• 치위생과학회지
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• 제18권6호
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• pp.367-373
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• 2018

시판 중인 어린이 음료가 레진계 치면열구전색제에 미치는 물리 화학적 영향을 알아보기 위해 판매량이 높은 3종의 어린이 음료와 대조군으로 생수를 선정하였다. 제조사의 지시에 따라 레진 시편을 제작하여 시편의 초기 거칠기 값(Ra)를 측정하였고, 각 음료의 pH를 측정한 후, 레진 시편을 각각의 음료에 침지시켜 $37^{\circ}C$ 배양기에서 72시간 보관하였다. 72시간 후 레진 시편의 표면 거칠기를 측정하였고 시편 표면의 형태변화 관찰을 위해 주사전자현미경으로 관찰하였다. 레진 시편에서 용출된 단량체의 종류 및 용출량은 HPLC를 이용하여 비교 분석하였다. 생수를 제외한 모든 실험음료에 구연산이 첨가되어 있었고 어린이 음료의 평균 pH는 $3.25{\pm}0.17$로 '아이키커'에서 $3.03{\pm}0.01$로 가장 낮았고 '뽀로로'에서 $3.47{\pm}0.02$로 가장 높았다. 어린이 음료에 침지 후 시간 경과에 따른 표면 거칠기가 증가하였고 레진 시편의 표면에 기질의 탈락을 관찰하였다. 모든 실험음료에서 bis-GMA는 유출되지 않았으나 생수를 제외한 어린이 음료에서는 TEGDMA가 유출되었다. 이상의 결과 어린이 음료는 치면열구전색제의 열화와 단량체의 유리를 촉진할 수 있으며 유리된 단량체는 성장 중인 어린이에게 더 큰 영향을 미칠 수 있으므로 어린이 음료를 빈번히 음용하는 것은 주의가 필요하다.

• 현장농수산연구지
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• 제25권2호
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• pp.12-19
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• 2023

한국농수산대학교 공정육묘실에서 인삼을 종자 파종하여 생장한 인삼 1년근을 각 실험구(공정육묘실, 관행 노지)에 이식 전 1차 생장 조사를 하고, 3개월 생육 후 2차 생장 비교조사를 하였다. 1차 생장 조사 결과, 이식 전 뿌리의 무게는 평균 0.95g에서 이식 후 관행 노지는 0.21g, 공정육묘실은 0.29g으로 증가하였다. 뿌리의 길이는 평균 13.85cm에서 이식 후 관행 노지는 2.03cm, 공정육묘실은 2.66cm로 증가하였다. 뿌리의 지름은 평균 5.58mm에서 이식 후 관행 노지는 1.04mm, 공정육묘실은 1.26mm로 증가하였다. 공정육묘실에서 생육한 인삼이 관행 노지재배보다 더 많은 생장이 확인되었다. 공정육묘실에서 생육한 인삼과 진안 농가 관행 노지재배 인삼의 진세노사이드 성분함량 비교를 위해 각 1년근, 2년근의 진세노사이드 11종(Rg1, Re, Rf, Rh1(S)+Rg2(S), Rb1, Rc, Ra1, Rb2, Rb3, Rd, Rg3)의 함량 비교한 결과, 진세노사이드 1종 전체 함량이 공정육묘실 재배 인삼 1년근에서는 17.32mg/g, 공정육묘실 재배 인삼 2년근에서는 16.43mg/g, 관행 노지재배 1년근에서는 5.84mg/g, 관행 노지재배 2년근에서는 6.17mg/g으로 확인되었다. 관행 노지재배 인삼 1년근, 2년근보다 공정육묘실 1년근, 2년근이 2배 이상으로 더 많은 진세노사이드 함량이 HPLC 분석 결괏값으로 확인되었다. 결론적으로 관행 노지재배 묘삼은 자연환경 아래에서 재배환경의 다양한 요인에 의한 생장이 작용하는 반면 공정육묘는 생장이 우수한 인공토 비율과, 식물 영양액 농도 EC1.0ms/cm로 수분을 공급하여 안정된 생장을 할 수 있고, 식물 생장에 필요한 온도, 광, 수분의 환경제어가 가능한 상태에서 생장하므로 묘삼의 생장 안정성을 확보할 수 있어 향후 이에 관한 지속적인 연구가 필요하다.

• 한국식품영양과학회지
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• 제37권6호
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• pp.752-760
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• 2008

One liter stirred-tank batch reactor에서 기질들의 부피 비율을 1:2:7(fully hydrogenated soybean oil : SL-olive+CLA : palm oil)하고 RM IM lipase를 사용하여 CLA를 함유한 재구성 지질을 합성하였다. 합성된 재구성지질은 총 CLA를 7.6 area% 함유하였고, 주요 지방산 조성은 oleic acid (38.1 area%), palmitic acid(33.1 area%), stearic acid(12.2area%) 및 linoleic acid(7.3 area%)로 분석되었으며 트랜스지방산은 분석한계 미만(0.1 area%)으로 검출되었다. Reversed-phase(RP) HPLC 분석 결과, 재구성 지질의 TAG 형태는 PN=44(1.52 area%), PN=46(21.79 area%), PN=48(53.71 area%) 및 PN=50(11.1 area%)의 범위로 나타내었다. 합성된 지질의 토코페롤 함량을 분석한 결과는 ${\alpha}$, ${\gamma}$-토코페롤이 각각 4.7, 1.0 mg/100 g로 반응기질보다 감소하였고, 이의 산가, 비누화가, 요오드가의 측정 결과는 각각 0.4, 173.9, 59.0이었다. 재구성 지질의 융점은 세 개의 피크를 보이며 각각 8.7, 25.3 및 $40.9^{\circ}C$으로 나타났고 결정화점은 각각 0.7, $18.2^{\circ}C$로 분석되었다. 또한 고체지 함량은 31.8%($25^{\circ}C$), 22.3%($30^{\circ}C$), 13.9%($35^{\circ}C$)를 나타내어 상업적인 쇼트닝과 유사한 물성을 보였다. 재구성 지질의 녹는점은 $39.8^{\circ}C$로 측정되었고, hardness value는 63.8 g로 분석되었다.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2010년도 춘계학술대회 초록집
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• pp.251.2-251.2
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• 2010

Plant biomass has been proposed to be an alternative source for petroleum-based chemical compounds. Especially, phenolic chemical compounds can be obtained from lignin by chemical depolymerization processes because lignin consists of complex aromatic polymer such as trans-p-coumaryl, coniferyl and sinapyl alcohols, etc. Phenolic chemical compounds from lignin were usually produced in super critical water. However, we applied Near-critical water (NCW) system because NCW is known as a good solvent for lignin depolymerization. Organic matter like lignin can be solved in NCW system and the system has a unique acid-base property without conventional non-eco-friendly chemicals such as sulfuric acid and sodium hydroxide. In this work, we tried to optimize the NCW depolymerization system by adjusting the processing variables such as reaction time, temperature and pressure. Moreover, the amount of additional phenol was optimized by changing the molar ratio between water and phenol. Phenol was used as capping agent to prevent re-polymerization of active fragment such as formaldehyde. Alkali-lignin was used as a starting material and characterized by a Solid State 13C-NMR, FT-IR and EA (Elemental Analysis). GC-MS analysis confirmed that o-cresol, p-cresol, anisole and 4-hydroxyphathalic acid were the main product and they were quantitatively analyzed by HPLC.

• Food Science and Biotechnology
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• 제16권5호
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• pp.848-853
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• 2007

The effects of high-hydrostatic pressure (HHP) on the ginsenoside concentration in Korean red ginseng were investigated. HHP-pretreated Korean red ginseng samples were compared to samples produced by a conventional method. Six-year-old Korean fresh ginseng (Panax ginseng C.A. Meyer) samples were vacuum-packaged in polyethylene film and treated at room temperature for 1 min with HHP (200-600 MPa) and steamed at $98^{\circ}C$ for 3 hr. Major ginsenosides of red ginseng were analyzed by HPLC. HHP-pretreated red ginseng showed a 45% higher level of total major ginsenosides than conventionally prepared red ginseng. The levels of 4 protopanaxadiol-type ginsenosides increased 34-43% and the levels of 5 protopanaxatriol-type ginsenosides increased 45-66%. Scanning electron microscopy and electrical conductivity spectrum analysis showed that HHP pretreatment damaged ginseng plant cells and increased extraction efficiencies of ginsenosides from red ginseng products.

• 한국대기환경학회지
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• 제11권3호
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• pp.279-290
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• 1995

Recently in Korea, due to the significant drop of lead and bromine levels as a marker of autoemission source in the urban areas, the conventional application of receptor methods has many difficulties to properly apportion mass contribution of some sources. It is then needed to urgently develop alternative source profiles and identify new emission markers. Thus, the study has extensively examined the results obtained from using PAHs and elemental data for receptor modeling and has provided an opportunity to identify alternative source compositions and to determine a proper number of the ambient emission sources in Seoul area. The purpose of the study is to identify the sources of PM-10 and to estimate their mass contributions in Seoul area. Thus, a receptor model, target transformation factor analysis(TTFA) has been massively applied. The TTFA offers the possibility of determining the number of sources and their mass contributions. The input data used in this study are composed of two separate sets: fine (d$_{p}$ < 2.5.mu.m) and coarse (2.5.mu.m < d$_{p}$ < 10.mu.m) mode aerosol samples. Each sample was simultaneously collected by a PM-10 dichotomous sampler during the daytime(8 AM to 8 PM) and the nighttime(8 PM to 8 AM) from February to October 1993 on the Sungdong-Gu, Seoul. All the samples were analyzed to determine the levels of 10 inorganic elements by an XRF system as well as 14 PAHs by a HPLC. However, only 8 inorganic elements and 7 PAHs were used for the various statistical analysis.sis.

• Journal of Ginseng Research
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• 제12권2호
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• pp.164-172
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• 1988

인삼사포닌 정량분석의 상법 purification과정을 역상소형 $C_18$ 컬럼 전처리로 대체할 수 있었으며, 분석시간은 1/4로 단축되었다. 이 방법을 사용하면 total ginsenoside의 회수율은 높으나 protopanaxatriol계 ginsenoside들의 회수율은 약간 낮았으며, 근중 농도 정도의 당류는 ginsenoside 회수율에 영향을 미치지 않았다. Ginsenoside 회수율의 변이계수는 상법의 경우보다 작았으며 이 방법에 사용되는 ginsenoside의 적정량은 10~15mg이었다. 역상소형컬럼방법은 건삼과 홍삼시료처리시에도 상법과 고도의 유의성을 나타냈다. 신속 역상소형컬럼 방법을 실제로 이용하기 위하여 8점의 시료를 동시에 처리하는 소형아크릴 장치를 사용하였다.

• Archives of Pharmacal Research
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• 제26권6호
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• pp.478-481
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• 2003

Phospholipase D is a ubiquitous enzyme that plays an important role in various lipid mediated cellular signaling pathways and produces rare phospholipids, phosphatidylethanol or phosphatidylbutanol, instead of phosphatidic acid with unique catalytic activity transphosphatidylation in the presence of primary alcohols. The reaction products, phosphatidylethanol or phosphatidylbutanol are used as markers of in vitro phospholipase D activity in many studies. For the sensitive detection of the phospholipase D products, we developed an advanced lipid extraction method that facilitates recovery of the compounds. With the new method, the activity change of phosaholipase D by agonists could be detected more easily and the recovery rate was also increased. The increase of detected enzyme activity change was about double fold compared to the conventional lipid extraction method. This method provides selective force for the phospholipase D products in the extraction procedure.

• 한국환경과학회지
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• 제7권2호
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• pp.203-208
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• 1998

A simple on-line measurement system consisting of a conventional peristaltic pump, a HPLC-type heater, and a flow-through spectrophotometer is introduced for the determination of chemical oxygen demand(CODI. The system was configured such that the reaction mixture in the highly concentrated surffuric acrid medium flowing through the PTFE reaction tubing was heated at 150℃ and the absorbance of dichromate was continuously moutored at 445 m. The same addation principle as in the standard procedure was employed akcept the use of CoSO4 as a new effective catalyst. To test the system, potassium hydrogen phthalate was selected as a COD standard material. With suitably optimized reaction condition, the applicable concentration range depends on the concentration of potassium dichromate in the oxidizing reagent. With 2.0×10-3 M and 5.0×10-4M dichromate, the linear dynamic range was observed up to 400 ppm and 100 ppm, respectively. The standards in the Unear ranges were shown to be completely oxidized, which was confirmed with sodium oxalate or Mohr's salt. In all cases, the typical reproduclbility for betweenruns was 2% or less. The proposed measurement system provides the valuable in- formation for the further development of automated analysis system based on the present standard procedure.

• 한국식품영양과학회지
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• 제28권3호
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• pp.586-592
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• 1999

Microwave assisted extraction(MAE) is known as a more environmental friendly process with economic advantages in terms of less time, less solvent, less energy and less wastes than the current time consuming reflux method. It was applied to develop a rapid extraction method for soluble ginseng components that are major materials used for the processing of ginseng products. In a comparative study between pre established MAE(ethanol 60%, power 80 W, process time 4 min$\times$5) and current extraction method(ethanol 80%, temp. 85oC, time 8 hr$\times$5), MAE was more efficient than the current method to obtain an extract yield(soluble solid), but it was insufficient to extract individual ginsenosides, total phenols, reducing components and acidic polysaccharides. MAE with 80% ethanol by 5 times showed, however, that its extraction efficiency on soluble solid, crude saponin, major ginsenosides, and the other components was equal or superior to that of the current method, indicating that ethanol concentration is one of the critical parameters influencing the MAE process. The quality of ginseng extracts from MAE was assured by evaluating the corresponding standards and by comparing TLC and HPLC patterns with the control.