Jiangxi Key Laboratory of Natural Product and Functional Food, College of Food Science and Engineering, Jiangxi Agricultural University, Nanchang 330045, China.
Jiangxi Key Laboratory of Natural Product and Functional Food, College of Food Science and Engineering, Jiangxi Agricultural University, Nanchang 330045, China.
Int J Biol Macromol. 2024 Oct;277(Pt 1):134092. doi: 10.1016/j.ijbiomac.2024.134092. Epub 2024 Jul 25.
Inhibition of pancreatic lipase (PL) is a strategy to prevent obesity. The inhibitory effects of Flos Sophorae Immaturus (FSI) extract and its main flavonoid components, rutin and quercetin, on PL were investigated. The contents of rutin and quercetin in FSI extract were 44.10 ± 1.33 % and 6.07 ± 1.62 %, respectively. The IC values of FSI extract, rutin and quercetin on PL were 322, 258 and 71 μg/mL, respectively. Rutin and quercetin inhibited PL in a reversible and noncompetitive manner. The combination of rutin and quercetin exhibited synergistic inhibitory effects at low concentration. The binding of rutin/quercetin with PL caused the fluorescence quenching of protein. Fluorescence titration showed the binding affinity of quercetin with PL protein was stronger than that of rutin. Circular dichroism analysis showed the binding changed the secondary structure of PL with an increase in random coil and a decrease in α-Helix and β-Sheet. Molecular docking revealed that rutin and quercetin could interact with the amino acid residues around the catalytic site through multiple secondary interactions. In vivo studies showed that FSI extract can reduce fat absorption and promote fecal fat excretion through inhibition of PL activity, and the effects were mainly due to rutin and quercetin.
抑制胰脂肪酶（PL）是预防肥胖的一种策略。本研究考察了槐米提取物及其主要类黄酮成分芦丁和槲皮素对 PL 的抑制作用。槐米提取物中芦丁和槲皮素的含量分别为 44.10±1.33%和 6.07±1.62%。槐米提取物、芦丁和槲皮素对 PL 的 IC 值分别为 322、258 和 71μg/mL。芦丁和槲皮素以可逆和非竞争性方式抑制 PL。芦丁和槲皮素在低浓度时表现出协同抑制作用。芦丁/槲皮素与 PL 的结合导致蛋白荧光猝灭。荧光滴定表明，与 PL 蛋白的结合亲和力强于芦丁。圆二色性分析表明，结合改变了 PL 的二级结构，随机卷曲增加，α-螺旋和β-折叠减少。分子对接表明，芦丁和槲皮素可以通过多种二级相互作用与催化部位周围的氨基酸残基相互作用。体内研究表明，槐米提取物通过抑制 PL 活性减少脂肪吸收并促进粪便脂肪排泄，其作用主要归因于芦丁和槲皮素。
