Folates: Key Nutrients to Remember


Affiliations

  • Ibn Khaldoun University, Laboratory of Agro-Biotechnology and Nutrition in semi-arid area, Faculty of Natural Sciences and Life, Tiaret, Algeria
  • Badji Mokhtar Annaba University, Laboratory of Applied Biochemistry and Microbiology, Faculties of Sciences, Annaba, Algeria

Abstract

Folic acid or vitamin B9 or pteroylglutamic acid, is a relatively simple molecule with two characteristics; firstly, it must be reduced by 2 or 4 hydrogen atoms to be metabolically active which makes it sensitive to oxidation and must be protected by ascorbic acid, secondly it may include in addition to the constituent residues of the molecule, 1-7 glutamate residue at one of its ends. These polyglutamate forms that make up the largest share of food folate, must be deconjugated by a specific enzyme present in the intestinal lumen before being absorbed in the jejunum. It is in the methylated form after passing through the enterocyte it is transported in the blood, excreted in bile and reabsorbed. It must be demethylated to integrate folic cell cycle and methyl transfer, that allows the synthesis of methionine (only possible in the presence of vitamin B12), purine, serine and especially thymidylic acid, constitutive DNA. As a methyl donor that plays a fundamental role in cerebral and nervous metabolism. Folates are involved in cell division thus; any folic acid deficiency causes a slowdown in rapid multiplication systems which may lead to red blood cell disorders (macrocytic anemia), immunity, and neural tube defects, in addition to physiological disorders (cardiovascular, cancer ...). Folic acid supplementation appears to allow the correction of these disorders.

Keywords

Deficiency, Disorders, Folic acid, Supplementation

Full Text:

References

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