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从不同生境(食品、土壤、空气、有机质等)收集到的自然发酵样品中分离得到150株曲霉属菌株.用高效液相色谱(HPLC)法检测发酵液中洛伐他汀(Lovastatin)含量,筛选获得1株稳定高产Lovastatin的曲霉菌株(编号:Ac-32).根据菌落形态特征并结合18 S rDNA测序,鉴定其为棒曲霉(Aspergillus clavatus).通过摇瓶发酵单因素实验优化了碳氮源种类、碳氮源含量、碳氮比(C/N)、发酵温度、初始pH、转速、种龄和接种量,确定了棒曲霉菌株Ac-32摇瓶发酵产Lovastatin的适宜条件为:乳糖为碳源、蛋白胨为氮源、碳源含量为100 g/L、氮源含量为12 g/L、碳氮比(C/N)为15:1.8、温度28℃、转速180 r/min、初始pH 5.2、种龄4 d、接种量6%.采用Minitab 17软件的P-B实验设计法,筛选对Lovastatin产量有显著影响的因素为:温度、pH、碳源含量和氮源含量.根据P-B实验结果,运用响应面法分析,确定棒曲霉菌株Ac-32产Lovastatin的最优条件为:碳源含量100 g/L,氮源含量11.8 g/L,温度28℃,pH 5.2.在此条件下,Lovastatin最高产量为236.221μg/mL.“,”150 Aspergillus strains were selected from different natural fermentation samples of food, soil, air and so on, and their products of lovastatin were measured by high performance liquid chromatography ( HPLC ) method. Among them, the Aspergillus strain Ac-32 producing higher-level lovastatin was screened. Based on 18S rDNA sequence and morphology characteristics, the strain Ac-32 was identified as Aspergillus clavatus. Through analyzing the influence of C source, N source, C content, N content, C/N, temperature, initial pH and so on, the results indicated that optimal fermentation conditions were as follows:C source lactose, N source peptone, C content 100 g/L, N content 12 g/L, C/N 15:1. 8, temperature 28 ℃, shaking speed 180 r/min, initial pH 5. 2, inoculating age 4 d and inoculum size 6%. Using Plackett-Burman ( P-B) in Minitab 17, 4 significant effects ( C content, N content, temperature and pH) on lovastatin yields were screened out. According to the P-B experiment results and analysis of response surface methodology in Design Expert, the optimum conditions were as follows:C content 100 g/L, N content 11. 8 g/L, temperature 28 ℃, pH 5. 2. Under the optimized conditions, the maximum lovastatin yield was 236. 221 μg/mL.