链霉菌HP-S-01降解高效氯氰菊酯的特性及其动力学

Degradation characteristics and kinetics of beta-cypermethrin by Streptomyces sp. HP-S-01

摘要:

研究不同接菌量、温度、pH、装液量和农药初始浓度对链霉菌HP-S-01降解高效氯氰菊酯的影响。结果表明, 在接菌量为0.6 g/L、28 °C、pH 7.5和装液量为50 mL/250 mL三角瓶条件下培养3 d, 该链霉菌对100 mg/L高效氯氰菊酯降解率达到96%以上。链霉菌HP-S-01还能明显降解高效氟氯氰菊酯、高效氯氟氰菊酯、右旋苯醚菊酯和胺菊酯等拟除虫菊酯农药, 且降解过程符合一级动力学模型, 降解半衰期分别为0.78、0.88、1.08和1.24 d。采用Andrews方程对链霉菌HP-S-01降解高效氯氰菊酯的过程进行拟合, 其动力学参数为qmax=1.826 3 d?1, Ks=58.951 3 mg/L, Ki=359.378 2 mg/L, 该链霉菌降解高效氯氰菊酯最佳的初始浓度为145.553 5 mg/L, 试验数据与该动力学方程拟合较好。

Abstract:

The beta-cypermethrin degradation conditions including inoculum amount, temperature, pH, liquid volume, and initial concentration by Streptomyces HP-S-01 were systematically investigated. The results showed that Streptomyces HP-S-01 degraded beta-cypermethrin rapidly with a degradation rate up to 96% within 3 d, under the conditions of inoculum amount 0.6 g/L, 28 °C, pH 7.5, and liquid volume 50 mL/250 mL. The strain also could effectively degrade beta-cyfluthrin, beta-cyhalothrin, d-phenothrin and tetramethrin. Furthermore, the degradation reaction followed first-order kinetics and half lives (T1/2) were 0.78, 0.88, 1.08 and 1.24 d, respectively. The Andrews model was used to describe the beta-cypermethrin degradation process. The degradation kinetic data collected fitted the model well. The calculated parameters of qmax, Ks and Ki for the model were 1.826 3 d?1, 58.951 3 mg/L and 359.378 2 mg/L, respectively. And the optimal concentration of initial beta-cypermethrin was 145.553 5 mg/L.