荔枝中表儿茶素酶促氧化及其抑制的研究  

Inhibition Studies on Enzymatic Oxidation of (-)-Epicatechin in Litchi Pericarp

作　　者：缪文华[1] 刘亮[1] 李小燕[1] 谢笔钧[1] 潘思轶[1] 

机构地区：[1]华中农业大学食品科学技术学院,湖北武汉430070

出　　处：《食品科学》2009年第18期362-366,共5页Food Science

基　　金：国家自然科学基金项目(30270938)

摘　　要：在研究表儿茶素(epicatechin,EC)与荔枝多酚氧化酶(PPO)反应特性的基础上,研究谷胱甘肽(GSH)、L-半胱氨酸(L-Cys)、抗坏血酸(VC)和氟化钠(NaF)对表儿茶素酶促氧化的抑制作用。结果表明,谷胱甘肽和L-半胱氨酸在较低浓度(0.1mmol/L)时就能对此酶促反应产生较好的抑制作用;抗坏血酸在浓度低于0.2mmol/L时能使反应滞后,但对反应速率几乎没有影响;氟化钠在高浓度(大于3mmol/L)下才有一定抑制作用,相对于谷胱甘肽和L-半胱氨酸,其抑制效果较差。同时发现,能对表儿茶素酶促氧化产生抑制的抑制剂,同样能对荔枝多酚提取物(PPE)的酶促氧化产生抑制作用,并且抑制效果相似。To investigate the inhibition effects of some inhibitors such as glutathione, L-cysteine, VC and NaF, （-）-epicatechin was used as the substrate of polyphenol oxidase in this study. Glutathione and L-cysteine showed strong inhibition effects even at low concentration （0.1 mmol/L）. VC could delay the enzymatic oxidation but almost had no inhibition effect on reaction speed at concentrates less than 0.2 mmol/L., NaF displayed only a little inhibition effect at high concentration （3 mmol/L）, which was weaker than those of GSH and L- cysteine. Meanwhile, the study showed that the inhibitors, which could inhibit the enzymatic oxidation of （-）-epicatechin, also could inhibit the enzymatic oxidation of polyphenol extract from litchi pericarp.

关 键 词：表儿茶素(EC) 荔枝 多酚氧化酶(PPO) 酶促氧化 抑制作用 

分 类 号：Q554[生物学—生物化学] S667.1[农业科学—果树学]