# Marine-Originated Materials and Their Potential Use in Biomedicine
## 4 Arthropod-Originated Components and Their Biomedical Applications  
Arthropods and particularly crustaceans such as crabs, shrimps, and lobsters are a great source of calcium carbonate, silk, chitin, and chitosan [14; 15; 76]. Most of them have an outer skeleton, consisting of chitin-protein fibers and precipitated calcium carbonate within the chitin matrix for protection [77]. Applications of chitin derived from marine organisms, such as sponges, have been already mentioned. Chitosan is a polysaccharide that is obtained by the deacetylation of chitin and is available in crustaceans shells. In biomedicine, chitosan is used due to its high solubility and its active sites [73]. The wide use of chitosan in drug delivery systems and in tissue engineering are quite well known, but it is also worth mentioning the applications of chitosan in dentistry (wound healing, tissue engineering, and antimicrobial activity) [78]. Calcium carbonate is naturally available in the shells of crustaceans such as crabs and shrimps. The source of calcium is the water itself. In ocean water, the concentration of calcium is high. Thus, crustacea store calcium using a biomineralization process. Calcium \begin{table}
\begin{tabular}{c c c c} \hline \hline
**Marine-Sponge-Originated Component** & **Source** & **Application** & **Ref.** \\ \hline \multirow{4}{*}{polyphosphates} & \multirow{4}{*}{marine sponges} & biomedicine (regenerative medicine (bone repair, biomimetic performance): upregulation of collagen type I and II levels in osteogenic and chondrogenic cells in the presence of polyphosphates & [69] \\ \cline{3-4}  & & biomedicine (tissue engineering (scaffolds)): good porosity, thermostability, and mechanical strength of spongin & [71] \\ \hline \multirow{4}{*}{spongin} & \multirow{2}{*}{_Densoyonge Hippocamp_} & biomedicine (tissue engineering (scaffolds)): spongin as a template for hydrothermal deposition of crystalline titanium dioxide & [72] \\ \cline{3-4}  & & biomedicine (tissue engineering, drug delivery systems): high thermostability, biocompatibility, biodegradation, and good mechanical properties of chitin & [74] \\ \hline \multirow{4}{*}{chitin} & \multirow{2}{*}{marine sponges} & biomedicine (biosensoring, water filter): high stability of chitin even in high-temperature and high-pressure conditions & [75] \\ \cline{3-4}  & & biomedicine (tissue engineering, drug delivery systems): high thermostability, biocompatibility, biodegradation, and good mechanical properties of chitin & [74] \\ \hline \multirow{4}{*}{chitin} & \multirow{2}{*}{marine sponges} & biomedicine (biosensoring, water filter): high stability of chitin even in high-temperature and high-pressure conditions & [75] \\ \cline{3-4}  & & biomedicine (biosensoring, water filter): high stability of chitin even in high-temperature and high-pressure conditions & [75] \\ \hline \hline \end{tabular}
\end{table} 
Table 2: _Cont._  
Figure 1: The applications of marine-sponge-originated biomaterials. carbonate in their exoskeletons, acting as a biomineral, can be used in regenerative medicine to form scaffolds or 3D templates for bone repair [79]. Silk is another promising biomaterial that is found in crustacea [80, 81]. Silk is a protein-based biomaterial produced by arthropods, among other animals [81]. It has a great variety of applications, including in the textile industry and optoelectronics, due to its physicochemical and mechanical properties. The biocompatibility of silk allows its use in tissue engineering, regenerative medicine, and cosmetics. The sustainability and biodegradability of silk-based biomaterials make them desirable [76]. Silk can be used to enhance composite materials. [PERSON] et al. created a PEG-silk hydrogel mimicking the structure of cartilage [82]. Silk fibers and hyaluronic acid were used by [PERSON] et al. to develop a scaffold for biomedical use, supporting the cellular proliferation of bone marrow mesenchymal stem cells [83].