Selenium biofortification for human and animal nutrition

Abstract

Selenium (Se) is an essential trace element, playing a crucial role in the functioning of enzymes in humans and animals and protecting cells from damage by free radicals (Hatfield et al., 2014). Selenoproteins, that is, proteins containing selenium, are best known as antioxidants and catalysts for the production of active thyroid hormone (Rayman, 2012). Although the essential role of Se for the growth and survival of plants has not been confirmed yet, it is a beneficial element for plants, which can enhance resistance to stress (see Chapter 8). Despite the importance of this trace element, intake of Se by animals and humans in a wide range of countries, including several countries inWestern Europe and East and Central Africa, is still low, resulting in Se deficiency and causing negative health effects, including increased risk of mortality, poor immune function, and cognitive decline (Broadley et al., 2006; Rayman, 2012; Roekens et al., 1986). An estimated one billion people around the world are affected by selenium deficiency, because of low Se intake (Poblaciones & Rengel, 2017; Rayman, 2004). The recommended daily Se intake in an adult human diet is 0.04–0.4 mg per person per day (Food and Agriculture Organization of the United Nations/World Health Organization [FAO/WHO], 2001). Besides, farm animals (Dermauw et al., 2013) and pets (van Zelst et al., 2016) can be affected by Se deficiencies, leading to economic losses. Therefore, the Se content in the human