• Polymer(Korea)
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• v.39 no.3
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• pp.480-486
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• 2015

The adhesion of tissue and organ occur with frequency after surgery. Theomosensitive hydrogel was prepared from poloxamer/chitosan/epidermal growth factor as adhesion barrier agent. The prepared hydrogel showed sol-gel transition temperatures around human temperature and gelation temperature was the faster within 1 min. The hydrogel sustained the release of epidermal grow factor during 7 days. The hydrogel was highly effective for the prevention of tissue and organ adhesion in rat model. The thermosensitive and antibacterial chitosan hydrogel can be useful to consider the anti-adhesion barrier with increased adhesion of organ and sustained release of epidermal growth factor.

• Korean Journal of Agricultural Science
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• v.31 no.2
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• pp.77-86
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• 2004

This study was aimed to determine the effect of high molecular weight chitosan treatment on the decay incidence and fruit quality in strawberries. Preharvest spray of chitosan (0.2%) effectively reduced the incidence of grey mould and increased fruit firmness. Chitosan application was also effective on remaining of surface gloss. This is probably due to coating effect. Physiological disorders were not found in treatment of 4 sprays. Internal quality such as soluble solid content and acidity seemed not to be affected by chitosan application. The effect of chitosan on keeping freshness was clear in fruit without physical damage at harvest, but much less effective in injured fruit. Postharvest application of chitosan did not affect fruit quality. Above results indicated that chitosan is an alternative to keep strawberry quality through delaying decay and keeping firmness.

• The Journal of the Korea institute of electronic communication sciences
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• v.9 no.3
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• pp.323-328
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• 2014

Effect of chitosan with sirloin specimens from chitosan-fed and normal-fed pig. The specimens were observed by a optical microscope and their biophoton was measured by a photomultiplier(PMT)tube. Results of experiments showed that specimens of the chitosan-fed pig had lower biophoton rate than that of the normal-fed pig. As a result of the organization were also shown pictures Chitosan as a pork loin tissue and fat in the flesh less delicate and compactness is found that tastes good. Thus by PMT fleshy tissue biochemical measurements to measure the change of state to be one of the new method is to be expected.

• The Korean Journal of Food And Nutrition
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• v.22 no.2
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• pp.308-312
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• 2009

In this study, the effects of low molecular weight chitooligosaccharides were assessed. Low molecular weight chitooligosaccharide evidenced no cytotoxicity in in vitro trials with the normal cell line, Vero E6(Africa green monkey kidney cell). The $IC_{50}$ of low molecular weight chitooligosaccharide was $923.20{\mu}g/m{\ell}$. Low molecular weight chitooligosaccharide exhibited in vitro antineoplastic activity in five human tumor(lung carcinoma, bladder carcinoma, colon carcinoma, stomach carcinoma, breast carcinoma) cell lines. The $IC_{50}$ values of low molecular weight chitooligosaccharide on A549, J82, SNU-C4, SNU-1 and ZR75-1 were $477.42{\mu}g/m{\ell}$, $480.40{\mu}g/m{\ell}$, $436.84{\mu}g/m{\ell}$, $373.55{\mu}g/m{\ell}$, and $539.95{\mu}g/m{\ell}$, respectively.

• The Korean Journal of Food And Nutrition
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• v.22 no.4
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• pp.639-643
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• 2009

In this study, the antineoplastic effects of chitosan hydrolysates were assessed. The chitosan hydrolysates showed no cytotoxicity in in vitro trials using the normal cell line, Vero E6(Africa green monkey kidney cells). The $IC_{50}$ value of the chitosan hydrolysates on Vero E6 was 1,107.95 ${\mu}g/m{\ell}$. The hydrolysates exhibited in vitro antineoplastic activity in five human tumor (lung carcinoma, bladder carcinoma, colon carcinoma, stomach carcinoma, breast carcinoma) cell lines. The $IC_{50}$ values of the hydrolysates on A549, J82, SNU-C4, SNU-1, and ZR75-1 cells were 421.06, 417.99, 445.54, 380.65 and 460.49 ${\mu}g/m{\ell}$, respectively.

• Journal of the Korean Society of Clothing and Textiles
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• v.33 no.12
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• pp.1965-1970
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• 2009

This study examined the effect of surfactant pretreatment on the pectinase-treated cotton/chitosan blends by weight loss and properties such as water absorbency, dyeability, tensile strength, pilling property, and surface morphology. The weight loss of cotton/chitosan blends was 1.5% by the surfactant pretreatment/pectinase treatment. The water absorbency and dyeability of samples showed a significant improvement by the surfactant pretreatment/pectinase treatment. The tensile strength and pilling property of treated fabrics showed no change. The water absorbency and dyeability of pectinase treated samples improved with the pretreatment of the surfactant without damaging the fibers.

• Korean Journal of Food Science and Technology
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• v.32 no.4
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• pp.828-833
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• 2000

The effect of treatments with alcohol, chitosan, or with both alcohol and chitosan for extending the shelf-life of Korean white rice cake and wet noodle was investigated by measuring quality changes such as total microbial count, pH, and sensory qualities. Total microbial counts for control, alcohol-treated, and 1% lactic acid-treated white rice cakes exceeded the initial putrefactive criterion level of $1{\times}10^{6}\;CFU/g$ at 6, 27 and 20 days of storage, respectively. However, total microbial count of the white rice cake treated with chitosan was still less than the criterion level even at 76 days of storage. In the case of wet noodle, total microbial counts of control and alcohol-treated groups exceeded the criterion level within 7 days of storage, while that of chitosan-treated group was far less than the criterion level even at the end of storage of 82 days. Chitosan treatment extended the shelf-lives of both white rice cake and wet noodle appreciably.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.32 no.3
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• pp.247-251
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• 1999

In spite of various bio-functionalities of chitosan, the effects in vivo were still ambiguous because of its low absorption on organism. Therefore, chitosan oligosaccharides (COSs) are necessary to elucidate for an efficient utilization in vivo. COSs were prepared from chitosan using ultrafiltration membrane enzymatic reactor system with MWCO (molecular weight cut-off) 3,000 Da of membrane. Calcium absorption accelerating effect using COSs was examined by two methods, in vitro and in vivo. In vitro experiment, calcium absorption by the addition of COSs in a mixture solution of calcium and phosphate was higher approximately $50\%$ than that by control. In vivo using rats, group taken the diet contained $1\%$ COSs anil calcium chloride decreased about $75\%$ of calcium content excreted from feces, and then, showed about $15\%$ increase in breaking force of femur. These results demonstrated that COSs definitely involved in calcium metabolism in vivo.

• Applied Chemistry for Engineering
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• v.7 no.1
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• pp.59-66
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• 1996

Novel chitosan beads containing a series of bisamino-terminated polyethylene glycol (Bisamino-PEG, $Jeffamine^{(R)}ED$ series) have been prepared via capillary extrusion method using an alkaline solution. The results of swelling kinetics of chitosan beads showed that as the chain length of PEG in chitosan beads increased, the swelling process of the beads proceeded slowly. In order to study the releasing kinetics quantitatively, fluorescamine was coupled to the pendant amino groups and the releasing processes were followed by UV spectra. The results revealed that the releasing process was retarded in the order of $Jeffamine^{(R)}ED$-600 < $Jeffamine^{(R)}ED$-900 < $Jeffamine^{(R)}ED$-2001 as the chain length of PEG was increased. The slow release of PEG from the beads is considered to be governed by the chain length of PEG and interpolymeric hydrogen bonding between PEG and the chitosan molecule.

• Journal of Life Science
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• v.18 no.11
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• pp.1617-1624
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• 2008

Chitin and chitosan, which is deacetylated form of chitin, are one of the most abundant biomass on the earth. They showed various biological activities including antimicrobial activity, heavy metal chelating, immune system activation, and have very diverse applications in food, pharmaceutical, medicinal, and environmental industry. There have been reported many chitin/chitosan-hydrolyzing enzymes, their structures and genes from three domains, archaea, bacteria, and eukarya. Carbohydrate hydrolyzing enzymes are classified in CAZy (Carbohydrate Active Enzymes) database according to their amino acid sequence similarity. Interestingly, chitinases and chitosanases are classified in various glycosyl hydrolase(GH) families, GH2, GH5, GH7, GH8, GH18, GH19, GH20, GH46, GH48, GH73, GH75, GH80, GH84, and GH85. Here, we review characteristics and structures of chitin/chitosan hydrolyzing enzymes according to glycosyl hydrolase families in order to provide information about gene mining.