常春油麻藤花黄酮类化合物结构鉴定及抗氧化活性分析

摘要

目的：阐明常春油麻藤（Mucuna sempervirens）花中的黄酮类化合物及其抗氧化活性。方法：利用高速逆流色谱、制备型液相色谱等技术进行分离纯化,根据化合物的理化性质和波谱数据进行结构鉴定,并采用DPPH法测定其抗氧化活性。结果：分离得到8个化合物单体,鉴定为矢车菊3-O-6＇＇-O-α-鼠李糖-β-D-葡萄糖苷（cyanidin3-O-6＇＇-O-α-rhamnopyranosyl-β-D-glucopyranoside,I）、矢车菊3-O-β-D-葡萄糖苷（cyanidin 3-O-β-D-glucopyranoside,II）、槲皮素-3-O-β-D-葡萄糖苷（quercetin-3-O-β-D-glucopyranoside,III）、二氢槲皮素（dihydroquercetin,IV）、山奈酚（kaempferol,V）、异夏佛塔苷（6-C-β-L-arabinopyranosyl-8-C-β-D-glucopyranosyl apigeni,VI）、山奈酚-33-O-α-L-鼠李糖基-（1-6）-β-D-半乳糖苷（kaempferol-3-O-α-L-rhamnopyranosyl-（1-6）-β-D-galactopyranoside,VII）和山奈酚-3-O-α-L-鼠李糖基-（1-4）--β-D-葡萄糖苷（kaempferol-3-O-α-L-rhamnopyranosyl-（1-4）-β-D-glucopyranoside）,VIII）。其中黄酮I～V为主要的抗氧化物质,其抗氧化活性存在剂量效应关系;黄酮VI～VIII抗氧化活性较低。%Objective： To clarify the flavonoids and their antioxidant activities from the flowers of Mucuna sempervirens.Methods： High-speed countercurrent chromatography（HSCCC） and preparative HPLC were used to separate and purify the flavonoids.Their structural characterization was performed based on their physicochemical properties and spectral analysis.The antioxidant activities were evaluated by DPPH radical scavenging assay.Results： Eight compounds were isolated from the flowers of M.sempervirens,and identified as cyanidin3-O-6＇＇-O-α-rhamnopyranosyl-β-D-glucopyranoside（I）,cyanidin3-O-β-D-glucopyranoside（II）,quercetin-3-O-β-D-glucopyranoside（III）,dihydroquercetin（IV）,kaempferol（V）,6-C-β-L-arabinopyranosyl-8-C-β-D-glucopyranosyl apigeni（VI）,kaempferol-3-O-α-L-rhamnopyranosyl-（1-6）-β-D-galactopyranoside（VII）,and kaempferol-3-O-α-L-rhamnopyranosyl-（1-4）-β-D-glucopyranoside（VIII）,respectively.The flavonoids I through V were the major antioxidant components with a dose-effect relationship.The flavonoids VI through VIII revealed lower antioxidant capacity.Conclusion： This study provides an insight into the flavonoid composition and their antioxidant activities in the flowers of Mucuna sempervirens.