Vitamin B9 (Folic Acid or Pteroylglutamic Acid)

 Vitamin B₉ (Folic Acid or Pteroylglutamic Acid)

(Fermentation residue factor)

Introduction

The existence of this nutritional factor was suggested by Day. It was named folic acid (L. folium) by Mitchell, Snell and Williams, because of its isolation from spinach leaf. The chemical structure was established in 1945.

It has also been known as vitamin M, Liver Lactobacillus casei factor and Streptococcus lactis R (SLR) factor.

Chemistry

Folic acid is a group of chemically different compounds. The simplest form of Pteroylglutamic acid (PGA) contains a pterin derivative residue connected to para amino benzoic acid and glutamic acid. Folic acid is converted into tetra hydro derivative in the body which after taking up a formyl (-CHO) group forms folinic acid and also known as citrovorum factor (CF).

Properties

·        yellow compound

·        slightly soluble in water 

·        soluble in dilute alcohol

·        destroyed by light

·         can be precipitated as barium or lead salt

Distribution

Animal sources

·        Liver

·        Kidney

·        Sea foods

Plant sources

·        Green leafy vegetables

·        cauliflower

·        Peanuts

Functions

(1) Folinic acid acts as a coenzyme (coenzyme P) in the transfer of formyl and hydroxymethyl groups in different biological systems (e.g. in the biosynthesis of purine, synthesis of the methyl group of methionine, ere,) in the one-carbon metabolism.

(2) It is required for the synthesis of deoxyribonucleic acid in the nuclei of the cells,

(3) Takes part in the formation and maturation of the red cells.

Deficiency signs

Megaloblastic anaemia especially occurring during pregnancy

Daily requirement

Average daily diet of adults contains about 50 micro grams, which seems to be adequate.