Title |
Impact of Some Environmental Factors on Growth and Production of Ochratoxin A of/by Aspergillus tubingensis, A. niger, and A. carbonarius Isolated from Moroccan Grapes |
Author |
Atar Selouane1, Driss Bouya1, Ahmed Lebrihi2, C. Decock3, and Amina Bouseta1* |
Address |
1Laboratoire d’Agroalimentaire et Sécurité Sanitaire des Aliments, UFR de Biochimie Appliquée et Sciences Alimentaires & UFR de Protection des plantes et environnement, Université Sidi Mohamed Ben Abdellah, Faculté des Sciences Dhar El Mahraz, B.P. 1796 Atlas Fès 30000, Morocco, 2Laboratoire de Génie Chimique UMR 5503 (CNRS-INPT-UPS), Ecole Nationale Supérieure Agronomique de Toulouse (ENSAT), 1, Avenue de l’Agrobiopôle, Auzeville-Tolosane, France , 3Mycothèque de l’Université catholique de Louvain (MUCL), Faculté d’Ingénierie Biologique, Agronomique et Environnementale, UCL, Louvain-La-Neuve, Belgium |
Bibliography |
Journal of Microbiology, 47(4),411-419, 2009,
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DOI |
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Key Words |
Aspergillus tubingensis, A. niger, A. carbonarius, ochratoxin A, temperature, water activity |
Abstract |
The effects of temperature, water activity (aw), incubation time, and their combinations on radial growth and ochratoxin A (OTA) production of/by eight Aspergillus niger aggregate strains (six A. tubingensis and two A. niger) and four A. carbonarius isolated from Moroccan grapes were studied. Optimal conditions for the growth of most studied strains were shown to be at 25°C and 0.95 aw. No growth was observed at 10°C regardless of the water activity and isolates. The optimal temperature for OTA production was in the range of 25°C~30°C for A. carbonarius and 30°C~37°C for A. niger aggregate. The optimal aw for toxin production was 0.95~0.99 for A. carbonarius and 0.90~0.95 for A. niger aggregate. Mean OTA concentration produced by all the isolates of A. niger aggregate tested at all sampling times shows that maximum amount of OTA (0.24 µg/g) was produced at 37°C and 0.90 aw. However, for A. carbonarius, mean maximum amounts of OTA (0.22 µg/g) were observed at 25°C and 0.99 aw. Analysis of variance showed that the effects of all single factors (aw, isolate, temperature and incubation time) and their interactions on growth and OTA production were highly significant. |