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In vitro antimicrobial activity of methanolic leaf extract of Psidium guajava L
Anju Dhiman1, Arun Nanda, Sayeed Ahmad
1Department of Pharmaceutical Sciences, M.D. University, Rohtak, Haryana, India.
Aim:
This study was designed to examine the chemical composition and in vitro antimicrobial potential of methanolic extract of Psidium guajava Linn (Myrtaceae).
Materials And Methods:
The inhibitory effect of methanolic extract of P. guajava was tested against three bacterial and two fungal strains by using the paper disc diffusion method.
Results:
The methanolic extract exhibited antibacterial activity against E. coli with minimum inhibitory concentration, 0.78 μg/ml, minimum bactericidal concentration of 50 μg/ml, and appreciable antifungal activity with minimum inhibitory concentration of 12.5 μg/ml. Preliminary phytochemical analysis of methanolic extract revealed the presence of antimicrobial compounds such as flavonoids, steroids, and tannins, which may contribute for the antimicrobial action of P. guajava.
Conclusion:
The extract was found to be bacteriostatic and fungistatic in action.
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