E-Ferulic acid

Attachment of Hydroxycinnamic Acids to Structural Cell Wall Polymers. Peroxidase mediation may also result in binding the hydroxycinnamic acids to the plant cell wall polymers (66,67). For example, it was reported that peroxidases isolated from the cell walls of Pinus elliottii catalyze the formation of alkali-stable linkages between [2-14C] ferulic acid 1 and pine cell walls (66). Presumably this is a consequence of free-radical coupling of the phenoxy radical species (from ferulic acid 1) with other free-radical moieties on the lignin polymer. There is some additional indirect support for this hypothesis, since we have established that E-ferulic acid 1 is a good substrate for horseradish peroxidase with an apparent Km (77 /tM), which is approximately one fifth of that for E-coniferyl alcohol (400 /iM) (unpublished data). 

Angelica polymorpha Max. A. sinensis (Oliv.) Diels Dan Gui (root) Vitamin 12, vitamin E, ferulic acid, succinic acid, nicotinic acid, uracil, adenine, butylidenephalide, ligustilide, folinic acid, biotin, polysaccharide33 Treat irregular menstruation, anemia, thrombophlebitis, neuralgia, arthritis, chronic nephritis, constrictive aortitis, skin disease such as eczematous dermatitis. 

Tartaric acid Feruloyl (i.e., ferulic acid) 2,3-O-dicaffeoyltartaric acid (Cichoric Acid) R1, R2 = X 2-0-caffeoyl-3-0-feruloyltartaric acid R1 = X, R2 = Y 2-O-caffeoyltartaric acid (Caftaric acid) R1 = X, R2= H... 

Veratraldehyde 3 and veratric acid methyl ester 4 were isolated from vanillic aldehyde 5 and vanillic acid methyl ester 6 in the original reaction mixture. Silica gel chromatography of this reaction mixture was used to isolate small amounts of these primary oxidation products. These compounds had lost two carbon atoms from the origind propenoidic chain. A further component isolated from the methylated mixture was 2-methoxyhomoveratric aldehyde 7, which suggested the presence of 2-hydroxyhomoveratric aldehyde 8 in the oxidation reaction mixture. Its structure was confirmed by independent synthesis. Treatment of the reaction mixture from the catalytic oxidation of E-ferulic acid 1 with 1,3-dithiane followed by methylation formed the thioketal 9, which was also prepared by reaction of veratraldehyde 3 with 1,3-dithiane carbanion 10 followed by methylation. 

No reaction was observed in the absence of the catalyst. Moreover, Figure 1 shows that the conversion of E-Ferulic acid 1 was roughly linearly correlated to the concentration of the catalyst. 

Table L Product Yields % in the Reaction of E-Ferulic Acid 1 and E-Methyl Ferulate 11 with Co(II)salen-dioxygen. ...

Figure L The Dependence of the Conversion of E-Ferulic Acid 1 from the Catalytic Ratio R.

Conversion Studies The appropriate amount of catalyst was added to 50 mL of a 10"2 M solution of E-Ferulic acid 1 in methanol and the resulting solution was put in a 250 ml autoclave which was then charged with 10 bar of dioxygen. After 72 h at room temperature, the suspension was filtered and the solvent was evaporated under reduced pressure at room temperature. The residue was dissolved in 10 mL of methanol, methylated with excess ethereal diazomethane, filtered on a silica gel column and analyzed in GC using biphenyl as the internal standard. 

GRAF E (1992) Antioxidant potential of ferulic acid. Free Radical Biol Med, 13(4) 435-48. 

Maximal levels for -coumaric and ferulic acids of 30.0 and 6.5 pmol/1 0 g of soil ha e been reported (158) and concentrations of 4 x 10 M and 3 x 10 M, respectively, for these two acids in other soils (161)Other gtudies indicate a similar concentration range of 2.3 x 10 to 10 M for -hydroxybenzoic, vanillic and j>-coumaric acids (169). These levels may be too low to have direct measurable allelopathic effects on plants in greenhouse or growth chamber studies (non-rhizosphere soils, low microbial population). However, in field rhizosphere soils (high microbial population) these levels could be sufficient to influence microbial growth... 

A series of subsequent reactions after PAL first introduces a hydroxyl at the 4-position of the ring of cinnamic acid to form p- or 4-coumaric acid (i.e., 4-hydroxycinnamic acid). Addition of a second hydroxyl at the 3-position yields caffeic acid, whereas O-methylation of this hydroxyl group produces ferulic acid (see Fig. 3.3). Two additional enzymatic reactions are necessary to produce sinapic acid. These hy-drocinnamic acids are not found in significant amounts in plant tissue because they are rapidly converted to coenzyme A esters, or glucose esters. These activated intermediates form an important branch point because they can participate in a wide range of subsequent reactions. 

Phenolic acid A = ferulic acid phenolic acid B = caffeic acid flavonoid A = isoquercitrin flavonoid B = hyperoside phenolic acid E = chlorogenic acid flavonoid C = rutin. 

The amounts of the trans isomers of p-coumaric and ferulic acids were approximately ten times those of the corresponding cis isomers dehydrodiferulic acid occurred mainly as the trans, trans isomer. A major difference between cell walls of temperate (e.g., ryegrass, wheat) and sub-tropical (e.g., maize, Coastal bermudagrass) graminaceous plants is that the latter group contain comparatively large amounts of frans-p-coumaric acid... 

Incorporation of [1-13C] Ferulic Acid. [1-13C] ferulic acid 5a, synthesized as previously described (26), was administered for 21-28 days to seedlings of L. leucocephala and T. aestivum following germination. The solid state C-13 spectra so obtained are shown in Figs. 2a and 2b, respectively. Note that these are difference spectra, obtained by subtraction of natural abundance resonances from that of the C-13 enriched samples, i.e., only C-13 enhanced resonances are evident. 

The extent of inhibition of the oxidation of peroxidase substrates by ferulic salts was quite variable, from no inhibition to total inhibition. Total inhibition occurred when the substrate (e.g., syringaldazine) was closely related to ferulic acid. The presence of a fluorine atom in ferulic acid slightly reduced the inhibitory effect. Oxidation of ferulic compounds was restricted to lignifying cell walls in situ. Cell wall peroxidases from bark and xylem were fractionated into their component isozymes. 

Thus ferulic acid, which is not in vivo a natural substrate for peroxidases involved in lignification processes, can be oxidized not only in vitro but also in situ, i.e., in the normal, biological environment of the enzyme. Furthermore, the oxidation seems to be limited to the walls of lignifying cells. This restricted localization has been described only in the case of syringaldazine, a synthetic substrate closely related to cinnamic compounds... 

Enzymes attacking the non-glycosidic appendages of the heteroxylans include several recently discovered enzymes, i.e., acetyl-xylan esterase (42) and ferulic acid esterase (33), which are specific for the hydroly-... 

Oashi, H., E. Yamamoto, N. G. Lewis, and G. H. N. Towers. 5-Hydroxy-ferulic acid in Zea mays and Hordeum vulgare cell walls. Phytochemistry 1987 26(7) 1915-1916. 

Y. Maruta, and E. Nomura. Preparation of ferulic acid and its application... 

Odoux E, Chauwin A, Brillouet JM (2003) Purification and characterization of vanilla bean (Vanillaplanifolia Andrews) / -glucosidase. J Agric Food Chem 51 3168-3173 Overhage J, Steinbuechel A and Priefert H (2003) Highly efficient biotransformation of euge-nol to ferulic acid and further conversion to vanillin in recombinant strains of Escherichia coli. Appl Environ Microbiol 69 6569-6576... 

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