title: Emilia sonchifolia extract activity against white spot syndrome virus and yellow head virus in shrimp cell cultures.
abstract: Emilia sonchifolia (L.) DC is a plant used in traditional medicine to treat several viral and bacterial diseases. The antiviral activities of selected Sephadex LH-20 column fractions and HPLC subfractions of an acetone extract of E. sonchifolia leaves were determined in shrimp Penaeus merguiensis primary lymphoid cells infected with either white spot syndrome virus (WSSV) or yellow head virus (YHV). WSSV and YHV replication was quantified using quantitative real-time PCR tests targeted to the VP19 and ORF1b gene transcripts, respectively. In lymphoid organ cells exposed to 100 µg ml⁻¹ of either the Sephadex fraction F14 or the HPLC F14 subfraction SF4, both fractions caused reduced replication, but YHV replication was reduced only by SF4. In the asthiazolyl blue mitochondrial enzyme activity assays to assess extract cytotoxicity, >60% of primary lymphoid organ cells remained viable following exposure to 100 µg ml⁻¹ of either F14 or SF4. GC-MS analysis of the HPLC F14 subfraction SF4 showed that it contained 2,4-di-tert-butylphenol. This study is the first to show that E. sonchifolia leaf extracts might be useful as bioactive agents to protect shrimp against viruses such as WSSV and YHV.
authors.affiliation: Department of Molecular biology and Bioinformatics, Faculty of Science, Prince of Songkla University, Hat Yai, Songkhla 90112, Thailand.
authors.forename: Lamai
authors.initials: L
authors.lastname: Maikaeo
authors.forename: Wilaiwan
authors.initials: W
authors.lastname: Chotigeat
authors.forename: Wilawan
authors.initials: W
authors.lastname: Mahabusarakam
mesh_terms: D000818:Animals; D000998:Antiviral Agents / Q000737:chemistry / Q000494:pharmacology*; D019659:Asteraceae / Q000737:chemistry*; D002478:Cells, Cultured; D033561:Penaeidae / Q000166:cytology; D010936:Plant Extracts / Q000737:chemistry / Q000494:pharmacology*; D046828:Roniviridae / Q000187:drug effects*; D046848:White spot syndrome virus 1 / Q000187:drug effects*
chemical_list: D000998:Antiviral Agents; D010936:Plant Extracts