• Parasites, Hosts and Diseases
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• 제50권4호
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• pp.361-364
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• 2012

The mature cyst of Acanthamoeba is highly resistant to various antibiotics and therapeutic agents. Cyst wall of Acanthamoeba are composed of cellulose, acid-resistant proteins, lipids, and unidentified materials. Because cellulose is one of the primary components of the inner cyst wall, cellulose synthesis is essential to the process of cyst formation in Acanthamoeba. In this study, we hypothesized the key and short-step process in synthesis of cellulose from glycogen in encysting Acanthamoeba castellanii, and confirmed it by comparing the expression pattern of enzymes involving glycogenolysis and cellulose synthesis. The genes of 3 enzymes, glycogen phosphorylase, UDP-glucose pyrophosphorylase, and cellulose synthase, which are involved in the cellulose synthesis, were expressed high at the 1st and 2nd day of encystation. However, the phosphoglucomutase that facilitates the interconversion of glucose 1-phosphate and glucose 6-phosphate expressed low during encystation. This report identified the short-cut pathway of cellulose synthesis required for construction of the cyst wall during the encystation process in Acanthamoeba. This study provides important information to understand cyst wall formation in encysting Acanthamoeba.

• 한국염색가공학회지
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• 제5권3호
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• pp.221-228
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• 1993

Cellulose acetate and methyl cellulose were synthesized from waste cellulose in order to make waste knit on value added highly. Crystal waste cellulose by oxidation using $HIO_4$ and then acetylation was decrystallized. A degee of crystallinity was measured by X-ray diffraction and the structure was identified by FT-IR spetroscopy, respectively. Cellulose acetate was prepared from the reaction of decrystallized cellulose with acetic acid, cone-$H_{2}SO_{4}$ and acetic anhydride. Also, structure identification by FT-IR and a degree of crystallinity by X-ray diffraction were performed. DS of the synthesized cellulose acetate was 2.8 and viscosity average molecular weight was 238,000. Also, methyl cellulose was synthesized by treating cellulose acetate with NaOH and iodomethane. DS of the synthesized methyl cellulose was 3.0. Glucose unit with three hydroxy groups was all substituted by methoxyl groups. It was identified by FT-IR spectroscopy. Also, the thermal properties of the synthesized methyl cellulose were examined by DSC. It shewed two shewed melting peaks at 22$0^{\circ}C$ and 24$0^{\circ}C$ in the 2nd scan. It proved that DS=3.0 of methyl cellulose was a thermotropic liquid crystal.

• 한국포장학회지
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• 제16권1호
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• pp.19-25
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• 2010

It is becoming increasingly important to utilize alternative raw materials for plastic industries other than petrochemical-based plastics. Cellulose derivatives were the bases of the original synthetic plastics. Cellulose and its derivatives, especially the widely used cellulose acetate (CA), constitute one of the main classes of raw materials for production on artificial fibers, films, plastics etc. CA is one of the well known polymers produced from naturally available plant substance. Many researches have focused on the isolation of cellulose from the plant cells to use them as cellulose derivatives and composite materials. Chemical and mechanical treatments provide changes on the molecular structures influencing the fundamental properties of these naturally abundant polymer. The aim of this review article is to review biodegradation, synthesis, formation, and utilization of cellulose esters, especially di-acetate, used in packaging related researches.

• Journal of Plant Biology
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• 제29권4호
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• pp.263-284
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• 1986

Effects of putrescine, spermidine and spermine on the activity of D-glucose-6-phosphate cyclohydrolase in the Daucus carota L. protoplast cultured for 4 days and effects of polyamines on the incorporation of D-[u-14C]-glucose treated to protoplasts in culture-medium were investigated. The activity of D-glucose-6-phosphate cyclohydrolase was increased by polyamines and among them spermine was the most effective. Polyamiens increased protein synthesis and this due to the increasing effect of the polyamines on the synthesis of glycoprotein which is one of cell wall components. The synthesis of cell polysaccharides, such sa pectic substances, hemicelluloses and cellulose was increased by polyamines, which stimulated synthesis of pectin substances, and hemicellulose more greatly than that of cellulose, and spermidine was the most effective. In the light of the above results it seems that the polyamines increase cell wall regeneration by the stimulation of enzyme activities which synthesize cell wall components.

• 분석과학
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• 제10권4호
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• pp.291-299
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• 1997

톱밥의 주성분인 cellulose를 이용하여 cellulose-OH를 cellulose-Cl로 전환시킨 다음 킬레이트 시약인 2,2'-iminodibenzoic acid염을 반응시켜 킬레이트 흡착제인 2,2'-iminodibenzoic acid-cellulose를 합성하였다. 그리고 합성된 흡착제를 이용하여 Pb(II)와 Cu(II)의 흡착성을 연구하였다. 흡착 특성에 대한 실험 결과, pH가 증가할수록 금속 이온의 흡착량이 증가함을 알 수 있었다. 최적 흡착 반응시간은 약 1시간, 흡착능과 회수량은 Cu(II)보다 Pb(II)의 경우가 더 좋음을 알 수 있었다.

• 한국펄프종이공학회:학술대회논문집
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• 한국펄프종이공학회 2011년도 추계학술발표회 논문집
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• pp.133-141
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• 2011

• 한국진공학회:학술대회논문집
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• 한국진공학회 2014년도 제46회 동계 정기학술대회 초록집
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• pp.315.1-315.1
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• 2014

The use of cellulose papers has recently attracted much attention in various device applications owing to their natural advantageous properties of earth's abundance, bio-friendly, large-scale production, and flexibility. Conventional metal oxides with novel structures of nanorods, nanospindles, nanowires and nanobelts are being developed for emerging electronic and chemical sensing applications. In this work, both ZnO (n-type) nanorod arrays (NRAs) and CuO (p-type) nanospindles (NSs) were synthesized on cellulose papers and the p-n junction property was investigated using the electrode of indium tin oxide coated polyethylene terephthalate film. To synthesize ZnO and CuO nanostructures on cellulose paper, a simple and facile hydrothermal method was utilized. First, the CuO NSs were synthesized on cellulose paper by a simple soaking process, yielding the well adhered CuO NSs on cellulose paper. After that, the ZnO NRAs were grown on CuO NSs/cellulose paper via a facile hydrothermal route. The as-grown ZnO/CuO NSs on cellulose paper exhibited good crystalline and optical properties. The fabricated p-n junction device showed the I-V characteristics with a rectifying behaviour.

• Journal of Microbiology and Biotechnology
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• 제9권6호
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• pp.704-708
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• 1999

In addition to catalyzing the synthesis of glucan from sucrose as a primary reaction, glucansucrase also catalyzes the transfer of glucose from sucrose to other carbohydrates that are present or are added to the reaction digest. Using dextransucrase and altemansucrase, prepared from Leuconostoc mesenteroides B-742CBM and B-1355C, respectively, we modified the bacterial cellulose in Acetobacter xylinum ATCC10821 culture, and then produced a characteristic cellulose that is soluble and has a new structure. There were also some partially modified insoluble cellulose and oligosaccharides in the modification culture. After methylation and following acid hydrolysis of both the soluble and insoluble glucans, there were ($1{\rightarrow}4$) as well as ($1{\rightarrow}6$) and ($1{\rightarrow}3$) glycosidic linkages in the soluble glucan.

• 원예과학기술지
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• 제28권6호
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• pp.1039-1050
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• 2010

당근은 서양뿐만 아니라 중국 및 한국과 같은 아시아 전역에서 요리로 많이 이용되는 유용한 작물 중 하나이다. 그러나 당근 종자 표면에는 모(毛)가 존재하고 이 종모는 발아율을 증가시키기 위해 제거해야 한다. 더욱이 종모 처리는 시간과 인력 및 자본의 소비와 같은 추가적인 손실을 동반하였다. 이러한 문제점을 방지하기 위해 단모종자를 이용하여 모형성과 관련된 유전자의 연구가 필요하다. 당근 종모의 발달은 2차 세포벽의 합성단계 동안 cellulose의 합성 과정과 연관되어 있음을 바탕으로, EST profiling을 통해 종모와 관련된 유전자를 탐색하고자 하였다. 당근 종모 형성에 관련된 유전자 발현을 조사하기 위해, 성숙 초기 단계의 단모종자 659-1개체와 유모종자 677-14개체를 이용하여 cDNA library를 구축하였다. 단모종자 659-1개체와 유모종자 677-14개체에서 확보된 EST 염기서열의 NCBI database BLASTX 분석을 통한 EST profiling 결과, 172개와 224개의 unigene은 이미 알려진 단백질 염기서열과 상동성을 보였으며 나머지 233개와 192개의 unigene은 확인되지 않는 유전자들이었다. EST는 추정되는 기능에 따라 16개의 category로 그룹화되었다. 전체 EST 중 29개의 unigene이 2차 세포벽 합성 단계 동안 cellulose의 합성 pathway상의 종모 형성을 조절하는 유전자로 추정되며, 실제로 종모 발달과 관련된 14개의 unigene이 유모종자 계통에서만 발견되었다.

• 한국정밀공학회지
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• 제31권8호
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• pp.737-742
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• 2014

This paper reports a customized silver ink and its inkjet printing process on a cellulose electro-active paper (EAPap). To synthesize a silver ink, silver nanoparticle is synthesized from silver nitrate, polyvinylpyrrolidone and ethylene glycol, followed by adding a viscosifier, hydroxyethyl-cellulose solution, and a surfactant, diethylene glycol. The silver ink is used in an inkjet printer (Fujifilm Dimatix DMP-2800 series) to print silver electrodes on cellulose EAPap. After printing, the electrodes are heat treated at $200^{\circ}C$. The sintered electrodes show that the thickness of the electrodes linearly increases as the number of printing layers increases. The electrical resistivity of the printed electrodes is $23.5{\mu}{\Omega}-cm$. This customized ink can be used in inkjet printer to print complex electrode patterns on cellulose EAPap to fabricate flexible smart actuators, flexible electronics and sensors.