Method for preparing angiotensin I-converting enzyme inhibitory peptide by using squid liver protein

Abstract

The invention relates to a method for preparing angiotensin I-converting enzyme (ACE) inhibitory peptide by using a squid liver protein, which comprises: treating squid liver protein from which fish oil is extracted with acetone to degrease; hydrolyzing the squid liver protein in the presence of pepsase for 18 to 25 hours under conditions that: the hydrolysis temperature is 35 to 38 DEG C, the pH is 1.5 to 2.5, the ratio of the pepsase to a substrate is 2 to 3 percent, and the concentration of the substrate is 1 to 3 percent; and subjecting enzymolysis solution to ultrafiltration treatment, tracking the ACE inhibiting activity of the ACE inhibitory peptide, and separating and purifying the ACE inhibitory peptide by using gel filtration chromatography, diethylaminoethanol (DEAE) anion exchange, reversed-phase-high performance liquid chromatography (RP-HPLC) and other methods. The ACE inhibiting activity of the prepared ACE inhibitory peptide is basically unchanged at a temperature of 2 to 100 DEG C and a pH value of 1 to 12 and is stable; and in a simulation gastrointestinal digestion experiment, the ACE inhibiting activity of the components is not affected, and the peptide still has high ACE inhibiting activity after being digested in gastrointestinal tract. The method is reasonable in process, simple in operation, reduces waste discharge, changes waste materials into valuable materials, and the prepared ACE inhibitory peptide can be used in the field of development of blood pressure reducing foods and medicines.

Description

technical field [0001] The invention relates to a method for deep processing squid liver protein, in particular to a method for preparing angiotensin-converting enzyme (ACE) inhibitory peptide by using squid liver protein. Background technique [0002] During squid processing, wastes such as head, feet, liver and epidermis, which account for 30% of the squid's weight, are generated. For these wastes, the general treatment method is to process fishmeal or bury them, which is not only a huge waste of fishery resources, but also has the problem of environmental pollution. In foreign countries, such as Spain and Japan, the utilization of squid liver adopts its own enzymatic fermentation method to produce squid soluble slurry, squid meal, etc. as fish feed. The utilization and research of squid liver in China still has relatively large development space. At present, there is only the processing of dried squid liver powder, and it is used as feed, and the technical level is not h...

AI Technical Summary

Problems solved by technology

[0006] Since the amino acid composition and structure of ACE inhibitory peptides are quite different, there is no fixed or special amino acid composition, and the composition of proteolysis products is quite complex, which increases the difficulty of its separation and extraction.

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