Antioxidants

1. WEL COME

2. Antioxidants Presented by G. Anvesh Kumar(M Pharm Pharmacology) 10 T 21 S 0103 . Under the guidance of Mrs. Geeta Reddy(Dept of Biotechnology )

3. An  antioxidant  is a molecule capable of inhibiting the oxidation of other molecules. Oxidation is a chemical reaction that transfers electrons or hydrogen from a substance to an oxidizing agent. Oxidation reactions can produce free radicals. In turn, these radicals can start chain reactions.

4. Types of Free   Radicals 1. Hydroxyl radical (OH•) 2. Superoxide anion radical (O2–•) 3. Singlet oxygen 4. Hydrogen peroxide 5. Lipid peroxyl free radical 6. Nitric oxide 7. Alkoxyl radical 8. Peroxynitrite

5. ROS Generation ROS Generation in the Mitochondria: Hydroxyl radical (OH•) Superoxide anion radical (O2–•) Non mitochondrial Generation of ROS: Hydrogen peroxide ROS are also introduced through external sources such as exposure to the sun or  pollution . Other mediums include stress, as well as things that people put into their bodies, such as alcoholic beverages, unhealthy foods, and cigarette smoke

6. Types of antioxidants: Mainly Hydrophilic and Hydrophobic Antioxidant enzymes:   1. Catalase 2. Glutathione peroxidase 3. Glutathione reductase 4. Super oxide dismutase (both Cu-Zn and Mn ) Metals binding proteins:   1 . Ceruloplasmin   2. Ferritin 3 . Lactoferrin   4. Metallotheinein 5. Transferrin   6. Hemoglobin 7.  Myoglobin

7. Common   antioxidants   (scavengers)   1. Bilirubin   2. Carotenoids a . Beta-carotene b . Alpha-carotene  c . Beta- cryptoxanthin d . Lutein   e . Zeaxanthin f . Lycopene   3 . Flavonoids a . Quercetin b . Rutin   c . Catechin 4 . Uric acids 5 . Thiols (R-SH)   6. Coenzyme Q10 7 . Vitamin A, C, E, D .   Others antioxidants   1. Copper  2.  glutathione  (GSH)  3. Alpha lipoic acid 4.Manganise 5. Selenium 6. Zinc

8. Mechanism of action of antioxidants Alpha tocopherol (vitamin E):   Prevent the peroxidation of membrane phospholipids, and avoids cell membrane damage through its antioxidant action Ascorbic acid (vitamin C) Scavenges free radicals and reactive oxygen molecules, which are produced during metabolic pathways of detoxification Ability to quench singlet oxygen, scavenge free radicals and protect the cell membrane lipids from the harmful effects of oxidative degradation . Beta Carotene

9. Superoxide dismutase (SOD) E liminating ROI by  reducing  (adding an electron to) superoxide to form H 2 O 2 . Catalase and the selenium-dependent glutathione peroxidase are responsible for reducing H 2 O 2  to   H 2 O . Catalase and glutathione peroxidase seek out hydrogen peroxide and convert it to water and diatomic oxygen. The catalase enzyme Glutathione peroxidase enzyme Glutathione peroxidase reduces H2O2 to H2O by oxidizing glutathione ( GSH)

10. Antioxidant System in our body Superoxide dismutase (SOD) Catalase Glutathione peroxidase The enzymatic antioxidants The nonenzymatic antioxidants Vitamins E, C, A or Provitamin A(beta-carotene), GSH

11. Pro-oxidant activities Antioxidants that are reducing agents can also act as pro-oxidants. For example, vitamin C has antioxidant activity when it reduces oxidizing substances such as hydrogen peroxide, however, it will also reduce metal ions that generate free radicals through the Fenton reaction . 2 Fe 3+  + Ascorbate → 2 Fe 2+  + Dehydroascorbate 2 Fe 2+  + 2 H 2 O 2  → 2 Fe 3+  + 2 OH ·  + 2 OH −

12. Determining Antioxidant Activity • ORAC, Oxygen Radical Absorbance Capacity method • TRAP, Total Radical-Trapping Antioxidant Parameter method. • TEAC, Trolox Equivalent Antioxidant Capacity method • DPPH • TOSC, Total Oxyradical Scavenging Capacity method • PSC, Peroxyl Radical Scavenging Capacity method • FRAP, Ferric Reducing/Antioxidant Power method.

13. Oxidative stress in disease: Oxidative stress is thought to contribute to the development of a wide range of diseases including Alzheimer's disease, Parkinson's disease, the pathologies caused by diabetes, rheumatoid arthritis, and  neurodegeneration  in motor neuron diseases How to measure the oxidative stress d-ROMs T This test is used to determine the antioxidant capacity of plasma, mainly due to the level of hydroperoxides - a subclass of reactive oxygen metabolites (ROM) - amplifiers and considered markers of cell damage by free radicals. BAP Test This test is used to determine the efficiency of the plasma barrier opposes the attack of free radicals in terms of iron-reducing activity An increase in the values of d-ROMs Test (> 300 U CARR) and / or a reduction of the values of the BAP Test (<2200 micromol / L) are indicative of a condition of oxidative stress 

14. Health effects: Disease treatment Disease prevention Physical exercise Adverse effects Benefits of antioxidants: Destroy the free radicals that damage cells. Promote the growth of healthy cells. Protect cells against premature, abnormal aging. Help fight age-related macular degeneration. Provide excellent support for the body ’ s immune system, making it an effective disease preventative. No Matter What Your Age…You Need Antioxidants!

15. Measurement and levels in food: Measurement of antioxidants is not a straightforward process, as this is a diverse group of compounds with different reactivities to different reactive oxygen species. In food science, the oxygen radical absorbance capacity (ORAC) has become the current industry standard for assessing antioxidant strength of whole foods, juices and food additives Antioxidants are found in varying amounts in foods such as vegetables, fruits, grain cereals, eggs, meat, legumes and nuts. Some antioxidants such as  lycopene  and ascorbic acid can be destroyed by long-term storage or prolonged cooking. Other antioxidant compounds are more stable, such as the polyphenolic antioxidants in foods such as whole-wheat cereals and tea. 

16. Antioxidant compounds Foods containing high levels of these antioxidants Vitamin C (ascorbic acid) Fresh  Fruits   and vegetables Vitamin E (tocopherols, tocotrienols) Vegetable oils Polyphenolic antioxidants ( resveratrol ,  flavonoids ) Tea,  coffee,  soy, fruit, olive oil,  chocolate, cinnamon,  oregano and  red wine Carotenoids ( lycopene , carotenes,  lutein ) Fruit, vegetables and eggs. Natural antioxidants

17. P ropylgallate(PG,E310), Tertiarybutylhydroquinone (TBHQ), B utylated hydroxyanisole  (BHA,E320) B utylated hydroxytoluene  (BHT, E321). synthetic antioxidants

18. The Color Code for Antioxidants: 1. Red – tomato, pink grapefruit, watermelon 2. Blue/Red/Purple/Black (BRPB) – blueberry, cherry, prune, blackberry 3. Orange/Yellow – carrot, pumpkin, orange, papaya 4. Green – broccoli, kale, spinach, pea 5. White – garlic, onion, cabbage, turnip 6. Brown/Gray – spices, nuts, seeds, endogenous sources How to Apply the Color Code 1.Enzymes (Brown/Gray) 2.Vitamins (Brown/Gray) 3.Phenolics (BRPB) 4.Carotenoids (Orange/Yellow, Red) 5.Hormones (Brown/Gray 6.Minerals (All colours ) 7.Glutathione (Brown/Gray) 8.Lipid effectors (Orange/Yellow) 9.Saponins, steroids and stilbenes (Green, BRPB) 10.Sulfur-containing chemicals (Green, White)

19. Uses in technology: Food preservatives Industrial uses

20. Conclusion Antioxidant plays an important role to prevent cancer, and other disease. They also have role in slowing ageing process and preventing  heart disease . So antioxidant are very much necessary for our body .But our body can’t manufacture these chemicals, so they must be supplied through diet.

21. ANY QUESTIONS