中药菊花过氧化物酶酶学特性及炮制工艺的研究

Study on Characters of Peroxidase in Chinese Medicine Chrysanthemum and its Processing Technology

目的探讨中药菊花过氧化物酶酶学特性及炮制工艺。方法以愈创木酚为底物,采用分光光度法测定菊花过氧化物酶的酶学特性,并比较不同加工工艺下菊花过氧化物酶学特性及总黄酮含量。结果菊花反应时间不宜超过2 min,最适pH 7.0,最适温度36℃,100℃处理30 s后,过氧化物酶活性完全丧失。过氧化物酶催化的酶促褐变反应动力学符合米氏方程,动力学参数Km=1.58×10^(-2) mol/L,Vmax=14.278 U/min。四种炮制工艺比较过氧化物酶的抑制效果为水蒸汽>微波干燥>80℃热风干燥>自然阴干。分光光度计法测定样品总黄酮含量,蒸制干燥>微波干燥>80℃热风干燥>自然阴干。结论菊花过氧化物酶适应温度范围广,20~80℃,相对耐热性好。本研究可为中药菊花炮制工艺的改善提供理论参考。

Objective To observe the peroxidase（POD） character and processing technology of chrysanthemum. Methods The enzymatic characteristics of POD from chrysanthemum were investigated by spectrophotometry, with the guaiacol as substrate. The POD and total flavonoid content under different processing technology were compared. Results The reaction time for POD should not exceed 2 min, the optimum pH and temperature of POD were 7.0 and 36 ℃, respectively. The POD activity was completely inactivated when it was incubated at 100 ℃ for 30 s. The reaction kinetic of enzymatic browning was accordant withkinetic parameters. The Km and Vmax were 1.58 ×10^（-2）mol/L, 14.278 U/min, respectively. Four processing methods show different effects on POD activity, and their inhibitory capacity was steaming drying microwave drying 80 ℃ hot air dryingnatural shade drying. Conclusion The POD in chrysanthemum has a wide range of adapting temperature, 20~80 ℃,and good relative thermal stability. This research can provide reference for the processing technology of chrysanthemum.