• 생약학회지
• /
• 제17권2호
• /
• pp.161-167
• /
• 1986

The smear method developed by Velaskar and Chitre was modified to allow the screening of plant extracts and/or fractions for platelet anti-aggregating activity. The modified smear method was also found suitable for massive screening of pure compounds. Sample fractions prepared from various plant extracts were examined for their effects against ADP, arachidonic acid (AA) or collagen induced platelet aggregations. Several solvent fractions of plant extracts including water fraction prepared from the methanol extract of Acanthopanax sp. was inhibitory against rat platelet aggregations. The activity guided treatments and fractionations of the water fraction from A. senticosus Max yielded two anti-platelet aggregatory substances, 3, 4-dihydroxybenzoic acid (I) and its artefact ethyl 3, 4-dihydroxybenzoate(II). The inhibitory activities of I and II against rat platelet aggregation were compared with that of aspirin, a known inhibitor of platelet aggregation. Discussions also included the results of the investigations on the structural activity relationships among the various dihydroxybenzoic acid derivatives against platelet aggregations induced by either one of ADP, AA or collagen.

• Natural Product Sciences
• /
• 제6권3호
• /
• pp.117-121
• /
• 2000

The water extract of the aerial parts of Orostachys japonicus A. Berger showed the inhibitory activity against HIV-1 protease. From the same parts of O. Japanicus, 4-hydroxybenzoic acid, 3,4-dihydroxybenzoic acid, gallic acid and methyl gallate, together with flavonoids, kaempferol, quercetin, kaempferol $3-O-{\beta}-D-glucoside$, kaempferol $3-O-{\beta}-D-galactoside$ and quercetin $3-O-{\beta}-D-glucoside$ were isolated and characterized by spectral data.

• Bulletin of the Korean Chemical Society
• /
• 제34권3호
• /
• pp.907-911
• /
• 2013

Numbers of matrix- and analyte-derived ions and their sum in matrix-assisted laser desorption ionization (MALDI) of a peptide were measured using 2,5-dihydroxybenzoic acid (DHB) as matrix. As for MALDI with ${\alpha}$-cyano-4-hydroxy cinnamic acid as matrix, the sum was independent of the peptide concentration in the solid sample, or was the same as that of pure DHB. This suggested that the matrix ion was the primary ion and that the peptide ion was generated by matrix-to-peptide proton transfer. Experimental ionization efficiencies of $10^{-5}-10^{-4}$ for peptides and $10^{-8}-10^{-7}$ for matrices are far smaller than $10^{-3}-10^{-1}$ for peptides and $10^{-5}-10^{-3}$ for matrices speculated by Hillenkamp and Karas. Number of gas-phase ions generated by MALDI was unaffected by laser wavelength or pulse energy. This suggests that the main role of photo-absorption in MALDI is not in generating ions via a multi-photon process but in ablating materials in a solid sample to the gas phase.

• Journal of the Korean Wood Science and Technology
• /
• 제32권2호
• /
• pp.58-64
• /
• 2004

임산바이오매스 자원 이용의 일환으로 율추(栗皺) 열수추출물의 디에틸에테르 가용부의 HPLC 분석결과, 표준물질과의 retention time이 일치한 것을 RI detector로 얻어진 각 피크의 스펙트럼을 표준물질과 비교하고, 순도를 확인하는 방법으로 피크의 동정을 실시하였다. 피크의 동정 결과, phenolic acids와 aldehyde류로는 gallic acid, 3,5-dihydroxybenzoic acid, 2,4,6-trihydroxybenzoic acid, 그리고 protocatechualdehyde이었으며, flavonoids는 catechin과 epicatechin으로 모두 6종이 확인되었다.

• 미생물학회지
• /
• 제52권3호
• /
• pp.254-259
• /
• 2016

시드로포어인 2, 3-dihydroxybenzoic acid (DHB)를 생산하는 Acinetobacter sp. B-W의 플라스미드를 분석한 결과, 20 kb 크기의 플라스미드를 함유하였다. 배양 온도 $43^{\circ}C$ 가 플라스미드가 제거된 돌연변이체 생산에 효과적이었다. 이 돌연변이체는 2,3-DHB 생산 능력을 소실하였으며, chrome azurol S (CAS) 아가 배지에서 시드로포어 생산이 검출되지 않았다. 포도당과 황산 망간을 함유한 배지에서 $28^{\circ}C$로 3일간 배양한 B-W 원 균주와 돌연변이체의 배양 상등액의 pH는 각각 4.5와 8.5로 나타났다. 돌연변이체에서는 ampicillin, actinomycin D, bacitracin, lincomycin과 vancomycin 같은 항생제에 대한 저항성이 사라졌으며, 이러한 항생제에 대한 최소 억제 농도(MIC)가 급격하게 감소하였다. B-W 균주에서 분리한 플라스미드로 대장균을 형질전환시킨 결과, 원 균주와 같은 크기의 플라스미드가 이 형질전환 대장균에서 발견되었다. 플라스미드가 제거된 돌연변이체에서는 플라스미드가 발견되지 않았다. 20 kb 크기의 플라스미드에 2,3-DHB 생산 유전자와 여러 항생제 저항성 유전자가 자리잡고 있는 것으로 추정된다.

• Food Science and Biotechnology
• /
• 제18권2호
• /
• pp.463-470
• /
• 2009

Sixteen antioxidative active compounds isolated from the EtOAc layer of MeOH extracts of kochujang, Korean fermented red pepper paste, were structurally elucidated as fumaric acid, methyl succinate, succinic acid furan-2-yl ester methyl ester (gochujangate, a novel compound), 2-hydroxy-3-phenylpropanoic acid, 3,4-dihydroxybenzoic acid, 2,3-dihydroxybenzoic acid, 2,4-dihydroxybenzoic acid, 6,7-dihydroxy-2H-chromen-2-one (esculetin), caffeic acid, cis-p-coumaric acid, trans-p-coumaric acid, daidzin, genistin, apigenin 7-O-$\beta$-D-apiofuranosyl($1{\rightarrow}2$)-$\beta$-D-glucopyranoside, apigenin 7-O-$\beta$-Dglucopyranoside, and quercetin 3-O-$\alpha$-L-rhamnopyranoside by mass spectrometry (MS) and nuclear magnetic resonance (NMR) experiments. These compounds were analyzed for the first time as antioxidants from kochujang.

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

• Journal of the Korean Wood Science and Technology
• /
• 제33권6호통권134호
• /
• pp.71-78
• /
• 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
• /
• 제50권4호
• /
• pp.358-361
• /
• 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.

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