自氧化作用光度法测定鱼腥草中黄酮类化合物

Determination of flavonoids in houttuynia cordata thunb based on self-oxidation by spectrophotometry

在高温,酸性条件下，醇水提取鱼腥毕中黄酮类化合物黄酮类化合物中槲皮素的衍生物如芦丁、槲皮甙、全丝桃甙等水解为槲皮素，在碱性备件下，槲皮素易发生内氧化作用,其最终产物稳定，在320nm处有最大吸收，当槲皮素含量在4．0-20.0μg／mL范围内辽守朗伯一比尔定难，其表坦摩尔吸光系数为2．6×10L／mol／cm．其加标回收率为96.3％～103．8％，相时标；篷偏差（RSD）为1.9％～2.6％，经用于鱼腥草中黄胴类化各物仔苗的测定，结果符合分析要求.

Flavonolds in houttuynia cordata thunb were extracted through alcohol-water under the condition of high temperature and acid. Quercetin was obtained through the hydrolysis of quercetin dcriwttivcs in ltavonoids such as rutin, quercitrin, hyperin, etc. Quercctin was easy to undergo self-oxidation in the presence of the alkaline conditions. The final self- oxidation product was siable. The maximum absorption wavelength of the product was 320nm. Beer＇s law was obeyed wilhin the range of 4.0-20,0μg/mL for quercetin. The apparent molar absorptivity was 2.6- 10 ^4L/mol/cm. The recovery of quercetin was 96.3%-103.8%. The relative standard deviation（RSI）） of quercetin was 1.9%-2.6%, The method was applied for the determination offlavonoids in houtiuynia cordata thunb with satisfactory results.