5-Hydroxy-ferulic acid

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. 

Cinnamic acid and Hydroxy cinnamic acids. The biosynthetic sequence cinnamic acid —> p-coumaric acid caffeic acid —> ferulic acid — 5-hydroxy-ferulic acid -> sinapic acid (Eig. 6.3) includes progressive hydroxylation at the... 

Trihydroxy - cinnamic acid 5-Hydroxy ferulic acid... 

Cinnamic acid, 4-hydroxy- ferulic acid 54. Propanoic acid, 3-hydroxyphenyl- ... 

Recent scientific investigations of natural polyphenols have demonstrated their powerful antioxidant property (Niki et al, 1995). Several classes of polyphenols have been chemically identified. Some of these are grape polyphenols, tea polyphenols, soy polyphenols, oligomeric proanthocyanidines (OPA) and other natural polyphenols of the flavone class. Rice bran polyphenols are different from the above in that they are p-hydroxy cinnamic acid derivatives such as p-coumaric acid, ferulic acid and p-sinapic acid. Tricin, a flavone derivative, has also been isolated from rice bran. 

Bioassay for Toxicity of Inhibitory Compound(s). Since the identity of the inhibitory compound was determined to be ferulic acid (4-hydroxy-3-methoxycinnamic acid), ferulic acid obtained from Sigma Chemical Company was used in germination bioassays. 

With the extraction procedure we employed (22), ferulic acid was isolated as the most inhibitory component in wheat straw. There could also be other unknown compounds in the straw which would not be evident with this procedure. In addition, we ignored the possible influence of toxin-producing microorganisms. Microorganisms may have influenced the phytotoxicity exhibited by the aqueous wheat extract in Table IX. Although the present study was not concerned with the phytotoxic effects of microbially decomposed wheat straw, an influence of microbial activity on ferulic acid phytotoxicity was observed. From the results shown in Table XI, it appears that the presence of the prickly sida seed carpel enhanced the inhibitory effects of ferulic acid. In addition to ferulic acid in test solutions containing prickly sida seeds with carpels, a second compound, 4-hydroxy-3-methoxy styrene, was also found to be present. This compound is formed by the decarboxylation of ferulic acid and was produced by a bacterium present on the carpel of prickly sida seed. The decarboxylation of ferulic acid was detected in aqueous solutions of ferulic acid inoculated with the bacterium isolated from the carpels of prickly sida seed. No conversion occurred when the bacterium was not present. 

How the aliphatic monomers are incorporated into the suberin polymer is not known. Presumably, activated co-hydroxy acids and dicarboxylic acids are ester-ified to the hydroxyl groups as found in cutin biosynthesis. The long chain fatty alcohols might be incorporated into suberin via esterification with phenylpro-panoic acids such as ferulic acid, followed by peroxidase-catalyzed polymerization of the phenolic derivative. This suggestion is based on the finding that ferulic acid esters of very long chain fatty alcohols are frequently found in sub-erin-associated waxes. The recently cloned hydroxycinnamoyl-CoA tyramine N-(hydroxycinnamoyl) transferase [77] may produce a tyramide derivative of the phenolic compound that may then be incorporated into the polymer by a peroxidase. The glycerol triester composed of a fatty acid, caffeic acid and a>-hydroxy acid found in the suberin associated wax [40] may also be incorporated into the polymer by a peroxidase. 

Hydroxy cinnamic acids are included in the phenylpropanoid group (C6-C3). They are formed with an aromatic ring and a three-carbon chain. There are four basic structures the coumaric acids, caffeic acids, ferulic acids, and sinapic acids. In nature, they are usually associated with other compounds such as chlorogenic acid, which is the link between caffeic acid and quinic acid. 

The important conclusion is that much of the wall s ferulic acid is linked to specific hydroxy groups on specific sugars of specific polysaccharides. The specificity is particularly notable in the case of Fer-Ara2, since the feruloylated arabinose residues are in the rare pyranose ring-form (17). It is clear that the feruloylation reactions are not random, but are carefully steered biosynthetic steps. 

Ferulic acid 4-Hydroxy-3-methoxy-cinnamic acid... 

Non-ruminants possess several intestinal Na+-dependent saturable transport systems. These include the well-known sodium-glucose co-transporter (SGLT1), responsible for the active uptake of glucose, and it appears to be specific for cinnamic and ferulic acid and possibly for other hydroxy-cinammic acids [112]. 

Hydroxy-3-methoxycinnamic acid (ferulic acid) [] 35-24-6] M 194.2, m 174 . Crystd from H2O. 

Some monocot, primary cell-wall polysaccharides may be cross-linked by esters of ferulic acid (4-hydroxy-3-methoxycinnamic acid). There is evidence for the existence of such cross-links in monocot tissues containing secondary walls, including Italia ryegrass stem276 and wheat endosperm.277 Ferulic acid is also present in barley cell-wall,278 and it has been reported that treatment with base releases ferulic acid from the cell walls of several Graminae,276 supporting the idea that ferulic acid is bound to the wall as an ester. However, ferulic acid has not, so far, been reported to be present specifically in primary cell-walls in either monocots or dicots. 

After oral administration of caffeic acid to rats, small amounts of vanillic acid and vanilloylglycine are excreted. The conversion of p-hydroxycinnamic acid into /7-hydroxybenzoic acid is found in rat liver mitochondria [18], Studies with /7-hydroxy[U-14C]cinnamic acid have showed that 14C02 is released during reaction, indicating that reaction probably followed the p-oxidation type reactions, the two carbon being first removed as acetyl-CoA, and then oxidized to C02. It is assumed that conversion of ferulic acid formed by methylation of caffeic acid into vanillic acid occurs in rat liver mitochondria. 

Both the free and the combined forms of phenolic acids in date fruit (Phoenix dactylifera L.) were analyzed by HPLC (19). The elution rate of phenolic acids increased with the degree of hydroxylation by isocratic elution using dioxane-acetic acid (15 85) on a /zBondapak C,8 column. Ferulic acid was the most abundant in the free form, and p-coumaric, vanillic, p-hydroxy-benzoic, protocatechuic, and syringic acid were also identified in dates. 

Synthesis of podophyllotoxin (3.86) in cell culture of Linum album results in yields comparable to those of the most efficient tissue cultures of Podophyllum hexandrum. In order to further improve L. album cultures, Seidel et al. (2002) investigated the biosynthesis of podophyllotoxin (3.86). They fed a number of labeled compounds that to L. album cell cultures to identify which of these compounds could be used as precursors to podophyllotoxin. They determined that the substitution pattern on the benzene ring is critical. The substitution has to be either 3-methoxy, 4-hydroxy, as in ferulic acid (3.33), or, alternatively, 3,4-methylenedioxycinnamic acid (3.90) can serve as precursor. The precursor of podophyllotoxin in L. album appears to be deoxypodophyllotoxin (3.83), based on the higher level of isotope incorporation in the latter compound. This means that 7-hydroxymatairesinol, the precursors of 5-methoxypodophyllotoxin in L. flavum (Xia et al., 2000), is not a precursor of podophyllotoxin in L. album. 

Suberins or polyestolides are related to cutins. These are complex polymers composed of co-hydroxy monobasic acids linked by ester bonds. They also contain a,P-dibasic acids esterified with diols, as well as ferulic and sinapic acid moieties. Suberins are enriched with molecules having 16 and 18 carbon atoms. They also have ethyl-enic and hydroxyl functionalities, and ester and ether cross-linking can occur. 

Abresoline on basic hydrolysis gave /rans-4-hydroxy-3-methoxycinnamic acid (ferulic acid) and the quinolizidol (63a). The presence of these units was also apparent in the mass spectrum of the alkaloid which showed strong... 

The phenolic acids of interest here [caffeic acid (3,4-dihydroxycinnamic acid), ferulic acid (4-hydroxy-3-methoxycinnamic acid), p-coumaric acid (p-hydroxycinnamic acid), protocatechuic acid (3,4-dihydroxybenzoic acid), sinapic acid (3,5-dimethoxy-4-hydroxyxinnamic acid), p-hydroxybenzoic acid, syringic acid (4-hydroxy-3,5-methoxybenzoic acid), and vanillic acid (4-hydroxy-3-methoxybenzoic acid)] (Fig. 3.1) all have been identified as potential allelopathic agents.8,32,34 The primary allelopathic effects of these phenolic acids on plant processes are phytotoxic (i.e., inhibitory) they reduce hydraulic conductivity and net nutrient uptake by roots.1 Reduced rates of photosynthesis and carbon allocation to roots, increased abscisic acid levels, and reduced rates of transpiration and leaf expansion appear to be secondary effects. Most of these effects, however, are readily reversible once phenolic acids have been depleted from the rhizosphere and rhizoplane.4,6 Finally, soil solution concentrations of... 

A new model (Fig. 15.4) for hydroxy-cinnamate chain-shortening and vanillin formation in plants was revealed with the isolation of 4-hydroxycinnamoyl-CoA hydratase/lyase (HCHL) and its gene from a soil bacterium, Pseudomonas fluorescens strain AN103, which had been isolated by growth on ferulic acid as a sole carbon source (Gasson et al., 1998 Narbad and Gasson, 1998 Mitra et al., 1999). 

Ferulic acid Ferulic acid CoA 4-Hydroxy-3-methoxyphenyl-(i- Vanillin... 

Suberins. The cork cells in the outer bark contain polyestolides or su-berins. The suberin content in the outer layer of the cork oak bark (cork) is especially high and amounts to 20-40% in the periderm of birch bark. Polyestolides are complicated polymers composed of co-hydroxy monobasic acids which are linked together by ester bonds. In addition, they contain a,/3-dibasic acids esterified with bifunctional alcohols (diols) as well as ferulic and sinapic acid moieties. The chain lengths vary but suberins are enriched with molecules having 16 and 18 carbon atoms. There are also double bonds and hydroxyl groups through which ester and ether cross-links are possible. The outer layer of the epidermis contains so-called cutin, which is heavily branched and has a structure similar to suberin. 

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