Glucosinolates and their breakdown products, especially isothiocyanates (ITCs), are hypothesized to exert a broad range of bioactivities. However, physiological mechanisms are not yet completely understood. In this study, formation of protein conjugates after incubation with benzyl isothiocyanate (BITC) was investigated in vitro. A survey of protein conjugates was done by determining BITC cysteine and lysine amino acid conjugates after protein digestion. Therefore, a liquid chromatography-tandem mass spectrometry (LC-ESI-MS/MS) method was developed and validated. Stability studies showed that cysteine conjugates are not stable under alkaline conditions, and lysine conjugates did not show any correlation to pH values, although stability increased at low temperatures. Lysine conjugates were the preferred form of protein conjugates, and longer BITC exposure times led to higher amounts. Knowledge about the reaction sites of ITCs in eukaryotic cells may help to understand the mode of action of ITCs leading to health promoting as well as toxicological effects in humans.

中文翻译：

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异硫氰酸苄酯暴露后通过LC-ESI-MS / MS体外测定人细胞中的蛋白质结合物

推测芥子油苷及其分解产物，特别是异硫氰酸酯（ITC）具有广泛的生物活性。然而，生理机制尚未完全理解。在这项研究中，在体外研究了异硫氰酸苄酯（BITC）孵育后蛋白质结合物的形成。通过测定蛋白质消化后的BITC半胱氨酸和赖氨酸氨基酸结合物，对蛋白质结合物进行了研究。因此，开发并验证了液相色谱-串联质谱法（LC-ESI-MS / MS）。稳定性研究表明，半胱氨酸结合物在碱性条件下不稳定，尽管在低温下稳定性增强，但赖氨酸结合物与pH值没有任何相关性。赖氨酸结合物是蛋白质结合物的优选形式，而较长的BITC暴露时间导致数量增加。有关真核细胞中ITC的反应位点的知识可能有助于了解ITC导致人类健康以及毒理学作用的作用方式。