预处理对基于扩增子测序技术酒醅微生物菌群结构的影响

Effect of pretreatment on microflora structure of fermented grains based on amplified sequencing technology

磷酸盐缓冲液(PBS)常被用作酒醅预处理,但目前对于预处理前后酒醅菌群结构的改变尚不清晰。采用扩增子测序技术对比分析预处理前后的2种酒醅(酱香型、浓香型)微生物菌群结构变化。结果表明,PBS预处理后两种酒醅真核微生物物种丰度显著增加而原核微生物显著减少(P<0.05),物种种类上无显著改变(P>0.05)。优势真菌及细菌在门水平上组成和相对丰度上均变化较小,但在属水平上组成和相对丰度有明显改变。预处理前后酱香型酒醅真菌属组成相似而细菌属组成有差异;浓香型白酒酒醅真菌属和细菌属均有差异。因此,预处理会在丰度水平上对酒醅微生物菌群结构造成影响,这进一步为酒醅、大曲、窖泥等发酵样品的预处理提供参考价值。

Phosphate buffer solution(PBS)is often used for the pretreatment of fermented grains,but the change of microflora structure of fermented grains before and after pretreatment is not clear.The changes of microflora structure of 2 kinds of fermented grains(sauce-flavor(Jiangxiangxing)and strong-flavor(Nongxiangxing))before and after pretreatment were compared and analyzed by amplicon sequencing technology.The results showed that after PBS pretreatment,the species abundance of eukaryotic microorganisms in two fermented grains increased significantly,while that of prokaryotic microorganisms decreased significantly(P<0.05),and there was no significant change in species(P>0.05).The composition and relative abundance of dominant fungi and bacteria changed little at phylum level,but the composition and relative abundance changed obviously at genus level.Before and after pretreatment,the composition of fungi genera in fermented grains of sauce-flavor Baijiu was similar,while that of bacteria genera was significantly different.The genera of fungi and bacteria in fermented grains of strong-flavor Baijiu were different.Therefore,the pretreatment had an impact on the microflora structure of fermented grains at the abundance level,which further provided reference value for the pretreatment of fermentation samples,such as fermented grains,Daqu,pit mud,etc.