title: Effect of pH on ochratoxin A production by Aspergillus niger aggregate species.
abstract: The effect of pH (2-10) on growth and ochratoxin A (OTA) production by 12 Aspergillus niger aggregate strains was studied in two culture media: Czapek yeast autolysate agar (CYA) and yeast extract sucrose agar (YES), over 30 days. The strains were selected to include different sources, different reported abilities to produce OTA and different ITS-5.8S rDNA RFLP patterns. YES was a better culture medium than CYA for OTA production. In this medium, OTA was produced from pH 2 or 3 to 10 depending on the strain. The results show the ability of A. niger aggregate strains not only to grow, but also to produce OTA over a wide pH range. The results will lead to a better understanding of the role of A. niger aggregate strains in the OTA contamination of several food commodities.
authors.affiliation: Grup de Micologia Veterinària, Departament de Sanitat i d'Anatomia Animals, Facultat de Veterinària, Universitat Autònoma de Barcelona, E-08193 Bellaterra, Barcelona, Spain.
authors.forename: A
authors.initials: A
authors.lastname: Esteban
authors.forename: M L
authors.initials: ML
authors.lastname: Abarca
authors.forename: M R
authors.initials: MR
authors.lastname: Bragulat
authors.forename: F J
authors.initials: FJ
authors.lastname: Cabañes
mesh_terms: D001234:Aspergillus niger / Q000502:physiology*; D003470:Culture Media; D004271:DNA, Fungal / Q000235:genetics; D021903:DNA, Ribosomal Spacer / Q000235:genetics; D005506:Food Contamination; D005516:Food Microbiology; D006863:Hydrogen-Ion Concentration; D009183:Mycotoxins / Q000032:analysis / Q000096:biosynthesis*; D009793:Ochratoxins / Q000032:analysis / Q000096:biosynthesis*; D012150:Polymorphism, Restriction Fragment Length; D013395:Sucrose / Q000378:metabolism; D015003:Yeasts / Q000378:metabolism
chemical_list: D003470:Culture Media; D004271:DNA, Fungal; D021903:DNA, Ribosomal Spacer; D009183:Mycotoxins; D009793:Ochratoxins; C025589:ochratoxin A; D013395:Sucrose