Some common staple roots and tubers (cassava, yam, sweet
potato and yellow yam) were analyzed for selenium content level using hydride
generation—atomic absorption spectrophotometry (HG-ASS) technique. Results for
duplicate analysis revealed that sweet potato has the highest mean selenium
content (19.2 ± 5.20 μg/kg), followed by yellow yam (18.3 ± 6.97 μg/kg), then
yam (13.6 ± 7.12 μg/kg) and cassava the least (13.0 ± 5.84 μg/kg). In comparing
our results with the literature values, most of the results obtained in this
work such as <1.00, 1.09, 1.91, 2.35 and 11.0 μg/kg were lower while a few
others like 52.6,54.2,72.3 and 81.8 μg/kg were higher than literature values. The
variations could be due to the type of species/variety, geographical location,
total selenium concentration in the soil and its bioavailability. In view of
the importance of Se to human health and considering the levels found in the
staples investigated, we recommend that sweet potato be popularized as a
staple, much more than cassava as it is now the case in Central Nigeria.
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