Chlorophyllins

Chlorophyllins are components of green food colorants and coloring foodstuff. However, in spite of its common consumption, the knowledge regarding these compounds is scarce, among other factors due to the complexity of identification. It is frequent to find groups of 2-4 chlorophyll derivatives, potentially present in green natural food colorants, with the same elemental composition, but different functional groups. This significantly increases the difficulty of correct identification, while the unintended misidentification is likely if the occurrence of structural isomers is not noted. We made use of data-dependent MS2 experiments on individual molecular ions to identify new chlorophyll derivatives, which structural arrangement was predictable on the basis of the chemical reactions taking place during the production of food green colorants; to provide qualifier ions by which structural isomers that differ at the sort of branched functional group(s), arising after the hydrolysis of the isocyclic ring, can be distinguished; and to increase our knowledge in chemical behavior of chlorophyll derivatives during MS experiments.
To the best of our knowledge, there is no current existing proposal to discern among structural isomers of chlorophyll derivatives present in marketed green food colorants and coloring foodstuff products. The data we compiled showed the identification of qualifier ions to distinguish among structural isomers of non-coppered chlorophylls. In addition, taking advantage of the capacity of the powerful post-processing software, the fragmentation patterns and structural configuration of each qualifier ions are also ascertained.

叶绿素衍生物是绿色食品着色剂及着色食品的组成部分。尽管其消费广泛，但关于这些化合物的知识却相对匮乏，这其中的原因之一便是其鉴定过程的复杂性。在绿色天然食品着色剂中，常见到由2至4种叶绿素衍生物组成的组合，这些衍生物虽然具有相同的元素组成，但功能团却各不相同。这一现象极大地增加了准确鉴定的难度，若未注意到结构异构体的存在，则可能发生误识别。本研究通过针对单个分子离子进行数据依赖型MS2实验，以识别新的叶绿素衍生物，其结构排列可通过食品绿色着色剂生产过程中发生的化学反应进行预测；通过提供定性离子，以区分在异环结构水解后形成的分支功能团类别的结构异构体；并增强我们对叶绿素衍生物在MS实验过程中化学行为的知识。
据我们所知，目前尚无现有方案能够区分市售绿色食品着色剂及着色食品产品中叶绿素衍生物的结构异构体。我们所收集的数据显示了识别定性离子的结果，这些离子可区分无铜叶绿素的结构异构体。此外，利用强大的后处理软件的能力，还确定了每个定性离子的裂解模式和结构配置。