Phenols polyphenols

Both thermooxidation and photooxidation of polyolefins can be prevented by using the same antioxidants as those employed for the stabilization of polypropylene, ie, alkylated phenols, polyphenols, thioesters, and organic phosphites in the amount of 0.2—0.5% (22,25). 

The low specificity of electron-donating substrates is remarkable for laccases. These enzymes have high redox potential, making them able to oxidize a broad range of aromatic compounds (e.g. phenols, polyphenols, methoxy-substituted phenols, aromatic amines, benzenethiols) through the use of oxygen as electron acceptor. Other enzymatic reactions they catalyze include decarboxylations and demethylations [66]. 

FREE RADICALS, QUINONES, PHENOLS POLYPHENOLS, AROMATICS, ETC. 

In a polyphenolic extract, anthocyanins can interfere with other polyphenolics such as pro-cyanidins during HPLC analysis and hence should be removed prior to analysis. Anthocyanins from crude polyphenolic extracts can be removed as described in Basic Protocol 2. The ethyl acetate used for elution of phenolic compounds other than anthocyanins is removed using a rotary evaporator at 20°C. The non-anthocyanin polyphenolics are dissolved in deionized distilled water and the pH is adjusted to 7.0 with NaOH as described in Alternate Protocol 2 or the method developed by Oszmianski and Lee (1990a). In the latter method, polyphenolics were fractionated into three groups neutral fraction A (flavanols and other polar phenolics), neutral fraction B (flavonols), and acidic phenolics. Polyphenolic extracts were adjusted to pH 7.0 with NaOH... 

Crozier A, Jaganath IB, Clifford MN. 2006b. Phenols, polyphenols and tannins An overview. In Crozier A, Ashihara H, Clifford MN, Eds. Plant Secondary Metabolites and the Human Diet. Oxford Blackwell Publishing, PP. 1-31. 

Organic chemicals that are susceptible to oxidation and are of concern from the perspective of contamination and environmental degradation include aliphatic and aromatic hydrocarbons, alcohols, aldehydes, and ketones phenols, polyphenols, and hydroquinones sulfides (thiols) and sulfoxides nitriles, amines, and diamines nitrogen and sulfur heterocyclic compounds mono- and di-halogenated aliphatics linear alkybenzene-sulfonate and nonylphenol polyethoxylate surfactants and thiophosphate esters. Table... 

Lignin s decomposition in soil and sediment is accomplished primarily by white-rot and brown-rot fungi through enzymatically mediated mechanisms. Its decomposition produces an extremely diverse assemblage of phenols, polyphenols, and aromatic acids that are very reactive toward other NOM components and mineral surfaces (Nord, 1964 Martin and Haider, 1980 Wang et al., 1986). 

Keywords antioxidant phytochemical phenolic polyphenolic antioxidation plants... 

Coche-Guerente, L., Labbe, P., Mengeaud, V. (2001). Amplification of amperometric biosensor responses by electrochemical substrate recycling. 3. Theoretical and experimental study of the phenol-polyphenol oxidase system immobilized in Laponite hydrogels and layer-by-layer self-assembled structures. Anal. Chem. 73 3206-18. 

Polyphenols. Also called phenolic acids or phenolics, polyphenols are the parent class of several thousand compounds having similar chemical structure. Here is a list of the principal polyphenols to keep in mind for superfruits ... 

Cuzin, J.L., A. Testa, and S. Testa Die selektive Retention bestimmter chemischer Bestandteile des Kondensates Phenole, Polyphenole, heterocyclische Stickstoffverbindungen [Selective retention determined for chemical components of smoke condensate Phenols, polyphenols, and heterocyclic nitrogen compounds] Beitr. Tabakforsch. 3 (1965) 215-219. 

Testa, A., P. Testa, and J.L. Cuzin Observations on the specific retention of certain chemical constituents in the condensate (phenols, polyphenols, heterocyclic nitrogen compounds) CORESTA Sci. Comm. Mtg., Vienna, Austria (1964). 

Phenol, polyphenols, and cresols yield aromatic hydrocarbons on hydrogenolysis over nickel catalysts at temperatures above 250°C. 

Research into food safety, both microbial and chemical food safety, has been accompanied by a parallel effort to identify, test, and optimize healthy constituents of foods. The interest in chemicals in foods extends beyond traditional areas - vitamins, essential minerals, etc. - to secondary chemicals sometimes termed phytonutrients or neutraceuticals which have positive health benefits including prevention or alleviation of diabetes, heart disease, Alzheimer s disease, cancer, arthritis, and many other diseases. Food producers use this information as a marketing tool. Compounds of interest include phenols/polyphenols, flavonoids, carotenoids, anthocyanins, and several other classes that function as antioxidants,... 

Examples of Execution of Anticarcinogenic Action via Modulation of Intracellular Molecular Targets by Phenols, Polyphenols, Flavonoids, and OPCs... 

Olive pomace and olive pomace oil are natural by-products of olive oil production, which contain micro constituents with antithrombotic properties (Karantonis et al., 2008) and phenolic/polyphenolic molecules with antioxidant and other pleiotropic actions. Recent data from our research team reported for the first time that partial replacement of fish oil in gilthead sea bream grow-out diet by lipids obtained from olive pomace resulted in sufficient fish growth similar to the one of fish fed with 100% fish oil diet combined with improved antithrobotic properties of fish (Nasopoulou et al., 2011). 

Two plant oil sources, namely olive pomace and olive pomace oil were selected by our research team because of their content in athero-protective substances (such as PAF inhibitors) and phenolic/polyphenolic molecules (Karantonis et al., 2008), null cost since they are natural wastes of olive oil production, and fatty acid profile, which makes them likely candidates to partially substitute fish oil in compounded fish feeds. The reference diet (fish oil diet) contained 100% fish oil (cod liver oil) and its chemical composition is shown in Table 1, while the two experimental diets olive pomace and olive pomace oil diet were compounded by substituting 8% of fish oil of reference diet, respectively (Nasopoulou et al., 2011). 

Free radical scavengers are molecules that react with free radicals and render them harmless. There is considerable interest in foods rich in vitamins A, C and E (Chapters 51, 52 and 56) and those with an abundance of phytochemicals such as the phenols, polyphenols and flavonoids, which have high oxygen radical absorbance capacity (ORAC) values. These are potent free radical scavengers that are thought to reduce the risk of several chronic degenerative disorders. 

Crozier, A., Jaganath, LB. Cliford, M.N. (2006). Phenols, polyphenols and tannins An overview. In Plant Secondary Metabolites (eds A. Crozier, M.N. Clifford H. Ashihara), pp. 1-24. Blackwell, Oxford. 

Crozier, A., Jaganath, I.B., and M.N.C. 2006. Phenols, polyphenols and tannins an overview. In Plant secondary metabolites occurrence, structure and role in the human diet. Wiley-Black-well, Oxford U.K., 1-24. 

Dietary Phenolics, Polyphenolics, Tannins Structure and Human Metaboiism... 

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