摘要: | 茶 (Camellia sinensis) 的消耗量僅次於水,是被廣泛接受與消耗的飲品。茶葉製品與茶飲對人體的各種生理保健功效已被證實,如增強免疫力、止渴及降低膽固醇等。茶葉中各活性物質以多酚類化合物最為突出,不僅含量高、部分物質為茶葉特有並且其具有顯著的抗氧化活性。近期因保健與健康飲食的意識增長,人們開始尋求具有療效或功能性的茶飲。而由微生物發酵製成的後發酵茶,因其獨特的代謝物質與顯著的生物活性愈受重視。依特定菌株以及不同發酵條件,可製備出各式具特殊生物活性的後發酵茶。乳酸菌投入食品發酵工程歷史悠久,其具有顯著的功能性及作為益生菌的潛力,更擁有代謝生產GABA及多酚類物質的能力。本研究目的在於利用布氏乳桿菌 (Lactobacillus buchneri BCE119151) 發酵茶葉,並透過最適化發酵條件及各項發酵參數探討,以達到最適化生產GABA以及提升其抗氧化活性。 本研究將探討各發酵條件—茶葉粉末添加量、不同碳源及添加量、不同氮源及添加量、起始pH值、MSG濃度以及發酵溫度,並依菌種生長活性、生產GABA活性以及抗氧化活性等參數進行最適化討論。本研究成功以最適化發酵條件—添加4%茶葉粉末、3%蔗糖、4% MRSN medium、起始pH值6.0及發酵溫度37℃在發酵後達到GABA產量21.784 g/L、單位MSG對GABA轉化率YG/M 0.538 g/g、最大菌落數VCCmax 9.391 log CFU/mL、單位菌重對GABA轉化率YG/VCC 2.320 g/g、總多酚含量0.589 g GA/L、以及DPPH自由基清除能力40.14%。綜合上述結果,L. buchneri BCE119151菌種結合茶葉進行發酵,可發展出具有高生物活性的茶葉發酵成品,並將其應用於相關飲品以及保健食品的開發。 ;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. |