Potential of soursop leaves (Annona muricata L.) kombucha beverages on vitamin C content and antimicrobial activity

Kombucha is a traditional beverages product prepared by fermentation of sweet medium and is notable for its health advantages. The present study aimed to evaluate the Vitamin C content and Antimicrobial properties of Soursop Leaves Kombucha during fermentation for 14 days and analyzed with an interval of 7 days. The isolated galactomannan and commercial galactomannan were determined using the Fourier-Transform Infrared Spectroscopy. Furthermore, the vitamin C content was analyzed using U.V Spectrophotometer; meanwhile, the antimicrobial properties of the kombucha beverages were prepared by the agar diffusion method. Different concentrations of soursop leaves were analyzed after 0, 7, and 14 days with three replicates, respectively. The results showed that the content of Vitamin C gradually increased at each concentration and variation time. The vitamin C content reached the highest value of 218.348 ± 1.7769 mg/L with 1.5% (w/v) of soursop leaves and the lowest value of 99.706 ± 1.0707 mg/L with 0.5%(w/v) of soursop leaves. The fermented metabolite showed increasing antimicrobial activity for two weeks of fermentation. It reached the highest value for Staphylococcus aureus at 0.517 ± 0.011 and Escherichia coli at 0.628 ± 0.0281. These data reveal that soursop leaves Kombucha utilized with galactomannan appears to be used as a probiotic drink with high content of Vitamin C.