title: Low-density lipoprotein (LDL)-antioxidant biflavonoids from Garcinia madruno.
abstract: Six biflavonoids were isolated from G. madruno, one of which, 7''-O-(6''''-acetyl)-glucoside of morelloflavone, is a new compound identified on the basis of 1D, 2D NMR (HMQC and HMBC) spectroscopic methods and chemical evidence. The antioxidant activity of the biflavonoids against low-density lipoprotein (LDL) peroxidation induced with Cu²⁺, was studied by means of a TBARS assay. The antioxidant potential of a biflavonoid fraction (BF) was also evaluated and correlated with its biflavonoid content. The flavanone-(3→8'')-flavone biflavonoids displayed antioxidant activity, particularly morelloflavone, which was significantly more potent than quercetin, with a CE₅₀ of 12.36 μg/mL. Lipid peroxidation, was also significantly reduced in the presence of the BF (EC₅₀ = 11.85 μg/mL). These results suggest that the BF is an excellent antioxidant.
authors.affiliation: Grupo de Investigación en Sustancias Bioactivas, Facultad de Química Farmacéutica, Universidad de Antioquia, Carrera 53 n 61-30., A.A. 1226, Medellín, Colombia. josorio@farmacia.udea.edu.co
authors.forename: Edison
authors.initials: E
authors.lastname: Osorio
authors.forename: Julián
authors.initials: J
authors.lastname: Londoño
authors.forename: Jaume
authors.initials: J
authors.lastname: Bastida
mesh_terms: D000328:Adult; D000975:Antioxidants / Q000737:chemistry* / Q000302:isolation & purification*; D044946:Biflavonoids; D003300:Copper / Q000737:chemistry; D005260:Female; D029760:Garcinia / Q000737:chemistry*; D006801:Humans; D015227:Lipid Peroxidation; D008077:Lipoproteins, LDL / Q000737:chemistry*; D008297:Male
chemical_list: D000975:Antioxidants; D044946:Biflavonoids; D008077:Lipoproteins, LDL; D003300:Copper