Research Article Efficacy of Plectranthus amboinicus (Lour.) Spreng in a Murine Model of Methicillin-Resistant Staphylococcus aureus Skin Abscesses

Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Thepresentwork aimed to evaluate the effectiveness ofPlectranthus amboinicus (Lour.) Spreng againstMRSAclinical isolates.The in vitro antimicrobial activity of the hydroalcoholic extract (HE), the ethyl acetate (EA) fraction and its subfractions were determined by broth microdilution and bioautography against MRSA clinical isolates. The microdilution checkerboard method was used to assess in vitro drug combination studies. To induce abscess formation, bacterial suspensions were added to Citodex and inoculated subcutaneously intomale Swiss mice.The treatment protocol consisted of 2 doses of HE, the EA fraction or vancomycin introduced intraperitoneally into mice 3 and 12 h after infection. The EA fraction and its subfractions presented the lowest minimal inhibitory concentrations (MIC, 0.25 to 0.5mg/mL). The plant samples were bacteriostatic at 2x and 4x MIC and bactericidal at 100mg/mL