关键词: 德国小蠊, 羧酸酯酶, 正交试验, 方差分析, 最佳条件

Abstract: Objective To confirm the resistance status of Blattella germanica through studying its carboxylesterases(CarE) characteristics systemically and establish a quick, accurate and simple detection method. Methods The optimal concentrations of CarE and substrate, pH, temperature and reaction time of the reaction system, were determined by orthogonal matrix methods. And the optimal group was selected in the experiment. The data was analyzed with range analysis and analysis of variance. Results The results revealed that there were significant difference among various levels of the selected five factors which affected specific activity of CarE from Blattella germanica. The optimal levels of A (CarE concentration), B (substrate concentration), C (reation time), D (reation temperature) and E (pH of reation system) were A₄ (0.35 head/ml), B₃ (0.6 mmol/L), C₁ (5 minutes), D₄ (40 ℃) and E₂ (pH 6.5), respectively. The results of range analysis and variance analysis indicated that the optimal combination was A₄B₃C₁D₄E₂, and the maximum specific activity of CarE was 37.286 μmol/(mg pro·min) determined under the optimal conditions. The effect of factors on CarE specific activity were in the order of temperature>time>substrate>enzyme concentration>pH. Conclusion The optimal condition were: 0.35 head/ml, 0.6 mmol/L substrate, 5 mintues, 40 ℃, respectively.