• Journal of Life Science
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• v.9 no.1
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• pp.17-21
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• 1999

Chitosan derivitives, a sulfated N-acetylchitosan was synthesized, and artificial skin of sulfated N-acetylchitosan and N-carboxyl butyl chitosan were investigated. Sulfated derivatives of chitosan were analyzed by {TEX}${13}^C${/TEX}-NMR and the structure on N-acetyl chitosan 3,6-O-disulfate were confirmed. Rabbits underwent a midline laparotomy followed either by a bilateral peritoneal sidewall abraison(3.0×1.5cm). The injured surface was then covered with 0.2mm thick sulfated N-acetyl chitosan membrane. Sulfated N-acetyl chitosan membrane was found to reduce postsurgical bleeding after abraison of peritoneal surface treated with sulfated N-acetyl chitosan membrane. Sulfated N-acetyl chitosan implanted rabbit showed quick wound healing than N-carboxybutyl chitosan. With a sterilization procedure of chemical sterilization, sulfated N-acetyl chitosan seem to be better substitutes than N-carboxybutyl chitosan.

• Journal of environmental and Sanitary engineering
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• v.21 no.1 s.59
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• pp.21-34
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• 2006

To investigate anti-HIV-1 activity of water soluble chitosans, sulfated chitosan derivatives were prepared in mild condition. Various sulfated chitosan derivatives (N-3,6-O-S-chitosan, N-desulfated 3,6-O-S-chitosan, 3,6-O-S-chitin, and 3,6-O-sulfated-N-(o-carboxybenzoyl) chitosan) were synthesized with sulfurtrioxidepyridene complex in pyridine solvent. Characterization of the sulfated chitosan derivatives was carried out by $^{13}C$ NMR and IR spectroscopies. To observe ionic reaction properties, pKas of the sulfated chitosan derivatives and chitosan of low molecular weight were estimated by potentiometric titration. The sulfated chitosan derivatives had high water solubility, pKas (pKa : 7.7) of N-3,6-O-S-chitosan and N-desulfated 3,6-O-S-chitosan were increased than pKa of water insoluble chitosan (pKa : 6.2), These results suggest the participation of electrostatic interaction of amino and sulfate groups on the sulfated chitosans. Anti-HIV-1 drugs, such as AZT, ddC, and ddI for anti-HIV activity had higher selective index compared with SCB-chitosan but N-3,6-O-S-chitosan has shown higher selective index compared with ddC and ddI as HIV drugs.. These results suggest that sulfated chitosan derivatives were expected as an anti-HIV drug with differential driving force mechanism against some nucleoside analogs drug in the future.

• KSBB Journal
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• v.10 no.5
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• pp.525-532
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• 1995

Chitosan derivative, of a sulfated N-acetyl chitosan was synthesized, and the inhibitory effects of this compound on the experimental and spontaneous lung metastallc B16/BL6 melanoma bearing mice were investigated. Position of substitution with sulfate in water-soluble sulfated derivatives of chitosan were analysed by 13C-nmr. The structure of N-acetyl chitosan 3,6 0-disulfate were confirmed. The tumor growth inhibition of B16/BL6 melanoma cells has been shown at the highest level of 77.6% when sulfated N-acetyl chitosan were administered at the dose of 100mg/kg. In the lung metastasls, the sulfated N-atetyl chitosan was administered to C57BL/6B mice bearing B16/BL6 melanoma cells by I.V. injection and the number of metastasis foci of melanoma were decreased by the dose dependent manner ranging from 20 to 100mg/kg. In the spontaneous metastasis, I.V. administrations of sulfated N-acetyl chitosan after tumor inoculation resulted in marked reduction of metastatic colonies. A sulfated N-acetyl chitosan was able to partially inhibit the tumor cell adhesion by migration to laminin. These results suggested that chitosan derivative, a sulfated N-acetyl chitoasn was able to inhibit to the experimental and spontaneous metastasis models as well as cell adhesion ability.

• Polymer(Korea)
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• v.27 no.6
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• pp.583-588
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• 2003

Sulfated chitosan and sulfated sodium alginate were synthesized by sulfating reaction of low molecular chitosan and low molecular sodium alginate with SO$_3$-pyridine complex. When the weight ratio of SO$_3$-pyridine complex to polysaccharide was 1:5, the degrees of sulfation were the highest at 2.75 and 2.53 respectively. The anticoagulation effect was the highest when the molecular weight was 8.0${\times}$10$^3$ Da, and the anticoagulation activity was the highest at 91% of that of heparin when sulfated chitosan and sulfated sodium alginate were mixed at a weight ratio of 1:1. The anticoagulation activity was highest at 84% of that of heparin in the active plastin trombo test (aPTT) when sulfated chitosan and sulfated sodium alginate were mixed at a weight ratio of 1:1.

• Journal of Life Science
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• v.7 no.2
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• pp.149-159
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• 1997

Chitin, a linked polysaccharide composed of 2-acetamido-2-deoxy-$\beta$-D-glucopytanose residues, is distributed widely in nature. It has been utilized on various application field due to the development of chitin derivatives such as chitosan, partial deacetylated chitin, carboxylmethyl chitin, sulfated chitin, and so on. Chitin and chitosan have been recently interested in antitumor and antimicrobial activities, because of a powerful tumor inhibitory effect against experimental mouse tumors. Especially, the oligosaccharides obtained by partial degradation of them exhibited a remarkable antitumor effect against sarcoma 180, MM 48 and Meth Asolid tumors and antimetastatic effect against Lewis lung carcinoma in mice. This review describes on antitumor effects of chitin, chitosan and their oligosaccharides by their mechanism of action involving enhancement of immunological system.

• Membrane and Water Treatment
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• v.1 no.4
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• pp.231-251
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• 2010

The sulfatation of chitosan, by reaction with chlorosulfonic acid under controlled conditions, allowed increasing the pH range of chitosan solubility. The biopolymer was characterized using FTIR and $^{13}C$-NMR spectroscopy, elemental analysis and titration analysis and it was tested for mercury recovery by polymer enhanced ultrafiltration (PEUF). In slightly alkaline conditions (i.e., pH 8) mercury recovery was possible and at saturation of the polymer the molar ratio $-NH_2$/Hg(II) tended to 2.6. Polymer recycling was possible changing the pH to 2 and the polymer was reused for 3 cycles maintaining high metal recovery. The presence of chloride ions influences metal speciation and affinity for the polymer and "playing" with metal speciation allowed using the PEUF process for mercury separation from cadmium; at pH 11 the formation of hydroxo-complexes of Hg(II) limits it retention. Cake formation reveals the predominant controlling step for permeation flux.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.31 no.3
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• pp.447-451
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• 1998

Functional properties such as anti-blood coagulation, angiotensin converting enzyme (ACE) inhibitory activity, fat binding capacity, foaming properties, emulsifying properties and chemical components of sulfated polysaccharides isolated from ascidian tunics were investigated. The sulfated polysaccharide mainly consisted of sulfate, uronic acid, protein, and chondroitin sulfate, among which chondroitin sulfate showed higher concentration while sulfate and uronic acid did lower. Compositional menosaccharides were arabinose, xylose, glucose, galactose, glucuronic acid, N-acetylgalactosamine and N-acetyglucosamine. Especially, galactose content was dominant among them. And emulsifiability and foaminess of the sulfated polysaccharide was higher than the control group. Anti-blood coagulation of sulfated polysaccharide showed with respect to APTT (Activated partial thromboplastin time). ACE inhibitory activity showed about $16.7\%$.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.35 no.6
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• pp.671-675
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• 2002

The present study was conducted to elucidate functional properties of sulfated polysaccharides from ascidian tunics, In physical properties of the crude polysaccharides, emulsion ability and foaminess were more excellent compared with chitin and chitosan, particular dye binding capacity was prominent. Anti-blood coagulation of partially purified sulfnted polysaccharides showed with respect to APTT (Activated partial thromboplastin time). Especially, active fraction $(F_4)$ obtained by DEAE-cellulose ion exchange chromatography showed highest activity, which was approximately $20\%$ of the activity of heparin. ACE inhibitory activity also similar to anticoagulant activity. Active fraction $(F_4)$ obtained by DEAE-cellulose ion exchange chromatography showed about $34\%$, in ACE inhibitory activity.