• Microbiology and Biotechnology Letters
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• v.18 no.1
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• pp.56-60
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• 1990

A bacterial strain of Brevibacterium sp. CHI was isolated from soil and used to produce an enzyme (nitrile hydratase) necessary for carrying out the bioconversion of acrylonitrile to acrylamide. Various immobilization methods and enzyme stability were investigated. The nitrile hydratase showed the maximum stability at pH 7 for the free cells. EDTA and phenyl methyl sulfonyl fluoride were selected as the protease inhibitor and the enzyme stability was evaluated by changing inhibitor concentration. Acrylamide beads were the best carriers among four carriers we tested in terms of stability and physicoehemical strength. The storage stability of the immobilized cells decreased with increasing acrylamide concentration of the gel phase at 4$^{\circ}C$, and was very low at acrylarnide concentration above 25%.

• Analytical Science and Technology
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• v.11 no.2
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• pp.139-144
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• 1998

For the ambient monitoring of acrylamide, the adequate condition of sampling and analysis was checked. The adequate adsorbents and desorption solvents were tested. The combination of charcoal tube as a adsorbent and acetone as a desorption solvent showed 87% desorption efficiency. Flame ionization detector was used to detect acrylamide. The detection limit was 0.814 mg acrylamide in 1 L acetone. It is the equivalent concentration of 0.0203 mg acrylamide in $1m^3$ air if the volume of air collected was 40L. The permissible exposure level (PEL) of acrylamide in the workplace air recommended by Occupational Safety and Health Administration (OSHA, USA) is 0.3 mg acrylamide in $1m^3$ air. So, it is very simple and economic analytical method for acrylamide to be set in the industrial hygiene laboratories.

• The Journal of Natural Sciences
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• v.9 no.1
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• pp.31-37
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• 1997

Apoptosis is an important event in the anticancer drug therapy. p53 was demonstrated to serve a key component to lead tumor cell death by inducing apoptosis. However, recent study showed the presence of p53 independent apoptotic pathway (Gaftenhaus et al., 1996). We were curious to know it apoptosis induced by adriamycin, a genotoxic anticancer agent, involved p53 gene mutation. Thus this study investigated the p53 gene mutation status among HeLa cell population during apoptosis induced by adriamycin. Under our experimental condition, 12 hour treatment of 1 ${\mu}m$ adriamycin caused apoptosis which was monitored by DNA fragmentation assay. In order to see the p53 gene mutation status, exons of 5, 7 and 8 of p53 gene, where previously reported p53 mutation hot spots reside, were amplified by PCR and nucleotide sequence change was scanned. However, no nucleotide change was observed among apoptotic HeLa cell population. Therefore this study demonstrated that adriamycin induced apoptosis without causing p53 gene damage.

• Journal of the Korean Wood Science and Technology
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• v.32 no.2
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• pp.50-57
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• 2004

This study attempted to evaluate the water repellency and drying effectiveness of linseed oil treated-solid wood at high temperature by immersion. The moisture content of green wood (Pinus densiflora) sample (above 90%) was reduced about 10% after 6 hours treatment at 150℃. When the treated samples were cut into cross section along the length, it was observed that the linseed oil penetrated into up to 20% of the sample cross section area in all locations. However, a strength loss of the specimen was not detected. The pre-drilling before linseed oil treatment was effective in reducing the defects such as checks and splits, and improved the linseed oil penetration into all samples from the surfaces. The result of water absorption test of treated-wood showed that the water repellent efficacy of treated-wood was greater than that of the control. The anti-fungal activity of treated samples using five sap stains and thee decay fungi was not detected in broad-spectrum toxic mechanism. However, decay test using white rot fungi (Tyromyces palustris) and brown rot fungi (Trametes versicolor) showed that the treated sample has a decay resistance to these two fungi.

• Journal of Life Science
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• v.16 no.2 s.75
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• pp.323-327
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• 2006

The Formation of acrylamide was studied in Maillard model reaction systems based on asparagine-glucose. The mixture of asparagine and glucose in equal molar ratio, and then heated at 125, 150, 175 and $200^{\circ}C$ for 10, 20 and 30 minute, respectively. The reaction products were extracted with ethyl acetate and methanol, and then isolated and detected on FFAP capillary column and HP-5MS 5% phenyl methyl siloxane column by using GC/MS. Acrylamide was detected only from methanol extracts and on FFAP capillary column, at retention time 23.53 min., and the detection limit was 4.6 ng. Acrylamide content mainly increased with increasing temperature and processing time till $175^{\circ}C$, therefore, maximal acrylamide formation occurred at $175^{\circ}C$ for 10 minute ($116{\mu}g/g$), while, above $175^{\circ}C$, higher temperatures or prolonged processing times caused a decrease of acrylamide levels, finally disappeared at $200^{\circ}C$ for 30 minute. Three major compounds were identified as 1,3-dihydroxypropanone, 2,3-dihydro-3,5-dihydroxy-6-methyl-4H-pyrane-4-one and 5-hydroxymethylfurfural, and three minor compounds also as 5-methylfurfural, 2-acetylpyrrole and N,N-dimethylcyclohexamine, from ethyl acetate or methanol extracts on FFAP or HP-5MS capillary column.

• Horticultural Science & Technology
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• v.30 no.5
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• pp.603-612
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• 2012

In order to select potato clones for making cold chip, this study analyzed the glucose content, acrylamide content, and the correlation between the two properties after harvest, $4^{\circ}C$ and $8^{\circ}C$ low-temperature storage, and $20^{\circ}C$ heating treatment of 47 breeding clones and control cultivars 'Atlantic', 'Sumi', and 'Gui Valley'. In all of the control cultivars and 47 clones, glucose content was below 0.25% and acrylamide content was below 1000 ppb just after harvest, but after $4^{\circ}C$ low-temperature storage both the glucose content and acrylamide content increased rapidly and only 4 clones H7, H13, H16, and H40 showed a level below 500 ppb. In $8^{\circ}C$ low-temperature storage as well both contents increased, but the increase was relatively smaller than that in $4^{\circ}C$ low-temperature storage. In addition, $20^{\circ}C$ heating treatment decreased both contents. In the results of analyzing the correlation between glucose content and acrylamide content at low-temperature storage, a positive correlation was observed. In conclusion, clones H7, H13, H16, and H40 showing low glucose content even at low-temperature treatment were found to contain less acrylamide and therefore they were selected as potato clones suitable for making cold chip.

• Clean Technology
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• v.17 no.4
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• pp.314-324
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• 2011

Several amide derivatives have been used as additives for base oil of metal working fluids and pressure working oils. In this paper, a series of succinic acid alkyl half-amide derivatives were synthesized as over 97% yields by ring-opening reaction of succinic anhydride and several amines and were soluble in 100 N base oil within 1 wt% concentration. The structures of the synthesized amides were confirmed by $^1H$-NMR, FT-IR spectrum and GC analysis. Anti-corrosion properties of the amides in sea water were evaluated through ASTM D665 method and weight loss method. As the results of anti-corrosion properties, the properties of the amides with shorter alkyl chain and high concentration showed better performance than those with longer alkyl chain and low concentration. Also, the dialkyl amides showed better anti-corrosion properties than those of the monoalkyl amides. Inhibition efficiency% (IE%) was over 93% in the concentration of 40 ppm and corrosion rate (CR) was below 0.5 mm/year in the same concentration.

• Proceedings of the Korean Fiber Society Conference
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• 2003.04a
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• pp.413-414
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• 2003

폴리아마이드 섬유, 즉 나일론 섬유에 응용될 수 있는 여러 종류의 이온성 염료들 중에서 섬유분자와 염료의 결합특성에 기인하는 산성염료의 사용이 현재 주를 이루고 있지만 결합력에서 기인하는 염료의 탈착으로 말미암아 색상강도의 저하 및 첨부포에의 오염이 문제가 되고 있다. 또한 함금속 염료를 이용한 방법에서는 세탁 및 일광에 대한 견뢰도 향상은 얻을 수 있지만, 원하는 수준의 견뢰도를 얻기 위해서는 후처리의 적용도 고려되어진다. 반응성 염료$^{1.2)}$ 를 이용한 염색은 셀룰로오스 섬유에의 적용이 대부분이며, 양모 및 견에 대한 응용도 발표되고 있다. (중략)

• The Safety technology
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• no.143
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• pp.14-15
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• 2009

안전을 담당하는 관리자로서 때로는 근로자분들에게 싫은 소리를 해야 하고 때로는 언성을 높이며 다투기도 해야 했던 때가 있었습니다. 같은 직장 안에서 다른 동료나 근로자와 원활한 관계를 유지하고 싶지 않은 사람은 아마 한 명도 없을 것입니다. 하지만 안전관리자라는 직업을 택한 이상 안전하지 않은 행동이나 상태를 보고 '좋은 게 좋은 거라' 넘길 수는 없는 노릇일 것입니다. 안전사고로 생명을 잃거나 영원히 불구로 힘든 나날을 살아가는 동료를 옆에서 지켜봐야 했던 경험이 아마 지금의 제가 조금이라도 더 열심히 제 일에 최선을 다하도록 하는 원동력이 되고 있지 않을까 합니다. 앞으로도 제가 선택한 이 일에 보람과 사명감을 갖고 끝까지 최선을 다하도록 하겠습니다.

• Journal of the Korean Chemical Society
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• v.49 no.6
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• pp.609-612
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• 2005