2株西玛津降解菌的降解特性研究

Degradation Characteristics of Two Simazine-degrading Bacterial Strains

利用2株降解细菌S-1和S-3对西玛津进行生物降解,研究其降解能力及降解特性。通过紫外可见分光光度法测定OD600考察S-1和S-3的生物学特性,高效液相色谱法检测不同条件下两菌对西玛津降解效果的影响以及混合菌的降解效果。结果表明:在30℃,pH 7.5条件下培养72 h后,0.2 mg·L^(-1)西玛津降解率均可达到99%以上;两菌对中低浓度底物(0.2~10.0 mg·L^(-1))的降解效果较好,72 h几乎降解完全,高浓度(25.0~50.0 mg·L^(-1))则不利于降解,50.0 mg·L^(-1)时S-1和S-3最高降解率分别为56.67%和75.53%,外加少量碳源和氮源后降解速率均有所提高;混合菌的最佳配比为1∶1,此时西玛津降解率最高,混菌的降解速率及降解能力均强于单菌,可见S-1和S-3对西玛津均具有较强的降解能力,说明两株降解菌在残留西玛津污染治理中具有独特的应用前景。

Two degradation bacterial strains S-1 and S-3 were used to biodegrade simazine to study their degradation capability and characteristics. The optical density OD600 was determined by Vis-UV Spectrophotometry to study biological characteristics of S-1and S-3,the effects of different conditions on the simazine degradation was researched by HPLC and the degradation efficiency of mixed bacterias for simazine. The results showed that the degradation rate of 0.2 mg·L^（-1） simazine reached 99% within 72 h under the condition of 30 ℃,pH 7.5;The lower-middle concentrations（0.2-10.0 mg·L^（-1）） were degraded completely and high concentrations（25.0-50.0 mg·L^（-1））were not conducive to degrade within 72 h by S-1 and S-3,the maximum degradation rate of S-1 and S-3 were56.67% and 75.53% respectively,when the concentration was 50.0 mg·L^（-1）.The degradation efficiency was improved by adding a small amount of carbon source and nitrogen source.The degradation rate of simazine reached the highest when the ratio was 1 ∶1,the degradation rate and ability was better than single bacterium. S-1 and S-3 had stronger degradation capacity,which illustrated they had special application potential in dealing with the pollution caused by simazine.