电位滴定法测定苦瓜中总生物碱的含量

摘要

苦瓜分别经酸水提取、乙醇回流提取、超声波提取和碱浸提取,得到的样品以电位滴定法滴定,以苦瓜中的奎宁为基准物计算苦瓜中总生物碱的含量,由此建立苦瓜中总生物碱的含量测定方法.结果表明:电位滴定法具有良好稳定性、灵敏度和重现性,检测结果稳定可靠,且测定操作简便,可用于苦瓜中总生物碱的定量分析.四种提取方法得到生物碱的含量分别为4.644、4.428、6.804和8.964 mg/g,适宜的提取方法为碱浸提取法.%Dried Momordica charantia L were extracted through HCl-water,ethanol refluxing,ultrasonic extract,and alkaline leaching-chloroform extraction.The alkaloids were calculated by reference material.The results showed that potentiometric titration method had good stability and high sensitivity and high reliability.It could be used as a quantitative analysis of total alkaloids in Momordica charantia L.Total alkaloids contents of the Momordica charantia L with four extracting methods were 4.644 mg/g,4.428 mg/g,6.804 mg/g and 8.964mg/g respectively.The optimal extracting method was alkaline leaching-chloroform extraction.