| Ferulic acid is among the most widely distributed phenylpropanoids in plant tissues andesterified to the hemicellulose and etherified to lignin in wheat bran. Physical and chemistrymethods can be used to break up the linking between ferulic acid and hemicellulose, so theesterified ferulic acid exist. Feruloylated oligosaccharides have large development prospectsjust because of their strong physiological functions. Wheat bran is the by-product during wheatprocessing, more than 20 million tons are produced from factory every year. Most of wheatbran are wasted. So preparing feruloylated oligosaccharides from wheat bran is necessary andmeaningful. Extraction, purification and antioxidant function of feruloylated oligosaccharideswere researched in this paper.Wheat bran was hydrolyzed with oxalic acid in order to obtain feruloylatedoligosaccharides in this experiment. Single factor and orthogonal regression design were usedto optimize the extracting conditions in acid experiment. The efficiency of the hydrolysis wasdetermined by the mass of feruloylated oligosaccharides. The optimum conditions were asfollows: concentration of oxalic acid, 0.053mol/L, the ratio of liquid to material, 22.64:1;extracting time, 4.56h. Under these conditions, the mass of feruloylated oligosaccharideswasl.451×10-5mol/g wheat bran; Single factor and central composite design were used in theenzymatic experiment. The efficiency of the hydrolysis was determined by the mass offeruloylated oligosaccharides. The optimum conditions were: the concentration of xylanase30U/g material, the content of material 70g/L, time 6h. Under these conditions, the mass offeruloylated oligosaccharides was 0.811×10-5mol/g wheat bran; Steam boiling treatment wasalso used, the effect of temperature and time on the mass of feruloylated oligosaccharides wereinvestigated. The results were that when boiling temperature was 170℃, boiling time was 10min, the mass of feruloylated oligosaccharides was the highest, it reached 1.153×10-5mol/gwheat bran.Column chromatography was used to purify feruloylated oligosaccharides. AmberliteXAD-2 was selected. The chromatography conditions were: diameter/height, 1/20,concentration of sample, 7.05mmol/L, flow rate, 120mL/h, elution of water, 12 column volume,50％ethanol, 5 column volume, 95％ethanol, 3～5 column volume, under these conditions, theyield of feruloylated oligosaccharides in 50％ethanol part reached 86.87％, the purity was63.48％. Sephadex LH-20 was selected to further separate the sample. Associating withspectrophotometry, paper chromatography, HPLC, IR and MS, the results were that theferuloylated oligosaccharides from acid treatment were FAXX (F-ferulic acid; A-arabinose; X-xylose), FAX, FA; the feruloylated oligosaccharides from enzyme treatment were FAXXX, FAXX, FAX; the feruloylated oligosaccharides from steam boiling treatment were FAXX,FAX,FA.The antioxidation of feruloylated oligosaccharides which purified preliruinarily wasdetermined using hydroxyl free radicals, superoxide anion free radicals, DPPH free radicals,reducing force, lipidosome antioxidation reaction system. The rusults showed that feruloylatedoligosaccharides had strong antioxidation, and some were stronger than ferulic acid. Besides ofthat, feruloylated oligosaccharides prepared by different methods had different extent ofantioxidation. Feruloylated oligosaccharides from acid treatment had stronger antioxidantactivity than others.
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