- 學位論文
以狼尾草和米糠為固態發酵基質生產纖維水解酶之研究
Rice Bran and Napiergrass as the Substrate for Cellulase Production under Solid-State Fermentation
摘要
本研究以狼尾草和米糠為基質，木黴菌Trichoderma reesei RUT-C30為生產菌株，利用錐形瓶進行小規模固態醱酵，探討培養條件對纖維素水解酶 (cellulase)生產的影響，所探討的條件涵蓋狼尾草之預處理方式、狼尾草和米糠的比例、醱酵時間、溫度、起始濕度與酸鹼度。研究結果顯示，最佳培養溫度、起始濕度與醱酵時間分別為30°C、70%與6天，最適起始pH值為3-6，最佳狼尾草對米糠的質量比例為2 : 3，而狼尾草的蒸爆預處理對纖維素水解酶的生產沒有幫助，使用蒸爆預處理過之狼尾草反而造成酵素活性下降。以未經預處理的狼尾草與米糠進行固態醱酵，於最適條件下培養，纖維素水解酶活性可達26.8 ± 1.6 FPU/g dry substrate，β-葡萄糖苷酶活性可達20.0 ± 1.1 IU/g dry substrate。
並列摘要
Napiergrass and rice bran were used as the substrate for the production of cellulolytic enzymes by Trichoderma reesei RUT-C30 under solid-state fermentation (SSF). The effects of several fermentation conditions, including substrate pretreatment and ratio, temperature, initial moisture content and pH, and culture time, on resulting filter paper activity were investigated. The results indicate that the optimal temperature, initial moisture content, and culture time were 30°C, 70% and 6 days, respectively. The highest filter paper activity was obtained at a napiergrass to rice bran mass ratio of 3:2, and the initial pH in the range of 3-6. Surprisingly, steam-explosion pretreatment of napiergrass did not improve cellulase production; lower filter paper activity resulted when pretreated napiergrass was used in the fermentation. The highest cellulase and β-glucosidase activities achieved in this study were respectively 26.8 ± 1.5 FPU/g dry substrate and 20.0 ± 1.1 IU/g dry substrate, which were obtained using untreated napiergrass and rice bran as the substrate under the optimal culture condition.