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The degradation of functionalized arenes exposed to a mixed culture of chemoorganoaeroheterotrophic microorganisms has been shown to predominantly occur through oxidative intradiol decyclization of the aromatic ring. The spatial structure of the catalytic center of intradiol dioxygenase and its complexes with catechol and protocatechuic acid has been characterized using quantum chemical modeling procedures. The dependence of the total energy of the enzyme-substrate complex on the length of the bond between the iron atom and the hydroxyl group of the substrate (Fe-4-OH and Fe-1-OH) before and after the separation of water and a tyrosine residue (Tyr) from the catalytic center has been demonstrated for the first time.

Data for phenolic acids of two classes (hydroxybenzoic and hydroxycinnamic acids) occurrance and content in foodstuffs (fruits, berries, vegetables, species, cereals, tee, coffee and other beveradges) are reviewed. Data on their main dietary sourses are shown. Bioavailability and metabolism of phenolic asids and their derivatives are discussed.

Phenolic acids and flavonoids were characterized by cyclic voltammetry and total antioxidant activity in the reaction with the ABTS cation radical. Anode peak voltages (Eap) and their pH dependences were determined for the studied phenolic acids and flavonoids. The Eap and Trolox equivalent antioxidant capacity (TEAC) values were found to correlate for polyphenols, which react with the ABTS cation radical in two steps. Correlation between the half-wave potential (Ep/2) and TEAC was determined for electrochemically irreversible compounds. Mechanisms of the reaction of phenolics on the electrode involving one- and two-electron oxidation are proposed.