硝酸镧[La(NO_3)_3]对巴西橡胶树胶乳活性氧清除系统的影响

比较了巴西橡胶树在施用了硝酸镧、乙烯利、乙烯利和硝酸镧混合剂后胶乳中的过氧化物酶(POD)活性、超氧化物歧化酶(SOD)活性、抗坏血酸(Vc)和硫醇含量。结果表明,乙烯利加硝酸镧处理的胶乳的POD比活力显著低于只施用了乙烯利的处理的胶乳;并且只施用硝酸镧处理的胶乳的SOD比活力极显著高于只施用乙烯利的。硝酸镧处理下胶乳Vc和硫醇含量没有提升,甚至胶乳的Vc含量降低;且硝酸镧与乙烯利联用不影响胶乳Vc含量;硝酸镧与乙烯利联用下胶乳硫醇含量不高于乙烯利单独施用的。硝酸镧处理并没有提高胶乳非酶促系统的清除活性氧能力,可能主要依靠提高胶乳活性氧酶促清除系统来提高其抗氧化性。

Effect of Lathanum Nitrat [La(NO3)3] on the Active Oxygen Scavenging System of Hevea Brasiliensis Latex

The latex's activity of peroxidase(POD) and superoxide dismutase (SOD), content of ascorbic(Vc) and thiols in the treatments of ethephon, lathanum nitrate and mixture of ethephon and lathanum nitrate in Hevea Brasiliensis trees were studied. It was found that the POD specific activity in the ethephon with lanthanum nitrate treatment was significantly lower than that of ethephon only. The latex SOD specific activity in lanthanum nitrate treatment was significantly higher than that of ethephon only. Latex Vc and thiols content did not increase, even reduced in lanthanum nitrate treatment. Lanthanum nitrate combined with ethephon had no effect on latex Vc content. Lanthanum nitrate combined with ethephon did not increase latex thiols content than that of ethephon treatment. The antioxidant capacity of rubber trees in lanthanum nitrate treatment may be mainly improved by enzymatic oxygen scavenging systems, not by the non-enzymatic systems.