Determination of Aflatoxins in Maize (Zea Mays L.) Samples from Dera and Fogera Districts of South Gondar Using LC-MS/MS

Abstract

Maize (Zea mays L.) is plant genetics and a member of the grass family, which is believed to have originated from Mexico and introduced to Ethiopia in 1600s to 1700s. Maize contains approximately 72 % starch, 10 % protein, and 4 % fat and supplying an energy density of 365 Kcal/100 g. However, the grain is vulnerable to degradation by Aflatoxins mainly produced by Aspergillus flavus and Aspergillus parasiticus, which have adverse effects on humans and livestock that ingest Aflatoxin contaminated food products and feeds. Contamination of maize grain by fungi leads to losses in quality and quantity of production. Aflatoxins are fungal secondary metabolites, which are harmful to human and animal health. The objective of this study was to determine the major Aflatoxin B1, Aflatoxin B2, Aflatoxin G1 and Aflatoxin G2 in maize sample from two districts of South Gondar Zone. The Aflatoxins were extracted from maize with ACN: H2O (84:16) and detected by LCMS/ MS. Mass spectrometry is a very sensitive technique and is widely regarded as having good selectivity. A good linearity of standard calibration was found for AFB1, AFB2, AFG1 and AFG2 at a range of 0.1–15 ppb. Regression coefficient (R2) values were >0.999, whereas slope and intercept were in the range of 0.9776-0.9972 and 0.0147-0.1167, respectively. The average recoveries for spiked sample of the two districts were range from 65.95 to 97.60 %. The mean level of Aflatoxins in this study was below limit of detection of AFB1 (0.0253 ppb), AFB2 (0.0255 ppb), AFG1 (0.0257 ppb) and AFG2 (0.0258 ppb) limit of quantification range from (0.084-0.086 ppb) in maize samples. Further monitoring of Aflatoxins in maize from different regions of the country is justified in order to conclusively determine the actual safe/risks from Aflatoxins and possibly low Aflatoxins-risk maize production areas.