Unusual pattern of aflatoxins and ochratoxin in commercially grown maize varieties of Pakistan

摘要

The contamination of food with mycotoxins could be a major health risk. Identification and quantification of mycotoxins in maize are essentially required to guarantee food safety. Seven commonly grown maize cultivars were sown at semi-arid conditions in Pakistan. After harvesting plants, total aflatoxin (AFs), aflatoxins B-1 (AFB(1)), B-2 (AFB(2)), G(1) (AFG(1)), G(2) (AFG(2)), and ochratoxin-A (OTA) contents were determined in maize flour using high performance liquid chromatography (HPLC). Results showed an unusual pattern of AFs in maize with a higher concentration of AFG(1) in all maize varieties. The AFB(1) was not found in most of the samples, however, all maize grains contained AFs above the maximum tolerable limit (20 mu g/kg). The highest concentration of AFs was recorded in Ayub-1/26 maize (362.8 mu g/kg). Ochratoxin-A (OTA) was detected in 71% maize samples ranged from 2.14 to 214 mu g/kg. The highest OTA and microbial load were recorded in Ayub-2/27 grains that exceeded the FDA limit (50 mu g/kg). These results indicated the higher prevalence of total AFs, AFG1, and OTA at the harvest stage of maize that could pose significant health hazards to humans and livestock.