Biomaterial structure in deep‐sea bamboo coral (Anthozoa: Gorgonacea: Isididae): perspectives for the development of bone implants and templates for tissue engineering

Abstract Natural structural biomaterials of marine origin including mollusc shells, sponges and corals not only provide an abundant source of novel bone and cartilage replacements but also inspire investigations to develop nano‐sized biomimetic composites. This study presents a characterisation of the ultrastructure of the deep‐sea Bamboo coral (Anthozoa: Gorgonacea: Isididae) and the nanostructure of some interstitial surfaces with respect to biomineralization phenomena. The skeletons of the corals examined exhibit jointed axes of large bony calcareous structures alternated with smaller proteinaceous nodes of gorgonin, giving the skeletal remains of the organism a digitated appearance, like terrestrial bamboo. To test the hypothesis that bamboo coral internodes exhibit bone‐like mechanical and biochemical properties, structural and biochemical analyses of these natural biomineral composites and separation of proteinaceous components was performed. Due to its high potential for colonization with both human osteoblasts and osteoclasts, the organic matrix, composed of an acidic fibrillar protein framework, proved to be a very successful model for possible applications in tissue engineering. The material properties of the calcareous internodes correlate well with the material property charts for materials used in orthopedic surgery, though denser and stronger than bone. Results of the present study also clearly indicate the quinonproteinaceous nature of the gorgonin. On the basis of the high biomimetic potential of the results obtained, the use of Isididae corals as “living bone implants” as well as their biotechnological aquacultural cultivation seems to be promising for the near future.