Comparison of oleanolic acid content in Pfaffia glomerata from different habitats of Guangxi / 国际药学研究杂志

ABSTRACT

Objective: To establish a method for the determination of oleanolic acid(OA)in Pfaffia glomerata to compare the contents of OA in different parts of P. glomerata from Guangxi, China, with different growth years and different habitats. Methods: HPLC method was adopted. The determination was performed on Phenomenex Luna C18(250 mm×4.6 mm, 5 μm)column with mobile phase consisting of methanol-water-glacial acetic acid-triethylamine(28515 0.20.1, V/V) at the flow rate of 1.0 ml/min. The column temperature was set at 30℃. The detection wavelength was set at 210 nm, and the injection volume was 20 μl. The content of OA in P. glomerata was determined by the established method, and the extraction process of OA was optimized by the orthogonal test. Results: The linear range of OA was 0.0206-2.060 mg/ml(r2=1.0000). RSDs for the precision, repeatability and stability tests were all lower than 2%(n=6 or n=7). The average recovery of OA was 100.89%(RSD=1.69%, n=9). The optimum extraction conditions of OA were as follows 20-fold ethanol(80%, V/V), extracting for three times, refluxing 1.5 hour each time, and processing acid hydrolysis with 3.0% sulfuric acid(g/g)for 1 hour. Under these conditions, the OA had the highest extraction efficiency. The contents of OA in reed head, root, old stem, tender stem, leaf and flower of P. glomerata were 4.87, 4.61, 2.67, 0.99, 0.24 and 1.13 mg/g, respectively. The average contents of OA in the roots of P. glomerata aged 1, 2, 3, 4 and 5 years in Guangxi were 3.08, 4.07, 4.71, 4.62 and 4.46 mg/g, respectively. Conclusion: The established extraction process and detection method is suitable for the extraction and content determination of OA in P. glomerata. Although OA is distributed in all parts of P. glomerata, the contents significantly vary in different parts. The content of OA is highest in reed head and lowest in leaves. The OA content in P. glomerata becomes stable after 3 years of growth in Guangxi.