14200-67-0Relevant articles and documents
Catalytic Depolymerization of Chitin with Retention of N-Acetyl Group
Yabushita, Mizuho,Kobayashi, Hirokazu,Kuroki, Kyoichi,Ito, Shogo,Fukuoka, Atsushi
, p. 3760 - 3763 (2015/12/08)
Chitin, a polymer of N-acetylglucosamine units with β-1,4-glycosidic linkages, is the most abundant marine biomass. Chitin monomers containing N-acetyl groups are useful precursors to various fine chemicals and medicines. However, the selective conversion of robust chitin to N-acetylated monomers currently requires a large excess of acid or a long reaction time, which limits its application. We demonstrate a fast catalytic transformation of chitin to monomers with retention of N-acetyl groups by combining mechanochemistry and homogeneous catalysis. Mechanical-force-assisted depolymerization of chitin with a catalytic amount of H2SO4 gave soluble short-chain oligomers. Subsequent hydrolysis of the ball-milled sample provided N-acetylglucosamine in 53 % yield, and methanolysis afforded 1-O-methyl-N-acetylglucosamine in yields of up to 70 %. Our process can greatly reduce the use of acid compared to the conventional process.
An ammonium sulfate sensitive chitinase from Streptomyces sp. CS501
Rahman, Md. Arifur,Choi, Yun Hee,Pradeep,Yoo, Jin Cheol
, p. 1522 - 1529 (2015/03/30)
A chitinase from Streptomyces sp. CS501 was isolated from the Korean soil sample, purified by single-step chromatography, and biochemically characterized. The extracellular chitinase (Ch501) was purified to 4.60 fold with yield of 28.74 % using Sepharose Cl-6B column. The molecular mass of Ch501 was approximately 43 kDa as estimated by SDS-PAGE and zymography. The enzyme (Ch501) was found to be stable over a broad pH range (5.0-10.0) and temperature (up to 50 °C), and have an optimum temperature of 60 °C. N-terminal sequence of Ch501 was AAYDDAAAAA. Intriguingly, Ch501 was highly sensitive to ammonium sulfate but it's completely suppressed activity was recovered after desalting out. TLC analysis of Ch501 showed the production of N-acetyl d-glucosamine (GlcNAc) and Diacetylchitobiose (GlcNAc)2, as a principal hydrolyzed product. Ch501 shows antifungal activity against Fusarium solani and Aspergillus brasiliensis, which can be used for the biological control of fungus. As has been simple in purification, stable in a broad range of pH, ability to produce oligosaccharides, and antifungal activity showed that Ch501 has potential applications in industries as for chitooligosaccharides production used as prebiotics and/or for the biological control of plant pathogens in agriculture.
Development of innovative technologies to decrease the environmental burdens associated with using chitin as a biomass resource: Mechanochemical grinding and enzymatic degradation
Nakagawa, Yuko S.,Oyama, Yasuhiro,Kon, Nobuko,Nikaido, Mitsuru,Tanno, Koichi,Kogawa, Jun,Inomata, Shoji,Masui, Ayano,Yamamura, Akihiro,Kawaguchi, Mitsuaki,Matahira, Yoshiharu,Totani, Kazuhide
experimental part, p. 1843 - 1849 (2011/09/14)
The production of N-acetylglucosamine (GlcNAc, chitin monosaccharide) from crab or shrimp shells generally requires numerous steps and the use of deleterious substances. One goal for researchers is the direct production of GlcNAc and NN′-diacetylchitobiose [(GlcNAc)2, chitin structural dimeric unit] from both chitin and crab shells. The present study reports the development of an intensive ball "converge" mill for the rapid mechanochemical conversion of chitin or crab shells into amorphous, chitinase-sensitive microparticles. Optimal crab shell grinding parameters were determined, and close to 100% direct degradation of chitin from crab shell to GlcNAc was achieved. This is the first report of using a mechanochemical process with enzymatic degradation to decrease the environmental burdens associated with GlcNAc production from chitin.
