title: A polyphenol-enriched cocoa extract reduces free radicals produced by mycotoxins.
abstract: Polyphenols are characterized by the presence of phenol units in the molecules. These compounds may show antioxidant ability by scavenging reactive oxygen species (ROS) of the free radical type. A polyphenol enriched cocoa extract (PECE) was obtained from cocoa seeds with 28% of procyanidins which were mainly epicatechin oligomers. PECE was very active as free radical scavenger against 2,2'-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid (ABTS), 1,1-diphenyl-2-picrylhydrazyl radical (DPPH) and tris(2,4,6-trichloro-3,5-dinitrophenyl)methyl (HNTTM) radicals; and the tris(2,3,5,6-tetrachloro-4-nitrophenyl)methyl (TNPTM) assay showed that the PECE might not be pro-oxidant. Thus it was considered a good candidate to be tested in in vitro models. It showed mild cytotoxic power on Hep G2 cells and induced ROS in a dose-dependent manner being weak oxidant only at high concentrations near the limit of solubility. The antioxidant properties were assayed in Hep G2 treated with the mycotoxins ochratoxin A (OTA) and/or aflatoxin B1 (AFB1). The PECE was not effective against AFB1 but it increased the cell viability and reduced significantly the amounts of ROS in cells treated with OTA or mixtures of AFB1+OTA. These results are coherent with the role of oxidative pathways in the mechanism of OTA and indicate that polyphenols extracted from cocoa may be good candidates as antioxidant agents.
authors.affiliation: Department of Nutrition and Food Sciences, Physiology and Toxicology, Faculty of Pharmacy, University of Navarra, Irunlarrea 1, E-31008 Pamplona, Spain. lcorcuer@alumni.unav.es
authors.forename: L A
authors.initials: LA
authors.lastname: Corcuera
authors.forename: S
authors.initials: S
authors.lastname: Amézqueta
authors.forename: L
authors.initials: L
authors.lastname: Arbillaga
authors.forename: A
authors.initials: A
authors.lastname: Vettorazzi
authors.forename: S
authors.initials: S
authors.lastname: Touriño
authors.forename: J L
authors.initials: JL
authors.lastname: Torres
authors.forename: A
authors.initials: A
authors.lastname: López de Cerain
mesh_terms: D002099:Cacao / Q000737:chemistry*; D045744:Cell Line, Tumor; D002474:Cell-Free System; D016166:Free Radical Scavengers / Q000494:pharmacology*; D005609:Free Radicals / Q000378:metabolism; D006801:Humans; D009183:Mycotoxins / Q000494:pharmacology*; D010936:Plant Extracts / Q000494:pharmacology*; D059808:Polyphenols / Q000494:pharmacology*; D017382:Reactive Oxygen Species / Q000378:metabolism; D012995:Solubility
chemical_list: D016166:Free Radical Scavengers; D005609:Free Radicals; D009183:Mycotoxins; D010936:Plant Extracts; D059808:Polyphenols; D017382:Reactive Oxygen Species