Resumen.-Las bacterias y algas marinas son una fuente inagotable de compuestos químicos que permiten producir una amplia variedad de metabolitos secundarios bioactivos. Las bacterias marinas se han convertido en objetivo importante para la industria de la biotecnología debido a la alta cantidad de compuestos bioactivos descubierto recientemente a partir de ellas. El objetivo de este estudio fue evaluar la actividad anticancerígena y antibacteriana de extractos de las algas marinas Egregia menziesii, Codium fragile, Sargassum muticum, Endarachne binghamiae, Centroceras clavulatum y Laurencia pacifica recolectadas en Bahía Todos Santos, México. Se obtuvieron extractos orgánicos a partir de las algas libres de bacterias y de las bacterias asociadas a su superficie. Para probar la actividad antibacteriana se emplearon las cepas patógenas Staphylococcus aureus, Klebsiella pneumoniae, Proteus mirabilis y Pseudomonas aeruginosa y para la actividad anticancerígena, células de carcinoma colorectal HCT-116. De la superficie de las algas marinas se aislaron 35 cepas bacterianas que se identificaron molecularmente y pertenecían a los phyla Firmicutes, Proteobacteria, y Actinobacteria. Las cepas Cc51 aislada de Centroceras clavulatum, Sm36 aislada de Sargassum muticum, y Eb46 aislada de Endarachne binghamiae mostraron actividad anticancerígena con un IC 50 de 6,492, 5,531 y 2,843 µg ml-1 respectivamente. Asimismo, los extractos de las bacterias asociadas a las algas marinas inhibieron el crecimiento de la bacteria Gram negativa Proteus mirabilis. La actividad biológica observada en este estudio ofrece la oportunidad de un análisis químico posterior, tal como el aislamiento de los compuestos activos responsables, a fin de contribuir en el descubrimiento de nuevos fármacos.

Disorders in blood coagulation can lead to an increased risk of bleeding (hemorrhage) or clotting (thrombosis). These illnesses have increased over the last decades and no useful new substances have been discovered to remediate them. In search of new compounds from marine natural resources, macroalgae from the Northwest Mexican Pacific coast were investigated in order to detect anticoagulant activity. Egregia menziesii, Ulva neumatoidea, Porphyra perforata, Silvetia compressa, and Codium fragile were collected from Ensenada coasts. Collected materials were cleaned, dried, milled, and stored until use. Proximate chemical composition and sulfate content were determined in dried powder. Hot and cold aqueous extracts were obtained from the dried algae in order to isolate polysaccharides and similar compounds. Methanol-soluble compounds were separated by means of Soxhlet extraction. Organic and aqueous extracts were screened for anticoagulant activity in both intrinsic and extrinsic pathways of clot formation. Clotting activity was studied by standardized plasma coagulation tests (activated partial thromboplastin time (aPTT) and prothrombin time (PT)). Heparin, a sulfated glycosaminoglycan widely used in anticoagulant therapy, was used as reference. Effects were defined either as aPTT index (Sample aPTT/Control aPTT ratio) or PT index (Sample PT/Control PT ratio). Some of the fractions showed anticoagulant activity over intrinsic pathways, whereas they were found to be coagulants on the extrinsic pathway. The highest aPTT index was 1.8 for U. nematoidea (1 μg mL −1 ). Hot aqueous extracts from E. menziesii (1 μg mL −1 ) showed the highest potency, with an aPTT index of 1.4. Sulfate content and anticoagulant activity were not correlated.

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Resumen.-Se realizó el estudio de la bioactividad de las Actinobacterias cultivables a partir de sedimento marino de la Bahía de Todos Santos, México, y se identificaron mediante las secuencias del gen 16S ARNr. Las cepas bacterianas fueron cultivadas en 1 L de medio líquido A1 y se constató su crecimiento en presencia de agua de mar. Los extractos orgánicos de los cultivos se extrajeron con Amberlita XAD-7 eluida con acetona. Los extractos fueron separados por cromatografía en gel de sílice C-18. Los extractos crudos y las fracciones se probaron contra células de cáncer de colon HCT-116. En total, 26 cepas fueron cultivadas e identificadas, divididas en 10 unidades taxonómicas operacionales (UTOs) con 100% de identidad de sus secuencias, representando tres familias del orden Actinomycetales, pertenecientes a los géneros Streptomyces (77%), Micromonospora (20%) y Nocardia (3%); 6 de éstos UTOs no habían sido reportados previamente. Diecinueve por ciento de los extractos crudos del género Streptomyces mostraron actividad citotóxica en un rango de IC 50 de 69,0 a ≤ 0,076 μg·ml -1 . Las fracciones más activas contenían los compuestos monactin y derivados de pamamicina, los cuales fueron identificados por su peso molecular y sus patrones de fragmentación. Palabras clave: Bacterias marinas, actividad antitumoral, diversidad bacteriana, filogeniaAbstract.-The bioactivity of culturable Actinobacteria from marine sediment of the Todos Santos Bay, Mexico was studied, and bacteria were identified by 16S rRNA gene sequences. The strains were cultured in 1 L of culture media A1 and tested for the effects of seawater on growth. The organic components of cultures were extracted with XAD-7 amberlite and eluted with acetone. The extracts were separated by flash chromatography on C-18 silica gel. The crude extracts and the fractions were tested against colorectal cancer cells HCT-116. In total, twenty six strains were cultured and identified, divided into ten operational taxonomic units (OTUs) with 100% sequence identity, representing 3 families in the order Actinomycetales, belonging to the genus Streptomyces (77%), Micromonospora (20%) and Nocardia (3%); six of those OTUs had not been reported before. Nineteen percent of the crude extracts of the Streptomyces genus showed cytotoxic activity in a range of IC 50 of 69.0 to ≤ 0.076 μg·ml -1 . The most active fractions contained compounds identified by their molecular weight and fragmentation patterns as monactin and pamamycin derivatives.

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The bimetallic nickel-tungsten catalysts were prepared via solvothermal method. The X-ray Diffractometer (XRD) analysis revealed that the corresponding peaks at 14°, 34°, and 58° were for tungsten disulfide (WS2 ) hexagonal phase. The catalysts displayed different crystalline phase with nickel addition, and as an effect the WS2 surface area decreased from 74.7 to 2.0 m(2) g(--1) . In this sense, high-resolution transmission electron microscopy (HRTEM) showed the layers set in direction (002) with an onion-like morphology, and in the center of the particles there is a large amount of nickel contained with 6-8 layers covering it. The catalytic dehydration of 2-propanol was selective to propene in 100% at 250 °C for the sample with 0.7 of atomic ratio of Ni/Ni + W.

Two new holostan-type triterpenoid oligoglycosides, named parvimosides A (1) and B (2), were isolated from the warty sea cucumber Stichopus parvimensis (syn. Parastichopus parvimensis). Their structures and total assignments of the proton and carbon signals were established on the basis of spectral evidence, mainly 1H and 13C 1D and 2D NMR spectroscopy including DEPT, COSY, TOCSY, NOESY/ROESY, HMQC/HSQC, and HMBC experiments, as well as FABMS.

We present a simple, quick, and viable way to produce hydroxyapatite (HA) from a waste by-product of the sea food industry, this was achieved by submitting the exoskeleton of the purple sea urchin Strongylocentrotus purpuratus through a chemical reaction with H 3 PO 4 at 3 different times (3, 18, and 36 hours) with constant stirring at 35-40°C. The characterization of the materials was made by several techniques (FTIR, XRD, SEM-EDS, and TEM).The FTIR results confirmed the presence of the HA characteristic functional groups OH, PO 4 , and CO 3 , the XRD characterization showed that the synthesis of calcium phosphates such as brushite and HA was achieved by confirming the presence of its characteristic peaks, also the EDS analysis confirmed the expected HA Ca/P atomic ratio of 1.67. This work shows that we can take advantage from raw materials derived from processing sea food by giving it an added value for the biomedical industry. K E Y W O R D Sbiomaterial, FTIR, hydroxiapatite, sea urchin, Strongylocentrotus purpuratus