ABSTRACT

Photochemistry of Acalypha wilkisiana magmala leaf was studied as well as an evaluation of antimicrobial activities of the leaf extracts in different solvents, against Methycilin Resistant Staphylococcus aureus (MRSA) from clinical samples. Extracts were obtained in water, ethanol and ethyl acetate and their yield, phytochemical content and antimicrobial activity were determined. Results showed yields of 11.62, 16.43 and 8.97% in water, ethanol and ethyl acetate respectively. Phytochernical composition showed Tannin (0.05% to 0.96), alkaloid (0.97 to 1.97), phenol (0.07 to 0.33), saponin (0.15 to 0.55) and flavonoid (0.15 to 0.27) percent. Hydrogen cyanide (HCN, 0.00 — 2.48mg/kg) was highest in the water extract. While the other phytochemicals had varied highest concentrations in the different solvents. Variations were also recorded in the antimicrobial activity. of extracts against the aphyIococcus aureus isolates. Water extract recorded the highest mean diameter of inhibition of 15.17mm (19.0mm to 20.3mm) while ethyl extract had the least inhibition of 13.1mm (9.0 to 16.7mm). All the extracts had lower inhibition relative to the standard drug (vancomycin) which recorded 18.28mm. Average resistance of 15% and 10% were exhibited by the isolates against the water extract whereas no resistance was recorded with ethanol extract and the standard drug (Vancothycin). Also 75% susceptibility was recorded for ethanol extract as against 65% each for water and thyl acetate extracts. The minimum inhibition concentrations (MIC) was I 00mg/mi for ethyl acetate extract 50mg/nil for water and ethanol extracts each. Again, the minimum bactericidal concentrations (MBC) of the extracts 250mg/mi, 300mg/nil and 350mg/mi for ethanol, water and ethyl acetate extracts respectively