米粉发酵过程中乳酸菌多样性及功能分析

Analysis of the Diversity and Function of Lactic Acid Bacteria in Fermented Rice Noodles during Fermentation

为了解米粉发酵不同时期的乳酸菌多样性,以5组0~4 d发酵液样品为研究对象,利用高通量测序技术进行乳酸菌多样性和功能预测分析。结果表明,15个样品共得到278个OTU,包括5个门,27个属;整个发酵过程中乳杆菌属(Lactobacillus)占绝对优势,相对丰度均在99%以上。随着发酵时间延长,乳酸菌多样性降低,种水平上0 d有32个种,发酵4 d后仅有12个种。除乳杆菌属外,样品中还有乳球菌属(Lactococcus)和明串珠菌属(Leuconostoc)。PICRUSt功能预测分析表明,不同发酵时期样品均获得氨基酸转运和代谢、碳水化合物转运和代谢、脂质转运和代谢、辅酶转运和代谢、能源产生和转换等与代谢相关的基因。本实验结果为进一步研究乳酸菌对米粉食用品质影响的作用机制,开发米粉专用发酵剂提供理论依据。

In order to investigate the diversity of lactic acid bacteria in fermented rice noodles at different fermentation times,the diversity and functional predication of lactic acid bacteria on days 0,1,2,3 and 4 of fermentation were studied by highthroughput sequencing.The results showed that a total of 278 operational taxonomic units(OTU)belonging to 27 genera in 5 phyla were identified in 15 samples of fermented rice noodles.During the entire fermentation process,Lactobacillus was absolutely dominant,and its relative abundance was over 99%.The diversity of lactic acid bacteria decreased with prolonged fermentation time.There were 32 species detected at 0 day,while only 12 species at 4 days at the species level.In addition to Lactobacillus,Lactococcus and Leuconostoc were also present.PICRUSt gene function prediction showed that the predicted functional genes at different fermentation periods were mainly those involved in amino acid transport and metabolism,carbohydrate transport and metabolism,lipid transport and metabolism,coenzyme transport and metabolism,energy production and conversion,and other metabolism-related genes.This study provides a theoretical rationale for further studying the mechanism of the effect of lactic acid bacteria on the eating quality of fermented rice noodles and for the development of fermentation starters for rice noodle.