Sequence-based analysis of the bacterial and fungal compositions of multiple kombucha (tea fungus) samples
Alan J. Marsh, Orla O'Sullivan, Colin Hill, R. Paul Ross, Paul D. Cotter
Kombucha is a sweetened tea beverage that, as a consequence of fermentation, contains ethanol, carbon dioxide, a high concentration of acid (gluconic, acetic and lactic) as well as a number of other metabolites and is thought to contain a number of health-promoting components. The sucroseetea solution is fermented by a symbiosis of bacteria and yeast embedded within a cellulosic pellicle, which forms a floating mat in the tea, and generates a new layer with each successful fermentation. The specific identity of the microbial populations present has been the focus of attention, but, to date, the majority of studies have relied on culture-based analyses. To gain a more comprehensive insight into the kombucha microbiota, we have carried out the first culture-independent, high-throughput sequencing analysis of the bacterial and fungal populations of 5 distinct pellicles as well as the resultant fermented kombucha at two time points. Following the analysis, it was established that the major bacterial genus present was Gluconacetobacter,present at >85% in most samples, with only trace populations of Acetobacter detected (<2%). A prominent Lactobacillus population was also identified (up to 30%), with a number of sub-dominant genera, not previously associated with kombucha, also being revealed. The yeast populations were found to be dominated by Zygosaccharomyces at >95% in the fermented beverage, with a greater fungal diversity present in the cellulosic pellicle, including numerous species not identified in kombucha previously.Ultimately, this study represents the most accurate description of the microbiology of kombucha to date.
Keywords: kombucha, sequencing, tea fungus, tea, 16s, its
Citation: Food microbiology, 38, 171-178.
Study Mailing Address:
Teagasc Food Research Centre, Moorepark, Fermoy, Co.
Date Updated: January 26, 2021