Method for preparing ACE inhibition peptide originate from fish skin

[0031] Implementation case:

[0032] Weigh 100.0008g of clean tilapia skins, immerse them in 700ml of 0.1mol/L hydrochloric acid solution and 0.1mol/L sodium hydroxide solution for 1hr after degreasing treatment, and wash with distilled water to neutrality, at 45℃. Homogenize with 1000ml of distilled water for 12 hours, extract the supernatant by suction filtration, heat to 50°C-55°C, adjust the pH to 6.0, add 0.04671g papain for constant temperature enzymatic hydrolysis for 2 hours, and then in a water bath at a high temperature of 100°C After heating for 20 minutes, the enzymatic hydrolysis reaction is terminated, and the fish skin proteolysis solution is obtained. The hydrolysis degree of tilapia fish skin protein is 12.3%.

[0033] A compound decolorant (mixed with 3g/L of activated carbon yeast and cyclodextrin) is used to debitter, decolor and deodorize the fish skin proteolysis solution, and collect the supernatant by centrifugal filtration at 4000 r/min. Pass 001*7(732) cation exchange resin at room temperature at a flow rate of 8 times the column volume/h, collect the effluent, and measure its nitrogen recovery rate of 95.40%. Then the decationized hydrolysate is 8 times the column volume/ The flow rate of h passes through 201*7 (717) anion exchange resin, and the effluent is collected. The nitrogen recovery rate is 93.31% and the salt rejection rate is 93.15%. After the effluent is concentrated, it is subjected to ultrafiltration treatment. The working pressure of the ultrafiltration equipment is 28 psi, the temperature of the material liquid is 29°C, the pH of the material liquid is 6.7, and the ultrafiltration treatment is 40 minutes to obtain the fish skin polypeptide liquid.

[0034] The fish skin polypeptide solution was separated by gel chromatography, the separation medium was Sephadex G-15, and the chromatographic column size was 1.6×60cm. Column chromatography conditions: sample amount: 1.5ml; flow rate: 0.8ml/min; eluent: distilled water; detection wavelength: 220nm. Under this separation condition, 8 components are obtained. The high-activity ACE-inhibiting component F is pre-frozen at -80°C for 8 hours and freeze-dried in vacuum for 72 hours to obtain the product. The half inhibitory concentration of each component is shown in Table 2.

[0035] Table 2 The half inhibitory concentration (IC 50 )

[0036] Component