Download File

VITAMINS
VITAMINS
Introduction
Vitamins were discovered by Dutch physician, Christiaan Eijkmann, who
won the 1929 Nobel prize in physiology and medicine. The word vitamin
was derived from the term vitamine. The term "vitamine" was first used in
1912 by Dr. Casimir Funk, a Polish biochemist, in reference to substances
that were vital to life and contained an amine.
Vitamins are a group of organic food substances or nutrients found only in
living things, plants and animals.
Vitamins can be defined as naturally occuring organic substances which
are required in minute amount to maintain normal health of the organism.
Vitamins are vital nutrients which helps our internal organs to work
properly. We need vitamin in very small amount. Vitamins do not produce
any energy but is essential for maintaining our health.
Vitamins are nutrients that found in food like, cereals, lentils, fruits and
vegetables.
We need vitamins in very small amount and it helps in growth and for
maintaining our health.
Vitamins are necessary in small amounts for normal metabolism and good
health. Vitamins and minerals have no calories and are not an energy
source, but assist in metabolizing nutrients in food and are invaluable in
keeping your body running smoothly. Vitamins are sometimes referred to
as the "spark plugs" of our human machine.
FUNCTIONS OF VITAMINS





Vitamins promote normal growth, provide proper metabolism,
ensure good health and protect against certain diseases.
Vitamin is required by the body in small amounts for
metabolism, to protect health, and for proper growth in
children.
Vitamins assist in the formation of hormones, blood cells,
nervous-system chemicals, and genetic material
Vitamins combine with proteins to create metabolically active
enzymes that in turn produce hundreds of important chemical
reactions throughout the body.
Vitamins are responsible for keeping cells strong, binding
tissues, fighting infections, etc.
 Vitamins help regulate metabolism, help convert fat and

carbohydrates into energy, and assist in forming bone and
tissue.
Vitamin A plays an important role in vision, bone growth,
reproduction, cell division and differentiation.
CLASSIFICATION

Vitamins are divided into two classes based on their solubility.

The fat-soluble vitamins
vitamin A
vitamin D
vitamin E
vitamin K.

The water-soluble vitamins are
vitamin B12,
vitamin B6,
biotin,
niacin,
thiamin,
riboflavin,
pantothenic acid,
vitamin C (ascorbic acid)
DIFFERENCE BETWEEN FAT & WATER SOLUBLE
VITAMINS
Fat soluble vitamin


soluble in fat
require bile salt & fat for their
absorption.


generally stored in liver.

do not act as co-enzyme.
soluble in water.

Easily absorbed.

They

Not stored in body except
not excreted in urine.


Water soluble vitamin
vit.B12.

act as co-enzyme.

vit.B12 & vit.C
ex- A, D, E & K
VITAMIN A (RETINOL)

OCCURANCE-
Preformed vitamin A, or retinol, is found in:
Liver
Egg Yolk
Oily fish such as:

Herring
Pilchards
Tuna
Sardines
Whole Milk

.
Butter
Cheese
Good Sources of Beta Carotene include:
Carrots
Yellow and dark green leafy
vegetables (e.g. spinach,
broccoli, watercress)
Herbs such as:

Basil
Coriander
Parsley
Apricots
Pumpkin
Melon
Sweet Potatoes
Mango
Papaya
Red Pepper
Guava



Vitamin A is needed for new cell growth, healthy skin, hair, and tissues, and
vision in dim light.
Recommended dietary allowances : 900 µg
(male, age 19–70)
CHEMISTRY- IS DITERPENOID
STRUCTURALLY VIT. A IS CLOSELY RELATED TO
PLANT PIGMANT CAROTENE (C40H56) WHICH
EXIT IN DIFFERENT ISOMERIC FORMS.
CHEMISTRY
Retinol
Vitamin A is the collective name for a group of fat-soluble vitamins. The most
useable form of the vitamin is retinol, often called preformed vitamin A as it is
the active form in the body. Retinol (an alcohol) can only be found in animal
sources and can be converted by the body into retinal (an aldehyde) and retinoic
acid (a carboxylic acid), other active forms of vitamin A.
Beta Carotene
Beta carotene, a hydrocarbon, is one of a family of dark pigments called
provitamin A carotenoids, some of which can be converted to retinol by the
body. In the liver, one molecule of beta carotene can be cleaved by an intestinal
enzyme into molecules of retinol, so good food sources of beta carotene can
also be good sources of retinol. The conversion of carotenoids to retinol will
decrease when body stores are full thus preventing a retinol overdose, which
can lead to toxic symptoms.
Fig.1 The Chemical Structure of Retinol
Fig.2 The Chemical Structure of Beta Carotene
BIOLOGICAL FUNCTION
It plays important role on vision, growth and development. We need vitamin A
for maintenance of skin; hair and mucosal membrane of body .It also act as
antioxidant, which required for neutralizing free radicals found in body and
cause damage to body tissue

Vitamin A in the Body
Vitamin A is essential in the body for maintaining the immune system and
vision and alsoforgrowth and tissue differentiation. It is also thought to aid
prevention of cancer.

Vision
The retina of the eye is made up of light receptor cells, called rods, which allow
us to 'see' light and dark. Within these cells is a pigment called rhodopsin which
is a complex of opsin, a protein, and retinol. On exposure to light this complex
disintigrates and releases electrical charges to the brain via the optic nerve. New
rhodopsin is then formed from opsin and retinol.
. Immune System
Vitamin A aids health by maintaining the surface linings of the eyes and the
intestinal, respiratory and urinary tracts, thus preventing bacteria from
entering. It has also been suggested that vitamin A helps lymphocytes (a
type of white blood cell) to function effectively, and that carotenoids may
act as antioxidants in the body.
Tissue Differentiation


In the body there are many different cells with many different functions.
The process by which a cell becomes a specific type of cell is called
differentiation, and vitamin A is essential for differentiation of epithelial
cells (i.e those of the skin, the mucous membranes, the cornea and the blood
vessel walls).
DEFFICIENCY OF VIT. A

Deficiency of vitamin A can result in:
Night blindness - impaired vision in dim light.
Xerophthalmia - partial or total blindness due to
damage of the cornea from a severe deficiency.
Skin lesions.
Inhibited growth and bone development and loss
of weight in the young.
Increased susceptibility to infection.
Keratomalacia
an eye disorder that leads to a dry cornea. One of its
major causes is Vitamin A deficiency.
Overdose disease
Hypervitaminosis A
VITAMIN D (CALCIFEROL)

Vitamin D has two main forms:
D2 (ergocalciferol)
D3 (cholecalciferol).
Vitamin D is a fat-soluble vitamin which is obtained either
through the diet or simply by exposure to sun light. The
human body can produce Vitamin D; sunlight creates a
reaction producing vitamin D3 (cholecalciferol) which is then
converted by the liver and kidneys into biologically active
metabolites.
cholecalciferol
(Vitamin D3)
SOURCES:

Vitamin D sources:

Vitamin D is found in
milk (fortified), cheese, whole eggs, liver, salmon, and
fortified margarine.
The skin can synthesize vitamin D if exposed to enough
sunlight on a regular basis.
FUNCTION
Prevents Rickets ( a childhood disease) symptoms include malformed bones, bowed
legs, late tooth development, listlessness.
Regulates bone formation and repair.
VITAMIN E

Vitamin E:- ANTISTERILITY FACTOR
is a generic term for tocopherols and tocotrienols
Vitamin E is a family of α-, β-, γ-, and δ- (respectively:
alpha, beta, gamma, and delta) tocopherols and
corresponding four tocotrienols. Vitamin E is a fatsoluble antioxidant that stops the production of reactive
oxygen species formed when fat undergoes oxidation.
SOURCE
Excellent sources of vitamin E include
mustard greens, turnip greens,
chard, and sunflower seeds.

Very good sources of vitamin E include
almonds and spinach.

Good sources of vitamin E include
collard greens, parsley, kale,
papaya, olives, bell pepper, brussels
sprouts, kiwifruit, tomato, blueberries,
and broccoli.

Natural TOCOPHEROL exists as a mixture of 4
homologues, Alpha, Beta, Gamma, Delta - available as a
mixed product known as MIXED TOCOPHEROL which is also known as vitamin E. Riken Vitamin Co.,
Ltd. supplies TOCOPHEROL products and specialties
according to requirements by separating or combining
the homologues using unique technology.
Fig. 3The Chemical Structure of TOCOPHEROL
Homologues
R1
R2
R3
AlphaTOCOPHEROL
CH3
CH3
CH3
BetaTOCOPHEROL
CH3
H
CH3
GammaTOCOPHEROL
H
CH3
CH3
H
CH3
DeltaTOCOPHEROL
H