Quantification of catalpol in root of Rehmannia glutinosa varieties 19 collected in Phu Tho province by high-performance liquid chromatography

Abstract

The active ingredient catalpol in the Rehmannia glutinosa variety 19 roots is an important chemical component. Catalpol has hypoglycemia, diuretic, and laxative effects; it is used to support the treatment of diabetes, ischemic cerebral, and dementia, and it is regulated by Vietnamese Pharmacopoeia V (2017) as a marker to check the quality of medicinal herbs. This study aimed to develop a procedure for quantifying catalpol in the root of Rehmannia glutinosa varieties 19 by highperformance liquid chromatography (HPLC) to evaluate the quality of medicinal herbs. The research results have
selected suitable chromatographic conditions using the Gemini C18 column (250x4.6 mm, 5 µm), detector at 210 nm, mobile phase acetonitrile - phosphoric acid 0.1%, and flow rate at 0.6 ml/min. The peak area and catalpol concentration have a strong linear correlation with r=0.9999, Y = 21887X + 26213. The procedure has good accuracy and repeatability with a relative standard deviation (RSD) <2%. Quantitative results of catalpol in the root of the R. glutinosa varieties 19 reached 1.25%. The HPLC method is suitable for quantifying catalpol in the root of R. glutinosa varieties 19.