Influence of sugar addition in Kombucha production regarding the beverage effect on human fecal microbiota composition and metabolite profile

As kombucha is usually produced by fermenting green tea with sucrose, the present study evaluated the effect of sugar addition in the production process on its claimed prebiotic effect. Kombucha samples without added sucrose (Kombucha), with sucrose (Kombucha_S), and flavored with cashew apple bagasse (Kombucha_CS) were subjected to simulated digestion and fermented with human fecal microbiota for 48 h. Analysis using 16S rRNA sequencing revealed significant changes in microbiota composition. Total phenolic compounds (TPC) decreased by 78.06 % in Kombucha and 35.30 % in Kombucha_S. After fecal fermentation, the Kombucha sample showed the highest concentrations of butyrate , propionate, and acetate, whereas lactate was the main metabolite in Kombucha_S and Kombucha_CS. In the Kombucha sample, the genera Bifidobacterium , Eubacterium , Enterococcus , and Lactobacillus increased by 33.85 %, 12.10 %, 7.93 %, and 2.97 %, respectively. On the other hand, Escherichia-Shigella (57.85 %) and Clostridium XIVa (32.79 %) were predominant in Kombucha_S and Kombucha_CS. Alpha diversity indices, including Shannon and Simpson, indicated increased microbial diversity and species richness in all samples at the end of colonic fermentation. The results showed that kombucha production without added sugar positively influenced intestinal microbiota, promoting increased beneficial bacteria and the production of short-chain fatty acids, thus supporting its potential as a prebiotic beverage. • Compounds in kombucha can alter the intestinal microbiota. • Phenolic compounds are like prebiotics that are commonly utilized by microorganisms. • The change in microbiota depends on the initial relative abundance. • When carbohydrates are absent, the microbiota utilizes organic acids and polyphenols.