Studies Of Comprehensive Extraction Process Of Antioxidant Peptide And Taurine From Scallop Skirt

Antioxidant peptide has the ability of scavenging free radicals. It can maintain normal metabolism, delay aging, improve the body physiology function, protect the human health. Compared with other antioxidants, it has more antioxidant activity, diversity and security. The natural antioxidant peptide demand is increasingly higher. Therefore, the extraction of antioxidantive peptides from different organisms is the researching hotspots currently. Scallop products have great important economic value in our country. Scallop aquaculture has developed rapidly in recent years, Scallop productions have good taste, is internationally recognized as a high-grade aquatic products. In the scallop production process, it can produce a lot of scallop skirts, which contain rich nutrients and bioactive substances, such as taurine, protein, DHA and so on. People has extracted antioxidant peptide from scallop skirt, but in the preparation process, the taurine was wasted. Taurine has unique physiological functions, is widely used in food and medicine aspects. Studies show that the Scallop skirt can be used as the material to extract taurine, but in the process of production, a large number of proteins are flowed with waste water. If we can extract antioxidant activity peptides and taurine from Scallop skirt by reasonable way, not only can avoid the waste of resources and environmental pollution, but also can maximize the economic benefits.Therefore, we study the comprehensive extraction process of antioxidant peptide and taurine from scallop skirt, getting two extracts at the same time. Mainly through the optimization of scallop skirt protein extraction process; Orthogonal experiment to determine the optimal conditions for alkaline protease, neutral protease, acid protease hydrolyzing scallop skirt proteins; studies antioxidant activity of each peptide fraction and mixed peptide; while extracting scallop skirt proteins, studies the extraction process of taurine from the supernatant after centrifugation of the protein salting. The contents and results show as follows.The optimum extraction of proteins from scallop skirt:scallop skirt pretreatment; solid-liquid ratio 1:5 (m/v), at 4℃ extraction 4h, centrifuged supernatant; 50%-60% saturation ammonium sulfate salting;Four factors and three levels orthogonal experiment to optimize hydrolysis conditions of alkaline protease, neutral protease, acid protease. The result indicated that the optimal technological condition of alkaline protease is:enzyme dosage 6000U/g, pH 11, temperature 45℃, hydrolysis time 4h; the optimal technological condition of neutral protease is:enzyme dosage 8000U/g, pH 7, temperature 45℃, hydrolysis time 3h; the optimal technological condition of neutral protease is:enzyme dosage4000U/g, pH 4, temperature 45℃, hydrolysis time 4h.The antioxidant activity results show that the neutral protease hydrolyzed proteins of scallop skirt have significant hydroxyl radical scavenging activity, the maximum clearance rate is 64.16%, with IC50 of 1.34mg/mL; the acid protease hydrolyzed proteins have general DPPH radical scavenging activity, the maximum clearance rate is 34.76%.Extraction of scallop skirt taurine:the supernatant after protein salting centrifugation is pigment adsorption; distilled water as the eluent, flow rate 1.5mL/ min, sample volume 2mL, making H type strong acidic resin exchange chromatography to obtain pure taurine, measured taurine recovery is 70.26%.