This document provides an overview of basic metabolic pathways in plants. It discusses primary and secondary metabolism, the role of enzymes and co-enzymes, and several key pathways such as the shikimic acid, acetate, and mevalonate pathways. Primary metabolites such as starch, cellulose, and chlorophyll are synthesized through basic metabolic pathways and are essential for plant growth and function. Secondary metabolites are derived from primary metabolites and have pharmacological activities. Enzymes help catalyze biochemical reactions in metabolic pathways, while co-enzymes assist enzymes and participate in reactions. Biosynthesis converts carbon dioxide into carbohydrates through photosynthesis.
Basic Metabolic Pathways and Their Role in Plant Secondary Metabolite Formation
1. BASIC METABOLIC PATHWAY
SEMESTER V
PHARMACOGNOSY AND PHYTOCHEMISTRY- II
UNIT- I
PRESENTED BY:
MISS. POOJA D. BHANDARE
ASSISTANT PROFESSOR
KANDHAR COLLEGE OF PHARMACY, NANDED
2. CONTENT
Overview of basic metabolic pathways
Role of Enzymes
Role of Co-enzymes
Shikimic acid pathways
Role of Shikimic aid pathway
Acetate pathways
The Mevalonate or Methylerythritol phosphate pathway
Amino acid pathway
Utilization of radioactive isotopes in the investigation of biogenetic diseases.
3. 1.1 Overview of basic metabolic pathways
METABOLIC PATHWAYS: A series of chemical reactions which
occur inside the cell. The reactants, products or the intermediates
which are formed as a result of these enzymatic reactions are called as
metabolites.
The reactant, product or the intermediates which are found as a result
of these enzymatic reaction.
These enzymes typically need dietary minerals, vitamins & different
co-factor.
4. There are two types of plant constituent obtained after
metabolism;
1. Primary plant metabolites
2. Secondary plant metabolites
5. Primary Plants Metabolism
These are considered as a basic plant constituents.
This are the simple in structure & they do not having any biological or
pharmacological activity associated with primary plant metabolites.
They also utilized by plants for building up their body & responsible for the
physiological functioning of the plant body.
Example :- Starch , chlorophyll, Calcium Oxalate crystals, cellulose, chelatin.
The pathways & chain of reaction through which the mention the compounds are
synthesized of produced in plants are know as basic metabolic pathway.
6. Primary metabolism
Degradation of carbohydrate and sugar generally proceeds via the
well characterized pathways know as glycoside and Krebs cycle/
Citric acid/ Tricarboxylic acid cycle.
Which is release the energy from the organic compounds by
oxidation reaction.
Oxidation of fatty acid from fats by sequence called Ɓ- Oxidation
that’s also provide energy.
7. Secondary Plant Metabolites
The secondary plant metabolites were biosynthesized from
primary plants metabolites which discussed in primary plant
metabolites.
Secondary plants metabolites are basically potent in their action
and then are associated with marked pharmacological actions on
human body.
These are also as active constituents determine the important role
in the process of biosynthesis.
10. Formation of Secondary Plant Metabolities
Secondary metabolites are not essential for growth and tend to be
strain specific.
They have wide range of chemical structures and biological activities.
They are derived by unique biosynthetic pathways from primary
metabolites and intermediates
Biochemical pathways that are not necessary for growth or
reproduction of organism, but which can be demonstrated genetically,
physiologically or biochemically.
11. Few important points of Primary and Secondary Metabolism
All organisms need to transform and interconvert a vast number of
organic compounds to enable them to live, grow and reproduce.
All organisms need to provide themselves with energy in the form of ATP,
and a supply of building blocks to construct their own tissues
An Integrated network of enzyme-mediated and carefully regulated
chemical reactions in used for this purpose, collectively referred to as
intermediary metabolism, and the pathways involved are termed
metabolic pathway.
12. Few important points Secondary Metabolism
Secondary metabolites are formed in only specific organisms, or
group of organisms, are expression of the individuality of species.
The compounds which synthesized from the secondary metabolism
are called as secondary metabolites.
Secondary metabolites are not necessarily produce under all
conditions, and in the vast majority of cases the function of these
compounds and their benefit to the organism is not yet know.
13. It is this area of secondary metabolism that provides most
of the pharmacologically active natural products.
Example :- Sugar, waxes, lignin starch, pigment, or
alkaloidal,
plants utilize very specific enzyme, each of which a specific
metaboloic reaction
These enzymes are proteins are called as organic catalysts.
14. The classes of secondary metabolites
The majority of secondary metabolites belongs to one of number of families, each of which
have particular structure characteristics arising from the way in which they are built up in
nature (biosynthesis)
The classes of secondary metabolites are
Polyketides and fatty acids
Terpenoids and steroids
Phenylpropanoids
Alkaloids
Others (Specialize amino acids and carbohydrate)
15. Role of Enzyme
Chemically, enzymes are protein in nature. These are colloidal
catalyst which help to increase the speed of biochemical reactions.
Sometime, only the speed of reaction is affected but it becomes
impossible for the plant to carry out the reactions in their body
They are very sensitive and active on specific temperature and pH
of the medium in which the reaction is carried out.
16. Classification of enzyme
1. Oxidoreductase: They involved in oxidation and reduction reactions. Example: glucose,
dehydroglucose, lyctase, peroxide.
2. Transferases: They transfer functional group (e.g., amino acid and phosphate groups). E.g.
Glucophosphorylase.
3. Hydrolases: They transfer water i.e they catalyze the hydrolysis of a substrate. E.g., Lipase,
chlorophilase, Amidase tannase and innulase.
4. Lyases: They add or remove elements of water, ammonia, carbondioxide to form double bonds.
5. Isomerases: They catalyze rearrangement of atoms within the molecule. For e.g., Maleate
isomerase
6. Ligases: They help to join molecule. For e.g., asparaginasr synthetase
17. Role of co-enzyme
Co-enzymes are organic molecule which are present in very small amount. Their
presence in small amounts.
Co-enzyme participate in the reaction in the same manner as the enzyme do.
e.g., Uridine phosphate and Adenosine phosphate contain nucleotide.
Some important Co-enzymes shoeing their effect in plant body as follows;
Uridine triphosphate, Thiamine, Pyridixine, Nicotinamide, Uridine diphosphate,
Rioflavin, Flavin etc
18. Biosynthesis:
Biosynthesis is one of the very important basic metabolic activities of the
plant through which the food material for the consumption of plant are
manufactured from the plant body.
In this process, photosynthesis, the carbon dioxide which is present in air is
converted into carbohydrate in the presence of sunlight.
Co2 + H2O CH2O + O2
Photosynthesis
Cholophyll