不同诱变方法选育嗜酸乳杆菌NX2-6类细菌素高产菌株

Different mutation methods of Lactobacillus acidophilus NX2-6 for improving antifungal activity

摘要: 采用60Coγ射线、硫酸二乙酯（DES）、原生质体紫外3种诱变方法对嗜酸乳杆菌（Lactobacillus acidophilus）NX2-6进行诱变,以期获取高产类细菌素菌株。结果表明,60Coγ射线诱变的最佳辐照剂量为2.0k Gy,DES处理的最佳条件是浓度为0.7%的DES处理菌体10min,原生质体紫外诱变最佳照射时间为20s,分别得到高产菌γ56,D47和UV156,它们的抑菌效价分别为6096.78,5384.98U/m L和6230.79U/m L,是出发菌株抑菌效价（2819.36U/m L）的2.16、1.91、2.21倍。传代表明,突变株γ56、D47、UV156具有稳定的遗传性。

Abstract: Lactobacillus acidophilus NX2- 6 was mutated by60 Co γ irradiation,DES and UV of protoplasts respectively,aiming to obtain high productivity of bacteriocins stains.The results showed that the optimal condition of60 Co γ irradiation was 2.0k Gy,the best mutant condition of DES was the concentration of 0.7% to treat bacteria for 10 min,and the UV of protoplasts best irradiation time was 20 s.Then high productivity strains γ56,D47 and UV125were screened respectively. Moreover,their antibacterial titers were 6096.78,5384.98 U / m L and 6230.79 U / m L. The antibacterial titers of γ56,D47,UV156 was 2.16,1.91,2.21 times than the initial strain( 2819.36 U / m L) respectively. The bacteria passage test indicates that mutant strains γ56,D47,UV156 have the stable heredity.