Coumarin radical scavenging activity

Citrus sinensis (L.) Osbeck - laranjeira, laranja Tranquilizer Leaf (infusion or decoction, ingested) Caboclos [57,59] Quilombolas [54] Flavonoids [206,207] essential oils [208,209] phenolic compounds Coumarins, fatty acids [210,201] quinoline alkaloids [211,212] Radical scavenging activity [276] antioxidant activity [277] inotropic effect [278]... 

The antioxidants or quenchers of free radicals are known to minimize skin photoaging and the protective action of sun screens correlates closely to their free radical scavenging activity [49,50]. This prompted us to use the prevention of photodynamic yeast cell damage to comparatively investigate the protective activity of the four hydroxycoumarins esculin, esculetin, fraxin and fraxetin, and a widely used sun screen p-aminobenzoic acid (PABA). We applied the same test to characterize the protective activity of four Fraxinus ornus bark preparations containing these coumarins in different concentrations and to examine the activity of caffeic acid (16), a minor constituent of these preparations [51]. 

Rehakova, Z., V. Koleckar, F. Cervenka, L. Jahodar, L. Saso, L. Opletal, D. Jun, and K. Kuca. 2008. DPPH radical scavenging activity of several naturally occurring coumarins and their synthesized analogs measured by the SIA method. Toxicology Mechanisms and Methods 18(5) 413-418. 

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