Comprehensive characterization of the in vitro and in vivo metabolites of ziyuglycoside I in rat microsome, intestinal flora, excretion specimen and fresh tissues based on LC-Q-TOF/MS.

Ziyuglycoside I is one of the major active ingredients in Sanguisorba officinalis, a popular medicinal plant in China. In the present study, the metabolites of ziyuglycoside I in rat liver microsome and intestinal flora were identified and structurally characterized, and the metabolic rules were summed based on the LC-Q-TOF/MS system. Then, the metabolites in rat excreta samples were rapidly screened and identified according to the in vitro metabolic rules. Finally, ziyuglycoside I was incubated with fresh liver/lung/kidney/stomach homogenates to further explore the source of the metabolites and reveal the possible metabolic organs involved. Four metabolites in liver microsome were identified as M0-Glu, M0-CH2OH, M0-Glu+CH3, M0-Glu-Ara+CH3. In intestinal flora incubation system, 6 degradation products including M0-Glu-Ara+O, M0-Ara, M0-Glu-COOH, M0-Glu, M0-Glu-Ara+O and M0-Ara+H2O were tentatively identified by interpretation of their accurate MS(1) and MS(2) data. Fifteen metabolites in rat urine and feces were identified, and most of the metabolites were attributed to the transformation in liver microsome and intestinal flora. Specifically, more than a dozen of new metabolites were identified in rat fresh tissues, and ziyuglycoside II was confirmed as the major metabolite in rats.