• Microbiology and Biotechnology Letters
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• v.25 no.5
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• pp.512-519
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• 1997

RNA accumulating strain of Torulopsis versatilis MT-1 was cultured in molasses medium for higher contents of RNA in cell. Yeast cells were harvested at logarithmic phase on synchronous culture. Yield of cells on dry base to input sugar was 59.5%. Crude protein content was 55.1% in cell. RNA content was 13.9%. Some problems found in the process for the preparation of yeast extracts were improved by the addition of culture broth of Streptomyces faecalis MSF which secrete RNase (5' nuclease and 5' adenylic acid deaminase). When the culture broth of S. faecalis MSF was added in autolysis process 46% of RNA in cell was converted to I and G(5' inosinic acid and 5' guanylic acid) in extract. By addition of 3-7% culture broth of S.faecalis MSF in autolysis or enzymolysis process at the start or early stage, RNA in extract was converted easily to I and G and protein in cells was easily extracted and hydrolyzed to amino acid. Taste of those yeast extracts was delicious. The yeasty smell in yeast extracts was removed. And cell debris was easily removed from extract.

• Journal of Ginseng Research
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• v.3 no.2
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• pp.95-104
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• 1979

The effects of ginseng extracts on carbon dioxide generation, alcohol fermentation, and yeast cell production by Saccharomyces cerevisiae were investigated. The results are as follows. 1) In the process of fermentation, CO2 generation by yeast is faster in ginseng extracts media of 0.3%, 0. l% than in control. As the concentration of the extracts increases by 0.7% and 1.5%, CO2 generation is decreased. Among all these concentrations, CO2 generation is fastest in 0.3% of the extracts. 2) In the process of fermentation, the production of alcohol is larger in the order of 0.3%, 0.7% and 0.1% than in the control and least in 1.5%. 3) The number of yeast cell rapidly increased from 12 hours to 18 hours after cultivation and conspicuously increased in the order of 0.3%, 0.7%, 0.1%, control and 1.5%. 4) Dried yeast cell weight increased more in all the above concentration than control and among these it increased visibly in 0.3% of the extracts.

• Journal of Animal Environmental Science
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• v.6 no.3
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• pp.201-209
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• 2000

Optimal conditions to utilize egg type male chicks from hatchery for cultivating yeast(Saccharomyces cerevisiae) and the effects of the yeast culture on growth of broiler chicks were investigated. The protein concentration of the spent cockerel extracts was the highest when extracted for 72 hours. Optimal water volume added to the spent cockerel chicks for the extraction was 1.5 times to the cockerel chicks weight (v/w ratio). Lipid in the extracts from the spent cockerel chicks did not affect on the yeast growth. The number of yeast cultured in the SCELP2 medium containing spent cockerel extracts and 4 % sugarcane molasses was higher by 26 % than that in the YEPD medium containing 1 % yeast extract, 2 % bacto pepton and 2 % glucose. Also the number of yeast cultured in the SBYW2 medium containing SCEP2 medium containing SCELP2 and 4 % brewer's yeast waste was increased by 8 %, compared to that in the SCELP2 medium. Body weight gain of chicks fed 4 % yeast culture supplementations cultivated in the SBYW2 medium was increased at 5 weeks by 9 %, relative to no supplementation(P<0.05). The results from this study suggest that the spent cockerel chicks can be utilized as nitrogen sources to produce yeast culture for animal feed.

• Journal of Life Science
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• v.18 no.4
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• pp.550-555
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• 2008

This study focused on alcohol fermentation properties of red ginseng extracts using Saccharomyces cerevisiae JF-Y3. Central composite design was employed to investigate the influence of red ginseng extract content ($10{\sim}50%$, v/v) and yeast extract ($0.5{\sim}2.5%$, w/v) on the properties of alcohol fermentation added with red ginseng extracts. Yeast cell growth was affected both by red ginseng extract content and yeast extract content, and red ginseng extract content had a greater effect on yeast cell number than yeast extract content. Yeast cell number increased along with decrease of the red ginseng extract content and with increase of yeast extract content. Alcohol content was maximal at 30% red ginseng extracts and 0.50% yeast extract and the predicted maximum value of alcohol content was 12.45%. Brix degree and total sugar content were significant within 1% level (p<0.01), and brix degree was affected both by red ginseng extract and yeast extract content. Total sugar content was significantly affected by red ginseng content.

• Korean Journal of Food Science and Technology
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• v.34 no.5
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• pp.867-872
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• 2002

This study was performed to investigate the optimum process conditions for manufacturing yeast extract from waste brewer's yeast using various enzymes. Contents of IMP, GMP, free amino acids, and crude protein of yeast extracts were measured by enzymes treatment. Crude protein contents of yeast extracts subjected to cell wall digestion enzyme treatment were 21.1, 33.6, and 28.0% for the control grouup, glucanase (0.5%, 12 h), and tunicase (1%, 18 h), respectively. Crude protein contents of yeast extracts subjected to protease treatment were 22.0, 30.8, and 29.8% for control group, bromelin (1%, 3 h), and protamex (1%, 3 h), respectively. Crude protein content of yeast extract subjected to glucanase and protamex mixed treatment was 34.4%. The total contents of IMP and GMP of yeast extracts subjected to G+P+A (glucanase+phosphodiesterase+adenyldeminase) and G+Pro+P+A (glucanase+protamex+phosphodiesterase+adenyldeaminase) treatments were 1,066 and 1,047 mg/100 g, respectively. The content of free amino acids of yeast extract was the highest (2,302 mg/100 g) in G+Pro+P+A treatment. Optimum concentration and process condition of enzyme treatment to obtain yeast extract with high IMP, GMP, and free amino acid content were in the order of glucanase (0.5%, 12 h), protamex (1%, 3h), phosphodiesterase (0.1%, 3 h) and adenyldeaminase (1%, 1.5 h) treatments.

• Journal of the Korean Society of Food Science and Nutrition
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• v.46 no.3
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• pp.327-334
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• 2017

Water and 75% ethanol extracts were prepared from defatted green tea seeds and evaluated for their anti-yeast activities. The antimicrobial activities of defatted green tea seed extracts (DGTSEs) were tested against food-spoilage bacteria, yeasts, and molds. DGTSEs exhibited antimicrobial activities with minimum inhibitory concentrations of $39{\sim}1,250{\mu}g/mL$ against three bacteria, two molds, and all tested yeast strains. Ethanol extract showed higher antimicrobial activity than water extract. The stability of anti-yeast activities of DGTSEs was examined under different conditions of temperature, pH, and NaCl concentrations. The anti-yeast activities of DGTSEs were stable at pH 3~9, 0~20% NaCl, and $100^{\circ}C$ for 30 min. However, anti-yeast activities of DGTSEs decreased upon heating at $70^{\circ}C$ for 24 h or $121^{\circ}C$ for 15 min. DGTSEs were applied to food models to determine their inhibitory effects on yeast film formation. Water and 75% ethanol extracts were effective in preventing yeast film formation at concentrations more than 156 and $39{\mu}g/mL$ in soy sauce, 156 and $78{\mu}g/mL$ in pickle sauce, and 78 and $39{\mu}g/mL$ in kimchi, respectively.

• Toxicological Research
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• v.35 no.1
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• pp.25-35
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• 2019

The extracts of Plathymenia reticulata and Connarus favosus are widely used in the folk medicine. The potential protective effects of these extracts have been evaluated against cadmium in the yeast Saccharomyces cerevisiae, and against mercurial contamination in zebrafish Danio rerio. In yeast, both extracts efficiently protected the ${\Delta}ycf1$ mutant strain exposed to cadmium chloride restoring the growth, the expression of stress-response genes and decreasing the level of oxidative stress. In zebrafish, the supplementation of methylmercury-contaminated diet with both plant extracts similarly protected fish through the suppression of the methylmercury-induced lipid peroxidation, decrease of acetylcholinesterase activity, and restoring the expression levels of stress-response genes. This study particularly demonstrates the protective potential of both aqueous extracts against methylmercury, and could represent an interesting alternative for the Amazonian fish-eating communities to cope with the impact of chronic exposure to contaminated diets.

• Journal of Animal Environmental Science
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• v.7 no.1
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• pp.21-28
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• 2001

Optimal conditions for utilizing the slaughtered porcine blood and liver for yeast culture and the effects of the yeast cultures on the growth of broiler chicks were investigated. The quantity of yeast cultured for 24hours in the BSG medium containing blood extracts containing 5% glucose and in the LSG medium containing liver extracts containing 5% glucose were higher by 4% and 10%, respectively, than that in the YEPD medium containing 1% yeast extracts, 2% bacto pepton and 2% glucose. Optimal concentrations of ammonium sulfate supplementation to the BSG medium to increase the quantity of yeast cultured for 24 and 48 hours were 100 mM(1.3%) and 50 mM(0.65%), respectively. The optimal pH for yeast culture in BSG medium ranged from 6 to 7. One percent supplementation of either ammonium sulfate or taurine to LSG medium increased the quantity of yeast by 18% and 9%, respectively, compared to no supplementation. The body weight of chicks fed with 2% and 4% yeast culture supplementations cultivated increased at the 4th week by 10%, with relative to no supplementation. The results from this study suggest that the slaughtered porcine blood and liver can be utilized for yeast culture which is used in animal diets.

• Journal of Microbiology
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• v.45 no.2
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• pp.128-132
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• 2007

The red yeast Xanthophyllomyces dendrorhous (previously named Phaffia rhodozyma) produces astaxanthin pigment among many carotenoids. The mutant X. dendrorhous G276 was isolated by chemical mutagenesis. The mutant produced about 2.0 mg of carotenoid per g of yeast cell dry weight and 8.0 mg/L of carotenoid after 5 days batch culture with YM media; in comparison, the parent strain produced 0.66 mg/g of yeast cell dry weight and a carotenoid concentration of 4.5 mg/L. We characterized the utilization of carbon sources by the mutant strain and screened various edible plant extracts to enhance the carotenoid production. The addition of Perilla frutescens (final concentration, 5%) or Allium fistulosum extracts (final concentration, 1%) enhanced the pigment production to about 32 mg/L. In a batch fermentor, addition of Perilla frutescens extract reduced the cultivation time by two days compared to control (no extract), which usually required five-day incubation to fully produce astaxanthin. The results suggest that plant extracts such as Perilla frutescens can effectively enhance astaxanthin production.

• Microbiology and Biotechnology Letters
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• v.7 no.4
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• pp.191-195
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• 1979

This study was conducted to investigate the effect of saccharified extract of ginseng meal on alcohol fermentation and reproduction of yeast. Different concentrations of saccharified extract of ginseng meal in liquid medium were tested, and the experimental results obtained were summarized as follows : 1. In the process of alcohol fermentation of yeast, $CO_2$ output was much accelerated by the higher concentration of saccharied extracts from 1％ to 6％, but $CO_2$ output was disurbed at the concentrations of 10％ and 15％. .2. In the process of alcohol fermentation of yeast, the production of alcohol was increased by the higher concentration of saccharified extracts from 1％ to 6％, but decreased at the concentrations of 10％ and 15％. 3. Number of reproduced yeast cell after aerobic culture of Sacc. cervisiae was increased by the higher concentration of saccharified extracts from 1％ to 10％, but decreased at the concentration of 15％. The number of yeast cell at the concentratin of 10％ extract was 1.6 times more than that of control.