Bacterial Diversity of Anshun Sufu, A Traditional Fermented Tofu in Guizhou Province of China

Abstract

Samples of sufu, a traditional food product made by fermenting soybeans, were collected in the city of Anshun in Southwest China and their bacterial diversity was investigated. Nine samples were divided into groups A–C, according to the markets in which they were collected, and the samples were subjected to pyrosequencing of the 16S rRNA V3–V4 regions for evaluation of the bacterial community. A total of 342 operational taxonomic units (OTUs) were determined. One of the samples (B2) included as many as 286 OTUs, and it also displayed the greatest bacterial richness. The most abundant bacterial diversity was shown in group B. Firmicutes was the dominant phylum in groups A and B, while Proteobacteria was the dominant phylum in group C. Lactobacillus was the prevailing genus in group A, Tetragenococcus in group B, and Empedobacter in group C. The bacterial composition of sufu depends, to a large degree, on the manufacturer. The obtained results showed regional differences in the bacterial community patterns of sufu products, which could contribute to a better understanding of the fermentation and ripening bioprocesses of sufu.

Keywords

Sufu / Bacteria / Biodiversity / Sequencing

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