野菊花中刺槐甙的库伦滴定法

野菊花Chrysanthemum indicum L.是一种常用中草药,对防治流行性脑脊髓膜炎、流感、高血压、肝炎、痢疾、痈疖疗疮有一定作用。最近还报道野菊花栓剂可用于治疗前列腺炎等症。野菊花的化学成分,据报道含有黄酮类化合物,已知的有刺槐甙(acaciin),水解后得刺槐素(acacetin),分子结构式为

COULOMETRIC TITRATION OF ACACIIN IN CHRYSANTHEMUM INDICUM

A method for the determination of acaciin in Chrysanthemum indicum was developed. It includes extraction, separation and determination of acaciin. The procedure is as follows:Weigh accurately 1 g of pulverized sample, put it in an extractor, extract the acaciin with methanol for 2 h on a boiling water bath, then concentrate to 10 ml.Spot exatctly 300 μl of this solution on a polyamide plate and chromatograph with CHCl₃MeOH-H₂O (9:1:0.1) as the developing solvent. Detect the spots under UV light, scrape the acaciin spot from the plate, put into the anodic compartment of an electrolytic cell containing the electrolytic solution, and titrate coulometrically using a suitable constant current.The results obtained by this method are in agreement with those by UV spectrophotometry.