杏仁种皮黑色素抑制晚期糖基化末端产物的研究

Inhibitory Effects of Melanin Derived from Apricot Testa on the Formation of Advanced Glycation End Products

建立牛血清蛋白-葡萄糖(BSA-Glucose)、牛血清蛋白-果糖(BSA-Fructose)和牛血清蛋白-丙酮醛(BSA-Methylglyoxal)的美拉德模拟反应体系,在体系中添加不同浓度的杏仁种皮黑色素,氨基胍(AG)作为阳性对照,37℃下反应,以荧光强度(Ex=370 nm,Em=440 nm)表示晚期糖基化末端产物(AGEs)含量,分析BSA-Glucose体系中蛋白质巯基、羰基含量变化,通过反相高效液相色谱/二极管阵列法(RP-HPLC-DAD)分析杏仁种皮黑色素对丙酮醛(Methylglyoxal,MGO)的清除效果。结果表明,杏仁种皮黑色素对BSAGlucose、BSA-Fructose、BSA-Methylglyoxal体系中AGEs的形成均有显著的抑制作用(P<0.05),抑制率最高分别达到73.81%、42.22%、38.57%。杏仁种皮黑色素能显著升高BSA-Glucose中蛋白质巯基含量(P<0.05),对MGO也具有清除作用,清除率随着时间的延长而升高,当反应24 h时,清除率达到最高,为63.54%。

The model system of bovine serum albumin - glucose （ BSA - Glucose） , bovine serum albumin - fructose （BSA -Fructose） and bovine serum albumin- methylglyoxal （BSA -Methylgl）;oxal） have been used to evaluate the effect of melanin derived from apricot kernel skin of AGEs formation with aminoguanidine （AG） as positive control. All samples were incubated at 37 %. The fluorescence intensities （Ex = 370 nm, Em =440 nm） were measured as the total AGEs content. Protein sulfhydryl and carbonyl contents were also determined. The MGO scavenging abilities of melanin derived from apricot kernel skin and AG were detected by reversed phase high - performance liquid chromatography / diode array detector （ RP - HPLC - DAD）. The results showed that melanin derived from apricot kernel skin had expressed an extra - strong inhibitory activity against the formation of AGEs （P 〈 0.05 ） in the three model systems, with the highest inhibition ratios as 73.81%, 42.22% and 38.57% respectively. Melanin derived from apricot kernel skin could significantly increase protein sulfhydryl content in BSA - Glucose （P 〈 0.05 ） and scaveng the MGO. The MGO scavenging ability of melanin derived from apricot kernel skin increased along with the reaction time. The highest scavenging ratio reached 63.54% after 24 h＇s reaction.