为了筛选1株可用于纯菌种酿造糯米酒的酵母菌,将烧酒曲稀释涂布在淀粉培养基(YPS)平板上培养,得到1株产淀粉酶酵母菌(YW12)。通过形态学、生理生化特征和18S rDNA、ITS区序列分析鉴定,YW12为扣囊复膜酵母(Saccharomycopsis fibuligera)。YW12在YPS液体培养基中28℃培养4 d,用Yoo改良法测其粗酶液的淀粉酶活力为49.8 U/mL。YW12在糯米糖化液(含175 g/L葡萄糖)中28℃发酵3 d的酒精度为5.63%(v/v)。YW12既能同化淀粉又能发酵产生酒精,具有用于纯菌种酿造糯米酒的潜力。

Yeast strain YW12 with amylolytic activity was isolated from rice wine solid starter diluted and spread on starch-degrading plate(YPS agar) to make pure culture starter for rice wine.Based on morphological,cultural and physiological tests and phylogenetic analysis of 18S rDNA and internal transcribed spacer(ITS) sequences,YW12 was identified as Saccharomycopsis fibuligera.Detected with the modified Yoo method,amylase activity of crude enzyme solution from YW12 in YPS broth for 4 days at 28 ℃ was 49.8 U/mL.The strain YW12 cultured in saccharification mash with 170 g/L glucose from glutinous rice for 3 days at 28 ℃ gave 5.63 %(v/v) of ethanol content.Because of its ability of starch-degrading and ethanol fermentation,the strain YW12 maybe have a potential to be used in making defined fungal starter for glutinous rice wine.