Abstract: Nerium indicum Mill.was used in traditional medicines around the world,particularly in Asia.To identify the bioactive substances and evaluate the safety of N.indicum for clinical purpose,we characterised the root of N.indicum using ultra performance liquid chromatography separation coupled with quadrupole time-of-flight mass spectrometry (UPLC-QTOF-MS),and 22 cardiac glycosides were found as the main components.Their possible structures were given.Among the 22 compounds,13 compounds were reported for the first time in Nerium genus.In conclusion,the UHPLC-QTOF/MS method is useful and efficient technique to separate and identify possible chemical compounds in complex matrices of herbal medicines such as N.indicum.

Key words: Nerium indicum Mill., bioactive compound, ultra-performance liquid chromatography, quadrupole time-of-flight mass spectrometry