Received: 21 July 2018 Accepted: 20 Ausgust 2018 Published: 01 September 2018
Microdesmis puberula is a plant that is used in traditional medicine for the treatment of diarrhea, stomachache, intestinal worms, menstrual complaints, sterility, miscarriage, loss of virility and venereal diseases, treat skin conditions, renal pain, severe headache, erectile dysfunction, and snake bite. In this work, methanol and petroleum ether extracts of the stem of Microdesmis puberula were evaluated for phytochemical constituents, antimicrobial activity and antioxidant activity. DPPH scavenging assay and total antioxidant capacity were used for the determination of the antioxidant activity. The agar well diffusion method was used to determine the antimicrobial activities of the extracts against the test organisms, Klebsiellapneumonia, Bacillussubtilis, Salmonella typhi, Enterococcus faecalis, Neisseria gonorhoeae, Escherichia coli, Pseudomonas aeruginosa, Streptococcus pyrogenes, Staphylococcus aureus and Candida albicans. The broth dilution method was used to determine the minimum inhibitory concentrations (MIC) of the methanol and petroleum ether extracts. The methanol extract exhibited antimicrobial activity against both Gram-positive and Gram-negative test organisms with zones of growth inhibition ranging from 12 to 16 mm in the agar well diffusion test, but the petroleum ether did not exhibit antimicrobial activity as it recorded no zone of growth inhibition. The methanol extract was active against the test organisms with MIC range of 6.25 to 12.5 mg/mL and that of petroleum ether ranged from 50 to 200 mg/mL. The reference drug showed activity between 1.56 to 25 mg/mL. The IC50 of the methanol and petroleum ether extract, and the reference drug with regard to the DPPH scavenging activity, were 1.1µg/mL, 1.2 µg/mL and 0.2 µg/mL respectively. Both the methanol and petroleum ether extracts exhibited antimicrobial and antioxidant activity.