Development of a qPCR assay for the detection of heat-resistant Talaromyces flavus.

Heat-resistant fungi of the species Talaromyces flavus, which inhabits soil and can contaminate fruits, constitutes significant impact on spoilage of heat-processed food. T. flavus possess the ability to produce numerous mycotoxins and is able to survive the process of pasteurization what makes it a treat to food industry. Up to date there is no rapid and reliable method to detect and identify T. flavus. Therefore in this study, a sensitive method for detecting T. flavus was developed. The primers (Tf1_F/R) specific to detection of DNA replication licensing factor gene of T. flavus were designed. With this set of primers, a qPCR reaction with SybrGreen detection was developed. The specificity of assay with use of 5 T. flavus strains and 35 other fungal isolates was tested. The detection threshold was 200 fg of T. flavus genomic DNA. The developed method was able to detect 640 ascospores in 1 g of strawberry fruits and soil samples.