Abstract: Zhacai is a popular fermented product made from Brassica vegetable in China. The prokaryotic microbial diversity and physicochemical properties during the fermentation process of Zhacai were investigated using 16S rDNA-based high-throughput sequencing and physicochemical methods. The results showed that the relative abundance of Lactobacillus, which was the dominant genus, increased from 0.92% to 74.77% during fermentation. Leuconostoc could be used as a starter with the relative abundance of 3.61% at the beginning of fermentation, which increased rapidly in the early stage of fermentation and thereafter decreased continuously in the later stage of fermentation. Furthermore, the redundancy analysis showed that the prokaryotic microbial communities were positively correlated with pH value and reducing sugar contents in the early stage of fermentation, and positively correlated with the contents of nitrite, pyruvic acid and succinic acid in the meta stage of fermentation, while they were positively correlated with the levels of total acid and other organic acids (malic acid, tartaric acid, citric acid, oxalic acid, acetic acid, lactic acid) in the later stage of fermentation. The successions of prokaryotic microbial communities and its influencing factors were systematically studied in this work, which could be a theoretical basis for further precise artificial regulation and data reference for screening characteristic strains.
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