title: Further report of the occurrence of tetrodotoxin and new analogues in the Anuran family Brachycephalidae.
abstract: Tetrodotoxin (TTX) is one of the most potent toxin already isolated, which occurs in a wide range of marine as well as terrestrial animals such as in newts and anurans. In this work, the occurrence of TTX and analogues was examined in three brachycephalid species: Brachycephalus ephippium, B. nodoterga and B. pernix using LC-FLD and LC-MS/MS. In toxicity assay (intra-peritonial injection in mice) B. nodoterga extracts were non-toxic, while B. pernix extract exhibit the highest toxicity among the studied species. Skin showed the highest toxic, followed by the liver. Retention time data in the LC-FLD system indicated the presence of TTX, 4-epiTTX, 4,9-anhydroTTX and TDA, SIM data confirmed the presence of these compounds and revealed other analogs such as 11-norTTX-6(S)-ol, 5-deoxyTTX, 11-deoxyTTX, 11-oxoTTX, 6-epiTTX. Two new components were also identified by mass spectrometry (348 and 330Da). These unknown compounds have daughter ions similar to TTX, suggesting new putative TTX analogues.
authors.affiliation: Laboratório de Toxinologia, Departamento de Ciências Fisiológicas, Instituto de Ciências Biológicas, Universidade de Brasília, Brasília, DF, 70910-900, Brazil. osmindo@unb.br
authors.forename: Osmindo R
authors.initials: OR
authors.lastname: Pires
authors.forename: Antonio
authors.initials: A
authors.lastname: Sebben
authors.forename: Elisabeth F
authors.initials: EF
authors.lastname: Schwartz
authors.forename: Rodrigo A V
authors.initials: RA
authors.lastname: Morales
authors.forename: Carlos
authors.initials: C
authors.lastname: Bloch
authors.forename: Carlos A
authors.initials: CA
authors.lastname: Schwartz
mesh_terms: D000664:Amphibian Venoms / Q000737:chemistry* / Q000633:toxicity; D000818:Animals; D001001:Anura / Q000502:physiology*; D004305:Dose-Response Relationship, Drug; D051379:Mice; D015394:Molecular Structure; D013779:Tetrodotoxin / Q000031:analogs & derivatives* / Q000302:isolation & purification* / Q000633:toxicity
chemical_list: D000664:Amphibian Venoms; D013779:Tetrodotoxin