Epr fingerprinting and antioxidant response of four selected plantago species

Abstract

In this study we compare the phytochemical composition and antioxidant properties of four Plantago species (P. cornuti, P. lanceolata, P. major and P. media), in terms of radical scavenging ability and their reductive properties in corroboration with EPR spectroscopy profiling. We found that Plantago extracts possess very low prooxidant activity while being efficient radical scavengers and electron donors. P. media showed the strongest antioxidant activity from the four species investigated. The relative composition derived from the EPR spectra of the studied extracts was compared to the phytochemical composition determined by HPLC-MS analysis. Downhill Simplex algorithm simulation of EPR experimental signals revealed that all four Plantago extracts display luteolin and chlorogenic acid profiles, as well as quercetin glycosides, especially rutin. EPR spectroscopy appears to be a useful tool for discrimination of radical-based complex mixture, rendering it as an alternative method for predicting chemical behaviour, regardless of synergistic or antagonistic effects.