Phenolic antioxidants metabolism

Vaclavikova R, Horsky S, Simek P, et al. Paclitaxel metabolism in rat and human liver microsomes is inhibited by phenolic antioxidants. Naunyn-Schmiedelbergs Arch Pharmacol 2003 368 200-209. 

In addition, fhiit and vegetables can be minimally processed (washed, pealed, cut, diced, stripped, chopped, etc.) in order to provide ready to eat or ready to use products (salad mixes, apple slices, carrot sticks, diced potatoes, etc.). These minimal processing treatments damage the plant surface and induce changes in phenolic metabolism and phenolic antioxidant composition. 

Monohydric phenols Polyhydric phenols Phenolic acids Phenolic antioxidants Phenols and the environment Phenols and beverages Metabolic studies Clinical studies Phenolic resins... 

Duthie G and Crozier A (2000) Plant-derived phenolic antioxidants. Current Opinion in Clinical Nutrition and Metabolic Care 3 447-451. 

Phenol-induced oxidative stress mediated by thiol oxidation, antioxidant depletion, and enhanced free radical production plays a key role in the deleterious activities of certain phenols. In this mode of DNA damage, the phenol does not interact with DNA directly and the observed genotoxicity is caused by an indirect mechanism of action induced by ROS. A direct mode of phenol-induced genotoxicity involves covalent DNA adduction derived from electrophilic species of phenols produced by metabolic activation. Oxidative metabolism of phenols can generate quinone intermediates that react covalently with N-1,N of dG to form benzetheno-type adducts. Our laboratory has also recently shown that phenoxyl radicals can participate in direct radical addition reactions with C-8 of dG to form oxygen (O)-adducts. Because the metabolism of phenols can also generate C-adducts at C-8 of dG, a case can be made that phenoxyl radicals display ambident (O vs. C) electrophilicity in DNA adduction. 

I propose that by acting as antioxidants, phenolics can prevent and even cure these diseases by modulating the imbalance of metal metabolism. 

The impact of plant products on the metabolism of synthetic dmgs results from the inhibition or activation of cytochrome P-450 (CYP) enzymes. Evaluation of the potential activation of CYP by administration of natural plant products or dietary supplements is important for prediction of interactions between their components and dmgs. Therefore, attention is directed to research on the impact of products available on the food market known as natural non-nutritive substances on dmg absorption. Non-nutritive dietary components are mainly secondary plant metabolites, which include, among others, phenolic compounds such as phenolic acids and flavonoids. The health effects of non-nutritive substances are not yet known. So far, there is no answer on the extent to which they are absorbed and metabolized by the body, and there is no information on the permitted daily intake for these compounds. This information is particularly important because certain non-nutritive natural substances are simultaneously considered to be anti-nutritional factors, mainly because they inhibit digestion and reduce the bioavailability of nutrients or dmgs. It is also possible that they form undesirable interactions with dmgs. The positive health effects of non-nutritive natural substances are not only attributed to their antioxidant properties. These substances are involved in various metabolic... 

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