决明子茶提取物中黄酮含量的测定及抗自由基活性研究

Determination of Total Flavonoid Content and Anti-free Radical Activity of Juemingzi(Cassia obtusifolia L.seed)Tea Extracts

以水、不同含量乙醇为溶剂,采用超声、回流等方法提取决明子茶中的总黄酮,采用亚硝酸钠-氯化铝法,通过紫外分光光度计在494 nm处测定样品吸收,计算总黄酮含量;采用DPPH法研究提取物抗自由基活性。研究发现超声和回流提取均含有一定量的黄酮,采用水回流提取的含量最低为3.39%,55%醇超声提取的含量最高为6.10%。决明子醇提取物对DPPH自由基有较好的清除作用,55%醇回流提取物自由基清除率为71.90%。

The total flavonoid of cassia seed tea were extracted with water or different ethanol water solution by ultrasonic or reflux. The total flavonoid contents were detected with absorption spectrophotometer in 494 nm by using NaNO2-AlCl3 method. The anti-free radical activity of the extracts was measured by using DPPH method. We found the flavonoid were detected in all of the extracts. The total flavonoid content in water extract by reflux was 3.39%, which was the lowest content.And that in 55%ethanol water solution extract by ultrasonic was 6.10%, which was the highest content. The extracts showed free radical scavenging activity to DPPH radical. And that in 55%ethanol water solution extract free radicals activity by reflux was 71.90%.