This power point provides brief view of secondary metabolites and their biosynthesis

1. Secondary
Metabolites
Lakshmi S
IInd M.Sc. Botany
1913392048003

2. Introduction
• Metabolites are the intermediates and products of metabolism, are typically characterized by
small molecules with various functions.
• Metabolites can be categorized into
1) Primary metabolites.
• A primary metabolite is directly involved in the normal growth, development, and reproduction.
• Examples:1.Carbohydrates 2.Proteins 3.Lipids 4.Nucleic acids
2) secondary metabolites.
• A secondary metabolite is not directly involved in those processes, but usually has important ecological function.
• Examples include antibiotics, mycotoxins etc.
• Secondary metabolites are derived from Primary metabolites

3. Terpenes

4. Terpenoids
• Terpenes constitute a large class of natural product built up from isoprene
units.
• Terpenes are technically only hydrocarbons while terpenoids are oxygenated
hydrocarbons.
• The basic molecular formula of terpenes are multiples of (𝐶5𝐻8)𝑛 where n is the
number of linked isoprene units(isoprene rule)
• Thus terpenoids are also called as isoprenoid compounds. One isoprene unit
is termed as hemiterpenes (𝐶5𝐻8)

5. Biosynthesis

6. Biosynthesis

7. Steroids

8. STEROIDS
• Steroids are compounds containing a cyclic steroid nucleus namely,
cyclopentanoperhydro phenanthrene (CPPP). It consist of a phenanthrene
nucleus (Ring A, B and C) to which a cyclopentane ring (D) is attached.
• There are several steroids in the biological system. These include Cholesterol,
Bile acids, Vitamin- D, Sex hormone, Adrenocortical Hormone, Sitosterol,
Cardiac glycosides and alkaloids. If the steroids contain one or more hydroxyl
group it is commonly known as sterol (means Solid alcohol)

9. BIOSYNTHESIS

10. Alkaloids

11. ALKALOIDS
• Alkaloids is defined as organic products of natural or synthetic origin which
are basic in nature and contain one or more nitrogen atoms, normally of
heterocyclic nature and posses specific physiological actions on human or
animal body, when used in small quantities

12. TYPES OF ALKALOIDS
• True alkaloids
• On basis of heterocyclic ring they are also known as Heterocyclic alkaloids
• They are toxic in nature
• They contain heterocyclic nitrogen which is derived from amino acids
• They are basic in nature
• Pseudo alkaloids
• They include mainly steroidal and terpenoid alkaloids and purines
• They are not derived from amino acids
• E.g. Conessine and caffeine
• Protoalkaloids
• They are known as biological amines or amino alkaloids
• They are simple amines in which nitrogen is not a heterocyclic ring
• E.g. Colchicine, Ephedine

13. TYPES

14. Quinone

15. • The quinones are a class of organic compounds that are formally "derived from
aromatic compounds [such as benzene or naphthalene] by conversion of an even
number of –CH= groups into –C(=O)– groups with any necessary rearrangement
of double bonds, resulting in "a fully conjugated cyclic-dione structure
• The archetypical member of the class is 1,4-benzoquinone or cyclohexadienedione,
often called simply "quinone" (thus the name of the class).
• Quinones are often readily made from reactive aromatic compounds with electron-
donating substituents such as phenols and catechols.
• Vitamin E acts as a scavenger and gets itself oxidized (to quinone form) by free
radicals (R)
QUINONE

16. QUININE AND QUINONE
• Quinone is (organic compound) any of a
class of aromatic compounds having two
carbonyl functional groups in the same six-
membered ring
• Quinine is (pharmaceutical drug) a bitter
colourless powder, an alkaloid derived
from cinchona bark, used to treat malaria
and as an ingredient of tonic water.

17. COMPOUNDS CONTAINING QUINONE
• Vitamin E
• Vitamin K
• Coenzymes
• Melanin

18. BIOSYNTHESIS
• Quinone biosynthesis is characterized by the diversity of the metabolic
pathways which allow the various living organisms to elaborate them from a
rather limited number of precursors: acetate and molonate, mevalonate, and
phenylalanine.
- Mevalonic and Chorismic Acid Pathway
- Polyketide Pathway
- 4-Hydroxybenzoic Acid Pathway

19. BIOSYNTHESIS

20. CHOLESTEROL
AND UBIQUINONE

21. Plant Phenols

22. PHENOLICS
• Phenolic are aromatic benzene ring compounds with one or more
hydroxyl groups produced by plants mainly for protection against stress.
• Broadly distributed in plant kingdom.
• Most abundant secondary metabolites of plants.
• Comprise 40% soluble protein of plants.
• More than 8000 structures of phenolics are known.
• Lignin(polyphenol) is second most abundant compound in plant.

23. SOURCES OF
PHENOLICS
• Fruits
• Vegetables
• Cereals
• Olive
• Legumes
• Chocolate
• Tea
• Coffee
• Wine

26. Anthocyanin

27. ANTHOCYANIN
• From the Greek antos: flower ; kyanos: blue
• They are a class of pigments belonging to a larger group known as
flavonoids, coming from a simple C6 – C3 – C6 structure of carbon rings.
• Have been used since antiquity as dyes, contributing to the coloration of
petals, fruits, bracts and leaves.
• They can be found in a variety of places in plants, depending on their
specific role.
• Often they appear in quite attractive colors, so they will oftentimes exist in
flowers and berries

28. ANTHOCYANIN
• Orange-red, red-blue colours
• Foods: strawberries, berries
(blueberries, cherries, blackberries),
grapes and some vegetables, such as
egg-plant and avocado.
• Water soluble – form, hydrogen bonds
with water due to the presence of
multiple hydroxyl groups.
• Natural acid-base indicators.

29. CHEMICAL STRUCTURE
• Three phenol groups (benzene ring) with
conjugated carbon-carbon bonds and
varying numbers of hydroxyl groups.
• Glucose molecules bond to the oxygen
atom on the second phenol group.
• Anthocyanins are found in foods high in
sugar content.
• What distinguishes anthocyanidins from
anthocyanins is the presence of sugars,
generally at the C-3 position (glycosides).

30. COLOUR VARIATION

31. ANTHOCYANIN IN
FRUITS
AND VEGETABLES

32. SYNTHESIS
• • Produced in response to light, whether it be visible, UV.
• • Production results from two synthesis pathways: acetate and
shikimic acid.
• • Acetate pathway produces 3 malonyl coenzyme A (CoA).
• • The shikimic acid pathway produces phenylalanine.
• • The two pathways combine to produce the base molecule, the
naringenin chalcone.

33. BIOSYNTHESIS

34. REFERANCE
• https://slidesharecdn.com/metabolites-181021112443/95/primary-and-secondary-
metabolites
• https://www.slideshare.net/Mona_Ismail/terpenoids-biosynthesis
• Pathfinder
• Biochemistry- Satyanarayana
• Slide Share- Maulik Patel
• Slide Share- Prakashsiju
• Schematic Scholar- Ubiquinone biosynthesis
• Research Gate- Phenol Classification

35. Thankyou
For listening