RESUMO: As algas marinhas são fontes naturais de macromoléculas conhecidas como polissacarídeos sulfatados. Esta classe de compostos atraiu o interesse das Ciências Farmacêuticas devido às suas propriedades farmacológicas como anticoagulante, antiplaquetária e antitrombótica. Portanto, este estudo tem como objetivo avaliar o potencial anticoagulante de polissacarídeos sulfatados extraídos de algas de Penicillus capitatus. Os polissacarídeos sulfatados extraídos foram purificados, parcialmente caracterizados e sua atividade anticoagulante foi avaliada. O processo de extração seguido pela precipitação com etanol resultou em cinco frações. Entre as frações analisadas, F44 foi a maior concentração de polissacarídeos sulfatados. Após a purificação, as frações F23 e F44 mostraram atividade anticoagulante in vitro em um teste de tempo de tromboplastina parcialmente ativada e tempo de protrombina. Seu mecanismo preferencial é baseado nas interações entre trombina e fator Xa. Estudos adicionais sobre a estrutura farmacológica são necessários para testar a viabilidade do uso como agente terapêutico.

ABSTRACT: Marine algae are natural sources of macromolecules known as sulfated polysaccharides. This class of compounds has attracted the interest of Pharmaceutical Sciences due to its pharmacological anticoagulant, antiplatelet and antithrombotic properties. Therefore, this study evaluated the anticoagulant potential of sulfated polysaccharides extracted from the algae Penicillus capitatus. The extracted sulfated polysaccharides were purified, partially characterized and their anticoagulant activity was evaluated. The extraction process followed by ethanol precipitation resulted in five fractions. Among the analyzed fractions, F44 contained highest concentration of sulfated polysaccharides. After the purified fraction F23, F44 displayed in vitro anticoagulant activity in a time testing for activated partial thromboplastin time and prothrombin time. The preferential mechanism effect was based on interactions between thrombin and factor Xa. Additional studies on structure pharmacological are required to test the viability of the use of sulfated polysaccharides as therapeutic agents.

Organic extracts of 36 species of marine algae (sixteen species of Rhodophyta, eight species of Ochrophyta and twelve species of Chlorophyta) from seven locations on the Brazilian coast were evaluated for their anti-HSV-1 and anti-HSV-2 activity resistant to Acyclovir (ACV). Activity tests in crude extracts, followed by the identification of the major compounds present, were performed for all species. The chemical profiles of all crude extracts were obtained by ¹H-NMR and 13C-NMR spectroscopy. The percentage of extracts with antiviral activity was higher for HSV-1 (86.1%) than for HSV-2 (55.5%). The green algae Ulva fasciata and Codium decorticatum both showed the highest activity (99.9%) against HSV-1, with triacylglycerols and fatty acids as the major components. The red alga Laurencia dendroidea showed good activity against HSV-1 (97.5%) and the halogenated sesquiterpenes obtusol and (-)-elatol were identified as the major components in the extract. Against HSV-2, the green alga Penicillus capitatus (Chlorophyta) and Stypopodium zonale (Ochrophyta) were the most active (96.0 and 95.8%). Atomaric acid, a meroditerpene, was identified as the major secondary metabolite in the S. zonale extract. These results reinforce the role of seaweeds as important sources of compounds with the potential to enter into the pipeline for development of new drugs against herpes simplex.

Neste artigo, foi avaliada a atividade antiviral da alga marinha Ulva fasciata, coletada nas Praias do Forno e Rasa, em Búzios, Rio de Janeiro, Brasil, sobre a replicação do metapneumovírus humano (HMPV). Os extratos desta alga foram preparados utilizando três diferentes metodologias, visando a comparação da atividade de diferentes grupos de compostos químicos que são obtidos dependendo da metodologia empregada. Quatro, do total de seis extratos foram capazes de inibir praticamente 100% da replicação viral. Os resultados demonstram também que a maioria dos extratos (cinco, dos seis), possui atividade virucida e, portanto, possuem a habilidade de interagir com a partícula viral extracelularmente impedindo a infecção. Por outro lado, apenas dois extratos (coletado da Praia do Forno e, preparado através de maceração e maceração do decocto) foram capazes de se ligar a receptores celulares, impossibilitando assim a entrada das partículas virais nas células. Finalmente, apenas o extrato que foi preparado por maceração da alga coletada na Praia do Forno, demonstrou atividade intracelular. Até onde sabemos, este é um estudo pioneiro sobre a atividade antiviral de algas marinhas sobre o HMPV. É também o primeiro estudo sobre atividade antiviral sobre HMPV realizado no Brasil. O estudo também mostra o efeito de diferentes condições ambientais e procedimentos químicos utilizados na preparação do extrato sobre suas propriedades biológicas.

We evaluated the antiviral activity of the marine alga, Ulva fasciata, collected from Rasa beach and Forno beach, Búzios, Rio de Janeiro, Brazil on the replication of human metapneumovirus (HMPV). The algae extracts were prepared using three different methodologies to compare the activity of different groups of chemical composites obtained through these different methodologies. Four out of the six extracts inhibited nearly 100% of viral replication. The results demonstrated that the majority of the extracts (five out of six) possess virucidal activity and therefore have the ability to interact with the extracellular viral particles and prevent the infection. On the other hand, only two extracts (from Forno beach, obtained by maceration and maceration of the decoction) were able to interact with cell receptors, hindering the viral entry. Finally, only the extract of algae collected at Forno beach, obtained by maceration presented intracellular activity. To our knowledge, this is a pioneer study on antiviral activity of marine algae against HMPV. It is also the first on antiviral activity against HMPV ever done in Brazil. The study also shows the effect of different environment factors and different chemical procedures used to obtain the extract on its biological properties.