Folic acid light sensitivity

Some effects of irradiation on vitamins have been mentioned earlier. It appears that irradiation and heat treatment affect vitamins differendy. Apparendy, vitamins Br B6, B12 and folic acid decompose less under as high a radiation dose as 60 kGy than under autoclaving at 120°Cfor 20 minutes. On the other hand, vitamin C is much more sensitive to irradiation. Generally, the radiosensitive vitamins are also sensitive to light, heat, and oxygen. In fresh foods, the vitamins that are most susceptible to irradiation are A and E. There is also some decomposition of vitamins B, and C. Other vitamins are fairly stable under irradiation. However, for the most part, the vitamins are more susecptible to heat treatment than to irradiation. 

The SP procedure of water-soluble vitamins from multivitamin tablets is particularly challenging due to the diverse analytes of varied hydrophobicities and pfC. Water-soluble vitamins (WSVs) include ascorbic acid (vitamin C), niacin, niacinamide, pyridoxine (vitamin B ), thiamine (vitamin Bj), folic acid, riboflavin (vitamin B2) and others. While most WSVs are highly water soluble, riboflavin is quite hydrophobic and insoluble in water. Folic acid is acidic while pyridoxine and thiamine are basic. In addition, ascorbic acid is light sensitive and easily oxidized. The extraction strategy employed was a two-step approach using mixed solvents of different polarity and acidity as follows ... 

Folic acid was purified in the middle of the twentieth century, and research on the chemical structure of this compound and on its synthesis have been continuously conducted [1,2]. The first total synthesis of riboflavin was achieved in 1935 [3,4]. Riboflavin is a yellow compound, and its solutions emit a yellow-green fluorescence. Riboflavin is sensitive to light, and it gave lumiflavin when exposed to a light under basic conditions. Under neutral conditions it gave lumichrome by releasing the D-ribose moiety. 

The molecular weight of folic acid is 441.40 g/mol. The molecule is very slightly soluble in water, quite soluble in the salt form and insoluble in alcohol. It is sensitive to light and ultraviolet (UV) radiation. Folic acid is readily soluble in dilute solutions of alkali hydroxides and carbonates. Aqueous solutions of folic acid are heat sensitive and decompose rapidly in the presence of light. Solutions should be stored in a cool place protected from light. 

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