Properties of chitin isolated from two economically important storage pests, Tribolium castaneum and Sitophilus oryzae

In the present study, we extracted and characterized chitin of two storage pests, Tribolium castaneum and Sitophilus oryzae and compared their physicochemical properties with commercial shrimp chitin. For the characterization, we performed Fourier transform infrared spectroscopy (FT-IR), X-ray diffractometry (XRD), Elemental analysis (EA), reducing sugar assay, and scanning electron microscopy (SEM). The percentage of yield was 26.38% and 32.72% for T.castaneum and S.oryzae respectively. FT-IR and XRD data evaluated that the chitin is in its alpha form. The Crystalline Index (CrI 110) of chitin extracted from T. castaneum and S. oryzae were 81% and 82% and are close to that of commercial chitin of shrimp. SEM showed a porous and fibrous structure in S. oryzae whereas in T. castaneum it was planer and less porous. The degree of Acetylation (DA) values was calculated as 57.67% for T. castaneum and 123.54% for S. oryzae in accordance with the elemental content results. Reducing sugar assay results depicted that the chitin of both the insects is almost similar to commercial quality. The data obtained in current study can be used for researchers working on T. castaneum and S. oryzae .