• 펄프종이기술
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• 제45권3호
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• pp.59-68
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• 2013

The cotton contains various impurities such as protein, wax, pectins, coloring matter, even though cotton has been a major source of pure cellulose. The purification processes have been commonly applied to obtain the pure cellulose. However the excessive purification treatments could lead to the damage in the cellulose structure which could result in the degradation of cellulose and the limited application of cotton cellulose. In this study, the changes in cellulose structural properties such as crystallinity and DP(degree of polymerization) by the various conditions of the purification processes were investigated. The less toxic agents such as hydrogen peroxide and sodium silicate were applied for the purification treatment in this study. The increase in the process times, the temperature and the applied amount of chemical agents resulted in the more purified cellulose. The DP of cotton cellulose was increased at the first weak conditions by the reduction of small molecules such as pectin, wax, and so on. Especially the 2 % addition amount of $H_2O_2$ with $Na_2SiO_3$ resulted in the higher value in the DP and the brightness compared to the 1.5 % addition amount of $H_2O_2$. However, the 4 % addition amount of $H_2O_2$ with $Na_2SiO_3$ showed the decreased value because of excessive treatment. In case of the changes in the crystallinity (Gjk), the highest value of the crystallinity was obtained by the 2% addition amount of $H_2O_2$ on the cotton cellulose, which showed similar with the change in the DP.

• 생명과학회지
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• 제23권6호
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• pp.838-846
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• 2013

플라즈마는 물질의 제4의 상태로서 이온화된 가스로 불리며 다양한 활성종 및 수산화기, 하전입자, 이온, 자유 전자, 산소등을 발생시키는 특징을 가지고 있다. 20세기 후반에 플라즈마는 산업현장에서 활발히 사용되고 있으며, 최근 저온 상압 플라즈마 장치가 개발되면서 의생명 분야에 적용되기 시작했다. 저온 상압 플라즈마는 인체조직에 열 손상을 입히지 않을 뿐만 아니라, 암 치료, 살균, 치아미백, 지혈, 상처치유 등에서 높은 효율성을 보이고 있다. 이때 발생되는 활성종은 포유세포나 병원균에 영향을 미치는 것으로 알려져 있다. 또한, 다학제간의 연구를 통해 저온 상압 플라즈마의 활용범위는 다양한 영역으로 넓어지고 있으며, 새로운 첨단 의료기술로서의 가치가 높아지고 있다. 저온 상압 플라즈마가 포유세포와 미생물에 적용된 이후, 지난 10여 년간 급속한 발전을 통해 최근 플라즈마 메디신이란 학문영역으로 성장했다. 본 논문은 저온 플라즈마가 적용되고 있는 분야에 대해 소개하고, 플라즈마 메디신에 대한 이해를 돕고자 한다.

• Journal of Microbiology and Biotechnology
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• 제27권10호
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• pp.1783-1789
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• 2017

Thermostability is an important property of xylanase because high temperature is required for its applications, such as wood pulp bleaching, baking, and animal feedstuff processing. In this study, XynB from Thermobacillus composti, a moderately thermophilic gram-negative bacterium, was modified via site-directed mutagenesis (based on its 3D structure) to obtain thermostable xylanase, and the properties of this enzyme were analyzed. Results revealed that the half-life of xylanase at $65^{\circ}C$ increased from 10 to 50 min after a disulfide bridge was introduced between the ${\alpha}$-helix and its adjacent ${\beta}$-sheet at S98 and N145. Further mutation at the side of A153E named XynB-CE in the C-terminal of this ${\alpha}$-helix enhanced the half-life of xylanase for 60 min at $65^{\circ}C$. Therefore, the mutant may be utilized for industrial applications.

• 한국작물학회지
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• 제41권spc1호
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• pp.145-165
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• 1996

Amaranth(Amaranthus spp. L.) and quinoa (Chenpodium quinoa Willd.) are old crops from South, Central America and Central Asia and their grains have been identified as very promising food crops because of their exceptional nutritive value. Squalene is an important ingredient in skin cosmetics and computer disc lubricants as well as bioactive materials such as inhibition of fungal and mammalian sterol biosynthesis, antitumor, anticancer, and immunomodulation. Amaranth has a component called squalene (2,6,10,15,19,23-hexamethyl-2,6,10,14,22-tetraco-sahexaene) about 1/300 of the seed and $5\~8\%$ of its seed oil. Oil and squalene content in amaranth seed were different for the species investigated. Squalene content in seed oil also increased by $15.5\%$ due to puffing and from 6.96 to $8.01\%$ by refining and bleaching. Saponin concentrations in quinoa seed ranged 0.01 to $5.6\%$. Saponins are located in the outer layers of quinoa grain. These layers include the perianth, pericarp, a seed coat layer, and a cuticle like structure. Oleanane-type triterpenes saponins are of great interest because of their diverse pharmacological properties, for instance, anti-inflammatory, antibiotic, contraceptive, and cholesterol-lowering effects. It is known that quinoa contains a number of structurally diverse saponins including the aglycones, oleanolic acid, hederagenin, and phytolaccagenic acid, which are new potential in gredient for pharmacological properties. It is likely that these saponin levels will be considerably affected by genetic, agronomic and environmental factors as well as by processing. With the current enhanced public interest in health and nutrition amaranth and quinoa will most likely remain in the immediate future within the realm of exotic health foods until such time as agricultural production meets the quantities and qualify required by industrial food manufacturers.

• 한국환경과학회지
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• 제15권2호
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• pp.101-106
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• 2006

The work of hairdressers includes washing, coloring, bleaching, permanent waving, conditioning, and cutting hair. Hairdressers are subjected to a number of physical and toxicological hazards. The toxicological hazards are those resulting from exposure to a wide range of chemicals that are usually classified active processes. In this study, twenty beauty shops were selected to assess the exposure to indoor air pollutants such as VOCs and particulate matter $(PM_{10})$ during one month from September 1 to September 30, 2003. Indoor air quality of beauty shops might be worse by vehicle emissions because the beauty shops were generally located near roadways. Personal exposures to VOCs and $PM_{10}$ were related to indoor concentrations of beauty shops. According to the questionnaire, hairdressers complained of sore throat, eye irritation, and nervousness as physical symptoms. The measured mean concentrations of respiratory particulates were $30.5ng/m^3$ in indoor, $30.5ng/m^3$ in outdoor and $44.0ng/m^3$ on personal levels. The personal concentration was found higher than indoor and outdoor concentrations. The heavy metals mean concentrations were shown as indoor (Na>Zn>Cr), outdoor (Cr>Zn>Pb), and personal (Na>Cr>Zn) levels. Conclusively, customers as well as workers in the beauty shops might be highly exposed to air pollutants from indoor and outdoor sources. Therefore, proper management should be taken to improve the indoor air quality in beauty shops.

• 한국응용과학기술학회지
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• 제26권1호
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• pp.1-9
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• 2009

Nowadays, Tra catfish fat is given attention as an appropriate material for biodiesel production in Vietnam. The aim of this work is to investigate the optimal conditions of refining biodiesel and recovering glycerin by the transesterification from Tra catfish fat using KOH catalyst. As our results, the yield of transesterification was achieved to 94.17% at $50^{\circ}C$ for 45 min with 6:1 molar ratio of methanol to fat in the presence of 0.8% KOH catalyst, and wherein the biodiesel was refined by washing with distilled water at $70^{\circ}C$ and dried in a microwave oven. The yield of raw glycerin recoveries from the transesterification process was 78.58%. The purity of raw glycerin was 84.14% by the conditions of neutralization state with $H_{3}PO_{4}$ solution (pH = 5), $70^{\circ}C$, and 60 min. Activated carbon (3.0 wt.%) was used for the bleaching process at $80^{\circ}C$ for 20 min. The biodiesel was obtained in accordance with for ASTM D 6751 (biodiesel standard). The ash and water of raw glycerins were 7.32 and 8.01%, respectively, and implied that the raw glycerin is very promising candidate to be used as a raw material for textile and cosmetic industries.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2003년도 생물공학의 동향(XII)
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• pp.74-78
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• 2003

본 논문에서는 금속의 표면 플라즈몬 공명으로 인한 금속-유전체 경계면에서의 국소적 전자기장의 강화 효과를 이용하여 표면 플라즈몬을 유발하는 금 박막을 유리 기판위에 증착하고, 프리즘 커플러를 이용한 소산장의 공명 흡수현상을 이차원 영상 으로 얻었다. 특히 DNA/단백질 칩 등 향후 가능한 다채널 시스템에의 응용을 고려하여11-MUA, 11-MUOH 등 자기조립 단분자막(SAM)을 크롬 마스크와 리토그래피, 그리고 Shadow mask와 광 산화반응을 이용하여 금 표면 위에 패터닝 하였다. 텅스텐-할로겐 램프와 중심파장이 ${\lambda}_0=633$ nm의 대역통과 필터를 사용하여 이 평행광을 프리즘 커플러에 입사시켜 반사되어 나오는 반사광의 이차원 영상을 얻었다. 이와는 별도로 ${\lambda}_0=633$ nm의 레이저를 이용하여 단분자막이 코팅되어 있을 때와 없을 때의 공명각의 변화를 관찰하였다. 얻어진 이차원 영상의 위치에 따른 화소 값의 변화를 단분자 막의 두께의 변화에 따라 보정하고, 알려진 매질의 SPR 특성을 Fresnel 방정식에 따라 이론적으로 계산하면 다채널 표면 영상으로부터 항원-항체 등 단백질의 결합 정도를 정량적으로 측정할 수 있다.

• 한국식품조리과학회지
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• 제30권1호
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• pp.33-40
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• 2014

The purpose of this study was to examine the antioxidative activity of feral haw (Crataegus pinnatifida BUNGE) seed extracts using 70% methanol, 70% ethanol, chloroform:methanol (CM, 2:1, v/v), n-butanol and ethyl acetate (EA). The total phenol content of the five extracts ranged from 37.29 mg/g to 55.53 mg/g. Moreover, the content was high in the 70% methanol and, 70% ethanol extracts, but low in the n-butanol extract. On the contrary, the total flavonoid content decreased in the order of n-butanol (2.93 mg/g), EA (2.67 mg/g), 70% methanol (1.00 mg/g), 70% ethanol (0.88 mg/g) and CM (0.67 mg/g) extracts. The $NO_2$ radical scavenging activity, antioxidant activity by ${\beta}$-carotene bleaching assay and, superoxide dismutase (SOD) like ability decreased in the order of 70% methanol, 70% ethanol, CM, EA and, n-butanol extracts; further, a similar tendency was also observed in the total phenol contents. Overall, these results indicated that the antioxidative activity of feral haw seeds was closely related to the total phenol and flavonoid contents. Therefore, haw seeds might be usefully applied to natural antioxidants as well as functional foods.

• 한국식품과학회지
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• 제29권1호
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• pp.15-20
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• 1997

탈검, 탈산, 탈색과 탈취 등의 정제 과정이 참기름에 존재하는 항산화 물질과 금속의 함량에 미치는 영향과 $70^{\circ}C$에서 저장 중 참기름의 산화 안정성과 항산화물질의 변화에 관하여 시험하였다. 철, 구리, 마그네슘 및 아연의 금속은 탈검 과정에서 거의 대부분이 제거되었다. 조참기름과 탈검유는 저장 동안에 총 휘발성 화합물의 양에 거의 변화가 없었으며, 탈산유와 탈취유는 저장 초기에서부터 총 휘발성 화합물의 양이 현저하게 증가하였다. 동정된 휘발성 산화 생성물 중 hexanal과 pentanal의 변화가 가장 뚜렷하였으며, 탈산, 탈색과 탈취 등의 정제 과정을 거친 시료들은 저장 초기에 이러한 산화 생성물의 증가가 현저하였다. Sesamin은 정제와 저장동안에 비교적 안정하였고, sesamolin은 정제 과정과 저장 중에 뚜렷하게 감소하였다. Sesamol은 탈산 과정까지는 감소하다가 탈색 과정을 거치면서 급격히 증가하였고, 탈취 과정에서 거의 제거되었다. 저장 중 sesamolin이 계속 감소되면서 sesamol의 증가가 수반되었다.

• 한국잡초학회지
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• 제31권2호
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• pp.192-198
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• 2011

서해안 간척지대를 중심으로 최근에는 경기, 충청 지역까지도 문제가 되고 있는 다년생의 난방제 잡초인 SU계 제초제 저항성 새섬매자기에 대하여 pyrimisulfan+mefenacet SC, triafamone+tefuryltrione GR와 HPPD 저해제인 tefuryltrione GR를 SU계 제초제인 pyriminobac-methyl+pyrazosulfuron-ethyl GR와 대조약제로 하여 온실과 포장에서 확인하였다. 생육기의 새섬매자기에 대해서 온실 및 포장조건에서 pyrimisulfan+mefenacet SC와 triafamone+tefuryltrione GR은 SU계 제초제 저항성 새섬매자기에 대해 95% 이상의 방제효과를 보여주었다. 두 약제에 의해 새섬매자기는 생육이 억제되어 갈변, 괴사하였다. Tefuryltrione GR는 생육 초기에는 새섬매자기에 대해서 80% 내외의 약효와 백화 증상을 확인할 수 있었으나, 재생 및 후발아하는 새섬매자기에 대해서는 방제효과가 68%로 떨어졌다. 경기 김포, 평택, 충남 당진, 서산, 전남 해남 지역 등의 새섬매자기 다발생 지역에서도 pyrimisulfan+mefenacet SC는 발생 초기의 새섬매자기는 물론 생육기의 새섬매자기에 대해서도 우수한 방제효과를 보였다.