Journal of Pharmaceutical Analysis ( IF 8.8 ) Pub Date : 2021-07-21 , DOI: 10.1016/j.jpha.2021.07.007 Xiaodie Li 1, 2 , Changliang Yao 1 , Yun Li 1 , Zhengming Qian 3 , Wenlong Wei 1 , Jianqing Zhang 1 , Jiayuan Li 1 , Qirui Bi 1 , Wenjia Li 3 , Yajun Cui 2 , De-An Guo 1
Cordyceps sinensis (C. sinensis) is a widely used and highly valuable traditional Chinese medicine. Several dipeptides have been detected in C. sinensis, but current scientific knowledge of its chemical makeup remains limited. In this study, an improved approach that integrates offline two-dimensional liquid chromatography (2D LC) separation, precursor ion list, library screening, and diagnostic ion filtering was established to systematically screen and characterize dipeptides in C. sinensis. Offline 2D LC integrating hydrophilic interaction LC and reverse phase separations was established to eliminate interference and identify the target dipeptides. A library containing the potential 400 dipeptides was created, and a precursor ion list with all theoretical precursor ions was adopted to trigger the MS/MS scan with high sensitivity. To identify dipeptides, the type and connection sequence of amino acids were determined according to the product ions. Ile and Leu residues were differentiated for the first time according to the characteristic ion at m/z 69.07. Ultimately, 170 dipeptides were identified or tentatively characterized from C. sinensis, and most are reported for the first time in this species herein. In addition, the identified dipeptides were also applied for discrimination among the three Cordyceps species, and 11 markers were identified. The obtained results provide a deeper understanding of the chemical basis of C. sinensis.
中文翻译:
使用离线 2D LC-LTQ-Orbitrap MS 系统筛选和结构表征二肽:以冬虫夏草为例
冬虫夏草(C. sinensis)是一种用途广泛且价值极高的中药材。在C. sinensis中已检测到几种二肽,但目前对其化学成分的科学知识仍然有限。在本研究中,建立了一种集成离线二维液相色谱 (2D LC) 分离、母离子列表、库筛选和诊断离子过滤的改进方法,以系统地筛选和表征中华白菜中的二肽. 建立了集成亲水相互作用液相色谱和反相分离的离线二维液相色谱,以消除干扰并识别目标二肽。创建了一个包含潜在 400 个二肽的库,并采用包含所有理论母离子的母离子列表来触发高灵敏度的 MS/MS 扫描。为了鉴定二肽,根据产物离子确定氨基酸的类型和连接序列。首次根据m/z 69.07 处的特征离子区分 Ile 和 Leu 残基。最终,从C. sinensis中鉴定或初步鉴定了 170 个二肽,并且大多数是第一次在此物种中报道。此外,鉴定出的二肽也用于3种冬虫夏草的鉴别,鉴定出11个标志物。获得的结果提供了对C. sinensis 化学基础的更深入了解。