酸性染料比色测定玛咖总生物碱含量的条件考察

Determination of total alkaliods in Maca by acid dye colorimetry

以乌头碱为对照品,采用酸性染料比色法测定了玛咖总生物碱的含量,并对其显色条件进行选择。结果表明,玛咖生物碱含量测定的最佳条件为：乌头碱对照品在40~320μg范围内,pH4.0氢氧化钠-邻苯二甲酸氢钾缓冲液6 mL及其配置的0.5%溴甲酚绿显色剂2 mL,显色50 min,412 nm处检测。此法测得玛咖粉末中总生物碱含量约为4.65‰,且该法操作简便、精密度高、稳定性好、具良好的可重复性。

With the aconitine as reference,the paper established a method for the determination of total alkaloids in Maca by adid dye colorimetry and the conditions of this method were also purified.The linearity was established for the aconitine in the range of 40~320 μg.Best conditions of coloring were that pH4.0 sodium hydroxide-potassium acid phthalate buffer was 6 mL and 0.5% bromocresol green colour reagent 2 mL were added,for 50 minutes,and detect at 412 nm.It was about 4.65‰ of total alkaloids in Maca measured by this method.The research suggested that this method was simple,accurate,stable,and repeatable.