氧化亚铁硫杆菌的分离及其培养条件优化

目的:获得可应用于烟气脱硫的菌株,并对其培养条件进行优化.方法:从化工厂取土样分离氧化亚铁硫杆菌,分析分离菌株的形态学特征、培养特征及16S rDNA序列,确定菌株的分类地位.通过单因子实验,对培养基中主要成分硫酸亚铁和硫酸铵的浓度进行优化.利用SAS软件中的Box-Behnken法设计实验,通过响应面分析对初始pH、温度、接种量、装液量4个因素进行优化.结果:获得菌株N16,经鉴定为嗜酸性氧化亚铁硫杆菌(Acidithiobacillus ferrooxidans).确定FeSO_4·7H_2O和(NH_4)_2SO_4的最适添加量分别为60/L和1g/L.确定菌株最适培养条件为:初始pH 1.8,温度28℃,转速150r/min,接种量15%,装液量30mL.在最适培养墓及培养条件下,菌株N16的亚铁氧化率可达99.78%.结论:分离得到的菌株适合于微生物法烟气脱硫的应用.

Isolation of Acidithiobacillus ferrooxidans and Optimization of Its Culture Condition

Objective: A strain with the ability of flue gas desulfurization was isolated.Its culture condition was optimized.Method: Acidithiobacillus ferrooxidans (A.f) was isolated from the soil collected from chemical plant.Based on its morphologic and cultural characteristics and the sequence of 16S rDNA, the taxonomic position of the strain was determined.Through single -factor experiment design, the concentration of FeSO_4·7H_2O and (NH_4)_2SO_4 was optimized.By the software SAS, the culture condition was optimized designed with Box- Behnken way.And the results were analyzed with the response surface analysis(RSA).Result: The isolated strain was named as NI6 and identified as Acidithiobaeillus ferrooxidans.The optimum concentration of FeSO_4·7H_2O and (NH_4)_2SO_4 was 60g/L and 1g/L respectively.The optimum culture condition was : pH 1.8, optimum temperature 28℃, inoeulum volume 15％, a 250 mL flask containing 3OraL medium.Under the optimum condition, the oxidation rate of ferrous ion reached at 99.78％.Conclusion: The strain was appreciated for the flue gas desulfurization.