基于PLFA指纹图谱表征浓香型酒糟醅微生物群落结构

以9株白酒酿造过程中常见的菌株为对象,研究了不同种属菌株的细胞膜特征组分磷酸脂肪酸(PLFA)的特征,以及检出量与菌株生物量之间的关系.结果表明:供试细菌、放线菌、霉菌和酵母菌的PLFA指纹图谱存在显著差异,各菌株的PLFA指纹图谱可作为区别种属的依据.不同供试菌株生物量在一定范围内与检出的总PLFA量或16:0含量呈线性关系.将不同生物量的革兰氏阳性菌G+、革兰氏阴性菌G-和真菌分别加入糟醅后,检出的PLFA相对含量与对照差异显著.基于PLFA的指纹图谱能够定量或半定量地表征糟醅微生物群落结构特征及动态变化.经对多家酿酒企业糟醅PLFA组成的检测及微生物群落结构的剖析,该方法具有普适性.

Microbial community structure in strong aromatic liquor fermented grains characterized by PLFA fingerprints

Taking the nine common microbial strains in liquor-making process as test objects, this paper studied the characteristics of phospholipid fatty acid (PLFA), a characteristic component of the strains cell membrane, and the relationships between the detected amount of PLFA and the biomass of the strains. There existed significant differences in the PLFA fingerprints between test bacteria, actinomycetes, molds, and yeasts, and the PLFA fingerprint of each strain could be used as the basis to distinguish species and genus. Within a certain range of the strains biomass, the detected amount of total PLFA or 16:0 was linearly correlated with the biomass. After adding different biomass Gram positive (G+) bacteria, Gram negative (G-) bacteria, and fungi in fermented grains, a significant difference was observed in the relative amount of PLFA between experimental and control samples. It was suggested that the fingerprint of PLFA could quantitatively or semi-quantitatively characterize the microbial community structure and its dynamic variation in fermented grains. By detecting the PLFA profiles of fermented grains in various liquor industries and by analyzing the microbial community structure in the fermented grains, it was substantiated that PLFA fingerprinting was of general applicability.