title: Antiviral effects of persimmon extract on human norovirus and its surrogate, bacteriophage MS2.
abstract: Human noroviruses (NoVs) are the leading cause of gastroenteritis and foodborne illnesses worldwide. In this study, we investigated the effects of persimmon extract (PE) on NoV GII.4 and bacteriophage MS2. We also examined the relationship between the tannin content of PE and its antiviral effects to identify the active ingredient in PE. Different persimmon tannin (PT) solutions were prepared by mixing PE with different concentrations of bovine serum albumin. The antiviral efficacy of these solutions against NoV was evaluated by quantifying the amount of residual noroviral genome using a quantitative reverse transcription PCR (qRT-PCR) assay. The antiviral efficacy of PE against MS2 was examined with an infectivity assay (plaque assay). Solutions containing ≥ 0.11 mg/mL PT reduced the noroviral genome by more than 70.0% and the infectivity of MS2 by more than 2.5 log PFU/mL. However, the effects of PT on both viruses decreased markedly at a concentration of 0.08 mg/mL and solutions containing negligible PT had no antiviral activity. These results suggest that the PT component of PE inactivates NoV and MS2. Our results indicate that PE is a nontoxic antiviral agent effective against enteric viruses.
  
  
  CONCLUSIONS
  Persimmon extract showed antiviral effects against NoV and bacteriophage MS2. Persimmon extract is suitable for use as an antiviral agent.
authors.affiliation: Laboratory of Food Microbiology and Hygiene, Graduate School of Biosphere Science, Hiroshima Univ, 1-4-4, Kagamiyama, Higashi-Hiroshima 739-8528, Japan.
authors.forename: Maki
authors.initials: M
authors.lastname: Kamimoto
authors.forename: Yoshiaki
authors.initials: Y
authors.lastname: Nakai
authors.forename: Toru
authors.initials: T
authors.lastname: Tsuji
authors.forename: Toshi
authors.initials: T
authors.lastname: Shimamoto
authors.forename: Tadashi
authors.initials: T
authors.lastname: Shimamoto
mesh_terms: D000998:Antiviral Agents / Q000494:pharmacology*; D017250:Caliciviridae Infections / Q000821:virology*; D002460:Cell Line; D029788:Diospyros / Q000737:chemistry*; D005517:Foodborne Diseases / Q000821:virology; D005759:Gastroenteritis / Q000821:virology; D006801:Humans; D017909:Levivirus / Q000187:drug effects*; D029322:Norovirus / Q000187:drug effects*; D010936:Plant Extracts / Q000494:pharmacology*; D013634:Tannins / Q000494:pharmacology*; D010948:Viral Plaque Assay
chemical_list: D000998:Antiviral Agents; D010936:Plant Extracts; D013634:Tannins
keywords: antinoroviral agent; bacteriophage; norovirus; persimmon; tannin