• Journal of Ginseng Research
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• v.10 no.1
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• pp.1-10
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• 1986

To evaluate the possible utilization of ginseng by-products, chemical components of ginseng residue, reducing ability of DPPH, effect of residue extract on the yeast growth, amino acid contents of yeast cell, increase of residue extract yield by enzyme treatment were studied. Alcohol and water extract residue contained 43-46% total reducing sugar and 14-15% crude protein, while alcohol extract residue had 0.18% n-BuOH extract. Water extract of alcohol extract residue had about 45% reducing ability of DPPH in comparison with that of alcohol extract from ginseng roots. Essential nutrients for the yeast growth were found in extract when Saccharomyces cerevisiae was cultured in Czapeck medium, a compound medium, with the residue. The addition of residue extract to malt medium, a natural medium, enhanced 30-40% yeast growth. And content of each amino acid in yeast cell cultured on malt medium with ginseng residue extract was much more than that of the cell cultured without ginseng extract, but amino acid composition of yeast cell did not differ from one another. The treatment of alcohol extract residue with cellulase increased 250% yield of residue extract.

• Food Science and Preservation
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• v.5 no.2
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• pp.186-190
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• 1998

In order to investigate the possible application of immobilized yeast cells in sparkling wine production instead of riddling puns by the traditional method, fermentation characteristics were tested during the sparkling wine fermentation in the bottle using immobilized yeast cells with alginate. The rates of sugar consumption and alcohol production were faster with free cells than those with immobilized cells during the fermentation. The higher concentration of yeast cells and the lower concentration of alginate in the cell immobilization resulted in the faster sugar consumption and alcohol production. It also resulted in the increase of yeast cell concentration released from immobilized beads during the fermentation. However, no differences were shown in the contents of alcohol, residual sugar and CO2 pressure after fermentation. In case concentration of yeast cells released from immobilized beads during bottle fermentation, the higher concentration of alginate had and the lower had.

• 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.

• Journal of Ginseng Research
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• v.10 no.2
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• pp.209-217
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• 1986

Yeast alcohol dehydrogenates and ginseng saponin interaction has been investigated to understand the non-specific enzyme stimulating effect of the saponin of Panax ginseng C.A. Meyer. It was confirmed that several amphiphiles such as sodium dodecyl sulfate(SDS), Triton X-100, sodium taurodeoxycholate (Na-TDC) as well as ginseng saponin mixture and purified ginseng glycosides lowered Km values of yeast alcohol dehydrogenase (ADH) for ethanol and NAD in the presence of the above amphiphiles suggesting that the surface activity of the amphiphiles might play a significant role in the ADH catalyzed reactions. Conformational change of yeast alcohol dehydrogenase in the presence of the above amphiphiles at their optimal concentration for the maximum activity was studied. Circular dichroism (C.D) spectrum of yeast ADH showed that the conformational change of the enzyme occurred in the presence of above amphiphiles. Fluorescence data also showed that the hydrophobic area increased in the presence of above amphiphiles. Examination of the interaction between ADH and ginseng saponin using radioactive saponin showed that there might be a very weak interaction between them. From the above results, it was concluded that the non-specific enzyme stimulating effect of the saponin might be due to the change of polarity of the enzyme solution in the presence of the saponin.

• Food Science and Biotechnology
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• v.17 no.6
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• pp.1207-1213
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• 2008

The possible protective effects of highly zinc-containing yeast Saccharomyces cerevisiae, FF-10 strain, isolated from tropical fruit rambutan on acute alcoholic liver injury in rats were evaluated. Zinc concentration in this strain was 30.6mg%. The activities of serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), and $\gamma$-glutamyl transpeptidase ($\gamma$-GTP) were highly increased when alcohol was treated, relative to the normal rats. Also, a highly significant increase in the blood alcohol and acetaldehyde levels by alcohol treatment was observed. Administration of FF-10 strain markedly prevented alcohol-induced elevation of the activities of serum ALT, AST, and $\gamma$-GTP, and the levels of blood alcohol and acetaldehyde, and these reduced levels reached to that of normal rats. As compared with alcohol treated control rats, the FF-10 strain supplementation showed highly decreased the triglyceride concentration in serum. Alcohol treatment induced the marked accumulation of small lipid droplets, hepatocytes necrosis, and inflammation, but FF-10 strain administration attenuated to alcohol-induced accumulation of small lipid droplets and hepatocyte necrosis in the liver. Therefore, the current finding suggests that zinc-enriched yeast FF-10 strain isolated from tropical fruit rambutan may have protective effect against alcohol-induced hepatotoxicity.

• Mycobiology
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• v.39 no.1
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• pp.33-39
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• 2011

Wild yeasts on the surface of various fruits including grapes were surveyed to obtain yeast strains suitable for fermenting a novel wine with higher alcohol content and supplemented with rice starch. We considered selected characteristics, such as tolerance to alcohol and osmotic pressure, capability of utilizing maltose, and starch hydrolysis. Among 637 putative yeast isolates, 115 strains exhibiting better growth in yeast-peptone-dextrose broth containing 30% dextrose, 7% alcohol, or 2% maltose were selected, as well as five ${\alpha}$-amylase producers. Nucleotide sequence analysis of the 26S rDNA gene classified the strains into 13 species belonging to five genera; Pichia anomala was the most prevalent (41.7%), followed by Wickerhamomyces anomalus (19.2%), P. guilliermondii (15%), Candida spp. (5.8%), Kodamaea ohmeri (2.5%), and Metschnikowia spp. (2.5%). All of the ${\alpha}$-amylase producers were Aureobasidium pullulans. Only one isolate (NK28) was identified as Saccharomyces cerevisiae. NK28 had all of the desired properties for the purpose of this study, except ${\alpha}$-amylase production, and fermented alcohol better than commercial wine yeasts.

• Food Science and Preservation
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• v.24 no.7
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• pp.1043-1051
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• 2017

Wild yeasts were isolated from domestic non-sterilized Makgeolli and their fermentation characteristics were analyzed to select the best fermentation seed culture. A total of 65 yeast strains isolated yeasts from non-sterilized Makgeolli and Nuruk. In order to select fermentable strains, hydrogen sulfide, $CO_2$ production ability, alcohol tolerance and aroma component production ability were analyzed. To screen the aromatic strains of isolates, media containing cerulenin, 5,5,5-trifluor-DL-leucine (TFL) and API ZYM kit were used. There were 36 strains resistance to cerulenin and all strains produced esterase and demonstrated tolerance against TFL. Hydrogen sulfide, which could degrade the quality of the fermented beverage, was not produced in 34 yeast. The correlation between alcohol tolerance of yeast and carbon dioxide production was analyzed by principal component analysis. YM22, YM31, YM32 and YM37 produced a total of 0.14-0.18 g/72 h of $CO_2$ indicating high fermentability. Alcohol tolerance was measured by alcohol concentration. YM32, YM37 yeast had 20% alcohol tolerance. As a result, alcohol and flavor characteristics of wild yeast isolated from non-sterilized Makgeolli were analyzed and it was confirmed that yeast was suitable for the production of alcohol.

• KSBB Journal
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• v.6 no.3
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• pp.255-261
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• 1991

The effect of concentration of yeast extract and NH4Cl in the mediun of alcohol fermentation of S. cerevisiae ATCC 24858 on the fermentation characteristics, specific growth rate, sugar conversion, alcohol productivity was experimentally investigated. Regardless of initial sugar concentrations, the values of the above three characteristics increased with augument of concentration of yeast extract. However, the increasing tendency ceased above a certain concentration. The concentration of NH4Cl had little effect on the change of the three characteristics. The functional relationships between the concentration of yeast extract and the characteristics were different according to the initial sugar concentrations, but those between the ratio of yeast extract concentration to initial sugar concentration and the characteristics could be expressed as same forms respectively regardless of initial sugar concentrations. Also the values of the three characteristics approached to the maximum values around 0.085 of the ratio, but did not increase any more above 0.1 of the ratio. We have come to conclusion that the optimum ratio of the yeast extract concentration to the initial sugar concentration was about 0.085 and the ratio should not be decided as greater than 0.1 in the medium of alcohol fermentation of S. cerevisiae ATCC 24858.

• Food Science and Preservation
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• v.17 no.2
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• pp.174-181
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• 2010

The yeast strains used for fermentation are known to influence the qualities of wine. We investigated the effects of fermentation using different yeast strains on the properties of wine produced from 'Hayward' kiwifruit (Actinidia deliciosa). The physicochemical characteristics of wine produced using various yeast strains for fermentation were also analyzed. Saccharomyces cerevisiae Gervin No.5 strain (GVN), S. bayanus Lavin strain EC1118 (EC1118), and S. cerevisiae Red star Davis No. 796 (No.796) are commercial dry yeast strains selected for optimization of fermentation. Although the soluble solid contents of samples fermented by all three yeast strains decreased by a similar extent, the levels of alcohol production differed, particularly during the first week of fermentation. Use of the GVN strain resulted in the highest alcohol concentration (13.8%, v/v), whereas fermentation with No.796 and EC1118 strains yielded alcohol contents of 13.0% and 12.5% (both v/v), respectively. Upon sensory evaluation, GVN-fermented wine had a strong taste and bitterness, with high acid and alcohol contents. Wine fermented using No.796 had a chemical profile similar to that of GVN-fermented product, but the taste remained sweet, consistent with the lower alcohol content. EC1118-fermented wine was soft and sweet in taste, high in flavor, and had a low alcohol content. Total phenolic levels and antioxidant activities in wine fermented by EC1118 were significantly higher than in wines prepared using No.796 or GVN. When previously described characteristics were additionally considered, EC1118 was selected as an optimum strain for further study. In conclusion, fermentation of kiwifruit using different yeast strains yielded wines with distinct characteristics. The yeast strain EC1118 had the most desirable properties, and is considered suitable for kiwifruit fermentation. Valuable attributes of wine fermented by this yeast include overall sensory acceptance, an appropriate level of total phenolics, and good antioxidant activity.

• Food Science and Preservation
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• v.18 no.5
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• pp.779-785
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• 2011

This study was conducted to investigate and compare the characteristics of alcohol fermentation in oriental melon by different yeast. As a result, no significant difference in pH, total acidity and sugar content was found in alcohol fermentation of oriental melon by different yeast. The pH was shown to be constantly maintained but the total acidity was shown to increase during fermentation process. The sugar content was rapidly decrease starting from 3 day of fermentation, and it was reduced to be approximately 7 oBrix after fermentation. For organic acid content, lactic and citric acid contents were shown to be the highest in all periods of fermentation, which revealed that lactic and citric acid were major organic acids. Free sugar content were shown to gradually decrease during the fermentation and to be rarely detected at 9 days of fermentation. Alcohol content was shown to be 14.20% at (C) S. cerevisiae RC-212, which was the highest content. It was shown to be more than 12% at other periods, which showed that no significant difference in alcohol content was found according to different yeast. For alcohol components, acetaldehyde content was shown to be the highest at (E) S. cerevisiae K1-V1116, and methanol content was shown to be relatively higher at (C) S. cerevisiae RC-212 and (D) S. bayanus EC-1118. N-propanol, 2-methyl-1-propanol and isoamyl alcohol, which belong to fusel oil, were shown to be produced at 3 day of fermentation and gradually increase. These results, no significant difference in physicochemical properties of alcohol fermentation in oriental melon by different yeast.