Background: Psidium guajava is a tropical plant of family myrtaceae. Guava leaves have photochemical constituents; tannins, carotenoids, polyphenol, flavonoids. The leaves have pharmacological activities which are antibacterial, anticancer, anti-inflammatory, analgesics. Methicillin resistant staphylococcus aureus (MRSA) is multidrug resistant strain, against penicillin group of antibiotics. Surgical site infection is a common problem in our setting with common causative agents being is staphylococcus aureus of which 18.8% of reported in MRSA.
Methodology: this experimental study was conducted at CUHAS Multipurpose laboratory. Antibacterial activity of psidium guajava was studied using 20 retrievable isolates of MRSA. Different concentration of extract was prepared using ethanol as a solvent. Blood agar was used for subculture and Muller Hinton agar was used as a base for agar dilution susceptibility method.
Results and discussion: in this study it was found that guava have antibacterial activities against MRSA with a minimum inhibitory concentration (MIC) of 10 mg/ml in contrast with the study done in Nigeria where the MIC was 500ug/ml. the different in (MIC) in this two study may be brought about by different in solvent used. Sensitive staphylococcus aureus SSA was used as a control and it was inhibited at lower concentration of 5gm/ml in which for MRSA is unable to limit.
Conclusion and recommendation: Guava as antibacterial activities against MRSA with a MIC of 10mg/ml. I recommend further study to be done on phytochemical constituent in guava leaves and its antibacterial activities against other resistant strain of bacteria.