醱酵培養對於基因重組E. col i生產endo-glucanase之研究

This study used recombinant E. coli BL 21cultured in jar fermentor to produce endo-glucanase. In this experiment, medium composition，inducer and feeding components were tested their effect on the production of endo-glucanase. By using Luria Bertani (LB) broth after 12 hours of fermentation the dried cell weight reached 3.56 g/L; in using IPTG as inducer in the 12 hrs fermentation broth, the induced enzyme activity was 570 U / L and protein concentration is 1888 mg/L after 48 hrs induction in the flask culture. Meanwhile when the induction was performed in the whole broth within fermentor for 48 hrs，the induced enzyme activity was 567 U/L and protein concentration was 1967 mg/L. Therefore, there are similar result of induced enzymatic activity during two types of induction. By using Terrific Broth (TB) broth after 12 hours of fermentation, the dried cell weight could reach 8.84 g/L. In using IPTG as inducer in the 4 hrs fermentation broth with induction for 48 hrs, the induced enzyme activity was 944 U/L and protein concentration was 1099 mg/L，but in 12 hr fermentation broth with induction for 48 hrs, the induced enzyme activity decreased to 624 U/L。When using Disaccharide as inducer in the 4 hrs fermentation broth with induction for 48 hrs, the induced enzyme activity reached 1075 U/L and protein was 1814 mg/L，then in the 12 hr fermentation broth with induction for 48 hrs, the induced enzyme activity decreased to 694 U/L. Therefore, there was similar result of induced enzymatic activity by using IPTG or Disaccharide as the inducer. By using alcohols as the feeding carbon source，by setting controlled alcohols concentration in the rage of 3 g/L and using Disaccharide as inducer, in the 6 hrs fermentation broth with induction for 48 hrs, the induced enzyme activity was 888 U/L and protein concentration was 1447 mg/L, but in the 12 hrs fermentation broth with induction for 48 hrs, the induced enzyme activity reached 1073 U/L and protein concentration is 2003 mg/L. By controlling concentration of alcohols in the range of 4 g/L，in the 6 hrs fermentation broth and induction for 48 hrs, the induced enzyme activity was 1380 U/L and protein concentration is 1992 mg/L，but in the 12 hrs fermentation broth with induction for 48 hrs, the induced enzyme activity decreased slightly to 1276 U/L and protein concentration was 2571 mg/L. By using a fixed flow rate of feed (50 g/L alcohols) and pumping flow rate of 1.33 g/min，in the 12 hrs fermentation broth with induction for 48 hrs, the induced enzyme activity was 1296 U/L and protein concentration was 2362 mg/L. Enhancing the concentration of stocked alcohols concentration to 75 g/L and pumping flow rate of 1.37 g/min，in the 10 hrs fermentation broth with induction for 48 hrs, the induced enzyme activity was 1588 U/L, and protein concentration was 2140 mg/L. Therefore the fixed flow rate of alcohols in the feeding stream can help for the development of automatic production process.