液相色谱-电喷雾质谱联用研究原花青素B3苄硫醇降解产物及反应条件

Study of Components in the Thiolysis Media of Procyanidin B3 with Different Thiolysis Conditions by High Performance Liquid Chromatography/Electrospray Ionization-Mass Spectrometry

采用高效液相色谱-电喷雾串联质谱技术分析了原花青素B3苄硫醇降解过程的目标化合物和副反应产物,比较了不同反应条件对产物生成的影响。延伸单元的杂环裂解产物是反应的主要副产物,占副产物总量的50%以上;表异构化反应主要发生在末端单元。不同硫解条件对末端单元表异构化反应及硫解产率影响显著;在40℃、30 m in条件下,末端单元表异构化率最低(2.2%),硫解产率最高(88.7%),聚合度计算为2.1,适用于原花青素的定性、定量分析。

Depolymerization of procyandin B3 in the presence of benzyl mercaptan nucleophile with different conditions was studied by high performance liquid chromatography/electrospray ionization-mass spectrometry （HPLC/ESI-MASS）. Catechin formed from the terminal unit is more epimerized into epicatechin than benzylthiocatechin formed from the extension unit into benzylthioepicatechin during thiolysis. The heterocyclic ring cleavage product of the extension unit is the main product in the side reaction of thiolysis. It contributes to underestimate the depolymerization yield. The highest deploymerization yield （88.7%） and lowest extent of epimerization （2.2%）obtained with 40℃ 30 min treatment make it suitable for the structural analysis and quantitative determination of proanthocyanidins.