Phytochemical investigation and anti-microbial activity of combretum paniculatum stem bark

Abstract

Traditional medicine plays a significant role in the health care system. C. paniculatum (in afan oromo ”Baggii”) is one of the herbal medicines commonly practiced by traditional healers for the treatment of various infectious diseases. The main objective of this study was to carry out on phytochemical investigation of C. paniculatum stem barks and evaluation of its antimicrobial activities. The air dried plant sample was sequentially extracted with petroleum ether, chloroform, acetone and methanol. The crude extracts were tested for their antimicrobial activity against four bacterial strains (E. coli, B. subtilis, S. aureus and P. aeruginosa) and two fungal strains (Fusarium spp, and S. cerevisiae) using disc diffusion method. The extracts were observed for their number of phytochemical components by using TLC analysis and the chloroform extract was subjected to column chromatography packed with silica gel. The column was eluted with petroleum ether, with increasing gradient of ethyl acetate. The isolated compounds were characterized on the bases of NMR spectroscopic data and comparison with literature. Extraction yield of crude extracts resulted with 0.45%, 0.5%, 1.1% and 2.6% for petroleum ether, chloroform, acetone and methanol respectively. Among 125, fractions 25-41 and 64-97 provide two compounds, compound 1(8.4 mg) and compound 2(6.8 mg). The two isolated compounds were characterized and deduced to be cholest-5-en-3-ol and dihexyldecyl succinate respectively. In previous study compound 1was isolated and reported from the leaves part of the plant where as, compound 2is isolated for the first time from this species. Isolated compounds showed marginal antibacterial and little antifungal activities. Antimicrobial activity of crude extract was superior than isolated compounds. Generally, the superior activity of the crude extracts than the pure compound may be due to synergetic effects of several compounds present in the crude extract.