Avaliação do potencial farmacológico dos corais invasores Tubastraea coccinea e Tubastraea tagusensis (Scleractinia, Cnidaria)

Abstract

The great diversity of species in the marine environment gives rise to compounds with unique structural patterns not found in natural products of another nature with great potential for pharmacological, cosmetic and nutritional use, among others. Corals belonging to the order Scleractinia were ignored as sources of natural products for many years, since it was not associated with the production of secondary metabolites as a defense strategy in these hard corals. The genus Tubastraea (Class Anthozoa, Order Scleractinia, Family Dendrophylliidae) is characterized as hard corals without the presence of zooxanthellae, but species of this genus present compounds with pharmacological value. This genus was first recorded on Brazilian coast at the beginning of the 21st century. The introduction of these organisms, also known as sun coral, occurred through their fouling on oil and gas platforms in Campos Basin, northern region of Rio de Janeiro state. The invasive species identified as Tubastraea coccinea and Tubastraea tagusensis were successful in their expansion process in Brazilian coast. Both species are a threat to endemic organisms from invaded regions. Recent studies of our research group have demonstrated that methanolic extracts of these corals showed anti-inflammatory activity in carrageenan-induced edema tests in mouse paws and cytotoxic and mutagenic activity for Salmonella enterica serovar Typhimurium strains. The objective of this work was to analyze the toxic and pharmacological potential of T. coccinea and T. tagusensis samples. For this purpose, methanolic, ethanolic extracts and synthesized compound from these corals were evaluated for their anti-inflammatory, mutagenic, genotoxic, cytotoxic, antiparasitic and antimicrobial ability, as well as their compositions were elucidated through chemical analysis. The high performance liquid chromatography, mass spectrometry and gas chromatography data suggest the presence of aplysinopsin analogues, a substance belonging to alkaloids class. The mutagenic and genotoxic effects were not observed in any sample tested for any concentration. Cytotoxic responses were observed for eukaryotic cells in all samples at high concentrations (500 e 5000 µg/mL). Anti-inflammatory activity was observed in all samples tested for in vivo assays, with emphasis on T. coccinea species. The ethyl acetate fraction from this sample demonstrated greater efficacy in vitro assays for anti-inflammatory activity. Samples tested for Trypanosoma cruzi toxicity showed no effect in any form of the parasite. However, the methanolic extracts showed a toxic action for the parasite Leishmania (Viannia) braziliensis. For the antimicrobial activity, the methanolic extracts showed interesting results, presenting cytotoxicity for Streptococcus pyogenes strain (8668) and being able to interfere in the biofilm formation of Staphylococcus aureus strain (ATCC 25923).