Antibacterial Activity of <i>Psidium guajava</i> Leaf Extract against Selected Pathogenic Bacteria

Abstract

This study has been embarked upon due to increased resistance of bacteria to many already synthesized drugs and the high price of the orthodox medicines in the market, the antimicrobial effect of Psidium guajava leaf extracts against selected drug-resistant bacteria will help to reduce the overdependence on orthodox or synthetic drugs which greater population of the society cannot afford due to economic/financial restriction. Ethanolic and aqueous extracts of Psidium guajava were assayed for antibacterial activity using the agar dilution method in the determination of the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC). The bioactive components of the extracts were determined using standard techniques and the inhibitory activities of the extracts were compared to gentamicin, ciprofloxacin, erythromycin, azithromycin, ofloxacin, and nitrofurantoin. The MIC of the extract on the test organisms ranges from 10 mg/ml - 40 mg/ml. The sensitivity test showed that the organisms were susceptible to Psidium guajava leave extract except Pseudomonas aeruginosa . The phytochemical analysis of the extracts revealed the presence of bioactive compounds such as Tannin, Saponin, Balsam, Flavonoids, Alkaloids, Cardiac glycosides, Carbohydrate, Resins, Terpenes, and Sterols. It has been shown that the leaves of Psidium guajava have antibacterial effects and hence can be used to treat the ailments caused by those organisms at a particular dosage and concentration. However, more research work on its toxicity level, synergistic or antagonistic interaction with other plants or drugs is needed to consolidate its usage.