Abstract

ANTIMICROBIAL ACTIVITY OF LEAF EXTRACT OF MITRACARPUS HIRTUS (L) DC

Abbas A. Y.*, Abubakar M. G., Obieje B. I. and Farouq A. A.

ABSTRACT

Mitracarpus hirtus leaves have been used locally in Northern Nigeria for the treatment of skin diseases and other infectious diseases for a very long time. The current study evaluated the anti-bacterial and anti-fungal activities of hydro-methanolic extract and various organic solvent extracts of M. hirtus. Antimicrobial activities were determined using the agar ditch diffusion method. The mean lethal dose (LD50) was determined using the OECD procedure. The mean lethal dose (LD50) of the hydro-methanolic extract was found to be greater than 5000mg/kg. The hydro-methanolic extract further partitioned using hexane, ethylacetae, and saturated butanol. The highest activities were observed for hexane extract against Ps. aeruginosa (31 ± 3.52mm) and fungi pathogen T. rubrum (30 ± 0.57mm). The MIC, MBC and MFC of the hexane extract ranged between 1.56 to 12.5mg/ml and 3.13 to 50.0 mg/ml for the bacteria and fungi respectively. Phytochemicals analysis of the hexane extract revealed the presence of some bioactive components such as saponins, flavonoids, alkaloids, etc. Topical application of the hexane extract at 3000 mg/kg demonstrated better activity on the skin T. rubrum infected rabbits. The hexane extract was further fractionated using Column chromatography and thin layer chromatography. Fraction 3 gave the highest antibacterial and antifungal activities. This study revealed that hexane fraction 3 of M. hirtus leaf extract possesses significant antimicrobial activity and have the potential for the development of novel antimicrobial.

Keywords: Mitracarpus hirtus, antibacterial, antifungal, chromatography.