• Bulletin of the Korean Chemical Society
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• 제31권12호
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• pp.3760-3764
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• 2010

We screened 10,000 heterocyclic small molecules and identified a novel hit core skeleton of 3-(8-chloro-6-(trifluoromethyl) imidazo[1,2-a]pyridine-2-yl)phenyl acetate derivatives. It has been selected as a potential glucagon-like peptide 1 receptor (GLP-1R) activator and demonstrated its effects in increasing GLP-1 secretion, and thereby increasing the glucose responsiveness in both in vitro and pharmacology analyses. Further studies are currently underway to optimize the potency and selectivity of 3-(8-chloro-6-(trifluoromethyl)imidazo[1,2-a]pyridine-2-yl)phenyl acetate derivatives (hit compounds 2 and 8), and address their in vivo efficacy and therapeutic potential. These molecules may serve as useful evidence showing that compounds with a 3-(8-chloro-6-(trifluoromethyl)imidazo[1,2-a]pyridine-2-yl)phenyl acetate moiety are selective GLP-1R agonists, and have potential as anti-diabetic treatment agents.

• Archives of Pharmacal Research
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• 제26권6호
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• pp.463-465
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• 2003

Four protostane-type triterpenes, alisol B 23-acetate (1a), alisol C 23-acetate (2a), alisol B(3a), and alisol A 24-acetate (4a), were isolated from the rhizome of Alismatis plantago-aquatica L. var. orientale Samuelson (Alismataceae) and eleven protostane derivatives (compounds 1-11) were obtained by selective modification from alisol B 23-acetate (1a). These compounds were investigated for their anti-complement activity against the classical pathway of the complement system. Alisol B (3a) and alisol A 24-acetate (4a) exhibited anti-complement activity with $IC_{50} values of 150 and 130 \mu$ M. Among the synthetic derivatives, the tetrahydroxylated protostane triterpene (9) showed moderate inhibitory activity with $IC_{50} value of 97.1 \mu$ M. Introduction of an aldehyde group at C-23 (10; $IC_{50} value, 47.7 \mu$ M) showed the most potent inhibitory effect on the complement system in vitro.

• 한국약용작물학회지
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• 제19권4호
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• pp.238-245
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• 2011

In this study, we investigated antioxidative activity, antibacterial activity against pathogenic strains including methicillin resistant Staphylococcus aureus (MRSA), and tyrosinase inhibitory activity in 75% ethanol extract of Taraxacum coreanum and its fractions. The total polyphenol and flavonoid contents of the extract were 238.59mg/g and 33.18mg/g and the total polyphenol and flavonoid contents of the ethyl acetate fraction were 427.81mg/g and 148.90mg/g as the highest content of fractions. In DPPH radical scavenging ability, $SC_{50}$ values of the ethyl acetate and butanol fraction were 38.40${\mu}g/ml$ and 82.28 ${\mu}g/ml$, respectively. In antibacterial activity by the disc diffusion assay against S. aureus, S. epidermidis and MRSA, the ethyl acetate fraction showed stronger antibacterial activity than other fractions and the extract. Especially, the ethyl acetate fraction was exhibited effective antibacterial activity against MRSA. In the cytotoxicity measurement by MTT assay, the extract and fractions were exhibited Raw 264.7 cell viabilities of 96.32~143.21% as nontoxic result in concentration of 5~100 ${\mu}g/ml$. As a result, the ethyl acetate fraction of the 75% ethanol extract from T. coreanum could be applicable to functional materials for related fields.

• Journal of Microbiology
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• 제45권4호
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• pp.311-317
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• 2007

In this study, the effects of phosphate concentration and carbon source on the patterns of alkaline phosphatase (APase) and phospholipase (PLase) expression in Vibrio vulnificus ATCC 29307 were assessed under various conditions. The activities of these enzymes were repressed by excess phosphate (4 mM) in the culture medium, but this repression was reversed upon the onset of phosphate starvation in low phosphate defined medium (LPDM) containing 0.2 mM of phosphate at approximately the end of the exponential growth phase. The expressions of the two enzymes were also influenced by different carbon sources, including glucose, fructose, maltose, glycerol, and sodium acetate at different levels. The APase activity was derepressed most profoundly in LPDM containing fructose as a sole carbon source. However, the repression/derepression of the enzyme by phosphate was not observed in media containing glycerol or sodium acetate. In LPDM-glycerol or sodium acetate, the growth rate was quite low. The highest levels of PLase activity were detected in LPDM-sodium acetate, followed by LPDM-fructose. PLase was not fully repressed by high phosphate concentrations when sodium acetate was utilized as the sole carbon source. These results showed that multiple regulatory systems, including the phosphate regulon, may perform a function in the expression of both or either APase and PLC, in the broader context of the survival of V. vulnificus.

• Journal of Pharmaceutical Investigation
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• 제29권3호
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• pp.171-177
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• 1999

Lidocaine(2-Diethylaminoaceto-2', 6'-xylidide) was transdennally delivered by iontophoresis and the effect of enhancer on the delivery of lidocaine was studied. We delivered lidocaine through the skin of hairless mouse using diffusion cell and investigated the effect of the amount of cation salts such as sodium chloride, calcium acetate, zinc acetate and aluminum acetate on the drug delivery. The amounts of transported drugs and adsorbed metal ions were measured by HPLC(High Perfonnance Liquid Chromatography) and AAS(Atomic Absorption Spectrophotometry), respectively. The addition of zinc acetate and aluminum acetate greatly enhanced the delivery of lidocaine. The detection of two metal ions by AAS seemed to support the idea that the astringency effect of these ions were the main reason for the enhancement of transdermal delivery.

• 생약학회지
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• 제50권2호
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• pp.96-101
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• 2019

Methanol extract of Helianthus tuberosus L. (Compositae) flower was investigated to research the anti-oxidative activity by using a Caenorhabditis elegans model system. Ethyl acetate soluble fraction of the methanol extract showed the most potent DPPH radical scavenging activity. The ethyl acetate fraction was measured on its activities of superoxide dismutase (SOD), catalase, and oxidative stress tolerance with reactive oxygen species (ROS) level in C. elegans. Furthermore, in order to verify if regulation of stress-response gene is responsible for the increased stress tolerance of C. elegans which treated by the ethyl acetate fraction, we checked SOD-3 expression using a transgenic strain. Consequently, the ethyl acetate fraction of H. tuberosus flower increased the catalase and SOD activities in a dose-dependent manner in C. elegans, reduced ROS accumulation dose-dependently. Besides, the ethyl acetate fraction-treated CF1553 worms showed higher SOD-3::GFP intensity than the control group.

• 생약학회지
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• 제49권4호
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• pp.322-327
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• 2018

Methanol extract of Salvia miltiorrhiza Bunge (Labiatae) root was investigated to research the anti-oxidative activity, by using a Caenorhabditis elegans model system. The methanol extract of this plant showed significant DPPH radical scavenging and superoxide quenching activities. Ethyl acetate soluble fraction of the methanol extract that showed the most potent DPPH radical scavenging and superoxide quenching activities. The ethyl acetate fraction was tested on its activities of superoxide dismutase (SOD), catalase, and oxidative stress tolerance in C. elegans. Furthermore, in order to see if regulation of stress-response genes is responsible for the increased stress tolerance of the ethyl acetate fraction treated C. elegans, we checked SOD-3 expression using a transgenic strain. Consequently, the ethyl acetate fraction of S. miltiorrhiza root increased the catalase and SOD activities in a dose-dependent manner in C. elegans. Besides, the ethyl acetate fraction-treated CF1553 worms showed higher SOD-3::GFP intensity than the non-treated ones.

• 한국응용과학기술학회지
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• 제35권4호
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• pp.1269-1275
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• 2018

Raphiolepis indica (R. indica) is one of evergreen shrubs belonging to the Rosaceae and is grown wildly in Jeju. This study was performed to evaluate the hepatoprotective effect of different fractions (n-hexane, dichloromethane, ethyl acetate, butanol, water) from R. indica. Anti-oxidative effects were determined using 1,1-diphenyl-2-picrylhydrazyl (DPPH) scavenging activity and total phenol contents. Hepatoprotective effect was identified by 3-[4, 5-dimethylthiazol-2-yl]-2, 5-diphenyltetrazolium bromide (MTT) assay in Huh7 cells. Among various fractions, ethyl acetate and butanol fractions showed the lowest DPPH remained rate reaching approximately 78.7 and 65.5% at $400{\mu}g/mL$. Ethyl acetate and butanol fractions showed the total phenolic content at 164.5 and 137.3 mg GAE/g extract. The ethyl acetate and butanol fractions were resistant against oxidative stress in MTT assay and showed higher hepatoprotective effect than other fractions. Therefore, these results suggest that the ethyl acetate and butanol fractions of R. indica might have therapeutic value in liver damage.

• 한국식품영양학회지
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• 제35권4호
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• pp.276-281
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• 2022

Antioxidant activities and α-glucosidase inhibitory activities of Taraxacum officinale solvent fractions were measured. Extraction yields (relative to raw material) of 50% ethanol, hexane, ethyl acetate, butanol, and water were found to be 10.29, 2.61, 5.54, 2.15, and 0.96%, respectively. Polyphenol and flavonoid contents were high in ethyl acetate extract of Taraxacum officinale at 56.88 mg gallic acid/g and 33.27 mg gallic acid/g, respectively. DPPH, hydroxyl radical scavenging activity, and SOD-like activity measurement (IC₅₀%) of Taraxacum officinale 50% ethanol extract, hexane, butanol, ethyl acetate, and water fractions were 22.64, 18.65, 10.29, 20.81, 20.46 mg/mL, 24.68, 10.69, respectively. It was found to be 9.66, 15.81, 13.77 mg/mL, 32.84, 17.09, 12.73, 33.63, and 33.91 mg/mL, and was high in the ethyl acetate layer. Results showed that α-glucosidase inhibitory activities of Taraxacum officinale solvent fraction were 25.75, 15.93, 35.87, 15.96, and 2.88% for 50% ethanol extract, hexane, butanol, ethyl acetate, and water fractions, respectively.

• 한국식품영양과학회지
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• 제41권9호
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• pp.1197-1204
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• 2012

본 연구는 참취 에탄올 추출물과 용매분획물의 항산화 활성과 총 폴리페놀 함량 및 총 플라보노이드 함량을 측정하고, 생리활성과 항산화 성분 간의 상관관계를 비교 분석하였다. 총 폴리페놀 함량은 70% 에탄올 추출물 99.6 mg GAE eq/g으로 나타났으며, ethyl acetate 분획물 141.9 mg GAE eq/g으로 다른 분획물보다 높은 함량을 나타내었다(p<0.05). 또한 총 플라보노이드 함량도 ethyl acetate 분획물에서 105.6 mg QUE eq/g으로 높은 함량을 나타내었다(p<0.05). DPPH 라디칼 소거능과 ABTS 라디칼 소거능의 경우 ethyl acetate 분획물 1,000 ${\mu}g/mL$ 농도에서 97.1% 및 98.7%를 보여 대조군인 ascorbic acid, ${\alpha}$-tocopherol 및 BHT와 유사한 소거능을 나타내었다(p<0.05). SOD 유사활성은 ethyl acetate 분획물 1,000 ${\mu}g/mL$ 농도에서 42.8%의 활성을 나타내어 DPPH, ABTS 라디칼 소거능보다 비교적 낮은 활성을 나타내었다(p<0.05). FRAP에 의한 환원력 측정 결과에서도 ethyl acetate 분획물에서 높은 활성을 나타내었다(p<0.05). 그러나 $Fe^{2+}$ chelating 활성 측정은 chloroform 분획물 1,000 ${\mu}g/mL$ 농도에서 81.8%로 높게 나타났으며, 오히려 ethyl acetate 분획물에서는 6.2%로 가장 낮게 나타났다(p<0.05). 이상의 결과 참취 70% 에탄올 추출물과 용매 분획물 중 ethyl acetate 분획물이 다량의 폴리페놀과 플라보노이드를 함유하고 있으며, 항산화 효과가 높게 나타났다. 따라서 참취는 천연 항산화 소재 및 기능성식품으로의 활용 가능한 약용 식물자원인 것으로 판단된다.