灰葡萄孢霉角质酶粗提液酶学特性研究

为探究灰葡萄孢霉角质酶的酶学性质以及角质酶对植物角质层的降解作用,以灰葡萄孢霉为材料,采用角质诱导的方法得到角质酶发酵液,上清液经过分离得到角质酶粗提液,采用分光光度法探究温度、pH值、金属离子及有机溶剂对角质酶活力的影响,并通过扫描电镜探究角质酶粗提液对葡萄角质层的作用。结果表明,灰葡萄孢霉角质酶的最适反应温度为35℃,最适反应pH值为7.5,此条件下能够保持较高的热稳定性;Na⁺、Mg²⁺、Ca²⁺对酶活有促进作用,而Zn²⁺、Cu²⁺、Fe³⁺对酶活有抑制作用;甲醇、丙酮、异丙醇对酶活具有促进作用,乙醇、乙腈和三氯甲烷对酶活具有抑制作用;角质酶粗酶液对葡萄角质层具有明显的降解作用。本研究结果为果蔬采后病害的控制提供了理论依据。

Enzymatic Properties of Crude Cutinase from Botrytis cinerea

The enzymatic properties of cutinase from Botrytis cinerea and its effect on the plant cuticle were investigated.The cutinase fermentation broth was obtained by cutin induction, and the supernatant was separated to obtain cutinase. The effects of temperature, pH value, metal ions and organic solvent on the activity of cutinase was investigated using spectrophotometry. The effect of crude cutinase on grape’s cuticle was studied by scanning electron microscopy. Results showed that the optimum reaction temperature of cutinase was 35℃, the optimum pH value was 7.5, using high stability can be maintained under this situation. Na⁺, Mg²⁺, Ca²⁺ can promote the activity of cutinase, while Zn²⁺, Cu²⁺and Fe³⁺ inhibited its activity; methanol, acetone and isopropanol promoted the enzyme activity, but ethanol, acetonitrile and chloroform showed the opposite effect; the crude cutinase caused a significant degradation of grapes’ cuticle. This result provides a theoretical basis for the control of postharvest diseases of fruits and vegetables.