Isolation, Characterization and Quantification of Stilbenes from Some Carex Species

Plants of the Carex genus (Family: Cyperaceae) have attracted recent attention as potential food additives due to their high levels of potential bioactive compounds. In this study, the stilbene contents of five unexplored Carex species were investigated: Carex capillacea, Carex hirta, Carex buchananii, Carex cuprina, Carex glauca. High-performance liquid chromatography coupled to mass spectrometry (HPLC–MS) and NMR spectroscopy (NMR) were used to identify the structures. A novel stilbene oligomer, carexinol A, was isolated together with five previously known stilbenes: resveratrol-diglucoside, miyabenol A and C, kobophenol A and α-viniferin. Furthermore, this is the first report of resveratrol diglucoside in Carex genus.