Cu~(2+)、Pb~(2+)和Cd~(2+)对荞麦种子中抗氧化酶活性的影响

近年来,有关荞麦降血脂、降血糖和抗衰老等的作用引起国内外生化、营养和医药学界的普遍关注1,2].一些研究表明,荞麦中富含超氧化物歧化酶(SOD)、过氧化氢酶(CAT)和谷胱甘肽过氧化物酶(GSH-Px)等能够清除机体内超氧阴离子自由基(O-·2)、羟自由基(·OH)和H2O2等有害物质?..

Effect of Cu~(2+),Pb~( 2+) and Cd~(2+) on Antioxidant Enzyme Activities in Buckwheat Seed

Effects of three metal ions (Cu 2 ,Pb 2 and Cd 2 ) on antioxidant enzyme activities in buckwheat seed extracts (BSE) were reported. The results showed that the enzyme activities of superoxide dismutase (SOD), catalase (CAT) and glutathion peroxidase (GSH Px) in BSE were inhibited partly in the presence of Cu 2 ,Pb 2 and Cd 2 ions, and the inhibition in common buckwheat extracts (CBE) was greater than that in tartary buckwheat extracts (TBE). Antioxidant enzymes activities were seriously inhibited by Cd 2 in BSE. When the concentration of Cu 2 was 50mmol/L in the reaction system, the activities of SOD, CAT and GSH Px in CBE were 60 0%, 24 6% and 11 6% of the initial values respectively, and in TBE,they were 63 0%, 28 2% and 17 1%. While the concentration of Cd 2 was 20 mmol/L, the remaining activities of three enzymes in CBE were 49 1%, 4 6% and 1 4%, and in TBE the remaining activities of three enzymes were 50 0%,6 2%and 3 9% respectively. SOD in BSE was heat stable remarkably, but the enzyme activity was lost partly in the presence of the three ions. These results suggested that these metal ions mightbe substituted for the zinc in SOD, and effected the enzyme stability.