γ-聚谷氨酸是一种由生物所合成的氨基酸聚合物,具有极强的水溶性,生物相容性,能被广泛的运用到食品、医药、日化、环保、农业等行诸多领域,具有巨大的市场前景.本实验以实验室保藏的一株产γ-聚谷氨酸(γ-PGA)地衣芽孢杆菌Bacillus licheniformis QY-27为出发菌株,通过常压室温等离子体(ARTP)诱变,筛选获得一株遗传性能稳定的高产γ-聚谷氨酸突变菌株Bacillus licheniformis QS-21,该突变菌株γ-聚谷氨酸的产量较出发菌株的9.12g/L,提高了42.26％,达到15.89g/L.对筛选获得的变异株发酵条件优化结果显示,L-谷氨酸20g/L,甘油100g/L,MgSO4·7H2O 0.5g/L为变异株合适发酵培养基,在37℃,摇瓶转数230r/min,发酵培养72h,γ-聚谷氨酸的产量达22.56g/L,比优化前提高了29.56％.%As a high molecular amino acid from biosynthesis, γ-PGA has high water solubility and biocompatibil-ity, which can be widely used in food, medicine, household chemicals, environmental protection, agriculture and other fields, and thus has great market prospect. Bacillus licheniformis QY-27 preserved in the laboratory was used as original strain capable of producing γ-PGA, which was treated ARTP in order to obtain the high-yielding strain of γ-PGA, After the mutagenesis, one mutant named Bacillus licheniformis QS-21 formed, The yield of γ-PGA increased by 42.26％from 9.12g/L to 15.89g/L and showed high hereditary stability. through Optimized fer-mentation conditions, the results showed that the optimal fermentation medium was l-glutamic acid 20g/L, glycerol 100g/L,MgSO4·7H2O 0.5g/L, and the optimal fermentation condition was 37℃, 230r/min, cultivated for 72 hours Compared with before the optimization, the yield of γ-PGA increased by 29.56％ to 22.56g/L.
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