• Microbiology and Biotechnology Letters
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• v.6 no.1
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• pp.27-31
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• 1978

The malo-alcoholic fermentation characteristics of Schiozaccharomyces japonicus var. japonicus which was freshly isolated from strawberry were studied. A good assimilation of malic acid by the strain was observed under the following conditions：pH 4.2∼4.8, alcohol content less than 12％, sulfur dioxide concentration less, than 150 ppm, and less than 0.01％ of Mn$\^$2＋/ as MnSO$_4$. The strain could remove 0.3％ of malic acid completely in 6 days under stationary culture at 30$^{\circ}C$. Shaking the culture could promote growth of the strain but did not affect on the malo-alcoholic fermentation.

• Korean Journal of Microbiology
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• v.28 no.4
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• pp.345-350
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• 1990

In order to ferment D-xylose directly to ethanol, Yeasts capable of utilizing D-xylose as a sole carbon source and energy source were isolated from soil, sawdust and rotten woods. Among them, the yeast strain, which showed the best ability to produce ethanol, was identified as Candida sp. L-16 isolated from rotten woods. The optimal conditions for production of ethanol were 60rpm of agitation speed, 28j.deg.C of temperature, 4.5 of initial pH and 5% of D-xylose concentration. Ethanol production was reached to maximum state for 4 days culture. Under these optimal conditions, the maximum ethanol concentration and theoretical ethanol yield were 2.4%(v/v) and 74.4% of theoretical value, respectively.

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 2003.10a
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• pp.201.2-202
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• 2003

생체조직에 있어서 환원형 Glutathione(${\gamma}$-L-glutamyl-cysteinyl-glycine, GSH)은 항산화 작용, 간기능 회복 및 해독작용등의 생체 내에서 중요한 생리활성기능을 가지고 있다. 본 연구에서는 glutathione을 다량으로 함유하는 효모균주를 전통 발효주로부터 분리하여 최적 생산을 검토하였다. 분리된 균주는 형태학적, 생리학적 및 생화학적 특성을 검토한 결과 Saccharomyces cerevisiae로 동정되어 FF-8로 명명하였다. Glutathione 생산을 위한 Saccharomyces cerevisiae FF-8의 최적 생산조건은 YM(glucose 1.0%, acid peptone 0.5%, yeast extract 0.3%, malt extract 0.3%) 배지를 기본으로 하여 72시간 동안 진탕배양하면서 검토하였다. Glutathione 생산을 위한 최적 온도, 교반속도 및 pH는 각각 3$0^{\circ}C$, 100 rpm, 그리고 pH 6.0으로 나타났다. Glutathione 최대 생산배지조건은 탄소원으로 3%의 glucose, 질소원으로 3%의 yeast extract, 무기질원으로 0.06%의 KH$_2$PO$_4$및 전구체로 0.06%의 L-Cysteine으로 하였을 때 최대 생산량을 나타내었고, 최적 배지상에서 204$\mu\textrm{g}$/$m\ell$을 생산하였다.

• KSBB Journal
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• v.14 no.5
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• pp.543-549
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• 1999

For development of an integrated calorimetric bio-reactor to measure the metabolic heat dissipated during cell growth, a 5 liter jar fermenter was modified to measure the pulse length of automatic temperature control signals to set heater on and off, and the to send them to computer to calculate the cumulative heat supplied. Cumulative heats for the calorimetric reactor in the absence of cell growth, were measured with varying conditions. The heat loss by the aeration was 30.9 kJ/vvm and the loss to ambient air was 10.5 kJ/L/hr/$^{\circ}C$. Cumulative heat was measued within $\pm$0.2% when testing with a small electri heater submerged in the reactor. Metabolic heat was measured to be 0.76 and 0.76 and 11.4kJ per g consumption of glucose during cultivation of S. cerevisiae and E. coli, respectively.

• Applied Biological Chemistry
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• v.13 no.1
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• pp.97-103
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• 1970

This experiment was carried out to investigate the yeasts for the brewing of soy sauce. The yeasts in the soy sauce koji were isolated and identified. And they were classified by coloring with the treatment of TTC(2, 3, 5 triphenyltetrazolium chloride) agar and counted. The result, obtained was as follows; a) The number of the yeasts in the Koji was increased in process of incubation time: about $97{\times}10^3$ per gram of Koji incubated for 3 days, $135{\times}10^3$ 4 days and $179{\times}10^3$ 5days. b) They were classified as 53.6-71.9 per cent of TTC while yeasts for the most, 5.6-11.1 per cent of red yeasts, 6.8-19.5 per cent of red pink yeasts and 11.1-22.6 per cent of pink yeasts. c) 30 strains of yeasts were isolated from the Koji optionally, and they were identified as 6 genera and 11 species: 5 strains of Saccharomyces rouxii, 2 strains of Saccharomyces fermentati, 1 strain of Saccharomyces rosei, 6 strains of Saccharomyces rosei, 6 strains of Hansenula anomala, 1 strain of Hansenula suaveolens, 6 strains of Pichia polymorpha, 2 strains of Debaryomyces hansenii, 2 strains of Debaryomyces nicotianae, 2 strains of Torulopsis candida 2 strains of Torulopsis sake and 1 strains of Torulopsis sake and 1 strain of Candida pelliculosa. d) The yeasts belonging to Hansenula suaveolens, Hansenula anomala Candida pelliculosa, Debaryomyces nicotianae and Pichia polymorplza were classified as TTC white yeasts, Saccharomyces rouxii and Sacharomyces rosei were red, Saccharomyces fermentati and Debaryomyces hancenii were red pink, and Torulopsis candida and Torulopsis sake were pink. e) Generally the growth of the yeasts isolated were rapid on the media containing none or 10 per cent of sodium chloride but almost restrained on the media containing 15-18 per cent of sodium chloride.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.8
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• pp.1176-1181
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• 2012

This study was conducted to examine changes in the microbial and physicochemical properties of single-brewed Makgeolli in response to high hydrostatic pressure (HHP) treatment during various fermentation stages. HHP was applied in 2-day intervals at 400 MPa for 5 min during fermentation at $25^{\circ}C$. As a result, lactic acid bacteria showed 5~6 log reduction and reappeared at approximately 3~6 log cfu/mL as fermentation proceeded. Yeast also showed 5~6 log reduction but did not reappear during later fermentation period. HPP treatment did not result in any alcohol production on day 0 and 2. However, HPP treatment altered the pH and titratable acidity by reducing the number of microorganism. Reducing sugar contents of the samples increased continuously to 8.99% in 0 day treated sample and 5.01% in 2 day treated sample, whereas untreated Makgeolli contained 1.53% reducing sugars on 6 day due to alcohol conversion by yeast. Based on these results, HPP treatment during various fermentation stages altered the physicochemical properties of Makgeolli by changing the microbial community.

• Microbiology and Biotechnology Letters
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• v.14 no.5
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• pp.359-363
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• 1986

S. diastaticus hydrolysised $\alpha$-1.4 linkage of the starch and was known fermenting yeast strain, but poorly hydrolized $\alpha$-1.6 linkage of the starch. To improve the starch fermentation ability of yeast, we tried that protoplast fusion between S. diastaticus and C. tropicalis and finally two starins of fusant (FPDC42, FPDC43) were obtained. C. tropicalis well hydrolysis both $\alpha$-1.4 and $\alpha$-1.6 linkanges in the starch. The protoplast of parental auxotrophic cells were fused in the presence of 10mM CaCl$_2$ and 35% of polyethylene glycol (M. W. 4,000). The fusion frequency was 10$^{-5}$ to 10$^{-6}$. Properties of the fusants(genetic stability, assimilation of carbon sources, random spore formation, copper resistance, NaCl tolerance, DNA content, cell size and growth rate) were investigated.

• Applied Chemistry for Engineering
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• v.21 no.3
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• pp.349-352
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• 2010

The production process of cellulosic ethanol from rice straw using acidic saccharification was studied in this experimental work. The hydration by ultrasonic energy and the acidic saccharification using 10~30 wt% of $H_2SO_4$ were performed as pretreatment processes. Also, 10~50 wt% of yeast for 3~6 days was used for fermentation process. The yield of cellulosic ethanol was decided in the fermentation process. The optimum pretreatment condition was 375W of ultrasonic power and 30 min of hydration time using 20 wt% of $H_2SO_4$ and 2 h of the acidic saccharification time. Finally, the optimum fermentation condition was at the condition of 30 wt% of yeast and 3 days of fermentation time.

• Microbiology and Biotechnology Letters
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• v.17 no.1
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• pp.8-13
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• 1989

The optimum conditions for ethanol fermentation and ethanol productivity of the fusant ESC-14-15 were examined in a mini-jar formentor scale (working volume : 2.5 liters) to assess the possibility of practical application. Addition of yeast extract to fermentation broth greatly enhanced the ethanol productivity and shortened the period of fermentation. The pH 4.2 was more favorable than pH 5.5 with respect to ethanol productivity and fermentation speed. The optimum concentration of liquefied potato starch for ethanol fermentation of FSC-14-15 was 15%(w/v) and the corresponding productivity was 8.7%(v/v) of ethanol with an efficiency of 80.6% to the theoretical maximum. When the fresh fermentation broth containing 20% of liquefied potato starch was inoculated with love(v/v) of inoculum, the fusant FSC-14-75 produced 11.0%(v/v) of ethanol in 4 days, which is considered comparable to that from an industrial process. From the liquefied cassava starch or the equal mixture of liquefied barley and sweet potato starch prepared according to the same method as in the industrial process except saccharification step, the fusnnt FSC-14-75 produced 8.5%(v/v) or 7.6%(v/v) of ethanol in 4 days, respectively.

• Proceedings of the KAIS Fall Conference
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• 2011.05b
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• pp.1064-1067
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• 2011

술을 안정적으로 제조하기 위하여서는 좋은 밑술을 제조하는 것이 중요하며, 밑술을 제조 하는데 있어서 재료형태에 따라 죽, 구멍떡, 백설기, 고두밥을 만들고, 이를 이용한 밑술을 제조 하였다. 밑술의 제조에 있어서 발효시간, 재료의 형태에 따른 이화학적 성분을 분석하였고, pH는 재료의 형태에 관계없이 24시간 후부터 전부 4이하였으며, 총산은 36시간 까지는 급격히 증가되었다가 유지하는 경향을 나타내었다. 당도는 24시간 까지 증가하였다가 발효에 따라 감소하여 알코올로 전화되는 것을 알 수 있었다. 총당과 환원당도 발효에 따라 알코올로 전화됨으로써 당도와 비슷한 경향을 보였다. 효모수는 초기에는 $9.2{\times}10^6{\sim}3.0{\times}10^7$ CFU/mL 수준 이였고, 죽구의 경우 담금 초기에는 $6.9?{\times}10^6$ CFU/mL 에서 24시간 후에는 $2.1{\times}10^8$ CFU/mL 으로 다른 구 보다 더 상승 하다가 60시간에서 72시간째에는 감소하는 경향을 보였다. 발효 48시간 후 에는 $8.7{\times}10^7{\sim}1.9{\times}10^8$ CFU/mL 수준으로 존재 하였다. 이상의 결과로 48시간부터는 밑술로 사용을 해도 충분하다고 생각된다.