| dc.description.abstract | Tea (Camellia sinensis) is a widely accepted and consumed beverage, and the consumption of tea is merely second to water. The various physiological health effects of tea on the human body have been confirmed, such as enhancing immunity, quenching thirst, and lowering cholesterol. The most prominent active compounds in tea are polyphenols, which are not only high in content, but also have significant antioxidant activity. Recently, since the increase in awareness of health care and healthy diet, people begin to seek the therapeutic or functional teas. The post-fermentation tea made by microbial fermentation has attracted more attention because of its unique metabolites and significant biological activity. According to specific strains and different fermentation conditions, various post-fermented teas with special biological activities can be prepared. Lactic acid bacteria have significant functionality and potential as probiotics, and have the ability to produce GABA and polyphenols. In conclusion, this study aims to producing GABA by Lactobacillus buchneri BCE119151 fermented with Camellia sinensis and evaluating its antioxidant activity.
In this study, we discussed the fermentation conditions—the amount of tea powder added, different carbon sources and additions, different nitrogen sources and additions, initial pH value, MSG concentration, and fermentation temperature. Optimal conditions were carried out according to the parameters of bacterial growth activity, GABA production and antioxidant activity. Based on the results, the optimal conditions were addition of 4% tea powder, 3% sucrose, 4% MRSN medium, initial pH 6.0, and fermentation temperature 37℃. Under these conditions, BCE119151 showed 21.784 g/L GABA production, YG/M 0.538 g/g, VCCmax 9.391 log CFU/mL, YG/VCC 2.320 g/g, 0.589 g GA/L TPC, and 40.14% DPPH scavenging activity. | en_US |