Antimicrobial Activity of Psidium Guajava (Guava) Leaves Extract on Extended-Spectrum Beta-Lactamase-Producing Klebsiella Pneumoniae that Cause Multi-Drug Resistant Urinary Tract Infections

Extended-spectrum beta-lactamases (ESBLs) are plasmid-mediated enzymes commonly found in the Enterobacteriaceae that are capable of hydrolysing ß-lactams except carbapenems and cephamycins. ESBLs also confer resistance to several non-ß-lactam antibiotics. ESBL producing isolates are predominantly Klebsiella pneumoniae and Eschericia coli. Klebsiella pneumoniae are one of the most common causes of urinary tract infections such as cystitis and pyelonephritis developed by about 150 million people in every given year. ESBL-producing Klebsiella pneumoniae appear susceptible to cephalosporins in vitro using conventional breakpoints but ineffective in vivo. This has limited treatment options for urinary tract infections caused by extended-spectrum beta-lactamases -producing K. pneumoniae. This study determined the in vitro efficacy of Psidium guajava on extended-spectrum beta-lactamases -producing K. pneumoniae using agar well diffusion and well microplate dilution method. Serial dilutions of the ethanolic extract of the leaves were prepared and tested against the extended-spectrum beta-lactamases-producing K. pneumoniae. The phytochemical screening was performed to determine the antibacterial compounds. The guava leaves extracts concentrations ranging from 50 mg/ml – 200 mg/ml showed active diameter zone of inhibition. The ethanolic extract of guava leaves had minimum inhibition concentration and minimum bactericidal concentration of 6.25mg/ml indicating significant antibiotic activity against the ESBL isolates. The phytochemical screening of the guava leaves showed the presence of antimicrobial phytochemicals such as flavonoids. Ethanolic extracts of guava leaves is proving to be efficacious against multi-drug resistant ESBL-producing K. pneumoniae, which a major cause urinary tract infections. This offers hope for the development of effective antibiotics against multi-drug resistant urinary tract infections due to the presence of flavonoids in the guava leaf extracts. Therefore, there is the need to determine the toxicological effect of the active antimicrobial compounds isolated in the leaf extracts of guava plant. Keywords: Psidium guajava, Flavonoids, Multi-drug resistant, Extended-spectrum beta-lactamase, Klebsiella pneumoniae DOI: 10.7176/JNSR/11-22-02 Publication date: November 30th 202