鲟鱼发酵过程中微生物的演替变化分析

Bacterial Community Succession Analysis of Fermented Sturgeon at Different Stages

为了解鲟鱼发酵中细菌群落多样性及动态演替规律,为发酵鲟鱼的品质提供理论数据,利用Illumina HiSeq测序平台,采集鲟鱼发酵过程中的7个阶段的样品,对样品中的细菌16S rDNA V4~V5区进行测序和系统发育分析。结果表明,样品获得序列数平均为46 463条,各个发酵阶段的操作分类单元数目分别为新鲜鱼样1 064,腌制鱼样952;发酵5 d 454,发酵10 d 442,发酵20 d 327,发酵25 d 372和发酵35 d 356。7组样品中总体细菌组成较为复杂,含有38个门、196个科,在新鲜鱼样中,厚壁菌门(Firmicutes)和变形菌门(Proteobacteria)占主要优势;在腌制阶段,蓝藻门(Cyanobacteria)占主要优势;从发酵开始至结束,厚壁菌门(Firmicutes)占绝对优势。在科水平上,新鲜鱼样中的主要优势菌科为肠杆菌科(Enterobacteriaceae),腌制样品中的主要优势菌科为肠球菌科(Enterococcaceae);从发酵开始至结束,主要的优势菌科为明串珠菌科(Leuconostocaceae),其次是乳杆菌科(Lactobacillaceae)和链球菌科(Streptococceae)。通过HiSeq测序能够更全面解析鲟鱼发酵过程中的细菌多样性;从测序平台提供的微生物多样性信息中发现,各样品间的菌属丰度存在一定的差异性,说明菌群组成与发酵环境密切相关,这为传统腌鱼发酵提供了理论依据和数据支撑。

In order to investigate the diversity of the bacterial community in fermented fish products , the bacterial community were investigated by 16S rDNA V4-V5 region sequence and phylogenetic relationship analysis using the Illumina HiSeq sequencing platform. The average number of sequences obtained from samples was 46 463. Operational taxonomic units (OTUs) of fresh and salted samples were 1 064 and 952. OTUs of samples fermented for 5, 10, 20, and 25 days were 454, 442, 327, 372, and 356, respectively. The overall bacterial composition of the seven groups samples was complicated,including 196 family in 38 phyla, and Firmicutes was absolutely dominant,followed by Proteobacteria and Cyanobacteria, and the main dominant family were Enterobacteriaceae, Enterococcaceae, Leuconostocaceae, Lactobacillaceae, and Streptococceae.We found that there were diversities in the abundance of bacterial species in each sample and the microfloral composition was closely related to the production process.This method might provide a scientific support for the traditional industry.