Microbial Diversity During Fermentation Of Traditional Dajiang In Northeast Of China

Soybean paste is an ancient spice of our country,due it is rich in nutrition,aroma,unique taste,deeply loved by the people.But the current researches on the traditional soypaste mainly focus on the physical and chemical indexes,rheological properties,texture and flavor extraction evaluation etc.Therefore,in-depth study of traditional soybean paste at different fermentation stage of microbial diversity,grasp its growth pattern has important significance to improve the quality of soybean industry,optimization of improved strains and realized industrialization development.In this study,the diversity and dynamic changes of the bacteria during fermentation state of Dajiang was analyzed by using denaturing gradient gel electrophoresis(DGGE)technology and High throughput sequencing.Composition analysis can be obtained at different fermentation stage Dajiang microbial community using DGGE method:There were 3 bacteria genera and 7 fungi genera identified of the Dajiang sample in T.Enterococcus,Lactobacillus and Tetragenococcus were the dominant bacteria genera.Geotrichum was the dominant fungi genera.There were 5 bacteria genera and 5 fungi genera identified of the Dajiang sample in Z,and Lactobacillus was the dominant bacteria genera.Geotrichum was the dominant fungi genera.There were 9 bacteria genera and 3 fungi genera identified of the Dajiang sample in S.Leuconostoc was the dominant bacteria genera and Geotrichum was the dominant fungi genera.The Dajiang samples by Illumina Miseq high-throughput sequencing to microbial communities in different fermentation stages in Dajiang composition,after finishing the analysis:The Dajiang samples identified 5 known bacteria phyla,3 known fungi phyla,the Firmicutes and Proteobacteria were the dominant bacteria phyla in the fermentation process,and Ascomycota was the dominant fungi phyla.All samples of Dajiang identified 100 known bacteria genera and 61 known fungi genera.Tetragenococcus,Enterococcus and Leuconostoc were the dominant bacteria gener a of the Dajiang sample in T.Their average contents were 56.20%,14.25%and 8.28%,respectively.Penicillium,Aspergillus and Geotrichum were the dominant fungi ge ne-ra of the Dajiang sample in T.Their average contents were 30.6%,16.05%and 6.32%.Leuconostoc and Tetragenococcus were the dominant bacteria genera of the Dajiang sample in Z.Their average contents were 19.43%and 9.76%.Penicillium,Candida and Geotrichum were the dominant fungi genera of the Dajiang sample in Z.Their average contents were 17.40%,10.83%and 6.55%.Acinetobacter,Leuconostoc and Pseudomonas were the dominant bacteria genera of the Dajiang sample in S,and their average contents were 18.76%,16.24%and 7.38%.Penicillium,Neurospora,Rhizopus were the dominant fungi genera of the Dajian g sample in S,and their average contents were 46.60%,3.60%and 3.42%.The average content of Leuconostoc were relatively large,it was the dominant bact-eria genera of the Dajiang sample in three families in Liaoning.The average content of Penicillium and Geotrichum were relatively large.This experiment through DGGE molecular biology techniques combined with high-t hroughput sequencing method,systematic research on microorganism community of tra ditional natural fermented Dajiang,reveal the microbial community structure in differe nt periods of the real state.Provide the basis for the realization of modernization of t he traditional Dajiang,large-scale production,further research and development of goo d strains of naturally fermented Dajiang.