An alternative and effective method for extracting skeletal organic matrix adapted to the red coral Corallium rubrum

Skeleton formation in corals is a biologically controlled process in which an extracellular organic matrix (OM) is entrapped inside the calcified structure. The analysis of OM requires a time-consuming and tedious extraction that includes grinding, demineralization, multiple rinsing and concentration steps. Here we present an alternative and straightforward method for the red coral Corallium rubrum that requires little equipment and saves steps. The entire skeleton is directly demineralized to produce a tractable material called ghost, which is further rinsed and melted at 80°C in water. The comparative analysis of the standard and alternative methods by electrophoresis, western blot, and FTIR of C. rubrum OM, shows that the 'alternative OM' is of higher quality. Advantages and limitations of both methods are discussed.