Journal of Food Science and Technology (ISSN: 2141-5455) Vol. 5(1) pp. 12-20, January, 2014. DOI: http:/ Copyright © 2014 International Research Journals


Full Length Research Paper

Rapid assessment of aflatoxin contamination of groundnuts by thin layer chromatography and competitive enzyme linked immunosorbent assay from selected divisions of Busia county in Kenya

David Ondieki1,2, Samuel T. Lutta2; Maurice O. Okoth2, Paul Kering2

1Directorate of Occupational Safety and Health Services, Kenya.

2Department of Chemistry and Biochemistry, University of Eldoret, Kenya.

Corresponding author email:

Received January 13, 2014; Accepted January 20, 2014



Aflatoxins are naturally occurring mycotoxins that are common contaminants of groundnuts thereby presenting a health concern in particular where proper storage of agricultural products is difficult. In this study, groundnut samples were collected from farmers and traders in Busia County. The samples were ground to fine powder and subjected to a preliminary Thin Layer Chromatography (TLC) analysis for detection of contaminated samples. In TLC analysis, the aflatoxin types B1, B2, G1 and G2 were identified with 25.6% of the samples found to be contaminated. The positive samples were further subjected to Enzyme-Linked Immunosorbent Assay (ELISA) test using Stat Fax® 3200 ELISA machine for the purpose of cumulative quantification. AF-B1 (aflatoxin B1) was the most dominant contaminant of both market and farm samples with 73% of the contaminated samples found to contain AF-B1. Market samples were more contaminated than farm samples. Contamination levels ranged from a minimum 6.9 ppb to a maximum of 88.7 ppb giving a range of 81.8 ppb, a mean of 44.9 ppb and a standard deviation of 21.78. Contamination exceeded the WHO and Kenya Bureau of Standards (KEBS) maximum allowed limit of 20 ppb and 10 ppb respectively and is therefore a hazard to consumers

Keywords: Aflatoxin Concentration (ppb), Aflatoxin B1, TLC, ELISA.