Efeitos bioquímicos da exposição ao nanomaterial óxido de grafeno em diferentes tecidos do camarão branco (Litopenaeus vannamei; Crustacea, Decapoda), através da suplementação na ração

O desenvolvimento da nanotecnologia vem se intensificando nos últimos anos. Sendo que os NM já estão sendo utilizados em vários produtos disponíveis no mercado. Dentre os NM mais utilizados estão os compostos de carbono que embora sejam compostos somente por este elemento podem ter estruturas diferentes que refletem em suas aplicações e possivelmente em seus efeitos. Dentre os NM de carbono, o grafeno e o óxido de grafeno apresentam promissoras características que ampliam sua utilização em diversos segmentos desde eletrônicos até a distribuição de medicamentos. A intensificação da produção e utilização destes NM é acompanhada pela liberação destes nanomateriais no ambiente que pode afetar os organismos vivos, principalmente os animais aquáticos. Entretanto, pouco se sabe sobre os efeitos do óxido de grafeno em crustáceos de importância comercial como é o caso do camarão branco Litopenaeus vannamei. Portanto, a presente dissertação teve como objetivo avaliar os efeitos biológicos da exposição ao óxido de grafeno em diferentes tecidos do camarão.

The development of nanotechnology has intensified in recent years. Since the NM are already being used in several products on the market. NM Among the most used are carbon compounds that although only compounds with this element can have different structures that reflect in their applications and possibly its effects. Among the NM carbon, graphene and graphene oxide show promising features that expand its use in various segments from electronics to drug delivery. Increased production and use of these NM is accompanied by the release of nanomaterials into the environment that can affect living organisms, especially aquatic animals. However, little is known about the effects of graphene oxide in crustaceans of commercial importance such as the white shrimp Litopenaeus vannamei. Therefore, this thesis aimed to evaluate the biological effects of exposure to graphene oxide in different tissues of shrimp.

The nanomaterials (NM) of carbon as graphene oxide has being employed in several areas such as electronic and biomedicine. Consequently, with increase of use this NM there is also the bigger release into environment aquatic. However few data are available about effect in aquatic organisms. So, the objective of present study was to evaluate the effects of exposure to graphene oxide trough of diet in the shrimp Litopenaeus vannamei exposed during 4 or 6 weeks. The results showed: 1) An decrease in reactive oxygen species (ROS); 2) increase in glutamate cysteine ligase activity (GCL); 3) increase in reduced glutathione (GSH) levels and 4) increase in glutathione-S-transferase (GST) activity in gills and muscle; 5) increase in total antioxidant capacity in hepatopancreas and 6) increase in lipidic peroxidation in muscle and decrease in gills, after 4 weeks of exposure. After 6 weeks were observed: 7) increase in ROS in muscle and gills; 8) increase in GCL activity in all tissues; 9) increase in GST activity in muscle and hepatopancreas and 10) increase in total antioxidant capacity in muscle. The results suggested that graphene oxide can interfere in antioxidant response in different tissues of Litopenaeus vannamei.