title: Differentiation between Aspergillus flavus and Aspergillus parasiticus from pure culture and aflatoxin-contaminated grapes using PCR-RFLP analysis of aflR-aflJ intergenic spacer.
abstract: Aflatoxins (AFs) represent the most important single mycotoxin-related food safety problem in developed and developing countries as they have adverse effects on human and animal health. They are produced mainly by Aspergillus flavus and A. parasiticus. Both species have different aflatoxinogenic profile. In order to distinguish between A. flavus and A. parasiticus, gene-specific primers were designed to target the intergenic spacer (IGS) for the AF biosynthesis genes, aflJ and aflR. Polymerase chain reaction (PCR) products were subjected to restriction endonuclease analysis using BglII to look for restriction fragment length polymorphisms (RFLPs). Our result showed that both species displayed different PCR-based RFLP (PCR-RFLP) profile. PCR products from A. flavus cleaved into 3 fragments of 362, 210, and 102 bp. However, there is only one restriction site for this enzyme in the sequence of A. parasiticus that produced only 2 fragments of 363 and 311 bp. The method was successfully applied to contaminated grapes samples. This approach of differentiating these 2 species would be simpler, less costly, and quicker than conventional sequencing of PCR products and/or morphological identification.
authors.affiliation: Centre d'analyses et de recherches, Faculté des Sciences, Univ. Saint-Joseph, Beyrouth, Liban. eandre@fs.usj.edu.lb
authors.forename: André
authors.initials: A
authors.lastname: El Khoury
authors.forename: Ali
authors.initials: A
authors.lastname: Atoui
authors.forename: Toufic
authors.initials: T
authors.lastname: Rizk
authors.forename: Roger
authors.initials: R
authors.lastname: Lteif
authors.forename: Mireille
authors.initials: M
authors.lastname: Kallassy
authors.forename: Ahmed
authors.initials: A
authors.lastname: Lebrihi
mesh_terms: D000348:Aflatoxins / Q000302:isolation & purification*; D001230:Aspergillus / Q000145:classification / Q000302:isolation & purification*; D001231:Aspergillus flavus / Q000145:classification / Q000302:isolation & purification*; D017931:DNA Primers; D004271:DNA, Fungal / Q000235:genetics / Q000302:isolation & purification; D021903:DNA, Ribosomal Spacer / Q000235:genetics / Q000302:isolation & purification; D004268:DNA-Binding Proteins / Q000235:genetics; D005506:Food Contamination / Q000032:analysis*; D005516:Food Microbiology / Q000379:methods; D005656:Fungal Proteins / Q000235:genetics; D016133:Polymerase Chain Reaction / Q000379:methods; D012150:Polymorphism, Restriction Fragment Length; D014157:Transcription Factors / Q000235:genetics; D027843:Vitis / Q000382:microbiology*
chemical_list: C113837:AFLR protein, Aspergillus; D000348:Aflatoxins; D017931:DNA Primers; D004271:DNA, Fungal; D021903:DNA, Ribosomal Spacer; D004268:DNA-Binding Proteins; D005656:Fungal Proteins; D014157:Transcription Factors