Psidium guajava L. commonly known as Guava, is a medicinal plant belonging to the family Myrtaceae. P. guajava is a well known traditional medicinal plant used in various indigenous systems of medicine. It is widely distributed throughout India. The present study provides phytochemical and antimicrobial details of the methanolic leaf extract of P. guajava against clinically important gastrointestinal pathogens viz. Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli, Salmonella typhi, Vibrio cholerae. The phytochemical analysis carried out revealed the presence of flavanoids, glycosides, alkaloids and steroids and many other metabolites and absence of tannins and saponins. Minimum inhibitory concentration (MIC) assay was determined for the extract. The methanolic extract showed toxicity against all the bacteria, S.typhi being highly susceptible with a zone of inhibition of 2mm at 4mg/ml. Thus Psidium guajava leaf extract has a potential of providing safe and cheap drugs and drug leads for human use.
