Discrimination of the main Ochratoxin A-producing species in Aspergillus section Circumdati by specific PCR assays

• Published in: International journal of food microbiology 2009-11, Vol.136 (1), p.83-87
• Main Authors: GIL-SERNA, Jéssica, VAZQUEZ, Covadonga, SARDINAS, Noelia, GONZALEZ-JAEN, Ma Teresa, PATINO, Belén
• Format: Article
• Language: English
• Subjects: A. ochraceus; A. steynii; A. westerdijkiae; Aspergillus - classification; Aspergillus - genetics; Aspergillus alutaceus; Aspergillus ochraceus; Aspergillus steynii; Aspergillus westerdijkiae; Biological and medical sciences; Culture collections; DNA, Fungal - analysis; DNA, Fungal - genetics; DNA, Ribosomal Spacer - analysis; DNA, Ribosomal Spacer - genetics; Food industries; Food microbiology; Fundamental and applied biological sciences. Psychology; General aspects; internal transcribed spacers; Methods of analysis, processing and quality control, regulation, standards; microbial genetics; molecular sequence data; molecular systematics; Mycological Typing Techniques - methods; ochratoxin A; Ochratoxins; OTA; PCR detection; Polymerase Chain Reaction; ribosomal DNA; Sensitivity and Specificity; Species Specificity; strain differences; taxonomic revisions; toxigenic strains; Tubulin - genetics
• ISSN: 0168-1605; 1879-3460
• DOI: 10.1016/j.ijfoodmicro.2009.09.018

Ochratoxin A (OTA) is one of the most important mycotoxins because of its high toxicity to both humans and animals and its occurrence in a number of basic foods and agro-products. Some of the main OTA-producing species belong to Aspergillus section Circumdati, whose taxonomy has been lately revised with the description of new species. The high morphological similarity of these species ( A spergillus ochraceus, A spergillus steynii and A spergillus westerdijkiae) makes difficult discrimination among them and with respect to the other species included in the same section unable to produce OTA. In this work, PCR assays specific for the OTA-producing species, A. ochraceus, A. steynii and A. westerdijkiae, were developed on the basis of the multicopy ITS regions of the rDNA. The assays were tested in a wide sample of isolates from diverse origins and culture collections, confirming their specificity, and revealing that the current identification of strains from section Circumdati might need a revision.