茅台镇酱香白酒不同轮次主酿区可培养霉菌种群结构多样性

Structure and Diversity of Culturable Mold Communities in Different Fermentation Rounds in Main Maotai-Flavored Liquor-Brewing Areas of Maotai Town

在前期利用宏基因组学系统分析微生物种群结构的基础上,利用传统培养方法及18S rRNA基因测序,对茅台镇酱香白酒酿造的7个不同轮次主要酿造区域环境和大曲中可培养霉菌种群结构多样性进行研究,分别分离得到614株和486株霉菌,通过形态和18S rRNA基因测序比对分析,共送检256株霉菌,最终从环境样品中鉴定得到27个属57个种不同霉菌,大曲样品中鉴定得到15个属31个种不同霉菌。通过对不同酿造轮次环境和大曲中可培养霉菌多样性结构分析,明确了Lichtheimia、Mucor、Aspergillus、Monascus、Rhizomucor、Paecilomyces、Schizophyllum等属是酱香白酒酿造环境中具有绝对优势的霉菌;Lichththeimia、Aspergillus、Penicillium、Phanerochaete、Thermoascus等属是酱香白酒酿造大曲中具有绝对优势的霉菌;通过对轮次间种群结构差异性分析、酿造环境和大曲中霉菌种群结构差异性分析,对比霉菌在各轮次的消涨变化、消亡率和富集率高低,深入剖析了酿造环境和大曲中霉菌对酱香白酒发酵的重要意义,从微生物角度诠释了高温大曲和堆积发酵都是酱香白酒中不可分割的酿造工艺。

Based on our previous study on metagenomic analysis of microbial community structure,the structure and diversity of culturable mold communities in Daqu and environmental samples from 7 different fermentation rounds in the main Maotai-flavored liquor-brewing areas of Maotai town,Guizhou were investigated by traditional culture method and18 S rRNA gene sequencing.A total of 614 and 486 strains of mold were isolated from the Daqu and environmental samples,respectively and out of these,256 strains were selected for further analysis by morphological features and 18 S rRNA gene sequencing analysis.Finally,57 mold species belonging to 27 genera were identified from the environmental samples.In the Daqu samples,31 mold species in 15 genera were identified.Lichtheimia,Mucor,Aspergillus,Monascus,Rhizomucor,Paecilomyces,and Schizophyllum were the dominant molds in the brewing environment,while Lichtheimia,Aspergillus,Penicillium,Phanerochaete,and Thermoascus were the dominant molds in Daqu.This study confirmed the significance of molds in the brewing environment and Daqu for the fermentation of Maotai-flavored liquor,and highlighted that hightemperature Daqu and stacking fermentation are both indispensable for the production of Maotai-flavored liquor.