Protocatechuic acid and saponin mixture from Steganotaenia araliacea stem bark

Steganotaenia araliacea Hochst (Apiaceae / Umbelliferae) is used in East and West African ethnomedicine for treating gastro-intestinal disorders, peptic ulcer, rheumatism and various diseases of microbial origin. The plant was therefore investigated for its chemical constituents while testing for possible antimicrobial, antioxidant, spasmolytic and anti-inflammatory activities. Through bioactivity-driven fractionation, protocatechuic acid was isolated from the ethyl acetate fraction as the main antimicrobial (agar diffusion) and antioxidant (radical scavenging-DPPH) principle. The crude extract exhibited spasmolytic activity, which was found to reside exclusively in the aqueous fraction. Further fractionation of the aqueous fraction yielded a saponin mixture. The observed spasmolytic effect was found to be antihistaminic rather than anticholinergic. The saponin mixture also demonstrated significant anti-inflammatory activity. At a dose of 1 mg/kg i.p. it gave a 77.7% inhibition of carrageenan-induced rat-paw oedema. Key words: Steganotaenia araliacea; Saponins; Antimicrobial; Antioxidant; Spasmolytic; Antiinflammatory Nig. J. Pharm. Res. 3(1) 2004: 9-1