盐浓度对蚕豆酱发酵过程中原核微生物多样性及理化因子的影响

Effects of salt concentration on prokaryotic microbial diversity and physicochemical properties during broad bean paste fermentation

蚕豆酱是我国传统的发酵豆类调味品。盐作为一种重要的添加剂,对蚕豆酱的微生物群落结构和品质有着至关重要的影响。为探究不同盐浓度对蚕豆酱发酵过程中原核微生物和理化因子演替规律的影响。采用高通量测序技术对不同发酵时间蚕豆酱的原核微生物多样性进行了分析,并检测了其理化特征。结果表明,盐浓度不仅会显著影响pH、总酸、氨基酸态氮和还原糖的含量,还会显著影响原核微生物的多样性和组成。在不同盐浓度的发酵过程中,厚壁菌门和变形菌门是主要优势菌门,两者相对丰度之和可达97%。在属水平上,葡萄球菌属(34.26%~54.94%)、魏斯氏菌属(11.91%~23.69%)和芽孢杆菌属(8.38%~30.79%)是蚕豆酱发酵过程中的绝对优势细菌属。芽孢杆菌属、盐单胞菌属、片球菌属、盐厌氧菌属、盐乳杆菌属、考克氏菌属和四联球菌属的相对丰度随着盐浓度的升高而升高,呈显著正相关。此外,冗余分析结果表明盐和pH是蚕豆酱发酵过程中原核微生物演替的主要驱动力。该研究解析了盐对蚕豆酱发酵生态的影响,为蚕豆酱生产工艺优化提供了依据。

Broad bean paste(BBP)is a traditional fermented bean condiment in China.As an important additive,salt concentration has crucial effects on the microbial community structure and quality of BBP.To explore the effects of different salt concentrations on the succession of prokaryotic microorganisms and physical and physicochemical factors during the BBP fermentation,the prokaryotic microbial diversity and physicochemical properties during fermentation were investigated by high-throughput sequencing and physicochemical analysis technology.The results showed that salt concentration significantly affected the pH,total acid content,amino acid nitrogen content and reducing sugar content,and the diversity and composition of prokaryotic microbial community as well.Firmicutes and Proteobacteria were detected as the dominant phylum during the fermentation with different salt concentrations,account for 97%of the total relative abundance.At the genus level,Staphylococcus(34.26%-54.94%),Weissella(11.91%-23.69%)and Bacillus(8.38%-30.79%)were the absolute dominant genera during the fermentation of BBP.The relative abundance of Bacillus,Halomonas,Pediococcus,Halanaerobium,Halolactibacillus,Kocuria and Tetragenococcus increased with increasing salt concentration,and there were significant positive correlations between these microorganisms and salt concentration.In addition,the results of redundant analysis showed that salt and pH were the main driving forces for microbial community succession during the fermentation of BBP.This research revealed the effect of salt on the fermentation ecology of BBP,and provided a basis for the optimization of BBP production technology.