Research Of Preparing Cherry Seeds Antioxidant Peptides By Enzymatic Method

With the rapid development of cherry processing industry, the environment pollution and resources wasting are daily highlighted brought by the large amounts of byproduct – cherry seeds, its the deep processing and comprehensive utilization are brought to the forefront. The cherry seed contains various nutritions, especially the protein occupies 30-40% of its dry weight, which is consider to be the proper raw material producing antioxidant peptide. This research took the cherry seed protein isolate as the raw material and biotechnology, applying the food high-technology, isolation and purification technology and modern instrumental analysis to obtain two kinds of peptides with higher antioxidant ability, and the main result was as followed:1. The compounding procedure was determined as synergistical hydrolysis with Alcalase and Neutrase, taking the Degree of Hydrolysis and Yield of Peptide as indicators. The optimum enzymatic hydrolysis parameters was obtained by single factor experiment, Plackett-Burman experiment, Box-Behnken design and response surface analysis as follow: ratio of material to solvent 3.82%, enzyme adding dosage 4823 U/g, enzyme proportion 1:1, pH 7.5, temperature 48.77 ℃, time 128 min. The Yield of Peptide was 41.90% under the optimum condition.2. In order to isolate and purify cherry seed antioxidant peptide, ultrafiltration, gel filtration, semi-preparative RP-HPLC were applied and the scavenging abilities of hydroxyl radical, superoxide anion radical, DPPH radical, ABTS radical were used for evaluating the antioxidant properties. Two potent peptides F-IV-E(a)-4 and F-IV-E(a)-5 were obtained, which the E(a)-4 had higher DPPH radical scavenging ability while the E(a)-5 had higher superoxide anion radical scavenging ability, at the concentration of 5 mg/m L.3. To identify the amino sequences and molecular weights of the two peptides F-IV-E(a)-4 and F-IV-E(a)-5, Q-TOF-MS and 494 protein sequencer were applied, and they are Phe-Pro-Glu-Leu-Leu-Ile(731.92 Da [M+H]+) and Val-Phe-Ala-Ala-Leu(520.61 Da [M+H]+).