茶鲜叶摊放过程中脂质过氧化作用特点初探

对新鲜茶叶在摊放过程中的失水率、细胞膜透性、三种保护酶（ＳＯＤ，ＣＡＴ，ＰＯＤ）活性及脂质过氧化产物丙二醛（ＭＤＡ）含量的变化及其相互关系进行了研究．结果表明，随着摊放时间的延长和叶片失水程度的增加，鲜叶内ＳＯＤ，ＣＡＴ活性先增强然后迅速减弱，ＰＯＤ活性则一直保持增强的趋势，叶片细胞膜透性和ＭＤＡ含量则不断上升．反映出茶鲜叶在摊放过程中脂质过氧化作用不断加剧，并且其增加速率与保护酶活性变化有一定相关，这在一定程度上意味着茶鲜叶适度摊放的化学实质与脂质过氧化作用有关

Preliminary study on lipid peroxidation of tea fresh leaves during spreading.

The variations of rate of moisture lose, the relative permeability of membrane, activities of endogenous protective enzymes, such as superoxide dismutase (SOD), catalase (CAT), peroxidation (POD), membrane lipid peroxidation were studied with the aim of understanding the relationship among these factors during the spreading of tea fresh leaves. The results showed that activities of SOD and CAT increased at first and then decreased sharply, but POD activity increased continiously during spreading. Permeability of plasma membrane and malondialdehyde (MDA) contents increased while time going of spreading and the increases of moisture lose. These results suggested that a correlationship might be exist between chemical mechanism of spreading of tea fresh leaves and lipid peroxidation.