Antimicrobial activity of Guava tree (Psidium Guajava) leaf extract and selected Commercial Antibiotics on Bacterial isolates from Kisubi Hospital

Abstract

Background: Plant species such as the guava have been used in Uganda and elsewhere in the world to treat some of the medical conditions associated with bacteria, this is due to the increased number of drug resistant bacteria in the world. In this study, the antimicrobial activity of guava leaf extracts against some of the disease causing bacteria isolated from Kisubi hospital in Uganda is discussed. Methods: The guava leafs were collected from a plantation near Zika forest in Uganda (0°7′27″N 32°31′32″E / 0.12417°N 32.52556°E / 0.12417; 32.52556) and samples were put in a bag and transferred to the university laboratory where they were identified. The extracts were obtained by maceration using distilled water, 30%, 50% and 70 % methanol as the extraction solvents. Antimicrobial susceptibility testing was conducted using the disc diffusion method. Results: Gram-negative Escherichia coli was sensitive to the plant extract and synthetic commercial drugs such as trimethoprim-sulfamethozole, ciprofloxacin, and Gentamicin. Pseudomonas aeruginosa was resistant to all drugs. Streptococcus pneumonia and Staphylococcus aureus were all sensitive to the plant extracts with measurable inhibition zones. Conclusion: The Guava tree leaf crude extracts have antimicrobial activity against drug-resistant bacteria. More studies should be carried out to know the potency and the concentration of different plant origin extracts.