Comparative growth curve analysis of E. coli and S. aureus in response to Ninhydrin exposure

Ninhydrin, a principal agent used in amino acid identification, has hardly been studied for its antimicrobial properties. The present study investigated its effects on the growth of Escherichia coli and Staphylococcus aureus, two model bacterial pathogens. The cultures of E. coli and S. aureus were grown in nutrient broth supplemented with ninhydrin at concentrations of 0.25%, 1% and 2%. Growth was quantified by the colony count on solid media plates and the curve analysis was performed. Both organisms showed a decline phase in growth in comparison to control cultures. All the concentrations taken into consideration exhibited the most growth inhibition, with a significant reduction in OD readings noticeable in both strains. Thus, ninhydrin has shown excellent activity against Escherichia coli and Staphylococcus aureus.