A method was established for simultaneous determination of 21 active constituents including flavanols, isoflavones, flavonols, dihydroflavones, dihydroflavonols, chalcones, pterocarpan, anthocyanidins and phenolic acids in Spatholobi Caulis by ultra fast liquid chromatography with triple quadrupole linear ion trap mass spectrometry(UFLC-QTRAP-MS/MS). Then, it was employed to analyze and evaluate the dynamic accumulation of multiple bioactive constituents in Spatholobi Caulis. The chromatographic separation was performed on a XBridge®C_(18)(4.6 mm×100 mm, 3.5 μm) at 30 ℃ with a gradient elution of 0.3% formic acid aqueous solution-methanol, and the flow rate was 0.8 mL·min~(-1), using multiple-reaction monitoring(MRM) mode. A comprehensive evaluation of the multiple bioactive constituents was carried out by gray correlation analysis(GRA). The 21 target components showed good linearity(r>0.999 0) in the range of the tested concentrations. The average recovery rates of the 21 components were from 97.46% to 103.6% with relative standard deviations less than 5.0%. There were differences in the contents of 21 components in Spatholobi Caulis at diffe-rent harvest periods. Spatholobi Caulis had high quality from early November to early December, which is consistent with the local tradi-tional harvest period. This study reveals the rule of the dynamic accumulation of 21 components in Spatholobi Caulis and provides basic information for the suitable harvest time. At the same time, it provides a new method reference for the comprehensive evaluation of the internal quality of Spatholobi Caulis.
Keywords: Spatholobi Caulis; UFLC-QTRAP-MS/MS; dynamic accumulation; gray relational analysis; multiple bioactive constituents.