Simple phenolic compounds

Simple phenolic compounds include (1) the phenylpropanoids, trans-cinnamic acid, p-coumaric acid and their derivatives (2) the phenylpropanoid lactones called coumarins (Fig. 3.4) and (3) benzoic acid derivatives in which two carbons have been cleaved from the three carbon side chain (Fig. 3.2). More complex molecules are elaborated by additions to these basic carbon skeletons. For example, the addition of quinic acid to caffeic acid produces chlorogenic acid, which accumulates in cut lettuce and contributes to tissue browning (Fig. 3.5). 

StichHF. 1991. The beneficial and hazardous effects of simple phenolic compounds. Mutat Res 259 307-324. 

Murray, A. H., lason, G. R., and Stewart, C. (1996). Effect of simple phenolic compounds of heather [Calluna vulgaris) on rumen microbial activity in vitro. Journal ofChemical Ecology 22, 1493-1504. 

In contrast, both gas and liquid chromatography enable the samples of interest to be separated into individual components prior to introduction into the mass spectrometer ion source. Gas chromatography involves sample introduction with the requisite that the sample components must be volatilized prior to separation, and results in a gas sample being introduced to the mass spectrometer (i.e. El, Cl). Figure 5-2 shows the chromatogram obtained after a mixture of three simple phenolic compounds - phenol,... 

Edlin, D. A. N., Narbad, A., Dickinson, J. R., Uoyd, D. (1995) The biotransformation of simple phenolic-compounds by Brettanomyces anomalus. FEMS Microbiology Letters, 125, 311-315. 

Solvent systems were used as developers for simple phenolic compounds and some acids, which are products of lignin biodegradation... 

The appearance of simple phenolic compounds in water points to pollution stemming from industrial sources, such as manufacturers of dyes, drugs, antioxidants, pulp and paper, or may be the result of pesticide application. The presence of certain phenols in... 

Ogata N, Shibata T. 2000. Binding of alkyl- and alkoxy-substituted simple phenolic compounds to human serum proteins. Res Commun Mol Pathol Pharmacol 107(1-2) 167-173. 

An alternative or complimentary theory for the mode of action of simple phenolic compounds is that they are converted to much more toxic quinones. Pillinger et al. [69] found that various phenolic decomposition products of barley straw were most toxic under conditions favorable for oxidation of the compounds to quinones, and that quinones were up to one thousand-fold more toxic to algae than the parent compounds. The most likely route to conversion to a quinone is enzymatic. Peroxidases and polyphenol oxidases can perform such a reaction, depending on the substrate. However, polyphenol oxidase cannot be detected in most green algae [139] and has not been reported in cyanobacteria. 

Tanaka, T., Kojima, T., Suzui, M., and Mori, H., Chemoprevention of colon carcinogenesis by the natural product of a simple phenolic compound protocatechuic acid suppressing effects on tumor development and biomarkers expression of colon tumorigenesis. Cancer Res., 53, 3908-... 

The two most important aspen blue stain fungi are Ophiostoma crassivaginatum and O. piliferum. The secondary metabolites of the blue stain fungus O, crassivaginatum were studied in an attempt to obtain insight into the nature of the staining material. Several simple phenolic compounds were identified which, at least in part, can be responsible for the discoloration of aspen wood infected with this fungus (72). 

As observed in previous analyses, this model phase worked well for simple phenolic compounds. The correlation, r, between the measured and predicted molecular interaction energy values was more than 0.92 ( = 6) at pH 3-9. However, the molecular interaction energy values of larger compounds were smaller than expected. The reason for this is likely to be poor contact. 

Hydroxy acids are major aliphatic components of cutin and suberin and these are readily identified by GLC-mass spectrometry. Major ions generated from the usual cutin components are listed in Kolattukudy (1977). The position of the hydroxyl group in the chain is easily seen because cleavage occurs on either side of the substituent (Fig. 6.13). The rather simple phenolic compounds yielded by reductive depolymerization of cutin and suberin are also very... 

The simple phenolic compounds 5-ethyl-2-methoxy-phenol, phenol (74), guaiacol, and veratrole (33) (Fig. 8.8) have been proposed as sex pheromones for grasshoppers phenol (73), o-cresol, / -cresol (75), guaiacol, hydroquinone (76), catechol, p-benzoquinone, 4-methoxybenzaldehyde, 2,6,6-trimethylcyclohex-2-ene-l,4-dione, isophorone, and... 

Blum et al. [142] observed that effects of these simple phenolic compounds on cucumber leaf expansion were reversible, and that normal growth resumed upon removal of these compounds. Preconditioning plants with water stress or exposure to phenolic acids renders the plants less sensitive to the compounds [152]. The effects of these compounds are similar to those of water stress [14, 142, 153]. They can also inhibit ion uptake by plant roots [153]. There is some evidence that at least some of the effects... 

Flow injection methodology was used to estimate the total phenolic content of wine using acidic potassium permanganate chemiluminescence detection by Costin et al. (2003). Simple phenolic compounds such as quercetin, rutin, catechin, epicatechin, ferulic acid, caffeic acid, gallic acid, 4-hydroxycinnamic acid, and vanillin were examined analytically with chemiluminescence. Analysis of 12 different wines showed that detection limits were 2 x 10 M for caffeic acid, 3 x 10 M for ferulic acid, and 5 x 10 M for gallic acid. Comparison of the results of the chemiluminescence methodology and other total phenol/antioxidant assays showed that their correlation was good. Chemiluminescence... 

Ferulic acid in its free, conjugated, and bound forms is the most important simple phenolic compound present in cereal grains. It is a hydroxycinnamic acid associated... 

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