贵州浓香型白酒大曲中霉菌的18S rDNA系统发育分析

Phylogenetic Analysis of 18S rDNA Sequence of Mold from Luzhou-flavor Daqu

从贵州某名酒厂大曲中分离到104株丝状真菌(霉菌),通过形态特征和生理特性检测等传统鉴定方法,初步把形态和生理生化特征一致的霉菌归类为14个大类群;并采用18S rDNA序列分析,进一步把菌株归类为MJ-Ⅰ至MJ-Ⅴ五个类群,随后构建系统发育树.结果表明,样品中的霉菌以曲霉属(Aspergillus)为主,占总分离菌数的40.38%;犁头霉属(Absidia)也占有相当的比例,达到31.73%;还有16.35%的假埃希氏菌属(Pseudallescheria)、6.73%的茎点霉属(Phoma)以及4.80%的拟青霉属(Paecilomyces).其中,假埃希氏菌属菌株在相似生态环境中还未见公开报道.MJ-Ⅰ菌群的代表菌株MJ-10与烟曲霉(Aspergillus fumigatus)的相似度达到了99%,MJ-Ⅴ菌群的代表菌株MJ-11与伞枝犁头霉(Absidia corymbifera)的相似度达到100%,表明菌株MJ-10和菌株MJ-11已经鉴定到了种.研究表明,在生态环境有差异的情况下,大曲中微生物的多样性既有相似性,也有所差异,这是贵州浓香型白酒区别于其他地方浓香型白酒的一个重要原因,同时也为贵州浓香型白酒的个性化和品质提升提供了理论依据.

104 strains of filamentous fungi were isolated from Daqu of a famous distillery in Guizhou,and classified into fourteen groups based on their morphological and physiological characteristics,and then categorized into five groups（MJ-Ⅰ,MJ-Ⅱ,MJ-Ⅲ,MJ-Ⅳ,MJ-Ⅴ） by 18S rDNA sequence comparison,at last the phylogenetic tree was reconstructed.The results showed that Aspergillus accounted for 40.38% of the molds in number,Absidia 31.73%,Pseudallescheria 16.35%,Phoma 6.73% and Paecilomyces 4.80%.Pseudallescheria had not been reported publicly in similar ecological environment before.The representative strain MJ-10 in MJ-Ⅰflora had very high similarity of 99% to Aspergillus fumigatus and the 18S rDNA gene sequence of strain MJ-11 in MJ-Ⅴ flora was 100% similar to Absidia corymbifera,which demonstrated that strains MJ-10 and MJ-11 were identified to species accurately.The study indicated that there were similarities and differences among microbial diversities of Daqu from different ecological environments,which resulted in unique quality of the liquors.Fig 2,Tab 1,Ref 17