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.
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.