Abstract

Objective: To determine the chemical constituents and antimicrobial activity of the hexane leaf extract of Anisopus mannii against a wide range of human pathogenic microorganisms.
Methods: The chemical constituents of the hexane leaf extract was determined using gas chromatography-mass spectrometry (GC-MS) analysis; and the antimicrobial activity was evaluated on clinical susceptible and resistant bacterial and fungal isolates using the disc diffusion and broth micro dilution methods.
Results: GC-MS analysis of the hexane leaf extract revealed 32 compounds, representing 73.8% of the identified components. The major compounds were hexadecanoic acid, ethyl ester (34%), oxirane, hexadecyl- (11%) and 9, 12, 15-octadecatrienoic acid, ethyl ester, (Z, Z, Z) (9.6%). Results from the antimicrobial activity demonstrated higher inhibition zones against B. cereus (29 mm), followed by S. pyogenes (28 mm). Other notable inhibitions were observed with E. faecalis (27 mm), P. vulgaris (26 mm) and MRSA (25 mm). The MIC values ranged from 0.625 mg/mL to 1.25 mg/mL while the MBC/MFC values ranged from 2.5 mg/mL to 5.0 mg/mL.
Conclusion: These results support the traditional use of the plant and demonstrate the huge potential of A. mannii as a source of antimicrobial compounds.

Key words: Anisopus mannii, hexane extract, GC-MS, antimicrobial activity