title: Effect of oxidant stressors and phenolic antioxidants on the ochratoxigenic fungus Aspergillus carbonarius.
abstract: BACKGROUND
  There are few studies dealing with the relationship between oxidative stress and ochratoxin A (OTA) biosynthesis. In this work, we analyzed the effect of the oxidant stressor menadione and the antioxidants 3,5-di-tert-butyl-4-hydroxytoluene (BHT), catechin, resveratrol and a polyphenolic extract on growth, generation of reactive oxygen species (ROS), OTA production and gene expression of antioxidant enzymes of Aspergillus carbonarius.
  
  
  RESULTS
  Exposure to menadione concentrations higher than 20 µmol L(-1) led to increases in ROS and OTA levels and a decrease in growth rate. Exposure to 2.5-10 mmol L(-1) BHT also led to higher ROS and OTA levels, although growth rate was only affected above 5 mmol L(-1). Naturally occurring concentrations of catechin, resveratrol and polyphenolic extract barely affected growth rate, but they produced widely different effects on OTA production level depending on the antioxidant concentration used. In general, gene expression of antioxidant enzymes superoxide dismutase (SOD) and peroxiredoxin (PRX) was downregulated after exposure to oxidant and antioxidant concentrations that enhanced OTA production level.
  
  
  CONCLUSIONS
  Aspergillus carbonarius responds to oxidative stress, increasing OTA production. Nevertheless, the use of naturally occurring concentrations of antioxidant phenolic compounds to reduce oxidative stress is not a valid approach by itself for OTA contamination control in grapes.
authors: Departamento de Ciencias de los Alimentos, Instituto de Agroquímica y Tecnología de los Alimentos (IATA-CSIC), 46980 Valencia, Spain.|Departamento de Medicina Preventiva y Salud Pública, Ciencias de la Alimentación, Bromatología, Toxicología y Medicina Legal, Universitat de València, 46100 Valencia, Spain.
authors: Ana
authors: A
authors: Crespo-Sempere
authors: Departamento de Ciencias de los Alimentos, Instituto de Agroquímica y Tecnología de los Alimentos (IATA-CSIC), 46980 Valencia, Spain.|Departamento de Medicina Preventiva y Salud Pública, Ciencias de la Alimentación, Bromatología, Toxicología y Medicina Legal, Universitat de València, 46100 Valencia, Spain.
authors: Cristina
authors: C
authors: Selma-Lázaro
authors: Foodborne Toxin Detection and Prevention Research Unit, US Department of Agriculture, Agricultural Research Service, Albany, CA 94710, USA.
authors: Jeffrey D
authors: JD
authors: Palumbo
authors: Departamento de Ciencias de los Alimentos, Instituto de Agroquímica y Tecnología de los Alimentos (IATA-CSIC), 46980 Valencia, Spain.
authors: Luis
authors: L
authors: González-Candelas
authors: Departamento de Ciencias de los Alimentos, Instituto de Agroquímica y Tecnología de los Alimentos (IATA-CSIC), 46980 Valencia, Spain.|Departamento de Medicina Preventiva y Salud Pública, Ciencias de la Alimentación, Bromatología, Toxicología y Medicina Legal, Universitat de València, 46100 Valencia, Spain.
authors: Pedro V
authors: PV
authors: Martínez-Culebras
mesh_terms: D000975:Antioxidants / Q000494:pharmacology*; D001230:Aspergillus / Q000187:drug effects* / Q000254:growth & development / Q000378:metabolism; D002084:Butylated Hydroxytoluene / Q000031:analogs & derivatives / Q000494:pharmacology; D002392:Catechin / Q000494:pharmacology; D005506:Food Contamination / Q000517:prevention & control; D005516:Food Microbiology; D005638:Fruit / Q000737:chemistry*; D006801:Humans; D009793:Ochratoxins / Q000096:biosynthesis*; D016877:Oxidants / Q000494:pharmacology; D018384:Oxidative Stress / Q000187:drug effects*; D054464:Peroxiredoxins / Q000378:metabolism; D010636:Phenols / Q000494:pharmacology*; D010936:Plant Extracts / Q000494:pharmacology; D000077185:Resveratrol; D013267:Stilbenes / Q000494:pharmacology; D013482:Superoxide Dismutase / Q000378:metabolism; D024483:Vitamin K 3 / Q000494:pharmacology; D027843:Vitis / Q000737:chemistry / Q000382:microbiology*; D014920:Wine
chemical_list: D000975:Antioxidants; D009793:Ochratoxins; D016877:Oxidants; D010636:Phenols; D010936:Plant Extracts; D013267:Stilbenes; D002084:Butylated Hydroxytoluene; D024483:Vitamin K 3; D002392:Catechin; C037667:3,5-di-tert-butyl-4-hydroxytoluene; D054464:Peroxiredoxins; D013482:Superoxide Dismutase; D000077185:Resveratrol
keywords: Aspergillus carbonarius; grapes; ochratoxin production; oxidative stress