• Biomolecules & Therapeutics
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• 제8권2호
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• pp.147-152
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• 2000

The rodent uterotrophic assay is currently recommended as one of the primary in vivo assays far endocrine disrupting chemicals by the Organization for Economic Cooperation and Development (OECD) and Endocrine Disruptor Screening and Testing Advisory Committee (US EPA EDSTAC). Generally, this assay relies on the rapid increase in uterus and vagina weights when exposed to estrogenic compounds. Phthalate esters have been used extensively as a plasticizer in the manufacture of plastic products such as PVC films and medical devices. Recently, phthalate esters have been shown to induce endocrine system mediated responses. However, a flew studies have been conducted for the screening of their estrogenic activity. In this study the estrogenic activity of seven phthalate esters, butyl benzyl phthalate (BBP), di(2-ethylhexyl) phthalate (DEHP), di-n-butylphthalate (DBP), diethylphthalate (DEP), di-n-pentylphthalate (DPF), di-n-propylphthalate (DPrP) and dicyclohexylphthalate (DCHP), was examined in uterotrophic assay. Phthalate esters dissolved in corn oil were administered to ovariectomized (OVX) female Sprague-Dawley rats by sub-cutaneous injection for three consecutive days. fiats were sacrificed 24h after final treatment, and then uterus and vagina weights were deter mined. All phthalate esters tested in this assay did not change talc uterus and vagina weights at dosage levels up to 200 mg/kg/day treatment. These results demonstrated that phthalate esters did not exhibit estrogenic activity in vivo uterotrophic assay.

• 한국지역사회생활과학회지
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• 제23권3호
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• pp.255-263
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• 2012

Polybrominated diphenyl ethers (PBDEs) are a group of brominated flame retardants (BFRs), which are used in a variety of consumer products. Several of those are produced in large quantities. Their chemical structure similarities to polychlorinated dibenzo-p-dioxins and polychlorinated biphenyls (PCBs), as well as their toxicity, has been studied. PBDEs are persistent and lipophilic, which results in their bioaccumulation in the fatty tissues of organisms and enrichment throughout food chains. In addition, a number of studies also reported high levels of PBDEs in animals and food resulting from the use of contaminated animal feed Public concern about PBDEs levels in animals and food has been raised. Feed contamination by toxic chemicals has been the cause of the contamination of poultry products. The purpose of this study was to evaluate PBDEs in pig feed to search the origin chase of POPs in pigs. Feed samples were obtained wheat from East Europe, corn from South America and America, soybean meal from Korea, America, South America and India and tallow from Korea. The preparation of samples was based on the EPA method 1614. Instrumental analysis was based on the use of high resolution gas chromatography coupled to high resolution mass spectrometry (HRGC/HRMS). Quantification was carried out by the isotopic dilution method. The analysis of ${\Sigma}PBDEs$ involved 22 PBDE congeners, including BDE-17, 28, 47, 49, 66, 71, 77, 85, 99, 100, 119, 126, 138, 153, 154, 156, 183, 184, 190, 191, 196 and 197.

• Toxicological Research
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• 제19권1호
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• pp.1-12
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• 2003

New breeding method by genetic engineering is expected as a key technology to solve food shortage due to the growing world population in the year 2000s. Many genetically modified organisms (GMOs) were already developed and the commercial cultivation had started. The first GMO, Flavr Savr tomato, which rotted at a much slower pace than ordinary ones, was developed in US in 1994. Since then, over than 70 different agricultural products including corn, cotton, soybean, papaya, potato, and squash made with genetically modified plants are reportedly on sale worldwide. Supporters favor the GMOs because they have greater yields, longer shelf lives and stronger resistance to disease and insects. On the other hand, opponents say that the supporters ignore a potential danger that they may damage the environment as well as human beings. To assure the safe development and use of GMOs as food and other biotech products, the possible risks on biological environment and human health should be throughly examined and regulated by developer and government. Because the biosafety problem is a global, environmental, and trade issue, a new international treaty is under development. The Cartagena Protocol on Biosafety was adopted at the 1 st Extraordinary Conference of Parties of the Convention on Biological Diversity which was held at Mont-real, Canada, Jan. 29th, 2000. The adoption of the Protocol is seen as a breakthrough in that it is based on the" Precautionary Principle" despite scientific uncertainties surrounding potential risks that GMOs may inflict on human health and the environment and that it has laid the ground for introduction of specific steps to handle international trading of GMOs. In this paper, the authors would like to introduce the current status and perspective of environmental and human risk assessment of GMOs.t of GMOs.

• 한국초지조사료학회지
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• 제22권2호
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• pp.107-114
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• 2002

본 실험에서는 볏짚에 사과박의 첨가비율을 달리하여 조제한 사일리지(볏짚:사과박 = 100:0, 80:20, 60:40, 40:60) 혹은 옥수수 사일리지에 건초 및 시판사료의 혼합 비율을 각각 40:40:20로 조제하여 한국 재래산양에게 급여하였고, 이들에 의한 사료섭취량, 소화율 및 질소 축적율 등을 조사하여 농산 가공 부산물의 사료화 가능성을 제시하고자 실시하였으며 그 결과를 요약하면 다음과 같다. 시험사료의 화학적 조성분은 조단백질 함량이 6.3∼7.3%이었고 ADF, NDF 및 조회분 함량은 볏짚 혼합비율이 100%(A구)가 각각 39.4, 61.6 및 8.9%로 가장 높았으며 옥수수 사일리지 급여구(E구)가 30.3, 53.4 및 4.9%로 가장 낮은 경향을 보였으나, NSC 함량은 E구가 31.4%로 가장 높았다. 1일 두당 건물섭취량 및 대사체중 당 건물 섭취량은 사과박 혼합 비율이 가장 많은 D구가 각각 605.3과 69.5g으로 옥수수 사일리지 급여구인 E구의 394.0과 46.8g보다 유의하게 높았다.(p<0.05). 일당 증체량은 사과박 혼합비율이 40(C구)과 60%(D구)에서 각각 16.7과 22.9g으로 사과박 혼합비율이 0(A구)과 20%(B구)의 0.17과 4.3g보다 유의하게 높았다(p<0.05). 건물 및 유기물 소화율은 D와 E구가 A와 B구 보다 유의하게 높았으며 ADF와 NDF 소화율도 D구가 각각 50.2와 57.4%로 A, B 및 E구 보다 유의하게 높았다(p<0.05). 질소 축적량과 축적율은 사과박 혼합 비율이 가장 높은 D구가 각각 1.4g과 20.4%로 가장 높았으며 A구가 -0.3g과 -7.75%로 가장 낮았다.

• Journal of the Korean Wood Science and Technology
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• 제38권6호
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• pp.547-560
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• 2010

본 연구에서는 Schizophyllum commune의 당 분해효소 생산을 위한 최적 배양 조건과 목질바이오매스에 대한 당화 특성에 대하여 연구하였다. S. commune 균체 외 효소에는 endo-${\beta}$-1,4-glucanase (EG), cellobiohydrolase (CBH), ${\beta}$-glucosidase (BGL)와 같은 cellulase와 ${\beta}$-1,4-xylosidase (BXL)이 함유되어 있고 그 중에서 EG 및 BGL활성이 비교적 높은 활성을 나타낸 것으로 밝혀졌다. S. commune에서 생산된 EG, BGL, 및 CBH의 최적 온도는 $50^{\circ}C$이었으나, 열안정성을 가지는 온도범위는 $30{\sim}40^{\circ}C$였다. 그리고 최적 pH는 5.5이었으며 열 안정성을 나타내는 온도범위에서의 적정 pH는 동일한 pH 5.5이었다. Cellulase 생산을 위한 S. commune의 최적배양 조건은, 탄소원으로 천연 cellulose, 질소원으로는 corn steep, 또는 peptone/yeast extract 혼합물, 비타민은 첨가하지 않는 것이 cellulase 효소활성 증가에 적절한 것으로 밝혀졌다. 또한 탄소원의 최적 첨가 농도는 2% (w/w), 적정 배양 pH 및 온도는 5.5~6.0과 $25{\sim}30^{\circ}C$로 밝혀졌다. 본 연구에서 도출된 최적 배양 조건으로 S. commune를 배양시키고 40배로 농축한 결과, EG가 3670.5 U/$m{\ell}$, BGL과 CBH가 각각 631.9 U/$m{\ell}$, 398.5 U/$m{\ell}$, BXL이 15.2 U/$m{\ell}$로 매우 높은 효소 활성을 나타냈다. 동일한 효소의 Filter Paper Unit도 11 FPU/$m{\ell}$로 상당히 높았다. 최적배양조건에서 얻어진 S. commune 효소로 다양한 기질에 대해 당화 시험을 실행한 결과, 전처리를 하지 않은 공시 활엽수에 대하여 낮은 당화율을 나타냈으나 천연 cellulose (Aldrich, ~20 micron) 및 볏짚의 경우에는 각각 50.5% 및 33.1%의 높은 당화성능을 나타냈다. 이 같은 당화 수준은 동일 효소농도 (30 FPU/g, glucan)로 비교했을 때 Trichoderma reesei 유래 상용화 효소인 Celluclast 1.5L의 약 110% 수준을 나타냄으로써, 대량생산기술 개발과정을 통해 목질계 당화 효소로의 상용화 가능성이 높은 균주로 평가되었다.

• Journal of Nutrition and Health
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• 제31권2호
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• pp.153-158
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• 1998

The purpose of this study was to investigate the effect of vitamin E supplementation on the lipid peroxidation and activities of antioxidative enzymes in the pancreas of diabetic KK mice. KK mice were fed high ft diet containing 20% corn oil(wt/wt), and sacrificed at 2 months of diabetes. A hish vitamin E diet consisted of the high fat diet supplemented with an excessive amount of 이-$\alpha$-tocopheryl acetate (2080IU/kg diet). The incidence of diabetes mellitus was 61% when mice were fed the high fat diet, but was 44% when mice were fed the high vitamin E diet, Vitamin E supplementation fhus seems to have the effect of decreasing of decreasing the onset of diaetes. In the diabetic group, we found increases of MDA (malondialdehyde) and antioxidative enzyme activities. Treatment with vitamin E did not modify the level of fasting blood glucose. However, MDA and antiosicative enzyme activities in diabetic mice were decreased by the high vitamin E diet. Increased levels of lipid peroxidation products suggests the occurrence of oxidative damage in the pancreas of diabetic mice. The increased level of antiosicative enzyme activities could be due to an adaptive response to conditions of increased peroxidative stress. Significant normalization on catalase activity was noted in vitamin E supplemented animals.

• 한국수산과학회지
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• 제44권1호
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• pp.37-44
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• 2011

We investigated the optimum formulation to improve the gelling ability of squid, Dosidicus gigas, surimi. The solubility of minced squid muscle was highest at pH 10.7, and lowest at pH 5.0. The yields of conventional surimi and protein recovery after alkaline pH-shift processing were $68.1{\pm}2.4%$ and $65.3{\pm}2.6%$, respectively, whereas the protein recovery with acidic pH-shift processing was only $21.2{\pm}1.6%$. The addition of 5% starch decreased the breaking force regardless of the kind of starch, while the mixture of corn, potato, and wheat starch (total 15%) increased the breaking force by up to 1.9 fold. The addition of 5% egg white, 5% porcine plasma protein, 0.3% $CaCl_2$, and 0.3% Polymix GA significantly increased the breakingforce (P<0.05). None of the ingredients examined in this study significantly affected the deformation value (P<0.05). The optimum concentrations of egg white and $CaCl_2$ to obtain a breaking force of 55 g and a whiteness of 70 were 2.69% and 0.22%, respectively.

• Journal of Biosystems Engineering
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• 제19권2호
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• pp.91-98
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• 1994

Planting, transplanting, and harvesting are important processes for the successful production of farm products in Korea because those require the high labor intensity during limitted period. Recently, many researches of using automatic control with a microcomputer are carried in the agricultural field, but are not much spread to the seeder development. Automatic sowing technology would be much attractive if there was a way to assure that each seed was count accurately in the seed metering device. Thus, an automatic seed metering device was designed and constructed to be controlled by microcomputer. This device could be improved in not only counting the number of seeds in but also sowing seeds between row spacings. Automatic seed metering device consisted of conveyor belt and temporary storage device. Performance of seed metering device depends on the apparatus including sensor, stepping motor and DC-solenoid. Research contents and results are summarized as follows. 1. The seed metering device involving seed hopper, sorter and temporary storage device was designed and constructed. 2. A seed counting system with six photo electric sensors, designed and built for this project, was adequate for tranferring and counting seeds accurately. 3. Operating algorithm for stepping motor and photo electric DC-solenoid was developed. The Seed metering device proved to be a smooth and accurate operating device using the algorithm. 4. The performance of second prototype metering device was examined with five kinds of seeds ; mung beans, red beans, white beans, black beans and corn to transfer and count the seeds. The error ratio of seed metering was less than 3.5%.

• 한국식품조리과학회지
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• 제20권6호
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• pp.614-618
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• 2004

늙은 호박을 이용하여 기능성 있는 양갱을 제조하기 위하여 호박 페이스트의 양을 $87\%$(A제품), $90\%$(B제품), $93\%$(C제품)로 비율을 달리하여 한천, 설탕, 물엿, 소금을 이용한 3가지 호박양갱 제품을 제조하여 영양성분을 분석한 결과는 다음과 같다. 아미노산은 glutamic acid와 aspartic acid가 가장 높게 나타났고, 비타민 E는 C 제품이 A와 B제품에 비하여 유의적으로 높게 나타났다. 또한 구성 당 함량에서는 glucose와 galactose는 C제품이, fructose와 lactose는 A제품이 다른 제품에 비하여 유의적으로 높게 나타나 대조를 이루었다. 무기질 중 다량원소인 칼슘, 마그네슘, 칼륨과 나트륨은 C제품이, 미량원소인 아연과 망간은 A제품이 가장 높게 나타났다. 특히 칼륨의 함량이 다른 무기질에 비하여 가장 높게 나타났다.

• BMB Reports
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• 제37권4호
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• pp.422-428
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• 2004

Raw-starch-digesting $\alpha$-amylase (Amyl III) was purified to an electrophoretically pure state from the extract of a koji culture of Aspergillus awamori KT-11 using wheat bran in the medium. The purified Amyl III digested not only soluble starch but also raw corn starch. The major products from the raw starch using Amyl III were maltotriose and maltose, although a small amount of glucose was produced. Amyl III acted on all raw starch granules that it has been tested on. However, it was considered that the action mode of the Amyl III on starch granules was different from that of glucoamylase judging from the observation of granules under a scanning electron microscope before and after enzyme reaction, and also from the reaction products. Glucoamylase (GA I) was also isolated and it was purified to an electrophoretically pure state from the extract. It was found that the electron micrographic features of the granules after treatment with the enzymes were quite different. A synergistic effect of Amyl III and GA I was observed for the digestion of raw starch granules.