[关键词]
[摘要]
本文运用配位效应将木犀草素与金属离子Zn2+和Mn2+反应生成了木犀草素配合物,采用了红外、紫外、热重及元素分析对配合物进行了结构表征,同时研究了对黄嘌呤氧化酶的抑制作用,比较了木犀草素及其配合物抑制能力的大小,确定了对黄嘌呤氧化酶的抑制作用类型。结果表明,木犀草素与金属离子Zn2+和Mn2+发生了配位反应,形成了稳定的配合物,配合位点位于A环的5-OH及C环的4-C=O处。相比于木犀草素,木犀草素配合物对黄嘌呤氧化酶表现出更好的抑制效果,通过固定黄嘌呤底物浓度为0.6 mmol/L,酶浓度对酶活力作图可知,木犀草素及其配合物对黄嘌呤氧化酶的抑制类型均属于可逆抑制,通过固定黄嘌呤氧化酶浓度为10 μg/mL,用Lineweaver-Burk双倒数作图,木犀草素及其配合物对黄嘌呤氧化酶的抑制类型表现为竞争性抑制。
[Key word]
[Abstract]
The coordination effect was used to synthesize luteolin complexes between luteolin and metal ions Zn2+ and Mn2+, and the complexes were examined by ultraviolet UV-visible spectroscopy, infrared spectroscopy, thermogravimetric-differential scanning calorimetry, and elemental analysis techniques. Moreover, the inhibition of xanthine oxidase by the luteolin complex was studied, the inhibitory capacities of luteolin and its complexes were compared, and the type of inhibition of xanthine oxidase was determined. The results indicated that coordination reactions occurred between luteolin and the metal ions Zn2+ and Mn2+ to form stable complexes. The chelation site was located at the 5-OH of ring A and 4-C=O of ring C. Compared to luteolin, its complexes exhibited a better inhibitory effect on xanthine oxidase. When the xanthine substrate concentration was 0.6 mM, the graph of enzyme concentration versus enzyme activity showed that the types of inhibition by luteolin and its complexes were reversible. When the concentration of xanthine oxidase was 10 μg/mL, the double reciprocal Lineweaver-Burk plot showed that the types of inhibition by luteolin and its complexes were competitive.
[中图分类号]
[基金项目]
国家自然科学基金项目(31371743);广州市产学研协同创新重大专项项目(201508020086);广东省应用型科技研发专项资金项目(2015B020230001)