利用非培养技术研究古井贡酒大曲中的细菌群落结构

淡雅型白酒古井贡酒大曲中的微生物群落结构一直未在分子水平上得到解析。本文采用构建16s rDNA克隆文库的非培养方法对古井贡酒中温大曲和高温大曲进行细菌群落结构及其多样性研究。所有克隆菌株归为36个OUT,分别属于厚壁菌门(Firmicutes)、变形菌门(Proteobacteria)和一些未培养菌类,其中厚壁菌门占多数。总体来说,中温大曲明显要比高温大曲细菌多样性更丰富一些。高温大曲的菌种相对比较单一,绝大多数为高温放线菌Thermoactinomyces sanguinis,而且仅存在于高温大曲中,占到高温大曲表面菌群的79.5%,高温大曲曲心菌群的98.5%。中温大曲的两个样本差距比较大。样本S1的优势菌为枝芽孢菌属(Virgibacillus sp.),占85.3%,另外还有少量的未培养菌类(12.9%)。中温大曲S2的细菌多样性比较丰富,优势菌属为乳杆菌属Lactobacillus(25.2%)、葡萄球菌属Staphylococcus(14.3%)、芽孢杆菌属Bacillus(13.4%)和各种未培养菌类(16.8%)。古井大曲中存在大量潜在新种,需要进一步鉴定。

Analysis of the Microbial Community Structure of Gujinggong Liquor Starter through Culture-free Approach

Molecular analysis of microbial community structure of GujingGong liquor starter has not been reported so far. 16S rDNA clone library technique was conducted to analysis the bacterial community diversity in high-temperature Daqu and medium-temperature starter of GuJingGong liquor. All clone strains were classified to 36 OTUs, belonging to Firmicutes, Proteobacteria and uncultured bacteria, of which, Firmicutes was the majority. Overall, the bacterial diversity of medium-temperature starter was significantly more complex than that of high-temperature starter. Thermoactinomyces sanguinis accounted for the main majority of the high-temperature starter strains. Bacterial diversity of the two medium-temperature starter samples was apparently different. Dominant bacteria of the sample S1 belong to Virgibacillus sp., accounting for 85.3% in total, in addition to a small amount of uncultured bacteria (12.9%). The dominant bacteria of the sample S2 were Lactobacillus (25.2%), Staphylococcus (14.3%), Bacillus (13.4%) and some uncultured bacteria (16.8%). There are a lot of potential new species that need to be further identified.