Inhibition of Murine Norovirus and Feline Calicivirus by Edible Herbal Extracts.

Abstract

Human noroviruses (HuNoVs) cause foodborne and waterborne viral gastroenteritis worldwide. Because HuNoV culture systems have not been developed thus far, no available medicines or vaccines preventing infection with HuNoVs exist. Some herbal extracts were considered as phytomedicines because of their bioactive components. In this study, the inhibitory effects of 29 edible herbal extracts against the norovirus surrogates murine norovirus (MNV) and feline calicivirus (FCV) were examined. FCV was significantly inhibited to 86.89±2.01 and 48.71±7.38% by 100μg/mL of Camellia sinensis and Ficus carica, respectively. Similarly, ribavirin at a concentration of 100μM significantly reduced the titer of FCV by 77.69±10.40%. Pleuropterus multiflorus (20μg/mL) showed antiviral activity of 53.33±5.77, and 50.00±16.67% inhibition was observed after treatment with 20μg/mL of Alnus japonica. MNV was inhibited with ribavirin by 59.22±16.28% at a concentration of 100μM. Interestingly, MNV was significantly inhibited with 150µg/mL Inonotus obliquus and 50μg/mL Crataegus pinnatifida by 91.67±5.05 and 57.66±3.36%, respectively. Treatment with 20µg/mL Coriandrum sativum slightly reduced MNV by 45.24±4.12%. The seven herbal extracts of C. sinensis, F. carica, P. multiflorus, A. japonica, I. obliquus, C. pinnatifida, and C. sativum may have the potential to control noroviruses without cytotoxicity.