Low Level of Allergens in the Argentinean Plant Zuccagnia punctata Cav.: Screening and Quality Control of North-Western Propolis Using an LC-DAD-QTOF System

Abstract

North-western Argentinean propolis (NAP), having promising bioactivity, was recently included into the National Food Code. Zuccagnia punctata Cav., a native shrub of north-western Argentina, is one of the prevalent botanical sources of NAPs, but no information on its allergenic constituents was available so far. A liquid chromatography-diode array detector -quadrupole-time of flight system (LC-DAD-QTOF) was used as a screening method for the reliable identification of sensitizing agents belonging to caffeic acid derivatives in Z. punctata and in two NAPs collected in the provinces of Catamarca and Tucumán. Caffeic acid phenethyl ester, one of the most active allergens in propolis, was never detected in either Z. punctata or NAP. Among 31 sensitizers, only geranyl caffeate was alleged in Z. punctata as <10% of its major constituent, whereas three caffeic acid derivatives with strong allergenic effect, i.e., geranyl, pentenyl, and benzyl caffeates, occurred in NAP samples (29%–36% of the Z. punctata major constituent), indicating other minor botanical sources. However, the high content of chalcones and flavonoids ascribed to Z. punctata significantly contributes to the antiallergenic and antioxidant character of these NAPs. This peculiar chemical profile depends on the extremophile condition in which this shrub grows and suggests other studies to characterize such raw materials for oral and topical formulations.