• 치위생과학회지
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• 제11권4호
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• pp.375-380
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• 2011

This study evaluated whether fluoride treatment can affect recovery of the irregularity of enamel surface after tooth whitening with a high concentration of hydrogen peroxide (HP) activated by plasma arc light. A total of 36 bovine teeth stained with coke were used in this experiment. The specimens were classified into following three groups (two different commercial plasma arc groups and a control group without light curing source): (1) 35% HP gel only, (2): 35% HP gel and Plasma arc A, and (3) 35% HP gel and Plasma arc B. To measure color changes and surface morphologies before and after the bleaching, colorimeter and scanning electron microscopy were used, respectively. When the specimens were bleached with hydrogen peroxide and plasma arc lights, the bleaching effect was greater than when only hydrogen peroxide gels were used (Kruskal-Wallis test, p<0.05). In addition, plasma arc B showed the more color changes than plasma arc A (Bonferroni post-hoc test, p<0.05). The surfaces of the teeth treated with fluoride gel after the whitening treatment came to be smooth. Therefore, the results of this study suggested that the fluoride application for patients who got tooth whitening therapy with a high concentration of hydrogen peroxide gels activated by plasma arc light will be effective to recover rough enamel surfaces.

• 한국동물학회지
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• 제39권3호
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• pp.248-256
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• 1996

본 연구의 목적은 인간의 Poly(ADP-ribose) synthetase (PARS)의 cDNA를 클로닝하여 발현시키기 위해 수행하였다. 먼저, 인간의 PARS cDNA 전체를 포함한 pPARS3.1을 pGEM-7Zf(+) 등의 발현 벡터 클로닝하였다. 이 결과로 생성된 재조합 플라스미드 pPARS6.1이 인간의 PARS cDNA 전체를 포함하고, 올바른 방향으로 삽입되었는지를 확인하기 위해 제한효소 지도를 작성하였고, random primed DNA probe을 이용한 Southern blot 분석에 의해서 PARS가 클로닝되었다는 것을 확인하였다. 또한, 염기서열 분석 결과, 단백질 합성이 시작되는 유전 암호가 정확한 순서로 위치하고 있음을 확인하였다. 재조합된 pPARS6.1의 발현을 위해 배양시 0.4 mM IPTG로 처리하여 만들어진 인간의 PARS 단백질이 10% SDS-PAGE에서 120 kDa 위치에 이동하였다는 것을 nick-translated된 DNA를 probe로 이용하여 확인하였고, Southwestern blot 실험 결과 120 kDa과 98kDa에 위치하는 단백질이 DNA와 결합함을 알 수 있었다.

• Journal of Pharmaceutical Investigation
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• 제33권1호
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• pp.21-28
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• 2003

Ketorolac tromethamine(KT) is a nonsteroidal agent with potent analgesic and moderate anti-inflammatory activity. The lipid-water partition coefficient of KT was evaluated and KT gel was formulated as a gel containing different pH, different concentrations of polymer (poloxamer 407, carbopol 941), propylene glycol, ethanol and various enhancers. The resulting KT gels were evaluated with respect to their viscosity, in vitro drug permeation rate through hairless mouse skin and stability. In n-octanol and chloroform, the lipid-water partition coefficient of KT was the highest at pH 4 phosphate buffer. The apparent viscosity of KT gel increased with an increase in gel pH, polymer and enhancer concentration. But the apparent viscosity of KT gel decreased with an increase in ethanol concentration. The permeation rate of KT through hairless mouse skin from gels different pH was maximum at pH 4 which is close to KT $pK_{a}$ 3.54. The permeation rate decreased with an increase in polymer, propylene glycol concentration. But the permeation rate increased with an increase in ethanol. The increase of drug concentration from 1 to 3% induced linear increase in permeation rate. The best enhancer was the combination of $Labrasol^{\circledR},\;Transcutol^{\circledR}$, oleic acid and l-menthol. In the accelerated stability test(25, 40 and $50{\circ}C$), pH 5 gel was most stable and pH 4 gel was most unstable for 90 days.

• Preventive Nutrition and Food Science
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• 제15권1호
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• pp.57-66
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• 2010

Passion fruit fiber pectin gels represent a new alternative pectin source with potential for food and non-food applications on a commercial scale. Pectic polysaccharides were extracted from passion fruit (Passiflora edulis) fiber using citric acid as a clean catalyst and autoclaved for 20 to 60 min at $121^{\circ}C$. The best condition of pectin yield with the highest molecular weight was obtained with 1.0% of citric acid (250 mg/g dry passion fruit fiber pectin) for 20 min of autoclaving. Spectroscopic analyses by Fourier transform infrared, enzymatic degradation reactions, and ion-exchange chromatography assays showed that passion fruit pectin extracted for 20 min was homogeneous high methoxylated pectin (70%). Gel permeation analysis confirmed that the pectin extract obtained by autoclaving by 20 min showed higher molecular weights than those autoclaved for 40 and 60 min. Passion fruit pectin extracted for 20 min was enzymatically modified with fungal pectinmethylesterase to create restructured gels. Short autoclave treatment (20 min) with citric acid as extractant resulted in a significant increase of gel strength, improving pectin extraction in terms of functionality. The treatment of solubilized material (pectic polysaccharides) in the presence of insoluble material (cellulose and hemicellulose) with pectinmethylesterase and calcium led to the creation of a stiffer passion fruit fiber pectin gel, while syneresis was not observed.

• 한국작물학회지
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• 제39권2호
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• pp.121-127
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• 1994

(1-3)-$\beta$-glucanase 동위효소의 발현 양상을 등 전점 전기영동 젤에서 직접 검출 확인할 수 있는 방법을 개발하였다. 개발된 방법은 시판되고 있는 (1-3)-$\beta$-glucanase활성 측정용 염료착색 기질을 이용하였다. 본 방법은 신속, 간편하며 보리 종자에서 발현되는 것으로 알려져 있는 모든 (1-3)-$\beta$glucanase 동위효소를 검출할 수 있을 정도로 민감하고 특이적이었다. 시판되고 있는 Penicillium(1-3)-$\beta$-glucanase에 대한 활성 검출 한계단위는 50 $\mu$U 정도로 추정되었다. 따라서, 본 방법은 특별한 시설이나 연구 인력을 확보하고 있지 않는 연구실에서 식물체의 (1-3)-$\beta$-glucanase발현에 대한 단백질 수준에서의 연구를 수행하는데 유용하게 이용될 수 있을 것으로 생각된다.

• 한국식품과학회지
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• 제10권2호
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• pp.157-161
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• 1978

통일 및 팔달쌀 전분의 이화학적 성질을 살펴본 바, 전분의 물결합능력, blue value 및 아밀로스 함량에 서로 차이가 없었다. 팔달 전분은 통일 전분에 비해 팽화력이 높았다. 아밀로그라프에 의한 두전분의 차이는 볼 수 없었으나 통일이 팔달보다 $50^{\circ}C$로 냉각시 점도가 다소 높았다. 또한 통일 아밀로스의 intrinsic viscosity는 팔달 아밀로스보다 높았으나 아밀로펙틴은 두 전분모두 비슷한 값을 보였다. 전분 gel의 retrogradation 속도는 $21^{\circ}C$에서 통일이 팔달보다 다소 빨랐다.

• Applied Biological Chemistry
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• 제39권1호
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• pp.49-53
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• 1996

산처리 전분은 0.2N HCl을 사용하여 $45^{\circ}C$에서 20분, 40분, 60분간 반응시켜 얻었다. 산처리에 의해 전분의 팽윤력과 용해도가 증가하였으며 이러한 변화는 낮은 온도에서부터 나타났다. Sepharose 2B-CL을 사용한 전분의 겔 크로마토그래피 결과 산처리 시간이 길어질수록 아밀로펙틴 부분이 약간 감소하는 반면 아밀로오스에 해당하는 부분이 약간 증가하는 경향을 보였으나, 산처리에 의한 차이는 크게 나타나지 않았다. 온도 변화에 따른 가용성 탄수화물의 용출 양상은 가열 온도가 증가함에 따라 분자량이 큰 분자들의 용출이 증가되었고, 산처리 시간이 길어질수록 가용성 탄수화물의 총 용출량이 증가하였다. 여러 온도에서 가열하여 만든 전분 겔의 텍스쳐 실험 결과 시료겔의 견고성은 $85^{\circ}C$로 가열한 겔에서 가장 크게 나타났으며, 산치리에 의해 겔의 견고성이 증가하였다. 전분의 응집성은 무처리 전분의 경우 온도가 증가함에 따라 계속 증가하는 경향을 보였으나, 산처리 전분은 $85^{\circ}C$로 가열한 겔에서 가장 큰 값을 나타내었고 그 이후에는 응집성이 감소하였다.

• 한국수산과학회지
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• 제48권5호
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• pp.589-595
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• 2015

Alginates are used to encapsulate various materials, including food, cosmetics, and pharmaceuticals. This study examined the properties and oxidation stability of fish oil capsules manufactured with calcium alginate gels. The fish oil capsules were manufactured by dropping sodium alginate solution and fish oil into a calcium chloride solution through nozzles. The membrane thickness, sphericity, rupture strength and deformation depth of the fish oil capsules were determined. The peroxide value of the fish oil was assayed to determine the oxidation stability of the capsules. The capsules measured approximately 3 mm with a membrane thickness of 90 μm independent of the amount of fish oil added. As the amount of fish oil encapsulated increased, the sphericity, rupture strength and deformation depth of the capsules decreased. The encapsulation efficiency increased until the amount of fish oil was 30%. The oxidation stability of fish oil in capsules was dependent on the type of nozzle, e.g., the oxidation stability of fish oil in capsules made using a double nozzle was greater than with a single nozzle. These results should lead to industrial application of fish oils including eicosapentaenoic (EPA) and docosahexaenoic (DHA) acids, as nutraceuticals.

• 한국세라믹학회지
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• 제30권7호
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• pp.535-542
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• 1993

It was investigated in this study that a preparation method, activation energy, surface area, pore volume, pore size distribution and DTA analysis of the dry gel in process of producing monolithic porous gel in Li2O-Al2O3-TiO2-SiO2 system by the sol-gel technique using metal alkoxides. Activation energy for gellation according to the variation of water concentration and the kind of catalysts ranged from 10 to 20kcal/mole. Monolithic dry gels were prepared after drying at 9$0^{\circ}C$ when the amount of water for gellation was 4~8 times more than the stoichiometric amount, that was necessary for the full hydrolysis of the mixed metal alkoxide. The specific surface area, the pore volume, the average pore radius of the dried gel at 18$0^{\circ}C$ according to the various kinds of catalyst were about 348~734$m^2$/g, 0.35~0.70ml/g and 10~35$\AA$, respectively. It showed that the dry gels were porous body. As a result ofthe analysis of DTA, it was confirmed that the exothermaic peaks at 715$^{\circ}C$ and 77$0^{\circ}C$ was clue to the crystallization of dried gel.

• 한국식품영양과학회지
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• 제40권7호
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• pp.1048-1052
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• 2011

각기 다른 치환도를 가진 초산 고구마전분 페이스트의 유동특성 및 투과도 그리고, 이들 전분 겔의 냉.해동안정성 및 강도가 치환도의 함수로 분석되었다. 유동특성 측정 결과 power law 모델식과 Casson 모델식에 잘 적용되었으며, 높은 shear-thinning 거동을 가지고 있는 것으로 나타났다. 특정한 온도 범위($25{\sim}70^{\circ}C$)에서 전분 페이스트의 겉보기 점도($\eta_{a,100}$)의 온도 의존성은 Arrhenius 모델식에 잘 적용되었으며 초산 고구마전분이 천연전분에 비해 더 낮은 온도 의존성을 나타내었다. 전분 페이스트 이수현상 측정에서는 초산화에 의해 이수현상이 감소하는 것으로 나타났으며, 치환도가 증가할수록 낮아지는 것으로 나타났다. 겔 강도 측정에서도 초산화에 의해 겔 강도가 감소하는 것으로 나타났으며, 치환도가 증가할수록 겔 강도는 감소하는 것으로 나타났다. 페이스트 투과도(% T) 측정에서 초산전분은 천연전분 보다 투과도가 높은 것으로 나타났다.