title: Anticancer and antiviral activities of Youngia japonica (L.) DC (Asteraceae, Compositae).
abstract: Aqueous and ethanol extracts of Youngia japonica (also known as Oriental hawksbeard) were tested in vitro for anti-tumor activity against three cell lines, human promyelocytic leukaemia (HL-60), human myelogenous leukaemia (chronic K-562) and mouse Sarcoma 180 (S-180), and for antiviral activity against respiratory syncytial virus (RSV), influenza A virus (Flu A) and herpes simplex virus type 1 (HSV-1) by cytopathic effect (CPE) reduction assay. Hot water extract of Youngia japonica inhibited cell proliferation and growth of all cancer cell lines to various extent. K-562 cells were the most sensitive to the extract whereas S-180 cells were the least. It did not show any significant cytotoxic effects on normal mammalian Vero cells up to the concentration of 450 microg/mL. The ethanol extract of whole plant of Youngia japonica exhibited antiviral activity against RSV cultured in HEp-2 cells, but did not have any activity against Flu A and HSV-1. Two partially purified fractions (Fr.10 and Fr.11) from the 95% ethanol extract exhibited significant anti-RSV with 50% inhibitory concentration (IC50) in the range of 3.0-6.0 microg/mL. The ratio of the viral titer reduction in the absence (viral control) and presence of the maximal non-cytotoxic concentration (MNCC) of the Fr.10 and Fr.11 was both estimated to be 1 x 10(4) (RF, viral titer reduction factors), indicating that their anti-RSV activity was high enough to justify for further analysis. Our preliminary analysis showed that the antiviral ingredients were likely to contain phenolic compounds including tannins by chemical tests.
authors.affiliation: Department of Biology, The Chinese University of Hong Kong, Shatin, NT.
authors.forename: Linda S M
authors.initials: LS
authors.lastname: Ooi
authors.forename: Hua
authors.initials: H
authors.lastname: Wang
authors.forename: Choi-Wan
authors.initials: CW
authors.lastname: Luk
authors.forename: Vincent E C
authors.initials: VE
authors.lastname: Ooi
mesh_terms: D000818:Animals; D000970:Antineoplastic Agents / Q000494:pharmacology*; D000998:Antiviral Agents / Q000494:pharmacology*; D019659:Asteraceae; D002460:Cell Line; D049109:Cell Proliferation / Q000187:drug effects; D018259:Herpesvirus 1, Human / Q000187:drug effects; D006801:Humans; D009980:Influenza A virus / Q000187:drug effects; D010936:Plant Extracts / Q000494:pharmacology; D012136:Respiratory Syncytial Viruses / Q000187:drug effects; D014407:Tumor Cells, Cultured
chemical_list: D000970:Antineoplastic Agents; D000998:Antiviral Agents; D010936:Plant Extracts