Evaluation of the antibacterial activity of the aqueous residual extract of the bark of Bridelia ferruginea Benth. on methicillin-resistant Staphylococcus aureus (MRSA)

The present study was carried out to evaluate the antibacterial activity of the aqueous residual extract of Bridelia ferruginea against clinical strains of methicillinresistant Staphylococcus aureus (MRSA) isolated from various biological products.Well diffusion and liquid microdilution methods were used for susceptibility testing and determination of MICs and BMCs.Tests were performed on 11 MRSA strains isolated from patients and one reference strain (ATCC 25923).Bridelia ferruginea is used in Africa to treat a number of diseases.The aqueous residual extract of the stem bark of this plant showed antibacterial activity on the bacterial strains tested, with zones of inhibition ranging from 8.00 0.00 mm to 26.00 0.00 mm at 100 mg/ml.MIC values ranged from 1.56 to 6.25 mg/ml.This extract showed bacteriostatic activity on all the MRSA strains tested.Phytochemical analysis showed the presence of polyphenols, flavonoids, gallic tannins and saponosides in the aqueous residual extract.This could justify the antibacterial activity and use of Bridelia ferruginea stem bark in the treatment of various meticillin-resistant Staphylococcus aureus infections.