Brückner H, Wittner R, Godel H
University of Hohenheim, Stuttgart, F.R.G.
J Chromatogr. 1989 Aug 4;476:73-82. doi: 10.1016/s0021-9673(01)93857-9.
The enantioseparation of standard mixtures composed of protein DL-amino acids was performed by reversed-phase high-performance liquid chromatography of the corresponding diastereomeric isoindolyl derivatives, formed by automated precolumn derivatization with o-phthaldialdehyde (OPA) and a series of N-acyl-L-cysteines(Acyl-Cys). A photodiode-array detector, operating at 338 nm, was used for detection. In order to evaluate systematically the influence of the structures of the acyl group in the chiral thiol reagents, a series of novel N-acyl-L-cysteines was synthesized [acyl = n-butyryl, isobutyryl (i-But), pivaloyl, benzoyl) and the chromatographic behaviour of the diastereomers formed was compared with those of already known reagents, N-acetyl-L-cysteine and N-ter.-butyloxycarbonyl-L-cysteine. All Acyl-Cys derivatives of DL-amino acids were resolved. In particular, i-But-Cys gave the highest resolutions for most of the amino acid enantiomers in comparison with the other Acyl-Cys. Investigation of yoghurt using OPA-acetyl-Cys demonstrated the applicability of the method to a complex food matrix and the occurrence of D-Asp, D-Glu and D-Ala in this dairy product.
通过反相高效液相色谱法，对由蛋白质DL-氨基酸组成的标准混合物进行对映体拆分。该方法是利用邻苯二甲醛（OPA）和一系列N-酰基-L-半胱氨酸（Acyl-Cys）进行自动柱前衍生化，形成相应的非对映异构体异吲哚基衍生物。使用在338 nm波长下运行的光电二极管阵列检测器进行检测。为了系统评估手性硫醇试剂中酰基结构的影响，合成了一系列新型N-酰基-L-半胱氨酸（酰基=n-丁酰基、异丁酰基（i-But）、新戊酰基、苯甲酰基），并将形成的非对映异构体的色谱行为与已知试剂N-乙酰-L-半胱氨酸和N-叔丁氧羰基-L-半胱氨酸的色谱行为进行比较。DL-氨基酸的所有Acyl-Cys衍生物均被拆分。特别是，与其他Acyl-Cys相比，异丁酰基-L-半胱氨酸（i-But-Cys）对大多数氨基酸对映体具有最高的拆分度。使用OPA-乙酰基-L-半胱氨酸对酸奶进行的研究证明了该方法对复杂食品基质的适用性，以及该乳制品中D-天冬氨酸（D-Asp）、D-谷氨酸（D-Glu）和D-丙氨酸（D-Ala）的存在情况。
