title: Antiviral activity of aqueous and ethanol extracts and of an isolated polysaccharide from Agaricus brasiliensis against poliovirus type 1.
abstract: OBJECTIVE
  Agaricus brasiliensis (previously named Agaricus blazei ss. Heinem), also known as the sun mushroom is native of Southeast Brazil, and is widely consumed, mainly in the form of tea, due to its nutritional and pharmacological properties. In this study, we tested aqueous (AqE) and ethanol (EtOHE) extracts and an isolated polysaccharide (PLS) from the fruiting body of A. brasiliensis, for antiviral activity against poliovirus type 1 in HEp-2 cells.
  
  
  RESULTS
  The evaluation of the time of addition by plaque assay showed that when AqE, PLS and EtOHE were added, just after the virus inoculation (time 0 h), there was a concentration-dependent reduction in the number of plaques up to 50%, 67% and 88%, respectively, with a selectivity index (SI) of 5.4, 9.9 and 12.3, respectively.
  
  
  CONCLUSIONS
  The test substances showed antiviral activity and were more effective when added during the poliovirus infection. As they had little effect on reducing viral adsorption and did not show any virucidal effect, we suggest that they act at the initial stage of the replication of poliovirus.
  
  
  CONCLUSIONS
  These results corroborate that basidiomycetes can be a rich source of potential antiviral compounds.
authors.affiliation: Departamento de Microbiologia, Universidade Estadual de Londrina, Londrina, Paraná, Brazil.
authors.forename: L C
authors.initials: LC
authors.lastname: Faccin
authors.forename: F
authors.initials: F
authors.lastname: Benati
authors.forename: V P
authors.initials: VP
authors.lastname: Rincão
authors.forename: M S
authors.initials: MS
authors.lastname: Mantovani
authors.forename: S A
authors.initials: SA
authors.lastname: Soares
authors.forename: M L
authors.initials: ML
authors.lastname: Gonzaga
authors.forename: C
authors.initials: C
authors.lastname: Nozawa
authors.forename: R E
authors.initials: RE
authors.lastname: Carvalho Linhares
mesh_terms: D000364:Agaricus / Q000737:chemistry* / Q000254:growth & development; D000998:Antiviral Agents / Q000302:isolation & purification / Q000494:pharmacology / Q000633:toxicity; D045744:Cell Line, Tumor; D000431:Ethanol / Q000737:chemistry; D006801:Humans; D008826:Microbial Sensitivity Tests; D017955:Poliovirus / Q000187:drug effects* / Q000502:physiology; D011134:Polysaccharides / Q000302:isolation & purification / Q000494:pharmacology / Q000633:toxicity; D014779:Virus Replication / Q000187:drug effects*; D014867:Water / Q000737:chemistry
chemical_list: D000998:Antiviral Agents; D011134:Polysaccharides; D014867:Water; D000431:Ethanol