Honey utilization in soursop leaves (Annona muricata) kombucha: Physicochemical, cytotoxicity, and antimicrobial activity

Abstract

Kombucha is a prominent fermentation beverage for its antioxidant, antimicrobial, and therapeutic properties. In this study, we utilized soursop leaves infusion with different concentrations (0.5%, 1%, and 1.5% (w/v)) and honey as the carbon source to determine the physicochemical, antimicrobial, and cytotoxicity properties in the kombucha consortium after 15 days of fermentation. The soursop leaves kombucha (1.5% (w/v)) performed the highest antioxidant capacity and positive antimicrobial activity against two pathogenic bacteria, Escherichia coli, and Staphylococcus aureus. A lower acid and alcohol content in the soursop leaves kombucha beverage could be considered safe for Halal consumption in line with the cytotoxicity evaluation against HaCaT keratinocyte cells that have more than 80% viability and are considered non-toxic. Antioxidant capacities through DPPH (2,2-diphenyl-1-picrylhydrazyl) radical scavenging assay and vitamin C analysis revealed that soursop leaves kombucha enriched with honey are a potent antioxidant beverage. A gas chromatography-mass spectroscopy (GC-MS) analysis revealed that most organic acids in the soursop leave kombucha were ethanoic, propanoic, butanoic acids, and some volatile compounds considered to have antimicrobial properties.