매미허물에서 분리한 키틴의 물리화학적 특성 = Physicochemical Characteristics of the Chitin Isolated from Cicadae Periostracum

다국어 초록 (Multilingual Abstract)

In this study, the physicochemical properties of the chitin isolated from cicadae (Platypleura kaempferi) periostracum was investigated. The prepared chitin was white flake form and the yield was 31.7%. The chitin was degraded into oligosaccharide during acid hydrolysis at 30℃ with concentrated HCl. The hydrolysis rate was 6.8% only after 0.5 h reaction, but increased to 44.0% after 24 h reaction. In distribution of the oligosaccharides in the hydrolyzates, ratio of GlcNAc1-3 content increased from 66.5% after 0.5 h reaction to 84.4% after 12 h reaction. The ratio of monomer GlcNAc content was 79.4% after 24 h reaction and no oligosaccharides bigger than GlcNAc4 was detected. It is found that cicadae periostracum chitin belongs to α-chitin resulting from the FT-IR spectra similar with those of crab and shrimp chitins. In X-ray diffractometer, two peaks were exhibited at 2θ = 9.5˚ (interplanar distance: 9.36Å) and 2θ = 19.4o(4.58Å). The crystallinity index and crystal size of the chitin were determined to be 81.9% and 4.6 nm, respectively, which are similar with those of crab and shrimp chitins, again confirming that cicadae periostracum chitin belongs to α-chitin. The degree of acetylation of cicadae periostracum chitin was calculated to be 88.1%.