Obtaining biomaterial from invasive marine species and its potential usage in biomedical industry

In this study, five pufferfish species Lagocephalus sceleratus, L. spadiceus, L. suezensis, Sphoeroides pachygaster and Torquigener flavimaculosus, invasive lessepsian crab Charybdis longicollis and long- spiny sea urchin Diadema setosum were sampled by commercial trawling and scuba dives in Gulf of İskenderun. It is aimed to determine the usage areas of these sampled species in the biomedical industry and to bring them into the economy. In this context, hydroxyapatite was obtained from the teeth of L. sceleratus. The elemental composition of the obtained hydroxyapatite consists of 52% calcium and 39% phosphate, 2,5% manganese, 1,5% magnesium, 1% titanium, 0,8% vanadium and 3,2% other elements. The Ca/P ratio of hydroxyapatite was found to be 1,32. According to the results of the XRD analysis, it was revealed that the hydroxyapatite obtained from the L. sceleratus tooth was compatible with human teeth. Collagen and gelatin were extracted from L. sceleratus skin using the acid soluble collagen method. The rate of collagen obtained within the scope of the study was 50,9%, and the amount of gelatin was found to be 20,63%. Moisture, protein and amino acid content analyzes of the obtained collagen were made. ICP-MS was used for heavy metal accumulation analysis of soft tissues (muscle, gill, liver and brain) and teeth from pufferfish species (Lagocephalus sceleratus, L. spadiceus, L. suezensis ve T. flavimaculosus) sampled within the scope of the thesis study. According to the results obtained, metal deposits in tooth and brain tissue were similar. As a result of the studies, it was revealed for the first time that fish teeth can be used as an environmental indicator. Tissue samples were taken from the muscle, fin, skin and skeleton of L. sceleratus, T. flavimaculosus and S. pachygaster species, which were sampled within the scope of the thesis study, and mtDNA extraction was completed by using the standard phenol-chloroform method with minor modifications. The mtDNA obtained from the tissues of the species was amplified by Polymerase Chain Reaction using the Cyt b gene region. Accession numbers were obtained from Genbank with codes MZ 512179-MZ 512196 for the 18 sequences obtained. Chitin and chitosan were extracted from the shells of the Lessepsian crab C. longicollis, which were sampled within the scope of the thesis study. The rate of chitin extracted from the shells was calculated as 25,78%. The yield of chitosan produced from the extracted chitin was determined as 80.23%. As a result of FTIR and XRD analyzes, amino-polysaccharide alpha chitin containing structure was obtained as well as proteins. The characterization of the shell of D. setosum, which was sampled within the scope of the study, as revealed by FTIR and XRD methods. It shows that the reflections in the XRD analysis results overlap 91% with calcite with the chemical formula Ca5MgC6O18 and 9% with periclase chemical formula Mg4O4. Invasive alien species distributed in our country's waters have exerted pressure on native species in our waters, resulting in negative ecological and economic consequences. The fact that these species are not consumed by humans causes their numbers to increase and become dominant in the ecosystem. This thesis was revealed the areas and usage methods of this species in marine biotechnology applications and obtained economically valuable end protucts. This study was supported by the Scientific and Technological Research Council of Turkey (TUBITAK-2211/C National PhD Scholarship Program for Priority Areas), Council of Higher Education (100/2000 PhD scholarship program) and Iskenderun Technical University Scientific Research Projects Coordinatorship (2019LTB-01).