Isolation and identification of chitin in the black coral Parantipathes larix (Anthozoa: Cnidaria)

none16siUntil now, there is a lack of knowledge about the presence of chitin in numerous representatives of corals (Cnidaria). However, investigations concerning the chitin-based skeletal organization in different coral taxa are significant from biochemical, structural, developmental, ecological and evolutionary points of view. In this paper, we present a thorough screening for the presence of chitin within the skeletal formations of a poorly investigated Mediterranean black coral, Parantipathes larix (Esper, 1792), as a typical representative of the Schizopathidae family. Using a wide array variety of techniques (13C solid state NMR, Fourier transform infrared (FTIR), Raman, NEXAFS, Morgan-Elson assay and Calcofluor White Staining), we unambiguously show for the first time that chitin is an important component within the skeletal stalks as well as pinnules of this coral.mixedMarzia, Bo; Bavestrello, Giorgio; Denis, Kurek; Silvia, Paasch; Eike, Brunner; René, Born; Roberta, Galli; Stelling, Allison L.; Sivkov, Viktor N.; Petrova, Olga V.; Denis, Vyalikh; Kurt, Kummer; Molodtsov, Serguei L.; Dorota, Nowak; Jakub, Nowak; Hermann, EhrlichBo, Marzia; Bavestrello, Giorgio; Denis, Kurek; Silvia, Paasch; Eike, Brunner; René, Born; Roberta, Galli; Allison L., Stelling; Viktor N., Sivkov; Olga V., Petrova; Denis, Vyalikh; Kurt, Kummer; Serguei L., Molodtsov; Dorota, Nowak; Jakub, Nowak; Hermann, Ehrlic

Synthesis of nanostructured chitin-hematite composites under extreme biomimetic conditions

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

Extreme biomimetic approach for development of novel chitin GeO2 nanocomposites with photoluminescent properties

This work presents an extreme biomimetics route for the creation of nanostructured biocomposites utilizing a chitinous template of poriferan origin. The specific thermal stability of the nanostructured chitinous template allowed for the formation under hydrothermal conditions of a novel germanium oxide-chitin composite with a defined nanoscale structure. Using a variety of analytical techniques (FTIR, Raman, energy dispersive X-ray (EDX), near-edge X-ray absorption fine structure (NEXAFS), and photoluminescence (PL) spectroscopy, EDS-mapping, selected area for the electron diffraction pattern (SAEDP), and transmission electron microscopy (TEM)), we showed that this bioorganic scaffold induces the growth of $GeO_{2}$ nanocrystals with a narrow (150–300 nm) size distribution and predominantly hexagonal phase, demonstrating the chitin template’s control over the crystal morphology. The formed $GeO_{2}$–chitin composite showed several specific physical properties, such as a striking enhancement in photoluminescence exceeding values previously reported in $GeO_{2}$-based biomaterials. These data demonstrate the potential of extreme biomimetics for developing new-generation nanostructured materials