Determination of chlorogenic acid in three species of cocklebur fruits from different regions of China by HPLC method

Objective:To establish a HPLC method for the determination of chlorogenic acid in cocklebur fruits,and to investigate the content of chlorogenic acid in three species of cocklebur fruits collected from different regions of China.Methods: The determination was performed on Zorbax SB-C18 column(250 mm×4.6 mm,5 μm) with the temperature set at 25 ℃.The mobile phase consisted of methanol-0.5% phosphoric acid solution at a flow rate of 0.8 mL/min.The detection wavelength was 327 nm.Results: The regression equation of chlorogenic acid was Y=2.135 7 X-120(r=0.999 8,n=5).The linear range of chlorogenic acid was 200-1 000 ng and the average recovery was(98.58±1.16)%(n=9).The contents of chlorogenic acid in Xanthium sibiricum samples from 11 locations were conspicuously different,and they were higher than those in X.mongolicum and X.sibiricum var.subinerme samples.The content of chlorogenic acid was highest in cocklebur fruits from Ding'an in Hainan Province,which was(0.969±0.010)%.Conclusion: The method is proved to be simple,accurate and specific,and offers dependable evidence for the quality evaluation of cocklebur fruits.The interspecies and intraspecies differences of the content of chlorogenic acid are considerable.The cocklebur fruits from Ding'an in Hainan Province can be considered as the resource of high-grade medical material of cocklebur fruits.