• 한국식품과학회지
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• 제14권4호
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• pp.394-396
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• 1982

발효로부터 생성되는 에타놀에 의해서 균체성장속도가 제한되는 연속식 배양 시스템에서, 에타놀 생성균주인 Saccharomyces uvarum과 Zymomonas mobilisrks의 경쟁적 상호 작용을 연구한 결과 Zymomonas mobilis가 Saccharomyces uvarum에 비하여 에타놀에 대한 내성(耐性)이 크기 때문에 Zymomonas mobilis 만이 생존할 수 있다.

• Journal of Microbiology and Biotechnology
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• 제1권3호
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• pp.151-156
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• 1991

In order to construct a yeast strain having high ethanol tolerance together with good lactose fermentation ability, the protoplast fusion using Saccharomyces cerevisiae STV 89 and Kluyveromyces fragilis CBS 397 was carried out. Auxotrophic mutants of K. fragilis were obtained as a selection marker by treatment of ethylmethane sulfonate. The best mutant for protoplast fusion was selected based on the capabilities of ${\beta}-galactosidase$ production and lactose fermentation. The protoplast fusion using polyethylene glycol and calcium chloride solution led to the fusion frequence of $3{\times}10^{-6}$ and a number of fusants were obtained. Among these fusants, a fusant F-3-19 showed the best results in terms of ethanol tolerance, ${\beta}-galactosidase$ activity and lactose fermentation. The performance of lactose fermentation and ethanol tolerance by this fusant were better than those of K. fragilis. Study on the ethanol tolerance having relation to fatty acid composition and intracellular ethanol concentration revealed that the fusant F-3-19 had a higher unsaturated fatty acids content and accumulated less amount of intracellular ethanol compared with a parent of K. fragilis.