biochemistry

1. Vitamins
ESTHER ISSAC

2. CLASSIFICATION
Fat soluble:
Vitamins: A,D,E,K
Water soluble:
Non B complex vitamin: C
*Energy releasing:
Vitamins: B1,B2,B3,B5,B6,B7
*Hematopoietic:
Vitamins: B9,B12

3. Fat soluble Water soluble
*Stored in the body * Not stored in the body
*Excess is not excreted
usually except in cystic
fibrosis and pancreatic
insufficiency.
*They act as precursors
for co-enzymes and
antioxidants( beta-
carotene & Vitamin E)
*Excess is excreted in
urine.
* They act as (B-
complex) co-enzymes
and (vitamin-C )
antioxidant

6. Wald’s visual cycle

7. RDA
1 retinol equivalent= 1µg retinol
=6µg beta carotene
=12µg other carotenes
For males: 3,500 IU
For females:2,500 IU

8. Biological Functions
Steroid like function in growth and differentiation
Effect on epithelia
Prevent keratin synthesis
Retinyl phosphate in synthesis of glycoproteins
Synthesis of transferrin
Synthesis of cholesterol
Caroteinoids play role as antioxidants & reduce risk of
heart attacks

9. Deficiency manifestations
*Nyctalopia
*Xerophthalmia & Bitot’s spots
*Keratomalacia
*Sterility in males
*Keratinization of GI,Urinary & Respiratory tracts
* Formation of urinary calculi

10. Keratomalacia Bitot’s spots

11. Hypervitaminosis
*Dermatitis
*Enlargement of liver
*Skeletal decalcification
*Tenderness of long bones
*Loss of weight, hair, irritability
*Joint pains
*Increased synthesis of lysosomal hydrolases

12. Therapeutic uses
Maternal hepatic accumulation of Vitamin A
in fetus occurs during last trimester, hence
preterm infants are relatively deficient in
Vitamin A.
Its administration may reduce mortality &
complications in patients with measles,
especially children due to repair of epithelial
cells.

13. Acute promyelocytic leukemia is treated by all
trans retinol administration before chemotherapy.
Use of retinoic acid preparation as topical
dermatological agents in treatment of psoriasis,
acne & several other skin diseases due to
epithelial regeneration capacity.
Some pre-cancerous lesions seem to respond to
treatment with Caroteinoids.

16. Absorption

17. RDA
For males:15 IU
For females:12 IU
Requirement α Intake of PUFA

19. Prevents sterility by protecting germinal
epithelium
Prevents oxidation of PUFA, Vitamin A &
Caroteinoids
Stabilizes co-enzyme Q of ETS
Needed for optimal amino acid absorption
Protects liver from carbon tetrachloride
Required for proper storage of creatinine in
skeletal muscle
Necessary in heme synthesis by enhancing
activity of δ-amino levulinic acid synthase &
hydratase
Prevents cancer & heart diseases

20. Deficiency manifestations
*Sterility
*Degenerative changes in muscle
*Megaloblastic anemia
*Changes in CNS

21. THE END
Thank You for being
patient…