Isolation, identification and synthesis of four novel antioxidant peptides from rice residue protein hydrolyzed by multiple proteases.
Multiple proteases were optimized to hydrolyze the rice residue protein (RRP) to produce novel antioxidant peptides. An antioxidant peptide fraction (RRPB3) with IC50 of 0.25 mg/ml was purified from the RRP hydrolysate using membrane ultrafiltration followed by size exclusion chromatography and reversed-phase FPLC. RRPB3 was found to include four peptides (RRPB3 I-IV) and their amino acid sequences were RPNYTDA (835.9 Da), TSQLLSDQ (891.0 Da), TRTGDPFF (940.0 Da) and NFHPQ (641.7 Da), respectively. Furthermore, four peptides were chemically synthesized and their antioxidant activities were assessed by DPPH radical scavenging, ABTS radical scavenging assay and FRAP-Fe(3+) reducing assay, respectively. Both RRPB3 I and III showed synergistic antioxidant activity compared to each of them used alone. All four synthetic peptides showed excellent stability against simulated gastrointestinal proteases. Therefore, the peptides isolated from RRP may be used as potential antioxidants in the food and drug industries.
College of Engineering, China Agricultural University, Beijing 100083, China. Electronic address: yanqj@cau.edu.cn.
Qiao-Juan
QJ
Yan
College of Engineering, China Agricultural University, Beijing 100083, China.
Lin-Hua
LH
Huang
College of Food Science and Nutritional Engineering, Beijing Key Laboratory of Functional Food from Plant Resources, China Agricultural University, Beijing 100083, China.
Qian
Q
Sun
College of Food Science and Nutritional Engineering, Beijing Key Laboratory of Functional Food from Plant Resources, China Agricultural University, Beijing 100083, China. Electronic address: zhqjiang@cau.edu.cn.
Zheng-Qiang
ZQ
Jiang
College of Food Science and Nutritional Engineering, Beijing Key Laboratory of Functional Food from Plant Resources, China Agricultural University, Beijing 100083, China.
Xia
X
Wu
D000975:Antioxidants / Q000737:chemistry*; D006868:Hydrolysis; D012275:Oryza / Q000378:metabolism*; D010084:Oxidation-Reduction; D010447:Peptide Hydrolases / Q000737:chemistry*; D010455:Peptides / Q000737:chemistry*
D000975:Antioxidants; D010455:Peptides; D010447:Peptide Hydrolases
Antioxidant activity; Multiple proteases; Peptides; Rice residue protein; Synthesis