Isolation, characterization, antimicrobial and cytotoxic properties of Cydalima perspectalis silk proteins

Natural silk produced by silkworms and some arthropod spiders stands out as a traditional protein polymer. Fibroin and sericin, which are silk proteins obtained from cocoons, have been used in the medical field for centuries. This study is the first to evaluate the physicochemical properties and biological activities of these proteins, which were isolated from the boxwood moth (Cydalima perspectalis), as a biotechnological material. This followed this separation of the fibroin and sericin proteins obtained from the cocoons using a high-temperature and high-pressure method. The morphological, thermal, structural, and elemental properties of the obtained fibroin and sericin were analyzed using SEM, FTIR, TGA, XRD as well as elemental analysis. These studies were followed by biocompatibility and antimicrobial studies of the proteins. L929 (mouse fibroblast) cells were used in cytotoxicity assays, with cell viability evaluated using the MTT method. The study showed that the serine had no cytotoxic effect on NIH3T3 cells, whereas fibroin was cytotoxic for L929 cells. Fibroin surfaces exhibited antimicrobial activity by supporting the adhesion of, Staphylococcus aureus, Bacillus subtilis, Escherichia coli, and the fungus Candida albicans. This study demonstrates that silk proteins derived from other organisms can be used as alternative biomedical materials.