title: Preparation of antioxidative corn protein hydrolysates, purification and evaluation of three novel corn antioxidant peptides.
abstract: Corn gluten meal is a major co-product of corn wet milling. Corn gluten meal was hydrolyzed with Alcalase, Flavourzyme, Alcalase+Flavourzyme and Flavourzyme+Alcalase. At the substrate concentration of 10%, corn protein hydrolysate catalyzed by Alcalase had a degree of hydrolysis of 17.83%, which was higher than that by Flavourzyme (3.65%). The hydrolysate catalyzed by Alcalase+Flavourzyme exhibited better antioxidant activities and was further purified. Three novel antioxidant peptides were purified by a series of chromatographic techniques. Sequences of the three peptides were identified as Cys-Ser-Gln-Ala-Pro-Leu-Ala, Tyr-Pro-Lys-Leu-Ala-Pro-Asn-Glu and Tyr-Pro-Gln-Leu-Leu-Pro-Asn-Glu, respectively. Among the three peptides, Cys-Ser-Gln-Ala-Pro-Leu-Ala exhibited good reducing power and excellent scavenging capacities for DPPH radical and superoxide anion radical, with IC50 values of 0.116 and 0.39mg/ml, respectively. The results from our study indicate antioxidant potency of corn protein hydrolysates and peptides separated from corn gluten meal and can provide basic understanding for the application of corn protein hydrolysates as natural antioxidants.
authors.affiliation: Heilongjiang Provincial Key University Laboratory of Processing Agricultural Products, College of Food and Bioengineering, Qiqihar University, Qiqihar 161006, PR China.
authors.forename: Du-Xin
authors.initials: DX
authors.lastname: Jin
authors.affiliation: Heilongjiang Provincial Key University Laboratory of Processing Agricultural Products, College of Food and Bioengineering, Qiqihar University, Qiqihar 161006, PR China. Electronic address: liuxiaolan001@126.com.
authors.forename: Xiao-Lan
authors.initials: XL
authors.lastname: Liu
authors.affiliation: Heilongjiang Provincial Key University Laboratory of Processing Agricultural Products, College of Food and Bioengineering, Qiqihar University, Qiqihar 161006, PR China. Electronic address: zhengxiqun@126.com.
authors.forename: Xi-Qun
authors.initials: XQ
authors.lastname: Zheng
authors.affiliation: Heilongjiang Provincial Key University Laboratory of Processing Agricultural Products, College of Food and Bioengineering, Qiqihar University, Qiqihar 161006, PR China.
authors.forename: Xiao-Jie
authors.initials: XJ
authors.lastname: Wang
authors.affiliation: Heilongjiang Provincial Key University Laboratory of Processing Agricultural Products, College of Food and Bioengineering, Qiqihar University, Qiqihar 161006, PR China.
authors.forename: Jun-Fang
authors.initials: JF
authors.lastname: He
mesh_terms: D000595:Amino Acid Sequence; D000975:Antioxidants / Q000737:chemistry* / Q000302:isolation & purification; D006868:Hydrolysis; D010084:Oxidation-Reduction; D010449:Peptide Mapping; D010455:Peptides / Q000737:chemistry* / Q000302:isolation & purification; D010940:Plant Proteins / Q000737:chemistry; D011492:Protein Hydrolysates / Q000737:chemistry* / Q000302:isolation & purification; D013381:Subtilisins / Q000737:chemistry; D003313:Zea mays / Q000737:chemistry*
chemical_list: D000975:Antioxidants; D010455:Peptides; D010940:Plant Proteins; D011492:Protein Hydrolysates; D013381:Subtilisins
keywords: Antioxidant property; Corn gluten meal; Hydrolysis; Peptides; Purification