A novel screening method for ingredients of essential oil to identify antibacterial compounds based on growth curve shape

Abstract

We established a novel screening method to identify antibacterial compounds and used the method to screen various triterpenoids, which are difficult to assay using existing methods. The method involves comparison of the shape of bacterial growth curves based on changes in culture turbidity. Growth curves were grouped using multiple classification analysis. The antibacterial compounds tested belonged to a different chemical group than the controls. Six and four of the triterpenoids screened using the method suppressed the growth of Staphylococcus aureus FDA209P and Escherichia coli. W3110, respectively. Two triterpenoids exhibited bactericidal activity against S. aureus, and the others exhibited bacteriostatic activity.