Antibacterial bromopyrrole and other constituents from northeast brazilian Agelas sponges
bromopyrrole, anticancer, antibacterial, marine sponges, oroidin
The genus of marine sponges Agelas is a source of secondary metabolites with nitrogenous and brominated skeletons, also containing pyrrole, imidazole, terpene and amino acid moieties. Its metabolites are associated with activities such as antihistaminic, antibacterial, antifungal, cytotoxic, calcium channel modulating, antiserotonergic and antitumor, among others. In this work, distinct fractions, pre - fractionated from the methanolic extract of Agelas sp. collected on the Brazilian northeast coast, were analyzed in HPLC-MS, and the metabolites longamide B, methyl ester of longamide B, mukanadine A and E, clathramide A oroidine, 4,5-dibromo-2-carboxamide, hanishine, 9,10 dihydrokeramadine, dispacamide and hymenidine were identified. Sterols and fatty acids, obtained from the fractioning of lipid extracts and analyzed by GC-MS, were also identified. The substance 4-bromopyrrole-2-carboxamide and six other substances in structural elucidation phase were isolated. Fractions resulting from partitioning of the crude extract were tested in a microbiological assay and demonstrated antibacterial action against eight bacterial strains, such as Staphylococcus aureus, S. epidermidis, S. hominis, Enterococcus faecalis, E. faecium, Pseudomonas aeruginosa, Escherichia coli and Salmonella enteriditis. The fraction derived from acetate showed a higher antibacterial action, with MIC = 39.06 μg / ml. The fractionation and identification of the metabolites occurred through classical chromatographic techniques, GC-MS, HPLC-MS and 1H and 13C uni and bidimensional NMR.