Simultaneous Determination of Three Coumarins in Angelica dahurica by (1)H-qNMR Method: A Fast and Validated Method for Crude Drug Quality Control

In this study, a quantitative (1)H NMR method ((1)H-qNMR) for determining the contents of imperatorin, byakangelicin, and oxypeucedanin in A. dahurica in traditional Chinese medicine (TCM) has been established. Dried plant material was extracted exhaustively with methanol by an ultrasonication-assisted extraction method. The (1)H-qNMR measurements were performed on a 600 -MHz spectrometer with hydroquinone as the internal standard reference in deuterated dimethyl sulfoxide (DMSO-d(6)) solvent. Quantification was carried out using the (1)H resonance signals at 6.55 ppm for hydroquinone and 7.68, 7.38-7.39, and 6.38-6.39 ppm for imperatorin, byakangelicin, and oxypeucedanin, respectively. The linearity, limit of detection (LOD), limit of quantitation (LOQ), precision, reproducibility, stability, and recovery of the methodology were evaluated, and results were good. The newly developed method has been applied to determine the three coumarins in A. dahurica.