• 한국식품영양과학회지
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• 제42권6호
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• pp.964-968
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• 2013

쌀품종에 따른 hydrocolloids를 첨가하여 쌀만두피를 제조 시 쌀가루의 입도, 쌀만두피의 조리특성 및 조직감을 측정한 결과, air classifying mill(ACM)을 이용하여 건식분쇄한 쌀가루의 입도 분포는 중력분과 유사하였고, 평균입자크기를 중심으로 조밀한 입자 분포를 나타내었다. 조리특성에서 hydrocolloids를 첨가한 경우, 밀양260호의 무게증가율은 낮아졌으나 한아름은 증가하는 경향을 나타냈다. 만두피의 조리 후 조직감은 쌀 품종별로 차이가 나타남을 관찰할 수 있었으며, hydrocolloids를 첨가함에 따라 경도가 낮고 탄성은 증가함을 알 수 있었다. Hydrocolloids를 첨가한 경우 첨가하지 않은 군에 비해 가공 특성 및 조리 후 특성 모두 우수함을 알 수 있었으며, 쌀 품종 및 첨가물의 종류에 따라 다른 특성을 관찰할 수 있어 쌀 품종별 이화학적 특성과 hydrocolloids와의 관계를 보다 더 많은 연구를 진행해보아야 할 것으로 생각되어진다.

• Journal of Microbiology and Biotechnology
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• 제32권6호
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• pp.749-760
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• 2022

α-Galactosidase is a debranching enzyme widely used in the food, feed, paper, and pharmaceuticals industries and plays an important role in hemicellulose degradation. Here, T26, an aerobic bacterial strain with thermostable α-galactosidase activity, was isolated from laboratory-preserved lignocellulolytic microbial consortium TMC7, and identified as Parageobacillus thermoglucosidasius. The α-galactosidase, called T26GAL and derived from the T26 culture supernatant, exhibited a maximum enzyme activity of 0.4976 IU/ml when cultured at 60℃ and 180 rpm for 2 days. Bioinformatics analysis revealed that the α-galactosidase T26GAL belongs to the GH36 family. Subsequently, the pET-26 vector was used for the heterologous expression of the T26 α-galactosidase gene in Escherichia coli BL21 (DE3). The optimum pH for α-galactosidase T26GAL was determined to be 8.0, while the optimum temperature was 60℃. In addition, T26GAL demonstrated a remarkable thermostability with more than 93% enzyme activity, even at a high temperature of 90℃. Furthermore, Ca²⁺ and Mg²⁺ promoted the activity of T26GAL while Zn²⁺ and Cu²⁺ inhibited it. The substrate specificity studies revealed that T26GAL efficiently degraded raffinose, stachyose, and guar gum, but not locust bean gum. This study thus facilitated the discovery of an effective heat-resistant α-galactosidase with potent industrial application. Meanwhile, as part of our research on lignocellulose degradation by a microbial consortium, the present work provides an important basis for encouraging further investigation into this enzyme complex.

• 한국염색가공학회지
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• 제31권4호
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• pp.233-240
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• 2019

Dyeing is an essential process for improving the value of textile products, but it is considered as one of industries causing pollution because of producing wastewater containing hazardous chemicals as well as using a large amount of water and energy. Global demand for greener technologies in textile field is getting much more attention and accordingly, the use of eco-friendly natural dyes is growing much larger. In textile printing, both dyes and pigments can be used. Pigment printing is more simple process and requires less water and less energy, compared to dye printing. In this study, the organic pigment was prepared from the marigold colorant. Samples were stencil printed, pressed(70℃, 3min) and then heat treated(150℃, 5min). The uptake of polyacrylic acid as a chemical binder was the lowest. In particular, marigold pigments were excellent in color and texture when Guar Gum and Sodium Alginate were used as binders. In addition, the light and washing fastness was rated very high as 4, 4/5 grades, and the rubbing fastness was also excellent as 3 and 4 grades.

• 한국펄프종이공학회:학술대회논문집
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• 한국펄프종이공학회 2006년도 PAN PACIFIC CONFERENCE vol.1
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• pp.1-18
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• 2006

A novel transmission electron microscopy technique for the visualization of polymers adsorbed on secondary fines has been developed. This technique has been utilized in observing the adsorption behavior of various wet-end additives. The technique is sensitive enough not only to allow differentiation between linear and branched polymers, but also to observe differences in the adsorption behavior and conformational characteristics of particular polymeric derivatives. Conformational changes of a cationic polyacrylamide (CPAM) were examined in response to variations in wet-end conditions, such as mixing time and system conductivity. The molecular conformations of cationic starch and cationic guar gum were also examined by this technique. The technique has been employed to observe the effects of silica microparticles on the conformational characteristics of CPAM (drainage/retention aid) pre-adsorbed on secondary fines. The transmission electron microscopy method is a viable tool for investigating the macromolecular events that make up a large part of wet end chemistry in papermaking.

• 한국미생물·생명공학회지
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• 제26권4호
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• pp.316-322
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• 1998

N-$\varepsilon$-aminocaproyl-$\alpha$-D-galactopyranosylamine-sepharose를 담체로 하는 affinity chromatography에 의한 해바라기씨 유래 $\alpha$-galactosidase($\alpha$-D-galactoside galactohydrolase EC 3. 2. 1. 22)의 정제방법과 정제효소에 대한 효소화학적 성질을 규명하였다. N-$\varepsilon$-aminocaproyl-$\alpha$-D-galactopyranosylamine의 흡착제를 합성하여 sepharose에 coupling하였다. 기질 p-nitrophenyl $\alpha$-D-galactopyranoside에 대한 정제효소의 비활성은 291.66 units/mg였고, 조효소와 비교하여 115배의 정제 배율을 나타내었다. 정제효소의 순도는 SDS-polyacryl amide gel전기 영동법 에 의해 단일 band를 나타내었으며, 분자량은 42,000으로 추정되었다. 정제효소의 최적 pH와 온도는 4.5, 55$^{\circ}C$이며, pH 4-5, 30-55$^{\circ}C$의 범위에서 pH와 온도 안정성을 나타내었다. 또한 정제효소는 Ag$^{2+}$, Hg$^{2+}$, CO$^{2+}$의 금속에 의해 70%이상의 저해효과를 나타내었다. 정제효소는 melibiose, raffinose 및 copra galactomannan에 대한 galactose의 유리를 TLC에 의해 확인하였고, 각 기질에 대한 galactose의 가수분해 속도를 HPLC에 의해 비교하였다.

• Journal of Biosystems Engineering
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• 제39권4호
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• pp.345-351
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• 2014

Purpose: Rapid detection of bacteria is very important in agricultural and food industries to prevent many foodborne illnesses. The objective of this study was to develop a portable nuclear magnetic resonance (NMR)-based system to detect foodborne pathogens (E. coli). This study was focused on developing a method to detect low concentrations of magnetic nanoparticles using NMR techniques. Methods: NMR relaxometry was performed to examine the NMR properties of iron nanoparticle mixtures with different concentrations by using a 1 T permanent magnet magnetic resonance imaging system. Exponential curve fitting (ECF) and inverse Laplace transform (ILT) methods were used to estimate the NMR relaxation time constants, $T_1$ and $T_2$, of guar gum solutions with different iron nanoparticle concentrations (0, $10^{-3}$, $10^{-4}$, $10^{-5}$, $10^{-6}$, and $10^{-7}M$). Results: The ECF and ILT methods did not show much difference in these values. Analysis of the NMR relaxation data showed that the ILT method is comparable to the classical ECF method and is more sensitive to the presence of iron nanoparticles. This study also showed that the spin-spin relaxation time constants acquired by a Carr-Purcell-Meiboom-Gill (CPMG) pulse sequence are more useful for determining the concentration of iron nanoparticle solutions comparwith the spin-lattice relaxation time constants acquired by an inversion recovery pulse sequence. Conclusions: We conclude that NMR relaxometry that utilizes CPMG pulse sequence and ILT analysis is more suitable for detecting foodborne pathogens bound to magnetic nanoparticles in agricultural and food products than using inversion recovery pulse sequence and ECF analysis.

• Journal of Microbiology and Biotechnology
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• 제20권11호
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• pp.1546-1554
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• 2010

A bacterial strain capable of producing extracellular ${\alpha}$-galactosidase was isolated from a sample of sugarcane industrial waste. Microbiological, physiological, and biochemical studies revealed that the isolate belonged to Bacillus sp. Furthermore, based on a 16S rDNA sequence analysis, the new isolate was identified as Bacillus megaterium VHM1. The production of ${\alpha}$-galactosidase was optimized based on various physical culture conditions. Guar gum and yeast extract acted as the best carbon and nitrogen sources, respectively. The optimum pH was 7.5 and the enzyme remained stable over a pH range of 5-9. The enzyme was optimally active at $55^{\circ}C$ and thermostable with a half-life of 120 min, yet lost 90% of its residual activity within 120 min at $60^{\circ}C$. One mM concentrations of $Ag^2$, $Cu^2$, and $Hg^{2+}$ strongly inhibited the ${\alpha}$-galactosidase, whereas the metal ions $Fe^2$, $Mn^{2+}$, and $Mg^{2+}$ had no effect on the ${\alpha}$-galactosidase activity, and $Zn^{2+}$, $Ni^{2+}$, and $Ca^{2+}$ reduced the enzyme activity slightly. When treated with the B. megaterium VHM1 enzyme, the flatulence-causing sugars in soymilk were completely hydrolyzed within 1.5 h.

• 한국식품영양과학회지
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• 제27권4호
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• pp.705-711
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• 1998

The digestibility of xylooligosaccharide(XO) by juices of the digestive tract and retardation effect of XO on the adsorption of bile acids were compared with fructooligosaccharide(FO) and isomaltooligosaccharide(IO). In vitro digestion experiments showed that any hydrolyzed products of FO, IO and XO were not detected by HPLC after reaction with saliva, pancreatic, artifical intesteinal, and large intestinal luices, and artifical sera for 4 hours at 37$^{\circ}C$. However, IO were mostly digested by the small intestinal juice, and some quantity of FO were digested. XO were not digested at all by any enzyme of digestive tract. In order to investigate retardation effect of XO on the bile acid absorption. In vitro, permeability of bile acid against dialysis membrane was determined in the mixture which contained guar gum instead of XO was set 100%. The premeability of bile acid showed about 50% in the FO and IO mixture and 43% in the XO mixture. The activity of lactase in FO group and activity of sucrase and maltase in XO group in rat small intestinal mucosa were significantly decreased. Consequently, the present results indicate that XO is indigestible in digestive tract and has retarding effect of adsorption of bile acid compared with the other oligosaccharides. The disaccharidase activity of the XO dietary group was lower than that of the other oligosaccharides dietary group. Furthermore, it was suggested that hydrolysis of sugar may be retarded in digestive tract and glucose level in blood may be controlled effectively by the XO.

• Preventive Nutrition and Food Science
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• 제11권3호
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• pp.226-231
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• 2006

This study evaluated the weight reduction effect of Angook cereal mixture. The cereal mixture was prepared with barley, unpolished rice, corn, soybean, Garcinia cambogia, guar-gum, maltodextrin, glucomannan and a vitamin mixture. Eighteen female college students participated in this 8 weeks weight control program. All subjects were randomly assigned to the treatment and placebo groups. Mean energy intake of the treatment group was $1,356.4{\pm}79.9\;kcal$ (carbohydrate: 67.1%, protein: 18.7%, fat: 14.2%) and placebo group consumed $1,367.6{\pm}71.8\;kcal$ (carbohydrate: 64.2%, protein: 19.7%, fat: 16.1%) during program. The placebo group lost $3.9{\pm}0.8\;kg$ of body weight and the treatment group lost $5.9{\pm}0.7\;kg$ of body weight. There were significant differences in the decrease of total body weight, absolute fat mass, waist circumference (WC) and hip circumference (HC) between the two groups (p<0.05), however, the lean body mass was not significantly decreased in the treatment group compared to the placebo group. There were no differences in the changes in blood glucose, total-cholesterol, HDL-choloesterol, LDL-cholesterol and triglycerides between groups. These findings suggest that the intake of Angook cereal mixture may be beneficial for the reduction of the body weight, absolute fat mass, WC and HC.

• 한국펄프종이공학회:학술대회논문집
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• 한국펄프종이공학회 2001년도 추계학술발표논문집
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• pp.43-43
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• 2001

원료의 저급화와 공정의 폐쇄화가 급속히 진행되고 있는 현재의 국내 제지산업 현황을 고려할 때 고품질의 제품을 저렴하게 생산하기 위해서는 화학첨가제의 효과적 활용기술 확립과 이를 통한 초지공정 wet end의 성공적 제어기술이 요청된다. 특히 환경보전과 환 경관련 규제에 부응하기 위하여 초지공정의 무방류화가 점차 가속화되고 있는 현 시점에 서 wet end의 효율적 관리를 위해서는 그 동안 개방형 wet end에서 적용되던 개념의 공 정관리의 한계를 극복할 수 있는 기술 개발이 필요하다. 공정의 폐쇄화에 따른 습부화학적 문제를 해결하기 위해서는 백수의 재활용에 따른 지료 화학적 특성을 평가하고 고분자전해질의 거동을 분석해야 한다. 보류향상제 혹은 탈수촉 진제로서 첨가된 고분자전해질은 그 기능을 수행하기 위해서는 섬유에 흡착이 이루어져 야 하므로 백수로 제조된 지료 내에서 고분자전해질의 흡착 특성을 파악하는 것은 습부에 서 일어나는 현상들에 대한 이해 및 효율적인 공정제어를 위한 첫 단계라 할 수 있다. 본 연구에서는 실험실적으로 제조된 백수를 이용하여 조성된 지료 내에서 양이온성 구 아 검의 흡착현상을 분석하였다. 본 연구에서는 폐쇄화의 기준으로 폐쇄화 정도(Level of C Closure ; LC)에 따라 실험을 수행하였다. 여기에서 LC란 총 사용된 물의 양에 대한 지료조성 시 사용되는 백수의 양을 백분율로 나타낸 것이다. 양이온성 구아 검의 흡착을 평가하기 위해 PhenoVsulfuric acid spectrophotometric method를 이용하여 펄프 슬 러리 상등액에 존재하는 미흡착된 양이온성 구아 검의 함량을 측정하였고. 양이온성 구아 검 이 섬유상에 흡착하였을 때 나타나는 섬유의 S-potential 변화와 펄프 상등액의 양이 온 요구량 변화를 평가하였으며 이들의 상관관계를 분석하였다.축력으로 변형시키는데 비해 도침은 단순히 압축 압력만을 종이에 가하는 것이 다르다고 볼 수 있는데, 라 이너지와 백상지가 같은 조건하에서 왜 이러한 큰 차이를 보이는 이유를 아직 알수 없다.해 동일한 공정 데이터들올 이용하여 보편적으로 사용하는 통계기법 중의 하나인 주성분회귀분석을 실시하였다. 주성분 분석은 여러 개의 반응변수에 대하여 얻어진 다변량 자료의 다차원적인 변 수들을 축소, 요약하는 차원의 단순화와 더불어 서로 상관되어있는 반응변수들 상호간 의 복잡한 구조를 분석하는 기법이다. 본 발표에서는 공정 자료를 활용하여 인공신경망 과 주성분분석을 통해 공정 트러블의 발생에 영향 하는 인자들을 보다 현실적으로 추 정하고, 그 대책을 모색함으로써 이를 최소화할 수 있는 방안을 소개하고자 한다.금 빛 용사 둥과 같은 표면처리를 할 경우임의 소재 표면에 도금 및 용 사에 용이한 재료를 오버레이용접시킨 후 표면처리를 함으로써 보다 고품질의 표면층을 얻기위한 시도가 이루어지고 있다. 따라서 국내, 외의 오버레이 용접기술의 적용현황 및 대표적인 적용사례, 오버레이 용접기술 및 용접재료의 개발현황 둥을 중심으로 살펴봄으로서 아직 국내에서는 널리 알려지지 않은 본 기 술의 활용을 넓이고자 한다. within minimum time from beginning of the shutdown.및 12.36%, $101{\sim}200$일의 경우 12.78% 및 12.44%, 201일 이상의 경우 13.17% 및 11.30%로 201일 이상의 유기의 경우에만 대조구와 삭제 구간에 유의적인(p<0.05) 차이를 나타내었다.는 담수(淡水)에서 10%o의 해수(海水)로 이주된지 14일(日) 이후에 신장(腎臟)에서 수축된 것으로 나타났다. 30%o의 해수(海水)에 적응(適應)된 틸라피아의 평균 신사구체(腎絲球體)의 면적은 담수