곡류와 그 가공품에서 Deoxynivalenol과 Zearalenone의 분석

옥현이,장현주,최성욱,이나리,김현정,구민선,전향숙 한국식품위생안전성학회 2007 한국식품위생안전성학회지 Vol.22 No.4

(DON) and zearalenone (ZEN) are naturally occurring toxins produced by Fusar-ium species, which may grow on cereals. The aims of this study were to determine the incidence and contaminationlevels of DON and ZEN in cereal products. Seventy samples of cereal products were randomly selected from retailoutlets during 2005 and 2006. DON and ZEN were analyzed by using high performance liquid chromatography withfluorescence and UV-detector, respectively. Detection limits were 4.4 g kg-1 for DON and 3.4 g kg-1 for ZEN. DONand ZEN were detected in 37 and 17, respectively, of the 70 samples, but the levels found were very low. In particular,out of 70 samples, 12 samples of corn and barley were co-contaminated with DON and 5.6 to 1842.3 g kg-1 for DON and 12.1 to 174.9 g kg-1 for ZEN, respectively. However, DON and ZEN were notdetected in breakfast cereals and wheat flour. The highest level was found in dried corn kernel samples that confirmedby LC-MS. This study show that DON and ZEN co-contaminate with low levels in cereal products.

면류에서 HPLC를 이용한 데옥시니발레놀 분석법의 검증과 불확도 산정

옥현이,전향숙,장현주,강영운,김미혜 한국식품위생안전성학회 2011 한국식품위생안전성학회지 Vol.26 No.2

An isocratic high performance liquid chromatography (HPLC) method for routine analysis of deoxynivalenol in noodles was validated and estimated the measurement uncertainty. Noodles (dried noodle and ramyeon) were analyzed by HPLC-ultraviolet detection using immunoaffinity column for clean-up. The limits of detection (LOD) and quantification (LOQ) were 7.5 μg/kg and 18.8 μg/kg, respectively. The calibration curve showed a good linearity, with correlation coefficients r² of 0.9999 in the concentration range from 20 to 500 μg/kg. Recoveries and Repeatabilities expressed as coefficients of variation (CV) spiked with 200 and 500 μg/kg were 82 ± 2.7% and 87 ± 1.3% in dried noodle, and 97 ± 1.6% and 91 ± 12.0% in ramyeon, respectively. The uncertainty sources in measurement process were identified as sample weight, final volume, and sample concentration in extraction volume as well as components such as standard stock solution, working standard solution, 5 standard solutions, calibration curve,matrix, and instrument. Deoxynivalenol concentration and expanded uncertainty in two matrixes spiked with 200 μg/kg and 500 μg/kg were estimated to be 163.8 ± 52.1 and 435.2 ± 91.6 μg/kg for dried noodle, and 194.3 ± 33.0 and 453.2 ± 91.1 μg/kg for ramyeon using a coverage factor of two which gives a level of statistical confidence with approximately 95%. The most influential component among uncertainty sources was the recovery of matrix, followed by calibration curve.

쥐 간세포 배양을 위한 무혈청 배지의 개발

임진옥,노숙령,이재관,옥현이 中央大學校 遺傳工學硏究所 1995 遺傳工學硏究論集 Vol.8 No.1

A study regarding serum-free media for the culture of rat primary hepatocyte was investigated. The effect of L-proline on the hepatocyte funtional activity was studied by measuring the hepatocyte differentiate functions. The addition of L-proline enhanced the amino acid metabolism by hepatocyte, especially, the rate of L-glutamine consumption was increased by 2-fold. The supplementation of L-proline replaced the requirement of serum in media. In serum-free media, L-proline supplementation supported the functional activity of hepatocyte for 7 weeks, and the albumin secretion rate was 6㎍/hr/2×10(6)cells. Kinetic measurement of DNA showed that the role of L-proline was not the stimulation of hepatocyte growth. Also, the requirement of L-proline in hepatocyte culture was specific for the sandwich configuration. Finally, in protein-free media without hormons or growth factors was maintained hepatic activity for 2 weeks. Summarized all together, L-proline is a indispensible factor in serum-free hepatocytes culture.

안전진단 업무프로세스 모델 구축과 활용방안에 관한 연구 ( A Development of Process Model and Application for Building Safety Inspection )

옥현,진상윤 대한건축학회 2000 大韓建築學會論文集 : 構造系 Vol.16 No.7

Caffeine과 Acetaminophen으로 인한 간독성과 항산화성 비타민의 효과

옥현이(Hyun-Ee Ok),노숙령(Sook-Nyung Rho),이재관(Jae-Gwan Lee) 한국식품영양과학회 1997 한국식품영양과학회지 Vol.26 No.6

간세포에서 caffeine과 APAP의 독성 효과를 알아보기 위해 in vitro 에서 suspension culture 방법을 이용하였고 간독성의 지표로 glutathione, malondialdehyde를 측정하였다. 또 monolayer culture에서 hepatocyte morphology를 관찰하였으며 위의 두가지 성분과 함께 항산화성 비타민인 α-tocopherol, β-carotene, ascorbic acid를 투여해 본 결과는 다음과 같았다. 체외배양된 hepatocyte에서 caffeine과 APAP를 각각 투여하였을 때 caffeine만으로는 MDA생성과 GSH고갈이 대조군과 비슷하고 APAP는 농도에 따라 세포내 GSH함량을 감소시키나 MDA생성에 있어서는 대조군과 뚜렷한 차이를 보이지 않았다. 그러나 caffeine과 APAP를 함께 투여하면 caffeine과 APAP의 농도가 증가할수록 GSH 함량은 유의적으로 감소하고 MDA생성은 상당히 증가하여 동시 투여가 단독 투여보다 간세포에 더 큰 손상을 끼치는 것으로 여겨진다. Caffeine과 acetaminophen으로 인한 간세포의 손상정도를 광학현미경으로 관찰해 본 결과 acetaminophen의 농도가 증가할수록 미립이 많이 형성되어 세포막의 통합성이 떨어지는 것으로 볼 수 있었고 vit E 5μM을 첨가하였을 때는 이러한 현상이 감소함을 알 수 있었다. 그리고 caffeine과 APAP의 동시 투여로 간독성을 유발할 수 있는 상황에 비타민인 α-tocopherol, β-carotene, ascorbic acid를 첨가하였을 때 이들 모두 항산화제로서 간세포를 보호하였고 α-tocopherol이 더 효율적으로 GSH의 고갈을 억제하였다. Hepatotoxicity of caffeine and acetaminophen was investigated in this study. Special attention was paid to the effect of vitamins on the reduction of hepatotoxicity caused by the chemicals. Rat hepatocytes isolated by two-step perfusion method were cultured in two different methods-suspension, monolayer cultures-, and exposed to caffeine and/or acetaminophen for 24hrs. Caffeine or acetaminophen exhibited no significant hepatotoxicity in terms of intracellular glutathione(GSH) level and lipid peroxidation(MDA), but GSH level was significantly decreased after administrated acetaminophen, and the toxicity caused by the chemicals showed a dose-dependent manner. The synergistic effect of caffeine and acetaminophen was observed when both caffeine and acetaminophen were supplemented to culture medium. At the concentration 1mM, caffeine enhanced the intracellular GSH depletion and MDA formation by 63% and 64%, respectively, compared to single supplementation of 10mM acetaminophen in culture medium. This hepatotoxicity induced membrane integrity loss was observed by lightmicroscope on the simultaneous administration of caffeine and acetaminophen in monolayer cultured hepatocytes. Co-supplementation of vitamins with caffeine/acetaminophen to culture medium results in the protection of hepatocytes from hepatotoxic attach by caffeine/acetaminophen. Especially, vitamin E was superior to vitamin C and β-carotene from the standpoints of GSH depletion and MDA formation. From this results, it has been speculated that vitamin E may play a role of antioxidant scavenging radicals produced from acetaminophen. Taken all together, in vitro culture system like monolayer culture of hepatocytes may be a useful tool for the evaluation of hepatotoxicity or protection ability of food ingredients.

밀에서 HPLC에 의한 데옥시니발레놀 분석의 측정불확도 산정

옥현이(Hyun Ee Ok),장현주(Hyun-Joo Chang),안장혁(Jang-Hyuk Ahn),조재용(Jae-Young Cho),전향숙(Hyang Sook Chun) 한국식품과학회 2009 한국식품과학회지 Vol.41 No.3

본 연구에서는 밀 시료에서 면역친화컬럼을 이용한 HPLC분석법으로 데옥시니발레놀을 분석함에 있어서 발생될 수 있는 측정 불확도를 GUM 지침에 따라 산정하였다. 분석과정에서의 불확도 요인은 시료량 측정, 최종 시료부피, 보관표준용액, 작업표준용액, 표준용액, 기기, 매질, 검량선 작성으로 구분하였다. 불확도 요인의 구성요인은 저울의 안정성, 분해능, 재현성, 표준물질의 순도, 분자량, 농도, 표준용액 희석, 검량선, 회수율 및 분석기기의 재현성 등이 작용하였다. 공시료에 데옥시니발레놀 300 μg/kg을 첨가하여 분석한 결과 255.29±71.62 μg/kg으로 측정되었다. 확장불확도는 합성표준불확도 35.81 μg/kg에 포함인자(k=2, 신뢰수준 95%)를 곱하여 산출하였다. 밀에서 데옥시니발레놀을 분석함에 있어 불확도에 영향을 주는 주요인자는 시료의 회수율과 검량선 작성인 것으로 파악되었다. 따라서 밀 시료에서 데옥시니발레놀 분석의 정밀성을 높이기 위해서는 회수율과 검량선 작성에 영향을 끼칠 수 있는 면역친화컬럼에 의한 시료의 정제과정과 표준물질의 희석과정에 주의를 기울이고 주기적으로 마이크로피펫을 교정하는 등 세심한 관리가 필요할 것으로 판단된다. The principal objective of this study was to estimate the measurement uncertainty associated with determination of deoxynivalenol (DON), a mycotoxin generated by Fusarium strain, in food. In service of this goal, wheat as a food matrix was analyzed via high performance liquid chromatography-ultraviolet (HPLC-UV) detection using an immunoaffinity column for clean-up. The uncertainty sources in the measurement process were identified by sample weight, final volume, and sample concentration in extraction volume with components including standard stock solution, working standard solution, 5 standard solutions, calibration curve, matrix, and instrument. The expanded uncertainty for DON at a concentration of 300 μg/kg was estimated as 71.62 μg/kg using a coverage factor of two, which provides a confidence level of approximately 95%. The most influential component in the uncertainty sources was the recovery of the wheat matrix, followed by the calibration curve. These results indicate that all efforts may be directed toward reducing the uncertainties of the recovery of the wheat matrix and the calibration curve to obtain a reliable HPLC-UV method for DON analysis in wheat.

공공 도로건설사업에서의 원격 현장모니터링 체계 구축에 관한 연구

옥현 한국도로학회 2012 한국도로학회논문집 Vol.14 No.6

PURPOSES : Efficiency Improvement of a public road construction project management work using the development of a real-time remote site monitoring system METHODS : In this study, we developed the remote site monitoring system using a web camera for road construction projects in the RCMA(Regional Construction Management Administration). we can be monitored a construction progress and a weak point of the situation in real time using this. To achieve this, we tested about 10 road construction projects ordered by RCMA. Then, we verified a applicability for the site monitoring system in future. RESULTS : Take advantage of the remote site monitoring system consists of the construction CALS system, one of the business systems used in the part of the MLTM(Ministry of Land, Transport and Maritime Affairs) institution․agencies. Was configured to be served through the “Construction CALS System” of “Construction Management System(Contractors)” and the “Construction CALS Portal System”. Through this, Benefit analysis through a pilot application of the 10 road construction sites and developing considerations and “Guide for visual information processing equipment installation·operating in construction sites” are presented. CONCLUSIONS : Through the establishment of remote site monitoring system can improve the efficiency of construction management services. In addition, Various disasters and calamities, accidents and illegal construction will be prevented in advance is expected. This is expected to further improve the quality of the facilities.

도로분야의 건설정보모델(BIM) 실무 매뉴얼 개발방안에 관한 연구

옥현,권바름,김성진,김태학,주기범 한국도로학회 2019 한국도로학회논문집 Vol.21 No.6

PURPOSES : The Ministry of Land, Infrastructure and Transport (MOLIT) and its subordinate agencies have recently established various policies for the application of BIM and are implementing these policies, and are increasing project orders with the application of BIM. Developed countries where they have earlier adopted BIM provide BIM standards and guidelines at the national level to support BIM implementation by private-sector constructors. Domestic BIM standards and guidelines, however, have been lacking details on upper-level standards that have to be presented by ordering agencies, thereby limiting the practical application thereof. This study aims to provide BIM practice manual development measures to ensure the facilitation of the writing of BIM outputs and their delivery in the road sector. METHODS: This study first analyzed domestic BIM standards and guidelines, and examined BIM processes in the existing BIM guidelines to determine the major works required in each stage of the implementation of road construction projects. Further, the study determined those matters that were required in working BIM but were not specified in existing BIM guidelines. Those derived contents have been reflected in the definition of the configuration system in the table of contents of the BIM practice manual, and in the contents on the road sector, and the details of each configuration system have been specified. RESULTS : The proposed BIM practice manual for the road sector is a technical guide on BIM guidelines published by public ordering agencies, and provides the basic requirements and methods required for the writing of BIM models. Further, the manual provides working procedures and detailed methods for writing BIM to enable working-level staffers on BIM projects to construct BIM data. The proposed BIM practice manual was configured with considerations for domestic civil-sector BIM technology levels and will be further developed and improved according to the development of domestic BIM technology. CONCLUSIONS : In an effort to respond to the changing domestic construction technology environment, and to apply and activate BIM, this study analyzed domestic BIM standards and guidelines, and defined a working BIM manual configuration system and its detailed configuration method. The findings and improvements are presented as a BIM practice manual on development measures in the road sector. This manual is expected to minimize the repetitive trials and errors and design errors in the construction of road-sector BIM models, to improve the productivity and efficiency in the creation of BIM outputs and their delivery, and to enhance the quality and utilization of the outputs. Further, the proposed manual is expected to provide and share information on the practical cases for BIM, to bolster the capabilities of design engineering, to ensure the linkage with relevant agencies, and thus to expand the diffusion of BIM in a virtuous cycle.

공공 도로건설사업에서의 설계도서 납품체계 개선방안에 관한 연구

옥현,김성진,김태학,주기범 한국도로학회 2018 한국도로학회논문집 Vol.20 No.2

PURPOSES : This study aims to survey and analyze the status of the design and completion documents output delivery system in public construction projects in order to assess the problems of the Ministry of Land, Infrastructure and Transport (MOLIT)'s electronic delivery system, with a focus on roads and rivers, and to offer improvement measures. METHODS: This study first surveys and analyzes laws and existing study trends with regard to the design and completion documents output delivery system in public construction projects. It further analyzes the status of the output delivery system in public construction projects, including roads, rivers, expressways, water resources, and railroads. In addition, a comparative analysis of the current electronic delivery system of MOLIT and Korea Expressway Corporation in the road field is conducted, and the problems and improvement measures for MOLIT's electronic output delivery system are presented. This study seeks to analyze problems and prepare improvement measures with regard to road and river public construction projects, as ordered by MOLIT’s five regional offices. RESULTS: This study sought to prepare the electronic output delivery system with regard to public construction projects and present the analysis of its major problems and improvement measures in four categories: “the preparation of electronic design documents output delivery system improvement measures including inspection and delivery,”“preparation of guidelines, systems, etc., concerning electronic design documents,”“preparation of improvement measures for the construction project management system and electronic design document support tools”, and “linking of MOLIT's electronic output delivery system with relevant agencies and the expansion thereof to local governments.” CONCLUSIONS : This study analyzed the current status and problems of the MOLIT's electronic output delivery system in the field of road and river construction projects, and presented corresponding improvement measures. This study is expected to address the problems of the MOLIT's electronic output delivery system, and to provide the foundation for the preparation of an efficient electronic output delivery system for design and completion documents. In addition, this study is expected to boost the quality and utilization of the electronic design documents output, and to exchange, share, and link construction information among relevant agencies so as to prepare the foundation for sharing construction information.

도로분야 건설정보모델(BIM) 성과품 작성·납품지침의 개발방안 제시에 관한 연구

옥현,김성진,김태학,주기범 한국도로학회 2019 한국도로학회논문집 Vol.21 No.1

PURPOSES : With the recent change to domestic and overseas construction technologies, which led to the adoption and application of threedimensional building information management (BIM), a BIM output delivery operation system is needed for the civil engineering infrastructure category. This study analyzes the domestic and overseas BIM-order placement, BIM-related guidelines/guides, and the BIM output delivery system for the road construction project category to present guideline development measures for BIM output writing and delivery. METHODS: This study surveys and analyzes the domestic BIM-related research trends to examine the domestic-infrastructure BIM-order placement situations in public ordering agencies. Additionally, it analyzes the domestic BIM-related guides and guidelines and existing twodimensional electronic delivery systems and the domestic and overseas BIM output delivery systems. This study defines the guideline composition system and direction to present criteria for BIM output writing, delivery, management, and utilization in the road category. Furthermore, it presents guideline composition measures for BIM output writing and delivery to propose detailed criteria, output-list composition, and output inspection procedures. RESULTS : This study presented BIM output guideline development measures for planning BIM output writing and delivery and management/utilization measures in the road category. To that end, it determined the domestic and overseas BIM guide and guideline composition systems, BIM ordering criteria, BIM data writing and delivery criteria, BIM output management and utilization measures, and a common BIM output list to present suitable detailed criteria. CONCLUSIONS: This study sought to respond to changes to the domestic and overseas construction environment and to present output writing/delivery guidelines as activation measures supporting the adoption and application of BIM. To that end, we analyzed the domestic and overseas BIM guidelines and guides, task instructions, bid information, etc. to define the appropriate composition system and to give it direction. We defined the contents of tables and detailed descriptions to present guideline development measures for BIM output writing/delivery guidelines in the road category. This is expected to improve work efficiency for BIM and to enhance output quality and utilization. Furthermore, the adoption of BIM in the road category will provide an infrastructure environment with which to exchange BIM information with related agencies. We plant to further develop verification tools for the Ministry of Land, Infrastructure, and Transport's BIM model projects, for their output writing and delivery, and for an integrated BIM platform that will continue to improve the proposed criteria.