Determination and Characterization of the Antimicrobial Activity of the Fermented TeaKombucha

Abstract

Early reports onKombucha, a traditional fermented tea beverage, suggested that it has antimicrobial activity against a spectrum of organisms, and that concentrates of unfermented tea components also have anti microbial properties. Therefore, the focus of this study was to determine and characterizeKombucha'santimicrobial activity using an absorbent disc method. Antimicrobial activity was observed in the fermented samples containing 33 g/L total acid (7 g/L acetic acid) against the tested Gram-positive and Gram-negative organisms (Agrobacterium tumefaciens, Bacillus cereus, Salmonella choleraesuisserotypetyphimurium, Staphylococcus aureus, andEscherichia coli.Candida albicanswas not inhibited byKombucha. The contribution of tea itself to the antimicrobial activity ofKombuchaproved to be significant in the tested organisms, even at the highest levels tested, 70 g/L dry tea. As a result, the antimicrobial activity ofKombuchawas attributed to its acetic acid content.