Sensitivity of extended-spectrum β-lactamases producing Enterobacteriaceae isolates to Annona squamosa extracts

Abstract

Powdered leaves of Annona squamosa (L.) were extracted with ethanol and methanol using percolation method. The extracts were tested for antimicrobial activity against clinical isolates of confirmed extended spectrum β-lactamase producing Escherichia coli, Klebsiella pneumoniae and Proteus specie using disc diffusion method. The extracts were further subjected to phytochemical screening for the presence of secondary metabolites. Sensitivity test results showed that methanol extract of the plant was only active on E. coli at 30 μg/disc concentration with 7mm zone of inhibition but inactive against P. specie even at 60 μg/disc concentration. Ethanol extract of the plant was active against all isolates only at 60 μg/disc concentration with P. specie forming slightly wider zone of inhibition (8mm) and the remaining isolates having 7mm zone diameter. The results of phytochemical screening indicated the presence of reducing sugars, saponins and steroids in either or both extracts.

Keywords: Sensitivity, ESBLs, Enterobacteriaceae, Annona squamosa, Extracts