两株耐高温酵母菌的鉴定及其特性研究  

Identification and charateristics of two thermotolerant yeasts

作　　者：宋培勇[1] 曾伯平[1] 肖仲久[1] SONG Pei-yong;ZENG Bo-ping;XIAO Zhong-jiu(College of Biological and Agricultural Science and Technology,Zunyi Normal College,Zunyi 563000,China)

机构地区：[1]遵义师范学院生物与农业科技学院,贵州遵义563000

出　　处：《广东农业科学》2017年第12期79-85,共7页Guangdong Agricultural Sciences

基　　金：贵州省科技厅联合基金(黔科合J字LKZS[2012]25号);贵州省科技创新人才团队项目(黔科合人才团队[2012]4004)

摘　　要：用传统微生物学分离培养方法,从特殊自然环境中筛选耐高温酵母,从形态学、生理生化特征并结合26S r DNA D1/D2区序列比对及系统发育分析对目的菌株进行鉴定,用常规方法对其耐热、耐酸、耐糖和耐乙醇性以及乙醇发酵性能进行测试。结果显示,从常年堆放茅台酒糟的土壤中获得的2株耐高温酵母,经鉴定分别为Y1东方伊萨酵母(Issatchenkia orientalis)、Y2库德毕赤酵母(Pichia kudriavzevii)。耐性测试表明Y1、Y2均能在45℃正常生长,但在46、47℃生长不良,菌落出现异常;初始糖浓度达25%时出现抑制;初始乙醇浓度分别达8%、10%时,Y1、Y2生长受到抑制;最适pH=4。在30、45℃温度条件下,Y1的乙醇产量分别为3.8%和5.1%,Y2分别为8.7%和9.8%,说明Y2的耐乙醇性和乙醇发酵性能较Y1优,具有用于同步糖化发酵的潜能。In order to screen thermotolerant yeasts from special natural environment for ethanol fermentation,we carried out this study.After obtaining the isolates with traditional microbiological methods,we performed idenfication for the isolates according to morphological,physiological and biochemistrial characteristics,integrated26S rDNA D1/D2section sequences comparison and phylogenenitic analysis.Furthermore,we investigated the thermotolerance,acidfastness,sugar tolerance,ethanol tolerance and ethanol yield of the isolates by rutine methods.We obtained two thermotolerant yeasts from the soils for Moutai wine lees stacking,named Y1and Y2.The Y1and Y2were classified to Issatchenkia orientalis and Pichia kudriavzevii,respectively.The tolerance test results showed that isolates Y1and Y2both could survive at45℃,whereas they showed poor growth and abnormal colonies when exceeded45℃.They showed growth inhibility when initial sugar concentration was up to25%,and also the same when initial ethanol concentration was up to8%and10%for Y1and Y2.The optimal pH for them was4.The ethanol yields of Y1and Y2were3.8%and8.7%at30℃,and5.1%and9.8%at45℃,respectively.The ethanol tolerance and fermentation capabilty under the two temperature of30℃and45℃of Y2was more excellent than Y1.So we deduced that the isolate yeast Y1maybe used in simultaneous saccharification and fermentation.

关 键 词：酒糟堆放土壤 耐高温酵母 筛选 鉴定 系统发育分析 耐性测试 

分 类 号：TS261.11[轻工技术与工程—发酵工程]