CHAPTER 17. Biofortification of Fruit and Vegetables with Selenium

Se is a trace element essential for human health due to the presence of several Se-requiring enzymes in the human body. Inadequate dietary intake of Se, leading to potential Se deficiency, has been a problem for populations living in countries with a low Se content in their soils (and therefore in the crops grown in them), such as Finland and New Zealand. An increased dietary intake of Se has been shown to provide health benefits beyond that of preventing the symptoms of Se deficiency, by reducing oxidative stress and boosting heart and lung function, and by reducing the incidence of certain cancers. Se supplementation of various fruit and vegetable species to levels within dietary recommendations is easily possible, with some Se-supplemented products (e.g., spinach, potatoes, tomatoes) being released commercially. Current research is investigating a second generation of crops enriched in organic forms of Se possessing powerful antioxidant or anticancer activity, such as methylselenocysteine or selenoglucosinolates. The product safety requirements for Se supplementation of fruit and vegetables must be rigorous to protect agricultural workers and consumers. For a commercial product, the biological variation in Se uptake and accumulation between individual plants or edible plant parts needs to be monitored and controlled through extensive product testing.