Identification of aspergillus flavus and aspergillus parasiticus by real-time PCR and investigation of the presence of aflatoxin in some nuts collected from sweet sellers in Diyarbakır

1.2.Abstract Aim: In our study; It was aimed to identify Aspergillus flavus and Aspergillus parasiticus, which can cause diseases and various infections, at the molecular level and to investigate the presence of their secondary metabolites, aflatoxin, in nuts, which are widely used and consumed in various sectors all over the world. Materials and Methods: A total of 90 samples of ground nuts including pistachios (n:30), walnuts (n:30) and peanuts (n:30) were collected from sweet shops operating in the central districts of Diyarbakır. Suspected colonies isolated from nuts were identified by cultural method. Confirmed by real-time PCR. Results: The prevalence of Aspergillus flavus in the analysed samples was 34.4% (31/90), 33.3% (10/30) in pistachio samples, 40% (12/30) in walnut samples, 30% (9/30) in peanut samples. 54.4% of all nuts analysed were above the legal limit for AFB1 and 22.2% for TAF. Conclusion: The results show that most of the samples had higher Alatoxin B1 contamination than the legal limit specified in both the national and EU legislation. Mycotoxigenic A. flavus isolates are high contaminants for food. In order to reduce the risk of toxin contamination in nuts, it is necessary to prevent mould contamination and both producers and consumers should pay attention to hygiene rules. Key Words: Aspergillus flavus, Aflatoxin, nuts, Real-time PCR, ELISA