The antiviral activity of leaves of Eucalyptus camaldulensis (Dehn) and Eucalyptus torelliana (R. Muell).

Human enteroviruses are the major cause of aseptic meningitis and are resistant to all known antibiotics and chemotherapeutic agents. Methanolic extracts of Eucalyptus camaldulensis and Eucalyptus torelliana were tested on human enteroviruses: Poliovirus type I, Coxsackievirus B and Echovirus 6. The virucidal tests showed that the crude extracts were active on the test viruses: poliovirus type 1, coxsackievirus B and echovirus 6 giving a neutralization index of one log and above. The cytotoxicity assay of the crude extracts to L20B (a genetically engineered mouse cell line) and human rhabdomyo sarcoma (RD) cells showed that the extract of E. torelliana was more toxic than the extract of E. camaldulensis. The antiviral study showed that the extract of E. torelliana was more active than that of E. camaldulensis.