Amo De Paz, GuillermoRaggio Quílez, JoséGómez-Serranillos Cuadrado, María PilarPalomino Ruiz-Poveda, Olga MaríaGonzález Burgos, Elena MaríaCarretero Accame, María EmiliaCrespo De Las Casas, Ana María2024-01-122024-01-122010-04-24Amo de Paz, G.; Raggio, J.; Gómez-Serranillos, M.P.; Palomino, O.M.; González-Burgos, E.; Carretero, M.E.; Crespo, A. HPLC isolation of antioxidant constituents from Xanthoparmelia spp. J. Pharm. Biomed. Anal. 2010, 53, 165–1710731-708510.1016/j.jpba.2010.04.013https://hdl.handle.net/20.500.14352/92680A chromatographic method is described for the purification and characterization of secondary lichen substances with biological activity. A simple reversed-phase high-performance liquid chromatography method with gradient elution has been developed that allows the determination and isolation of salazinic, usnic and stictic acids from lichen samples in a single run and the quantification of every acid in the tested extracts. The antioxidant activity of both the isolated compounds and the respective lichen belonging to Xanthoparmelia genus was determined by the Oxygen Radical Absorbance Capacity (ORAC) assay; their effect as free radical scavengers, effect on cell survival by the 3(4,5-dimethyltiazol-2-yl)-2,5-diphenyltetrazolium reduction assay and 2′,7′-dichlorofluorescin diacetate method were tested on U373 MG human astrocytome cell line. Both lichens extracts and all isolated compounds protected U373 MG cells from hydrogen peroxide-induced damage, suggesting that they could act as antioxidant agents in those neurodegenerative disorders associated with oxidative damage, such as Alzheimer's disease and Parkinson's disease.engjournal article1873-264Xhttps://doi.org/10.1016/j.jpba.2010.04.013restricted access664.022615.212HPLCsalazinic acidusnic acidstictic acidantioxidantastrocyteFarmacología (Farmacia)Fisiología vegetal (Biología)2417.19 Fisiología Vegetal3209.05 Farmacognosia