title: Photoprotective and toxicological activities of extracts from the Antarctic moss Sanionia uncinata.
abstract: BACKGROUND
  The Antarctic moss Sanionia uncinata (Hedw.) Loeske has shown high ultraviolet (UV)-absorbers content after exposition to high levels of UV-B radiation and can be an important source of antioxidants.
  
  
  OBJECTIVE
  The aim was to investigate photoprotection and mutagenicity by the aqueous extract (AE) and hydroethanolic extract (HE) from the Antarctic moss S. uncinata.
  
  
  METHODS
  Photoprotective activities were determined through survival curves of Escherichia coli strains, after UV irradiation in an aqueous solution of thymine and in vitro sun protection factor (SPF). The Salmonella/microsome assays were applied to assess the mutagenicity.
  
  
  RESULTS
  Both extracts induced photoprotection against UV-C radiation. The AE showed a higher protection than the hydroethanolic one against UV-induced thymine dimerization. The SPFs were low in both extracts. In association to benzophenone-3 a significant increase in the SPF was detected for the AE, and a significant decrease was induced by the HE. No mutagenicity was found in the both extracts. Furthermore, it was observed absence of cytotoxicity.
  
  
  CONCLUSIONS
  Water-extractable compounds seem to contribute on photoprotection of this Antarctic moss.
authors.affiliation: Department of Biophysics and Biometry, Institute of Biology Roberto Alcantara Gomes, Rio de Janeiro State University, Rio de Janeiro, Brazil.
authors.forename: Andréia da Silva
authors.initials: Ada S
authors.lastname: Fernandes
authors.affiliation: Department of Biophysics and Biometry, Institute of Biology Roberto Alcantara Gomes, Rio de Janeiro State University, Rio de Janeiro, Brazil.
authors.forename: Alexandre Santos
authors.initials: AS
authors.lastname: Alencar
authors.affiliation: Department of Biophysics and Biometry, Institute of Biology Roberto Alcantara Gomes, Rio de Janeiro State University, Rio de Janeiro, Brazil.
authors.forename: Heitor
authors.initials: H
authors.lastname: Evangelista
authors.affiliation: Platform of Analytical Chemistry, Farmanguinhos, Oswaldo Cruz Foundation, Rio de Janeiro, Brazil.
authors.forename: José Luiz
authors.initials: JL
authors.lastname: Mazzei
authors.affiliation: Department of Biophysics and Biometry, Institute of Biology Roberto Alcantara Gomes, Rio de Janeiro State University, Rio de Janeiro, Brazil.
authors.forename: Israel
authors.initials: I
authors.lastname: Felzenszwalb
keywords: Moss; mutagenicity; photoprotection; sun protection factor; thymine-dimer inhibition