• Mass Spectrometry Letters
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• 제11권1호
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• pp.6-9
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• 2020

Matrix-assisted laser desorption/ionization-mass spectrometry (MALDI-MS) analysis of ionic liquid matrices (ILMs) prepared using pyridine and dihydroxybenzoic acid (DHB), such as 2,3-DHB and 2,5-DHB, displayed an unconventional peak at m/z 232.0, which was regarded as [DHB+pyridine-H]⁺. The peak at m/z 232.0 was not observed from other ILMs prepared using other DHB isomers, such as 2,4-DHB, 2,6-DHB, 3,4-DHB, and 3,5-DHB. Two requirements to observe the peak at m/z 232.0 in a DHB/pyridine ILM are suggested. First, carboxyl and hydroxyl groups must be located ortho to each other. Second, the secondary hydroxyl group must be located at a carbon with a high electron density. Based on these two requirements, a potential mechanism for the generation of the peak at m/z 232.0 is suggested.

• 생약학회지
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• 제35권4호통권139호
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• pp.320-323
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• 2004

Five compounds were isolated from the whole plant of Arabis glabra (Cruciferae) through repeated silica gel and Sephadex LH-20 column chromatography. Their chemical structure were elucidated as salicylic acid, 2,5-dihydroxybenzoic acid, astragalin, rutin, and $quercetin-3,7-O-{\beta}-D-diglucopyranoside$ by spectroscopic analysis.

• Journal of the Korean Wood Science and Technology
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• 제33권6호통권134호
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• pp.71-78
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• 2005

임산바이오매스 자원 이용의 일환으로 율추(栗皺) 열수추출물의 디에틸에테르 가용부 및 초산에틸 가용부로부터 칼럼크로마토그래피 등을 이용하여 3종의 물질을 단리하여 화학구조를 동정한 결과, 3,5-dihydroxybenzoic acid, 3,4,5-trihydroxybenzoic acid 그리고 (+)-catechin을 확인하였다. 이들 단리화합물의 항산화활성을 DPPH 라디칼 전자공여능(EDA)으로 측정한 결과, 10 ppm에서 화합물 3,4,5-trihydroxybenzoic acid (gallic acid)와 (+)-catechin은 대조구인 ascorbic acid와 $\alpha$-tocopherol 보다 높게 나타났고, 특히 화합물 gallic acid는 ascorbic acid보다 약 21배, $\alpha$-tocopherol보다 약 6배 높게 나타났으며 화합물 catechin보다 약 2.7배 높게 나타났다.

• Applied Biological Chemistry
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• 제50권4호
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• pp.358-361
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• 2007

옻나무 목질부를 열수 추출하고, 얻어진 추출물을 $CHCl_3$, EtOAc, H-BuOH 및 $H_2O$로 용매 분획하였다. 이중 EtOAc와 n-BuOH분획으로부터 silica gel, ODS 및 Sephadex LH-20 column chromatography로 정제하여 4개의 화합물을 분리하였다. 각 화합물의 화학구조는 NMR 스펙트럼 데이터를 해석하여, sinapyl aldehyde (1), 2,4-dihydroxybenzaldehyde (2), 2,4-dihydroxybenzoic acid (3) 및 2,4-dihydroxyphenyl-glyoxylic acid (4)으로 동정하였다. 이 화합물들 중 2-4은 옻나무목질부에서 처음 분리된 화합물이다. 이들 화합물 중 sinapyl aldehyde (1)와 2,4-dihydroxyphenylglyoxylic acid (4)의 DPPH radical 소거작용이 $34.7{\pm}0.6%$와 $43.8{\pm}0.9%$로 나타나 합성항산화제인 $BHT(14.4{\pm}0.3%)$보다 높게 나타났다.

• Bulletin of the Korean Chemical Society
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• 제35권5호
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• pp.1409-1412
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• 2014

Sex hormones are important metabolites in vertebrates' development and reproduction. For rapid screening sex hormones, matrix-assisted laser desorption/ionization (MALDI) mass spectrometry (MS) is one of the promising analytical platforms, but MALDI MS faces many challenges in detecting steroids such as low ionization efficiency and matrix background interference. One potential strategy to overcome matrix interference in the low m/z region is using a cyclodextrin (CD)-supported matrix for steroid analysis since CD-supported matrixes are known to effectively suppress matrix-related ion signals. In this study, we aimed to find the optimal CD-supported matrix for the analysis of the nonderivatized sex steroids. Our results showed that the ${\alpha}CD$-supported 2,5-dihydroxybenzoic acid (DHB) matrix efficiently ionized all three major classes of sex hormones, estrogens, androgens, and progestagens, with low or no matrix background and also with high sensitivity. In addition, the ${\alpha}CD$-supported DHB matrix mainly generated molecular ions or protonated ions of sex hormones, and this enabled us to obtain information-rich tandem mass spectra which potentially lead to unambiguous identification of steroid species from complex metabolite mixtures.

• 미생물학회지
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• 제53권2호
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• pp.97-102
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• 2017

포도당과 글루탐산을 함유한 배지에서 시드로포어인 2, 3-dihydroxybenzoic acid (DHB)를 생산하는 Acinetobacter sp. B-W 균주를 글루탐산을 유일한 탄소원과 질소원으로 함유한 배지에 배양한 결과, 상등액에서 2, 3-DHB가 아닌 카테콜 형의 시드로포어를 생산하는 것으로 조사되었다. 글루탐산의 농도는 3%에서 시드로포어 생산이 최고로 나타났으며, 3% 보다 높은 농도에서는 감소하는 것으로 조사되었다. 글루탐산을 유일한 탄소원과 질소원으로 함유한 배지에서 자란 균주 B-W는 배양 온도 $28^{\circ}C$에서는 시드로포어를 생산하지만 $36^{\circ}C$에서는 생산하지 않았다. 또한 $10{\mu}M\;FeCl_3$를첨가한 배지에서는 시드로포어 생산이 완전히 억제되었다. 글루탐산 배지에서 생산된 균주 B-W의 시드로포어는 TLC 전개 용매 butanol: acetic acid: water =12:3:5에서 Rf치가 0.32로 나타나 Rf치가 0.82인 2, 3-DHB와는 다른 것으로 조사되었으며, 또한 항산화 활성도 없는 것으로 나타나 항산화 활성을 가진 2, 3-DHB와는 다른 시드로포어인 것으로 추정되었다.

• 분석과학
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• 제5권1호
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• pp.17-24
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• 1992

Catechol의 유도체인 3, 4-dihydroxybenzoic acid, 3, 4-dihydroxybenzaldehyde, 그리고 adrenaline을 사용하여 게르마늄과 착물을 형성시킨 후 Anodic Stripping Polarography로 정량한 후, 천연물 중의 게르마늄 정량에 적용시켜 분석한 결과 인삼에서 $300{\mu}g/L$, 광천수에서 $210{\mu}g/L$를 검출할 수 있었다.

• Natural Product Sciences
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• 제19권3호
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• pp.201-205
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• 2013

Thirteen phenolic compounds, 1,4-dimethoxybenzene (1), 3,4-dihydroxybenzaldehyde (2), (2E)-3-(4-hydroxy-3,5-dimethoxyphenyl)acrylaldehyde (3), 3,7-dihydroxy-4H-chromen-4-one (4), 2,3-dihydroxy-1-(3,4-dihydroxyphenyl)propan-1-one (5), 4-hydroxy-3-methoxybenzoic acid (6), 4-hydroxy-3,5-dimethoxybenzoic acid (7), methyl 3,4-dihydroxybenzoate (8), 4-hydroxy-3,5-dimethoxybenzaldehyde (9), 3,4-dihydroxybenzoic acid (10), 3-hydroxy-1-(4-hydroxy-3-methoxyphenyl)propan-1-one (11), 2,4,6-trihydroxybenzaldehyde (12) and benzene-1,2,4-triol (13) were isolated from the heartwood of Caesalpinia sappan. Their anti-inflammatory activity was evaluated against LPS-induced NO production in macrophage RAW264.7 cells. Among them, compounds 3 and 8 showed strong inhibitory activities toward the LPS-induced NO production in macrophage RAW264.7 cells with $IC_{50}$ values of 14.5 and 21.5 ${\mu}M$, respectively.

• 분석과학
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• 제8권4호
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• pp.465-468
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• 1995

Matrix assisted laser desorption ionization in mass spectrometry is a fast and accurate method to determine the molecular weight of natural and synthetic polymers. Unknown peptides such as elastase inhibitor and $\small{D}$-hydantoinase were analyzed using sinapinic acid as matrix and their molecular weights were compared with the results from protein sequencer and gel filtration chomatography, respectively. Synthetic polymers such as polyethyleneglycol, polypropyleneglycol, polydimethylsiloxane, and polystyrene were analyzed using matrices such as 2,5-dihydroxybenzoic acid, 4-hdroxyazobenzenecarboxylic acid, and 2-nitrophenyl octyl ether. Average molecular weights of polystyrene were compared with molecular weights by gel permeation chromatography.

• 한국미생물·생명공학회지
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• 제29권3호
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• pp.149-154
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• 2001

버섯유래 저분자 대사산물을 탐색하던 중 대전근교에서 채집한 젖비단 그물버섯(Suillus granulatus)으로 부터 9종의 화합물을 분리하였다. 젖비단 그물버섯을 메탄올로 추출한 후 용매분획하여 그 중 대산산물이 많이 함유된 chloro-form 층 및 ethyl acetate층 에 대하여 각각 silica gel 및 Sephadx LH-20 column chromatography를 수행하였다. 주요대사산물을 함유하고 있는 분획물을 TLC및 분취용 HPLC를 사용하여 정제한 결과 9종의 화합물을 분리하였다. 분리된 화합물의 화학구조를 규명하기 위하여 NMR 및 mass 분석을 수행하여쓰며 그 결과 이들의 화합물은 4-hydro-xyphenylacetic acid, 4-hydroxybenzaldhyde, 2, 5-dihydro-xybenzoic acid methyl ester, 5-deoxy-5 methylthioadeno- sine. indole 3-carboxlic methyl ester indole-3-carbox-aldehyde 1,3,5-trihydroxy 7-methylanthraquinone nicotinamide, 3-geranylgeranyl-4-hydroxybenzoic acid로 동정하였다.