Elok Zubaidah, Maryam Tsaqifah Muwahhidah, Hidayat Sujuti, Nur Kusmiyati, Viera Nuriza Pratiwi, Eirene Charista Dea
Kombucha fermentation of soursop leaves is associated with changes in functional properties through post-fermentation physicochemical and metabolite profile modifications. This study was evaluated for its effects on physicochemical properties, qualitative LC-MS metabolite profiles, antioxidant capacity, and in vitro anticancer activity against T47D breast cancer cells. Fermentation was carried out for 12 days using leaf concentrations of 0.6%-2.0%, followed by measurements of pH, total microbial counts, total phenolic and flavonoid contents, antioxidant activity, and LC-MS metabolite profiling. Cytotoxicity and apoptosis induction were assessed using CCK-8 assays, morphological observations, fluorescence imaging (DAPI, Annexin V-FITC/PI), and flow cytometry. At a 1.4% leaf concentration, endpoint comparison between day 0 and day 12 showed an increase in total viable counts from 6.77 to 7.65 log CFU/mL and a marked increase in total phenolic content from 198.13 to 322.03 mg GAE/mL, accompanied by the greatest reduction in antioxidant IC₅₀ values (from 252.29 to 99.73 ppm). Qualitative LC-MS profiling revealed differences in detected compounds between fermented and unfermented samples, including the presence of aglycone flavonoids in fermented kombucha. Acidic soursop kombucha demonstrated the strongest cytotoxicity toward T47D cells (IC₅₀ = 2.35 mg/mL), followed by neutralized kombucha (IC₅₀ = 3.87 mg/mL) and soursop leaf drink (IC₅₀ = 7.37 mg/mL). Flow cytometry indicated a marked shift toward apoptotic populations in fermented samples, with combined early and late apoptosis reaching 83.56% in acidic kombucha treated cells. Kombucha fermentation under acidic conditions was associated with enhanced antioxidant capacity and in vitro anticancer related activity of soursop leaves. © 2026, Walailak University. All rights reserved.
Department of Food Science and Biotechnology, Faculty of Agricultural Technology, Universitas Brawijaya, East Java, 65145, Indonesia; Department of Biomedical, Faculty of Medicine, Universitas Brawijaya, East Java, 65145, Indonesia; Department of Nutrition, Faculty of Health, Universitas Nahdlatul Ulama Surabaya, Surabaya, 60237, Indonesia
