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MEDIR-OP, a Mediterranean directory for operational oceanography developed within the MAMA. Project

Chitin of poriferan origin is a unique and thermostable biological material. It also represents an example of a renewable materials source due to the high regeneration ability of Aplysina sponges under marine ranching conditions. Chitinous scaffolds isolated from the skeleton of the marine sponge Aplysina aerophoba were used as a template for the in vitro formation of Fe2O3 under conditions (pH similar to 1.5, 90 degrees C) which are extreme for biological materials. Novel chitin-Fe2O3 three dimensional composites, which have been prepared for the first time using hydrothermal synthesis, were thoroughly characterized using numerous analytical methods including Raman spectroscopy, XPS, XRD, electron diffraction and HR-TEM. We demonstrate the growth of uniform Fe2O3 nanocrystals into the nanostructured chitin substrate and propose a possible mechanism of chitin-hematite interactions. Moreover, we show that composites made of sponge chitin-Fe2O3 hybrid materials with active carbon can be successfully used as electrode materials for electrochemical capacitors.

Chitin is known to adsorb various metals. Therefore, chitin containing materials are taken into consideration as filter materials for contaminated waters. Marine sponges of the order Verongida form three-dimensional networks of fibrous chitin, which can easily be extracted. In the hydrated state, these networks are flexible, mechanically stable and can be cut or pressed into any desired form. Here, we show for the first time that chitin-based networks of sponge origin are useful for effective uranium adsorption. They adsorb U(VI) from solution with a higher sorption capacity than many other chitinous sorbents from fungal biomass. Solid-state NMR, infrared and Raman spectroscopy indicated that the U(VI) is bound to the chitin by weak interactions such as hydrogen bonds. 90 % of the U(VI) could be desorbed using diluted hydrochloric acid. Uranium adsorption and desorption did not result in any destruction of the chitin material.

The sterol composition of two green algae and two brown algae from the South Adriatic was determined. In the green alga Ulva lactuca, the principal sterols, were cholesterol and isofucosterol. In the brown alga Cystoseira adriatica, the main sterols were cholesterol and stigmast-5-en-3 beta-ol, while the characteristic sterol of the brown algae, fucosterol, was found only in low concentration. The sterol fractions of the green alga Codium dichotomum and the brown alga Fucus virsoides contained practically only one sterol each, comprising more than 90 % of the total sterols (clerosterol in the former and fucoserol in the latter). Određen je sastav sterolne smese dve zelene i dve mrke alge iz južnog Jadrana. U zelenoj algi Ulva lactuca glavni steroli su holesterol i izofukosterol. U mrkoj algi Cystoseira adriatica glavni steroli su holesterol i stigmast-5-en-3ß-ol, dok je fukosterol, sterol karakterističan za mrke alge, nađen samo u maloj količini. Sterolne smese zelene alge Codium dichotomum i mrke alge Fucus virsoides sastoje se praktično samo od po jednog sterola, klerosterola u prvoj i fukosterola u drugoj, koji sačinjavaju više od 90 % sterolnih frakcija.

Sustainable development requires the intelligent management of the marine environment, to protect the marine ecosystem, minimise the impacts of climate change and anthropogenic influences, and provide benefits for a wide range of users. Routine ocean monitoring and forecasting based on sound science, long term and adaptive monitoring,, and co-operation between nations, is the main tool for such a management. The assets and needs of all countries have to be identified, as well as the constraints impeding data exchange and marine observations in the EEZs. The challenge is to build a monitoring system based on up-to-date science and technology, and adapted to the specificity of the basin for the benefit of different users in all Mediterranean countries. It is necessary to involve all riparian countries in the process of building the Mediterranean monitoring system. A strengthened and dedicated link between the scientific community and the public authorities is moreover necessary to provide a sound scientific background for policy decisions based on environmental monitoring. Building on these concepts the Mediterranean network to Assess and upgrade the Monitoring and forecasting Activity in the region (MAMA), funded under the EESD Programme of the 5th FP, and involving partners from all the Mediterranean countries, aims to establish the multi-national network that will prepare the institutional linkages and regional platform for such an integrated and sustained monitoring system in the region. The project builds on the trans-national pooling of scientific and technological resources and provides a concerted basin-scale effort towards the planning and design of the initial ocean observing system in the Mediterranean. The system-wide approach of MAMA is expected to trigger an enhanced motivation on the relevance of systematic marine observations for the sustainable and shared use of the marine resources of the Mediterranean Sea. These catalytic ingredients constitute the thrust of MAMA and an enabling asset to the future projection into long-term commitments at governmental level.

Three marine invertebrate FITC-labelled lectins, CNL, GCL, and GSL, isolated respectively, from the sponges Chondrilla nucula, Geodia cydonium, and the hexacoral Gerardia savaglia, were used as potential diagnostic tools for different breast tumors. The lectins vary in their carbohydrate binding properties: GSL is D-mannose specific, GCL and CNL D-galactose specific. GSL labels most investigated types of malignant tissues distinctively, while the results with CNL and GC-L are less consistent. The well known D-mannose specific lectin, concanavalin A, also binds to tumor tissues, but with much lower intensity than GSL.

In the present work, we describe a novel lectin which is specific for poly-N-acetyllactosamine sequences on complex N- and O-linked carbohydrate chains. This lectin was extracted and purified from the algae Udotea petiolata. The purified lectin is a monomer with a molecular mass of 65,000 and an isoelectric point of 5.6. It agglutinates normal, neuraminidase and protease-treated erythrocytes from humans irrespectively of the blood group (A, B and O) and animal erythrocytes. The Udotea lectin displays a strong mitogenic effect on human lymphocytes, especially T-cells. This lectin binds to the human serum plasma protein 8S alpha 3-glycoprotein with high affinity (ID50 0.02 microM); other species of human serum glycoproteins exhibiting a similar preponderance of complex type N-glycosylation showed also high binding capacities in the order 9.5 S alpha 1-glycoprotein greater than alpha 2-macroglobulin = beta 2 glycoprotein = immunoglobulin A greater than asialofetuin greater than alpha 1-acid glycoprotein and mucin glycopeptide (from amnion fluid). Monosaccharides and disaccharides tested do not bind to the lectin. This novel lectin will be useful for identification of N- and O-linked glycans rich in poly-N-acetyllactosamine.