基于循环伏安法研究槲皮素醌与亲核物质的相互作用  

Interaction between Quercetin Quinone and Nucleophiles Based on Cyclic Voltammetry

作　　者：李玉婷 范美琪 余祥英 詹士杰 朱杰[1] 李琳[1] Li Yuting;Fan Meiqi;Yu Xiangying;Zhan Shijie;Zhu Jie;Li Lin(Engineering Research Center of Health Food Design&Nutrition Regulation,School of Chemical Engineering and Energy Technology,Dongguan University of Technology,Dongguan 523808,Guangdong)

机构地区：[1]东莞理工学院,食品营养健康工程与智能化加工研究中心,化学工程与能源技术学院,广东东莞523808

出　　处：《中国食品学报》2020年第4期57-65,共9页Journal of Chinese Institute Of Food Science and Technology

基　　金：国家自然科学基金青年科学基金项目(31701727);国家自然科学基金面上项目(31671961)。

摘　　要：多酚氧化形成的醌类物质作为强亲电体可能与食品体系中多种亲核物质作用,进而引发系列营养与安全问题。利用电化学工作站研究了酸性(pH 5.0)、中性(pH 7.0)和碱性(pH 8.0)条件下槲皮素醌与5种氨基化合物、2种巯基化合物以及牛血清白蛋白(BSA)的相互作用。结果表明:槲皮素醌在pH 7.0或pH 8.0条件下与8种亲核物质的互作效率显著高于pH 5.0;相同作用条件下,槲皮素醌与巯基化合物互作效率显著优于氨基化合物;在pH 7.0、扫描速率10 mV/s的条件下,槲皮素醌(0.08 mmol/L,以槲皮素计)与5种氨基化合物(16.0 mmol/L)互作效率排序为:L-赖氨酸(55.13%±5.37%)>L-精氨酸(39.58%±4.64%)>L-甲硫氨酸(17.80%±2.72%)>甘氨酸(~0.00%)≈Nα-乙酰-L-赖氨酸(~0.00%),槲皮素醌(0.08 mmol/L,以槲皮素计)与2种巯基化合物及BSA(0.048 mmol/L)互作效率排序为:L-半胱氨酸(63.17%±1.51%)>Nα-乙酰-L-半胱氨酸(54.28%±2.60%)>BSA(37.55%±5.98%)。研究表明:槲皮素氧化形成的醌类物质可以化学改性蛋白质,消耗体系必需氨基酸。O-benzoquinones,generated by the oxidation of polyphenols,are highly electrophilic compounds and may react with many kinds of nucleophiles in food systems,and therefore cause nutrient losses and food safety problems.The interaction of quercetin quinone with five kinds of amines,two kinds of thiols and bovine serum albumin(BSA)were investigated at pH 5.0,7.0 and 8.0 by electrochemical workstation.Quercetin quinone reacted with selected nucleophiles more efficiently at pH 7.0 and 8.0 than that at pH 5.0.In addition,reaction of quercetin quinone with thiols was found to be faster than that with amines.At pH 7.0 and scan rate of 10 mV/s,amines(16.0 mmol/L)reaction with quercetin quinone(0.08 mmol/L)followed the order:L-lysine(55.13%±5.37%)>L-arginine(39.58%±4.64%)>L-methionine(17.80%±2.72%)>glycine(~0.00%)≈Nα-acetyl-L-lysine(~0.00%).Thiols(0.048 mmol/L)reaction with quercetin quinone(0.08 mmol/L)under the same conditions followed the order:L-cysteine(63.17%±1.51%)>Nα-acetyl-L-cysteine(54.28%±2.60%)>BSA(37.55%±5.98%).These data proved that O-benzoquinone formed by the oxidation of quercetin could modified proteins and eliminated essential amino-acids.

关 键 词：槲皮素 邻苯二醌 循环伏安法 氨基化合物 巯基化合物 

分 类 号：TS201.2[轻工技术与工程—食品科学] TS202.3[轻工技术与工程—食品科学与工程] O657.1[理学—分析化学]