Búsqueda de bacterias marinas como fuente de inhibidores de quorum sensing (IQS): primer estudio químico de Oceanobacillus profundus (RKHC-62B) / Screening of marine bacterial strains as source of quorum sensing inhibitors (QSI): first chemical study of Oceanobacillus profundus (RKHC-62B)

Antecedentes: Los productos naturales aislados de microorganismos marinos han demostrado tener un amplio rango de actividades biológicas incluyendo inhibidores de quorum sensing. Objetivos: Estudiamos quince cepas bacterianas del phylum Firmicutes aisladas del coral blando Antillogorgia elisabethae que fueron evaluadas como una nueva fuente sostenible de compuestos inhibidores de quorum sensing (IQS). Métodos: Se prepararon cultivos en cuatro medios diferentes y extraídos usando una resina no iónica. Todos los extractos fueron probados con el fin de establecer su actividad inhibitoria de quorum sensing (IQS) usando Chromobacterium violaceum ATCC 31532 como biosensor. Los extractos activos fueron fraccionados mediante cartuchos RP-18. Cada fracción fue evaluada mediante bioensayo y analizada por HPLC. Resultados: Las fracciones metanólicas de Jeotgalicoccus halophilus y Oceanobacillus profundus fueron las más activas, lo cual sugiere que los compuestos no polares pueden ser los responsables de esta actividad. Conclusiones: El estudio químico del extracto orgánico de O. profundus cultivado en medio LBS permitió aislar los compuestos tirosol (1) y acetato de tirosol (2) como los responsables de la actividad IQS.

Background: Natural products isolated from marine microorganisms have demonstrated a wide range of biological activities included quorum sensing inhibitors. Objectives: We study fifteen marine Firmicutes bacterial strains isolated from the Caribbean soft coral Antillogorgia elisabethae that were evaluated as a novel and sustainable source of quorum sensing inhibitor compounds. Methods: Cultures were made in four different culture media and further extracted using a non-ionic resin. All these extracts were tested in order to establish its quorum sensing inhibition (QSI) activity using Chromobacterium violaceum ATCC 31532. The active extracts were fractionated by RP-18 cartridge. Each fraction was tested and evaluated for its composition by HPLC-PDA. Results: Methanol fractions of Jeotgalicoccus halophilus and Oceanobacillus profundus were the most active ones, suggesting that non-polar compounds could be the responsible for the QSI activity of the bacterial extracts here tested. Conclusions: The chemical study of the organic extract of Oceanobacillus profundus cultured in LBS, yielded the compounds tyrosol (1) and tyrosol acetate (2) as responsible of QSI activity showed by the organic extract.

Marine organisms as source of extracts to disrupt bacterial communication: bioguided isolation and identification of quorum sensing inhibitors from Ircinia felix

AbstractIn this study, 39 extracts from marine organisms were evaluated as quorum sensing inhibitors, collected in the Colombian Caribbean Sea and the Brazilian Coast including 26 sponges, seven soft corals, five algae and one zooanthid. The results showed that crude extracts from the soft coral Eunicea laciniata, and the sponges Svenzea tubulosa, Ircinia felix and Neopetrosia carbonaria were the most promising source of quorum sensing inhibitors compounds without affecting bacterial growth, unlike the raw extracts of Agelas citrina, Agelas tubulata, Iotrochota arenosa, Topsentia ophiraphidites, Niphates caycedoi, Cliona tenuis, Ptilocaulis walpersi, Petrosia pellasarca, and the algae Laurencia catarinensis and Laurencia obtusa, which displayed potent antibacterial activity against the biosensors employed. The crude extract from the sponge I. felix was fractionated, obtaining furanosesterterpenes which were identified and evaluated as quorum sensing inhibitors, showing a moderate activity without affecting the biosensor's growth.

Antiherpes screening of marine organisms from Colombian Caribbean Sea

The exploration of marine environment represents a promising strategy in the search for new active antiviral compounds. The isolation and characterization of the nucleosides spongothymidine and spongouridine from the sponge Cryptotethia crypta used as models for the synthesis of ara-A (vidarabine), that has been used therapeutically against herpetic encephalitis, was the most important contribution since the late 1970s. This paper describes the in vitro antiviral evaluation of 26 organic extracts obtained from eleven octocoral species and fifteen marine sponges. Cytotoxicity was evaluated on Vero cells by MTT assay and the antiviral activity was tested against Herpes Simplex Virus type 1 (HSV-1, KOS strain) by plaque number reduction assay. Results were expressed as 50 percent cytotoxic (CC50) and 50 percent inhibitory (IC50) concentrations, respectively, in order to calculate the selectivity index (SI= CC50/IC50) of each extract. Among the tested marine octocoral species, only three extracts showed antiviral activity, but with low selectivity indices (<3.0). Among the tested marine sponges, eight extracts showed SI values higher than 2.0, and three can be considered promising (Aka cachacrouense, Niphates erecta and Dragmacidon reticulatum) with SI values of 5.0, 8.0 and 11.7, respectively, meriting complementary studies in order to identify the bioactive components of these sponge extracts, which are in course now.

COMPOSICIÓN QUÍMICA Y ACTIVIDAD ANTIFOULING DE LA FRACCIÓN LIPÍDICA DE LA ESPONJA MARINA Cliona tenuis (Clionidae) / CHEMICAL COMPOSITION AND ANTIFOULING ACTIVITY OF THE LIPID FRACTION OF THE CARIBBEAN MARINE SPONGE Cliona tenuis (Clionidae) / COMPOSIÇÃO QUÍMICA E PROPRIEDADES ANTIFOULING DA FRAÇÃO LIPÍDICA DA ESPONJA MARINHA Cliona tenuis (Clionidae)

Del extracto orgánico de la esponja marina Cliona tenuis, recolectada en las Islas del Rosario (Colombia, mar Caribe), fue obtenida la fracción lipídica, la cual presentó propiedades antifouling en pruebas en campo. Esta fracción fue separada por CC sobre gel de sílice hasta obtener fracciones de ésteres metílicos, glicéridos, glicolípidos, fosfolípidos y ácidos grasos libres, las cuales fueron identificadas por CCD y técnicas de de-replicación (RMN 1H y 13C). Posteriormente, las fracciones de glicéridos, glicolípidos y fosfolípidos fueron hidrolizadas, y los ácidos obtenidos, junto con los provenientes de la fracción de ácidos grasos libres, fueron transformados en ésteres metílicos, y todos se analizaron por CGAR-EM. Para ubicar las insaturaciones y ramificaciones, los ésteres metílicos se transformaron luego en sus correspondientes pirrolididas, las cuales también se analizaron por CGAR-EM. El estudio cromatográfico (valores de ECL) y de los espectros de masas de los ésteres metílicos y de sus derivados pirrolididas permitió identificar 81 ácidos grasos diferentes, de los cuales no habían sido previamente reportados: los ácidos 4,8-hexadecadienoico, 11-metil- 4,10-octadecadienoico, 6,9,12,14- icosatetraenoico, y 6,9,12,14,17-icosapentanoico.

The lipid fraction obtained from the marine sponge Cliona tenuis, collected at the Islas del Rosario (Colombia, Caribbean Sea), showed antifouling activity using field bioassays. This fraction was separated by CC on silica gel obtaining a mixture of methyl esters, and enriched fractions of glycerides, glycolipids, phospholipids and free fatty acids. All of them were identified by TLC and dereplication techniques (NMR). The glyceride, glycolipid, and phospholipid fractions were hydrolyzed and the fatty acids obtained, together with the initial fatty acids fraction, were converted into their methyl esters and analyzed by HRGC-MS. To locate unsaturations and alkyl branches in fatty acids, their methyl esters derivates were transformed to pyrrolidides and subsequently analyzed by HRGC-MS. The identity of the fatty acids was carried out using their ECL value as methyl esters, and particularly the study of their pirrolidide spectra was used to locate unsaturations and alkyl branch positions. This study allowed us to identify 81 fatty acids, four of them never reported before: 4,8-hexadecadienoic acid, 11-methy l-4, 10-octadecadienoic acid, 6,9,12,14-icosatetraenoic acid, and 6,9,12,14,17-icosapentanoic acid.

A partir do extrato orgânico da esponja marinha Cliona tenuis, coletada nas ilhas do Rosario (Colombia, Mar Caribe), foi obtido uma fração lipídica, que apresentou propriedades antifouling in situ. Esta fração foi separada através de CC em gel de sílica para obter as frações de ésteres metílicos, glicerídeos, glicolipídeos, folfolipídeos e ácidos libres, as quais foram identificadas por CCD e técnicas espectroscópicas de RMN 1H e 13C. Posteriormente, as frações contendo glicerídeos, glicolipídeos e folfolipídeos foram hidrolizadas e os ácidos obtidos, juntamente com os ácidos obtidos das frações que continham ácidos livres foram transformadas em ésteres metílicos e analisados por CGAR-EM. Para identificar as insaturações e ramificações, os ésteres metílicos foram transformados em derivados pirrolidínicos para serem analisadas por CG-EM. Através da análise cromatográfica (valores de ECL) e dos espectros de massas dos ésteres metílicos e seus derivados pirrolidínicos foi possível identificar 81 ácidos graxos diferentes, sendo que quatro são compostos ainda não relatados: os ácidos 4,8-hexadecadienóico, 11-metil-4,10-octadecadienóico, 6,9, 12, 14- icosatetraenóico, e 6,9,12,14,17-icosapentanóico.

APROXIMACIÓN AL ESTUDIO DE LA INTERACCIÓN ENTRE Aristolochia maxima Y LARVAS DE LAS MARIPOSAS Battus polydamas polydamas Y Parides panares erythrus MEDIADA POR ÁCIDOS ARISTOLÓQUICOS / Approach to the Interaction Studies of Aristolochia maxima and the Caterpillars of Butterflies Battus polydamas polydamas and Parides panares erythrus

Las mariposas de la tribu Troidini (Lepidoptera: Papilionidae) capturan los ácidos aristolóquicos (AAs) provenientes de su alimentación larval en plantas de Aristolochiaceae para su protección. En este estudio se detectó la presencia de los ácidos aristóloquicos I y II (AAI y AAII) en hojas jóvenes de Aristolochia maxima (Aristolochiaceae) y en larvas de las mariposas Battus polydamas polydamas y Parides panares erythrus (Papilionidae, Papilioninae) por Cromatografía Líquida de Alta Eficiencia (CLAE). De acuerdo con los resultados de los perfiles cromatógraficos por CLAE, el AAI fue el ácido aristolóquico mayoritario encontrado tanto en las larvas como en las hojas jóvenes de la planta, seguido por cantidades menores del AAII. Estos resultados permiten afirmar que la interacción plantaanimal entre las mariposas de las especies B. polydamas y P. panares y las plantas de A. maxima, está mediada, por los ácidos aristóloquicos I y II.

Most butterflies of the tribe Troidini (Lepidoptera: Papilionidae) sequester aristolochic acids (AA) for their protection. These acids are derived from their host plants family Aristolochiaceae upon which they feed on during their larval stages. Using analytical High Performance Liquid Chromatography (HPLC) methods we were able to detect the presence of aristolochic acids I and II both in the young leaves of Aristolochia maxima (Aristolochiaceae) and in the caterpillars of the butterflies Battus polydamas polydamas and Parides panares erythrus (Papilionidae, Papilioninae). Aristolochic acid I was the major constituent found, followed by lesser amounts of Aristoloquic acid II. These results confirm that the hostanimal interaction among butterflies of the studied species and A. maxima plants is mediated, by aristolochic acids.