Abstract: In order to investigate the bioactive ingredients and microbial diversity of Fuzhuan tea produced from different raw materials, the bioactive ingredients of Fuzhuan tea produced from Anhua black tea, Dianhong black tea, Eucommia ulmoides leaves or dandelion under identical conditions were detected, respectively. Additionally, the microbial community structure was determined by high-throughput sequencing, and correlation analysis between the microbial community structure and the bioactive ingredients was further performed. The results showed that there was a significant difference in the contents of bioactive ingredients among the four tested samples, but no significant difference was found in the fungal community structure at the genus level. Aspergillus was the absolutely dominant group with a relative abundance of over 99.99% in all tested samples. The bacterial communities were abundant in the four samples, consisting of 30 genera in 9 phyla, and a significant difference in bacterial community structure was found. Interestingly, at the level of phylum, Proteobacteria was the dominant bacterium in all tea samples. However, at the genus level, the bacterial community in the sample produced from Anhua black tea was mainly composed of unclassified_f__Enterobacteriaceae and Pseudomonas. In the sample produced from Eucommia ulmoides leaves, Pseudomonas showed the highest abundance. In the sample produced with Dianhong black tea, Burkholderia-Caballeronia-Paraburkholderia was the most abundant. In the product produced from dandelion, Allorhizobium-Neorhizobium-Pararhizobium-Rhizobium was the most abundant. In addition, Pseudomonas and Burkholderia-Caballeronia-Paraburkholderia appeared in higher abundance in the four samples. The correlation analysis indicated that unclassified_f__Enterobacteriaceae was positively correlated with polyphenol, catechin, epicatechin, epigallocatechin and gallic acid. Pseudomonas was positively correlated with flavonoid, whereas Burkholderia-Caballeronia-Paraburkholderia was negatively correlated with epigallocatechin gallate, and all these correlations were statistically significant (P < 0.05). This study provides a deeper understanding of the microbial diversity in Fuzhuan tea produced from different raw materials and provides the basis for the development of new products of Fuzhuan tea.

Key words: Fuzhuan tea; bioactive ingredients; high-throughput sequencing; microbial diversity