Antibacterial activity of avocado extract (Persea americana Mill.) against aminoglycoside-resistant Klebsiella pneumoniae strains

Klebsiella pneumoniae is an important etiological agent of nosocomial infections. This study focuses on the antibacterial activity of Persea Americana extract against K. pneumoniae strains containing aminoglycoside genes. Broth microdilution technique was used to examine the antibacterial activity of P. americana extract on K. pneumoniae isolates. The phenolic components of its leaves were analysed by the HPLC-DAD system. The binding potential of the major phytochemical component of the extract, chlorogenic acid, to the KsgA was investigated by molecular docking. The stability of the resulting enzyme-ligand complexes was also assessed through molecular dynamics simulation. The result obtained showed that P. americana extract had antibacterial activity on aminoglycoside resistant strains. The binding potential of chlorogenic acid (main phenolic compound) to KsgA was found to be higher than the binding of gentamicin. Since chlorogenic acid had lower binding energy and formed higher number of H-bonding as well as other interactions in the docking analysis. The higher binding potential of the major component with the enzyme that was involved in resistance development against aminoglycoside indicated its possible role in overturning the condition. Moreover, the molecular dynamics simulation study revealed that chlorogenic acid formed a complex with relatively higher stability. The higher binding potential of the major component with higher stability implied that the computational results confirmed the experimental findings.