Terminology: 1920, originally vitamine (1912) coined by Polish
biochemist Casimir Funk (1884-1967), from Latin vita "life" +
amine , because they were thought to contain amino acids. When
it became clear that some of them were not amines and did not
even contain nitrogen, Drummond suggested the modification
that led to the term vitamin.
Definition: vitamin is an organic compound/molecule required as a
nutrient n small amount, by an organism.
The distinguishing feature of the vitamins is that they generally
cannot be synthesized by mammalian cells and, therefore, must
be supplied in the diet.
Fat soluble vitamins:
1. The fat soluble vitamins do not serve as coenzymes but rather act
directly, or bind to specific receptors in cell nucleus.
2. They are absorbed in association with dietary fat, bile is
required for absorption. Ulcerative colitis can lead to
3. Vitamins A and D are stored in liver and it takes time to
bring on a deficiency state. However they are more likely
to cause toxicity on overdosage.
is the blanket term for retinoids, biologically active compounds that occur
naturally in both plant and animal tissues.
According to some research, having more than an average of 1.5mg
a day of vitamin A over many years may affect your bones, making
them more likely to fracture when you are older.
Vitamin A is a fat-soluble vitamin.
Types of vitamin A:
1. Preformed vitamin A
2. pro-vitamin A
Vitamin A is also available in dietary supplements, usually in the form of retinyl
acetate or retinyl palmitate.
Sources of Vitamin A
Top sources of vitamin A
1. Beef liver
2. Egg yolk
3. Cheddar cheese
4. Fortified milk
5. Top sources of beta-
6. Sweet potato
12. Spinach and collard
Also called Anti-beri beri factor, anti-neuritic factor
• Involved in carbohydrate, fats, amino-acid, glucose, and alcohol metabolism.
• Required as co-enzyme in enzymatic reactions that involve the transfer of an
• Essentially non-toxic.
• Can be synthesized by plants and some micro-org., but not usually by animals.
• Human being require it from diet
• The body can store upto 30mg in its tissues.
• Half-life 9-18 days, excreted via kidney
• Whole wheat flour, unpolished rice, beans, nuts and yeast are good sources. Also
present in liver, meat and eggs.
Thiamine contains substituted pyrimidine ring (dimethyl 6-amino pyrimidine) and a
substituted thiazole ring (methyl hydroxyl ethyl thiazole), connected by a methylene
Synthesis of Pyrimidine moiety (1) of thiamine
Synthesis of Thiazole moiety (2) of Thiamine
Condensation of (1) and (2) to form Thiamine
STRUCTURE ACTIVITY RELATIONSHIP (SAR):
Essential features for activity:
• Methylene bridge.
• Amino group in the pyrimidine ring.
• Hydroxy ethyl group at the thiazole ring.
• Methyl group of pyrimidine ring, when replaced by:
a- Ethyl or propyl groups gives an active compound.
b- Butyl group gives inactive compound.
Oxythiamine is a competitive inhibitor.
Neopyrithiamine prevent phosphorylation of hydroxy ethyl group that is essential for
activity of the vitamin.
• Riboflavin was once called Vitamin G.
• This vitamin plays an important role in the metabolism of lipids, proteins, and
• The vitamin acts as a precursor for the synthesis of cofactors flavin adenine
dinucleotide (FAD) and flavin mononucleotide (FMN). These coenzymes are
involved in a wide range of redox reactions, involved in Activation of vitamin B12
and folate, Protection of erythrocytes and other cells from oxidative stress.
• Milk, eggs, leaf vegetables, legumes, and mushrooms are good sources of the
vitamin. Intestinal bacteria are also known to synthesise riboflavin.
• Added as food colouring agent, and Fortify some foods as baby foods, breakfast
cereals, sauces, processed cheese, fruit drinks and vitamin-enriched milk).
It chemically has a three rings structure (isoalloxazine) linked to ribityl moiety.
Vit B2 = Riboflavin
STRUCTURE ACTIVITY RELATIONSHIP:
The ribitol-like moiety can be cleaved from the vitamin, resulting in lumiflavin. It is
produced by the photolysis of Riboflavin, act as riboflavin uptake inhibitor.
Riboflavin decomposes when exposed to visible light. This characteristic
can lead to riboflavin deficiencies in newborns treated for
hyperbilirubinemia by phototherapy.
The severe deficiency of riboflavin is known as ariboflavinosis
• Migraine headaches in use of high doses of riboflavin
• Improve memory
• Healthy development of the fetus
• Boost the body's level of glutathione which is an anti-oxidant.
• Also called Vitamin P
• The body can also synthesise niacin from the essential amino acid, tryptophan. So it
is not a true vitamin in the strictest definition since it derives from aminoacid.
• Niacin synthesized in liver by tryptophan but the synthesis is extremely slow and
require Vit. B6.
• Precursor of important coenzymes, nicotinamide adenine dinucleotide (NAD), and
nicotinamide adenine dinucleotide phosphate (NADP) which function as cofactors
for numerous dehydrogenases, e.g., lactate and malate dehydrogenases.
• Food sources of niacin include tuna, venison, beef, chicken, avocados, tomatoes,
whole grain products, and shiitake mushrooms.
Niacin is a pyridine derivative with a carboxyl group at 3rd position.
Both nicotinic acid and nicotinamide are derivatives of niacin and can serve as the
dietary source of vitamin B3.
Nicotinic acid Nicotinamide
Niacin chronic deficiency results in Pellagra.
•Decrease blood cholesterol levels and reduce the risk of heart attack.
• Niacinamide used on a long-term basis to prevent the onset of juvenile diabetes
• Involved in production of sex and stress hormones.
• Improve blood circulation.
• Regulate blood sugar level.
It is an important precursor of coenzyme-A (CoA) that assists the following reactions:
Formation of Sterols (Cholesterol and 7-Dehydrocholesterol).
Formation of Fatty acids.
Formation of Keto acids such as Pyruvic acid.
Pantothenate is required for the metabolism of carbohydrate via the TCA cycle and all
fats and proteins.
Only the R enantiomer of the vitamin is biologically active .i.e D-panthenol.
Meat, whole grains, cereals are major sources of pantothenic acid. Other sources of the
vitamin include avocados and broccoli.
It is a peptide substance composed of Pantoic acid and b-Alanine.
It can be present as the Calcium salt or the Alcohol “Pantothenol.
HO CH2 C CH NH CH2
HO CH2 C CH NH CH2
Because pantothenic acid is common in the diet, cases of deficiency are rare. When
occur it leads to Paresthesias
• Maintain growth of Nervous system of the body
• Building cells of the body
Helps in function of adrenal gland
• Increase immunity of the body.
• D-panthenol is an analogue of Panthothenic acid. It is a biologically active
enantiomer of Panthenol. Use to to relive gas retention and Topically for:
Vitamin B6 refers to a group of chemically very similar compounds which can be
interconverted in biological systems. Vitamin B6 is part of the vitamin B complex
group, and its active form, Pyridoxal 5'-phosphate (PLP) serves as a cofactor in many
enzyme reactions in amino acid, glucose, and lipid metabolism
Pyridoxal 5'-phosphate (PLP)
The classic clinical syndrome for vitamin B6 deficiency is
a seborrhoeic dermatitis-like eruption, atrophic glossitis
• angular cheilitis,
• intertrigo, and
• neurologic symptoms of somnolence,
• confusion, and
• neuropathy (due to impaired sphingosin synthesis)
• sideroblastic anemia (due to impaired heme
(Vitamin H, Biotin, Growth Factor, Co-enzyme R)
It is 2-Imidazolidinone tetrahydrothiophene-4-valeric acid
Role of Vitamin B7
It is a co-enzyme for several carboxylation reactions.
Important for carbon dioxide fixation.
Important for Carbohydrates and Fats metabolism.
Co-factor for Pyruvate carboxylase.
• Only induced in experimental animals not observed in human:
• Skin lesions
• Retarded growth
• Hair loss
Daily ammount required:
100- 200 mg/day.
(Vitamin M, Vitamin B-c, Folic acid )
• Conjugate of Pteridine, p-Aminobenzoic acid and
CH2 NH C NH CH
p-Aminobenzoic acid Glutamic acid
Role of Vitamin B9
THF act as Co-enzyme for:
• Leucopoiesis (Production of Leukocytes).
• Erythropoiesis (Production of Erythrocytes).
• Nucleoprotein synthesis.
• Very rare due to:
• Malabsorption (due to alcoholism).
• Impaired Hepatic functions (due to alcoholism).
• Leads to:
• Glossitis (is inflammation or infection of the tongue ).
• Megaloblastic anemia
Daily ammount required:
0.1- 0.8 mg/day
Bacteria such as Streptomycin and Bacillus present in the intestinal
flora produce the vitamin required for man and animals.
The vitamin is stored in the liver with estimated t1/2 400 days.
B12 can be obtained from animal products only such as:
Promotes cell growth
Supports healthy immune
Promotes calcium absorption
Encourages good moods
Reduces the risk of flu
Reduces the risk of cancer
Reduces the risk of developing
Reduces the risk of
CHEMISTRY OF VITAMIN D
Vitamin D exists in two main forms, vitamin D3
(cholecalciferol) and vitamin D2 (ergocalciferol), differing in
their side chain structure.
VITAMIN D DERIVATIVES
Three vitamin D3 analogs are commonly used for the treatment of psoriasis:
calcitriol, calcipotriol and tacalcitol
DEFICIENCY OF VITAMIN D
vitamin D deficiency, putting at risk of bone problems, including rickets
in children and osteomalacia in adults, severe asthma in children,
Increased risk of death from cardiovascular disease, cancer.
Bone and calcium homeostasis
Diabetes & other conditions