亚硝基胍诱变丙酸杆菌选育高产抑菌物质菌株

目的]提高丙酸杆菌代谢物的抑菌活性,为薛氏丙酸杆菌代谢物的工业化生产奠定基础。方法]以实验室保藏的薛氏丙酸杆菌H1310为出发菌株,采用亚硝基胍(NTG)进行诱变处理,待突变菌株长出后采用双层平板筛选法进行筛选,而后通过深层液体发酵对筛选到的菌株进行复筛。结果]当最优的NTG诱变浓度为0.3 mg/m L时,致死率为90.69%。采用双层平板法,从3 564株菌落中挑选出87株突变株,进一步进行复筛,获得一株突变菌株,其代谢物抑菌活性达(28.30±2.47)AU/m L,比出发菌株提高43.87%。结论]确定了丙酸杆菌NTG诱变选育的试验方法,获得一株抑菌活性高的遗传性能稳定的菌株。

Screening of Propionibacterium shermanii Strains with High Production Antibacterial Metabolites by NTG Mutation

Objective] To improve the antibacterial activity of the metabolite of Propionibacterium shermanii and lay a foundation for the industrial production of the metabolite.Method] This research used Propionibacterium shermanii H1310 as the original strain,through nitrosoguanidine (NTG) mutagenesis,using the double-layer plate screening method to screen the mutant strains.The strains which were surrounded by clear inhibition zone were cultivated and measured the antibacterial activity.Result] The optimal concentration of NTG was 0.3 mg/mL,for the lethality rate was 90.69％.87 strains chosen from 3 564 strains were fermented again.A high antibacterial metabolites stain NTGll0605 was selected and its antibacterial activity reached (28.30 ± 2.47) AU/ mL,which was 43.87％ higher than the original strain.Conclusion] The experimental methods of mutation breeding of Propionibacterium shermanii is confirmed and a strain which produced more antibacterial substances is obtained.