Fig. 2

Chemical profiles of the YK formula and their ingredients. The mobile phase systems are toluene, ethyl acetate, and formic acid (70:30:1) (A) and hexane and ethyl acetate (2:1) (B). Track No. 1, the YK formula; Track No. 2, the root of S. androgynous and B. androgyna; Track No. 3, the root of R. nasutus; Track No. 4, the root of M. vitifolia; Track No. 5, the root of D. volubilis; Track No. 6, the root of A. viridiflora; Track No. 7, the root of T. triandra; Track No. 8, the root of C. sinensis; Track No. 9, the root of C. aurantifolia; Track No. 10, the root of C. quadrangulare; Track No. 11, the root of M. cochinchinensis; Track No. 12, the root of G. zeylanicum; Track No. 13, the root of S. dichotomus/S. benthamianus; Track No. 14, the stem of H. formicarum; and Track No. 15, the root of C. bonduc