Effect of Stem Bark Extracts of Enantia chloranta on Some Clinical isolates

Abstract

Studies on antimicrobial activity of water, methanol and ethanol extracts of the stem bark of Enantia chlorantha, was carried out by the agar ditch diffusion and tube dilution methods. The clinical isolates used include; Staphylococcus aureus, Streptococcus pyogenes, Shigella sonnei, Proteus mirabilis, Klebsiella pneumoniae, Salmonella typhi, Pseudomonas aeruginosa, Aspergillus niger, and Candida albicans. The isolates were obtained from the Department of Medical microbiology and Parasitology of the University of Ilorin Teaching Hospital. Crude extracts of all solvents used inhibited the growth of all the isolates tested, except Pseudomonas aeruginosa . The Minimum Inhibitory Concentration (MIC) ranged between 25mg/ml to 150mg/ml depending on isolate and extracting solvent. Ethanolic extracts showed greater antimicrobial activity than the other two solvents. The killing rate of the Minimum Bactericidal Concentration (MBC) of the ethanolic extract on S. aureus and P.aeruginosa was 2½hr, and 3hr respectively. Temperature stability study showed that the extracts are stable and active over a temperature range of 30 to121^oC.

Key words: Enantia chlorantha, antimicrobial property, plant extract