发酵法生产京尼平菌株的筛选与培养

从土壤中筛选到一株产β-葡萄糖苷酶的菌株FYS-9，其发酵可将京尼平苷转化为京尼平。通过菌落形态特征、孢子和菌丝显微观察及18S rDNA基因序列分析，初步鉴定该菌株为泡盛曲霉（Aspergillus awamori）。以FYS-9为出发菌株，通过紫外线、原生质体诱变，选育得到一株高产β-葡萄糖苷酶的突变株70C-3，该突变株发酵产酶平均酶活力达到36.15IU/mL，比FYS-9提高39.4%。对突变株70C-3发酵转化京尼平苷条件的优化结果表明，在京尼平苷添加量1.5%，30℃、150r/min转化24h的条件下，京尼平苷的转化率达到97.7%，京尼平的产量可达8.5g/L。

Screening of Aspergillus awamori for the biosynthesis of genipin

A strain of fungus FYS-9 for producing genipin from β-glucosidase was screened from soil.This strain was identified as Aspergillus awamori according to its morphology characteristics and 18S rDNA gene sequence.Strain FYS-9 was utilized as the original strain to obtain another isolated mutant 70C-3.The β-glucosidase activity of strain 70C-3 was 36.15 IU/mL,an improvement of 39.4% compared with the original strain.The optimal conditions were found to be fermentation for 24h with addition of 1.5% geniposide at 30 ℃ with shaking at 150r/min.The conversion of geniposide reached 97.7% and the yield of genipin reached 8.5g/L.