Diverse Glycosides from Gardenia latifolia with Antiviral Activity and Chemosystematic Significance

Abstract

AbstractSeveral influenza pandemics have impacted our life, each with variable prevalence and severity. In a search for natural antivirals, further phytochemical investigation of Gardenia latifolia Aiton, Rubiaceae, was conducted. As a result, five structurally diverse glycosides were isolated, offering valuable chemotaxonomic data. Using the crystal violet technique, three isolates, canthoside C, (6R,7S,8S)-7α-[(β-d-glucopyranosyl) oxy] lyoniresinol, and ecdysanrosin A, were evaluated for their anti-influenza A (H1N1) activities. Based on previously reported anti-inflammatory activity of the guaiane class, we investigated the inhibitory effect of (1R,7R,8S,10R)-7,8,11-trihydroxy-guai-4-ene-3-one 8-O-β-d-glucopyranoside, a rare guaiane sesquiterpene glucoside, on inducible nitric oxide (NO) production by Griess assay. Regarding antiviral assay, canthoside C was the most active. It considerably inhibited H1N1 infectivity at an IC50 value of 10.93 µg/ml, showing a selectivity index (SI) of 12.88, compared with acyclovir as a standard. Besides, ecdysanrosin A displayed a moderate selective antiviral activity with an IC50 value of 28.03 µg/ml. Considering their low cytotoxicity on the host cells, canthoside C and ecdysanrosin A have additional merit as potential antiviral agents. Despite the claimed anti-inflammatory activity of guaianes, (1R,7R,8S,10R)-7,8,11-trihydroxy-guai-4-ene-3-one 8-O-β-d-glucopyranoside showed a limited anti-inflammatory activity.