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

국문 초록 (Abstract)

매미 허물로부터 화학적 처리법으로 키틴을 분리하고 그 물리화학적 특성을 조사하였다. 얻어진 키틴은 백색의 분말 형태였으며 그 수율은 31.7%였다. 매미 키틴은 30℃에서 진한 염산 가수분해 반응으로 올리고당으로 분해되었으며, 반응시간에 따라 키틴의 분해율은 증가하여 24시간에는 44.0%의 분해율을 기록하였다. GlcNAc1-3의 함량 비율은 반응 0.5시간에 66.5%, 반응 12시간에는 84.4%로 증가하였다. 반응 24시간에는 단당 GlcNAc의 함량이 79.4%를 차지하였으며, 4당 이상은 검출되지 않았다. 매미허물 키틴은 게, 새우 키틴과 같은 형태의 FT-IR 스펙트럼 양상이 나타나 α-chitin으로 확인되었고, 아세틸화도는 88.1%로 조사되었다. 매미 허물 키틴의 X-선 회절 분석결과 2θ = 9.4˚, 19.4˚에서 면간격이 9.39 Å와 4.60 Å로 각각 측정되었으며, 결정화도 및 결정크기의 값은 각각 81.9%, 4.6 nm로 α-chitin인 게, 새우 키틴의 특성치와 유사하였다.

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%.