Determination of bioactive compounds in the nonmedicinal parts of Scrophularia ningpoensis using ultra-high-performance liquid chromatography coupled with tandem mass spectrometry and chemometric analysis.

Although Scrophulariae Radix (root of Scrophularia ningpoensis) has received much attention, little is known about the nonmedicinal parts of S. ningpoensis. A comprehensive evaluation of the multibioactive constituents in the flowers, rhizomes, leaves, and stems of S. ningpoensis during different growth stages would be of value to fully understand the potential medicinal properties of all parts of the plant. Ultra-high-performance liquid chromatography coupled with triple quadrupole mass spectrometry was performed for accurately determining nine compounds in S. ningpoensis. The results indicated the content of total analytes in S. ningpoensis was in the order of flowers (81.82 mg/g) > roots (31.95 mg/g) > rhizomes (26.68 mg/g) > leaves (16.86 mg/g) > stems (14.35 mg/g). The chemometric analysis showed that these plant parts were rich in iridoids and should not be discarded during the processing of medicinal materials. Dynamic accumulation analysis suggested that the early flowering stage was the optimum time for harvesting flowers and appropriate amounts of stems and leaves. Moreover, considering the accumulation of constituents and biomass of medicinal materials, the medicinal parts should be harvested around December with the rhizomes attached. This research provides a theoretical basis and scientific evidence for comprehensive development and utilization of S. ningpoensis resources.