Yamamoto R, Suzuki T, Tateda H
J Nutr Sci Vitaminol (Tokyo). 1981;27(5):455-61. doi: 10.3177/jnsv.27.455.
An appropriate procedure for analysis of cystine in the hair has been established, and this procedure was applied to the hair of Japanese women. The recovery of authentic cystine added to a hair sample was 85-90% in 6N HCl hydrolysis, and 96% in acid hydrolysis after performic acid oxidation. The 18-hr acid hydrolysis, but not 4-hr one, was sufficient to digest the hair. In colorimetry by using phosphotungstate, Brown's reagent gave a stable color development. The cystine content by amino acid autoanalysis was significantly correlated with that by the phosphotungstate colorimetry by the modified method of Kassel et al. or of Shinohara. The cystine content in women's hair, which was collected from specimens of different individuals cut during the period from 1910s to 1980, indicated a wide variation ranging from 0.654 to 1.607 mmol half-cystine per g of hair after washing with 0.5% sodium laurylsulfate.
已经建立了一种分析头发中胱氨酸的合适方法，并将该方法应用于日本女性的头发。在6N盐酸水解中，添加到头发样品中的真实胱氨酸回收率为85-90%，在过甲酸氧化后的酸水解中为96%。18小时的酸水解足以消化头发，而4小时的酸水解则不行。在使用磷钨酸盐的比色法中，布朗试剂能产生稳定的显色反应。通过氨基酸自动分析得到的胱氨酸含量与通过卡塞尔等人或筱原的改进方法用磷钨酸盐比色法得到的胱氨酸含量显著相关。从19世纪10年代到1980年期间不同个体剪下的标本中收集的女性头发，在用0.5%十二烷基硫酸钠洗涤后，胱氨酸含量显示出很大差异，范围为每克头发0.654至1.607毫摩尔半胱氨酸。
