• 한국환경과학회지
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• 제23권6호
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• pp.1151-1156
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• 2014

The photocatalytic decomposition characteristics of single n-pentane, n-pentane mixed with methyl ethyl ketone (MEK), and n-pentane mixed with ethyl acetate (EA) by cylindrical UV reactor installed with $TiO_2$-coated perforated plane were studied. The effects of the residence time, the inlet gas concentration, and the oxygen concentration were investigated. The removal efficiency of n-pentane was increased with increasing the residence time and the oxygen concentration, but decreased with increasing the inlet concentration of n-pentane. The photocatalytic decomposition rates of single n-pentane, n-pentane mixed with MEK, and n-pentane mixed with EA fitted well on Langmuir-Hinshelwood kinetics equation. The maximum elimination capacities of single n-pentane, n-pentane mixed with MEK, and n-pentane mixed with EA were obtained to be $465g/m^3{\cdot}day$, $217g/m^3{\cdot}day$, and $320g/m^3{\cdot}day$, respectively. The presence of coexisting MEK and EA vapor had a negative effect on the photocatalytic decomposition of n-pentane and the negative effect of MEK was higher than that of EA.

• 생약학회지
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• 제45권3호
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• pp.220-226
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• 2014

Diospyros lotus has been cultivated for its edible fruits and leaves which are considered for its medicinal importance. The aim of this study was to evaluate the anti-melanogenesis of ethyl acetate (EA) fractions from D. lotus leaves in B16 cells. The order of the total polyphenol content with regard to the different solvent fractions from D. lotus leaves was EA>butanol>metahanol>chloroform>n-hexane. The major compounds of EA fraction from D. lotus leaves by HPLC analysis were myricitrin and myricetin. Cellular TYR activity and melanin content in response to treatment with 100 mg/mL of EA fraction was inhibited more strongly than group treated with arbutin. Further, EA fraction exhibited significant anti-melanogenesis effects by reducing the levels of microphthalima-associated transcription factor (MITE), inhibiting the synthesis of TYR, tyrosinase-related protein-1 (TRP-1) and TRP-2. Therefore, EA fractions from D. lotus leaves may be a good source of skin-whitening agents in the future development of medicine-based trouble skin therapy.

• 대한의생명과학회지
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• 제6권3호
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• pp.181-186
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• 2000

항암제로 사용되어 온 아위를 사용하여 극성에 따른 용매추출 분획을 얻고 TPA로 처리된 HL-60 세포를 사용하여 기질부착 억제실험을 수행한 결과, ethyl acetate (EA) 층에서 가장 강한 부착억제효과가 있음을 알아 내었기에 ethyl acetate (EA)층을 다시 ethyl acetate (EA), hexane (HEX), ethyl ether (EE)로 추출한 뒤 3회 chromatography하여 아위 순수활성물질인 asadisulphide를 분리해 내었다. 이 순수활성물질을 가지고 HL-60 암세포에 대한 부착 억제실험을 수행한 결과 asadisulphide는 최소농도 2 $\mu\textrm{g}$/ml에서 HL-60 세포의 부착을 98%억제하였다. 또한 assdisulphide는 HL-60 세포에 대해 ED$_{50}$값은 2.6 $\mu\textrm{g}$/ml이었으며, 20 $\mu\textrm{g}$/ml 농도 이하에서 세포독성이 없고 항암효과가 있다는 사실을 규명하였다.

• 생약학회지
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• 제54권2호
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• pp.66-71
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• 2023

Ethyl acetate (EA) soluble fraction of the Berberis amurensis (Berberidaceae) methanol extract showed the potent DPPH radical scavenging activity through Caenorhabditis elegans model system. The EA fraction was measured for the activity of superoxide dismutase (SOD), catalase, and oxidative stress tolerance by using C. elegans along with reactive oxygen species (ROS) level. In addition, SOD-3 expression was conducted using a transgenic strain (CF1553) to confirm that the regulation of the stress response gene is responsible for the increased stress tolerance of C. elegans treated by the EA fraction. As a result, the EA soluble fraction of B. amurensis increased SOD and catalase activity, and decreased ROS accumulation in a dose-dependent manner. Furthermore, the EA fraction-treated CF1553 worm showed higher SOD-3::GFP intensity than the control worm.

• 대한화장품학회지
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• 제50권1호
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• pp.85-93
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• 2024

본 연구에서는 산해박(Cynanchum paniculatum)을 이용하여 에틸아세테이트로 분획물을 제조하고, 지표물질 페오놀(paeonol)의 구조와 함량을 확인하였다. 산해박은 n-hexane, methylene chloride, ethyl acetate, n-butanol, distilled water를 사용해서 순차적 용매 분획을 시행하여 분획물을 획득하였고, 에틸아세테이트(EtOAc)에서 가장 높은 paeonol 함량을 보였다. 산해박 에틸아세테이트 분획물(EA)의 구조는 nuclear magnetic resonance (NMR)을 통해서 확인하였고, 함량은 high performance liquid chromatography (HPLC) 분석을 통해 확인하였다. 산해박 에틸아세테이트 분획물(EA)의 항산화 활성 효과를 검증하기 위해 2,2'-azino-bis(3-ethylbenzothiazoline6-sulphonic acid) (ABTS) 소거능을 통해서 확인하였으며, 염증 완화 효과를 검증하기 위해 lipopolysaccharide (LPS)로 염증반응을 유도시킨 RAW 264.7 세포에서 nitric oxide (NO) 생성 억제능을 확인한 결과, 농도 의존적으로 NO 생성을 저해함을 확인하였다. 추가적으로, ultraviolet B (UVB)에 의해 유도된 MMP-1 생성량은 산해박 에틸아세테이트 분획물(EA)의 농도 의존적으로 감소하였고, 프로콜라겐(procollagen type-I) 생성 능력은 농도 의존적으로 증가하는 것을 확인하였다. 또한 산해박 에틸아세테이트 분획물(EA)을 함유한 화장품 제형을 이용하여 임상시험을 실시한 결과, 눈가 주름 개선 효과를 확인하였다. 이를 통하여 산해박은 항산화 및 항노화 효과를 가지는 천연 기능성 화장품 소재로 사용이 가능할 것으로 기대된다.

• Journal of Ginseng Research
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• 제35권4호
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• pp.442-448
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• 2011

We previously reported that in vitro anti-platelet activity of tissue-cultured mountain ginseng (TCMG) ethanol extracts show improved efficacy when compared with commercial ginseng products such as Korean red ginseng and Panax ginseng. However, information on the anti-platelet activity of the ethyl acetate fraction from TCMG adventitious roots is limited. Therefore, in this study, we further investigated the effects of an ethyl acetate extract of TCMG (EA-TCMG) adventitious roots on in vitro antiplatelet activity in whole human blood and its effect on peripheral blood flow in mice. We found that EA-TCMG inhibited platelet aggregation with $IC_{50}$ values of 271, 180, and 147 ${\mu}g$/mL induced by collagen, adenosine-5'-diphosphate, and arachidonic acid, respectively. Among the three agonists used, thromboxane $A_2$ formation induced by arachidonic acid was markedly suppressed. Furthermore, EA-TCMG improved the peripheral circulatory disturbance by improving vascular blood flow. In conclusion, these results suggest that ethyl acetate extracts from TCMG adventitious roots might inhibit vascular platelet aggregation and thrombus formation.

• 한국응용과학기술학회지
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• 제27권2호
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• pp.216-221
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• 2010

Polyvinyl acetate (PVAc) prepared by emulsion polymerization has broad applications for additive such as paint binder, adhesive for wood and paper due to its low glass transition temperature which help to plasticize substrate resins. Since emulsion polymerization has a disadvantage that surfactant and ionic initiator degrade properties of the product polymer, poly (vinyl acetate-eo-ethyl acrylate) (VAc-EA) was synthesized using potassium persulfate as catalyst and polyvinylalcohol (PVA) as protective colloid to prevent the degradation. The copolymer latex product was internally plasticized and has enhanced adhesion, water resistance during VAc-EA emulsion polymerization. No coagulation and complete conversion occur with the reactant mixture of 10 mmol/L potassium persulfate, 10 mmol/L poly ( vinyl alcohol) (PVA 17). As the concentrations of PVA increase, the viscosity becomes increase.

• Preventive Nutrition and Food Science
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• 제16권3호
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• pp.217-223
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• 2011

Ischemic stroke constitutes about 80% of all stroke incidences. It is characterized by brain cell death in a region where cerebral arteries supplying blood are occluded. Under these ischemic conditions, apoptosis is responsible for the cell death, at least in part. Goat's-beard (Aruncus dioicus var. kamtschaticus) is a perennial plant that grows naturally in the alpine regions of Korea. In the present study, we first determined whether water extract of goat's-beard (HY1646) and some of its fractions prepared by partitioning with organic solvents could improve the viability of human hepatocellular carcinoma cells (HepG2) cultured under hypoxic condition by blocking apoptotic pathways. Based on the in vitro findings, we subsequently investigated whether HY1646 and the ethyl acetate fraction (EA) selected from cell culture-based screening could attenuate brain injury in a rat middle cerebral artery occlusion (MCAO) model of ischemia (2 hr), followed by 22 hours of reperfusion. The cell number was sustained close to that initially plated in the presence of HY1646 even after 24 hr of cell culture under hypoxic condition (3% $O_2$), at which time the cell number reached almost zero in the absence of HY1646. This improvement in cell viability was attributed to the delay in apoptosis, identified by the formation of DNA ladder in gel electrophoresis. Of fractions soluble in hexane, ethyl acetate (EA) and butanol, EA was chosen for the animal experiments because EA demonstrated the best cell viability at the lowest concentration (10 ${\mu}g$/mL). HY1646 (200 mg/kg) and EA (10 and 20 mg/kg) significantly reduced infarct size, an index of brain injury, by 16.6, 40.0 and 61.0%, respectively, as assessed by 2,3,5-triphenyl tetrazolium chloride staining. The findings suggest that prophylactic intake of goat's beard might be beneficial for preventing ischemic stroke.

• 한국식품영양과학회지
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• 제43권11호
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• pp.1635-1641
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• 2014

본 연구는 고욤잎 유래 EA 분획물의 항산화 및 항가려움 활성을 조사하였다. EA 분획물은 DPPH 라디칼 소거 활성이 수용성 및 MeOH 추출물보다 매우 우수하였을 뿐만 아니라 합성 항산화제인 BHT보다 현저히 높았다. 또한 ABTS 라디칼 소거 활성도 수용성과 MeOH 추출물뿐만 아니라 Trolox보다 현저히 높았다. 본 연구에 사용된 EA 분획물과 수용성 및 MeOH 추출물은 세포에 대한 독성이 없었다. 또한 EA 분획물은 농도에 의존적으로 활성화된 비만세포로부터 히스타민 방출 억제와 TNF-${\alpha}$ 생성 억제 효과가 있었으며, 같은 농도에서 수용성 및 MeOH 추출물보다 억제 효과가 우수하였다. 더욱이 EA 분획물은 농도 의존적으로 compound 48/80으로 유도된 가려움증을 효과적으로 억제하는 활성이 있었고, 같은 농도에서 항가려움 약제로 알려진 azelastine보다는 그 효과가 낮았지만 수용성 및 MeOH 추출물뿐만 아니라 methysergide보다 우수한 항가려움 효과를 발휘하였다. 앞으로 이러한 항가려움 효과에 대한 EA분획물의 분자적 작용기전을 규명해야 할 필요가 있으며, 고욤잎 유래 EA 분획물은 강력한 항산화 및 항가려움 활성을 지닌 우수한 소재라 사료된다.

• 한국식품과학회지
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• 제50권2호
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• pp.209-215
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• 2018

치자 추출물의 극성에 따른 분획-헥세인, 에틸아세테이트와 뷰탄올 분획의 폴리페놀 함량을 평가한 결과, 에틸아세테이트 분획이 다량의 폴리페놀을 함유함을 하였고, DPPH와 ABTS 라디칼 제거와 환원력 실험에서 강력한 라디칼 제거와 환원능력을 나타냈다. 또한 치차 에틸아세테이트 분획(GJ-EA)의 라디칼 제거 활성을 세포수준에서 평가한 결과, LPS로 활성화된 BV-2 미세아교세포에서 발생하는 과량의 산화질소 생성을 억제하였고, 과산화수소를 처리한 췌장암 세포주의 증식과 이동성에 대해 억제효과를 나타내었다. 따라서 치자 에틸아세테이트 분획(GJ-EA)이 라디칼 제거효과, 과산화수소 유도형 암세포의 증식과 이동성에 대한 억제효과를 가진다는 것을 확인하여 치자 에틸아세테이트 분획(GJ-EA)을 이용한 기능성 식품소재 개발을 위한 기초자료로 활용될 수 있음을 제시하였다.