Dynamic changes in microbiota during fermentation of bamboo shoots under varying conditions in Guangxi, China

Jianwen WU ¹ Rong Qin ² Yanyan Lu ³ Gui Qing Li ¹ Xing Fan ^3*

• ¹ Guangxi Forestry Research Institute, Nanning, China
• ² Guangxi Gaofeng State Owned Forest Farm, Nanning, China
• ³ Guangxi Vocational & Technical College, Nanning, Guangxi Zhuang Region, China

The traditional fermentation process for bamboo shoots is long, complex, and yields a product with a non-uniform flavor. To address these issues, we determined the effects of using different parts of the bamboo shoot, different types of fermentation water, water-sealing or not, different types and initial concentrations of organic acids, and different lactobacillus inocula on microbial succession during the fermentation of bamboo shoots. 16S rRNA sequencing was performed using Illumina II high-throughput technology. Species abundance, α-, and β-diversity indices, and linear discriminant analysis effect size (LEfSe) analysis revealed that all detected microorganisms were members of the phyla Firmicutes, Cyanobacteria, and Proteobacteria, of which Firmicutes were dominant. The relative abundance of Firmicutes was higher in water-sealed treatment groups than in non-sealed treatment groups. Different organic acids selected different microbial taxa, and the growth of acid-sensitive Lactococcus and Weissella was inhibited throughout the fermentation period. Different initial organic acid concentrations selected biomarker taxa (Sphingomonas) with the ability to degrade organic pollutants. With tap water as the fermentation broth, Acinetobacter became the dominant bacterial genus, but it inhibited the production of flavor compounds. Streptococcus thermophilus and Lactobacillus bulgaricus from animal sources had no significant effect on fermentation. After inoculation with a five-in-one lactic acid bacteria fermentation agent, the abundance of Clostridium sensu stricto 1 as a biomarker in bamboo shoots was significantly increased, reaching a level 46.6 times that reported in the literature.