title: Antibacterial Activity of Polyphenolic Fraction of Kombucha Against Enteric Bacterial Pathogens.
abstract: The emergence of multi-drug-resistant enteric pathogens has prompted the scientist community to explore the therapeutic potentials of traditional foods and beverages. The present study was undertaken to investigate the efficacy of Kombucha, a fermented beverage of sugared black tea, against enterotoxigenic Escherichia coli, Vibrio cholerae, Shigella flexneri and Salmonella Typhimurium followed by the identification of the antibacterial components present in Kombucha. The antibacterial activity was evaluated by determining the inhibition zone diameter, minimal inhibitory concentration and minimal bactericidal concentration. Kombucha fermented for 14 days showed maximum activity against the bacterial strains. Its ethyl acetate extract was found to be the most effective upon sequential solvent extraction of the 14-day Kombucha. This potent ethyl acetate extract was then subjected to thin layer chromatography for further purification of antibacterial ingredients which led to the isolation of an active polyphenolic fraction. Catechin and isorhamnetin were detected as the major antibacterial compounds present in this polyphenolic fraction of Kombucha by High Performance Liquid Chromatography. Catechin, one of the primary antibacterial polyphenols in tea was also found to be present in Kombucha. But isorhamnetin is not reported to be present in tea, which may thereby suggest the role of fermentation process of black tea for its production in Kombucha. To the best of our knowledge, this is the first report on the presence of isorhamnetin in Kombucha. The overall study suggests that Kombucha can be used as a potent antibacterial agent against entero-pathogenic bacterial infections, which mainly is attributed to its polyphenolic content.
authors.affiliation: Department of Life Science & Biotechnology, Jadavpur University, 188 Raja S.C. Mullick Road, Kolkata, 700032, India.
authors.forename: Debanjana
authors.initials: D
authors.lastname: Bhattacharya
authors.affiliation: Department of Life Science & Biotechnology, Jadavpur University, 188 Raja S.C. Mullick Road, Kolkata, 700032, India.
authors.forename: Semantee
authors.initials: S
authors.lastname: Bhattacharya
authors.affiliation: Department of Life Science & Biotechnology, Jadavpur University, 188 Raja S.C. Mullick Road, Kolkata, 700032, India.|Department of Microbiology, Bose Institute, P1/12 C.I.T. Scheme VIIM, Kolkata, 700054, India.
authors.forename: Madhu Manti
authors.initials: MM
authors.lastname: Patra
authors.affiliation: Department of Life Science & Biotechnology, Jadavpur University, 188 Raja S.C. Mullick Road, Kolkata, 700032, India.|Department of Biochemistry and Molecular Biophysics, Kansas State University, Manhattan, KS, USA.
authors.forename: Somnath
authors.initials: S
authors.lastname: Chakravorty
authors.affiliation: Department of Life Science & Biotechnology, Jadavpur University, 188 Raja S.C. Mullick Road, Kolkata, 700032, India.
authors.forename: Soumyadev
authors.initials: S
authors.lastname: Sarkar
authors.affiliation: Department of Life Science & Biotechnology, Jadavpur University, 188 Raja S.C. Mullick Road, Kolkata, 700032, India.
authors.forename: Writachit
authors.initials: W
authors.lastname: Chakraborty
authors.affiliation: Division of Bacteriology, National Institute of Cholera and Enteric Diseases (NICED), P-33 CIT Road, Scheme XM, Beliaghata, Kolkata, 700010, India.
authors.forename: Hemanta
authors.initials: H
authors.lastname: Koley
authors.affiliation: Department of Life Science & Biotechnology, Jadavpur University, 188 Raja S.C. Mullick Road, Kolkata, 700032, India. ratangachhui@yahoo.com.
authors.forename: Ratan
authors.initials: R
authors.lastname: Gachhui
mesh_terms: D000900:Anti-Bacterial Agents / Q000737:chemistry / Q000494:pharmacology*; D004755:Enterobacteriaceae / Q000187:drug effects*; D004756:Enterobacteriaceae Infections / Q000382:microbiology*; D006801:Humans; D013058:Mass Spectrometry; D008826:Microbial Sensitivity Tests; D010936:Plant Extracts / Q000737:chemistry / Q000494:pharmacology*; D059808:Polyphenols / Q000737:chemistry / Q000494:pharmacology*; D013662:Tea / Q000737:chemistry*
chemical_list: D000900:Anti-Bacterial Agents; D010936:Plant Extracts; D059808:Polyphenols; D013662:Tea