94236 - Chemistry of Antioxidants

Learning outcomes

At the end of the course students will be familiar with the radical reactions involved in the oxidation of organic materials and on the main mechanisms for antioxidant protection. The student will know the main classes of natural and synthetic antioxidants and the structure-activity relationships for antioxidant behavior. He/She will have developed a critical attitude in the evaluation of a potential antioxidant. The student will know the main methods to test the antioxidant activity in model systems, either chemical or biomimetic.

Course contents

1) Structure and properties of free radicals. Stability of radicals, BDE. Main radical reactions and radical species involved.

2) Reaction of auto-oxidation. Initiation (photochemistry, thermal, redox), propagation (HAT, addition), termination. Non-radical reactions of hydroperoxides. Oxidation of biological molecules and drugs.

3) Antioxidants. General characteristics and mechanisms of action (preventive and chain-breaking). Phenols as antioxidants, phenoxy radicals. BDE of the phenolic bond. Kinetic aspects of autoxidation inhibited by phenols. Constant of inhibition. Catalytic antioxidants (aromatic amines, nitroxides). Natural and synthetic antioxidants.

4) Measure the antioxidant activity. Methods based on inhibited autoxidation: measurement of O2 consumption, peroxide formation, conjugated dienes, consumption of oxidizable probes. Approximate methods: ORAC, DPPH, ABTS.

5) EPR spectroscopy. Mechanism of operation and interpretation of the spectra. Spin trap.

6) Oxidative stress in biological systems. Natural antioxidant defenses. Ferroptosis.

Readings/Bibliography

Lecture notes and material uploaded to Virtual.

Teaching methods

The lectures will involve the use power-point presentations. Problem solving sessions will be carried out for the student to gain acquaintance with the numeric treatment of chemical problems.

Assessment methods

The learning assessment takes place through a final exam, in which the acquisition of the knowledge and the expected abilities is verified by an oral exam.

Teaching tools

Multimedia material will be presented, such as slides, movies, animations and three-dimensional visualization of atoms, molecules and materials. Software that allow to view biological macromolecules in 3D will be used.

The multimedial material utilized during the lectures will be made available for download from the teacher's web site.

Students are asked to report any needs to the teacher via private mail. This will allow the teacher to evaluate which teaching support tools are most adequate to make the course accessible to all students.

Office hours

See the website of Riccardo Amorati