Structural elucidation of eighteen cerebrosides from Holothuria coronopertusa in a complex mixture by high-energy collision-induced dissociation of (M + Li) + ions

Eighteen cerebrosides were detected in admixture from the sea cucumber Holothuria coronopertusa. Their structures have been established on the basis of liquid-secondary ion mass spectrometry (LSIMS)experiments. The collision-induced dissociation (CID)of the lithiated molecules ([M + Li]+)led to diagnostic fragment ions which were further identified by tandem mass spectrometry (MS/MS). In the present study, the combination of LSIMS as ionization mode and high-energy MS/MS analysis appears to be a very powerful method for the rapid analysis of unresolved mixtures of complex molecules.