Identification of the Major Components of Buddleja officinalis Extract and Their Metabolites in Rat Urine by UHPLC-LTQ-Orbitrap.

Buddleja officinalis Maxim, one of the most popular herbal medicines in China, is widely prescribed for curing eye diseases for centuries. In this study, the major components of B. officinalis extract (BOE) and their metabolites in rat urine were detected and identified by ultra-high-pressure liquid chromatography coupled with linear ion trap-orbitrap tandem mass spectrometry (UHPLC-LTQ-Orbitrap). A total of 19 compounds, including 8 flavonoids and 11 phenylethanoid glycosides, were confirmed or tentatively identified from BOE. In vivo, 33 components, including 3 prototypes and 30 metabolies, were confirmed or tentatively identified in rat urine samples. The metabolic pathways of different types of compounds were also proposed. This study would effectively narrow the range of potentially bioactive constituents of BOE and shed light to its action mechanism.