Abidi S L
U.S. Fish & Wildlife Service, National Fishery Research Center, La Crosse, WI 54602-0818.
J Chromatogr. 1988 Aug 5;447(1):65-79.
Using a reversed-phase high-performance liquid chromatographic (HPLC) technique, a mixture of antimycins A was separated into eight hitherto unreported subcomponents, A1a, A1b, A2a, A2b, A3a, A3b, A4a, and A4b. Although a base-line resolution of the known four major antimycins A1, A2, A3, and A4 was readily achieved with mobile phases containing acetate buffers, the separation of the new antibiotic subcomponents was highly sensitive to variation in mobile phase conditions. The type and composition of organic modifers, the nature of buffer salts, and the concentration of added electrolytes had profound effects on capacity factors, separation factors, and peak resolution values. Of the numerous chromatographic systems examined, a mobile phase consisting of methanol-water (70:30) and 0.005 M tetrabutylammonium phosphate at pH 3.0 yielded the most satisfactory results for the separation of the subcomponents. Reversed-phase gradient HPLC separation of the dansylated or methylated antibiotic compounds produced superior chromatographic characteristics and the presence of added electrolytes was not a critical factor for achieving separation. Differences in the chromatographic outcome between homologous and structural isomers were interpreted based on a differential solvophobic interaction rationale. Preparative reversed-phase HPLC under optimal conditions enabled isolation of pure samples of the methylated antimycin subcomponents for use in structural studies.
采用反相高效液相色谱（HPLC）技术，将抗霉素A混合物分离成八个迄今未报道的亚组分，即A1a、A1b、A2a、A2b、A3a、A3b、A4a和A4b。尽管使用含醋酸盐缓冲液的流动相很容易实现已知的四种主要抗霉素A1、A2、A3和A4的基线分离，但新抗生素亚组分的分离对流动相条件的变化高度敏感。有机改性剂的类型和组成、缓冲盐的性质以及添加电解质的浓度对容量因子、分离因子和峰分辨率值有深远影响。在所研究的众多色谱系统中，由甲醇-水（70:30）和pH值为3.0的0.005 M磷酸四丁铵组成的流动相在分离亚组分方面产生了最令人满意的结果。对丹磺酰化或甲基化的抗生素化合物进行反相梯度HPLC分离，得到了优异的色谱特性，添加电解质并非实现分离的关键因素。基于不同的疏溶剂相互作用原理，解释了同源异构体和结构异构体在色谱结果上的差异。在最佳条件下进行制备型反相HPLC，能够分离出甲基化抗霉素亚组分的纯样品，用于结构研究。
