Two New Prenylated Isoflavonoids from Erinacea anthyllis with Antioxidant and Antibacterial Activities

摘要

Two new prenylated isoflavonoids, namely Erinasone A and Erinasone B along with 19 known secondary metabolites, including twelve isoflavonoids, three polyphenols, one flavonol, two flavanones and three steroids, were isolated from the whole plant (roots and aerial parts) of Erinacea anthyllis. Structures of all isolated compounds were elucidated by spectroscopic analysis, including 1D and 2D NMR (H-1, C-13, COSY, HSQC, TOCSY, HMBC and NOESY), mass spectrometry (ESI-MS), UV-Vis, measurement of optical rotation [alpha](D) and by comparison with the literature data. The total phenolic and flavonoid contents were determined in this study. Furthermore, the antioxidant and antibacterial activities of the EtOAc and n-BuOH extracts of E. anthyllis were evaluated. These extracts exhibited moderate antibacterial and antioxidant activities. Their IC50 values were approximately 0.04 mg/mL (n-BuOH) and 0.037 mg/mL (EtOAc). Consequently, Erinacea anthyllis is a rich source of polyphenolic compounds particularly isoflavonoids used as chemotaxonomic markers for the subfamily Papilionoideae of the family Fabaceae.