This book presents information about the high enzymatic reactivity of reactive oxygen species. Chapters in the book cover several aspects of the topic such as the sources, formation mechanisms, reaction centers, oxidation-reduction reactions, cellular respiration chemistry, enzymatic kinetics, mitochondrial and plastid electron transport chains, oxidation-reduction potential, reaction constants, reaction velocity and reaction mechanisms involved, cellular cytotoxicity, antioxidant defense mechanisms in plants and animals, response of plants to conditions of environmental stress, xenobiotics, and the thermodynamics inherent to oxygen metabolism. The book also features a chapter on flavonoids which highlights a paradoxical facet of the affinity of reactive oxygen species for enzymes.
Flavonoids are mainly antioxidant molecules as they act as trappers of reactive oxygen species. The chapter informs readers about the metabolic pathways mediated by enzymes through wich flavonoids become promoters of these same reactive oxygen species. All chapters present the subject in a simple, analytical format, while highlighting the scientific evidence gathered by researchers so far. The volume is an interesting reference for scholars learning about the biochemistry and enzymology of oxygen and its free radical derivatives.
Flavonoids are mainly antioxidant molecules as they act as trappers of reactive oxygen species. The chapter informs readers about the metabolic pathways mediated by enzymes through wich flavonoids become promoters of these same reactive oxygen species. All chapters present the subject in a simple, analytical format, while highlighting the scientific evidence gathered by researchers so far. The volume is an interesting reference for scholars learning about the biochemistry and enzymology of oxygen and its free radical derivatives.
Table of Contents
Chapter 1 Oxygen- Introduction
1. Nature
1.2. Oxygen Free Radicals
1.2.1. Reactive Oxygen Species (Ros)
1.2.2. Reactions Of Reactive Oxygen Species In Aqueous Environments
1.2.3. Fenton Reaction
1.3. Cytotoxicity Of Reactive Oxygen Species (Ros)
1.3.1. Superoxide
1.3.2. Hydrogen Peroxide
1.3.3. Hydroxyl Radical
1.3.4. Ros Damage To Macromolecules
- Conclusion
- References
Chapter 2 Biological Oxidation
- Introduction
1. Redox Potential
1.1. Oxidases
1.2. Nadh Dehydrogenase
1.3. Hydroperoxidases
1.4. Oxygenases
2. Mitochondrial Electron Transport Chain
- Conclusion
- References
Chapter 3 Reactive Oxygen Species Sources
1. Endogenous Sources
1.1. Enzymes
1.1.1. Cytochrome C - Enzymatic Oxidation
1.1.2. Xanthine Oxidase (Xo) -Reaction Center
1.1.3. Xanthine Oxidoreductase (Xor)
1.1.4. Galactose Oxidase
1.2. Cells And Organelles
1.2.1. Phagocytic Cells
1.2.2. Peroxysomes
1.2.3. Mitochondria
1.2.4. Microsomes
1.3. Cytosolic Molecules
2. Exogenous Sources
2.1. Haber - Weiss Reactions
2.2. Iron
2.2.1. Iron Storage Proteins
2.3. Copper
2.4. Chrome
2.5. Cadmium
2.6. Vanadium
2.7. Mercury
2.8. Nickel
2.9. Zinc
2.10. Lead
2.11. Cobalt
2.12. Xenobiotics. Paraquat - Pq
- Conclusion
- References
Chapter 4 Antioxidant Defense Systems
- Introduction
1. Primary Antioxidant Defense Systems
1.1. Enzymes
1.1.1. Superoxide Dismutase-Sod
1.1.2. Catalase
1.1.3. Selenium-Dependent Glutathione Peroxidase
1.1.4. Glutathione Reductase
1.1.5. Glucose-6-Phosphate Dehydrogenase
1.1.6. Other Enzymes
1.2. Antioxidant Mitochondrial Defense
1.2.1. Mitochondrial Coenzyme Q. Ubiquinone
1.3. Non-Enzymatic Traps
1.3.1. Proteins
1.3.2. Glutathione
1.3.3. Vitamin C
2. Secondary Antioxidant Defense Systems
2.1. Enzymes
2.1.1. Protein-Specific Oxidoreductases
2.1.2. Proteases
2.1.3. Glutathione Peroxidase Not Dependent On Selenium
2.1.4. Phospholipases
2.2. Non-Enzymatic Traps
2.2.1. Vitamin E
2.2.2. Carotenoids
3. Antioxidant Plant Defense Systems
- Conclusion
- References
Chapter 5 Flavonoids As Reactive Oxygen Species Promotors
- Introduction
1. Flavonoid Chemical Structure
2. Types And Sources Of Flavonoids
3. Flavonoids As Trapping Agents For Reactive Oxygen Species -Ros.
3.1. Structure-Function Relationship
3.1.1. Flavonoids As Antioxidants
3.2. Redox Chemistry
4. Mechanisms Of Flavonoid Antioxidant Activity
4.1. Position And Number Of Groups Oh
4.2. Formation Heat Of Flavonoid Radicals (∆Hf)
4.3. Bond Dissociation Energy (Bde) And Ionization Potential (Ip)
4.3.1. Quercetin
4.3.2. Rutin
4.4. Chelation Of Metallic Ions
5. Inhibition Of Prooxidant Enzymes Mechanisms
5.1. Xanthine Oxidase
5.2. Lipoxygenase
6. Measurement Methods For Flavonoid Antioxidant Activity
7. Some Techniques Utilized To Determine The Bioavailability Of
- Flavonoids
8. Reactive Oxygen Species Measurement
9. Intestinal Absorption And Plasma Levels Of Flavonoids
10. Flavonoids Prooxidant Activity Mechanism
- Conclusion
- References
Chapter 6 Oxygen Availability
1. Reactive Oxygen Species-Ros In Hypoxia
- Conclusion
- References
- Subject Index
Author
- Carmen Cecilia Espíndola Díaz
