【摘要】 氧化剂、还原剂处理前后，Ｌ－ＳＯＤ的活性及紫外光谱发生变化，Ｈ２Ｏ２使Ｆｅ（Ⅲ）吸收增强，同时钝化Ｌ－ＳＯＤ的活性；加入保险粉后，Ｌ－ＳＯＤ重新活化，Ｆｅ（Ⅲ）吸收减弱．ＮＥＭ封闭Ｃｙｓ后，Ｌ－ＳＯＤ紫外吸收谱发生变化，且活性减弱．说明Ｆｅ辅基及Ｃｙｓ是活性发挥的必需基团．更多还原

【Abstract】 SOD is classified into three groups with respect to the metal ion in the enzyme.They are Cu·Zn SOD,Fe SOD and Mn SOD.The common character among them is related to the alternative reduction and reoxidation of the metal ion in the active site.SOD activity in Rose Fruit is very high.By systematic analysis,the substance of scavenging O - 2 was found to be mainly a material with low molecular weight termed as L SOD.SOD or L SOD might play a significant,even vital role in protecting the organism aganinst the damaging effects of the superoxide radical.L SOD activity of rose fruit was lost by adding of oxides (H 2O 2) and partly recovered by adding reductants.In ultraviolet spectra,Fe(Ⅲ) absorption peak at 350 nm appeared as H 2O 2 was added in and disappeared by reduction.After the sulfhydryl groups were modified by NEM,SOD activity was damaged or disappeared and the characteristic ultraviolet spectra at 310 nm were different.It is suggested that cys SH is important to the L SOD activity and the reaction of Fe 2+ Fe 3+ is also related to the SOD activity.更多还原