Protective effect against oxygen reactive species and skin fibroblast stimulation of Couroupita guianensis leaf extracts

Abstract

In this study, hydroalcoholic leaf extracts of Couroupita guianensis were examined for antioxidant activity, phytochemical and total phenolic composition, stimulation of human skin fibroblast (HSF) proliferation and UV-absorption. The radical scavenging capacity, reducing power and protection against joint oxidation of linoleic acid and β-carotene bleaching oxidation in emulsion were used to evaluate the antioxidant activity. The results of this study strongly indicate in vitro antioxidant activity, which may be due to the presence of a high total phenolic content. In order to identify active principles, the extracts were submitted to fractionation and the compounds isolated were the flavonoids 2′,4′-dihydroxy-6′-methoxy-3′,5′-dimethylchalcone (1), 7-hydroxy-5-methoxy-6,8-dimethylflavanone (2) and the phenolic acid 4-hydroxybenzoic acid (3). In addition, a high level of stimulation of HSF proliferation and significant absorption of UV radiation were also observed. The results suggest that the hydroalcoholic leaf extracts of C. guianensis have promising skin care properties.

Keywords:

• Couroupita guianensis
• antioxidant
• phenolics
• fibroblast
• UV-absorption

Acknowledgements

The authors thank CarOi'Line Cosmética for its support for this work. They also thank Rein Blinker and Tropilab Inc. for supplying their plant for this study. Measurements were performed at the Unidade de Raios X, Servizo de Espectrometría de Masas and Servizo de Resonancia Magnética at RIAIDT.