Deep eutectic solvent on extraction of flavonoid glycosides from Dendrobium officinale and rapid identification with UPLC-triple-TOF/MS

In this study, ultrasonic-assisted deep eutectic solvent (DES) method was used to extract flavonoids from Dendrobium officinale. The mechanism of DESs extraction differences was investigated by physicochemical characterization and molecular dynamics simulation experiments. Moreover, flavonoids from Dendrobium officinale were rapidly identified and quantitatively analyzed by UPLC-Triple-TOF/MS without removing DES. The results showed choline chloride-lactic acid (Chol-Lac) had the best extraction effect among forty groups of DESs, the extraction yield was up to 35.23 ± 2.12 mg/g. It was speculated that the tight hydrogen bond structure was the key to the better extraction ability of Chol-Lac. Meanwhile, the viscosity was the main physical parameter reflecting the hydrogen bond structure of DES. Fourteen flavonoid glycosides were identified, among which the content of rutin (1.94 ± 0.24 mg/g) was the highest. And the results of cluster analysis showed that different DESs had great differences in the extraction of flavonoid glycosides.