• 펄프종이기술
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• 제38권5호
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• pp.24-30
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• 2006

This study was performed to characterize inverse emulsion type cationic polyacrylamide (PAM) and to compare with powder and salt dispersion type PAMs as a retention and drainage aid. Salt dispersion type PAM has defects of high amount of salt which increases conductivity of white water, low active polymer contents and relatively worse retention and drainage properties than others because of its low molecular weight. Powder type PAM has benefit of high active polymer contents and good retention and drainage properties, but defects of low dissolution speed and insoluble particle generation were observed. However, inverse emulsion type showed the best retention and drainage aids among them by controlling molecular weight and morphology easily and it had relatively higher active polymer contents and better solubility.

• Journal of Microbiology and Biotechnology
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• 제12권1호
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• pp.1-7
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• 2002

The effects of DO and pH on the mass production of pullulan with high molecular weight and the morphology of A. pullulans ATCC 42023 were evaluated. A. pullulans showed a maximum production of pullulan (11.98 g/l) when the initial pH of the culture broth was 6.5 in a shake-flask culture. In a batch culture, the mixture of a yeast-like and mycelial cell forms was found at a pH of 4.5, and the maximum production of pullulan (13.31 g/l) was obtained. However, a high proportion of high molecular weight pullulan (M.W.>2,000,000) was produced at a pH of 6.5, with a yeast-like morphology. The maximum pullulan production yield ($51\%$) was obtained at a pH noncontrol (initial pH 6.5) and DO control (above $50\%$) condition. Pullulan degrading enzyme was activated when the pH of the broth was lower than 5.0 and the portion of low molecular weight pullulan was increased. The formation of a black pigment was observed at an initial stationary phase, at 40 h of fermentation. Therefore, the fermentation should be carried out in a pH noncontrol (initial pH of 6.5) and DO control (above $50\%$) condition, and should be harvested before reaching the stationary phase (around 40 h) for the production of high molecular weight pullulan.

• 한국수산과학회지
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• 제32권4호
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• pp.495-500
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• 1999

[ $\lambda$ ]-carrageenan 고유의 특성을 유지하면서 용해성을 높인 저분자 $\lambda$-carrageenan을 제조하여 보다 효율적으로 식품산업에 이용하기 위하여 초음파를 이용하여 $\lambda$-carrageenan을 저분자화하는 최적조건을 조사한 결과 $\lambda$-carrageenan의 초음파 처리시 각 처리조건들과 저분자화 효과와의 상관관계를 나타내는 반응표면식을 구한 결과, carrageenan 농도와 초음파 강도가 저분자화에 미치는 주 영향인자인 것으로 나타났다. 그리고 저분자화를 위한 초음파 처리의 최적 조건은 초음파 처리온도 $10^{\circ}C$, 초음파 강도 121.64 $W/cm^2$, 시료 carrageenan 농도 $2\%$, 초음파 처리시간 40분이었다. $\lambda$-carrageenan 및 저분자화된 $\lambda$-carrageenan의 분자량을 조사한 결과 대조구 $\lambda$-carrageenan의 분자량은 약 250,000이었으며 초음파처리에 따른 저분자화 된 $\lambda$-carrageenan의 분자량은 각각 p-1의 경우 약 200,000정도였으며, p-2의 경우 약 60,000정도이었다.

• 한국식품과학회지
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• 제40권5호
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• pp.545-550
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• 2008

본 연구는 톳에서 푸코이단의 추출시 초음파 공정을 이용하여 처리함으로써 유래 푸코이단의 저분자화를 통한 면역활성 및 항암활성의 증진 효과를 알아보고자 톳 유래 푸코이단 및 저분자 푸코이단(분자량 14,000 이하)을 이용하여 수행하고, 푸코이단 표준물질과 비교하였다. 시료 첨가를 통한 면역 B세포와 T세포의 생육도에서 톳 유래 저분자 푸코이단이 1.0 mg/mL의 농도에서 무첨가 대조구와 비교해 각각 367%와 387%의 생육도를 나타내며 가장 높은 활성을 나타내었다. 면역세포의 cytokine 분비량 측정에서도 생육도 측정에서와 유사한 결과를 나타내며 저분자 푸코이단이 가장 많은 cytokine 분비량을 나타내었으며, 이는 NK 세포의 생육에도 영향을 끼치는 것으로 사료되는 바, NK 세포 생육 증진에서도 가장 높은 수치를 나타냈다. 인간 정상세포를 이용한 세포독성 측정에서는 시료 간 큰 차이를 보이지는 않았으나 1.0 mg/mL에서 푸코이단 표준물질이 21.45%로 가장 높은 수치를 나타내었고, 저분자된 톳 유래 푸코이단이 19%로 가장 낮은 수치를 나타내었다. 인간폐암세포인 A549와 유방암세포인 MCF-7에 대한 생육억제 활성 측정에서도 저분자 푸코이단이 1.0 mg/mL의 농도에서 각각 69.8%와 83.3%를 나타내었으며, 푸코이단 표준물질도 55% 이상의 활성을 나타내었다. 이상의 결과를 통해 푸코이단 시료는 저분자화를 통해 면역 및 항암활성의 증진이 가능함을 확인하였다.

• Elastomers and Composites
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• 제15권4호
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• pp.241-255
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• 1980

• 한국섬유공학회:학술대회논문집
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• 한국섬유공학회 1995년도 추계 학술발표회
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• pp.119-119
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• 1995

• Bulletin of the Korean Chemical Society
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• 제17권5호
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• pp.480-483
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• 1996

• 대한약학회:학술대회논문집
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• 대한약학회 2005년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2
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• pp.93-95
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• 2005

• 한국식품저장유통학회:학술대회논문집
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• 한국식품저장유통학회 2007년도 학술발표회
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• pp.27-31
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• 2007

This study relates to low and medium molecular weight isoflavone-${\beta}$-D-glucan produced by submerged liquid culture of Agaricus blazei, a method of producing the isoflavone-B-D-glucan using autolysis enzyme of Agaricus blazei mycelia, and use of the isoflavone-B-D-glucan for anti-cancer and immunoenhancing effect. In acordance with one aspect of the present study, it deals with a method of producing isoflavone-${\beta}$-D-glucan, which comprises the followings; 1) culturing and separating mushroom mycelia, 2) producing low-medium molecular weight isoflavone-${\beta}$-D-glucan from high molecular weight one. The cytotoxicity on human cnacer cell line (Caco-2, MCF-7), the expression of Cyclin D, Bcl-2, Bax protein, p21 protein, p53 protein in MCF-7 cells assessed by SDS-PAGE and immunoblotting, and other immuno related factors such as TNF-${\alpha}$ and IL-1B activities were examined. Structural identification of isoflavone-${\beta}$-D-glucan which showed cytotoxicity against cancer cell and immunoenhancing effects was carried by separation with DEAE-cellulose column chromatography, TLC, HPLC, IR, NMR. Clinical test for the cancer patients (n=119) for 6 month was carried out, and immunoenhancing factors (NK. cell number, ratio of T4/T8) were checked. We concluded the identified isoflavone-${\beta}$-D-glucan has immuno enhancing effects and could be useful for cancer chemoprevention.

• Elastomers and Composites
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• 제51권3호
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• pp.188-194
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• 2016

In this study, novel quaternary plastomers consisting of ethylene, 1-hexene, high ${\alpha}$-olefin, and divinylbenzene were prepared using Zr metallocene catalyst, borate type cocatalyst, and tri-isobutylaluminium. The molar ratio changes of 1-hexene and high ${\alpha}$-olefin (1-octene, 1-decene, and 1-dodecene) had an effect on the properties of the quaternary plastomers. The structure of the quaternary plastomers was characterized using $^1H$ NMR. Molecular weight properties, crystallinity, and thermal properties of the plastomers were determined by GPC, WAXS, and DMA, respectively. Compared with the terpolymers prepared in our previous study, molecular weight and molecular weight distribution of the quaternary polymers were very similar, whereas glass transition temperature ($T_g$) was very low. Also, hardness and tensile properties of the quaternary plastomers were measured.