Biochemistry & Pharmacology: Open Access
Open Access
ISSN: 2167-0501
ISSN: 2167-0501
Nour Eddine ES-Safi
Accepted Abstracts: Biochem & Pharmacol
Polyphenols are natural substances which are recognized as one of the largest and most widespread class of plant constituents occurring throughout the plant kingdom. They are also found in substantial levels in commonly consumed fruits, vegetables and beverages. Polyphenols have aroused considerable interest because of their potential beneficial biochemical and antioxidant effects. These compounds show a great diversity of structures, ranging from rather simple molecules to polymers. Isolation and structural elucidation of polyphenols is very difficult because of their structural variability and reactivity. This is generally performed by a combination of chromatographic and spectroscopic methods, including ultraviolet, nuclear magnetic resonance and mass spectrometry. Polyphenols are also highly reactive compounds which undergo numerous enzymatic and chemical reactions during postharvest food storage and processing thus adding to the complexity of plant polyphenol composition. Although the occurrence of such reactions and their roles in food quality are well documented, the structures of the resulting products are still poorly understood and their concentrations in food are usually unknown. The purpose of this presentation is an overview of our findings concerning the isolation of natural antioxidants with special emphasis on polyphenols and the implication of the latters in food organoleptic properties and human health. The three following points will thus be presented and discussed: ? Isolation and identification of natural antioxidants ? Hemisynthesis and structure determination of derivatized monomeric and dimeric flavanols with investigation of their antioxidant properties ? Evolution of polyphenols in model solution systems and structure elucidation of the newly formed compounds