• Microbiology and Biotechnology Letters
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• v.10 no.2
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• pp.95-100
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• 1982

Torulopsis candida FRI YA-15, a selected yeast, was cultivated in alcohol distiller's waste-filtrate of dried sweet potato for microbial protein production and BOD reduction. The General composition of waste-filterate was BOD$_{5}$ 15700 ppm, COD 36800 ppm, reducing sugar 3300 ppm, total nitrogen 910 ppm, total solids 51800 ppm and ash 390 ppm. The pH of waste was 3.85. The yield to the medium of T. candida cultivated in shake-flask at $25^{\circ}C$ for 48 hrs was 3.38g/$\ell$ and effectiveness in reducing BOD$_{5}$ and COD of waste was 38.9% and 31.8%, respectively. In batch cultivation using 3 $\ell$-jar fermenter, maximum yield to the medium reached 3.2g/$\ell$after 28 hrs cultivation under the condition of temperature 35$^{\circ}C$, initial pH 4.0, aeration rate 2vvm, agitation speed 100rpm. Dry yeast was composed of crude protein 47.98% and ash 5.23%.

• Proceedings of the Korean Society for Applied Microbiology Conference
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• 1976.10a
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• pp.188.1-188
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• 1976

주유소, 공장주변의 하수 및 토양으로부터 Methanol 자화성 효모 7주를 분리하고 그중 생육이 왕성한 균주 2주에 대하여 동정을 행한즉 양주, 모두 Candida속에 속하는 것으로 추정되었다. 양주는 모두 ethanol 자화성을 가지고 생육에는 Biotin을 요구하였다. 배양특성은 최적온도 $28^{\circ}C,$ 최적 pH4~5이고 methanol 농도 1% v/v에서 증식이 양호하였고, 균체수율은 대소비 methanol에 대하여 30~40%에 달하였다.

• Proceedings of the Korean Society for Applied Microbiology Conference
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• 1979.10a
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• pp.245.1-245
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• 1979

PDP 전자 계산기를 발효소에 연결하여 자동 제어하의 효모 유가 배양을 수행하였다. 필요한 부대 장치들을 만들어 성공적으로 사용하고 feed-back자동 제어를 수행할 수 있게 발효도중 임의의 시간에 발효 조건을 모니터하도록 하였다. 연속 세포 농도 측정을 위한 플로우ㆍ셀을 자체 제작하여 사용함과 동시에 기포 제거를 따로 할 필요가 없도록 하였다. 측정 시그날을 위한 증푹기도 자체 제작하였던 바 우수한 성능을 보여 주었다. 이 경험으로 다른 모든 측정 장치의 개발과 전자 계산기에의 연결에 값진 경험을 주었다.

• KSBB Journal
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• v.11 no.4
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• pp.445-452
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• 1996

To investigate the promoter effect on heterologous gene expression in S. cerevisiae, the recombinant plasmids pYI11, pYI12, pYI10-2, and pYIGP were constructed to contain the inulinase gene (INUI) as a reporter under the control of GAL10, GAL7, GAL1, and GAP promoters, respectively. When the yeasts transformants were cultivated on galactose-containing rich media, the cell growth reached to 36-39 OD600 at 72 hours of cultivation. The specific growth rates of the cells harboring the four different plasmids decreased similarly : they dropped from $0.24 h^{-1}$ during the glucose-consuming period to 0.04 -$0.10 h^{-1}$ during the galactose-consuming period (gene expression phase for GAL promoter system). After the depletion of glucose, the expression of inulinase gene was started and reached to maximal levels of 4.3(GAL1 promoter), 4.0(GAL10 promoter), 3.8(GAL7 promoter), and 1.6(GAP promoter) unit/mL at 72 hours of cultivation. Based on the maximal expression level and activity staining on the plate, the promoter strength was in the order of GAL1, GAL10, GAL7 and GAP promoter. While the GAL-promoter systems showed a high plasmid stabilities of more than 78%, the GAP-promoter plasmid revealed a lower plasmid stability of 55%. Most of inulinase activity (98%) was found in the extracellular medium, indicating that the secretion efficiency of inulinase is independent on the type of promoter.

• Journal of Food Hygiene and Safety
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• v.2 no.1
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• pp.15-20
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• 1987

A general screening test for the expression of antioxidative activity was performed on over 36 cultures belong to yeast isolated from soy sauce, Makkuli, and molasses. Antioxidative activities of yeasts were examined by measuring oxidation such as peroxide value and thiobarbituric acid value in fish oil. Of these cultures, Saccharomyces cerevisiae IFO 2114 were found to have strong antioxidative activity. Saccharomyces rouxii and Torulopsis etchellsii isolated from soy sauce showed the strongest antioxidative activity among yeasts. Pichia ohmerii isolated from Makkuli showed the strongest antioxidative activity and Candida versatilis isolated from molasses showed also relative strong antioxidative activity.

• Journal of the Korea Organic Resources Recycling Association
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• v.9 no.1
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• pp.49-55
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• 2001

For the production of probiotic feed enriched with viable yeasts, aerobic liquid culture of Kluyveromyces marxianus was attempted in pulverized residual food wastes. After the preliminary shaking culture result, the liquid food wastes was added with urea($0.5g/{\ell}$), o-phosphate($0.4g/{\ell}$ ), molasses($4g/{\ell}$), and yeast extract($1g/{\ell}$), and the fermentation was carried out in 2-litre jar fermenter. In 12 hours of aerobic mixed culture with Aspersillus oryzae, viable cell count of the yeast reached to the number of $1.4{\times}10^{10}/{\ell}$ in the cultured medium.

• Microbiology and Biotechnology Letters
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• v.17 no.6
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• pp.619-623
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• 1989

The effects of temperature on yeast growth and ethanol production were investigated in batch cultures. The maximum specific growth rate of yeast was obtained at 36$^{\circ}C$ and the maximum specific production rate of ethanol was obtained at 33$^{\circ}C$. A mathematical model was employed to describe the temperature effects in ethanol fermentation and the parameters in the model were expressed as a function of temperature. Optimum temperature control strategy, from the simulation result, consists of starting the fermentation at high temperature and lowering the temperature as the fermentation proceeds.

• Applied Biological Chemistry
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• v.23 no.1
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• pp.64-72
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• 1980

Industrial wastes from pulp and food plants were treated with microorganisms to clarify organic waste-water and to produce cells as animal feed, and results were summarized as follows. (1) Waste-water from pulp, beer, bread yeast, and ethanol distillation plants contained $1.4{\sim}1.5%$ of total sugar, $0.25{\sim}0.35%$ nitrogen, and biological oxygen demand (BOD) was $400{\sim}25,000$, chemical oxygen demand (COD), $500{\sim}28,000$, and pH, $3.8{\sim}7.0$. The BOD and COD were highest in waste-water from ethanol distillation plants among others. (2) Bacterial and yeast counts were $4{\times}10^4-1{\times}10^9,\;2{\times}10^2-7{\times}10^4/ml$ in waste-water. (3) Bacteria grew better in pulp waste and yeasts in beer, bread yeast, and ethanol distillation waste. (4) Saccharomyces cerevisiae SAFM 1008 and Candida curvata SAFM 70 were the most suitable microorganisms for clarification of ethanol distillation waste. (5) When liquid and solid waste from ethanol distillation were treated with microbial cellulase, xylanase, and pectinase, solid waste was reduced by 36%, soluble waste was increased, and recuding sugar content was increased by 1.3 times which provided better medium than untreated waste for cultivation of yeasts. (6) Optimum growth conditions of the two species of yeast in ethanol distillation waste were pH 5.0, $30^{\circ}C$, and addition of 0.2% of urea, 0.1% of $KH_2PO_4$ and 0.02% of $MgSO_4$. (7) Minimum number of yeast for proper propagation was $1.8{\times}10^5/ml$. (8) C. curvata70 was better than cerevisae for the production of yeast cells from ethanol distillation waste treated with microbial enzymes. (9) S. cerevisiae produced 16 g of dried cell per 1,000ml of ethanol distillation waste and reduced BOD by 46%. C. curvata produced 17.6g of dried cell and reduced BOD by 52% at the same condition. (10) Yeast cells produced from the ethanol distillation waste contained 46-52% protein indicating suitability as a protein source for animal feed.

• KOREAN POULTRY JOURNAL
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• v.23 no.9 s.263
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• pp.155-157
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• 1991

• KOREAN POULTRY JOURNAL
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• v.28 no.2 s.316
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• pp.179-185
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• 1996