The anti-DHAV activities of Astragalus polysaccharide and its sulfate compared with those of BSRPS and its sulfate.

This paper studied the anti-duck hepatitis A virus (DHAV) activities of Astragalus polysaccharide (APS) and its sulfate (sAPS) compared with those of Bush Sophora Root polysaccharide (BSRPS) and its sulfate (sBSRPS). The antiviral activities of APS and sAPS were measured by MTT and real-time PCR methods, in vitro. In vivo experiment, the mortality rate and the evaluation indexes of hepatic injury, peroxidative injury and immune level were measured. Just like the condition of BSRPS and sBSRPS, the anti-DHAV activities of sAPS were stronger than those of APS, both in vitro and in vivo. It indicated sulfated modification could enhance the antiviral ability of polysaccharide. But unlike the antiviral effects of BSPRS and sBSRPS in vivo, APS and sAPS did not reduce the mortality rates as their abilities of scavenging free radicals and alleviating the hepatic injuries were weaker than those of BSRPS and sBSRPS. And they even did not enhance the immune levels.