The Importance of Selenium Biofortification in Food Crops

Selenium (Se) is an essential element for maintenance of human health. Although it has not been confirmed an essential nutrient in higher plants, there is increasing evidence that Se is a beneficial element for plants, as an antioxidant and a promoter of plant growth. Today, the investigation is directed to elucidate the specific biochemical mechanisms that underlie this positive effect in plants. This ability of some plants to accumulate and transform Se into bioactive compounds has important implications for human nutrition and health. Because Se deficiency is a common problem worldwide, plants are an excellent source of dietary Se than can help to alleviate this problem. It is considered that the beneficial role of Se in human nutrition and health is attributed both to Se compounds and to its presence within selenoproteins; however, it is important to know which Se species are beneficial or detrimental to human nutrition. This review presents the roles of Se in plant and human nutrition; particular attention is paid to the importance of plant Se biochemistry, the strategies to increase Se density in crops by biofortification, the necessity of reaching the correct Se levels through diet and the importance of increased Se to a whole population. Keywords: Biofortification, cancer, glutathione peroxidase, selenium, selenocompounds, selenocysteine, selenomethionine, selenoproteins, speciation, antioxidant, plant growth, nutrition, bacteria, hyperaccumulator plants, species, bioavailability, soils