A comparative study on the vitro antimicrobial properties of Psidium guajava leaf extract vs Vancomycin on Methicillin Resistant Staphylococcus aureus (MRSA)

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Clinical Pharmacology


Anti-Infective Agents, Psidium, Plant Extracts, Vancomycin, Methicillin Resistant Staphylococcus aureus


The research was conducted to investigate antibacterial properties in a methanolic leaf extract of P. guajava against Methicilin Resistant Staphylococcus aureus (MRSA) and compare it to that of Vancomycin. Leaf extracts were obtained using a methanol solvent and analysis of its phytochemical properties revealed high levels of flavonoids, saponins, and tannins, compounds to which the antibacterial activity of P. guajava was attributed. The P. guajava leaf extract was serially diluted and was tested its antibacterial activity through Agar dilution method. In both methods, all concentrations of the leaf extract failed to show any inhibitory activity against MRSA, indicating resistance of the organism. The absence of antimicrobial activity of the methanol P. guava leaf extracts may be due to the resistance of the clinical strain, inferior effect of leaf extracts compared to stem barks, less flavonoid and phenolic content extracted by the methanol solvent compared to ethanol solvent, and improper storage of the leaf extract. Further research on P. guajava was recommended to investigate its mechanism of action, medical interactions, and pharmacokinetic profile. Moreover, an alternative method was recommended, such as the well-diffusion method.

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