Selenium Biofortification: Roles, Mechanisms, Responses and Prospects

Abstract

The trace element selenium (Se) is a crucial element for many living organisms, including soil microorganisms, plants and animals, including humans. Generally, in Nature Se is taken up in the living cells of microorganisms, plants, animals and humans in several inorganic forms such as selenate, selenite, elemental Se and selenide. These forms are converted to organic forms by biological process, mostly as the two selenoamino acids selenocysteine (SeCys) and selenomethionine (SeMet). The biological systems of plants, animals and humans can fix these amino acids into Se-containing proteins by a modest replacement of methionine with SeMet. While the form SeCys is usually present in the active site of enzymes, which is essential for catalytic activity. Within human cells, organic forms of Se are significant for the accurate functioning of the immune and reproductive systems, the thyroid and the brain, and to enzyme activity within cells. Humans ingest Se through plant and animal foods rich in the element. The concentration of Se in foodstuffs depends on the presence of available forms of Se in soils and its uptake and accumulation by plants and herbivorous animals. Therefore, improving the availability of Se to plants is, therefore, a potential pathway to overcoming human Se deficiencies. Among these prospective pathways, the Se-biofortification of plants has already been established as a pioneering approach for producing Se-enriched agricultural products. To achieve this desirable aim of Se-biofortification, molecular breeding and genetic engineering in combination with novel agronomic and edaphic management approaches should be combined. This current review summarizes the roles, responses, prospects and mechanisms of Se in human nutrition. It also elaborates how biofortification is a plausible approach to resolving Se-deficiency in humans and other animals.

Is Nano-Biofortification the Right Approach for Malnutrition in the Era of COVID-19 and Climate change?

“…The production of biofortified crops enriched in macro-or micro-nutrients has been applied several years ago such as Ca (Pessoa et al 2021), Cu (Yusefi-Tanha et al 2020a), I (Budke et al 2020(Budke et al , 2021, Fe (Coelho et al 2021;Okwuonu et al 2021), Mg (Kumssa et al 2020), Se (Lessa et al 2020;Hossain et al 2021;Trippe III and Pilon-Smits 2021), Zn (Okwuonu et al 2021 andSilva et al 2021). Using some vitamins (Fitzpatrick and Chapman 2020;Jiang et al 2020;Tiozon et al 2021) and other essential compounds like carotenoids (Watkins andPogson 2020 andZheng et al 2020) and folate (Strobbe and Van Der Straeten 2017;De Lepeleire et al 2018;Viscardi et al 2020) for human health also have been applied in biofortification strategies.…”

Biofortification with selenium increases bioactive compounds and antioxidant capacity in tomato fruits

“…The citric acid expressed in titratable acidity, is produced from the oxidation of sugars during respiration and metabolic activity (García-Sahagún, Martínez, Avendaño, Padilla, and Izquierdo, 2009;Beckles, 2012). The addition of Se to the nutrient solution influences the activation of respiration and production of ethylene (Hossain et al, 2021;Naseem et al, 2021) since it controls the synthesis of citric acid, activating phosphorylation as part of respiration and the synthesis of ethylene dependent on the energy available to generate organic acids (Larskaya, Barisheva, Zabotin, and Gorshkova, 2015); decreasing the ripening processes as the fruit cycle progresses (Garduño and Márquez, 2018). Tomatoes are climacteric fruits and their ripening is accompanied by changes in flavor, texture, color and aroma.…”

“…Absorption, distribution and translocation of Se within plants is determined by the translocation of the plant, the activity of membrane transporters, the form and concentration of Se in the plant (Gupta and Gupta, 2017;White, 2018;Zahedi et al, 2019). The greater absorption of this element could have been due to selenite is better captured by passive diffusion without participation of membrane transports as it is chemically similar to phosphate (Hossain et al, 2021), commonly synthesized as SeMet, methyl-SeCys or ɣ-glutamyl-Se-SeCys (ɣ-Glu-MeSeCys) (Jha and Warkentin, 2020), since they are incorporated into metabolic pathways such as plant selenoproteins to form the most important part of active center of its enzymatic activities (Kieliszek, 2019) and a greater benef it of improved antioxidant activity (White, 2018). In this regard, the requirement of daily intake of Se per day in babies of 6 months' age is 15 mg, for babies from 7 months to 3 years of age is 20 mg, children from 4 to 8 years is 30 mg, children from 9 to 13 years of age is 40 mg, adolescents from 14 to 18 years 55 mg and adults from 19 to 71 years of age 55 mg (Liu et al, 2019).…”

“…One strategy to increase Se content in food is through biofortif ication consisting potentiate the bioactivity and Se content in the edible parts of plants (Gaucin-Delgado et al, 2020). Fertilization is the most practical way to introduce Se into the food supply chain through agronomic practices; biofortif ication has been done successfully in different cultures increasing food and nutrition security of individuals, families and general population (Schiavon and Pilon, 2017), following improved agronomic characteristics, increasing food production and content of phytochemicals (Hossain et al, 2021), which help address nutritional def iciencies that are present in human diet (Bocchini et al, 2018); allowing faster to reach poorest communities, which have no resources to buy nutritional supplements suitable for the recommended daily intake (Mikula et al, 2020).…”

Bioinformatics Analyses Reveal the Prognostic Value and Biological Roles of SEPHS2 in Various Cancers

“… 4 Se interacts with amino acids to form selenoproteins which regulate physiological functions in humans and animals. 5 So far, 25 types of selenoproteins have been identified in humans, including selenophosphate synthetases (SEPHS1-2), glutathione peroxidases (GPX1-4, GPX6), iodothyronine deiodinases (DIO1-3) and thioredoxin reductases (TXNRD1-3). 6 Selenocysteine (Sec) is considered the main form of Se in proteins and the active center of 25 selenoproteins.…”