Detection of Some Hazardous Pathogens Affecting Nutritional and Health Attributes in Fresh Dairy Products

The present study was conducted to examine the quality and safety of dairy products available at local markets in Karbala, Iraq by isolating and characterizing contaminating fungi. Different samples of dairy products such as Yogurt, Cheese, Cream, Fermented milk, and Qaymar were collected from local markets and were cultured in PDA medium. After fungal colonies appeared, they were purified using the hyphal tip technique. Morphological, microscopic and molecular identification of the isolated fungi was done by polymerase chain reaction (PCR). Amplified DNA products were sequenced, and nucleotide sequences were aligned to the nucleotide sequences of the same genetic region of recorded isolates in the National Center for Biotechnology Information (NCBI) database. This comparison was performed to determine the similitudes and differences between both the fungal isolates described here and that have already been identified in the NCBI database. A few fungal genera belonging to Aspergillus and Penicillium species were detected in the data. They were Penicillium digitatum, Penicillium oxalicum, Penicillium citrinum, Aspergillus flavus, Aspergillus niger, and Penicillium chrysogenum. Basic Local Alignment Search Tool (BLAST) shows that penicillium oxalicum, penicillium citrinum, aspergillus flavs and Aspergillus niger performed genetic changes from global characterized isolates of a similar fungal species, with similarity through 93% to 99%. In contrast, P. digitatum and P. chrysogenum isolated in this study showed a 100% genetic similarity to previously registered strains in the NCBI database. These fungi can also produce toxic compounds (mycotoxins), which are damaging to kidneys (nephrotoxic), liver (carcinogenic effects), heart (cardiotoxic), nervous system (neurotoxic), and immune function (immunotoxic). The results emphasize the importance of regular monitoring on the quality and safety of dairy foods and they risk assessment of fungal contaminations and their toxins. These findings underscore the need for strict prophylactic measures, increased public awareness, and sustained research into the effects of these toxins and how to mitigate exposure.