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Wheat gluten is a byproduct of wheat starch production process, due to the poor solubility in water, limited food, improve its solubility and enhance its added value, and to broaden the scope of its application, the enzymatic hydrolysis of wheat protein, Wheat active polypeptide having the biological activity was obtained. On the basis of the preliminary studies, mainly double enzyme co-hydrolyzed wheat gluten to get the most antioxidant activity, relative to a single component antioxidant peptide obtained through a variety of means of separation and purification, and its in vitro antioxidant activity system analysis, the final identification of its structural features, as well as the amino acid sequence. The main conclusions are as follows: 1) First of all, on the basis of the preliminary study, the degree of hydrolysis and antioxidant activity indicators, the investigated alkaline protease, acid protease, papain, bromelain, trypsin, and wheat hydrolysis special enzyme and neutral The effect of the protease combination hydrolyzed wheat gluten protein. The results showed that the strongest antioxidant activity of the the neutral protease trypsin combination. Through the addition ratio of the two kinds of enzymes, temperature, pH, substrate concentration, plus the impact of factors such as the amount of enzyme and reaction time on the hydrolysis product of DPPH radical scavenging, to obtain the best enzymatic process conditions: neutral protease / trypsin = 2/1, 9% of the wheat gluten protein concentration, enzyme dosage of 0.07 at pH 9, the temperature of 50 ° C, hydrolysis time of 1.5h, DPPH clearance rate up to 92.87%. 2) Second, in optimum conditions, wheat protein hydrolyzate, a preliminary separation of the ultrafiltration membranes of different MWCO (10000,5000,3000 Da) on wheat gluten Hydrolysates, to obtain D-WG (enzymatic dope) , D-WG-10 (GT; 10000Da), D-WG-5 (5000 to 10000Da), D-WG-(3000 ~~ 5000 Da), and the D-the WG-0 (lt; 3000 Da), etc., 5 kinds of different molecular weights group minutes. Compare the above peptides of the antioxidant activity (DPPH radical scavenging O2-inhibitory activity, the inhibitory activity of hydroxyl radicals, and reducing power) to obtain a peptide fragment of the D-WG-0 has the strongest antioxidant activity. Further further purified using Sephadex G-25 and DEAE-Sepharose FF, to obtain the component relative to a single polypeptide of the D-WG-0-Ⅰ. RP-HPLC purity of the component is identified found that the purity was 84%. 3) Finally, inspect D-WG-0-I mouse liver tissue MDA formation, swelling of mouse liver mitochondria and red blood cell hemolysis effect of further study D-WG-0-1 antioxidant activity, the results show D-WG-0-1 has the potential to act as antioxidants. And means of ultraviolet spectroscopy, infrared spectroscopy and MALDI-TOF/TOF-MS carried out a systematic analysis of the structure of the D-WG-0-Ⅰ determined its amino acid sequence Ser-Gly-Ala-Asp-Lys-Lys-Pro -Ile-Lys-Ala-Asn-His.
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