• Korean Journal of Microbiology
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• v.52 no.2
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• pp.220-225
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• 2016

To improve antioxidant glutathione (GSH) content and saccharification ability in sake yeasts of Saccharomyces cerevisiae, the ${\gamma}$-glutamylcysteine synthetase gene (GSH1) from S. cerevisiae, glucoamylase gene (GAM1) and ${\alpha}$-amylase gene (AMY) from Debaryomyces occidentalis were co-expressed in sake yeasts for manufacturing a refreshing alcoholic beverage abundant in GSH from rice starch. The extracellular GSH content of the recombinant sake yeasts increased 1.5-fold relative to the parental wide-type strain. The saccharification ability by glucoamylase of the new yeast strain expressing both GAM1 and AMY genes was 2-fold higher than that of the yeast strain expressing only GAM1 gene when grown in the culture medium containing 2% (w/v) rice starch. It generated 11% (v/v) ethanol from 20% (w/v) rice starch and consumed up to 90% of the starch content after 7 days of fermentation.

• The Korean Journal of Food And Nutrition
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• v.12 no.4
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• pp.339-343
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• 1999

A strain of gas-producing and volume-expanding yeast was isolated from Gochujang made in Sunchang by the traditional ways and was identified to be a Saccharomyces sp. This yeast was detected only in malt among the several ingrediants of Gochujang which means that the volume-expanding yeast comes into Gochujang at the time of making products through malt one of the major ingredients. However boiling of the malt-saccharified rice could not prevent the occurrence of the volume-expanding yeast in Gochuj-ang. This yeast was contained in the range of 5.67∼7.75 log10CFU/g in products made and aged between 1 monty and 3 year in Sunchang area.

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.3
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• pp.354-357
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• 2005

The in vitro degradability of yeast and the effect of yeast on the in vitro degradability of forage may differ in terms of the specific yeast strains or their incubation conditions. Thus in experiment 1, two strains of sake yeast (strainK7 and strainK9) and one strain of bakers' yeast (KY5649) were incubated in an aerobic condition. In experiment 2, aerobically or anaero bically incubated K7 was used for investigating the in vitro degradability of yeast, the effect of yeast on the in vitro degradability of forage, and the degradability of yeast by pepsin and pronase treatment. The in vitrodegradability of bakers' yeast was significantly (p<0.05) higher than those of sake yeasts. The in vitro degradability of anaerobically incubated yeast was significantly (p<0.01) higher than that of aerobically incubated yeast. The degradability of bakers' yeast by pepsin treatment was significantly (p<0.01) higher than that of the sake yeasts. The degradability of bakers' yeast by pronase treatment was slightly higher than that of the two sake yeasts, while the degradability of anaerobically incubated yeast by both enzymes, respectively, was significantly (p<0.01) higher than that of aerobically incubated yeast. The degradability of forages was increased significantly (p<0.05) by the addition of yeasts. The degradability of roughage by sake yeast tended to be higher than that by the bakers' yeast. The degradability of roughage was significantly (p<0.05) higher by anaerobically incubated yeast than by aerobically incubated yeast. Given the above results, it seems that in vitro degradability of yeast and the magnitude of the increment of roughage degradation differ among the yeast strains and their incubation conditions.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.6
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• pp.1022-1027
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• 2004

The monacolin K content was determined to investigate the stability of monacolin K from red yeast rice after heating (20∼8$0^{\circ}C$), adjusting the pH (2∼8) by adding 3 N HCl or 3 N NaOH, adding the organic acid (6.0% acetic acid, 0.6% citric acid, 1.5% lactic acid) to pH 4.0 and adding the water (0∼80%). And the monacolin K was isolated from red yeast rice by conducting open column chromatography using neutral aluminum oxide. As a result, the stability of monacolin K decreased with increasing the temperature. The stability for pH was in the order of the unadjusted pH (pH 5.9)>8>4 and pH 2>10. The stability for organic acid was high in the order of lactic acid>citric acid>acetic acid, and the stability of monacolin K under acid was different according to the acid type. The degradation rate of monacolin K increased with increasing the water content. Moreover monacolin K was able to isolate from red and pink pigments as well as the other noncoloric compounds in red yeast rice. The yield of monacolin K was found to be 70%.

• Journal of Life Science
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• v.33 no.2
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• pp.183-190
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• 2023

Red yeast rice, also known as Hong Qu and red Koji, has been used for a long time in Asian functional food and traditional medicine. It consists of multiple bioactive substances, which can potentially be used as nutraceuticals. Alcoholic liver disease (ALD) can range from simple steatosis or inflammation to fibrosis and cirrhosis, possibly through leaky gut and systemic endotoxemia. This study examined the liver and gut effects of red yeast rice (RYR) (Monascus purpureus) ethanol extract against binge ethanol-induced liver injury in mice. RYR extract was orally administered to C57BL/6N mice at a concentration of 200 mg/kg body weight per day for 10 days. Then, mice were administered binge alcohol (5 g/kg/dose) three times at 12 hr intervals. Binge alcohol exposure significantly elevated the endotoxin, aspartate aminotransferase (AST), and alanine transaminase (ALT) activity of plasma, as well as hepatic triglyceride levels; however, RYR treatments reduced these levels. In addition, RYR pretreatment significantly reduced the alcohol-induced oxidative maker protein and apoptosis maker in binge alcohol-induced gut and liver injuries. These results suggest that RYR may prevent alcohol-induced acute leaky gut and liver damage.

• The Korean Journal of Mycology
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• v.46 no.3
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• pp.307-314
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• 2018

The goal of this study was to investigate the microbiological characteristics of the ethanol-producing wild yeast, Aureobasidium pullulans P-1, isolated from flowers growing near the Yedang reservoir, Chungnam province, Korea, and in addition, to optimize its fermentation ability for the production of Makgeolli. A. pullulans P-1 was oval-shaped, and formed ascospores and pseudomycelium. The P-1 strain was a halophilic and sugar tolerant yeast which grew in 15% NaCl and 50% glucose-containing yeast extract-peptone-dextrose media. The P-1 strain was also resistant to 20% ethanol. Changes of the physicochemical properties during Makgeolli fermentation by A. pullulans P-1 were investigated. A maximum of 8.45% ethanol was obtained when a mixture of cooked rice, 150% water, and 35% ipguk per cooked rice was fermented by 5% A. pullulans P-1 culture broth at $25^{\circ}C$ for 10 days. Antihypertensive angiotensin I-converting enzyme inhibitory activity in the Makgeolli ferment produced by A. pullulans P-1 reached a high of 71.1% after 10 days.

• Korean journal of food and cookery science
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• v.18 no.5
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• pp.516-521
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• 2002

This study was investigated to prove the relation between the ingredient of Samul Chol-Pyon and its microorganism pollution level during the storage. As a result, the pollution degree in total aerobic bacteria, yeast, mold, and colitis germs of rice power turned out to have a lower one than the oriental medicine materials do. In case of preserved write Chol-Pyon, the total aerobic bacteria pollution level was 8.8 $\times$ 10$^3$CFU/g the highest degree among other ones in their among other ones in their early pollution levels and in the oriental medicine materials, the pollution level was degreased as its annex increased. Moreover, yeast propagated fast in its first day of storage, but mold grew somewhat slowly than yeast and total aerobic bacteria did. In every case, the range of colitis germs growth was between 10$^2$-10$^3$CFU/g and it was similar to the each one of total aerobic bacteria, yeast, and molds. On its third day of storage, the pollution level of mold showed 10$^4$-10$\^$5/CFU/g.

• Journal of Nutrition and Health
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• v.41 no.1
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• pp.31-40
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• 2008

This study was aimed at evaluating the effect of red-yeast-rice supplementation on cholesterol-lowering and glucose control in subjects with impaired fasting glucose (IFT) or impaired glucose tolerance (IGT). We conducted a doubleblind, placebo-controlled study with 3 groups; placebo, low dose group (red yeast rice 210.0mg/capsule, 2.52g/day) and high dose group (red yeast rice 420.0mg/capsule, 5.04g/day), which were randomly assigned to subjects with impaired fasting glucose or impaired glucose tolerance. We measured fasting serum concentrations of total-, LDL-, HDL-cholesterol, triglyceride, glucose, insulin, free fatty acid (FFA) and 2 h oral glucose tolerence test (OGTT) before and after the supplementation. Both low dose and high dose groups had significant decrease in LDL cholesterol and atherogenic index (AI) compared with placebo group (p<0.05). Additionally, total and HDL cholesterol improved significantly in high dose group compared with placebo group (p<0.05). Fasting serum glucose decreased in test groups and increased in placebo group after intervention. However, it was not significant differences. In subjects which fasting blood glucose is more than 110mg/dL, fasting glucose had a tendency to decrease in high dose group (p<0.1) and Hemoglobin A1c (HbA1c) had significant decrease in low dose group (p<0.05), while insulin and HOMA-IR had a tendency to increase in placebo group after intervention. Mean changes of glucose related parameters (fasting glucose, insulin, HOMA-IR) compared with placebo group did not show significant differences. In conclusion, subjects with impaired fasting glucose or impaired glucose tolerance were significantly improved in serum lipid profile by red yeast rice supplementation without serious side effects. These are more effective in the case of a high dose. The effects of red yeast rice supplementation on glucose control were insignificant.

• Proceedings of the Korean Society of Potoscience Conference
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• 2006.06a
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• pp.19-19
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• 2006

• Microbiology and Biotechnology Letters
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• v.43 no.3
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• pp.227-235
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• 2015

The objective of this study was to improve the quality of Korean rice wine with wild type yeast strains isolated from various traditional Korean fermented foods. Herein the fermentation and sensory characterization of wild yeast, for the purposes of brewing Korean rice wine, was investigated. 12 yeast strains were examined for their ethanol and glucose tolerance. In addition, the pH, soluble solids, acidity, amino acidity, ethanol content, organic acids, and volatile compounds were also studied for the alcoholic beverages made with the wild yeasts. Almost all Saccharomyces genera yeasts were showed to have a tolerance at 10% ethanol, but non-Saccharomyces genera yeasts displayed a low tolerance. The alcoholic beverages fermented by non-Saccharomyces yeasts demonstrated higher levels of soluble solids, titratable acidity, amino acids, and lower ethanol content, when compared with the alcoholic beverages fermented by Saccharomyces genera yeasts. The organic acid content, such as malic acid, acetic acid, and succinic acid, was seen to also be higher. The electronic nose was analyzed, and discriminant function analysis (DFA) was used for discriminating wild yeast strains. The DFA plots indicated a significant separation of Saccharomyces genera and non-Saccharomyces yeast strains. For volatile compounds, ethyl acetate from non-Saccharomyces yeasts, and ethanol from Saccharomyces genera yeast, a high area ratio was observed.