In vitro evaluation of antibacterial potential of Stevia rebaudiana Bertoni against various bacterial pathogens including resistant isolates with bla genes

Alcoholic leaf extract of Stevia rebaudiana was analyzed for in vitro antibacterial potential against various pathogenic bacteria including resistant isolates harbouring bla genes using agar well diffusion method. It effectively controlled the growth of most of the tested gram positive bacteria and moderately controlled the growth of tested gram negative bacterial species. It also effectively controlled the growth of resistant bacteria containing bla genes. Minimum inhibitory concentrations (MIC) of the alcoholic extract were determined by broth microdilution method. MIC against gram positive bacteria ranged from 1.53 to 6.10 μg/ml, while MIC against gram negative bacteria ranged from 3.05 to 12.0 μg/ml and MIC against resistant bacteria harbouring bla genes ranged from 24.0 to 98.0 μg/ml. This is the first report of antibacterial activity of S. rebaudiana against resistant gram negative bacteria harbouring bla genes.