Are all Brazil nuts selenium-rich?

摘要

Brazil nuts (Bertholletia excelsa, Lecythidaceae family) from the Amazon region of Brazil are consumed worldwide, and are known as the richest food in selenium (Se). Depending on the soil Se content, concentrations of Se range from 5 to 512 mg/kg (Dumont et al., 2006; Chang et al., 1995). Brazil nuts are a convenient dietary source of Se. The dietary consumption of one nut per day could avoid the need for other Se-fortified foods or expen sive Se food supplements (Thomsom et al., 2008). It is known that the variation of Se concentration in Brazil nuts results from different growing conditions(such as soil Se contents), as well as among individual nuts (Secor & Lisk, 1989; Chang et al., 1995). However, there are few studies that characterize these local and regional variations of Se concentrations. Thus, this study aimed to evaluate the concentration of Se in Brazil nuts growing in different areas of the Amazon Region. This will show how the Se variability in soil, as well as genotypic variability impacts the Se concentration in Brazil nuts.