玄参主要环烯醚萜苷热稳定性研究

Thermostability of the main iridoid glycosides in Radix Scrophulariae

目的:研究玄参中各主要环烯醚萜苷在干燥过程和水浴加热过程中的稳定性。方法:将4等份玄参叶分别采用室温(20℃)干燥20d及40℃、60℃、80℃直接烘干,5等份玄参根冷浸液不同水浴温度(40℃、60℃、70℃、80℃、90℃)加热1h,HPLC法测定玄参中主要环烯醚萜苷桃叶珊瑚苷、哈帕苷、哈帕俄苷含量。结果:不同烘干温度下测得玄参叶中各环烯醚萜苷含量,以室温及40℃最低,60℃最高,但与80℃差异不明显;玄参根冷浸液不同水浴温度加热1h后,4种成分含量变化不显著。结论:玄参鲜药材干燥温度对其主要环烯醚萜苷含量影响很大,但提取过程中的温度对其影响不大。

Objective:To investigate the stability of the main iridoid glycosides in Radix Scrophulariae during drying and water-bath heating.Methods:Four equal portions of Radix Scrophulariae leaves were dried at room temperature(20℃) for 20 days,40℃,60℃,and 80℃,respectively,and five equal portions of cold extraction liquid of Radix Scrophulariae root were placed in water-bath with a temperature of 40℃,60℃,70℃,80℃,and 90℃,respectively,for 1 hour.High-performance liquid chromatography was used to measure the content of the main iridoid glycosides in Radix Scrophulariae,i.e.,aucubin,harpagide,and harpagoside.Results:Radix Scrophulariae leaves dried at room temperature and 40℃ had the lowest content of the iridoid glycosides,and those dried at 60℃ had the highest content,but with no significant difference from those dried at 80℃.There were no significant changes in the content of these four iridoid glycosides after the cold extraction liquid of Radix Scrophulariae root was placed in water-bath with different temperatures for1 hour.Conclusion:Drying temperature for fresh Radix Scrophulariae has a great impact on the content of the main iridoid glycosides,while temperature during extraction has little influence.