Gehrke C W, Rexroad P R, Schisla R M, Absheer J S, Zumwalt R W
J Assoc Off Anal Chem. 1987 Jan-Feb;70(1):171-4.
The sulfur-containing amino acids cystine and methionine play important roles in animal, especially avian, nutrition. Because these sulfur-containing amino acids are destroyed to varying extents by 6N HCl hydrolysis, oxidation and hydrolysis of cystine to cysteic acid and methionine to methionine sulfone have been widely used for determination of cystine and methionine. Lysine is considered the next limiting amino acid after the sulfur amino acids in poultry nutrition; therefore, determination of the amino acid content of rations focuses first on these 3 amino acids. The objective of this investigation was to establish whether lysine and other amino acids could be accurately determined in proteinaceous materials which had undergone performic acid oxidation. To perform this evaluation, lysine was determined in a variety of protein-containing materials both with and without performic acid oxidation. Performic acid oxidation followed by 6N HCl hydrolysis at 145 degrees C for 4 h allows accurate measurement of 3 amino acids especially important to poultry nutrition, cystine, methionine, and lysine, in a single preoxidized hydrolysate; this method can be extended to another 9 protein amino acids.
含硫氨基酸胱氨酸和蛋氨酸在动物尤其是禽类营养中发挥着重要作用。由于这些含硫氨基酸在6N盐酸水解过程中会受到不同程度的破坏，因此胱氨酸氧化水解为半胱氨酸、蛋氨酸氧化为甲砜基蛋氨酸已被广泛用于胱氨酸和蛋氨酸的测定。在禽类营养中，赖氨酸被认为是仅次于含硫氨基酸的第二限制性氨基酸；因此，日粮氨基酸含量的测定首先关注这三种氨基酸。本研究的目的是确定在经过过甲酸氧化的蛋白质材料中是否能够准确测定赖氨酸和其他氨基酸。为了进行该评估，对多种含蛋白质材料在进行过甲酸氧化和未进行过甲酸氧化的情况下测定赖氨酸。过甲酸氧化后，在145℃下用6N盐酸水解4小时，可以在单一的预氧化水解产物中准确测量对禽类营养特别重要的三种氨基酸，即胱氨酸、蛋氨酸和赖氨酸；该方法可以扩展到另外9种蛋白质氨基酸。
