Determination of the concentration of potential efflux pump inhibitors, pheophorbide a and pyropheophorbide a, in the feces of animals by fluorescence spectroscopy.

Efflux pumps are vital bacterial components, and research has demonstrated that some plant compounds such as pheophorbide a (php) possess efflux pump inhibitor (EPI) activity. This study determined the quantity of php present in feces as an indicator of EPI activity. Feces were collected from different species of animals fed a variety of feeds.