超高效液相色谱-四极杆-飞行时间质谱定性研究茶叶籽中的酚类化合物

采用超高效液相色谱(UHPLC)-四极杆-飞行时间质谱(Q-TOF/MS)技术定性分析茶叶籽中的酚类化合物。茶叶籽样品经乙醇水溶液提取后经反相色谱分离,通过Q-TOF/MS进行化合物的鉴定。基于山茶属及相关植物化学组成的文献,建立了一个含有106种酚类化合物的数据库。对UHPLC-Q-TOF/MS采集得到的一级质谱数据进行数据库检索,然后对检索到的化合物色谱峰进行二级质谱扫描,根据得到的碎片离子推断化合物的结构。初步推断出茶叶籽提取物中的24种酚类化合物,包括13种酚酸类、4种儿茶素类和7种黄酮类化合物,并通过与标准品比对,进一步确证了这些化合物。结果表明UHPLC-Q-TOF/MS技术可以用于对茶叶籽中酚类化合物进行快速、准确、可靠的定性分析,促进新化合物的发现与鉴别。

Qualitative analysis of phenolic compounds in Camellia Sinensis seeds by ultra-high performance liquid chromatography combined with quadrupole time-of-flight mass spectrometry

Phenol compounds from some plants are considered as the natural anti-oxidants and have been demonstrated with the beneficial biological activities. In this work, the ultra-high performance liquid chromatography (UHPLC) combined with quadrupole time-of-flight mass spectrometry (Q-TOF/MS) was applied to qualitatively determine the phenolic compounds in Camellia Sinensis seeds. The seed sample was extracted using ethanol aqueous solution and further subjected to the UHPLC separation with the reversed phase C18 column as the stationary phase and the acidified acetonitrile/water as the binary mobile phases. The eluent from the column was directed to Q-TOF/MS for compound identification. Based on a number of reports on the chemical components in Camellia Sinensis and the related plants, a customized compound database was initially created including the name and formula of the previously reported 106 phenol compounds. The acquired MS scan data were searched against the customized phenol compound database. The retrieved compounds were then subjected to MS/MS scan, and the obtained fragment ions were applied to further determine the possible structures. A total of 24 phenolic compounds were tentatively identified, including 13 phenolic acids, 4 catechins, and 7 flavonoids, which were characteristic in the ethanol extract according to the available references and the relevant structural information of the molecular and fragment ions. These compounds were further confirmed by matching against the standard compounds in retention times and fragment ions. The results demonstrated that the UHPLC-Q-TOF/MS with the high mass accuracy and the high resolution is a reliable technology for rapid qualitative identification of the phenolic compounds in Camellia Sinensis seeds, promoting the discovery and identification of the new compounds.