Capilliphycus salinus (CYANOBACTERIA): análise por CLAE-DAD e avaliação da inibição frente a acetilcolinesterase

Abstract

Filamentous cyanobacteria are interesting sources of bioactive compounds with biotechnological application. The species Capilliphycus salinus (Oscillatoriales:Microcoleaceae) was studied to obtain and characterize compounds of special metabolism (SM), and to evaluate the biological activity against acetylcholinesterase (AChE). The biomass was collected on the beach of Pedra do Sal, Salvador, Bahia, sorted, freeze-dried, weighed, and submitted to extraction of the MEs with 96% ethanol solvent. The hydroalcoholic extract was partitioned with the solvents hexane, ethyl acetate and distilled water and the aqueous extract was centrifuged and subjected to fractionation on a silica gel flash chromatographic column resulting in ten fractions. The fractions were monitored in thinlayer chromatography (TLC), submitted to the inhibition test against AChE with the Elmann method. Analyses by high-performance liquid chromatography coupled to diode-array (HPLCDAD), with stationary phases C18 column and chiral column with vancomycin, in ion polar mode, and mass spectrometry (MS/MS) were performed. The CCDs reacted with ninhydrin presenting maces that indicated the presence of nitrogen compounds; the AChE inhibition assay was positive for all fractions; the best chromatographic condition was with the use of the chiral column, with a temperature of 33º C and a flow rate of 0.1 mL.min-1 . The chromatograms showed peaks at different retention times and good intensity with best UVVis records at 280 nm for fraction 04, with absorbances (λmax) in regions compatible with phenolic compounds and mycosporine-like amino acids (MAAs), and at 360 nm for fraction 09, with λmax regions compatible with MAA compounds. The MS/MS analyses showed peak with ion m/z 560 in the positive mode compatible with a hybrid MAA. The results demonstrate the biotechnological potential of C. sallinus as a producer of SM.