In vitro antiviral activity of the anthraquinone chrysophanic acid againstpoliovirus

Chrysophanic acid (1,8-dihydroxy-3-methylanthraquinone), isolated from the Australian Aboriginal medicinal plant Dianella longifolia, has been found t o inhibit the replication of poliovirus types 2 and 3 (Picornaviridae) in v itro. The compound inhibited poliovirus-induced cytopathic effects in BGM ( Buffalo green monkey) kidney cells at a 50% effective concentration of 0.21 and 0.02 mug/ml for poliovirus types 2 and 3, respectively. The compound i nhibited an early stage in the viral replication cycle, but did not have an irreversible virucidal effect on poliovirus particles. Chrysophanic acid d id not have significant antiviral activity against five other viruses teste d: Coxsackievirus types A21 and B4, human rhinovirus type 2 (Picornaviridae ), and the enveloped viruses Ross River virus (Togaviridae) and herpes simp lex virus type 1 (Herpesviridae). Four structurally-related anthraquinones - rhein, 1,8-dihydroxyan-thraquinone, emodin and aloe-emodin were also test ed for activity against poliovirus type 3. None of the four compounds was a s active as chrysophanic acid against the virus. The results suggested that two hydrophobic positions on the chrysophanic acid molecule (C-6 and the m ethyl group attached to C-3) were important for the compound's activity aga inst poliovirus. (C) 2001 Elsevier Science B.V. All rights reserved.