Department of Biochemistry and Microbiology, Faculty of Science and Agriculture, University of Fort Hare, P/Bag X1314, Alice 5700, South Africa; Department of Microbiology, University of Venda, Thohoyandou, South Africa; Department of Biochemistry and Microbiology, University of Buea, Box 63, Buea, Cameroon
Adefuye, A.O., Department of Biochemistry and Microbiology, Faculty of Science and Agriculture, University of Fort Hare, P/Bag X1314, Alice 5700, South Africa; Samie, A., Department of Microbiology, University of Venda, Thohoyandou, South Africa; Ndip, R.N., Department of Biochemistry and Microbiology, Faculty of Science and Agriculture, University of Fort Hare, P/Bag X1314, Alice 5700, South Africa, Department of Biochemistry and Microbiology, University of Buea, Box 63, Buea, Cameroon
Medicinal plants have been age long remedies for human diseases because they contain components of therapeutic value. In this study, six solvent extracts [dichloromethane, ethyl acetate, acetone, ethanol, methanol (100%), and 40% methanol hydroxide] of the stem bark of Bridelia micrantha and ciprofloxacin were investigated for antimicrobial activity by the agar-well diffusion method against strains of Staphylococcus aureus NCTC 6571, Shigella sonnei ATCC 29930, Salmonella typhimurium ATCC 13311, Helicobacter pylori ATCC 43526, and Helicobacter pylori 252c. The most active extracts were assayed for MIC 50 using the 96-well microdilution technique and one way ANOVA test was used to determine if there was any statistically significant difference in the MIC 50 of the most active extracts and the control antibiotic (ciprofloxacin). Results obtained indicated that methanol was quantitatively the best solvent for extraction, while ethyl acetate was the least. Zone diameters of inhibition ranged from 0 to 28 mm for the six extracts and 29 to 38 mm for ciprofloxacin. Ethyl acetate and acetone extracts were the most active of all the extracts exhibiting a broad spectrum activity. However, Gram-positive bacteria were more sensitive compared to Gram-negative bacteria. The MIC 50 value ranged from 0.078 to 1.25 mg/ml and 0.078 to 0.625 mg/ml for the acetone and ethyl acetate extracts respectively, with no statistically significant difference in potency (p value = 0.187) when compared to ciprofloxacin. Our findings demonstrate the in-vitro antibacterial activity of the crude extracts of B. micrantha, and therefore provide preliminary scientific evidence to justify the use of the plant in traditional medicine. © 2011 Academic Journals.
acetic acid ethyl ester; acetone; alcohol; antiinfective agent; Bridelia micrantha extract; ciprofloxacin; dichloromethane; methanol; plant extract; unclassified drug; agar diffusion; antibiotic resistance; antimicrobial activity; article; bacterial virulence; bark; bioassay; Bridelia micrantha; concentration response; controlled study; drug efficacy; drug potency; drug screening; Euphorbia; Helicobacter pylori; IC 50; in vitro study; minimum inhibitory concentration; nonhuman; plant stem; Salmonella typhimurium; Shigella sonnei; Staphylococcus aureus; strain difference; Bacteria (microorganisms); Bridelia micrantha; Helicobacter pylori; Negibacteria; Posibacteria; Salmonella typhimurium; Shigella sonnei; Staphylococcus aureus