• Korean Journal of Food Science and Technology
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• v.29 no.3
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• pp.588-594
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• 1997

Yeast strains useful for the production of wine using mandarine orange, Citrus unshiu, as a main substrate were screened, and their primary ability to decompose citric acid that affects directly wine quality was investigated. Total eleven strains were selected for brewing orange wine. Five wild strains were from soil-based collections and identified: four of them were Saccharomyces cerevisiae and one of them was S. ellipsoideus. The rest of six strains were from among eighteen laboratory strains: three of them were S. cerevisiae, and the other three were S. coreanus, S. uvarum, and S. sake. Two strains of S. cerevisiae out of these selections were chosen and their decomposition of citric acid was investigated. Citric acid was not utilized as sole carbon source for cellular growth. However, when both citric acid and glucose were added together as carbon sources, decrease of citric acid concentration was observed after incubation. Shaking incubation was more effective for the reduction of citric acid than standing incubation. Utilization of citric acid did not contribute to the increase of ethanol concentration during fermentation. On the other hand, it appeared that citric acid caused partial inhibition of cellular growth of the yeasts.

• Korean Journal of Food Science and Technology
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• v.17 no.5
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• pp.350-354
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• 1985

For the purpose of studying the possibility to use the barley as a raw material in vinegar manufacturing process, several factors related to the fermentation of acetic acid were investigated. The optimum quantity of sweet liquor prepared by koji method in medium was 30-40%. When koji of A. oryzae, commercial enzyme products and malt were used for the saccharification of the barley, the production rates of acetic acid during log period were 0.056%/hr, 0.025%/hr, 0.03896/hr and lag period were 22 hours, 48.5 hours and 25 hours, respectively. These results indicate that the saccharifying method using koji of A. oryzae is superior to that by the commercial enzyme products or malt for the acetic acid fementation. The optimum initial acidity was 2% and the proper initial ethanol degree were 4-6% in metium. In a submerged culture process using a jar fermentor, lag period was 15 hours, and acetic acid fermetation period was about 45 hours. In the sensory test of barley vinegar and commercial vinegar of the market, barley vinegar was superior to the vinegar in market with respect to tastes.

• Microbiology and Biotechnology Letters
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• v.16 no.4
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• pp.297-302
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• 1988

The protoplasts of Saccharomyces cerevisiae D-71, a thermophilic strain and Zygosaccharomyces rouxii SR-S, an osmotolerant strain were fused, and a fusant (FS-RN 1) was selected, then was characterized for its genetic stability, DNA content, cell capacity, growth rate, tolerance to salts and chemicals, $\beta$-fructofuranosidase level and ethanol fermenting activity. After 6 months of preservation, 5.8% of the fusant clones were segregated to parental types. The DNA content and cell capacity of the fusant were greater than those of the parental strains. Lag period of growth for the fusant was longer than those for the parents. The fusant colonies showed pink-color reaction to triphenyltetrazolium chloride(TTC) test. The fusant appeared to have resistances to NaCl at moderate levels between both parental strains, and resistances to KCI, sodium propionate and cycloheximide similar to either one of the parents. $\beta$-Fructofuranosidase activity of the fusant was 24.2$\times$10$^{-3}$/IU/g(dry wt) for 3 days culture. Ethanol yields ofter 4 days of fermentation by the fusant at 3$0^{\circ}C$ were : 6.0%(v/v) from 40% of glucose and 8.8%(v/v) from 20% of sucrose.

• The Korean Journal of Pesticide Science
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• v.4 no.3
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• pp.52-59
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• 2000

A rapid assay to determine respiration inhibition of Saccharomyces cerevisiae by chemicals was developed. S. cerevisiae was harvested with two different liquid media, yeast extract-peptone-dextrose (YPD) medium capable of occurring both glucose fermentation and mitochondrial respiration, and non-fermentable carbon-yeast extract (NFY) medium capable of occurring respiration only Wells in 96-well plate were loaded with each cell suspension and various concentrations of 46 fungicides with various modes of action. n NFY medium, the non-fermentable carbon source, ethanol (NFY-E medium), glycerol (NFY-G medium) or lactate (NFY-L medium), was used. After incubation for $1{\sim}3$ days, minimum inhibitory concentrations (MICs) of the chemicals were recorded in the media. Of the 46 inhibitors employed in this study, four inhibitors of fungal respiration by blockage of electron flux in the mitochondrial respiratory chain, azoxystrobin, kresoxim-methyl, metominostrobin, and trifloxystrobin, exhibited strong antifungal activity in all of NFY media, but no activity in YPD medium. In contrast to this, five N-trihalomethylthio fungicides showed much stronger antifungal activities in YPD medium than three NFY media. Eleven fungicides inhibited growth of S. cerevisiae in all media and the other 26 fungicides showed no antifungal activity in all media. Thus, our rapid and efficient in vitro method can be considered as an alternative assay system for respiration inhibitor.

• Korean journal of food and cookery science
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• v.12 no.2
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• pp.153-161
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• 1996

A curd yogurt was prepared from egg white powder (EWP) and casein added with sugars (glucose, fructose, lactose). The effects of sugar addition on acid production and growth of Lactobacillus were studied. The effects of sugar addition on sensory property and volatile aroma compounds were also studied. Acid production by L. acidophilus in EWP 2％ (W/V), casein 3％ (w/v) and sugar 0.5,1 or 2％ W/V) was lower than that of L. acidophilus in milk (control). Acid production in sample added with glucose or fructose of 1％ or 2% (W/V) was higher than that of 0.5% (W/V), while acid production in lactose added sample was not affected with the concentration of lactose. Number of viable cells of L. acidophilus at 24 hr in milk, glucose added sample, fructose added sample and lactose added sample was 3.6${\times}$10/Sup 9/, 5.6${\times}$10$\^$8/, 6.0${\times}$10$\^$8/,and 3.2${\times}$10$\^$7/, respectively. Through 30hr fermentation, acid production and number of viable cells of L. acidophilus in milk were higher than those of sugar added samples. Sensory property of fructose added sample was slightly better than that of milk yogurt (reference), while that of lactose added sample was significantly inferior. Though the composition of volatile aroma compounds was slightly different according to sample, gas chromatographic analysis detected acetone, ethanol, diacetyl and acetoin in samples fermented by L. acidophilus.

• Korean Journal of Food Science and Technology
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• v.33 no.5
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• pp.603-610
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• 2001

The quality characteristics of soy yogurt prepared with different proteolytic enzymes and starter culture were evaluated. In order to facilitate the growth of lactic acid bacteria and subsequent production of lactic acid, soy protein isolate(SPI) was hydrolyzed using three kinds of proteases; one extracted from Aspergillus oryzae, bromelain and ${\alpha}-chymotrypsin$. The cultural systems employed thereafter for lactic fermentations were: 1) Bifidobacterium bifidum, 2) B. bifidum and Lactobacillus acidophilus, 3) B. bifidum and Lactobacillus bulgaricus. In soy yogurt, pH was more decreased by mixed culture method than single culture method with the accumulation of lactic acid. Viable cells of lactic acid bacteria in soy yogurts were measured $10^8$ CFU/g by the single culture method while $10^9$ CFU/g by the mixed culture method except ${\alpha}-chymotrypsin$ treatment. The amount of free amino acids in soy yogurts were substaintially increased by enzyme treatment. Viscosity was decreased by enzyme treatment, resulting in higher viscosity by ${\alpha}-chymotrypsin$ treatment. Water holding capacity was found to be higher in the single culture method in case of enzyme treatment. Among the various volatile flavor components isolated and identified after enzyme hydrolysis, acetaldehyde, ethanol, diacetyl, butyl alcohol contents tended to increase by lactic fermentation.

• Korean Journal of Food Science and Technology
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• v.53 no.3
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• pp.260-266
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• 2021

This study aimed to identify the hepatoprotective effects of a fermented Chrysanthemum indicum L. water extract. The extraction yield, antioxidant activities (ABTS and DPPH), and content of luteolin and luteolin-7-glucoside were significantly higher in the fermented C. indicum L. water extract (FCI) than in the C. indicum L. water extract. Treatment with FCI (200 ㎍/mL) significantly reduced the activities of gamma(γ)-glutamyl transferase, aspartate aminotransferase, alanine aminotransferase, and lactate dehydrogenase in HepG2 cells treated with 3% ethanol. Furthermore, FCI did not affect the viability of the HepG2 cells. These results suggest that FCI can be useful for the development of an effective hepatoprotective agent.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.6
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• pp.796-804
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• 2010

This study was conducted to compare and analyze the qualitative property of MLT (mulberry leaf tea) and FMLT (fermented mulberry leaf tea) based on the antioxidant, anticancer activities of various extracts. When the antioxidant activity of MLT and FMLT extracts was evaluated, the electron donating activity was found to increase proportionally as the concentration of each extract increased. In addition, the extract of FMLT showed a higher electron donating activity than that of MLT. Furthermore, the ethanol extracts showed the highest electron donating ability. When the SOD activity was evaluated, it was also found to increase proportionally with the concentration of each extract. Furthermore, the SOD activity of the ethanol extract group was the highest, whereas the SOD like activities of both MLT and FMLT were similar. When nitrite decomposition was evaluated for each pH, the highest value was observed at pH 1.2. Finally, the nitrite deleting ability was the highest for the ethanol extracts. When each extract of MLT and FMLT was analyzed in vitro for anticancer effects, they were found to decrease the number of cancer cells proportionally as the concentration of extract increased for both HeLa cells and MCF-7 cells. Furthermore, FMLT was found to exert a greater inhibition of cancer cells than MLT. Among the extract groups, the ethanol extract induced the greatest inhibition of the development of cancer cells, and these effects were greater against MCF-7 cells than HeLa cells.

• Journal of the East Asian Society of Dietary Life
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• v.23 no.4
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• pp.437-443
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• 2013

Rice wine (makgeolli) containing various amounts of mountain ginsengs (MG) are being prepared with nuruk and yeasts, and the physicochemical characteristics and contents of ginsenosides in MG-makgeolli were analyzed. Average particle size of MG powder is $29.1{\mu}m$. MG slice (20 g) or powder (0~20 g) and rice (3,000 g) were used for 12 days fermentation of makgeolli, makgeolli containing slice of MG (SW-makgeolli), makgeolli containing 2 g (PW1-makgeolli), 10 g (PW2- makgeolli), 20 g (PW3-makgeolli) of powder of MG, respectively. Soluble solids and pH levels show no differences between five kinds of makgeolli groups, whilst the presence of high amounts of MG (PW3-makgeolli) caused decreases in ethanol and acidity. Major free amino acids in MG-makgeolli are glutamic acid and arginine. Total contents of 14 ginsenosides are approximately 2.5 g/100 g of dried MG powder and major ginsenoside were ginsenosides Re, Rb1, Rb2, Rg1, Rc and Rf. During the propagation of makgeolli containing MG, the ginsenosides Rb1, Rb2, Rb3, and Rc decreased, whilst ginsenosides Rg3 and compound K increased highly. It indicates that ginsenosides in MG are metabolized to different forms of ginsenosides by brewing microorganisms.

• BMB Reports
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• v.48 no.1
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• pp.42-47
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• 2015

Streptococcus mutans is frequently associated with dental caries. Bacterial fermentation of food debris generates an acidic environment on the tooth surface, ultimately resulting in tooth deterioration. Therefore, various mouthwashes have been used to reduce and prevent Streptococcus mutans. The aim of this study was to evaluate the antimicrobial activities of 4 commercial mouthwashes and those of 10% and 20% ethanol solutions (formula A, B, C, D, E and F) against Streptococcus mutans using biofilm and planktonic methods. The range of reduction in the viable cell count of Streptococcus mutans as estimated by the biofilm and planktonic methods was 0.05-5.51 log ($P{\leq}0.01$) and 1.23-7.51 log ($P{\leq}0.001$) compared with the negative control, respectively, indicating that the planktonic method had a stronger antibacterial effect against S. mutans. Among the tested formulations, formula A (Garglin $regular^{(R)}$ mouthwash) was the most effective against Streptococcus mutans ($P{\leq}0.001$).