柱前手性衍生化-高效液相色谱法测定奶山羊瘤胃液中iE-DAP的浓度

Determination of iE-DAP in rumen fluid of lactating goats by Pre-column Chiral Derivatization-HPLC

为了研究高精料日粮模式下丁酸钠对奶山羊瘤胃液中i E-DAP含量的影响,选取10头萨能奶山羊,随机分为高精料组和丁酸钠调控组,建立一种柱前手性衍生化-高效液相色谱（HPLC）法检测γ-D-谷氨酸-内消旋-二氨基庚二酸（iE-DAP）含量,并以邻苯二甲醛（OPA）和N-乙酰基-L半胱氨酸（NAC）为衍生化试剂,以0.05 mol/mL醋酸铵-乙腈（90∶10,V∶V）为流动相,紫外检测器检测波长345 nm。结果显示：在优化的色谱条件下,iE-DAP检测浓度在5-500μg/mL范围内线性关系良好,日内、日间精密度分别为5.35%、6.50%;与高精料组相比,丁酸钠调控组奶山羊瘤胃液中iE-DAP含量极显著降低（P〈0.01）。结果表明：试验建立的方法可行,可用于奶山羊瘤胃液中iE-DAP含量的测定。

To investigate the effect of sodium butyrate supplementation on the concentration of iE-DAP in rumen fluid of lactating goats in high-concentrate diet,10 Saanen dairy goats were chosen and randomly divided into a high-concentrate group and a sodium-butyrate-regulated group. Then,a high performance liquid chromatography（ HPLC） method combined with pre-column chiral derivatization was established to detect the concentration of γ-D-glutamic acid-meso-diaminopi-melic acid（ iE-DAP） in goat rumen fluid. iE-DAP was derivatized with o-phthaldehyde and N-acetyl-cysteine reagent and using a mobile phase consisting of 0. 05 mol/mL ammonium acetate-acetonitrile（ 90： 10）,at the detection wavelength of 345 nm. The results showed that the linear range of iE-DAP was 5-500 μg/mL,the RSDs of intra-day and inter-day were lower than 7%. Compared with the high-concentrate group,the concentration of iE-DAP in the rumen fluid of the sodium-butyrate-regulated group significantly decreased（ P〈0. 01）. The method established here was practical and could be used to effectively detect the concentration of iE-DAP in goat rumen fluid.