Mycotoxigenic moulds and mycotoxins in flours consumed in Turkey.

BACKGROUND: Aflatoxins (AFs) and ochratoxin A (OTA) are metabolites produced by several fungi of the genera Aspergillus and Penicillium and have been found to contaminate human foods and animal feeds. The aim of this study was to investigate the abundance and diversity of total microfungi and mycotoxigenic fungi in 25 samples of different grain-based flours from four regions of Turkey (Thrace and Central, Northwest and West Anatolia) and to evaluate the level of AF and OTA contamination. Microscopic and polymerase chain reaction analyses were used to identify fungi, while high-performance liquid chromatography was used for the detection of AFs and OTA. RESULTS: A total of 551 fungal strains were obtained from the samples and identified morphologically and by multi-locus gene sequencing. All samples were contaminated with fungi ((2-4.8) × 10(4) colony-forming units g(-1) ) and three of them exceeded the European Commission (EC) limits. The data also revealed that 70.5 and 14.7% of the fungal isolates were positive for AF and OTA production respectively. In addition, 21 samples were contaminated by AFs (14.98 and 22.4 µg kg(-1) for AFB1 ) and OTA (3.02 and 4.76 µg kg(-1) ) and three of them exceeded the EC limits. CONCLUSION: This study is the first report on problems with the occurrence of microfungi, mycotoxin contamination, AFs and OTA in different grain-based flour samples from Turkey and highlights developable points of current limits for food and public health safety.

Polymerase chain reaction (PCR) identification of terverticillate Penicillium species isolated from agricultural soils in eskişehir province

In the present study, nine terverticillate Penicillium isolates (P. griseofulfum, P. puberulum, P. crustosum, P. aurantiogriseum, P. chrysogenum, P. primulinum, P. expansum, P. viridicatum, Eupenicillium egyptiacum) from 56 soil samples were characterized genetically by a PCR method. The DNAs of the strains were isolated using the glass beads and vortexing extraction method and then used for PCR amplification with the internal transcribed spacer 1 (ITS1) and ITS4 universal fungal specific primers. The ITS regions of fungal ribosomal DNA (rDNA) were sequenced through the CEQ 8000 Genetic Analysis System. ITS-5.8S sequences obtained were compared with those deposited in the GenBank Database. The results indicated that the identification of Penicillium species with PCR based methods provided significant information about the solution to taxonomy and improve food safety and to protect the users from harmful contaminants such as mycotoxins, which must be controlled during the production of agricultural materials as well as during the processing of food and feed.