Advance pharmacology-II, Mpharm (Pharmacology) 1st year, 1st semester

1. Advance Pharmacology - II
Topic:- Protective Activity
Of Certain Important
Antioxidant
Name :- Chetana Pandurang Dakhare
Roll No. :- 01 ( 2nd Semester )
First year M.Pharm (Pharmacology)

2. Antioxidant
• An antioxidant is a substances that when present in low
concentrations relative to the oxidizable substrate
significantly delays or reduces oxidation of the substrate
(Halliwell,1995).
• Antioxidants get their name because they combat
oxidation.
• They are substance that protect other chemicals of the
body from damaging oxidation reactions by reacting with
free radicals and other reactive oxygen species.

3. Antioxidant
• Antioxidant is a molecule capable of inhibiting the
oxidation of other molecules.
• Oxidation is a chemical reaction that transfer electrons or
hydrogen from a substance to an oxidizing agent.
• Eg: Hydroxyl radical, Superoxide anion radical, Singlet
oxygen, Hydrogen peroxide, Nitric oxide.

4. Antioxidants can be categorized by several
methods:
1) Types
a) Mode of action
b) Location
c) Solubility
2) Structural dependents
3) Origin

5. 1) According to types
Antioxidants
Non-
enzymatic
Nutrient: alpha
tocopherol, beta
carotene, ascorbate,
selenium
Non-nutrient
ceruloplasmin,
transferrin, uric acid.
Enzymatic
Superoxide dismutase,
glutathione peroxidase,
reductase, transferase,
catalase

6. • Mechanism of action:
• PREVENTIVE
• Enzymes: Superoxide dismutase, Catalase,
Glutathione.
• Metal ion sequestrators: Carotenoids,
Superoxide dismutase, Catalase, Glutathione,
Uric acid, Flavonoids.
• SCAVENGING
• Ascorbate, Carotenoids, Uric acid, a-tocopherol,
Flavonoids.

7. • Location:
• Intracellular :- SOD 1 and 2, Catalase,
Glutathione peroxidase, DNA repair enzymes.
• Extracellular :- SOD 3, reduced glutathione,
Ascorbate, Carotenoids, Uric acid.
• Membrane associated :- a-Tocopherol.

8. • 4) solubility
• Water soluble: Ascorbate, Uric acid, Thiols,
Flavonoids, Cysteine, Transferrin
• Lipid soluble: Alpha tocopherols, Carotenoids,
bilirubin.
• 5) structures they protect:
• DNA: SOD1&2, Glutathione peroxidase, DNA
repair enzymes, reduced glutathione,cysteine.
• Protein: Sequestration of transition metals by
preventive antioxidants.
• Lipid: Alpha tocopherols, Ascorbate, carotenoids,
glutathione

9. • 6) Origin:
• Exogenous: Carotenoids, Ascorbic acid,
Tocopherols, Polyphenols
• Endogenous: Catalase, Superoxide
dismutase, Glutathione

10. • Functions of Antioxidant:
• Antioxidant such as Vitamin-C and E boost our immune
system.
• Certain phytochemicals have beneficial effect on heart
disease.
• Antioxidant lowers the level of LDL-Cholesterol, thus
preventing plaque deposition in the blood vessel.
• Its beneficial in cancer prevention.
• Antioxidant neutralize substances that can damage the
genetic material by oxidation.

11. Major Group of Antioxidant" Metabolite
 Important group of antioxidant activity are
• Phenol
• Phenolic acid
• Anthocyanin
• Flavones
• Flavonoids
• Flavonols
• Tannins
• Isoflavanoids
• These group of compound shows antioxidant activity and
plant defence mechanism against microorganism

12. Major Antioxidant Compounds in Plants
• 1. Enzymes
1.1 Superoxide dismutase (SODs):
• SOD isoenzyme are present in chloroplasts, cytosol and
in mitochondria It catalyses the decomposition of
hydrogen peroxide into water and oxygen.
• 1.2 Glutathione: Participating directly in the
neutralisation of free radicals and reactive oxygen
compounds Maintaining of exogenous antioxidant such
as vitamin C & E in their reduced forms.
• 1.3 Glutathione Peroxide: Glutathione peroxide uses
glutathione as substrate and catalyses the reduction
ofhydrogen peroxide and lipid hydro peroxide

13. 2. Mineral:
• Minerals are elements that originate in the soil and can't
be created by living things.
• Selenium in the only mineral produced by plants. The
richest plants sources of selenium is Brazil nut.
3. Low Molecular Weight & High Molecular Weight
Compounds:
• HMW compounds includes albumin, cariplasmin and
transferrin.
• LMW antioxidant are divided into
• Lipid soluble:- Polyphenols, Tocopherols & ascorbic acid.
• Water soluble:- Same Polyphenols.
• Both types of these compounds act as reducing agents,
free radical scavengers quenchers of singlet
oxygen formation.

14. 4. Vitamins:
Carotenes:
• A carotene is one of four antioxidant that are
vital our general health and wellbeing.
• a-carotene,y-carotenes,6-carotenes and B-
carotenes types of carotenes
• a&B carotenes are the powerful antioxidant.
• B-carotene is an anti aging micronutrient and
play a significant role in reducing the effects of
certain illness such as heart disease, decreased
immune function, cataracts, cancer.

15. • Ascorbic acid (Vit-C):
• Its an hydrophilic antioxidant
• Neutralisation of H2O2
• Maintain healthy collagen in skin.
• Repair damaged tissue, healthy teeth and bones,
immune system.
• As a free radical fights against cataracts, arthritis, heart
disease, cancer & Oxidation.
• Vitamin C functions us anti-inflammatory and helps the
body fight against inflammatory diseases including
fibromyalgia, chronic fatigue, angina, bronchitis,
constipation and diabetes.
• Its also helpful in treating iron deficiency and anaemia.

16. Tocopherols (Vit-E)
• Vitamin E is primary fat-soluble antioxidant nutrient.
• Vitamin E resides in fatty tissues, especially cell walls and
membranes.
• It helps to protect the stability and integrity of cellular
tissues membranes throughout the body bypreventing
free radical (lipid peroxidation) damage.
It helps in
• Improving skin conditions
• Improving appearance of scars.
• Protecting the body's membrane.
• Maintaining healthy blood vessels.
• thinning blood in body

17. 5.Hormone as antioxidant:
• Melatonin:
• Its powerful antioxidant that can easily cross cell
membrane and the blood brain barrier.
• It doesn't undergo redox cycling.
• Melatonin cant be reduced its former state as it forms
stable compounds after reacting with free radical.
• It has been referred as a terminal or
suicidal antioxidant

18. 6. Essential Oils as Antioxidant:
• These are the class of volatile oils obtained by steam
distillation and these may be extracted from plants,
flowers, barks and seeds.
Advantages:
• Due to their small molecular size, they can easily
penetrate the skin tissue.
• As essential oils are lipid soluble they are capable of
penetrating the membrane easily even inn conditions
when oxygen deficiency present.
• They serve as powerful antioxidant & they prevent
mutants and oxidants in cells.

19. Biological role of Antioxidant:
• To counter the harmful effects of free radicals,
antioxidants defence mechanism operates to detoxify or
scavenge theses free radicals.
• Boost up immune system.
• Prevent the neurodegenerative disorder.
• Prevent DNA damage and there for have anticarcinogenic
effects.
• Promotes the cardiovascular health.
• Antioxidants can decrease LDL and cholesterol, Increases
HDL and blood pressure.
• Promotes the eye health and prevent macular
degeneration, cataract and other degenerative disorder.

20. Therapeutic uses of antioxidants:
• Alzheimer's disorder
• Cataract
• Diabetes
• Thrombosis
• Asthma
• Prevent the skin aging
• Parkinson's disease

21. THANK YOU