• Korean Journal of Food Science and Technology
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• v.30 no.6
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• pp.1476-1479
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• 1998

Effect of chitosan oligosaccharides on the ACE (angiotensin I converting enzyme) inhibition and antihypertension in SHR (Spontaneously hypertensive rat) was examined. The ACE inhibition activity was observed in all the chitosan oligosaccharides used in this study, and chitosan trimer exhibited the highest inhibitory activity $(IC_{50}=0.9{\mu}M)$ compared with other chitosan oligosaccharides $(IC_{50}\;:\;2.4{\sim}100\;{\mu}M)$. The results suggested that chitosan trimer was a good inhibitor of ACE in molecular level. When the single oral dose (2.14 mg/kg, similar to dose level of Captopril, known as strong ACE inhibitor) of chitosan trimer was given to 8 or 21 week aged SHR, the blood pressure reduction of both SHRs in 4hrs were $27{\pm}4.8\;mmHg\;and\;36{\pm}4.3\;mmHg$, respectively. Therefore, it was suggested that chitosan trimer could be applicable as natural ACE inhibitor related to antihypertension.

• The Korean Journal of Food And Nutrition
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• v.16 no.4
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• pp.437-443
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• 2003

Chitooligosaccharides were prepared by enzymatic hydrolyzing of crab shell chitosan. Low molecular weight chitooligosaccharides(LMW-chitooligosaccharides), 64.3% of which was composed of trimer, tetramer, and pentamer, was obtained by hydrolyzing chitosan with the chitosanase originated Bacillus pumilus BN-262. High molecular weight chitooligosaccharides(HMW-chitooligosaccharides), 49.3% of which was composed of chitooligosaccharides over heptamer, was obtained by hydrolyzing chitosan with the cellulase originated Trichoderma viride. Acute oral toxicity of chitooligosaccharides were tested in mice. Chitooligosaccharides did not have any toxic effect in mice and oral LD$\_$50/ value of chitooligosaccharides was over 5.0g/kg in mice.

• Journal of Veterinary Clinics
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• v.18 no.3
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• pp.257-264
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• 2001

This study was performed to investigate the effects of chitosan-trimer (CT) on the prevention of postoperative adhesion formation in the rate model. All animals divided into PBS (control), 1% CT, 3% CT, and chitin treated group. The mean adhesion score in 1% CT group (1.03$\pm$0.63), 3% CT group (0.64$\pm$0.53) and chitin group (1.67$\pm$0.71) was found to be lower than that in control group (2.07$\pm$0.81). More favorable adhesion prevention was achieved in 3% CT group (0.64$\pm$0.53) in comparison with the control group, 1% CT group, and chitin group without any hemorrhagic complications. A statistically significant difference was observed in adhesion formation between control group and 3% CT group (p<0.001). In control group, 44 of 45 sites (97.7%) formed adhesions between the intestine defects. In contrast, 3% CT was effective in reducing the incidence of adhesion formation to 17 to 45 sites (62.2%) (p<0.05). The locations of adhesions were observed in serosa-serosa (60%), serosa-mesentery (13.3%), serosa-connective tissue of testis (10%), omentum-liver (10%), serosa-omentum (3.3%), serosa-cecum (3.3%), and serosa-incision (0%). On the results of histological analysis, grade of inflammation and fibrosis at the sites of postoperative peritoneal adhesion formation were not significantly different in all groups. But, 3% CT showed the lowest score of inflammation and fibrosis. In 3% CT group, the rate of increase of plasma fibrinogen was significantly lower compared with that in control group from pre-operation to 10 days later (p<0.05). There were no appreciable difference in the CBC, leukocyte differential counts and total protein concentrations among four groups. In conclusion, our data suggested that CT should be effective on reducing adhesion formation in experimental rat models. The results also showed that 3% CT does not adversely affect normal wound healing and healthy recovery after operation.

• The Korean Journal of Food And Nutrition
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• v.14 no.6
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• pp.579-584
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• 2001

Chitooligosaccharides were prepared by enzymatic hydrolyzing of crab shell chitosan. Low Molecular Meight chitooligosaccharides(LMW-chitooligosaccharides) , 64.3% of which was composed of trimer, tetramer, and pentamer, was obtained by hydrolyzing chitosan with the chitosanase originated Bacillus pumilus BN -262. High Molecular Meight chitooligosaccharides ( HMW-chitooligosaccharides ) , 49.3% of which was composed of chitooligosaccharides over heptamer, was obtained by hydrolyzing chitosan with the cellulase originated Trichoderma viride. Antimicrobial activity and colony forming inhibitory activity of chitooligosaccharides were tested. MIC of LMW-chitooligosaccharides against Bacillus cereus, Bacillus subtilis, Candida albicans, Escherichia coli, Escherichia coli O157 : H7, Lactobacillus plantarum, Listeria monocytogenes, Pseudomonas aeruginosa, Salmonella enteritidis, Salmonella typhimurium, Staphylococcus aureus and Streptococcus mutans was 1.5%, 1.5% above 2.0%, 1.5%, 1.5%, below 0.5%, 2.0%, 1.5%, above 2.0%, 1.0%, 1.5% and 1.0% respectively. .

• Korean Journal of Fisheries and Aquatic Sciences
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• v.35 no.6
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• pp.696-701
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• 2002

Optimal conditions for preparing of chitooligosaccharides from chitosan with cellulase was researched by response surface methodo-logy, Penicillium funiculosum derived cellulase was most effective for chitooligosaccharides production as the point of hydrolyzing activity and commercial utility. The result which measures the change of degrading ratio at time course, 10 hr reaction showed a exponential increase and after that time degrading ratio was not changed. The optimal conditions determined by response surface methodology with central composite design of total 26 species were $0.5\%$ of chitosan, 143 U enzyme, 49$^{\circ}C$ of reaction temperature, 13.2 hr of reaction time and pH 3.8. Major chitooligosaccharides produced from chitiosan on optimal conditions were dimer and trimer.