Selenium Accumulating Leafy Vegetables Are a Potential Source of Functional Foods

Selenium deficiency in humans has been associated with various diseases, the risks of which can be reduced through dietary supplementation. Selenium accumulating plants may provide a beneficial nutrient for avoiding such illnesses. Thus, leafy vegetables such asAmaranthus hybridus,Amaranthussp.,Cucurbita maxima,Ipomoea batatas,Solanum villosum,Solanum scabrum, andVigna unguiculatawere explored for their capabilities to accumulate selenium when grown on selenium enriched soil and for use as a potential source of selenium enriched functional foods. Their selenium contents were determined by spectrophotometry using the complex of 3,3′-diaminobenzidine hydrochloride (DABH) as a chromogen. The mean concentrations in the leaves were found to range from7.90±0.40to1.95±0.12 μg/g dry weight (DW), withC. maximaaccumulating the most selenium. In stems, the accumulated selenium content ranged from1.12±0.10 μg/g inAmaranthussp. to5.35±0.78 μg/g DW inC. maximaand was hence significantly different (P<0.01). The cancer cell line MDA-MB-231 was used in cytotoxicity assays to determine the anticancer potential of these extracts. With exception ofS. scabrumandS. villosum, no cytotoxicity was detected for the selenium enriched vegetable extracts up to 100 μg/mL concentration. Hence, following careful evaluation the studied vegetables may be considered as selenium enriched functional foods.