氧化亚铁硫杆菌的分离鉴定及培养条件优化

Isolation and identification of Thiobacillus ferrooxidans and optimization of its culture condition

摘要:

【目的】获得可用于浸矿的菌株, 对其培养条件进行优化。【方法】从成都热电厂采集土样中分离得到一株菌株, 分析该菌株的形态学特征、培养特征及16S rDNA序列, 确定菌株的分类地位。利用Design-Expert软件中的Box-Behnken法设计实验, 通过响应面分析对初始pH值、温度、接种量和装液量4个因素进行优化, 确定其最适培养条件。【结果】获得菌株Z1, 该菌为革兰氏阴性菌, 短杆状, 经16S rDNA 鉴定为嗜酸性氧化亚铁硫杆菌(Acidithiobacillus ferrooxidans, 简称At. f)。确定菌株最适培养条件为: pH 1.8、温度30 °C、接种量14%、装液量250 mL摇瓶装60 mL培养液。在此条件下, Z1的亚铁氧化率可达99.7%。【结论】Z1菌株适合于生物浸矿的应用。

Abstract:

[Objective] A strain with the ability of bioleaching was isolated. Its culture condition was optimized. [Methods] The strain was isolated from the soil collected from thermoelectric plant in Chengdu, whose taxonomic status was identified based on analysis of morphology characteristics, culture characteristics and 16S rDNA sequence. The optimization experiment was designed with Box-Behnken method in the software Design-Expert, in which the four factors of culture condition that initial pH, temperature, inoculum amount and liquid volume were investigated. Then the results were analyzed with the response surface analysis (RSA) and the optimal culture condition was determined. [Results] The isolated strain was Gram-negative and short-rod, which was named as Z1 and identified as Acidithiobacillus ferrooxidans strain by analysis of its 16S rDNA sequence. The optimal culture condition of the strain was determined, which was initial pH 1.8, optimum temperature 30 °C, inoculum volume 14% and liquid volume 60 mL medium in a 250 mL flask. Under the optimum condition, the oxidation rate of ferrousion reached at 99.7%. [Conclusion] The strain Z1 was appreciated for bioleaching.