CAJ | 학술논문

应用大剂量重离子束12C6+对菌株H3001进行二次辐照选育，对初选获得的高产柠檬酸菌株进行摇瓶发酵试验及10～100 L中试发酵罐试验，采用酸碱中和法测定发酵液中柠檬酸的含量。结果表明：当二次重离子12C6+剂量为857.8 Gy时，致死率和正突变率达到最大值，分别为94.5%和8%。通过摇瓶发酵试验，最终获得一株高产柠檬酸菌株hw317，控制该菌株发酵周期为60 h，柠檬酸酸度能达到19.2±0.2%。
응용대제량중리자속12C6+대균주H3001진행이차복조선육，대초선획득적고산저몽산균주진행요병발효시험급10～100 L중시발효관시험，채용산감중화법측정발효액중저몽산적함량。결과표명：당이차중리자12C6+제량위857.8 Gy시，치사솔화정돌변솔체도최대치，분별위94.5%화8%。통과요병발효시험，최종획득일주고산저몽산균주hw317，공제해균주발효주기위60 h，저몽산산도능체도19.2±0.2%。
Heavy 12C6+ ion beams in various high doses were employed to irradiate H3001 strain for screening As-pergillus niger strain for hyper citric acid production. Three high-yield strains were obtained after shaker fermentation test. Among the three strains, the strain hw317 was implemented shaker fermentation for stability test and 10～100 L pilot fermentation tank for citric acid productive maximization. Acid-base neutralization method was applied to determi-nate the content of citric acid in fermented liquid. The results showed that: when the secondary heavy ion 12C6+ dose was 857.8 Gy, both of the fatality rate (94.5%) and the positive mutation rate (8%) were highest. Through the shaker fermentation tests and 10～100 L pilot fermentation test, one strain hw317 was screened and obtained for hyper citric acid production. Consequently, the final citric acid acidity can reach up to 19.2±0.2%with controlling fermentation cycle for 60 h.