Total aflatoxins load and phytochemical composition of Cola nitida (Kola Nut) samples purchased within Jos metropolis

Abstract

The total Aflatoxin load and phytochemicals in Cola nitida (kolanut) were quantified and qualified respectively. Enzyme linked immunosorbent assay (ELISA)-Colorimetric technique and standard qualitative procedure for phytochemical screening were applied. Prior to the quantification of total aflatoxins, samples were extracted using extraction mixture containing methanol and water in ratio 70:30 v/v, aflatoxin conjugate substrate solution, stop solution and aflatoxin standard were used to achieve the setout objectives of this work. Ten samples each of red and cream colour Cola nitida were purchased fresh and divided into two: a portion each of both varieties was sundried whereas others were kept in a damp place to retain moisture. InStat3 statistical software was used to analyse the data and the student’s t-test was chosen to analyse the results obtained. P value of 0.01 was considered significant. The results obtained indicated the dampened samples to be more contaminated with aflatoxins compared to the dried forms albeit relative to the maximum limit of total aflatoxins for both ready to eat food (4μg/kg) and other foods (9μg/kg), both types had higher total aflatoxin content (p<0.01). The results were: 13.3μg/kg for dried red, 16.05μg/kg for wet red, 10μg/kg for dried cream and 15.8μg/kg for wet cream. Red species appeared to have moreaflatoxin both in the damp and dried forms. Phytochemicals such as tannins, cardiac glycosides were present in all the samples. However, dried forms of the samples contained almost all the phytochemicals analysed but the damped forms did not contain resins and terpenes. The damped form of the cream coloured samples did not contain terpenes.