The estimation of arginine.
The estimation of arginine.
复制标题
精氨酸的估计。
作者：
H. Rosenberg;A. Ennor;J. Morrison
精氨酸通过沉淀被估计为苦味酸盐和黄酸盐复合物，酶学上通过精氨酸酶的作用，然后通过微生物学和比色法估计形成的尿素（参见Block & Boiling， 1947）。Sakaguchi （1925a, b）开发的比色法应用最为广泛。这种方法依赖于精氨酸和其他单取代胍类化合物在a-萘酚和碱性次溴酸盐或次氯酸盐存在下生成的红色络合物。尽管这种方法可以定性地检测少量精氨酸，但从数量上来说，它是不可靠的，这一点已被提出的大量修改证明了这一点，G6mez和Marenzi（1953）最近对这些修改进行了审查。Eggleton, Elsden & Gough（1943）介绍了一种用于估计单取代胍和双取代胍的比色法。这些化合物与二乙酰和萘酚在碱性溶液中形成红色的络合物。作者发现，单取代胍如精氨酸和糖胺产生的颜色只有非对称双取代胍如肌酸的九分之一。Ennor & Stocken（1953）和Roche， Thoai & Hatt（1954）证实了这一观察结果。虽然该方法的灵敏度不如Sakaguchi法，但它更简单，更可靠。本文描述了上述反应的一种改性。当在正丙醇和x-萘酚浓度增加的情况下显色时，该方法对单取代胍的灵敏度等于先前用二取代胍获得的灵敏度。因此，可以估计精氨酸的量在10到100微克之间。
Arginine has been estimated by precipitation as the picrate and flavianate complexes, enzymically by the action of arginase followed by the estimation of the urea formed, microbiologically and colorimetrically (cf. Block & Boiling, 1947). The colorimetric method developed by Sakaguchi (1925a, b) has been most widely used. This method relies upon the formation of a red-coloured complex produced by arginine and other monosubstituted guanido compounds in the presence of a-naphthol and alkaline hypobromite or hypochlorite. Although this method will qualitatively detect small quantities of arginine, it is unreliable quantitatively, as evidenced by the large number of modifications that have been suggested, and which have been reviewed recently by G6mez & Marenzi (1953). A colorimetric method for the estimation of both monoand di-substituted guanidines was introduced by Eggleton, Elsden & Gough (1943). These compounds give a red-coloured complex with diacetyl and a-naphthol in alkaline solution. The authors found that monosubstituted guanidines such as arginine and glycocyamine produced only one-ninth of the colour given by asymmetrically disubstituted guanidines such as creatine. This observation has been confirmed by Ennor & Stocken (1953) and by Roche, Thoai & Hatt (1954). Although this method is less sensitive than the Sakaguchi method, it is simpler and more reliable. This paper describes a modification of the above reaction. When the colour is developed in the presence of n-propanol and an increased concentration of x-naphthol, the sensitivity of the method for monosubstituted guanidines is equal to that previously obtained with disubstituted guanidines. Thus it is possible to estimate arginine in amounts ranging from 10 to 100 ,ug.