Ferulic acid activities

The antioxidant property of ferulic acid and related compounds from rice bran was reported by Kikuzaki et al, (2002). Their results indicated that these compounds elicit their antioxidant function through radical scavenging activity and their affinity with lipid substrates. Another recent study reported by Butterfield et al, (2002) demonstrated that ferulic acid offers antioxidant protection against hydroxyl and peroxyl radical oxidation in synaptosomal and neuronal cell culture systems in vitro. The effect of ferulic acid on blood pressure (BP) was investigated in spontaneously hypertensive rats (SHR). After oral administration of ferulic acid the systolic blood pressure (SBP) decreased in a dose-dependent manner. There was a significant correlation between plasma ferulic acid and changes in the SBP of the tail artery, suggesting... 

Portions (50 mU MCA-hydrolsing activity) of purified CinnAE were incubated at 37°C with SBP (10 mg), both in the presence and absence of other carbohydrases, in 100 mM MOPS (pH 6.0) in a final volume of 1 mL. Incubations containing boiled enzyme were performed as controls. Reactions were terminated by boiling (3 min) and the amount of free ferulic acid determined using a method described previously for de-starched wheat bran [18]. The total amount of alkali-extractable ferulic acid present in the SBP was 0.87% [5]. 

FAE was identical to these enzymes in requiring an endoxylanase for activity on xylans. Under these circumstances ferulic acid could be released too. It has been observed that for the complete breakdown of different xylans, different enzyme combinations are required, as the substitutions on the xylan chain can vary widely [7]. No activity could be shown on pectins, neither in combination with other AE s and/or pectolytic enzymes. 

Some phenolic acids such as ellagic acid can be used as floral markers of heather honey (Cherchi et al., 1994 Ferreres et al., 1996a,b), and the hydroxyciimamates (caffeic, p-coumaric, and ferulic acids) as floral markers of chestnut honey (Cherchi et al., 1994). Pinocembrin, pinobanksin, and chrysin are the characteristic flavonoids of propolis, and these flavo-noid compounds have been found in most European honey samples (Tomas-Barberan et al., 2001). However, for lavender and acacia honeys, no specific phenolic compoimds could be used as suitable floral markers (Tomas-Barberan et al., 2001). Other potential phytochemical markers like abscisic acid may become floral markers in heather honey (Cherchi et al., 1994). Abscisic acid was also detected in rapeseed, lime, and acacia honey samples (Tomas-Barberan et al., 2001). Snow and Manley-Harris (2004) studied antimicrobial activity of phenolics. 

Effects of Allelochemlcals on ATPases. Several flavonoid compounds inhibit ATPase activity that is associated with mineral absorption. Phloretin and quercetin (100 pM) inhibited the plasma membrane ATPase Isolated from oat roots (33). The naphthoquinone juglone was inhibitory also. However, neither ferulic acid nor salicylic acid inhibited the ATPase. Additional research has shown that even at 10 mM salicylic acid inhibits ATPase activity only 10-15% (49). This lack of activity by salicylic acid was substantiated with the plasma membrane ATPase Isolated from Neurospora crassa (50) however, the flavonols fisetln, morin, myricetin, quercetin, and rutin were inhibitory to the Neurospora ATPase. Flavonoids inhibited the transport ATPases of several animal systems also (51-53). Thus, it appears that flavonoids but not phenolic acids might affect mineral transport by inhibiting ATPase enzymes. 

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. 

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. 

The crystal structures of two ferulic acid complexes of HRP C have been solved, one with resting state enzyme (to 2.0 A resolution) and the other with the cyanide-ligated enzyme (to 1.45 A resolution) 195). These represent a major achievement for the crystallography of peroxidase complexes. The binary complex is heterogenous, according to the 2Fo-Fc omit difference electron density map of the active site. The disordered density observed has been interpreted in terms of three... 

Feruloyl esterase activity was first detected in culture filtrates of Strepto-myces olivochromogenes (49), and has thereafter also been reported for some hemicellulolytic fungi (Table III). A partially purified feruloyl esterase from S. commune liberated hardly any ferulic acid without the presence of xylanase (65). Very recently a feruloyl esterase was purified from Aspergillus oryzae (Tenkanen, M. Schuseil, J. Puls, J. Poutanen, K., /. Biotechnol, in press). The enzyme is an acidic monomeric protein having an isoelectric point of 3.6 and a molecular weight of 30 kDa. It has wide substrate specificity, liberating ferulic, p-coumaric, and acetic acids from steam-extracted wheat straw arabinoxylan. 

To identify ferulic acid, Liebl and Worsham ( ) used weed species in their bioassays that were actually growing in association with wheat (Triticum aestivum L.) in the environment. Thus, there is diversity in terms of which plant species are used in bioassays to indicate biological activity. 

Healy and Young (58) observed that the conversion of vanillic and ferulic acids under anaerobic conditions to methane and CO2 was nearly stoichiometric. More than half of the organic carbon could potentially be converted to methane. This could have great importance in studies where the degradation of phenolic compounds are studied by trapping the evolved CO2. Under anaerobic conditions, part of the normal CO2 evolution may be shifted to methane production with a subsequent low reporting of CO2 evolved, and an underestimation of microbial activity in the soil (51). 

Once the four anionic fractions were isolated (Bi, B2, Xi, X2), their activities were investigated using ferulic or / -fluoroferulic isopropylamine salts as substrates. Rates were plotted as a function of substrate concentration. The Lineweaver-Burk plots obtained (Fig. 4) were not always strictly linear as already reported in the case of ferulic acid and scolopetin oxidation (10,11)- An estimation was made of the apparent Km using the linear part of the plots and results were compared with those obtained for TMB. The values found in this case were in the same order of magnitude, about 0.5 X 10-3 to 1 x 10-3 M. In all extracts, / -fluoroferulic salt inhibited enzyme activity for concentrations higher than 0.25 X 10-2 M. 

The activity of isoperoxidases able to oxidize ferulic acid is not restricted to a few similar substrates such as syringaldazine or TMB. A wider range of substrates are involved (3). Syringaldazine-oxidases from poplar and sycamore are known to react at least with TMB, PPD-PC and guiacol, but their affinity towards the last substrate is 100 to 1000 times lower than for syringaldazine (5,7,9). Similar results were obtained with other materials (12-14). However, other isozymes are not able to react with ferulic acid or syringaldazine (5,7,12,13). 

Antileukemic activity. Aucubin, in combination with caffeic acid, chlorogenic acid, ferulic acid, p-coumaric acid, and vanillic acid, exhibited weak antileukemic activity (inhibitory concentration [ICJjo 26-56 pg/ mL, international system of units 2-11) on human leukemia and lymphoma cell lines. Water-insoluble compounds, such as triterpenoids (oleanolic acid and ursolic acid), monotepene (linalool), and flavonoid (luteolin) produced strong activity " . Anti-nematodal activity. Water extract of the dried seed, at various concentrations, was active on Meloidogyne incognita Anti-yeast activity. Ethanol (80%) extract of the dried entire plant, on agar plate at a concentration of 1 mg/mL, was inactive on Candida albicans K... 

In addition to the presence of natural coumarin derivatives, phytochemical analysis found that dong quai also contains ferulic acid and osthole as ingredients. Ferulic acid was reported to have antithrombotic activity (38). Similarly, study using the closely related Angelica pubescens also found osthole to be antithrombotic (39). These two chemical constituents exert their antithrombotic effects by interfering with different pathways responsible... 

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]. 

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