基于HPLC-Q-TOF MS的网络化技术对宁夏枸杞根皮的化学成分研究

Analysis of Chemical Constituents in the Root Bark of Lycium barbarum L.by HPLC-Q-TOF MS Combined with Networking

建立了高效液相色谱-四极杆-飞行时间质谱(HPLC-Q-TOF MS)法分析宁夏枸杞根皮的主要化学成分。采用Agilent ZORBAX Extend C18柱(250 mm×4.6 mm×5μm),以水(含10 mmol/L醋酸铵)-乙腈为流动相进行等度洗脱,流速1.0 mL/min,柱温30℃,进样量5μL;电喷雾离子源正、负离子模式检测,质量扫描范围m/z 100~300和300~2000。利用数据转换软件将原始数据转换成mzXML格式,在GNPS上建立分子网络,并运用Cytoscape软件对结果进行可视化解读,结合文献数据推测化合物结构。通过手动检索发现了宁夏枸杞根皮中的21个化合物,与已报道的枸杞根皮中化合物一致。通过分子网络化聚类分析发现11个化合物,为地骨皮中首次报道,其中化合物24和25为新发现的环九肽类化合物。该方法可快速分析宁夏枸杞根皮的化学成分,为其质量控制奠定基础。

In the past decades,systematic isolation and structural identification of chemical components from plant material,especially traditional Chinese medicine,have provided a large number of chemical drugs and lead structures for clinic.However,there are still a large number of trace components in traditional Chinese medicine with novel chemical structures and specific pharmacological activities,which need to be further analyzed.With the development of modern analytical technology,the network technology based on tandem mass spectrometry and cluster analysis shows many advantages in trace analysis of complex components.In this paper,a method of high-performance liquid chromatography quadrupole time-of-flight mass spectrometry(HPLC-Q-TOF MS)was developed for the analysis of the main chemical constituents in the root bark of Lycium barbarum L.The aqueous extract sample was separated by methanol aqueous through C18-solid phase extraction,and then the 50%methanol aqueous elution was analyzed using HPLC-Q-TOF MS with C18 column.The ions were monitored in both positive mode and negative mode of ESI with the scanning ranges of m/z 100-300 and 300-2000.The trace chemical components were analyzed by molecular network technology.The MS data files were converted to the mzXML format and the molecular network was generated on GNPS,then visualized with Cytoscape,and the structures of compounds were predicted based on literature data.Twenty one known compounds in Cortex Lycii were verified by manual analysis technique and eleven new components were firstly identified by molecular networking.It is worth reporting that compound 24 and 25 are different from cyclooctapeptides previously found in the root bark of Lycium chinense(another source of Cortex Lycii),indicating that they can be used as markers for the identification of two species of Cortex Lycii.This work lays a research foundation for promoting the effective application of Lycium barbarum L.root bark.