title: Production of hydrolysate with antioxidative activity by enzymatic hydrolysis of extruded corn gluten.
abstract: Hydrolysate of extruded corn gluten with higher solubility and antioxidative property was prepared. Extrusion and starch removal of corn gluten were applied as pretreatment before enzymatic hydrolysis by Alcalase. The amylase hydrolysis of starch at 70 degrees C for 3 h resulted in the removal of the starch from the extruded corn gluten. The best hydrolysis results can be obtained by conducting the hydrolysis at 60 degrees C with water addition 20 g/g protein, enzyme addition 0.048 Ansen units/g protein, pH 8.5, and 120 min. Degree of hydrolysis of extruded and nonextruded corn gluten reached 39.54 and 31.16%, respectively, under the optimal condition. Sodium dodecyl sulfate polyacrylamide gel electrophoresis of the optimal hydrolysate revealed that proteolysis of extruded corn gluten was more extensive than proteolysis of its counterpart which was not subjected to extrusion. The molecular weight of the peptides in the optimal hydrolysate was mainly over 3,710-660 Da as determined by gel filtration chromatography. The hydrolysates displayed good solubility and antioxidative activity. The separation profile of the hydrolysate on an ion exchange chromatography of Q-Sepharose Fast Flow showed that many kinds of peptides had antioxidative effect. A new peptide with antioxidative activity was purified, and its amino acid sequence was Phe-Pro-Leu-Glu-Met-Met-Pro-Phe, which was identified by Q-TOF2 mass spectrometry.
authors.affiliation: College of Food Science and Nutritional Engineering, China Agricultural University, Beijing 100083, People's Republic of China. zxq001@126.com
authors.forename: Xi-qun
authors.initials: XQ
authors.lastname: Zheng
authors.forename: Li-te
authors.initials: LT
authors.lastname: Li
authors.forename: Xiao-lan
authors.initials: XL
authors.lastname: Liu
authors.forename: Xiao-jie
authors.initials: XJ
authors.lastname: Wang
authors.forename: Jie
authors.initials: J
authors.lastname: Lin
authors.forename: Di
authors.initials: D
authors.lastname: Li
mesh_terms: D000595:Amino Acid Sequence; D000975:Antioxidants / Q000378:metabolism* / Q000494:pharmacology*; D001709:Biotechnology / Q000379:methods; D002850:Chromatography, Gel; D002852:Chromatography, Ion Exchange; D004591:Electrophoresis, Polyacrylamide Gel; D005983:Glutens / Q000302:isolation & purification / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D006868:Hydrolysis; D013058:Mass Spectrometry; D008970:Molecular Weight; D010455:Peptides / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology; D011492:Protein Hydrolysates / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism* / Q000494:pharmacology*; D012995:Solubility; D013213:Starch / Q000302:isolation & purification; D013381:Subtilisins / Q000378:metabolism*; D013696:Temperature; D013997:Time Factors; D003313:Zea mays
chemical_list: D000975:Antioxidants; D010455:Peptides; D011492:Protein Hydrolysates; D005983:Glutens; D013213:Starch; D013381:Subtilisins