Selenium as essential micronutrient:
Selenium (Se) is an essential nutrient which plays a key antioxidant/catalytic role in animals and humans. It is incorporated either as L-selenocysteine or L-selenomethionine into proteins and enzymes like Glutathion peroxydase, Thioredoxine reductase and Selenoprotein P. It is involved in defense against oxidative stress, regulation of redox status and metabolic modulation of thyroid hormones activities. Selenium is required in particular for reproductive, thyroid and immune functions. In this regard, the European Food Safety Authority has recently approved claims to acknowledge health benefits of Selenium supplementation for the general population. Protective effects of Selenium have also been shown in inflammatory diseases, in cancer as well as in aging.
Selenium deficiency can occur in people dependent on food grown from selenium-deficient soil, as well as in people with severely compromised intestinal function, or those undergoing parenteral nutrition. In this context, selenium supplementation – either alone or in combination – is essential for the treatment or the prophylaxis of deficiencies, and it is of growing interest for health nutrition and clinical indications.
Selenium is present in the food chain under two forms, mineral and organic, in which sodium selenate/selenide and L-selenomethionine (SeMet) are the major representative compounds. Since human cannot produce it, SeMet intake occurs only through diet. Moreover SeMet is characterized by better bioavailability and lower toxicity than inorganic sources of selenium such as selenate/selenide.
As a complementary nutrient, SeMet is available either as such or within selenium -enriched microorganisms using inorganic selenium as substrate. As an innovative alternative, Tetrahedron has developed NutraSelen® as a SeMet precursor.
NutraSelen® as a new source of L-selenomethionine
Based on a new concept of L-selenomethionine (SeMet) precursor, Tetrahedron designed selenium-containing molecules which are proprietary organic compounds (patent No FR2873376 / US7381416 / WO2006008190). The synthesis process of the basic structure NutraSelen® (THD-177 / CAS Number 873660-49-2), i.e., D,L-2-hydroxy-4-(methylseleno)-butanoic acid (HMSeBA), is simple and cost effective compared to that of SeMet. Tetrahedron showed that NutraSelen® can be converted into SeMet following two enzymatic transformations, by yeasts or bacteria (1).
Using NutraSelen®, Adisseo developed under exclusive Tetrahedron’s license the product Selisseo® for animal nutrition. Adisseo’s Selisseo® received a market authorization by the European Commission in May 2013 for its use as feed additive for all animal species (2). This successful development has shown that NutraSelen®/Selisseo® is rapidly converted into SeMet in farm animals (3,4) and is an effective source of SeMet with a safety and bioavailability comparable to that of SeMet (5).
Pure and chemically defined, stable and easy to formulate, NutraSelen® provides a reliable organic source of selenium which has also a great potential for selenium supplementation in human nutrition, including clinical nutrition. For such applications a regulatory dossier has to be filed in Europe.
The health claims that have already been approved by the European Food Safety Authority (EFSA) to support selenium forms authorized for addition to foods and for use in food supplements include:
- Selenium contributes to the protection of cell constituents from oxidative damage (6)
- Selenium contributes to the normal function of the immune system (6)
- Selenium contributes to normal thyroid function (6)
- Selenium contributes to normal spermatogenesis function (6)
- Selenium contributes to the maintenance of normal hair (7)
- Selenium contributes to the maintenance of normal nails (7)
References:
- Simultaneous speciation of selenomethionine and 2-hydroxy-4-methylselenobutanoicacid by HPLC–ICP MS in biological samples – VACCHINA V., MOUTET , YADAN J.C., de BAENE F., KUDLA B., and LOBINSKI R. – 2010 – J. Chromatogr. B, 878:1178-1180
- EFSA Panel on Additives and Products or Substances used in Animal Feed (FEEDAP); Scientific Opinion on safety and efficacy of hydroxy-analogue of selenomethionine asfeed additive for all species – 2013 – EFSA Journal, 11(1):3046 [30 pp.]
- Comparative study of a new organic selenium source v. seleno-yeast and mineral selenium sources on muscle selenium enrichment and selenium digestibility in broiler chickens– BRIENS , MERCIER Y., ROUFFINEAU F., VACCHINA V., and GERAERT P.A. – 2013 – Br. J. Nutr., 110(4):617-624
- Evaluation of the efficacy of 2-hydroxy-4-methylselenobutanoic acid on growth performance and tissue selenium retention in growing pigs – JLALI M., BRIENS M., ROUFFINEAU F., GERAERT P.A., and MERCIER Y. – 2013 – J. Anim. Sci., doi:10.2527/jas.2013-6783
- Effect of 2-hydroxy-4-methylselenobutanoicacid as a dietary selenium supplement to improve the selenium concentration of table eggs – JLALI M., BRIENS M., ROUFFINEAU F., MERCERAND , GERAERT P.A., and MERCIER Y. – 2013 – J. Anim. Sci., 91(4):1745-1752
- EFSA Panel on Dietetic Products, Nutrition and Allergies (NDA); Scientific Opinion on the substantiation of health claims related to selenium and protection of DNA, proteins and lipids from oxidative damage (ID 277, 283, 286, 1289, 1290, 1291, 1293, 1751) , function of the immune system (ID 278), thyroid function (ID 279, 282, 286, 1289, 1290, 1291, 1293), function of the heart and blood vessels (ID 280), prostate function (ID 284), cognitive function (ID 285) and spermatogenesis (ID 396) pursuant to Article 13(1) of Regulation (EC) No 1924/2006 on request from the European Commission– 2009 – EFSA Journal, 7(9):1220 [24 pp.]
- EFSA Panel on Dietetic Products, Nutrition and Allergies (NDA); Scientific Opinion on the substantiation of health claims related to selenium and maintenance of normal hair (ID 281), maintenance of normal nails (ID 281), protection against heavy metals (ID 383), maintenance of normal joints (ID 409), maintenance of normal thyroid function (ID 410, 1292), protection of DNA, proteins and lipids from oxidative damage (ID 410, 1292), and maintenance of the normal function of the immune system (ID 1750) pursuant to Article 13(1) of Regulation (EC) No 1924/2006– 2010 – EFSA Journal, 8(10):1727 [18 pp.]