Determination of Oleanolic Acid and Ursolic Acid in Oldenlandia diffusa and Its Substitute Using High Performance Liquid Chromatography

ZHITAO LIANG, ZHIHONG JIANG, DAVID WANGFUN FONG AND ZHONGZHEN ZHAO*

School of Chinese Medicine, Hong Kong Baptist University, Kowloon, Hong Kong, China

(Received: November 2, 2007; Accepted: May 1, 2008)

ABSTRACT

   An improved quality evaluation method for Oldenlandia diffusa (Willd.) Roxb. and its substitute was established by a welldefined high performance liquid chromatographic (HPLC) method. Firstly, a complete separation of oleanolic acid and ursolic acid was successfully achieved by optimizing the mobile phase systems based on previous reports. The extraction method was optimized and the less toxic solvent was selected for extraction. The systematic survey of herbal markets has shown that O. corymbosa (L.) Lam are widely available and used indiscriminately as O. diffusa. Twenty-seven samples of O. diffusa and seventeen samples of O. corymbosa were analyzed. The results showed that the contents of oleanolic acid and ursolic acid in O. diffusa were generally lower by almost two times than those in O. corymbosa. Moreover, the contents of oleanolic acid and ursolic acid between the fresh and dry samples were compared. The introduction of quality evaluation method could be useful for the species identity and quality evaluation of O. diffusa and its substitute.

Key words: Oldenlandia diffusa, Oldenlandia corymbosa, oleanolic acid, ursolic acid, HPLC