• Journal of Life Science
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• 제9권1호
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• pp.69-80
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• 1999

Some trials to alter the structure of extracellular polysaccharides by means of biotransformation and microbial modification have been reported. Seaweed alginate was acetylated by intact and resting cells of Pseudomonas syringae ATCC 19304. Glucose analogs such as 3-O-methyl-D-glucose used as sole carbon sources was directly incorporated into curdlan by agrobacterium sp. ATCC 31749. The 2-amino-2-deoxy-D-glucose (glucosamine)and 2-acetamido-2-deoxy-D-glucose (N-acetylglucosamine) were incorporated into microbial cellulose by Acetobacter xylinum ATCC 10245. The changed monomeric composition in pullulan by Aureobasidium pullulans ATCC 42023 as well as zooglan by Zoogoea ramigera ATCC 25935 was another effect of glucose analogs used a carbon source. There was no effect of glucose analogs found in polysacharide-7 (PS-7) produced by Beijerinckia indica. ATCC 21423.

• 한국염색가공학회지
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• 제31권4호
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• pp.225-232
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• 2019

The colorants of kale powders were optimally extracted using an 1:1 mixture solvent of ethanol and DMSO at 105℃ for 30 minutes obtaining a high yield of 359.7㎍/mL chlorophylls. Low color fastness of the dyed fabrics with the extracts, particularly against washing and solar radiation, can be overcome by the combined treatments of chitosan, heat setting and tannic acid. Washing fastness to color change was improved from rating 1-2 up to 5 due to the enhanced electrostatic interactions between the colorants and the positive glucosamine unit of the chitosan in the cationized cotton. In addition, the tannic acid treatment contributed to the additional increase in color fastness after the sequential treatments of chitosan pretreatment, dyeing and heat setting.

• 한국미생물생명공학회:학술대회논문집
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• 한국미생물생명공학회 1978년도 추계학술대회
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• pp.208.4-209
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• 1978

The Chitinase which hydrolyzes the chitin, $\beta-1,$ 4-polymer of N-acetyl glucosamine, was purified from the culture broth of Streptomyces sp. 115-5 strain. The homogeneity of enzyme was reveali by CM-Sephadex C-50 column chromatography and polyacrylamide gel electrophoresis. The purified enzyme hydrolyzed chitin and chitosan, but not cellulose. And with chitin as the substrate, a Km value of 3.6mg per ml and a Vmax of $100\mu$ mole per hr were found. The activation energy for the reaction was 3.66 Kcal per mole. The M. W. was estimated 56,000 daltons, and PI as 3.0. The chitinase was inhibited by the addition of glucose, glucuronic acid, sorbitol and xylose as product inhibitors and its inhibition pattern by glucose was estimated pure competitive type.

• Journal of Microbiology and Biotechnology
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• 제11권2호
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• pp.281-286
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• 2001

Since the number of amino groups which are exposed by deacetylation of acetyl-D-glucosamine influences antimicrobial activity, a chitosan oligosaccharide (COS) derivative by N-conjugation of COS with asparagine, an amino acid with two amino groups, was synthesized and the antimicrobial effect on E. coli growth was compared with other COS derivatives which were N-conjugated with glycine, alanine, aspartic acid, cysteins, an methionine, and unmodified COS. The structure of asparagine N-conjugated COS (Asn-COS) derivative was identified by using a FT-IR, $^{13}C\;FT-NMR$, and an elemental analyzer. The antimicrobial activity of Asn-COS against E. coli growth was significantly improved as compared to the other COS derivatives as well as COS itself. This means that Asn-COS with two positive charges strongly interacts with the carboxyl negative charges on the bacteria cell wall. The results for Asn-COS were as follows: 100% bactericidal activity, 0.002% MIC, and no growth of E. coli during 3 days of culture time, suggesting that Asn-COS may be useful as a new antibiotic agent.

• Journal of Microbiology and Biotechnology
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• 제10권2호
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• pp.208-214
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• 2000

A bacterial strain producing extracellular chitosanase was isolated from crab shells and identified as a member of the genus Aureobacterium The production of chitosanase was proportionally related to the microbial growth, induced by the presence of chitosan, and repressed by glucose at 0.5% (w/v) concentration or higher. The optimal culture conditions for the production of chitosase were 3$0^{\circ}C$ and pH 7.0. Among the nitrogen sources tested, incubation with 0.25% (w/v) concentrations of tryptone and casitione showed the best production of chitosanase. The chitosanase of Aureobacterium sp. YL produced chitobiose as a major product and glucosamine, chitotriose, chitotetraose, and chitopentaose as minor products from chitosan.

• 대한약학회:학술대회논문집
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• 대한약학회 2002년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2
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• pp.246.2-247
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• 2002

In this study. we tried to investigate whether polymerized basic amino acid e.g. poly-L-lysine(PLL) which has the molecular weight under 10 kD significantly affects the physiological and stimulated mucin release from cultured hamster tracheal surface epithelial cells. Confluent primary hamster tracheal surface epithelial(HTSE) cells were metabolically radiolabeled with 3H-glucosamine for 24 hr and chased for 30 min in the presence of either PLLs or adenosine triphosphate(ATP) and PLL to assess the effects on basic or ATP-stimulated 3H-mucin release. (omitted)

• 한국섬유공학회:학술대회논문집
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• 한국섬유공학회 1998년도 봄 학술발표회 논문집
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• pp.329-333
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• 1998

The major classes of antimicrobial agents for textiles include organo-metallics, phenols, quaternary ammonium salts, and organo-silicones. These finishes should be durable, have selective activity towards undesirable organisms, be compatible with other finishes and dyes, and be nontoxic to man [1]. Chitosan, as a deacetylated derivative of chitin, is a natural, non-toxic and biodegradable polymer. Chitosan is also known as an antimicrobial polysaccharide due to antimicrobial action of the amino group at the C-2 position of the glucosamine residue.(omitted)

• Journal of Microbiology and Biotechnology
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• 제18권1호
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• pp.104-106
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• 2008

Enterobacter sp. BL-2 excretively produced a unique cationic polyglucosamine biopolymer PGB-1 comprised of more than 95% D-glucosamine in an acetate-mediated culture condition. The excretion of the biopolymer PGB-1 was closely associated with the cellular morphology of Enterobacter sp. BL-2, a feature highly dependable on the pH of the medium. The initially formed uneven and irregular surface cells were aggregated into the cell-biopolymer network structure connected by the adhesion modules of the cell-bound biopolymer. The excretive production of the biopolymer PGB-1 coincided with the disruption of the cell-biopolymer network, most actively at the medium pH of 8.0.

• 한국어업기술학회:학술대회논문집
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• 한국어업기술학회 2000년도 춘계수산관련학회 공동학술대회발표요지집
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• pp.416-417
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• 2000

Chitin, a poly $\beta$-(1longrightarrow14)-N-acetyl-D-glucosamine, is best known as a cell wall component of fungi and as a skeletal materials of invertebrates. Chitosan is derived from chitin by deacetylation in the presence of alkali. Chitosan has been developed as new physiological materials since it possesses antibacterial activity, hypocholesterolemic activity and antihypertensive action. However, the actions of chitosan in vivo still remain ambiguous as the physiological functional properties because most animal intestines, especially the human gastrointestinal tract, do not possess enzyme such as chitosanase which directly degrade the $\beta$-glucosidic linkage in chitosan, and consequently the unbroken polymers may be poorly absorbed into the human intestine. Therefore, recent studies as chitosan have attracted interest for chitosan oligosaccharides, because the oligosaccharides process not only water-soluble property but also versatile functional properties such as antitumor activity, immune-enhancing effects, enhancement of protective effects against infection with some pathogens in mice and antimicrobial activity (Kingsnorth et al., 1983, Mori et al., 1997). (omitted)

• 한국섬유공학회:학술대회논문집
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• 한국섬유공학회 2003년도 가을 학술발표회 논문집
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• pp.157-158
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• 2003

키틴은 N-acethyl-D-glucosamine이 $\beta$-(1$\longrightarrow$4) 결합한 천연 고분자이며, 게나 새우 등의 갑각류, 오징어 등의 연체류, 그리고 곤충류 및 균류의 세포벽 등에 광범위하게 분포되어 있다. 키틴은 지구상에 존재하는 천연 다당류 중에 셀룰로오스 다음으로 많은 양이 존재하며 흡착성, 보습성, 유화성 및 생분해성을 가진 무독성 물질이고 항균작용, 생체적합성 등 다양한 특성을 기능을 가진다. 그러나, 분자내에 존재하는 아세트아미노기가 분자간의 수소결합으로 매우 강하게 결합되어 있기 때문에 화학약품에 대한 내성이 강할 뿐만 아니라 물과 대부분의 일반 유기용매에 녹지 않기 때문에 그 용도가 한정되어 있다. (중략)