• 유기물자원화
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• 제21권4호
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• pp.82-87
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• 2013

게껍질에 흡착된 은 이온의 탈착과 재생특성에 관한 연구가 최적의 탈착제로서 선정된 질산을 이용하여 수행되어졌다. 1.0M의 질산농도에서 은 이온의 탈착율은 96%로서 가장 높았다. 또한, 투입된 흡착제의 양과 탈착제의 부피로서 정의되는 S/L비가 1.0보다 작을 때에는 대부분의 은 이온이 탈착되어졌으며 대부분의 탈착 공정은 60분 내에 일어났다. 그리고 재사용된 게껍질을 흡착제로 다시 이용하였을 때 2회까지는 92%의 은 이온 탈착율을 유지하였다.

• 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.

• Animal Systematics, Evolution and Diversity
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• 제36권4호
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• pp.391-395
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• 2020

This study reports the pagurid hermit crab Porcellanopagurus japonicus in Korean waters for the first time. This species has a right cheliped larger than the left one, reduced and globular abdomen, and symmetrical uropods. Porcellanopagurus japonicus is similar to P. nihonkaiensis, a previously reported congeneric species in Korea, but also has distinguished morphological and ecological characters. There are currently issues with the Korean scientific name for P. japonicus, we suggest a reasonable Korean scientific name of this organism with its etymology. In addition, this species inhabits bivalve shells, which is not a typical habitat for hermit crabs, and the unique habitats of this and several other Korean hermit crabs are reviewed.

• 한국응용과학기술학회지
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• 제10권2호
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• pp.41-47
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• 1993

Chitin was isolated from crab shells by modified Hackman's method, which was treated again with aqueous sodium hydroxide solution to give alkali chitin(sodium alkoxide of chitin). And after, the alkali chitin is allowed to react with monochloroacetic acid to synthesize 6-O-(carboxymethyl) chitin [CM-Chitin] under diminished pressure. In order to synthesize high performance CM-Chitin as hygroscopic agent, it was measured that the yield and degree of subsititution of each CM-Chitin according to molar ratio(monochloroacetic acid equivalent mol/N-acetyl-D-glucosamine residue) and their moisture-absorption and moisture-release properties were measured and compared with those of hyaluronic acid. The moisture-absorption and moisture-release properties of CM-Chitin, especially 0.8 in degree of substitution, were found quite similar to those of hyaluronic acid. The preliminary results show that CM-Chitin might be used as hygroscopic agent instead of hyaluronic acid in field of cosmetics.

• 한국세라믹학회지
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• 제55권6호
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• pp.570-575
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• 2018

Hydroxyapatites (HAps) were synthesized using the powdered waste of fishery products, i.e., fish scales and crab shells, as starting materials. HAp was synthesized by a wet-chemistry method followed by calcination at 600 and $800^{\circ}C$. Calcined crabshell powder revealed a single HAp phase and fine powder, while calcined fish-scale powder showed a ${\beta}-TCP$ secondary phase, even at the higher calcination temperature. Dense HAp pellets were obtained from the crab-shell powder by spark plasma sintering at $1000^{\circ}C$ for 10 min under applied pressures of 40 and 80 MPa in a vacuum state, giving sample densities of 2.93 and $3.06g/cm^3$, respectively. The estimated grain size of HAp was $448{\pm}96$ and $283{\pm}59nm$ for applied pressures of 40 and 80 MPa, respectively. In contrast, the HAp obtained using the pressureless sintering technique showed excessive grain growth without further densification.

• 대한약학회:학술대회논문집
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• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.1
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• pp.222.2-223
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• 2003

Renal dipeptidase (RDPase, EC 3.4.13.19), an ectoenzyme of renal proximal tubules, is covalently bound to outer leaflet of lipid bilayer via glycosylphosphatidylinositol (GPI)-anchor. Chitin is a major component of the shells of crustacea such as crab, shrimp and crawfish. This study was conducted to examine the effect of chitosan on RDPase release from renal proximal tubules. Nitric oxide (NO), highly reactive free radical, inhibits the release of RDPase from porcine proximal tubules. (omitted)

• 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.319.2-319.2
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• 2002

Chitin is a major component of the shells of crustacea such as crab. shrimp and crawfish. Renal dipeptidase (RDPase. EC 3.4.13.19), an ectoenzyme of renal proximal tubules. is covalently bound to outer leaflet of lipid bilayer via glycosylphosphatidylinositol (GPI)-anchor. The biological role of RDPase was suggested as the hydrolysis of dipeptide into free-amino acids before renal reabsorption. The underlying biochemical mechanism of decreased RDPase release was suggested as nitric oxide (NO) production. (omitted)

• Biotechnology and Bioprocess Engineering:BBE
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• 제10권1호
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• pp.67-72
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• 2005

To achieve demineralization of crab shell waste by chemical and biological treatments, lactic acid and lactic acid bacterium were applied. In 5.0 and $10\%$ lactic acid, pH rapidly decreased from 6.8 to 4.2 and from 4.5 to 2.4 at day 3, respectively, and thereafter the pH remained at an almost constant level. In a $10\%$ lactic acid bacterium inoculum, pH lowered to 4.6 at day 5. Relative residual ash content rapidly decreased to 49.1 and $16.4\%$ in 5 and $10\%$ lactic acid treatments, respectively, for the initial 12 h. In 2.5, 5 and $10\%$ lactic acid bacterium inoculums, relative residual ash content rapidly decreased to 55.2, 40.9 and $44.7\%$, respectively, on the first day. Residual dry masses were 76.4, 67.8 and $46.6\%$ in 2.5, 5 and $10\%$ lactic acid treatments, respectively, for the initial 12 h. After a one-time exchange of the lactic acid solution, in the $5.0\%$ lactic acid treatment, residual dry mass rapidly decreased from 66.0 to $41.4\%$. In 2.5, 5 and $10\%$ lactic acid bacterium inoculums, residual dry masses decreased to 67.6, 57.4 and $59.6\%$ respectively, on the first day. Protein contents after demineralization ranged from $51.3{\sim}54.7\%$ in the chemical treatments and decreased to $32.3\%$ in the lactic acid fermentation process. A negative relationship was shown between pH and demineralization rate in lactic acid and lactic acid bacterium treatments. These results suggest that lactic acid fermentation can be an alternative for demineralization of crab shells, even though the rate and efficiency of the demineralization is lower than the chemical treatment.

• 유기물자원화
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• 제7권2호
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• pp.83-92
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• 1999

수산물 가공 공장에서 배출되는 게 껍질 폐기물로부터 Chitin을 추출하고 탈아세틸화하여 Chitosan(Cs)을 제조하였다. 이 Cs를 초산 용액중에서 용해한 후 Itaconic acid를 첨가하고 Ceric ammonium nitrate(CAN)를 반응 개시제로 사용하여 Graft-copolymerization 하였다. 본 연구에서는 Cs에 첨가하는 Itaconic acid와 CAN의 농도, 반응온도, 반응시간의 영향에 따른 최적 중합 조건을 도출하고 이 Grafted-copolymer-의 폐수중의 CODcr 유발물과 구리 이온의 제거 능력을 연구하였다. 여기서 CODcr과 구리이온의 제거능력시험에 사용한 폐수는 도광 공장 폐수를 사용하였고, Graft-copolymerization으로 합성된 이 중합체의 동정에는 적외선 스펙트로메타를 사용하였다. 이상의 실험 결과 Graft율은 Cs에 Monomer로써 Itaconic acid를 0.25M농도로 첨가하였을 때, CAN은 $3.5{\times}10^3M$, 반응 온도는 $40^{\circ}C$ 그리고 반응시간은 4시간일때 가장 높았다. 또한, Cs과 Itaconic acid grafted chitosan(CsIa), Cationic polymer를 사용하여 폐수중 유기물과 금속이온의 제거 실험을 한 결과 상등액의 CODcr과 구리 이온 제거율은 Cs와 Cationic polymer 보다CsIa가 보다 효과적이었다. 이것은 합성한 CsIa가 양쪽성 고분자이기 때문이다.

• Archives of Plastic Surgery
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• 제37권4호
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• pp.485-488
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• 2010

Purpose: Paragonimiasis is infectious disease occurred by Paragonimus Westermani, which invades into human body as a final host. Habitual eating the freshwater crab or crawfish unboiled is one of the reason of infection. Paragonimiasis raged in 1970s in Korea, Japan, China and other Asian countries but the incidence decreased rapidly. Once people eat infected second host, parasite penetrates the duodenal wall and migrates to the lung. During this migration period, the parasite can migrate to other organ, such as brain, spinal cord, liver and subcutaneous tissue, but the cases are rarely reported. The objective of our study is to present our experience of the ectopic migration of parasite to the subcutaneous tissue of the abdomen, which was easily treated with excision and Praziquantel medication. Methods: A 59-year-old woman who likes eating unboiled freshwater crab was diagnosed as Paragonimiasis 15 months ago. Her symptoms were fever and cough, and she was treated with Praziquantel medication. 3 months after discharge, she visited our hospital with left pleuritic chest pain, cough with fever, and palpable mass formation on left lower quadrant of the abdomen. Wedge resection of the left lung and Praziquantel medication was maintained for a week. Nevertheless, fever persisted after the treatment. The patient received total excision of the abdominal soft tissue mass, and the fever was relieved. Results: Pathologic findings of the mass showed multiple cyst and abscess formation with crystal structure which is suspicious parts of the parasite or calcified egg shells. Uncontrolled fever was relieved after the operation, and there was no evidence of recurrent Paragonimiasis and ectopic migration for 1 year follow up period. Conclusion: Ectopic migration of Paragonimus is rare, but multiple organ can be involved. Patient with Paragominiasis who was refractory in fever control after Praziquantel medication or surgical evaluation of the lung should be considered as ectopic migration of the Paragonimiasis.