W-Coumaric acid

Vanilloylglycine, feruloylglycine and /w-coumaric acid glucuronide are identified after oral administration of caffeic acid to humans [15], Intraperitoneal injection of the sodium salt of caffeic acid to rats also produces these conjugates. Thus, conjugation with glycine or glucuronic acid in body tissues is demonstrated. 

Hitro m-coumaric Acid, golden yel ndls (from ale), mp 248° 5-Nitro-m-coumaric Acid, crysts, having a taste not sweet, mp dec 6 Nitro w-coumaric Acid, micrcBC ndls (from ale), mp 216° and 3 NitrO p-coumaric Acid, col ndls (from w), yel ndls (from ale), mp 223° (dec) was prepd by heating 3 nitro-r-methoxycinnamic acid with an acetic acid soln of HBr for 3 hrs at 100°... 

P. Sathiyamoorthy, Identification of vanillic and p-coumaric acid as endogenous inhibitors of soybean seeds and their inhibitory effect on germination. J. Plant P/m-w/. /id 120 (1990). 

Price, W.P., Jr., and Deming, S.N. (1979), Optimized Separation of Scopoletin and Umbelliferone and cis-trans Isomers of Ferulic and p-Coumaric Acids by Reverse-Phase High-Performance Liquid Chromatography, Anal. Chim. Acta, 108, 227-231. 

Also, the phenolic compounds in olives have a strong influence on the flavor of the oil and seem to be responsible for the high oxidation resistance of olive oil. The phenolic content in the flesh of olive fruits ranges between 1% and 3%, w/w, (66) oleuropein, vanillic, caffeic, p-coumaric acid, rutin, luteolin-7-glucoside, heterosidic ester of caffeic acid, and hydroxytyrosol (verbascoside) have been identified in olive fruits. 

The impact of this loss upon insect growth has not been assessed, although considering Bernays findings (92,93), this approach may be useful for resistance. Double indemnity may accrue if the insect is toxified by cinnamic acid and coumaric acid. Unfortunately, these phenolics were not toxic to the noctuid Helio-this zea (M.B. Isman, S.S. Duffey and G.W. Felton, unpublished data). 

Salameh, D., Brandam, C., Medawar, W., Lteif, R., Strehaiano, P. (2007). Highlight on the problems generated by p-coumaric acid analysis in wine fermentations. Food Chem., (2007) doi 10.1016/j.foodchem.2007.09.052. 

The enhanced chemiluminescense obtained with the horseradish peroxidase-H202-luminol (139) system was applied to the development of a CLD biosensor for p-iodophenol, coumaric acid (26), 2-naphthol and hydrogen peroxide. The enzyme was immobilized by microencapsulation in a sol-gel matrix. LOD for the phenolic compounds were 0.83 p,M, 15 nM and 48 nM, respectively. A remote version of the enhanced biosensor was designed by directly immobilizing the enzyme on the tip of an optical fiber. This model was used for H2O2 assay. LOD was 52.2 p,M, with RSD 4.7% (w = 4) °. A bioluminescent response was obtained for phenols with pA a > 7 in the presence of a recombinant Escherichia coli strain, DPD2540, containing a fabA luxCDABE fusion this behavior may have analytical applications. 

The principal phenolic acids in these vegetables are ferulic and p-coumaric acid derivatives, the green parts of chives and leeks containing more than in the white part. In leek, the white tissue contains 6-7 mg ferulic acid per kg f.w., while this compound reaches concentrations of 23-39 mg/kg in the green parts [64]. In the case of chive, p-coumaric acid derivatives reach 21-51 mg/kg and ferulic acid derivatives 32-76 mg/kg. In garlic a different pattern of phenolic metabolite accumulation is observed in skins and internal tissues. The external tissues contain 49-58 mg/kg p-coumaric acid, 27-31 mg/kg ferulic acid and 27-25 mg/kg sinapic acid, whereas the internal tissues only contain 2mg, 6-8 mg and 2 mg/kg, respectively. In addition, the internal tissues contain 12-13 mg/kg p-hydroxybenzoic acid [64]. 

Protocatechuic acid is the main benzoic acid derivative in onions although jD-hydroxybenzoic acid and vanillic acid may also be observed [64]. In the outer dry coloured skins protocatechuic acid may represent up to 2% of plant material. The internal pulpy tissues show lower concentrations (ca 20 mg/kg f.w.). Unlike the bulbs, the green leaves of onions contain almost exclusively ferulic acid and jD-coumaric acid derivatives. 

KOJIMA, M., TAKEUCHI, W., Detection and Characterization of Para-Coumaric Acid Hydroxylase in Mung Bean, Vigna-Mungo, Seedlings, J. Biochem., 1989, 105, 265-270. 

Price, W.P. Denting, S.N. Optimized separation of scopo-letin and umbelUferone and cis-trans isomers of femlic and p-coumaric acids by reverse-phase high-performance Uquid chromatography. Anal. Chim. Acta 1979,108, 227-231. 

Hoff W.D., Dux, R, Hard, K., Devreese, B., Nugteren-Roodzant, I.M., Crielaard, W, Boelens, R., Kaptein, R., van Beeumen, J., and HeUingwerf K.J., Thiol ester-Unked p-coumaric acid as a new photoactive prosthetic group in a protein with rhodopsin-like photochemistry. Biochemistry, 33, 47, 13,959-13,962, 1994. 

Fig. 5.13. Gas chromatogram of silylated phenolic acids. Peaks 1 = p-hydroxybenzoic 2 = vanillic 3 = syringic 4 = p-coumaric 5 = ferulic 6 = sinapic acid 7 = n-docosane. Conditions glass column, 9 ft. X 1/4 in. O.D., 3% UCW-98 on Chromosorb W HP<100-120 mesh) nitrogen flow-rate, 40 ml/ min temperature programme, 6°C/min from 100°C. (Reproduced from J. Chromatogr., 71 (1972) 149, by courtesy of H. Morita.)...

In carrots, the principal phenolics are the hydroxycinnamic acid derivatives. Of these, caffeic acid derivatives are the main components (20-100 mg/kg fw. depending on the cultivar), while ferulic acid derivatives are accumulated in intermediate quantities (10-20 mg/kg) and p-coumaric derivatives, 4-hydroxybenzoic acid derivatives and vanillic acid are present in trace amounts [38]. The main compound in carrots is chlorogenic acid, which has been estimated as between 23 and 121 mg/kg f w. depending on the cultivar. However, in carrot tops, this compound can reach 375-400 mg/kg [40], while cryptochlorogenic, neochlorogenic and 5-feruloylquinic acids have also been detected. 

The phenolic compound content of the Cucurbitaceae is very low. Only trace amounts (3mg/ kg f w.) of neochlorogenic acid (3 -caffeoylquinic acid) were detected in one out of three zucchini (summer-squash) cultivars [40]. In an extensive study on the phenolic content of melons, watermelon, etc., only traces (ferulic acid were detected after hydrolysis. Very small antioxidant activity was reported for cucumber extracts [61], consistent with the very small phenolic compound content. However, the phenolic metabolism of melons is activated under environmental stress and wounding induces the phenylalanine ammonia lyase (PAL) gene [62]. 

Bell peppers, both green and red, contain low amounts of phenolic acid derivatives p-Coumaric (< 4 mg/kg), caffeic (< 10 mg/kg), ferulic (<15 mg/kg), sinapic (<5 mg/kg) and vanillic (10 mg/kg) acids [77]. Caffeoyl glucose, feruloyl glucose and sinapoyl glucose are the main hydroxycinnamic acid derivatives found, while no quinic acid derivatives have been detected [63]. Feruloyl glucose may accumulate up to 11 mg/kg f.w. and sinapoyl glucose up to 5 mg/kg in some red cultivars. 

As regards phenolic acid derivatives, potato tubers contain mainly caffeic acid derivatives, although ferulic, p-coumaric, sinapic and vanillic acids are also present [64]. The caffeic acid derivatives are mainly located in a thin 1-2 mm thick layer on the outer part of the tuber. The caffeic acid content ranges from 163 to 280 mg/kg f.w. depending on the cultivar. Ferulic acid (from 13 to 28 mg/kg), p-coumaric (from 0.5 to 4 mg/kg), sinapic (from 0.5 to 8 mg/kg) and vanillic acid (from 5 to 16 mg/kg) are present in much smaller amounts [64]. 

The leaves of Spinacia oleracea containp-coumaric (70-133 mg/kg f.w.) and ferulic acid (15-45 mg/kg) derivatives [38 64], of which p-coumaroyl-we o-tartaric acid is the main constituent (189-230 mg/kg). Feruloyl glucose (42-64 mg/kg), p-coumaroyl glucose (16-21 mg/kg) and p-coumaroyl malate (23-29 mg/kg) are also present in smaller amount [63]. 

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