Bacterial community and composition in Jiang-shui and Suan-cai revealed by high-throughput sequencing of 16S rRNA.

Fermented vegetables have a long history in many cultures. Jiang-shui and Suan-cai are two of the most well-known instances in North China. They are made by a process of natural lactic acid fermentation. However, they have the different characteristics, i.e. acidity, taste and flavor, which are influenced by the specific bacterial community. Therefore, we used high-throughput sequencing methods to identify the bacterial community structure of Jiang-shui and Suan-cai in this study. Subsequently, we figured out the bacterial differences of these two products using the statistical analysis. Firmicutes and Proteobacteria were the dominant phyla in both Jiang-shui and Suan-cai. However, Lactobacillus was the main genus in Jiang-shui samples, whereas both Lactobacillus and Pediococcus were the major genera in the Suan-cai samples. At the species level, Lactobacillus amylolyticus, Lactobacillus fermentum and Lactobacillus pontis were the major species in Jiang-shui samples, while Pediococcus parvulus, Lactobacillus coryniformis, Lactobacillus pentosus and Lactobacillus parabrevis were the dominant species in the Suan-cai samples. These results suggested that Jiang-shui and Suan-cai had their own unique bacterial community, leading to the specific characteristics. Furthermore, the bacterial communities of both fermented vegetables varied at different locations. This study revealed the flora present in the Jiang-shui and the Suan-cai, providing a deep insight of the microbial species of Chinese fermented vegetables and guidance for the production of the Jiang-shui and the Suan-cai.