Abstract: An artificial microbial consortium was constructed by using four dominant strains isolated from tea fungus. Through comparison of single and mixed cultures, we determined the role of these strains in the fermentation of tea fungus and the formation of biofilm. High performance liquid chromatography (HPLC) and headspace solid-phase microextraction (HS-SPME) coupled to gas chromatography-mass spectrometry (GC-MS) were used to analyze the major biochemical components in the fermentation process of tea fungus. After multiple passages, the stability of the microbial consortium was analyzed using a combination of isolation and metagenomic analysis. The results showed that among the four strains tested, Gluconacetobacter sp. J5 was the core strain producing cellulose and biofilm. The fermentation characteristics of the synthetic microbial consortium was comparable to natural fermentation in terms of cell growth, sugar utilization, pH, total acidity and tea polyphenol content. The microbial consortium was stable and all four strains were dominant in the microbial consortium after six passages. These results suggest that the functional strains isolated from tea fungus can be used to construct a stable artificial starter culture, which will lay the foundation for the standardized industrial production of tea fungus.

Key words: tea fungus; mixed microbial cultures; biochemical components; core strains; microflora stability