Abstract: The present invention relates to polypeptide-containing compound(s), composition(s) comprising such compound(s) along with divalent metal ions and/or a carbohydrate moiety, their antiviral and anti-hepatoma activities, and the enhancement of activity of antiviral polypeptide-containing agents by their combination with a carbohydrate and at least one divalent metal ion. Preferably, the carbohydrate is a polysaccharide of arabinose and galactose and, independently, the at least one divalent metal ion(s) include magnesium and zinc. The carbohydrate and divalent metal ion can be present in the form of a complex. The composition has been isolated and purified from the root tubers of the Chinese plant, Zei-Bai.