Assessment of fungi incidence, seed germination and aflatoxin contamination of groundnut (Arachis hypogaea L.) from Lagos, Nigeria

Abstract

Groundnut (Arachis hypogaea L.) is a legume of high nutritive and market value usually contaminated by aflatoxin. The evaluation of aflatoxin contamination of groundnut entering the food system through the markets is necessary to ascertain the quality of the groundnut sold and subsequently advice groundnut consumers. The study assessed the aflatoxin B1 (AfB1) contamination levels in groundnut sold in some markets in Lagos, Nigeria. Groundnut seeds were sampled from five Local Government Areas (L. G.A) of Lagos State namely: Agege, Eti-Osa, Ifako Ijaye, Ketu and Oshodi. The samples were packaged in envelopes and transported to the Mycotoxin laboratory of the Federal University of Agriculture, Makurdi, Nigeria for assessment of the fungi infections, seed germination and aflatoxin contamination levels. The experiment for the assessment of fungi infecting and germination of groundnut seeds was laid out in a completely randomized design in ten replicates. Detection of AfB1 present in the groundnut samples was done using Enzyme Linked Immunesorbent Assay (ELISA) method in three replicates. Result showed that Aspergillus flavus Link was the most frequently isolated fungi with 46 % incidence, Lasiodiplodia theobromae Pat. had 20 % incidence, Aspergillus niger van Tiegh with 11 % and Fusarium verticollioides Sacc. 7 % incidence. The moisture content of groundnut seeds ranged between 7.20 % and 6.53 %. Aflatoxin B1 concentrations in groundnut samples was highest in Eti Osa LGA (5.11 µg/kg) while Oshodi LGA had the least concentration (3.09 µg/kg). Groundnut samples from the five Local Government Areas of Lagos State were contaminated with AfB1 at concentration levels below the safe limits for human consumption and health of 20µg/kg. Management of fungi infection on the field is recommended to prevent field to store contamination of groundnut seeds.

Evaluation of Raw Groundnuts from Makurdi Markets in Nigeria for Aflatoxin B1

“…Using high performance liquid chromatography, Ifeji et al [18] analyzed raw and roasted peanuts sold in Niger state, Nigeria, and reported AFB 1 levels of 4 -188 μg/kg, while levels of 74.03 -82.12 µg kg -1 were determined for groundnuts from the Niger-Delta region in Nigeria [19], and AFB 1 levels of between 3.09 and 5.11 were detected in shelled groundnut seeds collected from five LGAs in Lagos, Nigeria [20]. Ekhuemelo and Abu, [21], sampled raw groundnut seeds stored for one to two years from six Local Government Areas (LGAs) of Benue state and evaluated them for AFB 1 using the ELISA method.…”