Rapid characterization of caged xanthones in the resin of Garcinia hanburyi using multiple mass spectrometric scanning modes: the importance of biosynthetic knowledge based prediction

Abstract

Although the anticancer activities of the resin of Garcinia hanburyi have been well demonstrated, the chemical composition of this medicinal plant is still not fully understood. In this study, a highly effective qualitative method was developed for rapidly profiling the target and non-target caged xanthones in the resin of G. hanburyi. This method mainly involves three steps as follows: (1) prediction of the possible unknown caged xanthones in the resin of G. hanburyi according to the structure characters of the known ones and some well established biosynthetic knowledge; (2) structure classification according to the diagnostic fragment ions (DFIs) of the known caged Garcinia xanthones; (3) detection and characterization of the target and non-target caged xanthones in the resin of G. hanburyi using multiple mass spectrometric (MS) scanning modes. By use of such procedures, mass spectrometric data can be used for confirming the rationally predicted chemical structure rather than sophisticated and time-consumed de novo structure elucidation of a completely unknown component. Finally, a total of 34 caged xanthones including 18 likely new ones from the resin of G. hanburyi were rapidly detected and characterized within one working day.