• 분석과학
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• 제10권5호
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• pp.307-314
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• 1997

지질시료 중의 U과 Th을 유도결합플라즈마 원자방출분광법으로 정량하기 위해 시료를 혼산으로 분해하고 TTA(thenoyltrifluoroacetone)와 TOA (tri-n-octylamine) 추출제를 이용하여 계통적으로 용매추출한 다음 HCl 용액으로 역추출하여 분리하였다. 표준암석 NIST SRM 278에 대한 분석결과는 NIST 및 다른 비파괴분석 결과와 비교하여 양호하였다. 알파선분광법으로 U과 Th의 자연방사성 동위원소를 측정하기 위해 추출분리한 각각을 음이온교환크로마토그래피로 정제하였다.

• 한국식품저장유통학회지
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• 제22권4호
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• pp.553-558
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• 2015

돌산갓에서의 glucosinolates인 sinigrin의 분석법을 확립하기 위해 다양한 용매를 이용하여 추출 후 정성 정량하였다. 돌산갓을 뿌리, 줄기, 잎으로 구분하여 50% $CH_3CN$, 10% $NH_4Cl$, 60% $CH_2OH$, 70% $CH_3OH$ 을 이용해 추출시 50% $CH_3CN$이 가장 sinigrin 함량이 높게 나타났으며 나머지 용매들은 큰 차이가 없었다. 또한 갓 부위별에서 sinigrin함량은 큰 차이가 없었으며 줄기 부위의 50% $CH_3CN$추출물의 sinigrin함량이 728 ppm으로 다소 높게 나타났다. Sinigrin은 농도별로 standard curve를 작성하여 HPLC에 의한 돌산갓 부위별 sinigrin 함량을 정량화 하였고 HPLC로 분석시 UV detector 감도는 242 nm보다 228 nm에서 높게 나타났으며 228 nm에서는 줄기, 뿌리, 잎 순서로 sinigrin함량이 나타났다. 50% $CH_3CN$로 추출한 돌산갓의 chromatogram은 표준물질인 sinigrin의 retention time과 일치하였으며, 잎에서 나타난 peak는 glucosinolates인 glucoraphanin으로 확인되었다. 본 연구의 결과로부터 돌산갓에 함유된 sinigrin 분석을 위한 추출용매는 50% $CH_3CN$, UV detector 파장은 228 nm가 가장 적합하다는 것을 알 수 있었다. 또한, sinigrin의 추출 및 분석이 체계화됨으로써 돌산갓을 이용한 다양한 식품의 저장기간에 따른 sinigrin 함량변화 및 생리기능에 관한 연구에 활용 될 수 있을 것으로 판단된다.

• 한국대기환경학회지
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• 제30권4호
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• pp.362-377
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• 2014

Polycyclic aromatic hydrocarbons (PAHs) have been of particular concern since they are present both in the vapor and particulate phases in ambient air. In this study, a simple method was applied to determine the vapor phase PAHs, and the performance of the new method was evaluated with a conventional method. The simple method was based on adsorption sampling and thermal desorption with GC/MS analysis, which is generally applied to the determination of volatile organic compounds (VOCs) in the air. A combination of Carbotrap (300 mg) and Carbotrap-C (100 mg) sorbents was used as the adsorbent. Target compounds included two rings PAHs such as naphthalene, acenaphthylene, and acenaphthene. Among them, naphthalene was listed as one of the main HAPs together with a number of VOCs in petroleum refining industries in the USA. For comparison purposes, a method based on adsorption sampling and solvent extraction with GC/MS analysis was adopted, which is in principle same as the NIOSH 5515 method. The performance of the adsorption sampling and thermal desorption method was evaluated with respect to repeatabilities, detection limits, linearities, and storage stabilities for target compounds. The analytical repeatabilities of standard samples are all within 20%. Lower detection limits was estimated to be less than 0.1 ppbv. In the results from comparison studies between two methods for real air samples. Although the correlation coefficients were more than 0.9, a systematic difference between the two groups was revealed by the paired t-test (${\alpha}$=0.05). Concentrations of two-rings PAHs determined by adsorption and thermal desorption method consistently higher than those by solvent extraction method. The difference was caused by not only the poor sampling efficiencies of XAD-2 for target PAHs and but also sample losses during the solvent extraction and concentration procedure. This implies that the levels of lower molecular PAHs tend to be underestimated when determined by a conventional PAH method utilizing XAD-2 (and/or PUF) sampling and solvent extraction method. The adsorption sampling and thermal desorption with GC analysis is very simple, rapid, and reliable for lower-molecular weight PAHs. In addition, the method can be used for the measurement of VOCs in the air simultaneously. Therefore, we recommend that the determination of naphthalene, the most volatile PAH, will be better when it is measured by a VOC method instead of a conventional PAH method from a viewpoint of accuracy.

• 한국식품영양학회지
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• 제21권2호
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• pp.143-147
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• 2008

To develop a new anti-wrinkle agent from medicinal plants, this study investigated the optimal conditions for extracting elastase inhibitor from Rheum undulatum L. Maximal extraction occurred by using 70% methanol at $50^{\circ}C$ for 24 hr; the elastase inhibitory activity was 60.4%($IC_{50}:6.7{\times}10^3{\mu}g/m{\ell}$). Systematic solvent extraction, thin layer chromatography, silica gel column chromatography, Sephadex LH-20 column chromatography, and reverse-phase high performance liquid chromatography were used in the partial purification of the elastase inhibitor. The compound was soluble in dimethylsulfoxide, methanol, and ethanol, and had maximum absorption spectra at 231.5 nm and 275.5 nm.

• 한국균학회지
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• 제38권1호
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• pp.57-61
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• 2010

본 연구에서는 버섯으로부터 새로운 항비만 치료(예방) 효과를 갖는 물질을 추출, 정제하여 그 특성을 규명하고, 이를 기능성식품 개발의 소재로 용용하고자 lipase 저해 활성이 높은 상황버섯(Phellinus linteus)의 lipase 저해 물질을 각종 chromatography로 정제 하였다. 먼저 상황버섯(Phellinus linteus) 자실체 추출물에 대한 용매 계통분획을 실시하여 저해 활성이 가장 높은 에틸아세테이트 추출물을 얻었고 이를 3차례의 sillicas gel column chromatography와 분취용 HPLC를 실시하여 $IC_{50}$값이 175 ng의 lipase 저해활성을 가진 연한 연두색 분말의 정제된 lipase 저해 물질을 얻었다. 정제한 lipase 저해물질을 일련의 NMR spectrometry를 실시한 결과 분자량이 523.06 Da으로 추정되었고 225.1 nm에서 최대 흡수 파장을 가진 물질이었다.

• Mycobiology
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• 제38권1호
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• pp.52-57
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• 2010

To develop a potent anti-obesity lipase inhibitor from mushroom, the lipase inhibitory activities of various mushroom extracts were determined. Methanol extracts from Phellinus linteus fruiting body exhibited the highest lipase inhibitory activity (72.8%). The inhibitor was maximally extracted by treatment of a P. linteus fruiting body with 80% methanol at $40^{\circ}C$ for 24 hr. After partial purification by systematic solvent extraction, the inhibitor was stable in the range of $40\sim80^{\circ}C$ and pH 2.0~9.0. In addition to lipase inhibitory activity, the inhibitor showed 59.4% of superoxide dismutase-like activity and 56.3% of acetylcholinesterase inhibitory activity.

• 한국식품영양학회지
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• 제24권3호
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• pp.291-294
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• 2011

A lipase inhibitor from Desmodium oxyphyllum DC. was purified by methanol extraction, systematic solvent extraction, silica gel column chromatography, $C_{18}$ solid phase extraction chromatography and RP-HPLC. We obtained the purified lipase inhibitor with 182 ng($IC_{50}$) of lipase inhibitory activity for a 0.06% yield. Its molecular weight was estimated to be 655.37 Da from an instrumental analysis of MALDI-TOF-MS and it was identified copper-3,5-dibromo-2-hydroxybenzoic acid ($C_{14}H_8Br_4CuO_6$) by $^1H$, $^{13}C$ NMR analysis.

• 한국약용작물학회지
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• 제17권6호
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• pp.434-438
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• 2009

For the development of a new antidementia functional food or alternative drug using agricultural products, Job's tears (Coix lachrymajobi L.), which shows high acetylcholinesterase (AChE) inhibitory activity (55.1%) was selected and the extraction conditions of AChE inhibitor were optimized. AChE inhibitor of Job's tears was maximally extracted when it was treated with 60% methanol at $40^{\circ}C$ for 6 h. The AChE inhibitor of the methanol extracts was partially purified by systematic solvent extraction, thin layer chromatography, silica gel chromatography and reverse-phase HPLC and the partial purified AChE inhibitor with inhibitory activity ($IC_{50}$) of $0.608\;{\mu}g$ was obtained. The partial purified AChE inhibitor was soluble in methanol and hexane, and insoluble in water. Its maximum absorption spectra was 230 nm and also it was stable in the range of $30^{\circ}C$ and $70^{\circ}C$ and pH 4.0-8.0 for 1 h.

• Mycobiology
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• 제36권2호
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• pp.102-105
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• 2008

The acetylcholinesterase (AChE) inhibitor of Yarrowia lipolytica S-3 was maximally produced when it was incubated at $30^{\circ}C$ for 36 h in an optimal medium containing 1% yeast extract, 2% peptone and 2% glucose, with an initial pH 6.0. The final AChE inhibitory activity under these conditions was an $IC_{50}$ value of 64mg/ml. After partial purification of the AChE inhibitor by means of systematic solvent extraction, the final $IC_{50}$ value of the partially purified AChE inhibitor was 0.75 mg/ml. We prepared a test product by using the partially purified AChE inhibitor and then determined its stability for the development of a new antidementia commercial product. The test product was stable at room temperature for 15 weeks.

• Food Science and Biotechnology
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• 제17권3호
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• pp.489-494
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• 2008

In order to develop a potent antidementia $\beta$-secretase inhibitor from phytochemicals, $\beta$-secretase inhibitory activities of extracts from many medicinal plants and herbs were determined. Water extracts from Rubus coreanus showed the highest $\beta$-secretase inhibitory activity of 84.5%. After purification of the $\beta$-secretase inhibitor from R. coreanus using systematic solvent extraction, ultrafiltration, Sephadex G-10 column chromatography, and reverse-phase high performance liquid chromatography (HPLC), a purified $\beta$-secretase inhibitor with $IC_{50}$ inhibitory activity of $6.3{\times}10^3\;ng/mL$ ($1.56{\times}10^{-6}\;M)$ was obtained with a 0.08% solid yield. The molecular mass of the purified $\beta$-secretase inhibitor was estimated to be 576 Da by liquid chromatography-mass spectrometry (LC-MS) and $\beta$-secretase inhibitor also is a new tetrapeptide with the sequence Gly-Trp-Trp-Glu. The purified $\beta$-secretase inhibitory peptide inhibited $\beta$-secretase non-competitively and also show less inhibition on trypsin, however no inhibition on other proteases such as $\alpha$-secretase, chymotrypsin, and elastase.