费氏丙酸菌维生素B1营养缺陷型菌株的诱变选育

摘要

在丙酸发酵过程中，乙酸为主要副产物，维生素B1与乙酸合成途径相关，筛选维生素B1营养缺陷型突变株有助于降低乙酸的合成，提高丙酸的产量。以费氏丙酸菌IFFI．10019作为出发菌株，经过紫外线诱变处理，筛选育种获得维生素B1营养缺陷型费氏丙酸菌二株，其中Pf007菌株的丙酸产量由原来的1．1 g/L提高到2．1 g/L，提高率达到91％。%Acetic acid is one of main by-products in propionic acid fermentation. Vitamin B1 is involved in acetic acid biosynthesis. The vitamin B1 auxotrophy would reduce the acetic acid biosynthesis, which result in increase of propionic acid yield. A vitamin B1 auxotrophy mutant Pf007 was screened out from Propionibacteria freudenreichii IFFI.10019 by UV treatment, and the propionic acid production level reached up to 2.1 g/L,which increased 91% compared with original strain�s 1.1 g/L.