2. Carotenoids
Carotenoids are the fat soluble pigments
Carotenoids are lipids compounds range in
colour from yellow to purple .
They are nearly found in all the higher plants
There are two types of carotenoids
• Carotenes
• Xanthophyll's
3. Carotenes
• These are pure hydrocarbon composed of eight same
elements.
• The term carotene is basically used for the
unsaturated hydrocarbons substances.
• They are mainly synthesized in the plant.
• These can not be synthesized in the animals except
spiders and aphids.
• These animals gets the genes from the fungi .
4. Function of the Carotenes
There are following functions of the carotenes
• Carotenes are responsible for the orange colour of the
carrot.
• They are responsible for the colour of many fruits and
vegetables.
• They are also responsible for the orange color of the dry
foliage.
• They also give the yellow coloration to the milk and butter.
5. Production of the Carotenes
There are two methods of the productions of the
carotenes artificially
• Witting reaction
• Grignard reaction
6. Food Additive’s
• Carotenes is also used as a substance to colour the
products as juices , cakes deserts, butter and
margarine.
• It is approved as the food additive in the EU and
New Zealand.
7. Carotenes is present in
• Carotenes are present in the palm oil, in the corn ,
in the milk , of the dairy cows and the yellow
color of the milk depend upon the feed of the cow
and amount of the fat in the milk.
• Carotenes is also present in some species of the
termites where they are apparently picked up by
the diet of the insects.
8. Xanthophyll's
• These are oxygen containing hydrocarbons.
• These are the yellow pigments.
• These widely occur in the nature.
• The word xanthophyll is derived from the Greek word
xanthose and phyllon due to the formation of the
yellow bands seen in the chromatography of the plant
pigments.
9. Presence of Xanthophyll's
• Xanthophyll's are present in highest quantity in the
leaves of the green plants.
• There act to modulate the light.
• It also act as a non photochemical quenching agent to
deal with the triplet chlorophyll which is produced in
the high quantity in the photosynthesis.
• They are also found in the bodies of the animals and
human and in the dietary animal products which are
derived from the plant source in the diet.
10. Difference between Xanthophyll's &
Carotenes
• As both the xanthophyll's and carotenes are
similar in the structure.
• But the xanthophyll's contains the oxygen atoms.
• The carotenes have no oxygen atoms.
11. Collective function of the Carotenoids
• The carotenoids are embedded in the protein by the non covalent bond.
• The carotenoids play two important role in the plants.
• They protect the photosynthetic member against the damage by the light
and by the large amount of the energy which is absorbed by them.
• They absorb the light energy and transfer it to the chlorophyll a.
• Therefore they are also called the accessory pigments.
• They also play important role in determining the parameters of the fruits
and vegetables.
12. • The carotenoids are responsible for the yellow orange , and
red hues of the fruits and flowers.
• They are also responsible for the colour of the many birds.
• They are also responsible for the colour of the fishes
crustaceans and insects.
• They are partially responsible for the fall coloration after
the leaf chlorophyll has been destroyed.
• Animals are unable to synthesize the carotenoids.
13. Classification
Carotenoids are classified into two types
• The hydrocarbon without oxygen which are
called carotenes.
• The oxygenated carotenoids which are known
as the xanthophyll's.
14. Structure
• Carotenoids are lipid soluble c40 tetrapenoids.
• The majority of the carotenoids are derived from the
40 Carbon polyene chain.
• Which could be considered as the backbone of the
molecule.
• This chain may be terminated as the cyclic end group
or can be terminated by a oxygen containing
functional group.
15. Other Examples of Carotenoids
These are following examples
• Antheraxanthine
• This is present in the plants especially in the maize
• Astaxanthine
• Present in the salmon shrimp and lobsters
• Canthaxanthine
• Present in the flamingo feathers
