Evaluation of the aflatoxin contamination and proximate composition of groundnut (Arachis hypogea L.) infected by Aspergillus spp.

Abstract

Aflatoxins B₁ concentration and the proximate composition of groundnuts consumed in six Local Government Areas (LGAs) of Benue State in the Southern Guinea Savannah agro- ecological zone of Nigeria were evaluated. Seed health testing was conducted and associated fungi were identified. Aflatoxin B₁ (AfB₁) produced by Aspergillus flavus were detected and the concentrations quantified using the Enzyme Linked Immunosorbent Assay (ELISA) method. Proximate content of seeds was determined using standard methods of Official Analytical Chemists. Aspergillus flavus Link and Aspergillus niger van Tiegh were the associated fungi found in contaminated groundnut seeds with 15.67 % and 7.67 % occurrence respectively. A combination of both fungi had 4.67 % occurrence. The proximate content of groundnut seed samples ranged from 0.35 % to 40.21 % across the samples analyzed. The proximate analysis indicated that groundnut samples from Agatu LGA had significantly (P ? 0.05) higher protein and fat content of 29.11 % and 40.21 % respectively compared with samples from other LGAs samples. Groundnut samples from Makurdi LGA had significantly (P ? 0.05) higher ash content while samples from Ohimini recorded significantly (P ? 0.05) higher crude fibre. The highest moisture content (9.37 %) was from groundnut seeds from Otukpo LGA. The contamination of the groundnut samples by AfB₁ resulted in a significant (P ? 0.05) reduction in the nutritional quality of the groundnut seeds.

Keywords: Aflatoxin B₁, groundnut, seeds, quality, contamination