Free Ferulic Acid Research Articles

Assay of free ferulic acid and total ferulic acid for quality assessment of Angelica sinensis

Activity of Chinese Danggui (DG), the processed root of Angelica sinensis (Oliv.) Diels, is linked to the ferulic acid content but the stability of ferulic acid during extraction for medicinal use is not known. The stabilities of ferulic acid and coniferyl ferulate were evaluated in the extracts of DG using a variety of extraction solvents. These included various combinations and proportions of methanol, water, formic acid, 1 M aqueous hydrochloric acid and 2% sodium hydrogen carbonate (NaHCO 3) in water. Coniferyl ferulate was found liable to hydrolyze into ferulic acid in neutral, strongly acidic and basic solvents, where heat and water could facilitate this hydrolysis. However, the hydrolysis was relatively resisted in weakly organic acid. Based on the stability evaluation, two new terms, namely: free ferulic acid and total ferulic acid, were suggested and defined. Free ferulic acid refers to the natural content of ferulic acid in herbs. Total ferulic acid means the sum of free ferulic acid plus the amount of related hydrolyzed components. Meanwhile, the high-performance liquid chromatographic (HPLC) method was developed to assay free ferulic acid and total ferulic acid in DG using methanol–formic acid (95:5) and methanol–2% NaHCO 3 in water (95:5) as extraction solvents, respectively. Ten DG samples were investigated on their contents of free and total ferulic acid. The results indicated that the amount variety of free ferulic acid was larger than that of their counterparts, and the ratio of total ferulic acid to free ferulic acid was 4.07 ± 2.73 (mean ± SD, n = 10). The chemical assay of DG using total ferulic acid content would be a better choice to assess the herbal quality and was recommended.

The Release of Ferulic Acid and Feruloylated Oligosaccharides During Wort and Beer Production

Ferulic acid, a very attractive natural antioxidant is present in beer in free form, but the main form is the bound form as feruloylated oligosaccharides. Previous research showed that feruloylated oligosaccharides more effectively inhibited lipid and Low Density Lipoprotein oxidation than free ferulic acid. The aim of the present study was to evaluate free and bound ferulic acid concentrations throughout the brewing process in experimental mashes (worts, beers during fermentation, maturation and storage), and to conduct a comparison in commercial beers. Another aim of the study was to investigate methods to increase levels of bound ferulic acid in beer due to the potential health benefits. Specifically, the influence of commercial enzyme preparations on both forms of ferulic acid contents was studied. Five commercial enzyme preparations during mashing were examined: Celluclast, Shearzyme, Viscozyme, Cereflo and Ultraflo. In all experimental beers, the concentrations of esterified ferulic acid were 4–6 fold higher than the corresponding free ferulic acid contents, depending on the enzyme preparation used. Ferulic acid contents in the ester form in experimental beers were in the range of 748.4 mg/hL to 1244.3 mg/hL, whereas the contents of free ferulic acid were in the range of 134.6 mg/hL to 275.2 mg/hL. Comparison of free and bound ferulic acid contents in experimental beers, produced using enzyme preparations and commercial beers found in a local market, showed that concentrations of bound ferulic acid in experimental beers were significantly higher than in commercial beers, whereas concentrations of free ferulic acid in experimental and commercial beers were comparable.

Release of Ferulic Acid from Wheat Bran by an Inducible Feruloyl Esterase from an Intestinal Bacterium Lactobacillus acidophilus

In the present study, the production of a novel feruloyl esterase (FAE) from a typical human intestinal bacterium Lactobacillus acidophilus using various carbon sources was investigated. The results showed that FAE activity was strongly induced by hemicellulosic substances, with the highest activity detected when de-starched wheat bran (DSWB) was used as a carbon source. Moreover, the production was stimulated by the monosaccharides xylose and arabinose, suggesting its particular secretion mechanism. With increasing levels of free ferulic acid (FA) added, the production of FAE increased, reached a peak and declined. Further, on addition of either xylanase or α-L-arabinofuranosidase, the amount of FA released from DSWB by the purified FAE from L. acidophilus increased from 0 to 12.4nmol and 3.64nmol, respectively. When the three enzymes existed together, 15.7nmol of FA was detected. These results indicated that xylanase is predominant and arabinofuranosidase subordinate in their synergistic effect on FA release by FAE.

4-ビニルグアヤコール含有量を高めた焼酎の製造

The authors attempted the production of shochu fortified with 4-vinylguaiacol (4-VG), which is thought to be the precursor of vanillin. In the small-scale fermentation tests of rice-shochu and awamori, the content of free ferulic acid in mash was increased by the addition of enzyme preparation hemicellulase, and consequently the content of 4-VG in distillate was also increased. The content of 4-VG in distillate increased more with the additional use of wine yeast, which has the ability to generate 4-VG from ferulic acid.

Ferulic Acid Is Quickly Absorbed from Rat Stomach as the Free Form and Then Conjugated Mainly in Liver

Ferulic acid (FA) is one of the most abundant phenolic antioxidants in the human diet. Many studies have documented its beneficial properties. It is therefore essential to understand the absorption and metabolism of FA in detail. The purpose of this study was to confirm the hypothesis that FA is absorbed in rat stomach and metabolized mainly in the liver. We determined the recovery of FA and its metabolites (FA sulfate/glucuronides) in rat gastric contents, gastric mucosa, portal vein plasma, celiac arterial plasma, bile, and urine after 2.25 micromol FA was administered in 0.5 mL physiological saline and incubated for 25 min in situ in the stomach of rats. Within 25 min, 74 +/- 11% of the administered FA disappeared from the stomach; later, FA was recovered in both free and conjugated forms in plasma, bile, and urine. On the other hand, only free FA was detected in the gastric contents and mucosa; it was also detected in the portal vein plasma as 49 +/- 5% of the total FA (all forms of FA). However, the proportion of free FA in the celiac arterial plasma, bile, and urine decreased to 5-8%. These results indicate that FA can be quickly absorbed from the rat stomach, and then is likely metabolized mainly in the liver. Such novel information would be helpful in the use of FA as a nutrient supplement. For example, oral administration of FA in capsule form or in a form bonded with sugar esters may provide a more appropriate concentration of FA in the circulation, which may improve its proposed efficacy in preventing chronic disease.

Ferulate inhibits mixed lymphocyte reaction stimulated cell proliferation and inhibits IL-2 and IL-2 receptor expression

Introduction. We have previously shown that curcumin (di-feruloyl methane) has immunosuppressive properties in addition to its anti-oxidant, anti-inflammation, and anti-mutagenic properties. Ferulic acid is a metabolic product of phenylalanine and tyrosine and also a degradation product of curcumin. In this experiment we investigated whether ferulic acid retained the immunosuppressive properties of curcumin. We used ethyl--ferulic acid (FE, from Sigma) in all our experiments due to its higher water solubility than free ferulic acid and therefore more bioavailable. Methods. Lymphocytes were isolated from human spleen. Mixed lymphocyte reaction (MLR), exogenous IL-2, and PHA-stimulated human lymphocyte proliferation were assayed by 3H-thymidine incorporation. Cell-secreted IL-2 in the culture medium was assayed by ELISA, and IL-2 Receptor (IL-2R) expression was assayed by flow-cytometry. Trypan Blue exclusion was used to rule out direct cytotoxic effects of FE. Microsoft Excel T-test program was used for statistics. P values less than 0.05 were considered statistically significant. Results. MLR stimulated cell proliferation > 8 times over the control response cells. FE at 10, 20, 40 and 80 μM inhibited MLR stimulated 3H-thymidine uptake (CPM/well) from 5349 ± 178 to 4635 ± 119, 4294 ± 125, 3450 ± 79, and 1756 ± 62, respectively ( P < 0.01, n = 6). MLR stimulated IL-2 secretion in the culture medium from control (pg/ml) 24 ± 5.2 to 214.8 ± 5.5. FE at 40 and 80 μM significantly inhibited IL-2 level from 214.8 ± 5.5 to 161.8 ± 6.6 and 138.5 ± 9.6, respectively ( P < 0.04, n = 3). Exogenous IL-2 (0.5 nM) stimulated IL-2 receptor (IL-2R) expression in human lymphocytes from control of 10.52 to 19.95%. FE at 80 μM inhibited exogenous IL-2-stimulated IL-2R expression to 10.95%. Mitogen PHA (5 μg/ml) stimulated IL-2R expression in the lymphocytes from control 10.52 to 58.34%, FE at 80 μM inhibited IL-2R expression to 25.5%. (This experiment has been done once.) Conclusion. FE has immunosuppressive properties like its precursor curcumin but possesses the additional advantage of being bioavailable. These effects warrant further investigation.

Bound ferulic acid from bran is more bioavailable than the free compound in rat.

Ferulic acid (FA) is reported as a good antioxidant absorbed by human or rat but only few data deal with the influence of the food matrix on its bioavailability and with its potential protection against cardiovascular diseases and cancer. Wheat bran is used as a source of ferulic acid, the compound being mainly bound to arabinoxylans of the plant cell walls. Pharmacokinetic profiles of FA and its metabolites are established in rats. Free and conjugated FA quickly appear in plasma, reach a plateau 1 h after intake and remain approximately constant at 1 microM up to 24 h. 2.3% of FA are eliminated in urine. Compared with results obtained after intake of free FA, the presence of FA-arabinoxylans bonds in the food matrix increases the occurrence time of FA in the organism and decreases the level of urinary excretion in 24 h. Nevertheless, sulfated FA is still the main plasmatic form. The antioxidant activity of plasmas of rats fed with a standard diet (containing no FA), pure ferulic acid (5.15 mg FA/kg bw) or bran (4.04 mg FA/kg bw) are measured in an ex vivo test using AAPH as free radical inducer. Plasmas of rats fed with bran show a better antioxidant activity than the control group and the pure FA supplemented group, increasing the resistance of erythrocytes to hemolysis by factors of 2 and 1.5, respectively. These results show the good bioavailability of FA from bran and its potential efficiency to protect organism against pathology involving radical steps of development.

Digestion and absorption of ferulic acid sugar esters in rat gastrointestinal tract.

We estimated the absorption site and absorptivity of ferulic acid (FA) and its sugar esters, namely 5-O-feruloyl-l-arabinofuranose (FAA) and feruloyl-arabinoxylan (FAXn), in rats on the basis of their recovery in intestinal content and feces by comparing the values with those of a nonabsorbable marker, poly R-478. The results indicated that free FA was absorbed almost completely before reaching cecum. About 40% of dietary FAA was absorbed in rat foregut and 57% disappeared in the cecum. In contrast, about 67% of the FA moiety in FAXn was released and then disappeared predominantly in the hindgut. These results suggested that the existing form of FA in diets affects its absorptivity, its absorption site, and its ensuing fate in the gastrointestinal tract. Those ingested FAs esterified with saccharides; especially, polysaccharides have to transit the hindgut where FA might be released and then absorbed and/or degraded by microflora in lumen. Such microbial degradation may be an important factor affecting the bioavailability of dietary FA.

Interaction of water unextractable solids with gluten protein: effect on dough properties and gluten quality

In a previous study, we have shown that water unextractable solids (WUS) interfere with gluten formation and affect the quality of the resulting gluten. In this study we aim to explain how WUS can affect the process of gluten formation. To this end, WUS were modified with NaOH, xylanase, horseradish peroxidase (HRP) and hydrogen peroxide (H2O2). Effects of modified WUS on gluten yield, dough properties, and gluten and glutenin macropolymer (GMP) composition and properties were studied. The results showed that addition of WUS to wheat flour led to a lower gluten yield and gluten starch yield, a higher Rmax and a lower E at Rmax of gluten and a more concentrated and elastic GMP gel. Pretreatment of WUS by NaOH, xylanase, HRP and H2O2 cannot correct its negative effect on gluten yield, but addition of xylanase or free ferulic acid (FA) during gluten separation can remove or prevent the negative effect of WUS on gluten yield. Compared to addition of only WUS, addition of WUS and FA together to wheat flour resulted in a higher gluten yield, a higher E at Rmax of gluten, and a less concentrated and elastic GMP gel. Similar to water extractable pentosans (WEP), FA bound WUS plays a key role in the effect of WUS on gluten yield and properties. It appears that there is a common mechanism regarding the effect of WUS and WEP that the oxidative cross-linking during gluten formation could be prevented by FA addition. The difference between both is that WUS have a higher water binding capacity, which is reflected in a higher Rmax of dough and gluten in the presence of WUS.

Ferulic Acid Sugar Esters Are Recovered in Rat Plasma and Urine Mainly as the Sulfoglucuronide of Ferulic Acid

Ferulic acid sugar esters, the common form of ferulic acid (FA) in cereals, show a stronger antioxidant potential than FA in vitro. However, there is little information on their metabolism and excretion in vivo. In the present study, we investigated the metabolic derivatives of FA in the plasma, urine and feces of rats administered 70 micro mol/kg body of 5-O-feruloyl-L-arabinofuranose (FAA), feruloyl-arabinoxylan (FAXn) or the same molar amount of FA as a comparison. Administered FA and its sugar esters were recovered in rat plasma and urine in the form of free FA, FA-glucuronide, FA-sulfate and FA-sulfoglucuronide (FA-diconjugate with sulfate and glucuronide). The recovery of administered FA in urine was 72%, which was higher than that of administered FAA (54%) or FAXn (20%). Free FA and its derivatives were not recovered in rat feces after FA or FAA administration, but 20% of the administered FA moiety was recovered when FAXn was administered. Moreover, administered FA, in contrast to FA esters, was present in plasma in the free and conjugated forms at a higher concentration but for a shorter time. These results indicated that bioavailability of FA and its sugar esters is dependent on the absence or presence of the saccharide moiety and, in the latter case, its structure. This is the first study to show that FA-sulfoglucuronide is the main metabolite (60-70% of the total) in the plasma of rats administered FA or its sugar esters. Thus, the physiological functions of FA and its sugar esters found in vitro might require reconsideration in vivo.

Production and partial characterisation of feruloyl esterase by Sporotrichum thermophile in solid-state fermentation

A number of factors affecting production of feruloyl esterase an enzyme that hydrolyse ester linkages of ferulic acid (FA) in plant cell walls, by the thermophylic fungus Sporotrichum thermophile under solid state fermentation (SSF) were investigated. Initial moisture content and type of carbon source were consecutively optimised. SSF in a laboratory horizontal bioreactor using the optimised medium allowed the production of 156 mU g −1 of carbon source, which compared favourably with those reported for the other micro-organisms. Optimal esterase activity was observed at pH 8 and 60 °C. The activity of the esterase was measured on an insoluble feruloylated hemicellulose substrate (de-starched wheat bran (DSWB)). De-esterification of wheat straw yielded loss of feruloyl esterase production even though the supplementation of free FA comparable to the alkali-extractable levels of FA found in wheat straw. Chromogenic (fluorogenic) 4-methylumbelliferyl ferulate was used to characterise the multienzyme component, after separation by isoelectric focusing and native PAGE electrophoresis. The zymograms indicated one major esterase activity exhibiting pI and molecular mass values 5 and 27 kDa, respectively.

Differentiation of feruloyl esterases on synthetic substrates in α-arabinofuranosidase-coupled and ultraviolet-spectrophotometric assays

4-Nitrophenyl 5- O- trans-feruloyl-α- l-arabinofuranoside and 4-nitrophenyl 2- O- trans-feruloyl-α- l-arabinofuranoside, synthesized by our group (M. Mastihubová, J. Szemesová, and P. Biely), were found to be suitable substrates for determination of activity of feruloyl esterases (FeEs) exhibiting affinity for 5- O- and 2- O-feruloylated α- l-arabinofuranosyl residues. One assay is based on coupling the FeE-catalyzed formation of 4-nitrophenyl α- l-arabinofuranoside with its efficient hydrolysis by α- l-arabinofuranosidase to release 4-nitrophenol. An alternative assay explores the difference in the molar absorbances at 340 nm of the substrate (ferulic acid esters) and the reaction products, which are (1) free ferulic acid and 4-nitrophenyl α- l-arabinofuranoside in samples free of α- l-arabinofuranosidase and (2) ferulic acid, 4-nitrophenyl α- l-arabinofuranoside, and/or 4-nitrophenol in samples containing α- l-arabinofuranosidase. The new substrates represent convenient tools to differentiate FeEs on the basis of substrate specificity.

Interaction of Water Extractable Pentosans with Gluten Protein: Effect on Dough Properties and Gluten Quality

The effects of modified water extractable pentosans (WEP) on gluten yield, dough properties, gluten quality and composition were studied. The results show that WEP interfere with gluten formation in both a direct and an indirect way. WEP interfere indirectly by competing for water and thus changing conditions for gluten development. This results in a lower gluten yield (GY) and an increased resistance of gluten against extension. The effect on GY can be corrected completely by adding more 0·2% NaCl solution during dough mixing. There is, however, also a direct effect of WEP on gluten formation. This effect is reflected in a lower extensibility of dough and gluten, that cannot be corrected by adding more 0·2% NaCl solution during dough mixing. It is demonstrated that the effect on extensibility of dough and gluten is related to the ferulic acid (FA) content of WEP. Also, addition of free FA leads to a more extensible dough and gluten together with a higher GY. We propose that WEP bound FA plays a key role in determining this effect of WEP. Our results also provide an indication that the effect of WEP on extensibility of dough and gluten may partly be due to cross-linking between protein and WEP.

Dynamic changes in cell wall polysaccharides during wheat seedling development

Changes in arabinoxylan content and composition during development of wheat seedlings were investigated. The cell walls isolated from the seedlings showed an increasing content of arabinoxylan during development, which could be correlated to increased activity of xylan synthase and arabinoxylan arabinosyltransferase. Arabinoxylan changed from initially having a high degree of arabinose substitution to a much lower degree of substitution. β-Glucan was present in the walls at the early stages of development, but was actively degraded after day 4. Increased deposition of arabinoxylan did not take place until β-glucan had been fully degraded. Ferulic and p-coumaric acid esters were present at all points but increased significantly from day 3 to 6, where lignification began. Ferulic acid dimers did not appear in the cell wall until day three and the different ferulic acid dimers varied in the course of accumulation. The ratio of ferulic acid dimers to free ferulic acid was maximal at the time when the wall had been depleted for β-glucan, which had not yet been fully replaced by arabinoxylan. This pattern suggests a role for ferulic acid dimers in stabilizing the wall during the transition from a flexible to a more rigid structure. To investigate if the same changes could be observed within a single seedling, 7 day old seedlings were divided into four sections and the walls were analyzed. Some of the changes observed during the seedling development could also be observed within a single seedling, when analyzing the segments from the elongation zone at the base to the top of the leaf. However, the expanding region of older seedlings was much richer in hydroxycinnamates than the expanding region of younger seedlings. Diferulic acids are stabilizing the wall in the transition phase from an expanding to a mature wall. This transition can take place in different manners depending on the cell and tissue type.

Demethylation of Ferulic Acid and Feruloyl-arabinoxylan by Microbial Cell Extracts

The O -demethylation of ferulic acid and feruloyl-arabinoxylan by the anaerobic bacteria Clostridium methoxybenzovorans (strain SR3) and the facultative aerobic bacteria Enterobacter cloacae (strain DG6) was investigated in order to produce caffeic acid and caffeoyl-arabinoxylan. As both strains produced endocellular enzymes, disrupted cell extracts from these two bacteria were prepared and tested. The SR3-disrupted cell extract was able to produce caffeic acid from free ferulic acid with 84% yield. The use of cysteine as reducing agent in the reaction medium stabilised the highly reactive caffeic acid produced. The DG6-disrupted cell extract used ferulic acid but no caffeic acid was detected, suggesting that it was only an intermediary product of the reaction. None of the two disrupted cell extracts were able to O-demethylate feruloyl-arabinoxylans.

Sulfated Ferulic Acid Is the Main in Vivo Metabolite Found after Short-Term Ingestion of Free Ferulic Acid in Rats

The bioavailability of ferulic acid (FA; 3-methoxy-4-hydroxycinnamic acid) and its metabolites was investigated in rat plasma and urine after an oral short-term ingestion of 5.15 mg/kg of FA. Free FA, glucuronoconjugates, and sulfoconjugates were quickly detected in plasma with a peak of concentration found 30 min after ingestion. Sulfoconjugates were the main derivates ( approximately 50%). In urine, the cumulative excretion of total metabolites reached a plateau 1.5 h after ingestion, and approximately 40% were excreted by this way. Free FA recovered in urine represented only 4.9 +/-1.5% of the native FA consumed by rats. Glucuronoconjugates and sulfoconjugates represented 0.5 +/- 0.3 and 32.7 +/- 7.3%, respectively. These results suggested that a part of FA incorporated in the diet was quickly absorbed and largely metabolized in sulfoconjugates before excretion in urine.

A biotechnological process involving filamentous fungi to produce natural crystalline vanillin from maize bran.

A new process involving the filamentous fungi Aspergillus niger and Pycnoporus cinnabarinus has been designed for the release of ferulic acid by enzymic degradation of a cheap and natural agricultural byproduct (autoclaved maize bran) and its biotransformation into vanillic acid and/or vanillin with a limited number of steps. On the one hand, the potentialities of A. niger I-1472 to produce high levels of polysaccharide-degrading enzymes including feruloyl esterases and to transform ferulic acid into vanillic acid were successfully combined for the release of free ferulic acid from autoclaved maize bran. Then vanillic acid was recovered and efficiently transformed into vanillin by P. cinnabarinus MUCL39533, since 767 mg/L of biotechnologic vanillin could be produced in the presence of cellobiose and XAD-2 resin. On the other hand, 3-d-old high-density cultures of P. cinnabarinus MUCL39533 could be fed with the autoclaved fraction of maize bran as a ferulic acid source and A. niger I-1472 culture filtrate as an extracellular enzyme source. Under these conditions, P. cinnabarinus MUCL39533 was shown to directly biotransform free ferulic acid released from the autoclaved maize bran by A. niger I-1472 enzymes into 584 mg/L of vanillin. These processes, involving physical enzymic, and fungal treatments, permitted us to produce crystallin vanillin from autoclaved maize bran without any purification step.

Thermal and enzymatic treatments for the release of free ferulic acid from maize bran

Different commercial enzyme preparations have been tested to release ferulic acid from maize bran. Best results were obtained with a preparation from Humicola insolens: Novozym 342. However, only 30% of the ferulic acid contained in the bran was released by Novozym 342; moreover, a part (1/3) of the solubilised ferulic acid was still esterified to sugars.Thermal pretreatment (flash-explosion or autoclaving at 160°C) has been tested in order to improve ferulic acid solubilisation. About 80% of ferulic acid contained in the bran was solubilised by a sequential procedure using first a flash-explosion pretreatment of the bran (10% w/v in water) at 180°C (1min) or 190°C (1min) followed after cooling by Novozym 342 treatment (3% w/w protein/bran at 40°C for 24h). Flash-explosion treatment solubilised feruloylated substrates and after Novozym 342 action about 1/3 of solubilised ferulic acid was still esterified to sugars.A similar 80% extent of solubilisation of ferulic acid as feruloylated oligosaccharides was also obtained by autoclaving maize bran (10% w/v in water) at 160°C for 1h. Subsequent treatment with feruloyl esterases was then necessary to get ferulic acid in its free form.

Ferulic Acid Contents in Mugi Miso (Barley-koji Miso) and Antioxidative Activity of Mugi Koji (Barley-koji)

An investigation of the concentration of total ferulic acid (TFA) and free ferulic acid (FFA) in 23 mugi miso (barley-koji miso) and 10 kome miso (rice-koji miso) was performed using high performance liquid chromatograph (HPLC).Mugi miso and kome misocontained 34.8-163.1 (mean 66.2), μg/g and 13.9-33.2 (mean 25.6), μg/g of TFA and 1.4-29.2 (mean 10.7), μg/g and 1.5-12.7 (mean 6.0), μg/g of FFA, respectively. With proliferation ofmugi koji (barley-koji), the amounts of TFA were decreased from 350μg/g to 198ug/g, however, FFA were increased and reached a maximum (80μg/g) after 30 h of culture. The radical scavenging activity of themugi kojiextract (100μM ascorbic acid) was significantly higher than that of non-inoculated barley extract (25μM) and the longer barleymugi kojicultivated, the period cultivatingmugi kojiwas, the higher the scavenging activity became. The radical scavenging efficacy of ethanolic extract ofmugi kojiseemed to be correlated with the amounts of ferulic acid and the other phenolic compounds.

Extraction and Assay of Ferulic Acid Esterase From Malted Barley*

Ferulic acid esterase activity was detected in extracts of barley malt using an assay employing a novel artificial substrate, mono-feruloyl glycerol. Mono-feruloyl glycerol has been synthesized and analysed to determine its degree of substitution and purity. It consists of a mixture of the two isomers 1-feruloyl glycerol and 2-feruloyl glycerol. The extraction of ferulic acid esterase and its assay conditions have been optimised. The presence of both a detergent and reduced glutathione in the extraction medium increased the amount of enzyme extracted. A pH of 7.5 was optimal for enzyme activity. The enzyme in solution was only stable up to 30°C. The crude extract containing the enzyme released free ferulic acid from both soluble and insoluble cell wall materials. After extraction of the soluble enzyme, insoluble enzyme, capable of releasing free ferulic acid from feruloyl glycerol, was detected in the residual grain solids.