柱前衍生化HPLC法测定酱油中(半)胱氨酸的含量

Determination of Cystine (Cysteine) in Soy Sauce with Pre-column Derivation by High Performance Liquid Chromatography

目的探讨建立柱前衍生HPLC法测定胱氨酸和半胱氨酸总含量的方法：方法以二硫代二丙酸（DTDPA）及异硫氰酸苯酯（PITC）为柱前衍生剂，采用反相高效液相色谱法测定酱油中胱氨酸和半胱氨酸总含量。通过对反应温度、反应时间、衍生溶液体积及浓度等影响两步衍生反应效率的因素的研究，获得了优化的实验参数。结果在酱油基质中进行方法认证，线性范围为0．02～1．00mg／ml（R^2=0．9999）。日内和日间精密度RSD〈8％；日内和日间准确度（回收率）分别在100．1％～101．3％和96．4％～103．4％之间，结论本方法适用于酱油中的（半）胱氨酸检测，为鉴别“毛发水酱油”提供了有效的监测手段。

Objective To establish a method of HPLC with pre-column derivation for determination of cystine and cysteine in soy sauce. Method The samples were derived with 3, 3＇-dithiodipropionic acid （DTDPA） and phenylisothiocyanate （PITC）. The cystine and cysteine in soy sauce were determined by reverse-phase high performance liquid chromatography. The experimental parameters that control derivation reaction were studied and optimized, such as reaction temperature, reaction time, concentration and volume of the derivative solution. Results The linear range was 0.02 - 1.00 mg/ml （ R^2 = 0.999 9） . The intra-and interday precisions （described as a percentage of relative standard deviation, RSD） were below 8%. The intra-and inter-day accuracies （described as recovery） were 100.1% - 101.3% and 96.4% - 103.4% , respectively. Conclusion The results showed that this method could be suitable for analysis of cystine and cysteine in soy sauce and could provide effective monitoring mersure for distinguish false soy sauce.