In depth LC-ESIMSn-guided phytochemical analysis of Ziziphus jujuba Mill. leaves

摘要

Ziziphus jujube Mill. leaves are receiving a great attention for their ability to improve sleep, exerting beneficial effects for both the heart and the central nervous system. With the aim to obtain a comprehensive analysis of the specialised metabolites occurring in the leaves of Z. jujuba, a LC-ESI/(HR)Orbitrap/MS profile in negative ion mode of the methanol extract was carried out. The LC-MS profile guided the isolation of 42 compounds, of which the structures were elucidated by 1D and 2D-NMR experiments. Based on this approach, 2 previously unreported dammarane-type saponins have been characterized along with flavonoid derivatives, dammarane-type saponins and triterpenic acids. Dammarane-type saponins were tested for their cytotoxic activity against A549 and HeLa cancer cell lines. None of the tested compounds, in a range of concentrations between 12.5 and 100 mu M, caused a significant reduction of the cell number.