Assessment of fungal species in some spices using molecular study with detection of their mycotoxins using chromatography analysis

Abstract

Spices are food flavouring agents that are highly used in Iraq. However, they may be contaminated by toxicogenic fungi and subsequent production of mycotoxins. The aim of this study was to investigate the contamination of commonly used spices with fungi using polymerase chain reaction (PCR) assay and to detect fungal mycotoxin using high‐performance liquid chromatography. Thirty‐five spices (seven samples from each black pepper, red pepper, turmeric, cumin and ginger) were cultured on an appropriate medium to identify various fungi species. Later on, the toxigenicity of Aspergillus flavus and Aspergillus niger was determined using a PCR assay. The fungal mycotoxins, including aflatoxins and ochratoxins, were then determined through a high‐performance liquid chromatography using the validated Quick, Easy, Cheap, Effective, Rugged, and Safe (QuECHERS) method. Aspergillus species were the predominantly isolated fungi, followed by Penicillium and Fusarium. The PCR results indicate the high toxigenicity of A. flavus as 85.7% of the strains had aflQ/aflR genes and 79% had PKS15KS/PKS15C‐MeT genes. Regarding mycotoxin contamination in spices, the highest rates of aflatoxins and ochratoxins were found in black pepper (5.913 μg/kg) and red chilli (6.9055 μg/kg), respectively. Spices are susceptible substrates for the growth of mycotoxigenic fungi. Thus, regular effective surveillance and quality control procedures are highly recommended.