4-hydroxyphenylpropionic acid

The taxonomic application of the ability of enteric organisms to grow with 4-hydroxy-phenylacetate (Cooper and Skinner 1980) and 3-hydroxyphenylpropionic acid (Burlingame and Chapman 1983) has been established. In addition, it has been demonstrated that the enzyme that carries out the hydroxylation has a wide substrate range extending to 4-meth-ylphenol, and even to 4-chlorophenol (Prieto and Garcis 1994). 

Ward, N.C., Croft, K.D., Puddey, I.B., and Hodgson, J.M., Supplementation with grape seed polyphenols results in increased urinary excretion of 3-hydroxyphenylpropionic acid, an important metabolite of proanthocyanidins in humans, J. Agric. Food Chem., 52, 5545, 2004. 

Apart from glucuronic acid and sulfate conjugation of hydroxycoumarins, other phase II pathways of coumarin metabolism have been identified. For example, ortho-coumaric acid may be conjugated with glycine (Lake, 1999), and a coumarin mercapturic acid conjugate has also been reported (Huwer et al., 1991). Coumarin may also be metabolized by the gastrointestinal microflora to 3,4-dihydrocoumarin and ort/io-hydroxyphenylpropionic acid under anaerobic conditions (Scheline, 1968). 

Axidohydroxyphenylpropionic Acid. See under Hydroxyphenylpropionic Acid and Beil 10,... 

Chlorogenic acid has been used as a name for 5-O-caffeoylquinic acid by the authors of the reports cited except [Monteiro et al., 2007], 3-, 4-, or 5-CQA, 3-, 4-or 5-O-caffeoylquinic acid BA, benzoic acid CA, caffeic acid CLA, chlorogenic acid or 5-O-caffeoylquinic acid dHCA, dihydrocaffeic acid diCQA, dicaffeoylquinic acid FA, ferulic acid FQA, feruloylquinic acid GA, gallic acid HA, hippuric isoFA, isoferulic acid m-CA, ra-coumaric acid ra-HPPA, m-hydroxyphenylpropionic acid p-CA, p-coumaric acid p-HBA, p-hydroxybenzoic acid PPA, phenylpropionic acid. 

Griffiths LA. 1962. m-Hydroxyphenylpropionic acid, a major urinary metabolite of... 

As mentioned above, both the point-mutation on the distal side of the Mb and the modification of the heme-propionate side chains are effective to convert the Mb into peroxidase and peroxygenase. Thus, one can imagine that the combination of an amino acid mutation and a modified-heme reconstitution may more effectively allow us a new catalyst by oxygen storage. Recently, two examples, which demonstrated the hybrid modification of Mb, have been reported. One is the T67R/S92D Mb reconstituted with the modified hemin where a histidine is linked at the terminal of the heme-propionate side chain (108). The peroxidase activities toward p-hydroxyphenylpropionic acid and tyramine oxidations by the reconstituted mutant Mb are increased by 24- and 2.3-fold, respectively, based on the kciJKm value compared to those observed for the native Mb. 

Rump [17] has described a cellulose thin layer method for the detection of phenolic acids such as iw-hydroxybenzoic acid, iw-hydroxyphenylacetic acid and m-hydroxyphenylpropionic acid, in water samples suspected to be contaminated with liquid manure. The phenolic acid is extracted with ethyl acetate from a volume of acidified sample equalling lmg of oxygen consumed (measured with potassium permanganate). The ethyl acetate is evaporated and the residue dissolved in ethanol. After spotting of a lpm aliquot on a cellulose plate the chromatogram is developed by capillary ascent with the solvent n-propanol-w-butanol-25% NH3-water (4 4 1 1 by vol). The solvent front is allowed to advance 10cm. The air-dried plate is sprayed with a diazotised p-nitroanilinc reagent to make the phenolic acids visible. 

Figure 2. Ion chromatogram (inset) and electron ionization (70 eV) mass spectrum of hydroxyphenylpropionic acid shoving decomposition to the lactone (dihydrocoumarin).

Burman and Albertsson [116] have developed methods for quantifying certain theoretical degradation products of Irganox 1010 and Irgafos 168 from pharmaceutical solutions consisting of 10% ethanol in water. The degradation products of Irganox 1010 were 2,4-di-tert-butylphenol, 2,6-di-tert-butyl-p-benzoquinone, 3,5-di-tert-butyl-4-hydroxyphenylpropionic acid, 2,6-... 

Salicylic acid 5 a Methylhydroxybenzoic acid d Hydroxyphenylacetic acid e Hydroxyphenylpropionic acid e Hydroxyphenylbutyric acid e + + + + + +... 

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