Scientific validation of synergistic antioxidant effects in commercialised mixtures of Cymbopogon citratus and Pterospartum tridentatum or Gomphrena globosa for infusions preparation

Pterospartum tridentatum (L.) Willk., Gomphrena globosa L. and Cymbopogon citratus (DC) Stapf. are examples of medicinal plants with antioxidant properties on their own, but that can be improved when mixed. In the present work, the antioxidant activity and phenolic compounds were determined in the infusions prepared from the individual plants, and from mixtures of these plants in different proportions. P. tridentatum > C. citratus > G. globosa was the order observed for antioxidant efficacy, which can be related to their different composition in phenolic compounds. Synergism was the main effect observed among the tested mixtures, mainly for the infusions prepared from the plants in proportion 40%:60% (either P. tridentatum and C. citratus; or G. globosa and C. citratus). The infusion obtained with 40% of P. tridentatum and 60% of C. citratus gave the highest antioxidant properties. The present study validates the commercialisation of the studied plants combined in specific proportions.