黄芩茎叶黄酮作为GABAA受体BZD结合部位配体

摘要

Aim To search for bioactive constituents of the aerial part of Scutellaria baicalensis Georgi.Methods Various column chromatography with silica gel,D101 resin,Sephadex LH-20 and polyamide were employed for the isolation and purification of bioactive constituents.Results Seven flavonoids(wogonin,chrysin,5,6,7-trihydroxy-4′-methoxyflavone,carthamindin,isocarthamidin,scutellarein,chrysin 7-O-β-D-glucuronide)were isolated from a water extract of the leaves of Scutellaria baicalensis Georgi.Among the isolated compounds,chrysin showed a high affinity to the benzodiazepine site of the GABAA receptor with an IC50 value of 0.67 μmol/L.Based on binding to BZD-S,the order of the affinity among these compounds was chrysin＞wogonin＞carthamidin＞scutellarein＞5,6,7-trihydroxy-4′-methoxyflavone＞isocarthamidin＞chrysin 7-O-β-D-glucuronide.%目的从黄芩地上部分中寻找活性成分.方法利用各种柱色谱(硅胶、Sephadex LH-20、D101大孔吸附树脂和聚酰胺)分离黄芩地上部分的活性成分.结果从黄芩地上部分的水提取物中分离得到7种黄酮类化合物.其中白杨素对GABAA受体的BZD结合部位有较高的亲和力,其IC50值为0.67 μmol/L.7种黄酮类化合物亲和力的排列顺序为:白杨素＞汉黄芩苷元＞红花素＞黄芩素＞5,6,7-三羟基-4′-甲氧基黄酮＞异红花素＞白杨素-7-葡萄糖醛酸苷.