Thujaplicins from Thuja plicata as iron transport agents for Salmonella typhimurium

Abstract

Strains of Salmonella typhimurium which are unable to synthesize their normal iron transport agent, enterobactin, and which must be supported with an exogenous chelator (siderophore) on certain media, were used to examine various types of wood for the presence of chelators. Western red cedar wood, Thuja plicata, was observed to contain large amounts of three substances that in low concentration would serve as chelators for S. typhimurium. The chelators from T. plicata were characterized and found to be alpha-, beta-, and gamma-thujaplicin. Other planar cyclic alpha-hydroxyketones were examined, and several were found to function as chelators for S. typhimurium.