Comprehensive Evaluation of Three Important Herbs for Kombucha Fermentation

Research background. Kombucha is consumed worldwide for its beneficial health ef-fects. Kombucha teas fermented with various herbal infusions have become very impor-tant nowadays. Although black tea is used for kombucha fermentation, kombucha teas fermented with different herbal infusions have gained great importance. In this study, three different traditional medicinal plants, namely hop (Humulus lupulus L.), madimak (Polygonum cognatum) and hawthorn (Crataegus monogyna) were used for the fermenta-tion of kombucha beverages, and the bioactivity of these beverages was investigated ex-tensively. Experimental approach. The microbiological profile, bacterial cellulose formation, an-tibacterial, antiproliferative and antioxidant activities, sensory properties, total phenolic content and flavonoid content of kombucha beverages were investigated. Liquid chro-matography-coupled mass spectrometry analysis was used to identify and quantify spe-cific polyphenolic compounds in the samples. Results and conclusions. According to the results, the hawthorn-flavoured kombucha, which has lower free radical scavenging activity than the other samples, came into prom-inence in terms of sensory properties. All examined kombucha beverages showed a strong cytotoxic effect on Mahlavu and HCT116 cell lines, but only the madimak-flavoured kom-bucha sample, which had a higher total phenolic/flavonoid content, had antibacterial ac-tivity against all microorganisms used in the study. Novelty and scientific contribution. Considering the results of this study, madimak could be an effective herb for the development of new kombucha beverages, although its sen-sory properties still need to be improved. This study contributes to science in terms of producing new fermented beverages with improved beneficial health effects.