PROTEIN ASSAY METHOD

Protein is a high molecular compound formed by the combination of amino acids by peptide bonds. Traditional methods of protein detection, such as Kjeldahl method, ultraviolet method and biuret method, are all based on the properties of proteins, which are not very accurate and cannot reflect the differences of proteins from different sources. If the true type and content of amino acids that make up proteins can be obtained, it is crucial in biological research and food quality evaluation. By accurately determining the types and contents of protein amino acids in the constituent samples, it can be helpful for the exploration of biological pathology and other aspects. Because the nutritional value of protein in food is determined by the type and content of essential amino acids, it is also helpful to determine the nutritional value of protein in food, so as to avoid the occurrence of "melamine milk safety incident" and "leather protein milk powder incident". However, in the literature, the methods of protein hydrolysis, such as acid method, alkali method and enzymatic method, are insufficient, which cannot make the amino acids in the hydrolyzed products consistent with the amino acids that actually constitute proteins. Therefore, it is impossible to detect proteins actually by the method of detecting amino acids. The proteolytic agent used in the present invention is p-phenolic sulfonic acid, and the solution is prepared with a certain proportion of ethanol, methanol or acetonitrile and other aqueous solutions. Compared with the traditional proteolytic method, this hydrolytic agent is mild and has no destructive effect on tryptophan and other unstable amino acids. The amino acids obtained by hydrolysis can be analyzed by amino acid analyzer, liquid chromatography or gas chromatography, and the types and contents of amino acids that constitute proteins can be accurately obtained, and the contents of proteins can be calculated by adding amino acids together. By using amino acid analysis to detect proteins, the types.

Protein is a high molecular compound formed by the combination of amino acids by peptide bonds. Traditional methods of protein detection, such as Kjeldahl method, ultraviolet method and biuret method, are all based on the properties of proteins, which are not very accurate and cannot reflect the differences of proteins from different sources. If the true type and content of amino acids that make up proteins can be obtained, it is crucial in biological research and food quality evaluation. By accurately determining the types and contents of protein amino acids in the constituent samples, it can be helpful for the exploration of biological pathology and other aspects. Because the nutritional value of protein in food is determined by the type and content of essential amino acids, it is also helpful to determine the nutritional value of protein in food, so as to avoid the occurrence of "melamine milk safety incident" and "leather protein milk powder incident". However, in the literature, the methods of protein hydrolysis, such as acid method, alkali method and enzymatic method, are insufficient, which cannot make the amino acids in the hydrolyzed products consistent with the amino acids that actually constitute proteins. Therefore, it is impossible to detect proteins actually by the method of detecting amino acids. The proteolytic agent used in the present invention is p-phenolic sulfonic acid, and the solution is prepared with a certain proportion of ethanol, methanol or acetonitrile and other aqueous solutions. Compared with the traditional proteolytic method, this hydrolytic agent is mild and has no destructive effect on tryptophan and other unstable amino acids. The amino acids obtained by hydrolysis can be analyzed by amino acid analyzer, liquid chromatography or gas chromatography, and the types and contents of amino acids that constitute proteins can be accurately obtained, and the contents of proteins can be calculated by adding amino acids together. By using amino acid analysis to detect proteins, the types.