The document discusses antioxidants, which are agents used to prevent oxidation and rancidity in oils, fats, and pharmaceutical preparations. It includes classifications of antioxidants, ideal properties, and commonly used examples such as hypo phosphorous acid and sodium bisulphate. Additionally, it poses questions related to the definition and characteristics of antioxidants.

1. ANTIOXIDANTS
By
Saniya Shaikh
M. Pharm

2. ANTIOXIDANT
 The agents which are used to prevent oxidation are called as
antioxidants.
 Its is used to prevent rancidity of oils and fats.
 They prevent rancidity of oils and fats.
 They prevent deterioration of various pharmaceutical preparations
through oxidative processes.
 Antioxidants chemically acts as reducing agents.

3. CONTENT
 Introduction
 Classification of antioxidants
 Ideal properties of antioxidants
 Commonly used antioxidants
1. Hypo phosphorous acid
2. Sulphur dioxide
3. Sodium bisulphate
4. Sodium metabisulphite
5. Sodium thiosulphate
6. Nitrogen
7. Sodium nitrite
 Questions

4. CLASSIFICATION OF ANTIOXIDANTS
1. Quinol group : eg: tocopherols, hydroxyl coumarins.
2. Pyrogallol group : eg: amylgallate, n-propyl gallate.
3. Amines : eg. Cephalins, lecithin
4. Benzoic acid & derivatives : eg. Benzoic acid, esters of paramino
benzoic acid such as methyl paraben and propyl paraben.

5. IDEAL PROPERTIES OF ANTIOXIDANTS.
1. It should be stable
2. It should be effective in low concentration
3. It should not react with the preparation in which they are added
4. It should be compatible
5. It should be palatable
6. It should be neutral in nature.
7. It should be non toxic.
8. It should not produce any color or odor in the preparation.

6. COMMONLY USED ANTIOXIDANTS
1. Hypo phosphorous acid
2. Sulphur dioxide
3. Sodium bisulphate
4. Sodium metabisulphite
5. Sodium thiosulphate
6. Nitrogen
7. Sodium nitrite

7. HYPO PHOSPHOROUS ACID

10. SULPHUR DIOXIDE

12. SODIUM METABISULPHITE

14. SODIUM THIOSULPHATE

17. NITROGEN

19. SODIUM NITRITE

21. Sodium bisulphite

23. QUESTIONS
1. Define antioxidants
2. Give Natural sources of antioxidants
3. _________are the compound which inhibits the process of oxidation of
an ingredient in pharmaceutical preparation.
4. Molecular weight of SO2 is______
5. Sulphur dioxide is stable only in ______to ______acidic pH.
6. Sulphur dioxide has _______ and ________ properties.
7. Official sodium bisulphite is a mixture of ______ and_______ in
varying proportion.
8. Give the molecular formula of sodium thiosulphate.
9. give physical properties of sodium nitrite.
10. Give any one ideal properties of antioxidant.
11. Give 2 example of commonly used antioxidants.
12. Write any one use of nitrogen
13. Write the storage condition of sulphur dioxide