沙棘酵素自然发酵过程中品质特征和细菌群落动态变化

为揭示沙棘酵素发酵过程中细菌菌群结构演变规律及自然发酵本质，利用Illumina Miseq高通量测序技术分析发酵过程中细菌群落结构的变化，同时对其各项理化指标和活性成分的变化规律进行分析。结果表明，经过60 d自然发酵，pH由4.42下降至3.47，总酸由2.6 g/L增加至10.54 g/L，总糖由80.69 g/L下降至32.59 g/L，可溶性性蛋白由0.87 g/L下降至0.28 g/L，而总黄酮和总多酚分别由0.11 g/L和1.24 g/L增加至0.47 g/L和4.55 g/L。沙棘酵素发酵过程中细菌群落的物种多样性整体呈逐渐下降的变化趋势。在整个发酵过程中，厚壁菌门（Firmicutes）和变形菌门（Proteobacteria）是主要优势菌门，其相对丰度之和大于97%。乳杆菌属（Lactobacillus）是发酵后期的绝对优势属，其发酵60 d的相对丰度可达82.16%。此外，冗余分析结果表明pH和总酸是沙棘酵素发酵过程中细菌群落演替的主要驱动力。该研究加深对自然沙棘酵素发酵机制的认识，为筛选潜在价值的益生菌和实现精准人工调控提供科学依据。

Quality Changes and Bacterial Community Dynamics of Sea Buckthorn Jiaosu during Nature Fermentation

In order to reveal the evolution of bacterial flora during the natural fermentation process of sea buckthorn jiaosu, changes in the bacterial community structure of fermentation were analyzed by Illumina Miseq high-throughput sequencing technique. Moreover, changes in physicochemical indexes and active components were also monitored. The results showed that after 60 days of natural fermentation, pH decreased from 4.42 to 3.47, total acid increased from 2.6 g/L to 10.54 g/L, total sugar decreased from 80.69 g/L to 32.59 g/L, and soluble protein decreased from 0.87 g /L decreased to 0.28 g/L, while total flavonoids and total polyphenols increased from 0.11 g/L and 1.24 g/L to 0.47 g/L and 4.55 g/L, respectively. A gradual decline trend in species diversity of the bacterial community was observed during the sea buckthorn jiaosu fermentation. Firmicutes and Proteobacteria were detected as the main advantage phylum during the whole fermentation process, and the sum of their relative abundance was greater than 97%. Lactobacillus was the absolute dominant genus in the late fermentation stage, and its relative abundance was reached 82.16% after 60 days of fermentation. In addition, the results of redundant analysis showed that pH and total acid content were found to be the main driving force of microbial community succession during the fermentation process of sea buckthorn jiaosu. This research may deepen the understanding of the mechanism in nature fermentation of sea buckthorn jiaosu, and provide a scientific basis for screening potentially valuable probiotics and realizing precise artificial regulation .