• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2016년도 춘계 학술논문 발표대회
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• pp.83-84
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• 2016

For the slip resistance test of shower room floor, the "O-Y Pull Slip Meter method (O-Y·PSM)" regulated under KS M 3510. This test method uses cooking oil as a substitute of soapy water, and thus it does not reflect the real condition. In this study, on 10 types of floor material samples, the Coefficient of Slip Resistance Bath (CSR·B) on bare foot between 10 types of body wash solution and 6 types of SDS solution was compared. The body wash solution is a mixture of soap and water in 1:20 ratio. As a result, SDS 0.1% solution was the most suitable for a substitute of soapy water in shower.

• 산업기술연구
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• 제18권
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• pp.259-265
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• 1998

The molecular weights of surfactant SDS(M.W. 288) and SLS(M.W. 420) are smaller than the molecular weigh cut-off of cellulose acetate membrane used in this study. However, 20% of SDS and 67% of SLS were rejected by cellulose aectate membrane. The higher rejection rate of SLS than that of SDS is due to the longer hydrophobic chain and greater molecular weight. There was no resistance to permeation rate by membrane fouling. Most of permeation resistance was due to the concentration polarization. Permeation rate was declined with operating time and with increase in concentration of surfactant due to concentration polarization.

• 한국작물학회지
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• 제44권4호
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• pp.373-381
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• 1999

Six soybean cultivars having different SDS susceptibility were planted with sorghum seedinoculum infested with F. solani isolate 171 in the greenhouse. First leaf symptoms appeared on unifoliar leaves at 9 days after inoculation and all cultivars showed the typical leaf symptoms at 13 days after inoculation, when trifoliar leaves emerged. Leaf symptoms development in susceptible cultivars was faster than in resistant cultivars. Leaf symptom severities during the period of 25 to 29 days after inoculation showed a significant difference between cultivars which had SDS resistance and sus ceptibility. In this period, area under the diseaseprogress curve (AUDPC) of Hartz 6686 was the highest and that of PI 520733 was the lowest. SDS caused serious damage to the growth of soybean in all cultivars. Average reductions of growth rate of root fresh weight and dry weight were greater than those of plant tops. Duyu-kong showed less severe leaf symptoms than that of SDS suscetible cultivars; however, average growth rate of plants top and roots of this cultivar was less but not significantly different than those of SDS susceptible cultivars. In all cultivars, as severity of leaf symptoms increased, plant top weight decreased. Root rot symptoms were observed in all cultivars before leaf symptoms appeared. Average proportions of tap root reddish-brown discoloration of all cultivars was up to 75 % at 15 days after inoculati on; however there was no significant differenc between cultivars at each rating date. Appearances of leaf symptoms on leaves varied in each cultivar. SDS resistant cultivars had a significantly higher level of crinkling than susceptible cultivars and SDS susceptible cultivars had a significantly higher level of necrosis than resistant cultivars. Further study will be needed to identify the relationships between the physiological growth rate and SDS severities in soybeans.

• Nutrition Research and Practice
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• 제7권1호
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• pp.3-8
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• 2013

Buckwheat is known as a health food but is one of the major food allergens triggering potentially fatal anaphylaxis in Asia, especially in Japan and Korea. This study was conducted to investigate the characteristic of enzymatic resistance of buckwheat protein and allergenic potential. Enzymatic resistance of buckwheat protein was performed with in vitro digestibility test in simulated gastric fluid (SGF), pH 1.2, using pepsin and simulated intestinal fluid (SIF) using chymotrypsin. Reactivity of buckwheat proteins to human IgE was performed using six allergic patients sensitized to buckwheat. Buckwheat's IgE levels were measured using the Phadia UniCAP-system. Buckwheat protein, 16 kDa, still remained after 30 min treatment of pepsin on SDS-PAGE. Even though 16 kDa almost disappeared after 60 min treatment, two out of the six buckwheat patients' sera showed reactivity to hydrolysate after 60 min treatment, indicating that allergenicity still remained. In simulated intestinal fluid (SIF) using chymotrypsin, buckwheat protein, 24 kDa, showed resistance to hydrolysis with chymotrypsin on SDS-PAGE, and still had allergenicity based on the result of ELISA. Our results suggest that buckwheat proteins have strong resistance to enzyme degradation. This may be attributed in part to the allergenic potential of buckwheat. Further study should be continued regarding buckwheat allergy.

• 한국작물학회지
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• 제44권4호
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• pp.382-390
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• 1999

In order to identify the responses of Korean soybean cultivars to sudden death syndrome (SDS), forty-two Korean cultivars and three check cultivars (Hartwig and PI 520733 are resistant; Hartz 6686 is susceptible) were tested with sorghum seed inoculum infested with Fusarium solani f. sp. glycines isolate 171 in the greenhouse. This isolate has blue pigment cultural shape on potato dextrose agar (PDA) medium. All Korean cultivars inoculated with F. solani isolate 171 showed the typical SDS symptoms and disease severity on soybean leaves in each cultivar varied at 4 weeks after inoculation. Nine cultivars were included in the most SDS susceptible group and six cultivars were included in the most susceptible group based on Duncan＇s multiple range tests (P$\leq$0.05). In results of the LSD analysis for SDS the resistant group, a total of twenty-five Korean cultivars were included in the same SDS resistant group as PI 520733 or Hartwig and fourteen Korean cultivars were included in the same SDS susceptible group as Hartz 6686. In the second experiment, ten Korean cultivars, ten U.S. cultivars, and one introduced line were compared in the same way as the first experiment Disease severity ranking of check cultivars, Hartwig, PI 520733, and Hartz 6686, were the same as in the first experiment. Within Korean cultivars, seven cultivars showed the consistent severity proportions of leaf symptoms. Disease rankings of these cultivars in this experiment were the same as those in the first experiment. Three US cultivars: Hartwig, Hartz 5454, and Forrest, three Korean cultivars： Keunolkong, Myeongjunamulkong, and Jinpumkong 2, and one introduced line, PI 520733, were included in the highest SDS resistant group. Shinphaldalkong 2, Milyang 87, and Samnamkong consistently showed the highest SDS susceptibility in both experiments. Average disease severity in the first and the second experiment were 49.56% and 45.39%, respectively.

• Journal of Microbiology and Biotechnology
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• 제27권4호
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• pp.775-784
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• 2017

A neutral xylanase (CcXyn) was identified from Coprinus cinereus. It has a single GH10 catalytic domain with a basic amino acid-rich extension (PVRRK) at the C-terminus. In this study, the wild-type (CcXyn) and C-terminus-truncated xylanase ($CcXyn-{\Delta}5C$) were heterologously expressed in Pichia pastoris and their characteristics were comparatively analyzed with aims to examine the effect of this extension on the enzyme function. The circular dichorism analysis indicated that both enzymes in general had a similar structure, but $CcXyn-{\Delta}5C$ contained less ${\alpha}-helices$ (42.9%) and more random coil contents (35.5%) than CcXyn (47.0% and 32.8%, respectively). Both enzymes had the same pH (7.0) and temperature ($45^{\circ}C$) optima, and similar substrate specificity on different xylans. They all hydrolyzed beechwood xylan primarily to xylobiose and xylotriose. The amounts of xylobiose and xylotriose accounted for 91.5% and 92.2% (w/w) of total xylooligosaccharides (XOS) generated from beechwood by CcXyn and $CcXyn-{\Delta}5C$, respectively. However, truncation of the C-terminal 5-amino-acids extension significantly improved the thermostability, SDS resistance, and pH stability at pH 6.0-9.0. Furthermore, $CcXyn-{\Delta}5C$ exhibited a much lower $K_m$ value than CcXyn (0.27 mg/ml vs 0.83 mg/ml), and therefore, the catalytic efficiency of $CcXyn-{\Delta}5C$ was 2.4-times higher than that of CcXyn. These properties make $CcXyn-{\Delta}5C$ a good model for the structure-function study of $({\alpha}/{\beta})_8$-barrel-folded enzymes and a promising candidate for various applications, especially in the detergent industry and XOS production.

• 생명과학회지
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• 제12권4호
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• pp.483-489
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• 2002

S. cerevisiae에서 glucoamylase 유전자의 promoter와 signal sequence 그리고 MF$\alpha$1의 prosequence를 이용하여 합성 곤충 defensin를 발현하고 항균활성을 보유한 형태로 분비하는데 성공하였다. Defensin의 여러 생화학적인 특성을 조사한 결과 열 안정성이 높아 10$0^{\circ}C$에서 30분간 가열하여도 항균활성을 온전히 유지하였으며 조사한 pH 영역, 2.0-12.0에서 항균활성의 변화가 없었다. 또한 여러 단백질 분해효소를 처리하면 항균활성이 완전히 사라졌으나 전분질 분해효소, 섬유소분해효소 및 지질분해효소의 처리는 항균 활성에 전혀 영향이 없었다. 황산암모늄침전, SP-Sepharose column cormatography, RP-HPLC 등의 조작을 통해 defensin을 순수한 형태로 정제하였으며 Tricine-SDS-PAGE를 통해 분자량이 약 4.0 kDa임을 확인하였고 정제한 defensin은 항균활성을 보유하였다.

• Korean Chemical Engineering Research
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• 제47권2호
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• pp.190-194
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• 2009

본 연구에서는 공업용수 중에 미량 함유될 수 있는 철 이온을 제거하기 위해 음이온 계면활성제 SDS를 주입하여 미셀을 형성한 후, 미셀과 철 이온이 결합된 응집체를 관형 세라믹 정밀여과막으로 배제하였다. 철 모사용액을 대상으로 SDS 농도가 철과 SDS 제거율에 미치는 영향을 알아본 결과, 철의 제거율은 SDS의 임계미셀농도(CMC)인 8.00 mM에서 가장 높은 92.26%를 나타내었고, SDS 제거율은 칼슘 이온 제거 결과보다 다소 높은 61.10%를 보였다. SDS의 농도가 증가함에 따라 최종 막오염에 의한 저항 $R_f$가 증가하여 4 mM일 때 가장 높은 값을 보이다가 10 mM에서 가장 낮은 값을 나타내었다. SDS 10 mM인 조건에서 최종 투과선속 $J_{180}$가 가장 큰 값을 나타냈었고, 결국 가장 높은 총여과부피를 얻을 수 있었다. CMC 8 mM의 경우 운전시간 80분까지는 10 mM과 동일하게 낮은 $R_f$ 값을 보이다가, 120분까지 급격하게 증가하다가 다시 180분까지 서서히 증가하는 경향을 보였다.

• 한국미생물·생명공학회지
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• 제22권3호
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• pp.240-245
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• 1994

Relation the phage defense mechanism of phage resistant Lactococcus lactis subsp. cremoris ATCC 11602-A1 to its cell wall components was investigated. To determine whether teichoic acid which is known to be one of the phage receptor site present on the cell wall, phage adsorption was examined after treatment 5% TCA(60%$\CIRC $C) and concanavalin A to the cell wall of A1 and parent strain. However, the adsorption rate of two strains did not change. Total amount of phosphate after TCA treatment did not change in both strains, but a difference between the two strains was observed. Ribitol and glycerol, components of teichoic acid, could not be detected in the cell walls of two strains by GC analysis. These results suggest that although teichoic acid was not present in the cell walls of both strains, the composition of cell wall of two strains was not identical. Measurement of amount of protein and SDS-polyacryamide gel electrophoresis were carried out to examine the involvement of cell wall protein in phage resistance, showing that protein is nothing to do with phage adsorption of parent strain, but phage resistance of A1 is related to protein. Cell wall carbohydrates of A1 contained rhamnose, glucose, and galactose. Total amount of carbohydrate of 1% SDS-treated A1 cell wall was reduced to the level of parent strain. The results suggest that phage resistance of A1 was due to the presence of a higher level of carbohydrates then parent strain, and to interaction of carbohydrate and protein.

• 미생물학회지
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• 제40권3호
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• pp.232-236
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• 2004

Streptomyces coelicolor A3(2)의 acetyl xylan esterase (AxeA)가 Escherichia coli의 과산화수소 저항성에 미치는 영향을 알아보고자 하였다. AxeA 발현은 isopropyl-$\beta$-thiogalactoside로 유도되었고 생산된 AxeA는 SDS-polyacrylamide gel electrophoresis방법으로 확인하였다. AxeA 발현에 따른 과산화수소 저항성의 변화를 E. coli의 생장곡선과 생존율을 통하여 조사하였다. AxeA가 발현되지 않으면 모든 처리 농도 (1 mM, 2.5mM, 5mM)에서 균의 사멸이 일어났다. AxeA가 발현되는 조건에서는 5mM을 제외한 과산화수소 1mM와 2.5mM에서 E. coli의 사멸이 저지되었다. 또한 1.5mM의 과산화수소에 대한생존율이 59%에서 74%로 높다졌다. 동시에 E. coli의 최고생장온도에서에 근접한 $45^{\circ}C$에서의 생존율도 증가되는 결과를 얻었다. 그러므로 AxeA 단백질은 산화적 스트레스와 온도스트레스에 대해 교차 저항성을 나타내는 역할을 한다고 결론지었다.