Anti-bacterial effects of components from <i>Sanguisorba officinalis</i> L. on <i>Vibrio vulnificus</i> and their soluble epoxide hydrolase inhibitory activity

Sanguisorba officinalis L. is a traditional herbal medicine, which is prevailingly applied to cure hemorrhoids, wounds and ulcers in Eastern Asian countries. The purpose of this study was to investigate the antibacterial and soluble epoxide hydrolase (sEH) inhibitory effects of the extracts and components from S. officinalis. The methanol extract was divided into ethyl acetate (EtOAc), n-butanol (n-BuOH), and water layers. In our screening procedure, the EtOAc and n-BuOH extracts and compounds (1-2) remarkably suppressed the growth of V. vulnificus in a dose-dependent manner. In addition, the EtOAc extract and compound 1 exhibited significant inhibitory effect on the V. vulnificus induced cytotoxicity on HeLa cells. Furthermore, compound 4 displayed an inhibition against sEH with an IC50 value of 7.0 ± 0.5 μM. A kinetic analysis demonstrated that the inhibitory effect of compound 4 was a mixed type, with an inhibitory constant (Ki) 0.22 ± 0.0 μM.