Intan Safinar; Shaari, Khozirah; Lajis, Nordin H

    2015-11-01

    This study aimed to examine the variation in the metabolite profiles and nitric oxide (NO) inhibitory activity of Ajwa dates that were subjected to 2 drying treatments and different extraction solvents. (1)H NMR coupled with multivariate data analysis was employed. A Griess assay was used to determine the inhibition of the production of NO in RAW 264.7 cells treated with LPS and interferon-γ. The oven dried (OD) samples demonstrated the absence of asparagine and ascorbic acid as compared to the freeze dried (FD) dates. The principal component analysis showed distinct clusters between the OD and FD dates by the second principal component. In respect of extraction solvents, chloroform extracts can be distinguished by the absence of arginine, glycine and asparagine compared to the methanol and 50% methanol extracts. The chloroform extracts can be clearly distinguished from the methanol and 50% methanol extracts by first principal component. Meanwhile, the loading score plot of partial least squares analysis suggested that beta glucose, alpha glucose, choline, ascorbic acid and glycine were among the metabolites that were contributing to higher biological activity displayed by FD and methanol extracts of Ajwa. The results highlight an alternative method of metabolomics approach for determination of the metabolites that contribute to NO inhibitory activity. The association between metabolite profiles and nitric oxide (NO) inhibitory activity of the various extracts of Ajwa dates was evaluated by utilizing partial least squares (PLS) model. The validated PLS model can be employed to predict the NO inhibitory activity of new samples of date fruits based on their NMR spectra which was important for assessing fruit quality. The information gained might be used as guidance for quality control, nutritional values and as a basis for the preparation of any food supplements for human health that employs date palm fruit as the raw material. © 2015 Institute of Food

  12. The Effect of Dry Needling Compared With Ischemic Pressure on Pain Intensity on Active Trigger Point in Upper Trapezius Muscle

    Directory of Open Access Journals (Sweden)

    Maryam Ziaeifar

    2013-07-01

    Full Text Available Objective: Myofascial trigger point is one of the most common causes of musculoskeletal pain and disorders. Myofascial trigger point in upper trapezius has been reported as a frequent symptom in patients with neck and thoracic pain. The purpose of this study was to investigate the effect of dry needling compared with ischemic pressure on active trigger point in upper trapezius muscle. Materials & Methods: 32 women with active myofascial trigger point in upper trapezius muscle participated in this randomized clinical trial (RCT study. The subjects were randomly assigned into two groups: dry needling (N=15 and ischemic pressure (N=17. The visual analogue scale (VAS was used to assess the pain intensity before and after treatment in both groups. Paired t-test was used to determine any significant difference in pain intensity after treatment sessions compared with pre-treatment score in control and experimental group. Analysis of Covariance (ANCOVA was calculated to determine the significance of differences between the control and experimental groups in post-test scores, with pre-treatment scores used as covariates in the analysis. Results: Statistical analysis (paired t-test revealed significant decrease in pain intensity after treatment sessions in control and experimental group (P=0.00 compared with pre-treatment score. In the ANCOVA, controlling for pre-test scores, no significant difference was found between the two groups (P=0.8. Conclusion: It seems that that both dry needling and ischemic pressure are effective in improvement in the pain intensity in subjects with myofascial trigger points. However, dry needling can be used by clinicians and therapist in physiotherapy clinics.

  13. The effect of drying temperatures on antioxidant activity, phenolic compounds, fatty acid composition and tocopherol contents in citrus seed and oils.

    Science.gov (United States)

    Al Juhaimi, Fahad; Özcan, Mehmet Musa; Uslu, Nurhan; Ghafoor, Kashif

    2018-01-01

    In this study, the effect of drying temperature on antioxidant activity, phenolic compounds, fatty acid composition and tocopherol content of citrus seeds and oils were studied. Kinnow mandarin seed, dried at 60 °C, exhibited the highest antioxidant activity. Orlendo orange seed had the maximum total phenolic content and α-tocopherol content, with a value of 63.349 mg/100 g and 28.085 mg/g (control samples), respectively. The antioxidant activity of Orlendo orange seed (63.349%) was higher than seeds of Eureka lemon (55.819%) and Kinnow mandarin (28.015%), while the highest total phenolic content was found in seeds of Kinnow mandarin, followed by Orlendo orange and Eureka lemon (113.132). 1.2-Dihydroxybenzene (13.171), kaempferol (10.780), (+)-catechin (9.341) and isorhamnetin (7.592) in mg/100 g were the major phenolic compounds found in Kinnow mandarin. Among the unsaturated fatty acids, linoleic acid was the most abundant acid in all oils, which varied from 44.4% (dried at 80 °C) to 46.1% (dried at 70 °C), from 39.0% (dried at 60 °C) to 40.0% (dried at 70 °C). The total phenolic content, antioxidant activity and phenolic compounds of citrus seeds and tocopherol content of seed oils were significantly affected by drying process and varied depending on the drying temperature.

  14. The roles of the catalytic and noncatalytic activities of Rpd3L and Rpd3S in the regulation of gene transcription in yeast.

    Directory of Open Access Journals (Sweden)

    Daniella Yeheskely-Hayon

    Full Text Available In budding yeasts, the histone deacetylase Rpd3 resides in two different complexes called Rpd3L (large and Rpd3S (small that exert opposing effects on the transcription of meiosis-specific genes. By introducing mutations that disrupt the integrity and function of either Rpd3L or Rpd3S, we show here that Rpd3 function is determined by its association with either of these complexes. Specifically, the catalytic activity of Rpd3S activates the transcription of the two major positive regulators of meiosis, IME1 and IME2, under all growth conditions and activates the transcription of NDT80 only during vegetative growth. In contrast, the effects of Rpd3L depends on nutrients; it represses or activates transcription in the presence or absence of a nitrogen source, respectively. Further, we show that transcriptional activation does not correlate with histone H4 deacetylation, suggesting an effect on a nonhistone protein. Comparison of rpd3-null and catalytic-site point mutants revealed an inhibitory activity that is independent of either the catalytic activity of Rpd3 or the integrity of Rpd3L and Rpd3S.

  15. The Roles of the Catalytic and Noncatalytic Activities of Rpd3L and Rpd3S in the Regulation of Gene Transcription in Yeast

    Science.gov (United States)

    Yeheskely-Hayon, Daniella; Kotler, Anat; Stark, Michal; Hashimshony, Tamar; Sagee, Shira; Kassir, Yona

    2013-01-01

    In budding yeasts, the histone deacetylase Rpd3 resides in two different complexes called Rpd3L (large) and Rpd3S (small) that exert opposing effects on the transcription of meiosis-specific genes. By introducing mutations that disrupt the integrity and function of either Rpd3L or Rpd3S, we show here that Rpd3 function is determined by its association with either of these complexes. Specifically, the catalytic activity of Rpd3S activates the transcription of the two major positive regulators of meiosis, IME1 and IME2, under all growth conditions and activates the transcription of NDT80 only during vegetative growth. In contrast, the effects of Rpd3L depends on nutrients; it represses or activates transcription in the presence or absence of a nitrogen source, respectively. Further, we show that transcriptional activation does not correlate with histone H4 deacetylation, suggesting an effect on a nonhistone protein. Comparison of rpd3-null and catalytic-site point mutants revealed an inhibitory activity that is independent of either the catalytic activity of Rpd3 or the integrity of Rpd3L and Rpd3S. PMID:24358376

  16. Virgin olive oil yeasts: A review.

    Science.gov (United States)

    Ciafardini, Gino; Zullo, Biagi Angelo

    2018-04-01

    This review summarizes current knowledge on virgin olive oil yeasts. Newly produced olive oil contains solid particles and micro drops of vegetation water in which yeasts reproduce to become the typical microbiota of olive oil. To date, about seventeen yeast species have been isolated from different types of olive oils and their by-products, of which six species have been identified as new species. Certain yeast species contribute greatly to improving the sensorial characteristics of the newly produced olive oil, whereas other species are considered harmful as they can damage the oil quality through the production of unpleasant flavors and triacylglycerol hydrolysis. Studies carried out in certain yeast strains have demonstrated the presence of defects in olive oil treated with Candida adriatica, Nakazawaea wickerhamii and Candida diddensiae specific strains, while other olive oil samples treated with other Candida diddensiae strains were defect-free after four months of storage and categorized as extra virgin. A new acetic acid producing yeast species, namely, Brettanomyces acidodurans sp. nov., which was recently isolated from olive oil, could be implicated in the wine-vinegary defect of the product. Other aspects related to the activity of the lipase-producing yeasts and the survival of the yeast species in the flavored olive oils are also discussed. Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. Serum components and clinical efficacies of autologous serum eye drops in dry eye patients with active and inactive Sjogren syndrome.

    Science.gov (United States)

    Ma, I-Hsin; Chen, Lily Wei; Tu, Wen-Hui; Lu, Chia-Ju; Huang, Chien-Jung; Chen, Wei-Li

    2017-01-01

    Autologous serum eye drops are considered safe and efficient for the treatment of various ocular surface disorders, including dry eye diseases (DED) caused by the primary and secondary Sjogren syndrome (SS). However, the serum components in patients of SS may be different from those of normal patients and can thus lead to unpredictable therapeutic effects. This study divided the SS patients into active and inactive types based on the erythrocyte sedimentation rate and the presence or absence of active rheumatoid arthritis. We compared the serum components of these two groups with standard and multiplex enzyme linked immunosorbent assay arrays and predicted the therapeutic effects of topical autologous serum for the treatment of DED with ocular surface disease index (OSDI) and Oxford Schema scale (OSS). Hyaluronic acid and transforming growth factor b1 levels were significantly higher in the active SS group compared to the inactive SS group ( P Sjogren dry eye patients into active and inactive groups may appear as a reasonable method to predict the quality of autologous serum eye drops, but there seems to be no significant predictability to the therapeutic effects.

  18. Structure and function of yeast alcohol dehydrogenase

    Directory of Open Access Journals (Sweden)

    VLADIMIR LESKOVAC

    2000-04-01

    Full Text Available 1. Introduction 2. Isoenzymes of YADH 3. Substrate specificity 4. Kinetic mechanism 5. Primary structure 6. The active site 7. Mutations in the yeast enzyme 8. Chemical mechanism 9. Binding of coenzymes 10. Hydride transfer

  19. The yeast H+-ATPase Pma1 promotes Rag/Gtr-dependent TORC1 activation in response to H+-coupled nutrient uptake.

    Science.gov (United States)

    Saliba, Elie; Evangelinos, Minoas; Gournas, Christos; Corrillon, Florent; Georis, Isabelle; André, Bruno

    2018-03-23

    The yeast Target of Rapamycin Complex 1 (TORC1) plays a central role in controlling growth. How amino acids and other nutrients stimulate its activity via the Rag/Gtr GTPases remains poorly understood. We here report that the signal triggering Rag/Gtr-dependent TORC1 activation upon amino-acid uptake is the coupled H + influx catalyzed by amino-acid/H + symporters. H + -dependent uptake of other nutrients, ionophore-mediated H + diffusion, and inhibition of the vacuolar V-ATPase also activate TORC1. As the increase in cytosolic H + elicited by these processes stimulates the compensating H + -export activity of the plasma membrane H + -ATPase (Pma1), we have examined whether this major ATP-consuming enzyme might be involved in TORC1 control. We find that when the endogenous Pma1 is replaced with a plant H + -ATPase, H + influx or increase fails to activate TORC1. Our results show that H + influx coupled to nutrient uptake stimulates TORC1 activity and that Pma1 is a key actor in this mechanism. © 2018, Saliba et al.

  20. Electro-Hydrodynamics and Kinetic Modeling of Dry and Humid Air Flows Activated by Corona Discharges

    Science.gov (United States)

    P. Sarrette, J.; Eichwald, O.; Marchal, F.; Ducasse, O.; Yousfi, M.

    2016-05-01

    The present work is devoted to the 2D simulation of a point-to-plane Atmospheric Corona Discharge Reactor (ACDR) powered by a DC high voltage supply. The corona reactor is periodically crossed by thin mono filamentary streamers with a natural repetition frequency of some tens of kHz. The study compares the results obtained in dry air and in air mixed with a small amount of water vapour (humid air). The simulation involves the electro-dynamics, chemical kinetics and neutral gas hydrodynamics phenomena that influence the kinetics of the chemical species transformation. Each discharge lasts about one hundred of a nanosecond while the post-discharge occurring between two successive discharges lasts one hundred of a microsecond. The ACDR is crossed by a lateral dry or humid air flow initially polluted with 400 ppm of NO. After 5 ms, the time corresponding to the occurrence of 50 successive discharge/post-discharge phases, a higher NO removal rate and a lower ozone production rate are found in humid air. This change is due to the presence of the HO2 species formed from the H primary radical in the discharge zone.

  1. Hyperpolarized [U-(2) H, U-(13) C]Glucose reports on glycolytic and pentose phosphate pathway activity in EL4 tumors and glycolytic activity in yeast cells.

    Science.gov (United States)

    Timm, Kerstin N; Hartl, Johannes; Keller, Markus A; Hu, De-En; Kettunen, Mikko I; Rodrigues, Tiago B; Ralser, Markus; Brindle, Kevin M

    2015-12-01

    A resonance at ∼181 ppm in the (13) C spectra of tumors injected with hyperpolarized [U-(2) H, U-(13) C]glucose was assigned to 6-phosphogluconate (6PG), as in previous studies in yeast, whereas in breast cancer cells in vitro this resonance was assigned to 3-phosphoglycerate (3PG). These peak assignments were investigated here using measurements of 6PG and 3PG (13) C-labeling using liquid chromatography tandem mass spectrometry (LC-MS/MS) METHODS: Tumor-bearing mice were injected with (13) C6 glucose and the (13) C-labeled and total 6PG and 3PG concentrations measured. (13) C MR spectra of glucose-6-phosphate dehydrogenase deficient (zwf1Δ) and wild-type yeast were acquired following addition of hyperpolarized [U-(2) H, U-(13) C]glucose and again (13) C-labeled and total 6PG and 3PG were measured by LC-MS/MS RESULTS: Tumor (13) C-6PG was more abundant than (13) C-2PG/3PG and the resonance at ∼181 ppm matched more closely that of 6PG. (13) C MR spectra of wild-type and zwf1Δ yeast cells showed a resonance at ∼181 ppm after labeling with hyperpolarized [U-(2) H, U-(13) C]glucose, however, there was no 6PG in zwf1Δ cells. In the wild-type cells 3PG was approximately four-fold more abundant than 6PG CONCLUSION: The resonance at ∼181 ppm in (13) C MR spectra following injection of hyperpolarized [U-(2) H, U-(13) C]glucose originates predominantly from 6PG in EL4 tumors and 3PG in yeast cells. © 2014 Wiley Periodicals, Inc.

  2. Yeast Extract Promotes Cell Growth and Induces Production of Polyvinyl Alcohol-Degrading Enzymes

    Directory of Open Access Journals (Sweden)

    Min Li

    2011-01-01

    Full Text Available Polyvinyl alcohol-degrading enzymes (PVAases have a great potential in bio-desizing processes for its low environmental impact and low energy consumption. In this study, the effect of yeast extract on PVAases production was investigated. A strategy of four-point yeast extract addition was developed and applied to maximize cell growth and PVAases production. As a result, the maximum dry cell weight achieved was 1.48 g/L and the corresponding PVAases activity was 2.99 U/mL, which are 46.5% and 176.8% higher than the control, respectively. Applying this strategy in a 7 L fermentor increased PVAases activity to 3.41 U/mL. Three amino acids (glycine, serine, and tyrosine in yeast extract play a central role in the production of PVAases. These results suggest that the new strategy of four-point yeast extract addition could benefit PVAases production.

  3. Drying Methods Alter Angiotensin-I Converting Enzyme Inhibitory Activity, Antioxidant Properties, and Phenolic Constituents of African Mistletoe (Loranthus bengwensis L) Leaves.

    Science.gov (United States)

    Oboh, Ganiyu; Omojokun, Olasunkanmi Seun; Ademiluyi, Adedayo Oluwaseun

    2016-10-01

    This study investigated the most appropriate drying method (sun drying, oven drying, or air drying) for mistletoe leaves obtained from almond tree. The phenolic constituents were characterized using high-performance liquid chromatography-diode array detector, while the inhibitory effect of the aqueous extracts of the leaves on angiotensin-I converting enzyme (ACE) was determined in vitro as also the antioxidant properties. Oven-dried extract (kidney [276.09 μg/mL] and lungs [303.41 μg/mL]) had the highest inhibitory effect on ACE, while air-dried mistletoe extract (kidney [304.47 μg/mL] and lungs [438.72 μg/mL]) had the least. Furthermore, the extracts dose-dependently inhibited Fe(2+) and sodium nitroprusside-induced lipid peroxidation in rat's heart and kidney. Also, all extracts exhibited antioxidative properties as typified by their radical scavenging and Fe-chelating ability. Findings from this study revealed that oven drying is the best of the 3 drying methods used for mistletoe obtained from almond host tree, thus confirming that diversity in drying methods leads to variation in phenolic constituents and biological activity of plants. © The Author(s) 2015.

  4. Effects of Freeze-dried Mulberry on Antioxidant Activities and Fermented Characteristics of Yogurt during Refrigerated Storage

    OpenAIRE

    Sung, Jung-Min; Kim, Young-Boong; Kum, Jun-Seok; Choi, Yun-Sang; Seo, Dong-Ho; Choi, Hyun-Wook; Park, Jong-Dae

    2015-01-01

    This study investigated the effect of added freeze-dried mulberry fruit juice (FDMJ) (1, 3 and 5%) on the antioxidant activity and fermented characteristic of yogurt during refrigerated storage. A decrease in pH of yogurt and increase in acidity was observed during fermentation. The yogurts with FDMJ exhibited faster rate of pH reduction than control. Initial lactic acid bacteria count of yogurt was 6.49-6.94 Log CFU/g and increased above 9 Log CFU/g in control and 1% in FDMJ yogurt for 24 h....

  5. Phytochemical Profiles and Antimicrobial Activities of Allium cepa Red cv. and A. sativum Subjected to Different Drying Methods: A Comparative MS-Based Metabolomics.

    Science.gov (United States)

    Farag, Mohamed A; Ali, Sara E; Hodaya, Rashad H; El-Seedi, Hesham R; Sultani, Haider N; Laub, Annegret; Eissa, Tarek F; Abou-Zaid, Fouad O F; Wessjohann, Ludger A

    2017-05-08

    Plants of the Allium genus produce sulphur compounds that give them a characteristic (alliaceous) flavour and mediate for their medicinal use. In this study, the chemical composition and antimicrobial properties of Allium cepa red cv. and A. sativum in the context of three different drying processes were assessed using metabolomics. Bulbs were dried using either microwave, air drying, or freeze drying and further subjected to chemical analysis of their composition of volatile and non-volatile metabolites. Volatiles were collected using solid phase micro-extraction (SPME) coupled to gas chromatography-mass spectrometry (GC/MS) with 42 identified volatiles including 30 sulphur compounds, four nitriles, three aromatics, and three esters. Profiling of the polar non-volatile metabolites via ultra-performance liquid chromatography coupled to high resolution MS (UPLC/MS) annotated 51 metabolites including dipeptides, flavonoids, phenolic acids, and fatty acids. Major peaks in GC/MS or UPLC/MS contributing to the discrimination between A. sativum and A. cepa red cv. were assigned to sulphur compounds and flavonoids. Whereas sulphur conjugates amounted to the major forms in A. sativum , flavonoids predominated in the chemical composition of A. cepa red cv. With regard to drying impact on Allium metabolites, notable and clear separations among specimens were revealed using principal component analysis (PCA). The PCA scores plot of the UPLC/MS dataset showed closer metabolite composition of microwave dried specimens to freeze dried ones, and distant from air dried bulbs, observed in both A. cepa and A. sativum . Compared to GC/MS, the UPLC/MS derived PCA model was more consistent and better in assessing the impact of drying on Allium metabolism. A phthalate derivative was found exclusively in a commercial garlic preparation via GC/MS, of yet unknown origin. The freeze dried samples of both Allium species exhibited stronger antimicrobial activities compared to dried specimens

  6. Phytochemical Profiles and Antimicrobial Activities of Allium cepa Red cv. and A. sativum Subjected to Different Drying Methods: A Comparative MS-Based Metabolomics

    Directory of Open Access Journals (Sweden)

    Mohamed A. Farag

    2017-05-01

    Full Text Available Plants of the Allium genus produce sulphur compounds that give them a characteristic (alliaceous flavour and mediate for their medicinal use. In this study, the chemical composition and antimicrobial properties of Allium cepa red cv. and A. sativum in the context of three different drying processes were assessed using metabolomics. Bulbs were dried using either microwave, air drying, or freeze drying and further subjected to chemical analysis of their composition of volatile and non-volatile metabolites. Volatiles were collected using solid phase micro-extraction (SPME coupled to gas chromatography–mass spectrometry (GC/MS with 42 identified volatiles including 30 sulphur compounds, four nitriles, three aromatics, and three esters. Profiling of the polar non-volatile metabolites via ultra-performance liquid chromatography coupled to high resolution MS (UPLC/MS annotated 51 metabolites including dipeptides, flavonoids, phenolic acids, and fatty acids. Major peaks in GC/MS or UPLC/MS contributing to the discrimination between A. sativum and A. cepa red cv. were assigned to sulphur compounds and flavonoids. Whereas sulphur conjugates amounted to the major forms in A. sativum, flavonoids predominated in the chemical composition of A. cepa red cv. With regard to drying impact on Allium metabolites, notable and clear separations among specimens were revealed using principal component analysis (PCA. The PCA scores plot of the UPLC/MS dataset showed closer metabolite composition of microwave dried specimens to freeze dried ones, and distant from air dried bulbs, observed in both A. cepa and A. sativum. Compared to GC/MS, the UPLC/MS derived PCA model was more consistent and better in assessing the impact of drying on Allium metabolism. A phthalate derivative was found exclusively in a commercial garlic preparation via GC/MS, of yet unknown origin. The freeze dried samples of both Allium species exhibited stronger antimicrobial activities compared to

  7. Extraction condition optimization and effects of drying methods on physicochemical properties and antioxidant activities of polysaccharides from comfrey (Symphytum officinale L.) root.

    Science.gov (United States)

    Shang, Hongmei; Zhou, Haizhu; Duan, Mengying; Li, Ran; Wu, Hongxin; Lou, Yujie

    2018-06-01

    This study was designed to investigate the extraction conditions of polysaccharides from comfrey (Symphytum officinale L.) root (CRPs) using response surface methodology (RSM). The effects of three variables including liquid-solid ratio, extraction time and extraction temperature on the extraction yield of CRPs were taken into consideration. Moreover, the effects of drying methods including hot air drying (HD), vacuum drying (VD) and freeze drying (FD) on the physicochemical properties and antioxidant activities of CRPs were evaluated. The optimal conditions to extract the polysaccharides were as follows: liquid-solid ratio (15mL/g), extraction time (74min), and extraction temperature (95°C), allowed a maximum polysaccharides yield of 22.87%. Different drying methods had significant effects on the physicochemical properties of CRPs such as the chemical composition (contents of total polysaccharides and uronic acid), relative viscosity, solubility and molecular weight. CRPs drying with FD method showed stronger reducing power and radical scavenging capacities against DPPH and ABTS radicals compared with CRPs drying with HD and VD methods. Therefore, freeze drying served as a good method for keeping the antioxidant activities of polysaccharides from comfrey root. Copyright © 2018 Elsevier B.V. All rights reserved.

  8. Multi trace element analysis of dry biological materials by neutron activation analysis including a chemical group separation

    International Nuclear Information System (INIS)

    Weers, C.A.

    1980-01-01

    The principles of activation analysis and the practical aspects of neutron activation analysis are outlined. The limits which are set to accuracy and precision are defined. The description of the evaporation process is summarised in terms of the half-volume. This quantity is then used to define the resolving power. The formulation is checked by radiotracer experiments. Dried animal blood is used as the testing material. The pretreatment of the samples and (the development of) the destruction-evaporation apparatus is described. Four successive devices were built and tested. The development of the successive adsorption steps with active charcoal, Al 2 O 3 and coprecipitation with Fe(OH) 3 is presented. Seven groups of about 25 elements in total can be determined this way. The results obtained for standard reference materials are summarized and compared with literature data. (Auth.)

  9. The influence of calcination temperature on catalytic activities in a Co based catalyst for CO2 dry reforming

    International Nuclear Information System (INIS)

    Song, Sang-Hoon; Son, Ju-Hee; Budiman, Anatta Wahyu; Choi, Myoung-Jae; Chang, Tae-Sun; Shin, Chae-Ho

    2014-01-01

    The carbon dioxide dry reforming of methane (CDR) reaction could be thermodynamically favored in the range of 800 to 1,000 .deg. C. However, the catalyst in this reaction should be avoided at the calcination temperature over 800 .deg. C since strong metal support interaction (SMSI) in this temperature range can decrease activity due to loss of active sites. Therefore, we focused on optimizing the temperature of pretreatment and a comparison of surface characterization results for CDR. Results related to metal sintering over support, re-dispersion by changing of particle size of metal-support, and strong metal support interaction were observed and confirmed in this work. In our conclusion, optimum calcination temperature for a preparation of catalyst was proposed that 400 .deg. C showed a higher and more stable catalytic activity without changing of support characteristics

  10. METHANE DRY REFORMING OVER Ni SUPPORTED ON PINE SAWDUST ACTIVATED CARBON: EFFECTS OF SUPPORT SURFACE PROPERTIES AND METAL LOADING

    Directory of Open Access Journals (Sweden)

    Rafael García

    2015-05-01

    Full Text Available The influence of metal loading and support surface functional groups (SFG on methane dry reforming (MDR over Ni catalysts supported on pine-sawdust derived activated carbon were studied. Using pine sawdust as the catalyst support precursor, the smallest variety and lowest concentration of SFG led to best Ni dispersion and highest catalytic activity, which increased with Ni loading up to 3 Ni atoms nm-2. At higher Ni loading, the formation of large metal aggregates was observed, consistent with a lower "apparen" surface area and a decrease in catalytic activity. The H2/CO ratio rose with increasing reaction temperature, indicating that increasingly important side reactions were taking place in addition to MDR.

  11. Hepatoprotective Activity of Dried- and Fermented-Processed Virgin Coconut Oil

    Directory of Open Access Journals (Sweden)

    Z. A. Zakaria

    2011-01-01

    Full Text Available The present study aims to determine the hepatoprotective effect of MARDI-produced virgin coconut oils, prepared by dried- or fermented-processed methods, using the paracetamol-induced liver damage in rats. Liver injury induced by 3 g/kg paracetamol increased the liver weight per 100 g bodyweight indicating liver damage. Histological observation also confirms liver damage indicated by the presence of inflammations and necrosis on the respective liver section. Interestingly, pretreatment of the rats with 10, but not 1 and 5, mL/kg of both VCOs significantly (P<.05 reduced the liver damage caused by the administration of paracetamol, which is further confirmed by the histological findings. In conclusion, VCO possessed hepatoprotective effect that requires further in-depth study.

  12. Effects of hot air and freeze drying methods on antioxidant activity, colour and some nutritional characteristics of strawberry tree (Arbutus unedo L) fruit.

    Science.gov (United States)

    Orak, H H; Aktas, T; Yagar, H; İsbilir, S Selen; Ekinci, N; Sahin, F Hasturk

    2012-08-01

    Antioxidant activity, colour and some nutritional properties of hot air and freeze-dried strawberry tree (Arbutus unedo L.) fruits were investigated. Additionally, the effects of two pre-treatments, namely ethyl oleate and water blanching, were compared in terms of drying characteristics. For determination of antioxidant activities in ethanol extracts, two different analytical methods were used: 1,1-diphenyl-2-picrylhydrazyl scavenging activity and β-carotene bleaching activity. As a result, the ethyl oleate pre-treatment shortened the drying time by hot air method and gave a higher 1,1-diphenyl-2-picrylhydrazyl scavenging activity (82.16 ± 0.34%), total phenolic content (7.62 ± 1.09 µg GAE/g extract), ascorbic acid content (236.93 ± 20.14 mg/100 g), besides hydromethylfurfural was not observed. Freeze-dried fruits exhibited higher ascorbic acid content (368.63 ± 17.16 mg/100 g) than those fresh fruits (231.33 ± 19.51 mg/100 g) and nearly 1,1-diphenyl-2-picrylhydrazyl activity (93.52 ± 0.41 %) to fresh fruits (94.03 ± 1.18%). Colour characteristics, sugar content and mineral contents of fruits were significantly affected by pre-treatments and drying methods (p drying of strawberry tree fruits should bring a valuable and attractive foodstuff to food industry due to the rich nutritional components, antioxidant activity and colour. Another conclusion from this study is that the freeze-drying is the best drying method to keep the nutritional value, antioxidant activity and sensory properties of fruits.

  13. Enhanced phytate dephosphorylation by using Candida melibiosica yeast-based biofuel cell.

    Science.gov (United States)

    Hubenova, Yolina; Georgiev, Danail; Mitov, Mario

    2014-10-01

    We report for the first time that Candida melibiosica expresses enhanced phytase activity when grown under biofuel cell polarization in a nutrient-poor medium, containing only fructose as a carbohydrate source. Phytase activity during the cultivation under polarization reached up to 25 U per g dry biomass, exceeding with 20 ± 3 % those of the control. A participation of the enzyme in the adaptation processes to the stress conditions is proposed. In addition, steady-state electrical outputs were achieved during biofuel cell operation at continuous polarization under constant load. The obtained results show that C. melibiosica yeast-based biofuel cell could be used for simultaneous electricity generation and phytate bioremediation.

  14. Chemical composition, anti-oxidative activity and in vitro dry matter degradability of Kinnow mandarin fruit waste

    Directory of Open Access Journals (Sweden)

    Ravleen Kour

    2014-10-01

    Full Text Available Aim: Fruit processing and consumption yield a significant amount of by-products as waste, which can be used as potential nutrient suppliers for livestock. “Kinnow” (Citrus nobilis Lour x Citrus deliciosa Tenora is one of the most important citrus fruit crops of North Indian States. Its residues are rich in carbohydrates but poor in protein and account for approximately 55-60% of the raw weight of the fruit. Present study assessed the chemical composition and anti-oxidative activity of Kinnow mandarin fruit waste (KMW and scrutinized the impact of dietary incorporation of variable levels of KMW on in vitro dry matter digestibility (IVDMD. Materials and Methods: Sun dried and ground KMW was analyzed for proximate composition, fibre fractions and calcium and phosphorus content. Antioxidant potential of KMW as total phenolic count and 1-diphenyl-2-picrylhydrazyl (DPPH scavenging activity was assayed in an alcoholic extract of KMW. The effect of inclusion of KMW at variable levels (0-40% in the isonitrogenous concentrate mixtures on in vitro degradability of composite feed (concentrate mixture:Wheat straw; 40:60 was also carried out. Results: KMW after sun-drying contained 92.05% dry matter. The crude protein content of 7.60% indicates it being marginal in protein content, whereas nitrogen free extract content of 73.69% suggests that it is primarily a carbonaceous feedstuff. This observation was also supported by low neutral detergent fiber and acid detergent fiber content of 26.35% and 19.50%, respectively. High calcium content (0.92% vis-à-vis low phosphorus content (0.08%, resulted in wide Ca:P ratio (11.5 in KMW. High anti-oxidative potential of KMW is indicated by total phenolic content values of 17.1±1.04 mg gallic acid equivalents/g and DPPH free radicle scavenging activity 96.2 μg/ml (effective concentration 50. Mean IVDMD% of all the composite rations was found to be comparable (p>0.05 irrespective of the level of KMW inclusion

  15. Survival of commercial yeasts in the winery environment and their prevalence during spontaneous fermentations.

    Science.gov (United States)

    Blanco, P; Orriols, I; Losada, A

    2011-01-01

    Inoculation of active dry yeasts during the wine-making process has become a common practice in most wine-producing regions; this practice may affect the diversity of the indigenous population of Saccharomyces cerevisiae in the winery. The aim of this work was to study the incidence of commercial yeasts in the experimental winery of Estación de Viticultura e Enoloxía de Galicia (EVEGA) and their ability to lead spontaneous fermentations. To do this, 64 spontaneous fermentations were carried out in the experimental cellar of EVEGA over a period of 7 years. Samples were taken from must and at the beginning, vigorous and final stages of fermentation. A representative number of yeast colonies was isolated from each sample. S. cerevisiae strains were characterised by analysis of mitochondrial DNA restriction patterns. The results showed that although more than 40 different strains of S. cerevisiae were identified, only 10 were found as the dominant strain or in codominance with other strains in spontaneous fermentations. The genetic profiles (mtDNA-RFLPs) of eight of these strains were similar to those of different commercial yeasts that had been previously used in the EVEGA cellar. The remaining two strains were autochthonous ones that were able to reach implantation frequencies as high of those of commercial yeasts. These results clearly indicated that commercial wine yeasts were perfectly adapted to survive in EVEGA cellar conditions, and they successfully competed with the indigenous strains of S. cerevisiae, even during spontaneous fermentations. On the other hand, autochthonous dominant strains that presented desirable oenological traits could be of interest to preserve wine typicity.

  16. Effect of sun drying on microbes in non-conventional agricultural by ...

    African Journals Online (AJOL)

    However, dried beetroot contained significantly more yeast and moulds. ... The sun drying process is thus an efficient processing method for resource poor ... to reduce the microbial load in these animal feed sources and improve their shelf life.

  17. New biological deodrization device using dried activated sludge. Kanso odei wo mochiita shinki seibutsu dasshu sochi no kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    Hatakeyama, S.; Nagayasu, K.; Suwa, T.; Hayashitani, M.; Ito, H.; Habata, K.; Kitakaze, T. (Kawasaki Heavy Industries, Ltd., Tokyo (Japan))

    1993-10-20

    The new biological deodorization device was developed using dried activated sludge as deodorant. Activated sludge obtained from a waste water treatment plant was dried at room temperature to protect from extinction of microorganisms in it before its charge into the device, and washed by water only as required. Offensive odor substances were oxidation-decomposed by microorganism after their adsorption into sludge surfaces, while microorganisms survived for a long time while getting such substances as nutritive sources. As basic deodorization characteristics were studied with the experimental device and artificial odor gases, more than 99% of 200 and 2,000 ppm H2S were removed at space velocities of 400/h and 33/h, respectively, together with nine typical offensive odor substances. As the result of demonstration tests with the small test device installed in a public waste water treatment plant, a high deodorizing efficiency was retained for 10 months or more, and its running cost was as low as 75% of that of current systems because of only one necessary washing every month. 3 refs., 14 figs., 12 tabs.

  18. Tolerance of budding yeast Saccharomyces cerevisiae to ultra high pressure

    Science.gov (United States)

    Shibata, M.; Torigoe, M.; Matsumoto, Y.; Yamamoto, M.; Takizawa, N.; Hada, Y.; Mori, Y.; Takarabe, K.; Ono, F.

    2014-05-01

    Our studies on the tolerance of plants and animals against very high pressure of several GPa have been extended to a smaller sized fungus, the budding yeast Saccharomyces cerevisiae. Several pieces of budding yeast (dry yeast) were sealed in a small teflon capsule with a liquid pressure medium fluorinate, and exposed to 7.5 GPa by using a cubic anvil press. The pressure was kept constant for various duration of time from 2 to 24 h. After the pressure was released, the specimens were brought out from the teflon capsule, and they were cultivated on a potato dextrose agar. It was found that the budding yeast exposed to 7.5 GPa for up to 6 h showed multiplication. However, those exposed to 7.5 GPa for longer than 12 h were found dead. The high pressure tolerance of budding yeast is a little weaker than that of tardigrades.

  19. Target activation and radiological response of ARIES-IFE dry wall chamber

    International Nuclear Information System (INIS)

    El-Guebaly, L.A.; Henderson, D.L.; Wilson, P.P.H.; Abdou, A.E.

    2002-01-01

    The choice of target coating and hohlraum wall materials is among the most critical decisions to be made for inertial fusion energy (IFE) designs. Gold and gold/gadolinium have long been considered to be the coating and hohlraum wall materials of choice for direct drive (DD) and indirect drive (ID) targets, respectively, offering high target performance and low beam energy losses. More recently, a variety of other materials have been considered, including W, Pb, Pt, Pd, and Ag for the DD target coating and Au, W, Pb, Hg, Ta, Cs, and Hf for the hohlraum wall of the ID target. The choice of the coating/hohlraum material is a tradeoff between the target design elements such as safety, target physics, economics, etc. We identified the key safety issues and have investigated the neutron-induced irradiation effects of the candidate coating/hohlraum materials using the radiation chamber conditions of the ARIES-IFE dry wall concept. The safety requirements have specific impacts in terms of the coating/hohlraum materials choice

  20. A Short Review on the Catalytic Activity of Hydrotalcite-Derived Materials for Dry Reforming of Methane

    Directory of Open Access Journals (Sweden)

    Radosław Dębek

    2017-01-01

    Full Text Available Nickel-containing hydrotalcite-derived materials have been recently proposed as promising materials for methane dry reforming (DRM. Based on a literature review and on the experience of the authors, this review focuses on presenting past and recent achievements on increasing activity and stability of hydrotalcite-based materials for DRM. The use of different NiMgAl and NiAl hydrotalcite (HT precursors, various methods for nickel introduction into HT structure, calcination conditions and promoters are discussed. HT-derived materials containing nickel generally exhibit high activity in DRM; however, the problem of preventing catalyst deactivation by coking, especially below 700 °C, is still an open question. The proposed solutions in the literature include: catalyst regeneration either in oxygen atmosphere or via hydrogasification; or application of various promoters, such as Zr, Ce or La, which was proven to enhance catalytic stability.

  1. Dry socket

    Science.gov (United States)

    Alveolar osteitis; Alveolitis; Septic socket ... You may be more at risk for dry socket if you: Have poor oral health Have a ... after having a tooth pulled Have had dry socket in the past Drink from a straw after ...

  2. Baker's yeast: production of D- and L-3-hydroxy esters

    DEFF Research Database (Denmark)

    Dahl, Allan Carsten; Madsen, Jørgen Øgaard

    1998-01-01

    harvested while growing. In contrast, the stereoselectivity was shifted towards L-hydroxy esters when the oxo esters were added slowly to ordinary baker's yeast supplied with gluconolactone as co-substrate. The reduction rate with gluconolactone was increased by active aeration. Ethyl L-(S)-3......Baker's yeast grown under oxygen limited conditions and used in the reduction of 3-oxo esters results in a shift of the stereoselectivity of the yeast towards D-hydroxy esters as compared with ordinary baker's yeast. The highest degree of stereoselectivity was obtained with growing yeast or yeast......-hydroxybutanoate was afforded in >99% ee. Both enantiomers of ethyl 3-hydroxypentanoate, D-(R) in 96% ee and L-(S) in 93% ee, and of ethyl 4-chloro-3-hydroxybutanoate, D-(S) in 98% ee and L-(R) in 94% ee, were obtained. The results demonstrate that the stereoselectivity of baker's yeast can be controlled...

  3. Inhibition of platelet aggregation and in vitro free radical scavenging activity of dried fruiting bodies of Pleurotus eous.

    Science.gov (United States)

    Suseem, S R; Saral, Mary

    2015-07-01

    To evaluate the ethyl acetate, methanol and aqueous extracts of dried fruiting bodies of Pleurotus eous for its anti-platelet activity on human volunteer's blood. And also to analyze the free radical scavenging property of the extracts of P.eous by using various in vitro models. Anti-platelet activity of dried fruiting bodies of P.eous was evaluated by in vitro model using blood platelets. Inhibition of platelet aggregation was monitored after pre-incubation of platelets with the crude extracts of mushroom P.eous. Antioxidant activities of extracts of P.eous were evaluated by different in vitro experiments, namely, 1, 1-diphenyl-2-picryl hydrazyl (DPPH), superoxide, hydroxyl radical and lipid peroxide radical models. Crude extracts of mushroom P.eous inhibited platelet aggregation dose-dependently which was induced by adenosine diphosphate (ADP). At a maximum concentration of 10 mg/mL, methanol extract effected 64.02% inhibition of lipid per-oxidation and 50.12% scavenging effect on superoxide anion radical. Aqueous extract of P.eous have shown 69.43% chelating ability on ferrous ions, 24.27% scavenging effect on hydroxyl radical and 49.57% scavenging effect on DPPH radical at 10 mg/mL. Increasing concentrations of the extract were found to cause progressively decreasing of the intensity of absorbance. Anti-platelet effects could be related in part to the polyphenolic compounds present in the extracts. Antioxidant activity results indicated the free radical scavenging property of the extracts of P.eous which might be due to the high content of phenolic compounds and flavonoids.

  4. Antioxidant and Antibacterial Activity of the Beverage Obtained by Fermentation of Sweetened Lemon Balm (Melissa offi cinalis L. Tea with Symbiotic Consortium of Bacteria and Yeasts

    Directory of Open Access Journals (Sweden)

    Dragoljub D. Cvetković

    2014-01-01

    Full Text Available Kombucha is a fermented tea beverage which is traditionally prepared by fermenting sweetened black or green tea (Camellia sinensis L. with symbiotic consortium of bacteria and yeasts (SCOBY. In this study, lemon balm (Melissa offi cinalis L. was used as the only nitrogen source for kombucha fermentation. During the seven-day fermentation process, pH value, titratable acidity (TA, total phenolic content, phenolic compounds, and antioxidant activity against hydroxyl (˙OH and 1,1-diphenyl-2-picrylhydrazil (DPPH radicals were measured to detect the connection between the fermentation time and antioxidant and antibacterial activities of lemon balm kombucha. Antibacterial activity of fi nished beverages with optimum acidity (TA=4–4.5 g/L, the value which is confi rmed by long-time kombucha consumers, and enhanced acidity (TA=8.12 g/L was tested against eleven wild bacterial strains. The results showed that lemon balm could be successfully used as an alternative to C. sinensis L. for kombucha fermentation. Total phenolic content and antioxidant activity against DPPH radicals of lemon balm fermentation broth were higher than those of traditional kombucha. Rosmarinic acid is the main phenolic compound of the lemon balm-based kombucha that probably provides biological activity of the beverage. Judging from the EC50 values, kombucha beverages exhibited higher antioxidant activities compared with C. sinensis L. and M. offi cinalis L. infusions, which can probably be ascribed to SCOBY metabolites. Lemon balm kombucha with both optimum and enhanced acidity showed antibacterial activity, which can be primarily ascribed to acetic acid, but also to some other tea components and SCOBY metabolites.

  5. Antioxidant and Antibacterial Activity of the Beverage Obtained by Fermentation of Sweetened Lemon Balm
(Melissa officinalis L.) Tea with Symbiotic Consortium 
of Bacteria and Yeasts.

    Science.gov (United States)

    Velićanski, Aleksandra S; Cvetković, Dragoljub D; Markov, Siniša L; Šaponjac, Vesna T Tumbas; Vulić, Jelena J

    2014-12-01

    Kombucha is a fermented tea beverage which is traditionally prepared by fermenting sweetened black or green tea ( Camellia sinensis L.) with symbiotic consortium of bacteria and yeasts (SCOBY). In this study, lemon balm ( Melissa officinalis L.) was used as the only nitrogen source for kombucha fermentation. During the seven-day fermentation process, pH value, titratable acidity (TA), total phenolic content, phenolic compounds, and antioxidant activity against hydroxyl ( ˙ OH) and 1,1-diphenyl-2-picrylhydrazil (DPPH) radicals were measured to detect the connection between the fermentation time and antioxidant and antibacterial activities of lemon balm kombucha. Antibacterial activity of finished beverages with optimum acidity (TA=4-4.5 g/L), the value which is confirmed by long-time kombucha consumers, and enhanced acidity (TA=8.12 g/L) was tested against eleven wild bacterial strains. The results showed that lemon balm could be successfully used as an alternative to C. sinensis L. for kombucha fermentation. Total phenolic content and antioxidant activity against DPPH radicals of lemon balm fermentation broth were higher than those of traditional kombucha. Rosmarinic acid is the main phenolic compound of the lemon balm-based kombucha that probably provides biological activity of the beverage. Judging from the EC 50 values, kombucha beverages exhibited higher antioxidant activities compared with C. sinensis L. and M. officinalis L. infusions, which can probably be ascribed to SCOBY metabolites. Lemon balm kombucha with both optimum and enhanced acidity showed antibacterial activity, which can be primarily ascribed to acetic acid, but also to some other tea components and SCOBY metabolites.

  6. Down-regulation of Rad51 activity during meiosis in yeast prevents competition with Dmc1 for repair of double-strand breaks.

    Directory of Open Access Journals (Sweden)

    Yan Liu

    2014-01-01

    Full Text Available Interhomolog recombination plays a critical role in promoting proper meiotic chromosome segregation but a mechanistic understanding of this process is far from complete. In vegetative cells, Rad51 is a highly conserved recombinase that exhibits a preference for repairing double strand breaks (DSBs using sister chromatids, in contrast to the conserved, meiosis-specific recombinase, Dmc1, which preferentially repairs programmed DSBs using homologs. Despite the different preferences for repair templates, both Rad51 and Dmc1 are required for interhomolog recombination during meiosis. This paradox has recently been explained by the finding that Rad51 protein, but not its strand exchange activity, promotes Dmc1 function in budding yeast. Rad51 activity is inhibited in dmc1Δ mutants, where the failure to repair meiotic DSBs triggers the meiotic recombination checkpoint, resulting in prophase arrest. The question remains whether inhibition of Rad51 activity is important during wild-type meiosis, or whether inactivation of Rad51 occurs only as a result of the absence of DMC1 or checkpoint activation. This work shows that strains in which mechanisms that down-regulate Rad51 activity are removed exhibit reduced numbers of interhomolog crossovers and noncrossovers. A hypomorphic mutant, dmc1-T159A, makes less stable presynaptic filaments but is still able to mediate strand exchange and interact with accessory factors. Combining dmc1-T159A with up-regulated Rad51 activity reduces interhomolog recombination and spore viability, while increasing intersister joint molecule formation. These results support the idea that down-regulation of Rad51 activity is important during meiosis to prevent Rad51 from competing with Dmc1 for repair of meiotic DSBs.

  7. The mathematical description of the process of drying the grain of millet in the device with active hydromechanical mode

    Directory of Open Access Journals (Sweden)

    S. T. Antipov

    2016-01-01

    Full Text Available The basis for the creation of new designs dryers laid the mathematical description of the test process, taking into account the method of loading and handling of the product in the machine, how to supply coolant or other type of energy supply, the theoretical performance, and structural (geometric component of the apparatus. To simulate the process of our work was considered of cylindrical dryers with active hydrodynamic regime and microwave energy supply, one feature of which is the loading of the product in a stream tangential coolant flow. The object of the study was chosen millet grain, because of the high biological value and high prevalence in the southern regions of the Russian Federation. On the basis of theoretical analysis, it was decided to divide the mathematical model into two conditional components: the study of heat and mass transfer study of aerodynamic component of the drying process. In this paper, we have been disclosed in detail is the second part of the process. The basis of this model were the equations of motion of millet grains by Newton's second law. The coolant in the framework of the proposed model is considered to be a continuous medium, highly compressible and has an internal viscosity, described by the Navier-Stokes equations. The initial conditions of the mathematical model were the following assumptions: the speed of the mechanical motion elements are equal to zero, the initial density of the air environment in all nodes is the equilibrium density of the air, the initial velocity of the air quality in all nodes is zero. The boundary conditions can be described as the constancy of the flow temperature and humidity, and its displacement is directly design constraints of the drying chamber. This model will be useful for professionals engaged in the problems of calculation and design of drying equipment.

  8. Kinetics of alcoholic fermentation during the culturing of bakers' yeast

    Energy Technology Data Exchange (ETDEWEB)

    Franz, B

    1961-01-01

    A synthesis was made of the effects of various factors on the rate of fermentation by Saccharomyces cerevisiae. The rate obeyed the Michaelis-Menten equation, was independent of the concentration of yeast, was maximal at 20/sup 0/ (0.61 ml ethanol/g dry yeast/h), was not significantly affected between pH 6.5 and 3.0 but declined at 3.0, was inhibited by ethanol at a rate proportional to the concentration squared (at ethanol = 12 volume %, the fermentation rate was practically zero), and was enhanced by the addition of phosphorus when a P-poor yeast was employed.

  9. Cambial activity in dry and rainy season on branches from woody species growing in Brazilian Cerrado

    Science.gov (United States)

    Carmen R. Marcati; Silvia R. Machado; Diego Sotto Podadera; Natalia O. Totti de Lara; Fabio Bosio; Alex C. Wiedenhoeft

    2016-01-01

    Seasonal cambial activity was investigated in one- to three-year-old branch modules (branch constructional units) of ten woody species from cerrado sensu stricto, a savanna-like ecosystem, of southernBrazil. Relationships between cambial activity and environmental factors (precipitation, temperature,day length) and leaf production were tested using...

  10. Activities in support of licensing Ontario Hydro's Dry Storage Container for radioactive waste transportation

    International Nuclear Information System (INIS)

    Boag, J.M.; Lee, H.P.; Nadeau, E.; Taralis, D.; Sauve, R.G.

    1993-01-01

    The Dry Storage Container (DSC) is being developed by Ontario Hydro for the on-site storage and possible future transportation of used fuel. The DSC is essentially rectangular in shape with outer dimensions being approximately 3.5 m (H) x 2.1 m (W) x 2.2 m (L) and has a total weight of approximately 68 Mg when loaded with used fuel. The container cavity is designed to accommodate four standard fuel modules (each module contains 96 CANDU fuel bundles). The space between inner and outer steel linear (each about 12.7 mm thick) is filled with high-density reinforced shielding concrete (approximately 500 mm thick). Foam-core steel-lined impact limiters will be fitted around the container during transportation to provide impact protection. In addition, an armour ring will be installed around the flanged closure weld (inside the impact limiter) to provide protection from accidental pin impact. Testing and impact analyses have demonstrated that the DSC was able to withstand a 9 m top corner drop and a 1 m drop onto a cylindrical pin (at the welded containment flange) without compromising the structural integrity of the DSC. Thermal analysis of the DSC during simulated fire accident conditions has shown that at the end of the fire, the exterior wall and interior cavity wall temperatures were 503degC and 78degC, respectively. The maximum fuel sheath temperature predicted was 137degC which was below the maximum allowable temperature for the fuel. The FD-HEAT code used for this analysis was validated through a heat conduction test of an actual DSC wall section. (J.P.N.)

  11. Evaluation of the ability of commercial wine yeasts to form biofilms (mats) and adhere to plastic: implications for the microbiota of the winery environment.

    Science.gov (United States)

    Tek, Ee Lin; Sundstrom, Joanna F; Gardner, Jennifer M; Oliver, Stephen G; Jiranek, Vladimir

    2018-02-01

    Commercially available active dried wine yeasts are regularly used by winemakers worldwide to achieve reliable fermentations and obtain quality wine. This practice has led to increased evidence of traces of commercial wine yeast in the vineyard, winery and uninoculated musts. The mechanism(s) that enables commercial wine yeast to persist in the winery environment and the influence to native microbial communities on this persistence is poorly understood. This study has investigated the ability of commercial wine yeasts to form biofilms and adhere to plastic. The results indicate that the biofilms formed by commercial yeasts consist of cells with a combination of different lifestyles (replicative and non-replicative) and growth modes including invasive growth, bud elongation, sporulation and a mat sectoring-like phenotype. Invasive growth was greatly enhanced on grape pulp regardless of strain, while adhesion on plastic varied between strains. The findings suggest a possible mechanism that allows commercial yeast to colonise and survive in the winery environment, which may have implications for the indigenous microbiota profile as well as the population profile in uninoculated fermentations if their dissemination is not controlled. © FEMS 2018. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  12. Batch system for study of Cr(VI) Bio sorption by dried waste activated sludge

    International Nuclear Information System (INIS)

    Farzadkia, M.; Gholami, M.; Darvishi Cheshmeh Soltani, R.; Yaghmaeian, K.; Shams Khorramabadi, G.

    2009-01-01

    Activated sludge from wastewater treatment systems contains both bacteria and protozoa. The cell wall of bacteria essentially consists of various compounds, such as carboxyl, acidic polysaccharides,lipids, amino acids and other components. (Author)

  13. Schizosaccharomyces japonicus: the fission yeast is a fusion of yeast and hyphae.

    Science.gov (United States)

    Niki, Hironori

    2014-03-01

    The clade of Schizosaccharomyces includes 4 species: S. pombe, S. octosporus, S. cryophilus, and S. japonicus. Although all 4 species exhibit unicellular growth with a binary fission mode of cell division, S. japonicus alone is dimorphic yeast, which can transit from unicellular yeast to long filamentous hyphae. Recently it was found that the hyphal cells response to light and then synchronously activate cytokinesis of hyphae. In addition to hyphal growth, S. japonicas has many properties that aren't shared with other fission yeast. Mitosis of S. japonicas is referred to as semi-open mitosis because dynamics of nuclear membrane is an intermediate mode between open mitosis and closed mitosis. Novel genetic tools and the whole genomic sequencing of S. japonicas now provide us with an opportunity for revealing unique characters of the dimorphic yeast. © 2013 The Author. Yeast Published by John Wiley & Sons Ltd.

  14. Analysis of methanogenic activity in a thermophilic-dry anaerobic reactor: Use of fluorescent in situ hybridization

    International Nuclear Information System (INIS)

    Montero, B.; Garcia-Morales, J.L.; Sales, D.; Solera, R.

    2009-01-01

    Methanogenic activity in a thermophilic-dry anaerobic reactor was determined by comparing the amount of methane generated for each of the organic loading rates with the size of the total and specific methanogenic population, as determined by fluorescent in situ hybridization. A high correlation was evident between the total methanogenic activity and retention time [-0.6988Ln(x) + 2.667] (R 2 0.8866). The total methanogenic activity increased from 0.04 x 10 -8 mLCH 4 cell -1 day -1 to 0.38 x 10 -8 mLCH 4 cell -1 day -1 while the retention time decreased, augmenting the organic loading rates. The specific methanogenic activities of H 2 -utilizing methanogens and acetate-utilizing methanogens increased until they stabilised at 0.64 x 10 -8 mLCH 4 cell -1 day -1 and 0.33 x 10 -8 mLCH 4 cell -1 day -1 , respectively. The methanogenic activity of H 2 -utilizing methanogens was higher than acetate-utilizing methanogens, indicating that maintaining a low partial pressure of hydrogen does not inhibit the acetoclastic methanogenesis or the anaerobic process

  15. Occurrence of Killer Yeast Strains in Fruit and Berry Wine Yeast Populations

    Directory of Open Access Journals (Sweden)

    Gintare Gulbiniene

    2004-01-01

    Full Text Available Apple, cranberry, chokeberry and Lithuanian red grape wine yeast populations were used for the determination of killer yeast occurrence. According to the tests of the killer characteristics and immunity the isolated strains were divided into seven groups. In this work the activity of killer toxins purified from some typical strains was evaluated. The analysed strains produced different amounts of active killer toxin and some of them possessed new industrially significant killer properties. Total dsRNA extractions in 11 killer strains of yeast isolated from spontaneous fermentations revealed that the molecular basis of the killer phenomenon was not only dsRNAs, but also unidentified genetic determinants.

  16. Activation of Rab GTPase Sec4 by its GEF Sec2 is required for prospore membrane formation during sporulation in yeast Saccharomyces cerevisiae.

    Science.gov (United States)

    Suda, Yasuyuki; Tachikawa, Hiroyuki; Inoue, Ichiro; Kurita, Tomokazu; Saito, Chieko; Kurokawa, Kazuo; Nakano, Akihiko; Irie, Kenji

    2018-02-01

    Sec2 activates Sec4 Rab GTPase as a guanine nucleotide exchange factor for the recruitment of downstream effectors to facilitate tethering and fusion of post-Golgi vesicles at the plasma membrane. During the meiosis and sporulation of budding yeast, post-Golgi vesicles are transported to and fused at the spindle pole body (SPB) to form a de novo membrane, called the prospore membrane. Previous studies have revealed the role of the SPB outer surface called the meiotic outer plaque (MOP) in docking and fusion of post-Golgi vesicles. However, the upstream molecular machinery for post-Golgi vesicular fusion that facilitates prospore membrane formation remains enigmatic. Here, we demonstrate that the GTP exchange factor for Sec4, Sec2, participates in the formation of the prospore membrane. A conditional mutant in which the SEC2 expression is shut off during sporulation showed sporulation defects. Inactivation of Sec2 caused Sec4 targeting defects along the prospore membranes, thereby causing insufficient targeting of downstream effectors and cargo proteins to the prospore membrane. These results suggest that the activation of Sec4 by Sec2 is required for the efficient supply of post-Golgi vesicles to the prospore membrane and thus for prospore membrane formation/extension and subsequent deposition of spore wall materials. © FEMS 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  17. Label-free measurement of the yeast short chain TAG lipase activity by ESI-MS after one-step esterification.

    Science.gov (United States)

    Ham, Hye Jin; Seo, Jongcheol; Yoon, Hye-Joo; Shin, Seung Koo

    2017-03-01

    Triacylglycerol (TAG) lipases hydrolyze ester bonds in TAG and release diacylglycerol (DAG), monoacylglycerol (MAG), and FA. We present a one-step chemical derivatization method for label-free quantification of a mixture of TAG, DAG, and MAG following lipase assay by ESI-MS. Because the ionization efficiencies of TAG, DAG, and MAG are not identical, lipase reaction products, DAG and MAG, are derivatized to TAG species by esterifying their hydroxyl groups using acyl chloride, whose acyl chain contains one less (or one more) -CH 2 group than that of substrate TAG. This resulted in three TAG species that were separated by 14 Da from one another and exhibited similar ion responses representing their molar amounts in the mass spectra. A good linear correlation was observed between peak intensity ratios and molar ratios in calibration curve. This method enables simultaneous quantification of TAG, DAG, and MAG in lipase assay and, in turn, allows stoichiometric determination of the concentrations of FAs released from TAG and DAG separately. By applying this strategy to measure both TAG and DAG lipolytic activities of the yeast Tgl2 lipase, we demonstrated its usefulness in studying enzymatic catalysis, as lipase enzymes often show dissimilar activities toward these lipids. Copyright © 2017 by the American Society for Biochemistry and Molecular Biology, Inc.

  18. The yeast plasma membrane ATP binding cassette (ABC) transporter Aus1: purification, characterization, and the effect of lipids on its activity.

    Science.gov (United States)

    Marek, Magdalena; Milles, Sigrid; Schreiber, Gabriele; Daleke, David L; Dittmar, Gunnar; Herrmann, Andreas; Müller, Peter; Pomorski, Thomas Günther

    2011-06-17

    The ATP binding cassette (ABC) transporter Aus1 is expressed under anaerobic growth conditions at the plasma membrane of the yeast Saccharomyces cerevisiae and is required for sterol uptake. These observations suggest that Aus1 promotes the translocation of sterols across membranes, but the precise transport mechanism has yet to be identified. In this study, an extraction and purification procedure was developed to characterize the Aus1 transporter. The detergent-solubilized protein was able to bind and hydrolyze ATP. Mutagenesis of the conserved lysine to methionine in the Walker A motif abolished ATP hydrolysis. Likewise, ATP hydrolysis was inhibited by classical inhibitors of ABC transporters. Upon reconstitution into proteoliposomes, the ATPase activity of Aus1 was specifically stimulated by phosphatidylserine (PS) in a stereoselective manner. We also found that Aus1-dependent sterol uptake, but not Aus1 expression and trafficking to the plasma membrane, was affected by changes in cellular PS levels. These results suggest a direct interaction between Aus1 and PS that is critical for the activity of the transporter.

  19. An ortholog of farA of Aspergillus nidulans is implicated in the transcriptional activation of genes involved in fatty acid utilization in the yeast Yarrowia lipolytica

    International Nuclear Information System (INIS)

    Poopanitpan, Napapol; Kobayashi, Satoshi; Fukuda, Ryouichi; Horiuchi, Hiroyuki; Ohta, Akinori

    2010-01-01

    Research highlights: → POR1 is a Yarrowia lipolytica ortholog of farA involved in fatty acid response in A. nidulans. → Deletion of POR1 caused growth defects on fatty acids. → Δpor1 strain exhibited defects in the induction of genes involved in fatty acid utilization. -- Abstract: The yeast Yarrowia lipolytica effectively utilizes hydrophobic substrates such as fatty acids and n-alkanes. To identify a gene(s) regulating fatty acid utilization in Y. lipolytica, we first studied homologous genes to OAF1 and PIP2 of Saccharomyces cerevisiae, but their disruption did not change growth on oleic acid at all. We next characterized a Y. lipolytica gene, POR1 (primary oleate regulator 1), an ortholog of farA encoding a transcriptional activator that regulates fatty acid utilization in Aspergillus nidulans. The deletion mutant of POR1 was defective in the growth on various fatty acids, but not on glucose, glycerol, or n-hexadecane. It exhibited slight defect on n-decane. The transcriptional induction of genes involved in β-oxidation and peroxisome proliferation by oleate was distinctly diminished in the Δpor1 strains. These data suggest that POR1 encodes a transcriptional activator widely regulating fatty acid metabolism in Y. lipolytica.

  20. Volume reduction of dry active waste by use of a waste sorting table at the Brunswick nuclear power plant

    International Nuclear Information System (INIS)

    Snead, P.B.

    1988-01-01

    Carolina Power and Light Company's Brunswick nuclear power plant has been using a National Nuclear Corporation Model WST-18 Waste Sorting Table to monitor and sort dry active waste for segregating uncontaminated material as a means of low-level waste volume reduction. The WST-18 features 18 large-area, solid scintillation detectors arranged in a 3 x 6 array underneath a sorting/monitoring surface that is shielded from background radiation. An 11-week study at Brunswick showed that the use of the waste sorting table resulted in dramatic improvements in both productivity (man-hours expended per cubic foot of waste processed) and monitoring quality over the previous hand-probe frisking method. Use of the sorting table since the study has confirmed its effectiveness in volume reduction. The waste sorting table paid for its operation in volume reduction savings alone, without accounting for the additional savings from recovering reusable items

  1. Evaluation of radwaste minimization program of dry and wet active waste in the Laguna Verde Nuclear Power Plant

    International Nuclear Information System (INIS)

    Luna-Garza, Hector

    2001-01-01

    A growing rate of radwaste volume production combined with an increase of both, costs and associated dose involved in its treatment and disposition processes have created a serious problem to the Laguna Verde Nuclear Power Plant (BWR, two Units, 682 Mwe each) in Mexico. Due the lack of a Final Repository in the country, the solution in the short or long terms relies on the success of a continuous and aggressive minimization program mainly based on modifications and upgrades applied to these processes. Technical and administrative strategies adopted by LVNPP for the reduction of Liquid Effluents and Dry and Wet Active Waste in the next three years are described. Based on the results of the LVNPP current radwaste process systems, an estimated accumulation of 11,502 m 3 by the year 2035 will exceed the actual on-site storage capacity. If the strategies succeed, this production would fall to an expected manageable volume of 4067 m 3 . (author)

  2. Influence of Sodium Alginate on Hypoglycemic Activity of Metformin Hydrochloride in the Microspheres Obtained by the Spray Drying

    Directory of Open Access Journals (Sweden)

    Marta Szekalska

    2016-01-01

    Full Text Available Alginate microspheres with metformin hydrochloride were prepared by the spray drying method in order to improve residence time of drug in the stomach. Nine formulations (F1–F9 with various drug : polymer ratio (1 : 2, 1 : 1, and 2 : 1 and different sodium alginate concentration (1%, 2%, and 3% were evaluated for size, morphology, drug loading, Zeta potential, and swelling degree. In vitro drug release, mathematical release profile, and physical state of microspheres were also evaluated. Optimal formulation characterized by the highest drug loading was formulation F6 (drug : polymer ratio 2 : 1 and 2% alginate solution. Based on glucose uptake in Saccharomyces cerevisiae cells and α-amylase inhibition tests, it could be concluded that alginate microspheres enhance hypoglycemic activity of metformin hydrochloride evaluated in vitro. Designed microspheres are promising as alternative, multicompartment dosage form for metformin hydrochloride delivery.

  3. Effect of spray drying processing parameters on the insecticidal activity of two encapsulated formulations of baculovirus

    Science.gov (United States)

    The aim of this work was to evaluate the effect of spray dryer processing parameters on the process yield and insecticidal activity of baculovirus to support the development of this beneficial group of microbes as biopesticides. For each of two baculoviruses [granulovirus (GV) from Pieris rapae (L....

  4. Autogenous and drying shrinkage of sodium carbonate activated slag altered by limestone powder incorporation

    NARCIS (Netherlands)

    Yuan, B.; Yu, Q.L.; Dainese, E.; Brouwers, H.J.H.

    2017-01-01

    This paper aims to study the shrinkage mechanism of sodium carbonate activated slag containing limestone powder (LP). The workability, pore structure, reaction kinetics and strength development were characterized. The results show that the autogenous shrinkage increases when the dosage of LP is low

  5. Catalytic activity and effect of modifiers on Ni-based catalysts for the dry reforming of methane

    Energy Technology Data Exchange (ETDEWEB)

    Barroso-Quiroga, Maria Martha; Castro-Luna, Adolfo Eduardo [Facultad de Ingenieria y Ciencias Economico-Sociales INTEQUI-CONICET-UNSL, Av. 25 de Mayo 384 (5730) Villa Mercedes (S.L.) (Argentina)

    2010-06-15

    Ni catalysts supported on different ceramic oxides (Al{sub 2}O{sub 3}, CeO{sub 2}, La{sub 2}O{sub 3}, ZrO{sub 2}) were prepared by wet impregnation. The catalytic behavior toward hydrogen production through the dry reforming of methane using a fixed-bed reactor was evaluated under certain experimental conditions, and the catalyst supported on ZrO{sub 2} showed the highest stable activity during the period of time studied. The catalyst supported on CeO{sub 2} has a relatively good activity, but shows signs of deactivation after a certain time during the reaction. This catalyst was chosen to be studied after the addition of 0.5 wt% Li and K as activity modifiers. The introduction of the alkaline metals produces a reduction of the catalytic activity but a better stability over the reactant conversion time. The reverse water-gas shift reaction influences the global system of reactions, and as the results indicate, should be considered near equilibrium. (author)

  6. Impact of Storage Conditions on the Stability of Predominant Phenolic Constituents and Antioxidant Activity of Dried Piper betle Extracts

    Directory of Open Access Journals (Sweden)

    Ameena Ali

    2018-02-01

    Full Text Available The phenolic constituents in Piper betle are well known for their antioxidant potential; however, current literature has very little information on their stability under the influence of storage factors. Present study evaluated the stability of total phenolic content (TPC and antioxidant activity together with individual phenolic constituents (hydroxychavicol, eugenol, isoeugenol and allylpyrocatechol 3,4-diacetate present in dried Piper betle’s extract under different storage temperature of 5 and 25 °C with and without light for a period of six months. Both light and temperature significantly influenced TPC and its corresponding antioxidant activity over time. More than 95% TPC and antioxidant activity was retained at 5 °C in dark condition after 180 days of storage. Hydroxychavicol demonstrated the best stability with no degradation while eugenol and isoeugenol displayed moderate stability in low temperature (5 °C and dark conditions. 4-allyl-1,2-diacetoxybenzene was the only compound that underwent complete degradation. A new compound, 2,4-di-tert-butylphenol, was detected after five weeks of storage only in the extracts exposed to light. Both zero-order and first-order kinetic models were adopted to describe the degradation kinetics of the extract’s antioxidant activity. Zero-order displayed better fit with higher correlation coefficients (R2 = 0.9046 and the half-life was determined as 62 days for the optimised storage conditions (5 °C in dark conditions.

  7. Impact of Storage Conditions on the Stability of Predominant Phenolic Constituents and Antioxidant Activity of Dried Piper betle Extracts.

    Science.gov (United States)

    Ali, Ameena; Chong, Chien Hwa; Mah, Siau Hui; Abdullah, Luqman Chuah; Choong, Thomas Shean Yaw; Chua, Bee Lin

    2018-02-23

    The phenolic constituents in Piper betle are well known for their antioxidant potential; however, current literature has very little information on their stability under the influence of storage factors. Present study evaluated the stability of total phenolic content (TPC) and antioxidant activity together with individual phenolic constituents (hydroxychavicol, eugenol, isoeugenol and allylpyrocatechol 3,4-diacetate) present in dried Piper betle 's extract under different storage temperature of 5 and 25 °C with and without light for a period of six months. Both light and temperature significantly influenced TPC and its corresponding antioxidant activity over time. More than 95% TPC and antioxidant activity was retained at 5 °C in dark condition after 180 days of storage. Hydroxychavicol demonstrated the best stability with no degradation while eugenol and isoeugenol displayed moderate stability in low temperature (5 °C) and dark conditions. 4-allyl-1,2-diacetoxybenzene was the only compound that underwent complete degradation. A new compound, 2,4-di- tert -butylphenol, was detected after five weeks of storage only in the extracts exposed to light. Both zero-order and first-order kinetic models were adopted to describe the degradation kinetics of the extract's antioxidant activity. Zero-order displayed better fit with higher correlation coefficients ( R ² = 0.9046) and the half-life was determined as 62 days for the optimised storage conditions (5 °C in dark conditions).

  8. Biodiesel production from yeast Cryptococcus sp. using Jerusalem artichoke.

    Science.gov (United States)

    Sung, Mina; Seo, Yeong Hwan; Han, Shin; Han, Jong-In

    2014-03-01

    Jerusalem artichoke was investigated as a cheap substrate for the heterotrophic production using a lab yeast strain Cryptococcus sp. Using Response Surface Method, 54.0% of fructose yield was achieved at 12% of dried Jerusalem artichoke powder, 0.57% of nitric acid concentration, 117°C of reaction temperature, and 49min of reaction time. At this optimal condition, nitric acid showed the best catalytic activity toward inulin hydrolysis and also the resulting fructose hydrolyte supported the highest microbial growth compared with other acids. In addition, lipid productivity of 1.73g/L/d was achieved, which is higher than a defined medium using pure fructose as a substrate. Lipid quality was also found to be generally satisfactory as a feedstock for fuel, demonstrating Jerusalem artichoke could indeed be a good and cheap option for the purpose of biodiesel production. Copyright © 2013 Elsevier Ltd. All rights reserved.

  9. Correlation between the physicochemical properties of organic solvents and their biocompatibility toward epoxide hydrolase activity in whole-cells of a yeast, Rhodotorulasp

    CSIR Research Space (South Africa)

    Lotter, J

    2004-08-01

    Full Text Available in whole-cells of the yeast Rhodotorula sp. UOFS Y-0448 was investigated. No formal correlation between solvent biocompatibility and physicochemical properties was deductible, although the introduction of hydroxyl groups increased biocompatibility. 1...

  10. Water addition regulates the metabolic activity of ammonia oxidizers responding to environmental perturbations in dry subhumid ecosystems.

    Science.gov (United States)

    Hu, Hang-Wei; Macdonald, Catriona A; Trivedi, Pankaj; Holmes, Bronwyn; Bodrossy, Levente; He, Ji-Zheng; Singh, Brajesh K

    2015-02-01

    Terrestrial arid and semi-arid ecosystems (drylands) constitute about 41% of the Earth's land surface and are predicted to experience increasing fluctuations in water and nitrogen availability. Mounting evidence has confirmed the significant importance of ammonia-oxidizing archaea (AOA) and bacteria (AOB) in nitrification, plant nitrogen availability and atmospheric N2 O emissions, but their responses to environmental perturbations in drylands remain largely unknown. Here we evaluate how the factorial combinations of irrigation and fertilization in forests and land-use change from grassland to forest affects the dynamics of AOA and AOB following a 6-year dryland field study. Potential nitrification rates and AOA and AOB abundances were significantly higher in the irrigated plots, accompanied by considerable changes in community compositions, but their responses to fertilization alone were not significant. DNA-stable isotope probing results showed increased (13) CO2 incorporation into the amoA gene of AOA, but not of AOB, in plots receiving water addition, coupled with significantly higher net mineralization and nitrification rates. High-throughput microarray analysis revealed that active AOA assemblages belonging to Nitrosopumilus and Nitrosotalea were increasingly labelled by (13) CO2 following irrigation. However, no obvious effects of land-use changes on nitrification rates or metabolic activity of AOA and AOB could be observed under dry conditions. We provide evidence that water addition had more important roles than nitrogen fertilization in influencing the autotrophic nitrification in dryland ecosystems, and AOA are increasingly involved in ammonia oxidation when dry soils become wetted. © 2014 Society for Applied Microbiology and John Wiley & Sons Ltd.

  11. Impact of different spray-drying conditions on the viability of wine Saccharomyces cerevisiae strains.

    Science.gov (United States)

    Aponte, Maria; Troianiello, Gabriele Danilo; Di Capua, Marika; Romano, Raffaele; Blaiotta, Giuseppe

    2016-01-01

    Spray-drying (SD) is widely considered a suitable method to preserve microorganisms, but data regarding yeasts are still scanty. In this study, the effect of growing media, process variables and carriers over viability of a wild wine Saccharomyces (S.) cerevisiae LM52 was evaluated. For biomass production, the strain was grown (batch and fed-batch fermentation) in a synthetic, as well as in a beet sugar molasses based-medium. Drying of cells resuspended in several combinations of soluble starch and maltose was performed at different inlet and outlet temperatures. Under the best conditions-suspension in soluble starch plus maltose couplet to inlet and outlet temperatures of 110 and 55 °C, respectively-the loss of viability of S. cerevisiae LM52 was 0.8 ± 0.1 and 0.5 ± 0.2 Log c.f.u. g(-1) for synthetic and molasses-based medium, respectively. Similar results were obtained when S. cerevisiae strains Zymoflore F15 and EC1118, isolated from commercial active dry yeast (ADY), were tested. Moreover, powders retained a high vitality and showed good fermentation performances up to 6 month of storage, at both 4 and -20 °C. Finally, fermentation performances of different kinds of dried formulates (SD and ADY) compared with fresh cultures did not show significant differences. The procedure proposed allowed a small-scale production of yeast in continuous operation with relatively simple equipment, and may thus represent a rapid response-on-demand for the production of autochthonous yeasts for local wine-making.

  12. Genomic and Phenotypic Characterization of Yeast Biosensor for Deep-space Radiation

    Science.gov (United States)

    Marina, Diana B.; Santa Maria, Sergio; Bhattacharya, Sharmila

    2016-01-01

    The BioSentinel mission was selected to launch as a secondary payload onboard NASA Exploration Mission 1 (EM-1) in 2018. In BioSentinel, the budding yeast Saccharomyces cerevisiae will be used as a biosensor to measure the long-term impact of deep-space radiation to living organisms. In the 4U-payload, desiccated yeast cells from different strains will be stored inside microfluidic cards equipped with 3-color LED optical detection system to monitor cell growth and metabolic activity. At different times throughout the 12-month mission, these cards will be filled with liquid yeast growth media to rehydrate and grow the desiccated cells. The growth and metabolic rates of wild-type and radiation-sensitive strains in deep-space radiation environment will be compared to the rates measured in the ground- and microgravity-control units. These rates will also be correlated with measurements obtained from onboard physical dosimeters. In our preliminary long-term desiccation study, we found that air-drying yeast cells in 10% trehalose is the best method of cell preservation in order to survive the entire 18-month mission duration (6-month pre-launch plus 12-month full-mission periods). However, our study also revealed that desiccated yeast cells have decreasing viability over time when stored in payload-like environment. This suggests that the yeast biosensor will have different population of cells at different time points during the long-term mission. In this study, we are characterizing genomic and phenotypic changes in our yeast biosensor due to long-term storage and desiccation. For each yeast strain that will be part of the biosensor, several clones were reisolated after long-term storage by desiccation. These clones were compared to their respective original isolate in terms of genomic composition, desiccation tolerance and radiation sensitivity. Interestingly, clones from a radiation-sensitive mutant have better desiccation tolerance compared to their original isolate

  13. Effect of water activity and protective solutes on growth and subsequent survival to air-drying of Lactobacillus and Bifidobacterium cultures.

    Science.gov (United States)

    Champagne, Claude P; Raymond, Yves; Simon, Jean-Paul

    2012-08-01

    Probiotic cultures of Lactobacillus plantarum, Lactobacillus rhamnosus, Bifidobacterium longum, Lactobacillus casei and Lactobacillus acidophilus were grown in media having water activities (a (w)) adjusted between 0.99 and 0.94 with NaCl or with a mixture of glycerol and sucrose in order to find conditions of osmotic stress which would still allow for good growth. Cultures grown at a (w) = 0.96 or 0.99 were then recovered by centrifugation, added to a sucrose-phosphate medium and air-dried. In some assays, a 2-h osmotic stress was applied to the cell concentrate prior to air-drying. Assays were also carried out where betaine, glutamate and proline (BGP) supplements were added as protective compounds to the growth or drying media. For most strains, evidence of osmotic stress and benefits of BGP supplementation on growth occurred at a (w) = 0.96. Growing the cells in complex media adjusted at a (w) = 0.96 did not enhance their subsequent survival to air-drying, but applying the 2-h osmotic stress did. Addition of the BGP supplements to the growth medium or in the 2-h stress medium did not enhance survival to air-drying. Furthermore, addition of BGP to a sucrose-phosphate drying medium reduced survival of the cultures to air-drying. This study provides preliminary data for producers of probiotics who wish to use air-drying in replacement of freeze-drying for the stabilization of cultures.

  14. Effects of lignin-derived phenolic compounds on xylitol production and key enzyme activities by a xylose utilizing yeast Candida athensensis SB18.

    Science.gov (United States)

    Zhang, Jinming; Geng, Anli; Yao, Chuanyi; Lu, Yinghua; Li, Qingbiao

    2012-10-01

    Candida athensensis SB18 is potential xylitol producing yeast isolated in Singapore. It has excellent xylose tolerance and is able to produce xylitol in high titer and yield. However, by-products, such as phenolic compounds, derived in lignocellulosic biomass hydrolysate might negatively influence the performance of this strain for xylitol production. In this work, four potential phenolic inhibitors, such as vanillin, syringaldehyde, 4-hydroxybenzaldehyde and phenol, were evaluated for their inhibitory effects on xylitol production by C. athensensis SB18. Phenol was shown to be the most toxic molecule on this microorganism followed by syringaldehyde. Vanillin and 4-hydroxylbenzaldehyde was less toxic than phenol and syringaldehyde, with vanillin being the least toxic. Inhibition was insignificant when the total content of inhibitors was below 1.0 g/L. The presence of phenolic compounds affected the activity of xylose reductase, however not on that of xylitol dehydrogenase. C. athensensis SB18 is therefore a potential xylitol producer from hemicellulosic hydrolysate due to its assimilation of such phenolic inhibitors. Copyright © 2012 Elsevier Ltd. All rights reserved.

  15. Diuron in water: functional toxicity and intracellular detoxification patterns of active concentrations assayed in tandem by a yeast-based probe.

    Science.gov (United States)

    Dragone, Roberto; Cheng, Rachel; Grasso, Gerardo; Frazzoli, Chiara

    2015-04-01

    A study on the acute and chronic effects of the herbicide diuron was carried out. The test, basing on a yeast cell probe, investigated the interference with cellular catabolism and possible self-detoxification capacity of Saccharomyces cerevisiae. Aerobic respiration was taken as the toxicological end-point. Percentage interference (%r) with cellular respiration was measured in water by increased dissolved O2 concentration (ppm) after exposure to different doses. Interference was calculated through the comparison of respiratory activity of exposed and non-exposed cells. Short-term and long-term (6 and 24 h respectively) exposures were also considered. The test for short-term exposure gave positive %r values except that for 10-6 M (11.11%, 11.76%, 13.33% and 0% for 10-10 M, 10-8 M, 10-7 M and 10-6 M respectively). In the case of long-term exposure the test showed positive %r values, but less effect than short-term exposure until 10-8 M and much higher at 10-6 M (7.41%, 8.82%, 11.76% and 6.06% for 10-10 M, 10-8 M, 10-7 M and 10-6 M respectively). The findings of aerobic respiration as toxicological end-point were in agreement with known mechanisms of toxicity and intracellular detoxification for both the doses and exposure times employed.

  16. Loss of yeast peroxiredoxin Tsa1p induces genome instability through activation of the DNA damage checkpoint and elevation of dNTP levels.

    Directory of Open Access Journals (Sweden)

    Hei-Man Vincent Tang

    2009-10-01

    Full Text Available Peroxiredoxins are a family of antioxidant enzymes critically involved in cellular defense and signaling. Particularly, yeast peroxiredoxin Tsa1p is thought to play a role in the maintenance of genome integrity, but the underlying mechanism is not understood. In this study, we took a genetic approach to investigate the cause of genome instability in tsa1Delta cells. Strong genetic interactions of TSA1 with DNA damage checkpoint components DUN1, SML1, and CRT1 were found when mutant cells were analyzed for either sensitivity to DNA damage or rate of spontaneous base substitutions. An elevation in intracellular dNTP production was observed in tsa1Delta cells. This was associated with constitutive activation of the DNA damage checkpoint as indicated by phosphorylation of Rad9/Rad53p, reduced steady-state amount of Sml1p, and induction of RNR and HUG1 genes. In addition, defects in the DNA damage checkpoint did not modulate intracellular level of reactive oxygen species, but suppressed the mutator phenotype of tsa1Delta cells. On the contrary, overexpression of RNR1 exacerbated this phenotype by increasing dNTP levels. Taken together, our findings uncover a new role of TSA1 in preventing the overproduction of dNTPs, which is a root cause of genome instability.

  17. Diuron in Water: Functional Toxicity and Intracellular Detoxification Patterns of Active Concentrations Assayed in Tandem by a Yeast-Based Probe

    Directory of Open Access Journals (Sweden)

    Roberto Dragone

    2015-04-01

    Full Text Available A study on the acute and chronic effects of the herbicide diuron was carried out. The test, basing on a yeast cell probe, investigated the interference with cellular catabolism and possible self-detoxification capacity of Saccharomyces cerevisiae. Aerobic respiration was taken as the toxicological end-point. Percentage interference (%r with cellular respiration was measured in water by increased dissolved O2 concentration (ppm after exposure to different doses. Interference was calculated through the comparison of respiratory activity of exposed and non-exposed cells. Short-term and long-term (6 and 24 h respectively exposures were also considered. The test for short-term exposure gave positive %r values except that for 10−6 M (11.11%, 11.76%, 13.33% and 0% for 10−10 M, 10−8 M, 10−7 M and 10−6 M respectively. In the case of long-term exposure the test showed positive %r values, but less effect than short-term exposure until 10−8 M and much higher at 10−6 M (7.41%, 8.82%, 11.76% and 6.06% for 10−10 M, 10−8 M, 10−7 M and 10−6 M respectively. The findings of aerobic respiration as toxicological end-point were in agreement with known mechanisms of toxicity and intracellular detoxification for both the doses and exposure times employed.

  18. Effect of dry mycelium of Penicillium chrysogenum fertilizer on soil microbial community composition, enzyme activities and snap bean growth.

    Science.gov (United States)

    Wang, Bing; Liu, Huiling; Cai, Chen; Thabit, Mohamed; Wang, Pu; Li, Guomin; Duan, Ziheng

    2016-10-01

    The dry mycelium fertilizer (DMF) was produced from penicillin fermentation fungi mycelium (PFFM) following an acid-heating pretreatment to degrade the residual penicillin. In this study, it was applied into soil as fertilizer to investigate its effects on soil properties, phytotoxicity, microbial community composition, enzyme activities, and growth of snap bean in greenhouse. As the results show, pH, total nitrogen, total phosphorus, total potassium, and organic matter of soil with DMF treatments were generally higher than CON treatment. In addition, the applied DMF did not cause heavy metal and residual drug pollution of the modified soil. The lowest GI values (<0.3) were recorded at DMF8 (36 kg DMF/plat) on the first days after applying the fertilizer, indicating that severe phytotoxicity appeared in the DMF8-modified soil. Results of microbial population and enzyme activities illustrated that DMF was rapidly decomposed and the decomposition process significantly affected microbial growth and enzyme activities. The DMF-modified soil phytotoxicity decreased at the late fertilization time. DMF1 was considered as the optimum amount of DMF dose based on principal component analysis scores. Plant height and plant yield of snap bean were remarkably enhanced with the optimum DMF dose.

  19. Analysis of the DNA-Binding Activities of the Arabidopsis R2R3-MYB Transcription Factor Family by One-Hybrid Experiments in Yeast.

    Directory of Open Access Journals (Sweden)

    Zsolt Kelemen

    Full Text Available The control of growth and development of all living organisms is a complex and dynamic process that requires the harmonious expression of numerous genes. Gene expression is mainly controlled by the activity of sequence-specific DNA binding proteins called transcription factors (TFs. Amongst the various classes of eukaryotic TFs, the MYB superfamily is one of the largest and most diverse, and it has considerably expanded in the plant kingdom. R2R3-MYBs have been extensively studied over the last 15 years. However, DNA-binding specificity has been characterized for only a small subset of these proteins. Therefore, one of the remaining challenges is the exhaustive characterization of the DNA-binding specificity of all R2R3-MYB proteins. In this study, we have developed a library of Arabidopsis thaliana R2R3-MYB open reading frames, whose DNA-binding activities were assayed in vivo (yeast one-hybrid experiments with a pool of selected cis-regulatory elements. Altogether 1904 interactions were assayed leading to the discovery of specific patterns of interactions between the various R2R3-MYB subgroups and their DNA target sequences and to the identification of key features that govern these interactions. The present work provides a comprehensive in vivo analysis of R2R3-MYB binding activities that should help in predicting new DNA motifs and identifying new putative target genes for each member of this very large family of TFs. In a broader perspective, the generated data will help to better understand how TF interact with their target DNA sequences.

  20. Bacterial vaginosis and vaginal yeast, but not vaginal cleansing, increase HIV-1 acquisition in African women

    NARCIS (Netherlands)

    van de Wijgert, Janneke H. H. M.; Morrison, Charles S.; Cornelisse, Peter G. A.; Munjoma, Marshall; Moncada, Jeanne; Awio, Peter; Wang, Jing; van der Pol, Barbara; Chipato, Tsungai; Salata, Robert A.; Padian, Nancy S.

    2008-01-01

    OBJECTIVE: To evaluate interrelationships between bacterial vaginosis (BV), vaginal yeast, vaginal practices (cleansing and drying/tightening), mucosal inflammation, and HIV acquisition. METHODS: A multicenter, prospective, observational cohort study was conducted, enrolling 4531 HIV-negative women

  1. Bactericidal activity of culture fluid components of Lactobacillus fermentum strain 90 TS-4 (21) clone 3, and their capacity to modulate adhesion of Candida albicans yeast-like fungi to vaginal epithelial cells.

    Science.gov (United States)

    Anokhina, I V; Kravtsov, E G; Protsenko, A V; Yashina, N V; Yermolaev, A V; Chesnokova, V L; Dalin, M V

    2007-03-01

    Antagonistic activities of L. fermentum strain 90 TS-4 (21), L. casei ATCC 27216, and L. acidophilus ATCC 4356 and bactericidal activity of lactobacillus culture fluid towards E. coli strain K12, S. aureus, and S. epidermidis test cultures were studied. The bactericidal effect of L. fermentum strain 90 TS-4 (21) clone 3 culture fluid preparation (pH 6.0) on the test cultures was dose-dependent. Adhesion of C. albicans yeast-like fungi to vaginal epitheliocytes was more pronounced for strains isolated from women with asymptomatic infection than for strains isolated from women with manifest forms. L. fermentum strain 90 TS-4 (21) clone 3 culture fluid preparation modulated adhesion of yeast-like fungi only if the fungal strain was initially highly adherent.

  2. The yeast mitogen-activated protein kinase Slt2 is involved in the cellular response to genotoxic stress

    Directory of Open Access Journals (Sweden)

    Soriano-Carot María

    2012-02-01

    Full Text Available Abstract Background The maintenance of genomic integrity is essential for cell viability. Complex signalling pathways (DNA integrity checkpoints mediate the response to genotoxic stresses. Identifying new functions involved in the cellular response to DNA-damage is crucial. The Saccharomyces cerevisiae SLT2 gene encodes a member of the mitogen-activated protein kinase (MAPK cascade whose main function is the maintenance of the cell wall integrity. However, different observations suggest that SLT2 may also have a role related to DNA metabolism. Results This work consisted in a comprehensive study to connect the Slt2 protein to genome integrity maintenance in response to genotoxic stresses. The slt2 mutant strain was hypersensitive to a variety of genotoxic treatments, including incubation with hydroxyurea (HU, methylmetanosulfonate (MMS, phleomycin or UV irradiation. Furthermore, Slt2 was activated by all these treatments, which suggests that Slt2 plays a central role in the cellular response to genotoxic stresses. Activation of Slt2 was not dependent on the DNA integrity checkpoint. For MMS and UV, Slt2 activation required progression through the cell cycle. In contrast, HU also activated Slt2 in nocodazol-arrested cells, which suggests that Slt2 may respond to dNTP pools alterations. However, neither the protein level of the distinct ribonucleotide reductase subunits nor the dNTP pools were affected in a slt2 mutant strain. An analysis of the checkpoint function revealed that Slt2 was not required for either cell cycle arrest or the activation of the Rad53 checkpoint kinase in response to DNA damage. However, slt2 mutant cells showed an elongated bud and partially impaired Swe1 degradation after replicative stress, indicating that Slt2 could contribute, in parallel with Rad53, to bud morphogenesis control after genotoxic stresses. Conclusions Slt2 is activated by several genotoxic treatments and is required to properly cope with DNA damage. Slt

  3. Cr(VI) removal from aqueous solution by dried activated sludge biomass

    International Nuclear Information System (INIS)

    Wu Jun; Zhang Hua; He Pinjing; Yao Qian; Shao Liming

    2010-01-01

    Batch experiments were conducted to remove Cr(VI) from aqueous solution using activated sludge biomass. The effects of acid pretreatment of the biomass, initial pH, biomass and Cr(VI) concentrations on Cr(VI) removal efficiency were investigated. Proton consumption during the removal process and the reducing capacity of sludge biomass were studied. The results show that acid pretreatment could significantly improve Cr(VI) removal efficiency and increase Cr(VI) reducing capacity by 20.4%. Cr(VI) removal was remarkably pH-dependent; lower pH (pH = 1, 2) facilitated Cr(VI) reduction while higher pH (pH = 3, 4) favored sorption of the converted Cr(III). Lower Cr(VI) concentration as well as higher biomass concentration could accelerate Cr(VI) removal. Cr(VI) reduction was not the only reason for proton consumption in the removal process. Pseudo-second-order adsorption kinetic model could successfully simulate Cr(VI) removal except under higher pH conditions (pH = 3, 4).

  4. Flor Yeast: New Perspectives Beyond Wine Aging

    Science.gov (United States)

    Legras, Jean-Luc; Moreno-Garcia, Jaime; Zara, Severino; Zara, Giacomo; Garcia-Martinez, Teresa; Mauricio, Juan C.; Mannazzu, Ilaria; Coi, Anna L.; Bou Zeidan, Marc; Dequin, Sylvie; Moreno, Juan; Budroni, Marilena

    2016-01-01

    The most important dogma in white-wine production is the preservation of the wine aroma and the limitation of the oxidative action of oxygen. In contrast, the aging of Sherry and Sherry-like wines is an aerobic process that depends on the oxidative activity of flor strains of Saccharomyces cerevisiae. Under depletion of nitrogen and fermentable carbon sources, these yeast produce aggregates of floating cells and form an air–liquid biofilm on the wine surface, which is also known as velum or flor. This behavior is due to genetic and metabolic peculiarities that differentiate flor yeast from other wine yeast. This review will focus first on the most updated data obtained through the analysis of flor yeast with -omic tools. Comparative genomics, proteomics, and metabolomics of flor and wine yeast strains are shedding new light on several features of these special yeast, and in particular, they have revealed the extent of proteome remodeling imposed by the biofilm life-style. Finally, new insights in terms of promotion and inhibition of biofilm formation through small molecules, amino acids, and di/tri-peptides, and novel possibilities for the exploitation of biofilm immobilization within a fungal hyphae framework, will be discussed. PMID:27148192

  5. Yeasts are essential for cocoa bean fermentation.

    Science.gov (United States)

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

    2014-03-17

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

  6. Yeast genome sequencing:

    DEFF Research Database (Denmark)

    Piskur, Jure; Langkjær, Rikke Breinhold

    2004-01-01

    For decades, unicellular yeasts have been general models to help understand the eukaryotic cell and also our own biology. Recently, over a dozen yeast genomes have been sequenced, providing the basis to resolve several complex biological questions. Analysis of the novel sequence data has shown...... of closely related species helps in gene annotation and to answer how many genes there really are within the genomes. Analysis of non-coding regions among closely related species has provided an example of how to determine novel gene regulatory sequences, which were previously difficult to analyse because...... they are short and degenerate and occupy different positions. Comparative genomics helps to understand the origin of yeasts and points out crucial molecular events in yeast evolutionary history, such as whole-genome duplication and horizontal gene transfer(s). In addition, the accumulating sequence data provide...

  7. Hydrothermal decomposition of yeast cells for production of proteins and amino acids

    Energy Technology Data Exchange (ETDEWEB)

    Lamoolphak, Wiwat [Department of Chemical Engineering, Faculty of Engineering, Chulalongkorn University, Patumwan, Payathai Road, Bangkok 10330 (Thailand); Goto, Motonobu [Department of Applied Chemistry and Biochemistry, Kumamoto University, Kumamoto 850-8555 (Japan); Sasaki, Mitsuru [Department of Applied Chemistry and Biochemistry, Kumamoto University, Kumamoto 850-8555 (Japan); Suphantharika, Manop [Department of Biotechnology, Faculty of Science, Mahidol University, Rama VI Road, Bangkok 10400 (Thailand); Muangnapoh, Chirakarn [Department of Chemical Engineering, Faculty of Engineering, Chulalongkorn University, Patumwan, Payathai Road, Bangkok 10330 (Thailand); Prommuag, Chattip [Department of Chemical Engineering, Faculty of Engineering, Chulalongkorn University, Patumwan, Payathai Road, Bangkok 10330 (Thailand); Shotipruk, Artiwan [Department of Chemical Engineering, Faculty of Engineering, Chulalongkorn University, Patumwan, Payathai Road, Bangkok 10330 (Thailand)]. E-mail: artiwan.s@chula.ac.th

    2006-10-11

    This study examines hydrothermal decomposition of Baker's yeast cells, used as a model for spent Brewer's yeast waste, into protein and amino acids. The reaction was carried out in a closed batch reactor at various temperatures between 100 and 250 deg. C. The reaction products were separated into water-soluble and solid residue. The results demonstrated that the amount of yeast residue decreased with increasing hydrolysis temperature. After 20 min reaction in water at 250 deg. C, 78% of yeast was decomposed. The highest amount of protein produced was also obtained at this condition and was found to be 0.16 mg/mg dry yeast. The highest amount of amino acids (0.063 mg/mg dry yeast) was found at the lowest temperature tested after 15 min. The hydrolysis product obtained at 200 deg. C was tested as a nutrient source for yeast growth. The growth of yeast cells in the culture medium containing 2 w/v% of this product was comparable to that of the cells grown in the medium containing commercial yeast extract at the same concentration. These results demonstrated the feasibility of using subcritical water to potentially decompose proteinaceous waste such as spent Brewer's yeast while recovering more useful products.

  8. Hydrothermal decomposition of yeast cells for production of proteins and amino acids

    International Nuclear Information System (INIS)

    Lamoolphak, Wiwat; Goto, Motonobu; Sasaki, Mitsuru; Suphantharika, Manop; Muangnapoh, Chirakarn; Prommuag, Chattip; Shotipruk, Artiwan

    2006-01-01

    This study examines hydrothermal decomposition of Baker's yeast cells, used as a model for spent Brewer's yeast waste, into protein and amino acids. The reaction was carried out in a closed batch reactor at various temperatures between 100 and 250 deg. C. The reaction products were separated into water-soluble and solid residue. The results demonstrated that the amount of yeast residue decreased with increasing hydrolysis temperature. After 20 min reaction in water at 250 deg. C, 78% of yeast was decomposed. The highest amount of protein produced was also obtained at this condition and was found to be 0.16 mg/mg dry yeast. The highest amount of amino acids (0.063 mg/mg dry yeast) was found at the lowest temperature tested after 15 min. The hydrolysis product obtained at 200 deg. C was tested as a nutrient source for yeast growth. The growth of yeast cells in the culture medium containing 2 w/v% of this product was comparable to that of the cells grown in the medium containing commercial yeast extract at the same concentration. These results demonstrated the feasibility of using subcritical water to potentially decompose proteinaceous waste such as spent Brewer's yeast while recovering more useful products

  9. Tenderness, pH and Water Activity (Aw of Spices Dried Meat on Various Concentrate of Ginger Extract (Zingiber Officinale Roscoe and Different Soaking Time

    Directory of Open Access Journals (Sweden)

    Akhadiyah Afrila

    2012-09-01

    Full Text Available The objectives of current research were to find out the concentrate of Ginger extract (Zingiber officinale Roscoe and different soaking time of to tenderness, pH, and water activity (Aw, microbial count and sensory evaluation of spices dried meat. The result showed that higher the ginger extract (Zingiber officinale Roscoe concentrate and longer the soaking time, it would give more tenderness, pH, and water activity (Aw to spices dried meat with 15% ginger extract (Zingiber officinale Roscoe extract and 20 minutes length of soaking time. Key Words : Dendeng, ginger, soaking time, tenderness, pH and Aw

  10. Dry Etching

    DEFF Research Database (Denmark)

    Stamate, Eugen; Yeom, Geun Young

    2016-01-01

    generation) to 2,200 × 2,500 mm (eighth generation), and the substrate size is expected to increase further within a few years. This chapter aims to present relevant details on dry etching including the phenomenology, materials to be etched with the different recipes, plasma sources fulfilling the dry...

  11. Effects of Freeze-dried Mulberry on Antioxidant Activities and Fermented Characteristics of Yogurt during Refrigerated Storage

    Science.gov (United States)

    2015-01-01

    This study investigated the effect of added freeze-dried mulberry fruit juice (FDMJ) (1, 3 and 5%) on the antioxidant activity and fermented characteristic of yogurt during refrigerated storage. A decrease in pH of yogurt and increase in acidity was observed during fermentation. The yogurts with FDMJ exhibited faster rate of pH reduction than control. Initial lactic acid bacteria count of yogurt was 6.49-6.94 Log CFU/g and increased above 9 Log CFU/g in control and 1% in FDMJ yogurt for 24 h. The total polyphenol and anthocyanin content of FDMJ yogurt was higher than that of control due to the presence of phytochemical contents in mulberry. Moreover, antioxidant activity such as DPPH and reducing power was highest 5% FDMJ yogurt. During cold storage, pH decreased or remained constant in all yogurts with values ranging from 4.08 to 4.78 units. In sensory evaluation, the score of 1% FDMJ yogurt was ranked higher when compared with other yogurts. It is proposed that mulberry fruit juice powder can be used to improve sensory evaluation and enhance functionality of yogurt. PMID:26877641

  12. Stability of Antiradical Activity of Protein Extracts and Hydrolysates from Dry-Cured Pork Loins with Probiotic Strains of LAB

    Directory of Open Access Journals (Sweden)

    Paulina Kęska

    2018-04-01

    Full Text Available The application of starter cultures to improve quality and safety has become a very common practice in the meat industry. Probiotic strains of lactic acid bacteria (LAB can also bring health benefits by releasing bioactive peptides. The aim of this work was to evaluate the stability of antiradical activity of protein extracts from LAB-inoculated dry-cured pork loins during long-term aging and evaluate their hydrolysates after simulated gastrointestinal digestion. Analyses of hydrolysates by using liquid chromatography-tandem mass spectrometry (LC-MS/MS were strengthened with in silico analysis. The highest antiradical activity of the protein extracts was observed after 180 days of aging. The influence of the strain used (LOCK, BAUER, or BB12 on the inactivation ability of ABTS radicals varied during long-term aging. The IC50 values indicated the higher antiradical properties of salt-soluble (SSF compared to water-soluble fraction (WSF of proteins. The peptides generated by in vitro digestion have MW between 700 and 4232 Da and their length ranged from 5 to 47 amino acids in a sequence where Leu, Pro, Lys, Glu, and His had the largest share. This study demonstrates that the degradation of pork muscle proteins during gastrointestinal digestion may give rise to a wide variety of peptides with antiradical properties.

  13. Effects of Freeze-dried Mulberry on Antioxidant Activities and Fermented Characteristics of Yogurt during Refrigerated Storage.

    Science.gov (United States)

    Sung, Jung-Min; Kim, Young-Boong; Kum, Jun-Seok; Choi, Yun-Sang; Seo, Dong-Ho; Choi, Hyun-Wook; Park, Jong-Dae

    2015-01-01

    This study investigated the effect of added freeze-dried mulberry fruit juice (FDMJ) (1, 3 and 5%) on the antioxidant activity and fermented characteristic of yogurt during refrigerated storage. A decrease in pH of yogurt and increase in acidity was observed during fermentation. The yogurts with FDMJ exhibited faster rate of pH reduction than control. Initial lactic acid bacteria count of yogurt was 6.49-6.94 Log CFU/g and increased above 9 Log CFU/g in control and 1% in FDMJ yogurt for 24 h. The total polyphenol and anthocyanin content of FDMJ yogurt was higher than that of control due to the presence of phytochemical contents in mulberry. Moreover, antioxidant activity such as DPPH and reducing power was highest 5% FDMJ yogurt. During cold storage, pH decreased or remained constant in all yogurts with values ranging from 4.08 to 4.78 units. In sensory evaluation, the score of 1% FDMJ yogurt was ranked higher when compared with other yogurts. It is proposed that mulberry fruit juice powder can be used to improve sensory evaluation and enhance functionality of yogurt.

  14. Methods for Determination of α-Glycosidase, β-Glycosidase, and α-Galactosidase Activities in Dried Blood Spot Samples.

    Science.gov (United States)

    Sozmen, Eser Yıldırım; Sezer, Ebru Demirel

    2017-01-01

    The lysosomal storage diseases (LDSs) are a heterogeneous group of inherited genetic disorders caused by defects of lysosomal proteins. The accumulation of undigested substrates from different catabolic pathways leads to cellular dysfunction. LSDs generally presents during early childhood and have a devastating impact on the families and on public health. Over the years, approaches for treatment of some LSDs have been developed with different strategies. Increasing availability of treatments of these diseases has accelerated the development of new methods and techniques for rapid diagnosis in patients with clinical indication.The use of dried blood spot (DBS) test has been proposed as a first tier test to identify patients with Gaucher, Pompe, and Fabry diseases. DBS usage is advantageous for the purpose of screening as it is non-invasive, sensitive, has low-cost and fast turnaround time compared to measurements in leucocyte and/or fibroblast culture. This chapter focuses on the activity measurement of three lysosomal enzymes (α-glucosidase, β-glucosidase, and α galactosidase) in DBS samples by using fluorescent substrates and by the LC-MS/MS (liquid chromatography-mass spectrometry) method. All steps of the methods, from preparation of the solutions to calculation of the enzyme activity, will be explained in detail.

  15. Silver nanoparticle production by the fungus Fusarium oxysporum: nanoparticle characterisation and analysis of antifungal activity against pathogenic yeasts

    Directory of Open Access Journals (Sweden)

    Kelly Ishida

    2014-04-01

    Full Text Available The microbial synthesis of nanoparticles is a green chemistry approach that combines nanotechnology and microbial biotechnology. The aim of this study was to obtain silver nanoparticles (SNPs using aqueous extract from the filamentous fungus Fusarium oxysporum as an alternative to chemical procedures and to evaluate its antifungal activity. SNPs production increased in a concentration-dependent way up to 1 mM silver nitrate until 30 days of reaction. Monodispersed and spherical SNPs were predominantly produced. After 60 days, it was possible to observe degenerated SNPs with in additional needle morphology. The SNPs showed a high antifungal activity against Candida and Cryptococcus , with minimum inhibitory concentration values ≤ 1.68 µg/mL for both genera. Morphological alterations of Cryptococcus neoformans treated with SNPs were observed such as disruption of the cell wall and cytoplasmic membrane and lost of the cytoplasm content. This work revealed that SNPs can be easily produced by F. oxysporum aqueous extracts and may be a feasible, low-cost, environmentally friendly method for generating stable and uniformly sized SNPs. Finally, we have demonstrated that these SNPs are active against pathogenic fungi, such as Candida and Cryptococcus .

  16. Simultaneous wastewater treatment and biogas production using integrated anaerobic baffled reactor granular activated carbon from baker's yeast wastewater.

    Science.gov (United States)

    Pirsaheb, Meghdad; Mohamadi, Samira; Rahmatabadi, Sama; Hossini, Hooshyar; Motteran, Fabrício

    2017-08-30

    In this study, simultaneous degradation of organic matter and color removal from food processing industries wastewater using an integrated anaerobic baffled reactor granular activated carbon (IABRGAC) was investigated. Theretofore, effective parameters such as hydraulic retention time (HRT) and granular activated carbon (GAC) filling ratio were studied. The bioreactor was operated at 3, 4 and 5 d of HRT and GAC filling ratio of 20%, 35% and 50%. To analyze and optimize the independent operating variables, response surface methodology was applied. Operating condition was optimized for HRT (4 d) and GAC filling ratio (50%). Better COD (94.6%) and BOD (93.7%) removal efficiency occurred with loading COD of 15,000 mg/L, with diminished wastewater color around 54% and turbidity to 54 NTU. In addition, methane production, methane yielding rate (Y m ) and specific methanogenic activity (SMA) test in an integrated system were investigated. The system IABRGAC was able to generate a volumetric rate about 0.31 and 0.44 L/g COD removed d at the experimental condition. The Y m was between 0.31 and 0.44 L/g COD removed .d and SMA was between 0.13 and 0.38 g COD/g volatile suspended solid. Based on results it can be concluded that the IABRGAC to be a successful pretreatment for highstrength wastewater before discharging the final effluent to sewerage and aerobic treating processes.

  17. Comparative study of DL-selenomethionine vs sodium selenite and seleno-yeast on antioxidant activity and selenium status in laying hens.

    Science.gov (United States)

    Jing, C L; Dong, X F; Wang, Z M; Liu, S; Tong, J M

    2015-05-01

    The aim of this study was to compare the effect of DL-selenomethionine (SM) with 2 routinely used Se sources, sodium selenite (SS) and seleno-yeast (SY), on relative bioavailability based on antioxidant activity and tissue Se content. Six hundred thirty 131-day-old brown laying hens were randomly assigned to 7 treatments for 168 d (24 wks) with 6 replicates of 15 hens per replicate. The SS and SY animals were supplemented a cornmeal and soybean diet that supplied a total Se 0.3 mg/kg whereas SM was added at 4 different levels to the total Se at 0.1, 0.3, 0.5 and 0.7 mg/kg. All hens fed the Se-supplemented diet showed higher glutathione peroxidase (GSH-Px) activity (P < 0.01), higher superoxide dismutase (SOD) activity (P < 0.05), lower malondialdehyde (MDA) content (P < 0.05) in plasma, and greater Se contents in egg yolks, albumen, leg muscle, breast muscle, liver, and plasma compared with those fed the control diet (P < 0.01). The organic sources (SY and SM) exhibited a greater ability to increase the GSH-Px activity (P < 0.01) and Se content in albumen (P < 0.01), leg, and breast muscles (P = 0.0099 and P = 0.0014, respectively) than the SS that was added at 0.3 mg Se/kg. The higher SM added levels increased the GSH-Px activity until the dose of 0.5mg Se/kg (P < 0.01).The greater Se concentrations in albumen, muscle and liver appeared in the higher SM-added level, as well as above the dose of 0.1 mg Se/kg (P < 0.01). In addition, hens fed the diet with SM accumulated more Se in albumen, leg, and breast muscle than those fed diets with SY (P < 0.05). These results confirmed the higher ability of organic Se sources to increase the antioxidant activity and Se deposition in egg albumen, leg, and breast muscles compared with SS, and demonstrated a significantly better efficiency of SM compared with SY for albumen and muscle Se enrichment. © 2015 Poultry Science Association Inc.

  18. Caracterização química do autolisado de levedura de alambique e avaliação da aceitabilidade do pão de queijo adicionado do autolisado desidratado Chemical characterization of yeast autolysate and assessment of the acceptability of cheese buns containing dried autolysate

    Directory of Open Access Journals (Sweden)

    Giselle Rossi Vasconcelos Ramos

    2011-06-01

    atrativa.OBJECTIVE: This study aimed to study the properties of yeast (Saccharomyces cerevisiae autolysate obtained from pot still rum, including centesimal composition, amino acid profile and microbiological analysis, and perform a sensory analysis of cheese buns (also known as Brazilian cheese bread or rolls enriched with dried autolysate. METHODS: Autolysate was obtained by rinsing and autolyzing the biomass and dried on a tray dryer at 70º. Its composition was then determined (fat, protein, total fiber, soluble fiber, insoluble fiber, ash and amino acid contents followed by microbiological analysis. Finally, cheese buns enriched with dried autolysate were submitted to sensory analysis using the hedonic scale and attitude test. RESULTS: Dried autolysate contained 1.2% fats; 24.7% proteins; 51.3% total fiber, where 2.4% was soluble and 48.9% was insoluble; and 6.2% ash. According to microbiological analysis, the product complied with the microbiological limits established by the Agência Nacional de Vigilância Sanitária. Amino acid profile showed that histidine and methionine-cystine levels were low. Sensory analysis indicated good acceptance of the cheese buns. Only their color and appearance received low scores. Most participants reported liking the cheese buns and willingness to buy them on occasion. CONCLUSION: The protein and amino acid levels found in pot still rum were lower than those reported in the literature for breweries and ethanol distilleries. Dried yeast was microbiologically suitable for human consumption. The low grades given to the appearance of the cheese buns were probably due to their unappealing dark color, as opposed to the usual pale yellow color. Future studies could suggest the addition of dried yeast to products whose visual appeal will not be as affected.

  19. Metabolic regulation of yeast

    Science.gov (United States)

    Fiechter, A.

    1982-12-01

    Metabolic regulation which is based on endogeneous and exogeneous process variables which may act constantly or time dependently on the living cell is discussed. The observed phenomena of the regulation are the result of physical, chemical, and biological parameters. These parameters are identified. Ethanol is accumulated as an intermediate product and the synthesis of biomass is reduced. This regulatory effect of glucose is used for the aerobic production of ethanol. Very high production rates are thereby obtained. Understanding of the regulation mechanism of the glucose effect has improved. In addition to catabolite repression, several other mechanisms of enzyme regulation have been described, that are mostly governed by exogeneous factors. Glucose also affects the control of respiration in a third class of yeasts which are unable to make use of ethanol as a substrate for growth. This is due to the lack of any anaplerotic activity. As a consequence, diauxic growth behavior is reduced to a one-stage growth with a drastically reduced cell yield. The pulse chemostat technique, a systematic approach for medium design is developed and medium supplements that are essential for metabolic control are identified.

  20. Inulin sugar glasses preserve the structural integrity and biological activity of influenza virosomes during freeze-drying and storage

    NARCIS (Netherlands)

    de Jonge, Jørgen; Amorij, Jean-Pierre; Hinrichs, Wouter L.J.; Wilschut, Jan; Huckriede, Anke; Frijlink, Henderik W.

    Influenza virosomes are reconstituted influenza virus envelopes that may be used as vaccines or as carrier systems for cellular delivery of therapeutic molecules. Here we present a procedure to generate influenza virosomes as a stable dry-powder formulation by freeze-drying (lyophilization) using an

  1. The effect of dry corn gluten feed on chewing activities and rumen parameters in lactating dairy cows

    Directory of Open Access Journals (Sweden)

    Ibrahim Ismet Turkmen

    2010-01-01

    Full Text Available The objectives of this research were to evaluate the effects of increasing levels of dry corn gluten feed (DCGF on dry matter intake (DMI, chewing activity, and rumen fermentation when used to replace a portion of corn silage in diets for lactating Holstein cows. Eight lactating Holstein primiparous cows averaging 98±20 d in milk and weighing 515±20 kg were randomly assigned in a 4x4 Latin square design with 4 week periods. Dietary treatments were 1 a control diets (C of 50% forage (corn silage and wheat straw, 35%, 15% DM basis, respectively, 2 a low DCGF diet (L-DCGF in which 10% of the same corn silage was replaced by DCGF, 3 a medium DCGF diet (M-DCGF in which 18% of the same corn silage was replaced by DCGF, and 4 a high DCGF diet (H-DCGF in which 25% of the same corn silage was replaced by DCGF. The proportion of particles retained on the 19.0 mm screen and physical effectiveness factor of the HDCGF was lower (P<0.05 than in the other groups. Increasing the level of DCGF did not change DMI. Cows fed the C diet spent significantly more time ruminating and chewing per day compared with the MDCGF and H-DCGF diets (483.88, 435.63, 431.25 min/d, P<0.05; and 818.38, 753.00, 745.75 min/d respectively, P<0.05. Cows fed the C diet had ruminal pH values higher than the cows fed the M-DCGF and H-DCGF diets (6.02, 5.95, and 5.91, P<0.05. The total volatile fatty acid and propionate levels of H-DCGF fed cows were higher than the control (P<0.05. The changes in acetate (A and propionate (P concentrations resulted in a decrease in A/P ratio, when corn silage was replaced by DCGF, which led to a reduction in the particle size of the diets (P<0.05. It was concluded that when ratio 18 and 25% DCGF were substituted for corn silage, rumination time, chewing activities and ruminal pH are negatively affected. The optimum level for the addition of DCGF was found to be below 18% of the diet for a healthy rumen and a chewing behaviour in dairy cows.

  2. Nonlinear Dielectric Properties of Yeast Cells Cultured in Different Environmental Conditions

    Science.gov (United States)

    Kawanishi, Gomon; Fukuda, Naoki; Muraji, Masafumi

    The harmonics of the electric current through yeast suspensions, the nonlinear dielectric properties of yeast cells, have particular patterns according to the biological activity of the cells and the measurement of these patterns is a technique for determining the activity of living cells. The concentration of glucose and oxygen in yeast culture medium influences the manifestation of fermentation or respiration of yeast cells. Measurements were made with yeast cells (Saccharomyces cerevisiae) cultured aerobically and anaerobically in sufficient glucose concentration, aerobic fermentation and anaerobic fermentation, and aerobically in limited glucose concentration, respiration. The results showed that the harmonics were barely apparent for yeast cells in aerobic fermentation and respiratory; however, cells in the anaerobic fermentation displayed substantial third and fifth harmonics. We can say that environmental condition affects the yeast cells' nonlinear properties, from another viewpoint, the measurements of the nonlinear properties are available to determine the activity of yeast cells adjusted to the conditions of their cultivation.

  3. Estimating the effect of fermentation yeast on distillers grains protein

    Science.gov (United States)

    Distillers dried grains with solubles (DDGS) is the key co-product of bio-ethanol production from grains. Major factors affecting its quality and market values include protein quantity (concentration) and quality (amino acid composition). Yet, the effect of fermentation yeast on DDGS quality has no...

  4. Effects of dietary yeastβ-glucan on nutrient digestibility and serum proifles in pre-ruminant Holstein calves

    Institute of Scientific and Technical Information of China (English)

    MA Tao; TU Yan; ZHANG Nai-feng; GUO Jiang-peng; DENG Kai-dong; ZHOU Yi; YUN Qiang; DIAO Qi-yu

    2015-01-01

    This study aimed to investigate the effects of dietary supplementation of yeastβ-glucan on the nutrient digestibility and serum proifles in pre-ruminant Holstein calves. Forty-two neonatal Holstein calves ((39.6±4.2) kg) were randomly al otted to six groups, and each was offered one of the fol owing diets:a basal diet (control) or the basal diet supplemented with 25, 50, 75, 100 or 200 mg of yeastβ-glucan kg–1 feed (dry matter basis). The basal diet consisted of a milk replacer and a starter feed. The trial lasted for 56 d. Two digestibility trials were conducted from d 14 to 20 and from d 42 to 48. Blood samples were col ected on d 0, 14, 28 and 42 for serum proifle analyses. On d 56, three calves from each group were slaughtered, and intestinal samples were col ected to assess the vil ous height, crypt depth and mucosal thickness. Although feed intake was not affected by dietary treatment (P>0.05), the average daily gain (ADG) and gain-to-feed ratios were higher (P0.05). Compared with the control group, supplementation of yeastβ-glucan decreased (P0.05). The supplementation of yeastβ-glucan stimu-lated the enzymatic activity of alkaline phosphatase (ALP) (P<0.05) compared with the control group. The lysozyme (LYZ) concentration increased quadratical y (P<0.05) with increasing yeastβ-glucan levels. The results suggested that dietary supplementation of yeastβ-glucan at 75 mg kg–1 feed improved nutrient digestibility, enhanced immunity by increasing the immunoglobulin concentration and stimulating ALP, and exerted no adverse effects on metabolism in pre-ruminant calves.

  5. Temperature-sensitive defects of the GSP1gene, yeast Ran homologue, activate the Tel1-dependent pathway

    International Nuclear Information System (INIS)

    Hayashi, Naoyuki; Murakami, Seishi; Tsurusaki, Susumu; Nagaura, Zen-ichiro; Oki, Masaya; Nishitani, Hideo; Kobayashi, Masahiko; Shimizu, Hiroko; Yamamoto, Ken-ichi; Nishimoto, Takeharu

    2007-01-01

    RanGTPase is involved in many cellular processes. It functions in nuclear-cytosolic transport and centrosome formation. Ran also localizes to chromatin as RCC1 does, its guanine nucleotide exchange factor, but Ran's function on chromatin is not known. We found that gsp1, a temperature-sensitive mutant of GSP1, a Saccharomyces cerevisiae Ran homologue, suppressed the hydroxyurea (HU) and ultra violet (UV) sensitivities of the mec1 mutant. In UV-irradiated mec1 gsp1 cells, Rad53 was phosphorylated despite the lack of Mec1. This suppression depended on the TEL1 gene, given that the triple mutant, mec1 gsp1 tel1, was unable to grow. The gsp1 mutations also suppressed the HU sensitivity of the rad9 mutant in a Tel1-dependent manner, but not the HU sensitivity of the rad53 mutant. These results indicated that Rad53 was activated by the Tel1 pathway in mec1 gsp1 cells, suggesting that Gsp1 helps regulate the role switching the ATM family kinases Mec1 and Tel1

  6. Antimicrobial activity of rosemary-pepper essential oil and barbatimao dry crude extract against bacteria isolated from milk

    Directory of Open Access Journals (Sweden)

    João Paulo Ramos Costa

    2011-12-01

    Full Text Available The aim of this study was to evaluate the in vitro antimicrobial activity of Lippia sidoides essential oil (LsEO, popularly known as “rosemary-pepper”, and the Stryphnodendron adstringens dry crude extract (SaDCE, or “barbatimao”, against bacteria isolated from total milk flock, from small farms of northern Minas Gerais state. SaDCE was obtained from the peel of the vegetable through static distillation in ethanol 99.9% during eight days. LsEO was obtained through hydro-distillation of its fresh leaves. The bacteria Escherichia coli and Staphylococcus aureus isolated from milk underwent the test of disk-diffusion and minimum bacterial concentration (MBC, using concentrations of 320, 160, 80, 40, 20 and 0μl/mL of LsEO and 400, 200, 100, 50, 25 and 0mg/mL of SaDCE. All bacteria were sensitive to the vegetable extracts, except the Escherichia coli which was not inhibited by any test when SaDCE was used.

  7. Economic feasibility of invesment alternatives for reducing torula yeast' production cost

    International Nuclear Information System (INIS)

    Torres Fernández, Alfredo; Díaz de los Ríos, Manuel; Saura Laria, Gustavo

    2016-01-01

    The prices of ammonium salts which are used in the torula yeast production technology are very high nowadays. In the other hand, this technology has very high energy costs which are consumed by blowers in fermentation, separators machines and in the concentration and drying of yeast. In this paper, different technical alternatives are analyzed for reducing the production cost of torula yeast, through changes in production inputs, electric motors and the replacement of a portion of the fuel used for drying by biogas. Then, the economic feasibility in both currencies is evaluated for practical application. (author)

  8. ECONOMIC FEASIBILITY OF INVESMENT ALTERNATIVES FOR REDUCING TORULA YEAST' PRODUCTION COST

    Directory of Open Access Journals (Sweden)

    Alfredo Torres Fernández

    2016-01-01

    Full Text Available The prices of ammonium salts which are used in the torula yeast production technology are very high nowadays. In the other hand, this technology has very high energy costs which are consumed by blowers in fermentation, separators machines and in the concentration and drying of yeast. In this paper, different technical alternatives are analyzed for reducing the production cost of torula yeast, through changes in production inputs, electric motors and the replacement of a portion of the fuel used for drying by biogas. Then, the economic feasibility in both currencies is evaluated for practical application.

  9. Interaction of Yna1 and Yna2 Is Required for Nuclear Accumulation and Transcriptional Activation of the Nitrate Assimilation Pathway in the Yeast Hansenula polymorpha.

    Science.gov (United States)

    Silvestrini, Lucia; Rossi, Beatrice; Gallmetzer, Andreas; Mathieu, Martine; Scazzocchio, Claudio; Berardi, Enrico; Strauss, Joseph

    2015-01-01

    A few yeasts, including Hansenula polymorpha are able to assimilate nitrate and use it as nitrogen source. The genes necessary for nitrate assimilation are organised in this organism as a cluster comprising those encoding nitrate reductase (YNR1), nitrite reductase (YNI1), a high affinity transporter (YNT1), as well as the two pathway specific Zn(II)2Cys2 transcriptional activators (YNA1, YNA2). Yna1p and Yna2p mediate induction of the system and here we show that their functions are interdependent. Yna1p activates YNA2 as well as its own (YNA1) transcription thus forming a nitrate-dependent autoactivation loop. Using a split-YFP approach we demonstrate here that Yna1p and Yna2p form a heterodimer independently of the inducer and despite both Yna1p and Yna2p can occupy the target promoter as mono- or homodimer individually, these proteins are transcriptionally incompetent. Subsequently, the transcription factors target genes containing a conserved DNA motif (termed nitrate-UAS) determined in this work by in vitro and in vivo protein-DNA interaction studies. These events lead to a rearrangement of the chromatin landscape on the target promoters and are associated with the onset of transcription of these target genes. In contrast to other fungi and plants, in which nuclear accumulation of the pathway-specific transcription factors only occur in the presence of nitrate, Yna1p and Yna2p are constitutively nuclear in H. polymorpha. Yna2p is needed for this nuclear accumulation and Yna1p is incapable of strictly positioning in the nucleus without Yna2p. In vivo DNA footprinting and ChIP analyses revealed that the permanently nuclear Yna1p/Yna2p heterodimer only binds to the nitrate-UAS when the inducer is present. The nitrate-dependent up-regulation of one partner protein in the heterodimeric complex is functionally similar to the nitrate-dependent activation of nuclear accumulation in other systems.

  10. Chromosomal Aneuploidy Improves the Brewing Characteristics of Sake Yeast.

    Science.gov (United States)

    Kadowaki, Masafumi; Fujimaru, Yuki; Taguchi, Seiga; Ferdouse, Jannatul; Sawada, Kazutaka; Kimura, Yuta; Terasawa, Yohei; Agrimi, Gennaro; Anai, Toyoaki; Noguchi, Hideki; Toyoda, Atsushi; Fujiyama, Asao; Akao, Takeshi; Kitagaki, Hiroshi

    2017-12-15

    The effect of chromosomal aneuploidy on the brewing characteristics of brewery yeasts has not been studied. Here we report that chromosomal aneuploidy in sake brewery yeast ( Saccharomyces cerevisiae ) leads to the development of favorable brewing characteristics. We found that pyruvate-underproducing sake yeast, which produces less off-flavor diacetyl, is aneuploid and trisomic for chromosomes XI and XIV. To confirm that this phenotype is due to aneuploidy, we obtained 45 haploids with various chromosomal additions and investigated their brewing profiles. A greater number of chromosomes correlated with a decrease in pyruvate production. Especially, sake yeast haploids with extra chromosomes in addition to chromosome XI produced less pyruvate than euploids. Mitochondrion-related metabolites and intracellular oxygen species in chromosome XI aneuploids were higher than those in euploids, and this effect was canceled in their "petite" strains, suggesting that an increase in chromosomes upregulated mitochondrial activity and decreased pyruvate levels. These findings suggested that an increase in chromosome number, including chromosome XI, in sake yeast haploids leads to pyruvate underproduction through the augmentation of mitochondrial activity. This is the first report proposing that aneuploidy in brewery yeasts improves their brewing profile. IMPORTANCE Chromosomal aneuploidy has not been evaluated in development of sake brewing yeast strains. This study shows the relationship between chromosomal aneuploidy and brewing characteristics of brewery yeast strains. High concentrations of pyruvate during sake storage give rise to α-acetolactate and, in turn, to high concentrations of diacetyl, which is considered an off-flavor. It was demonstrated that pyruvate-underproducing sake yeast is trisomic for chromosome XI and XIV. Furthermore, sake yeast haploids with extra chromosomes produced reduced levels of pyruvate and showed metabolic processes characteristic of

  11. Biocontrol activity of four non- and low-fermenting yeast strains against Aspergillus carbonarius and their ability to remove ochratoxin A from grape juice.

    Science.gov (United States)

    Fiori, Stefano; Urgeghe, Pietro Paolo; Hammami, Walid; Razzu, Salvatorico; Jaoua, Samir; Migheli, Quirico

    2014-10-17

    Aspergillus spp. infection of grape may lead to ochratoxin A (OTA) contamination in processed beverages such as wine and grape juice. The aim of the current study was to evaluate the biocontrol potential of two non-fermenting (Cyberlindnera jadinii 273 and Candida friedrichii 778) and two low-fermenting (Candida intermedia 235 and Lachancea thermotolerans 751) yeast strains against the pathogenic fungus and OTA-producer Aspergillus carbonarius, and their ability to remove OTA from grape juice. Two strains, 235 and 751, showed a significant ability to inhibit A. carbonarius both on grape berries and in in vitro experiments. Neither their filtrate nor their autoclaved filtrate culture broth was able to prevent consistently pathogen growth. Volatile organic compounds (VOCs) produced by all four selected yeasts were likely able to consistently prevent pathogen sporulation in vitro. VOCs produced by the non-fermenting strain 778 also significantly reduced A. carbonarius vegetative growth. Three yeast strains (235, 751, and 778) efficiently adsorbed artificially spiked OTA from grape juice, while autoclaving treatment improved OTA adsorption capacity by all the four tested strains. Biological control of A. carbonarius and OTA-decontamination using yeast is proposed as an approach to meet the Islamic dietary laws concerning the absence of alcohol in halal beverages. Copyright © 2014 The Authors. Published by Elsevier B.V. All rights reserved.

  12. Vaginal yeast infections while deployed in Southwest/Central Asia, active component females, U.S. Armed Forces, 2008-2013.

    Science.gov (United States)

    2014-08-01

    In field settings, female service members may not have adequate access to bathrooms, showers, laundry, or sanitary products necessary to maintain adequate feminine hygiene; therefore, service women may be at risk for vaginal yeast infections while deployed. During the 6-year surveillance period, nearly 3,000 U.S. military service women were diagnosed with at least one clinically significant yeast infection while supporting combat operations in Southwest/Central Asia. The crude overall incidence rate was 35.1 per 1,000 person-years (p-yrs). Overall incidence rates were higher among black, non-Hispanic service women, and among those in the Army and Air Force, in enlisted grades, and in communications/intelligence and motor transport occupations. The yearly rate of yeast infections was relatively stable from 2008 through 2010, then decreased in 2011 through 2013. Prior to deploying to austere operational settings, female service members should be provided practical and useful information, realistic training, and material support to decrease the risk of acquiring and increase the effectiveness of treating clinically and military operationally significant yeast infections.

  13. Identification of conserved prolyl residue important for transport activity and the substrate specificity range of yeast plasma membrane Na(+)/H(+) antiporters

    Czech Academy of Sciences Publication Activity Database

    Zimmermannová, Olga; Zavřel, Martin; Sychrová, Hana

    2005-01-01

    Roč. 280, č. 34 (2005), s. 30638-30647 ISSN 0021-9258 R&D Projects: GA ČR(CZ) GP204/02/D092 Institutional research plan: CEZ:AV0Z5011922 Keywords : yeast * Na+/H+ antiporter * substrate specificity Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 5.854, year: 2005

  14. Overexpression of the genes PDC1 and ADH1 activates glycerol conversion to ethanol in the thermotolerant yeast Ogataea (Hansenula) polymorpha.

    Science.gov (United States)

    Kata, Iwona; Semkiv, Marta V; Ruchala, Justyna; Dmytruk, Kostyantyn V; Sibirny, Andriy A

    2016-08-01

    Conversion of byproduct from biodiesel production glycerol to high-value compounds is of great importance. Ethanol is considered a promising product of glycerol bioconversion. The methylotrophic thermotolerant yeast Ogataea (Hansenula) polymorpha is of great interest for this purpose as the glycerol byproduct contains methanol and heavy metals as contaminants, and this yeast utilizes methanol and is relatively resistant to heavy metals. Besides, O. polymorpha shows robust growth on glycerol and produces ethanol from various carbon sources. The thermotolerance of this yeast is an additional advantage, allowing increased fermentation temperature to 45-48 °C, leading to increased rate of the fermentation process and a fall in the cost of distillation. The wild-type strain of O. polymorpha produces insignificant amounts of ethanol from glycerol (0.8 g/l). Overexpression of PDC1 coding for pyruvate decarboxylase enhanced ethanol production up to 3.1 g/l, whereas simultaneous overexpression of PDC1 and ADH1 (coding for alcohol dehydrogenase) led to further increase in ethanol production from glycerol. Moreover, the increased temperature of fermentation up to 45 °C stimulated the production of ethanol from glycerol used as the only carbon source up to 5.0 g/l, which exceeds the data obtained by methylotrophic yeast strains reported so far. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  15. Inhibition of ochratoxigenic moulds by Debaryomyces hansenii strains for biopreservation of dry-cured meat products

    DEFF Research Database (Denmark)

    Andrade, Maria J.; Thorsen, Line; Rodríguez, Alicia

    2014-01-01

    mould growth and OTA accumulation in dry-cured meat products. The inoculation of D. hansenii should be made at the beginning of processing (at the end of post salting) when the a(w) of the product is still high (near 0.94). This action in addition to application of appropriate hygienic actions......The ability of the osmotolerant yeast Debaryomyces hansenii to inhibit Penicillium nordicum, the most common ochratoxigenic mould encountered in dry-cured meat products, was evaluated. The antagonistic effect of ten D. hansenii strains isolated from dry-cured ham was screened in vitro using malt...... extract media and meat extract peptone media with the water activity (a(w)) adjusted to 0.97 and 0.90. A significant inhibition of the two tested P. nordicum strains by D. hansenii cells and cell-free supernatants was observed. At 0.97 a(w), increasing D. hansenii inoculum concentrations significantly...

  16. Pollutant removal-oriented yeast biomass production from high-organic-strength industrial wastewater: A review

    International Nuclear Information System (INIS)

    Yang, Min; Zheng, Shaokui

    2014-01-01

    Microbial single-cell-protein (SCP) production from high-organic-strength industrial wastewaters is considered an attractive method for both wastewater purification and resource utilization. In the last two decades, pollutant removal-oriented yeast SCP production processes, i.e., yeast treatment processes, have attracted a great deal of attention from a variety of research groups worldwide. Different from conventional SCP production processes, yeast treatment processes are characterized by higher pollutant removal rates, lower production costs, highly adaptive yeast isolates from nature, no excess nutrient supplements, and are performed under non-sterile conditions. Furthermore, yeast treatment processes are similar to bacteria-dominated conventional activated sludge processes, which offer more choices for yeast SCP production and industrial wastewater treatment. This review discusses why highly adaptive yeast species isolated from nature are used in the yeast treatment process rather than commercial SCP producers. It also describes the application of yeast treatment processes for treating high-carboxyhydrate, oil-rich and high-salinity industrial wastewater, focusing primarily on high-strength biodegradable organic substances, which usually account for the major fraction of biochemical oxygen demand. Also discussed is the biodegradation of xenobiotics, such as color (including dye and pigment) and toxic substances (including phenols, chlorophenols, polycyclic aromatic hydrocarbons, etc.), present in industrial wastewater. Based on molecular information of yeast community structures and their regulation in yeast treatment systems, we also discuss how to maintain efficient yeast species in yeast biomass and how to control bacterial and mold proliferation in yeast treatment systems. - Highlights: • Pollutant removal-oriented yeast SCP production processes offer more choices. • Highly adaptive yeast isolates replace commercial SCP producers. • Yeasts degrade

  17. Genetics of Yeasts

    Science.gov (United States)

    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.

  18. Dry cell battery poisoning

    Science.gov (United States)

    Batteries - dry cell ... Acidic dry cell batteries contain: Manganese dioxide Ammonium chloride Alkaline dry cell batteries contain: Sodium hydroxide Potassium hydroxide Lithium dioxide dry cell batteries ...

  19. PMAA-stabilized ferrofluid/chitosan/yeast composite for bioapplications