The iridoid glycosides in crude and processed extracts from cornus officinals have been analyzed by high performance liquid chromatography-electrospray ionization mass spectrometry. Samples were analyzed by a reversed-phase C18 column using a binary eluent under gradient conditions. Seven iridoid glycosides could be separated and detected. The [M－H]－ ions of iridoid glycosides in the negative ion mode were observed, which reflect their molecule mass information. An in-source collision induced dissociation (in-source CID) experiment was carried out in order to identify the structures and to measure the contents of iridoid glycosides. The epimers were discovered in the experiment for the first time, namely 7α-O-ethylmorroniside and 7β-O-ethylmorroniside. The chromatographic and mass spectral characterization of iridoid glycosides in cornus officinals was obtained via a high performance liquid chromatography-electrospray ionization mass spectrometry method, which provides an accurate and reliable result to the qualitative and quantitative analysis of cornus officinals.

Key words: cornus officinals, iridoid glycosides, process, HPLC-ESI-MS, CID