http://ssu.ac.ir/cms/fileadmin/user_upload/Mtahghighat/tfood/ARTICLES/chemical_safety/Selenium_in_food_and_the_human_body_A_review.pdf

Selenium in food and the human body: A review

Diets fed to nonruminant animals are composed mainly of feed ingredients of plant origin. A variety of antinutritional factors such as phytin, nonstarch polysaccharides, and protease inhibitors may be present in these feed ingredients, which could limit nutrients that may be utilized by animals fed such diets. The primary nutrient utilization-limiting effect of phytin arises from the binding of 6 phosphate groups, thus making the P unavailable to the animal. The negative charges allow for formation of insoluble phytin-metal complexes with many divalent cations. Furthermore, phytin and protein can form binary complexes through electrostatic links of its charged phosphate groups with either the free amino group on AA on proteins or via formation of ternary complexes of phytin, Ca(2+), and protein. The form and extent of de novo formation of binary and ternary complexes of phytin and protein are likely to be important variables that influence the effectiveness of nutrient hydrolysis in plant-based diets. Nonstarch polysacharides reduce effective energy and nutrient utilization by nonruminant animals because of a lack of the enzymes needed for breaking down the complex cell wall structure that encapsulate other nutrients. Enzymes are used in nonruminant animal production to promote growth and efficiency of nutrient utilization and reduce nutrient excretion. The enzymes used include those that target phytin and nonstarch polysaccharides. Phytase improves growth and enhances P utilization, but positive effects on other nutrients are not always observed. Nonstarch polysaccharide-hydrolyzing enzymes are less consistent in their effects on growth and nutrient utilization, although they show promise and it is imperative to closely match both types and amounts of nonstarch polysaccharides with appropriate enzyme for beneficial effects. When used together with phytase, nonstarch polysaccharide-hydrolyzing enzymes may increase the accessibility of phytase to phytin encapsulated in cell walls. The future of enzymes in nonruminant animal production is promising and will likely include an understanding of the role of enzyme supplementation in promoting health as well as how enzymes may modulate gene functions. This review is an attempt to summarize current thinking in this area, provide some clarity in nomenclature and mechanisms, and suggest opportunities for expanded exploitation of this unique biotechnology.

BOARD-INVITED REVIEW: opportunities and challenges in using exogenous enzymes to improve nonruminant animal production.

Selenium in higher plants: understanding mechanisms for biofortification and phytoremediation

As is the case with any metaphor, parental effects mean different things to different biologists—from developmental induction of novel phenotypic variation to an evolved adaptation, and from epigenetic transference of essential developmental resources to a stage of inheritance and ecological succession. Such a diversity of perspectives illustrates the composite nature of parental effects that, depending on the stage of their expression and whether they are considered a pattern or a process, combine the elements of developmental induction, homeostasis, natural selection, epigenetic inheritance and historical persistence. Here, we suggest that by emphasizing the complexity of causes and influences in developmental systems and by making explicit the links between development, natural selection and inheritance, the study of parental effects enables deeper understanding of developmental dynamics of life cycles and provides a unique opportunity to explicitly integrate development and evolution. We highlight these perspectives by placing parental effects in a wider evolutionary framework and suggest that far from being only an evolved static outcome of natural selection, a distinct channel of transmission between parents and offspring, or a statistical abstraction, parental effects on development enable evolution by natural selection by reliably transferring developmental resources needed to reconstruct, maintain and modify genetically inherited components of the phenotype. The view of parental effects as an essential and dynamic part of an evolutionary continuum unifies mechanisms behind the origination, modification and historical persistence of organismal form and function, and thus brings us closer to a more realistic understanding of life's complexity and diversity.

/pdf/parental-effects-in-ecology-and-evolution-mechanisms-1a37c44o1w.pdf

Parental effects in ecology and evolution: mechanisms, processes, and implications

Carotenoids are among the most prevalent pigments used in animal signals and are also important for a range of physiological functions. These concomitant roles havemade carotenoidbased signals a po ...

/pdf/carotenoid-based-signals-in-behavioural-ecology-a-review-3ulg7qfq8h.pdf

Carotenoid-based signals in behavioural ecology : a review

Selenium (Se) is an essential trace element of fundamental importance to health due to its antioxidant, anti-inflammatory and chemopreventive properties attributed to its presence within at least 25 selenoproteins (Sel). Sel include but not limited to glutathione peroxidases (GPx1-GPx6), thioredoxin reductases (TrxR1-TrxR3), iodothyronine deiodinases (ID1-ID3), selenophosphate synthetase 2 (SPS2), 15-kDa Sel (Sel15), SelH, SelI, SelK, SelM, SelN, SelO, SelP, SelR, SelS, SelT, SelV, SelW, as well as the 15-kDa Sel (Fep15), SelJ and SelU found in fish. In this review, we describe some of the recent progress in our understanding of the mechanisms of Sel synthesis. The impact of maternal Se intake on offspring is also discussed. The key regulatory point of Sel synthesis is Se itself, which acts predominantly at post-transcriptional levels, although recent findings indicate transcriptional and redox regulation. Maternal nutrition affects the performance and health of the progeny. Both maternal and offspring Se supplementations are essential for the antioxidant protection of the offspring. Prenatal Se supplementation provides an effective antioxidant system that is already in place at the time of birth while, postnatal Se supplementation becomes the main determinant of progeny Se status after the first few days of progeny life.

https://www.feedfood.co.uk/download/My_Se_Prot_rev.pdf

Selenoproteins and maternal nutrition.

Effects of supplementing broiler breeder diets with organic selenium and polyunsaturated fatty acids on egg quality during storage

Selenium content in selected foods from the Greek market and estimation of the daily intake.

Bioactive compounds are substances which are present in foods in small amounts and have the ability to provide health benefits. Bioactive compounds include but are not limited to long-chain polyunsaturated fatty acids, vitamins, carotenoids, peptides, and polyphenols. The aim of the present study is to review literature for potential bioactive compounds present in food waste material and discuss the transformation of food waste to animal feed under the perspective that usage of food waste, rather than disposal, may tackle food insecurity and provide health benefits. Finally, applications in poultry and swine nutrition, with emphasis on the presence of fatty acids on food waste material, are discussed.

https://www.mdpi.com/2304-8158/9/3/291/pdf

Bioactive Compounds in Food Waste: A Review on the Transformation of Food Waste to Animal Feed.

Carotenoids in the diet of the laying hen are incorporated into the egg yolk and subsequently into the liver and other tissues of the chicken embryo. Since these pigments are known to provide a range of health benefits to a variety of animals, it is of interest to know whether the effects of maternally derived carotenoids are strictly limited to the embryonic period or if they persist in the progeny after hatching. The aim of this study is to compare the effectiveness of pre-hatch (from the hen's diet) with that of post-hatch (from the progeny's diet) supplementation with carotenoids on the carotenoid status of the chick during the first 4 weeks of post-hatch life. Hens were fed a control diet or a diet supplemented with a carotenoid-rich extract of alfalfa. Eggs from the supplemented hens contained up to 22 times more carotenoids than the controls. The concentration of carotenoids in the livers of chicks hatching from the enriched eggs was initially 29 times greater than in the control chicks. Hepatic carotenoid concentrations in chicks from enriched eggs maintained post-hatch on the control diet were sustained at higher values compared with chicks from control eggs that were fed post-hatch on the carotenoid-supplemented diet, for at least the first 7 days. However, by 14 days, the latter group had overtaken the former in terms of liver carotenoid levels. Thus, under these conditions, maternal effects predominate for at least the first week after hatching, whereas from 2 weeks onwards, the progeny's diet becomes the main determinant of its carotenoid status. Since the antioxidant and immunostimulatory roles of carotenoids are likely to be especially important during the immediate post-hatch period, maternal dietary intake of carotenoids may have important ramifications for the viability of the offspring.

Athanasios C. Pappas

Papers

Selenoproteins and maternal nutrition.

Effects of supplementing broiler breeder diets with organic selenium and polyunsaturated fatty acids on egg quality during storage

Selenium content in selected foods from the Greek market and estimation of the daily intake.

Bioactive Compounds in Food Waste: A Review on the Transformation of Food Waste to Animal Feed.

Embryonic development within carotenoid-enriched eggs influences the post-hatch carotenoid status of the chicken.