Extratos bio-ativos de algas marinhas na costa do Ceará: determinacao de atividade contra o vírus da dengue e bactérias patogênicas resistentes a múltiplos antimicrobianos

Abstract

Search for new compounds with antibacterial and antiviral activity has become more intense due to the increasingly frequent registration of bacterial diseases and clinical antimicrobial-resistance, besides viral infections that cause overload of public health services. Macroalgae are a large group of biologically important marine plants as a source of bioactive compounds. Antimicrobial activity of algal extracts has already been reported against bacterial strains, fungal, viral-infections and resistant-strains to antimicrobial commercially available. Thus, the aim of this research was to investigate and characterize substances present in marine macroalgae from the coast of the state of Ceará as a basis for the development of new drugs by the inhibitory action of macroalga extracts against pathogenic microorganisms (bacteria and virus) of humans and aquatic animals, considering the importance to search for new compounds with biological and therapeutic potential from macroalgae. The results obtained demonstrate antibacterial activity of macroalga extracts of Lobophora variegata, Padina gymnospora, Hypnea musciformis, Ulva fasciata, Ulva lactuca and Caulerpa prolifera against bacteria Staphylococcus aureus ATCC 25923, Escherichia coli ATCC 259222, Salmonella strains and multidrug-resistant Vibrio from marine shrimp farms. The methanolic extract of Padina gymnospora exhibited a complete inhibition of Salmonella ser biofilm. Braenderup LAMAP 18 at the concentration of 8mg/mL, however the concentrations of 0.125mg/mL to 4mg/mL had statistically significant results when compared to the negative control. The methanolic and ethanolic extracts of macroalgae presented a cytotoxic effect from the concentration of 1.05 mg/mL tested up to the concentration of 5.92 mg/mL for Vero cells. Furthermore, the extracts of Padina gymnospora (methanolic), Ulva fasciata (methanolic) and Caulerpa prolifera (methanolic and ethanolic) neutralized the dengue virus DENV-3, with results that reached 76.5%, 100%, 84.2% and 100% inhibition of the viral pathogen, respectively. Chemical characterization of macroalga extracts with some biological activity showed high percentages of palmitic, oleic and propionic acids, in addition to other minor compounds with proven antibacterial activity such as azelaic, stearic, myristic acids. Therefore, the marine algae extracts represent a source of bioactive compounds against pathogens from humans and aquatic animals.