摘要
通过N+注入处理对γ-氨基丁酸产生菌Lactobacillus brevis TCCC13007进行诱变,离子注入剂量0~2.0×1014cm-2,菌株的存活率呈典型的"马鞍型"剂量-效应曲线,鞍脊出现在8×1012cm-2~4×1013cm-2范围内,菌体存活率在15%~25%,总突变率20%~30%。考虑存活率,总突变率,正突变率等因素,选择离子注入能量30keV,最佳注入剂量4×1013cm-2,获得一支优良菌株Lactobacillus brevis S2,γ-氨基丁酸生产能力提高了31%,经过Design-Expert优化发酵培养基,产量达到35g/L,多次传代培养,遗传性状稳定良好,表明离子注入诱变技术应用于乳酸菌菌种的选育可以获得较为理想的突变株。
Through N^＋ implanting into GABA producing bacteria, the relationship between survival rate of strain and dosage presented a typical ＂sad- dle＂ shaped curve with doses of ion implantation from 0 to 2.0×10^14cm^-2. The ridge of saddle which represented the bacteria survival rate of 15%- 25% in the curve appeared with dose of ion implantation in range of 2.0×10^11cm^-2 to 2.0×10^13cm^-2. The high-yield mutant strain was obtained in 30keV N^＋ with dose of 2.0×10^13cm^-2 and GABA yield of the mutant was increased by 31% than that of original. The GABA yield was improved to 35g/L by optimal fermentation medium which was optimized in Design-Expert system. The work showed that ion implantation is applied well to breeding of lactic acid bacteria strains.
出处
《中国酿造》
CAS
北大核心
2011年第8期117-121,共5页
China Brewing
基金
天津市高等学校科技发展基金计划项目(No.20090601)
关键词
N+离子注入
短乳杆菌
诱变
响应面法
N^＋ implantation
Lactobacillus brevis
mutation
response surface analysis （RSA）
