THE OCCURENCE OF OCHRATOXIN A AND CYCLOPIAZONIC ACID IN MAIZE AND SORGHUM GROWN IN MICROCLIMATIC ZONES OF NIGER STATE

Abstract

Mycotoxigenic fungi and their associated mycotoxins remain a significant threat to growers, consumers, and food regulators. They damage the quality of agricultural crop commodities and impact negatively on food safety. The aim of the study was to determine the occurrence of Penicillium fungi and two mycotoxins in of maize and sorghum in Niger. Sixty-four (64) composite samples (CS) of different varieties of maize and sorghum were collected from stores and markets located in four microclimatic zones of Niger state. Standard procedure was used to isolate Penicillium spp. Ochratoxin A (OTA) and Cyclopiazonic acid (CPA) were extracted and quantified by Enzyme-Linked Immunosorbent Assay (ELISA) and High Performance Liquid Chromatography (HPLC) respectively. The risk assessment as a result of consumption was also determined. The fungi isolate from the samples were: P. verrucosom, P. griseofulvum and P. chrysogenum. The occurrence of Penicillium spp is highest in market maize samples (15.8 %) from wet zone and store samples in dry zone while sorghum had the highest prevalence (16.7 %) in stores sample from driest zone. The OTA was detected in 89.1 % of both maize and sorghum samples at level of 1.799– 75.462 μg/Kg and 0.297 – 49.344 μg/Kg respectively. The CPA was detected in 45.3 % of both maize and sorghum samples at levels of 1.002 – 419.248 μg/Kg and 0.205 – 79.981 μg/Kg respectively. The contamination of the samples collected with OTA had the highest concentration in yellow maize collected from Magama market with 75.462 μg/Kg while the lowest concentration was found in white sorghum collected in Suleja store with the concentration of 0.297 μg/Kg. The co-occurrence of OTA and CPA was high in Magama store with 75.0 % and lowest in Bosso market with 25.0 %. The Estimated Daily Intake (EDI) for male was 0.021 - 0.111 μg/Kg and was 0.020 - 0.423 μg/Kg for female and the Tolerable Daily Intake (TDI) for OTA was 0.014 μg/Kg. there is a health risk to consumers of maize and sorghum due to the contamination of the samples with OTA and CPA in these study areas. Hence, this study advise that consumers of maize and sorghum should ensure proper cooking to reduce the health risk posed by these contaminants.