Chitin extraction and physicochemical characterization of two Buprestid beetles (<i>Chalcophora detrita</i> and <i>C. mariana</i>)

Chitins were extracted for the first time from Chalcophora detrita (Klug, 1829) and Chalcophora mariana (Linnaeus, 1758), the hardest exoskeletal insect species of the family Buprestidae (Insecta: Coleoptera). Fourier transform infrared spectrometry (FTIR) and elemental analysis confirm that isolation of chitin is successful. The chitin yields of C. detrita and C. mariana on dry basis are 28% and 26%, respectively. According to the thermogravimetric analysis (TGA) results, thermal decomposition continued up to approximately 770 degrees C in both species. The crystallinity index of the samples belonging to C. detrita and C. mariana species was determined as 91.27% and 91.61%, respectively, by X-ray diffractometer (XRD) analysis. Scanning electron microscope (SEM) was examined for surface characterization determining as fibrous for C. detrita and porous for C. mariana. Elemental analysis was performed to determine the elemental composition of the chitin, and the percentage of nitrogen was as expected for both samples. It was determined from XRD and FTIR data that both insect species examined have alpha-chitin form. These species are abundantly caught in traps set for forest pests and can therefore be considered as an alternative source of chitin.