毒死蜱高效降解酶保护剂配方优化及稳定性

Optimization of Enzyme Protectant of Chlorpyifos-Biodegradation Fungi and Its Stability

【目的】优化毒死蜱高效降解酶液保护剂组成配方,明确其在不同条件下降解毒死蜱的稳定性。【方法】在自主筛选毒死蜱高效降解真菌Cladosporium cladosporioides(菌种保藏号CCTCCM207111,ITS序列分析GeneBank登陆号EF405864)的基础上,发酵提取其胞外酶,采用"通用旋转回归法"筛选了酶活性保护剂的最佳配方,并进行验证;利用所得配方进行制剂贮藏实验,利用HPLC检验其降解性能稳定性。【结果】所得酶活性保护剂最佳配方为0.70%氯化钠,0.35%甘氨酸,0.03%苯甲酸钠,0.17%凯松,8.38%甘油,所配制降解酶保护剂在贮藏温度20～50℃,贮藏5个月以内,反应体系中制剂酶蛋白终浓度为9.90mg·L-1降解处理10min时对50mg·L-1毒死蜱降解效果保持在80%以上,光照对降解效果没有显著影响。【结论】所得毒死蜱高效降解酶保护剂配方经济、稳定,为今后商品化生产降解酶制剂,处理农产品农药残留提供了基础。

[Objective] The objective of this study was to optimize the composition of enzyme protectant of chlorpyifos-biodegradation fungi and determine its stability. [Method] Based on the screening of chlorpyrifos biodegrading fungal strain, Cladosporium cladosporioides （the ID of fungi preservation CCTCCM207111. Accession number of ITS sequence analysis Genebank EF405864）, extraceltular enzymes were extracted. Applying the composite rotatable design, a model of the optimal mixture protect agents was established. After the optimal composition was validated, the enzyme preparation storage experiment was tested to determine the stability of biodegradation by high performance liquid chromatography analysis. [Result] The results showed that the optimal composition was 0.70% NaCl, 0.35% glycine, 0.03% sodium benzoate, 0.17% Cosmetic, and 8.38% glycerol When 9.90 mg·L^-1 of final concentration of emzyme protein was added into the 50 mg·L^-1 of chlorpyrifos, results of HPLC analysis after biodegradation 10 min indicated that the degradation rate of the enzyme preparations was more than 80% after storage 5 months under the temperature from 20℃ to 50℃ and the light almost has no effect on the degradation rate. [Conclusion] It is concluded that an economical and stable enzymic protectant of chlorpyifos-biodegradation fungi is got, which has provided a foundation for commercial production of enzymic preparation in dealing with pesticide residues of agricultural products.