葡萄糖-甘氨酸美拉德反应产物对脂肪氧合酶的抑制作用研究

以葡萄糖和甘氨酸为原料制备美拉德反应产物（Glu/Gly-MRPs）,研究其对大豆脂肪氧合酶（LOX）的抑制作用以及机理。结果表明:随着反应中甘氨酸浓度、反应初始pH、反应温度和反应时间的增大,Glu/Gly-MRPs的褐变程度加深,pH下降,对LOX的抑制作用增强;当甘氨酸浓度大于0.6mol/L、反应体系初始pH高于8.0、反应温度高于110℃、反应时间长于3h时,MRPs对LOX的抑制率均趋于稳定值（80%¹00%）。Glu/Gly-MRPs对LOX酶促反应的迟滞时间具有延长作用,通过Lineweaver-Burk双倒数法确定Glu/Gly-MRPs对LOX的抑制类型为混合型抑制。 

Inhibition of lipoxygenase by Maillard reaction products from glucose and glycine

The Maillard reaction products ( MRPs) were prepared from glucose and glycine.The inhibitory effect of MRPs on purified soybean lipoxygenase ( LOX) was studied.The results showed that as the glycine concentration, initial pH, reaction time and temperature increased, the final pH decreased, the browning of the reaction system deepened and the inhibitory activity enhanced. When the glycine concentration was over 0.6mol /L, the initial pH was over 8.0, the reaction temperature was over 110℃ and the reaction time exceeded 3h, the inhibition rate of MRPs reached a stable level ( 80% ~100%) . Meanwhile, Glu /Gly- MRPs extended the lag time of the enzymatic reaction considerably.The Lineweaver-Burk plots showed that Glu /Gly-MRPs were mixed-type inhibitor of LOX.