一株苯系物降解真菌筛选及降解特性

采用逐量分批驯化的方法以污水处理厂污泥作为菌源,苯、甲苯、二甲苯为唯一碳源,驯化、分离、筛选能够有效降解苯系物的真菌,命名为B1。采用单因素以及正交实验方法并对真菌降解环境影响因素及降解效率进行了测定和研究。结果表明:真菌B1对苯系物降解的最佳条件为C:N=5:1,pH5,温度30℃,菌种接种量为5.5ml(50ml培养基)。采用GC对初始液相浓度0~90mg/L范围内的苯系物降解效果进行测定,未发现苯系物对真菌降解活性产生抑制作用。真菌对苯系物的降解效率为:甲苯>苯>二甲苯,最高降解效率分别达到87.39%,85.21%,81.47%。混合物降解效果略高于单一底物的降解效果。

Isolation of a Fungal Strain of Degrading BTEX and Its Degradation Characteristics

By gradually increasing the concentration of BTEX in the culture medium with toluene, benzene and xylene as the sole carbon source, a BTEX-degrading fungi strain which was designated as B1 was isolated from the sludge of sewage treatment plant. Using single factor and orthogonal experiment analyzed and studied the fungal degradation environment effect factors and degradation efficiency. The results showed that the optimum condition of fungal degradation was C:N = 5:1, pH5, temperature 30℃, strains inoculation amount 5.5ml (50ml culture medium). GC analysis was used to determine the fungal degradation effect to BTEX with the initial liquid phase concentration of 0~90mg/L, the results showed that the degradation activities of fungal strain was not inhibited, and the fungal degradation efficiency was toluene > benzene > xylene, the highest degradation efficiency reached 87.39%, 85.21%, 81.47%,respectively. The degradation efficiency of mixed substrates was slightly higher than single substrate.