Effect of oxidant stressors and phenolic antioxidants on the ochratoxigenic fungus Aspergillus carbonarius

• Published in: Journal of the science of food and agriculture 2016-01, Vol.96 (1), p.169-177
• Main Authors: Crespo-Sempere, Ana, Selma-Lázaro, Cristina, Palumbo, Jeffrey D, González-Candelas, Luis, Martínez-Culebras, Pedro V
• Format: Article
• Language: English
• Subjects: Antioxidants; Antioxidants - pharmacology; Aspergillus - drug effects; Aspergillus - growth & development; Aspergillus - metabolism; Aspergillus carbonarius; Biosynthesis; butylated hydroxytoluene; Butylated Hydroxytoluene - analogs & derivatives; Butylated Hydroxytoluene - pharmacology; catechin; Catechin - pharmacology; Enzymes; Exposure; Food Contamination - prevention & control; Food Microbiology; Fruit - chemistry; Fungi; Gene expression; grapes; Humans; menadione; ochratoxin A; ochratoxin production; Ochratoxins - biosynthesis; Oxidants; Oxidants - pharmacology; Oxidative stress; Oxidative Stress - drug effects; Oxidizing agents; peroxiredoxin; Peroxiredoxins - metabolism; Phenols - pharmacology; Plant Extracts - pharmacology; reactive oxygen species; resveratrol; Stilbenes - pharmacology; Stress concentration; Stresses; superoxide dismutase; Superoxide Dismutase - metabolism; toxigenic strains; Vitaceae; Vitamin K 3 - pharmacology; Vitis - chemistry; Vitis - microbiology; Wine
• ISSN: 0022-5142; 1097-0010
• DOI: 10.1002/jsfa.7077

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. CONCLUSION: 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.