Seo Sung-Hee, Rhee Chang-Ho, Park Heui-Dong
Department of Life and Food Sciences, College of Agriculture and Life Sciences, Kyungpook National University, Daegu, Republic of Korea.
J Microbiol. 2007 Dec;45(6):521-7.
Several yeast strains degrading malic acid as a sole carbon and energy source were isolated from Korean wine pomace after enrichment culture in the presence of malic acid. Among them, the strain designated as KMBL 5774 showed the highest malic acid degrading ability. It was identified as Issatchenkia orientalis based on its morphological and physiological characteristics as well as the nucleotide sequences of the internal transcribed spacer (ITS) I-5.8S rDNA-ITS II region. Phylogenetic analysis of the ITS I-5.8S rDNAITS II sequences showed that the KMBL 5774 is the closest to I. orientalis zhuan 192. Identity of the sequences of the KMBL 5774 was 99.5% with those of I. orientalis zhuan 192. The optimal pH of the media for the growth and malic acid degradation by the yeast was between 2.0 and 3.0, suggesting that the strain is an acidophile. Under the optimized conditions, the yeast could degrade 95.5% of the malic acid after 24 h of incubation at 30 degrees in YNB media containing 2% malic acid as a sole carbon and energy source.
在以苹果酸为唯一碳源和能源的富集培养后，从韩国葡萄酒渣中分离出了几种以苹果酸为唯一碳源和能源的酵母菌株。其中，命名为KMBL 5774的菌株表现出最高的苹果酸降解能力。根据其形态和生理特征以及内部转录间隔区（ITS）I-5.8S rDNA-ITS II区域的核苷酸序列，它被鉴定为东方伊萨酵母。对ITS I-5.8S rDNAITS II序列的系统发育分析表明，KMBL 5774与东方伊萨酵母zhuan 192最为接近。KMBL 5774的序列与东方伊萨酵母zhuan 192的序列一致性为99.5%。该酵母生长和降解苹果酸的培养基最适pH在2.0至3.0之间，表明该菌株是嗜酸菌。在优化条件下，该酵母在含有2%苹果酸作为唯一碳源和能源的YNB培养基中于30℃培养24小时后，可降解95.5%的苹果酸。
