• 한국식품저장유통학회지
• /
• 제10권4호
• /
• pp.540-546
• /
• 2003

고추잎을 기능성식품의 재료로 이용하기 위한 방안을 모색하기 위하여 각 용매 분획물을 이용하여 생리활성 즉, 전자공여효과, 환원력, 아질산염 소거효과, 항균활성 및 tyrosinase 저해활성에 대하여 조사하였다 추출수율을 조사한 결과 물 분획층에서 16.9%로 가장 높은 추출수율을 나타낸 반면 에틸아세테이트 분획층 0.6%로 가장 낮은 추출수율을 나타내었다. 전자공여효과는 전반적으로 농도가 상승함에 따라 증가하였으며, 환원력도 분획물의 농도가 높아짐에 따라 점차적으로 증가하는 것을 볼 수 있었는데, 특히 ethyl acetate 분획물 0∼600 $\mu\textrm{g}$을 첨가하였을 때는 환원력의 증가가 크게 나타나지 않았으나, 900 $\mu\textrm{g}$이상 첨가구에서는 추출물을 첨가하지 않은 대조구와 비교하여 환원력이 매우 증가하는 것으로 나타났다. 고추잎 분획물을 농도별로 첨가하여 아질산염 소거효과를 측정한 결과 pH가 증가함에 따라 아질산염 소거효과가 감소하는 경향을 나타내었으며, ethyl acetate fraction에서 가장 높은 소거효과를 나타내어 500 $\mu\textrm{g}$을 첨가하였을 때 90%이상의 아질산염 소거효과를 나타내었으며, 농도가 증가함에 따라 아질산염 소거효과도 점차적으로 증가하는 경향을 나타내었다. 고추잎 각 분획물의 항균활성은 ethyl acetate 및 butanol 분획물에서 높게 나타났으며, 각 균주에 대한 clear zone의 직경을 확인한 결과 gram 양성균인 Bacillus cereus에서 20 mm로 항균활성이 가장 높게 나타났고, Staphylococcus aureus 18 mm, Streptecoccus mutans 17 mm순으로 주로 gram 양성균에서 높은 활성을 나타내었다. Tyrosinase 저해활성은 에틸 아세테이트 분획물에서 가장 높은 저해 활성을 나타내었다.

• 대한환경공학회지
• /
• 제22권7호
• /
• pp.1205-1212
• /
• 2000

본 연구는 생물학적 인 방출시 유기물 종류 및 대상슬러지가 acetate에 사전 적응여부에 따른 온도의 영향을 관찰하기 위한 연구이다. 실험에 이용된 슬러지는 축산폐수를 처리하는 연속 회분식 반응조(sequencing batch reactor)로부터 채취하였다. 온도는 인의 방출시 크게 영향을 미치는 인자이며 유기물 종류별로 온도가 $5{\sim}30^{\circ}C$로 증가함에 따라 인 방출속도는 증가함이 관찰되었다. 혐기성 상태에서 주입유기물로 acetate, propionate, glucose 및 도시하수를 이용할 경우 인의 방출시 활성화에너지($E_a$) 값들은 각각 49.83, 55.82, 54.61 및 45.44 KJ/mol이었다. 또한 온도보정계수($\theta$)는 각각 1.0676, 1.0826, 1.0748 및 1.0698이었다. 따라서 인이 방출될 때 온도가 증가함에 따라 반응속도는 크게 증가하지만 활성화에너지 및 온도보정계수를 고려한 유기물 종류별 온도의 영향은 큰 차이가 없었다. 대상슬러지로 사전에 acetate에 적응된 슬러지를 이용할 경우 활성화에너지 값 및 온도보정계수는 각각 44.94 KJ/mol 및 1.0570이었다. 이는 적응되지 않은 슬러지로 부터 얻어진 각각의 값(49.83 KJ/mol 및 1.0676)보다 상대적으로 낮음이 관찰되어 슬러지가 acetate에 서전에 적응된 것이 적응되지 않은 것보다 상대적으로 온도의 영향을 적게 받음을 알 수 있었다.

• Environmental Analysis Health and Toxicology
• /
• 제1권1호
• /
• pp.27-36
• /
• 1986

Experiments were performed on mice to investigate the effect of Panax ginseng petroleum ether fraction on the immunotoxicity of lead acetate. Lead acetate was administered in the drinking water and ginseng p-ether fraction was injected intraperitoneally, Mice were sensitized and challenged with sheep red blood cell. Humoral immune responses were evaluated by antibody production and Arthus reaction. Pathotoxicological influences were measured by serum protein, alkaline phosphatase and total cholesterol. The weight of liver, spleen and thymus were measured. Lead acetate exposure significantly decreased hemagglutination titer, hemolysin titer, Arthus reaction, spleen and thymus weight. Ginseng p-ether fraction administration significantly restored or potentiated reduced humoral immune response, spleen and thymus weight. Reduced serum A/G ratio, total cholesterol and alkaline phosphatase activity were restored or increased by ginseng p-ether fraction administration.

• Macromolecular Research
• /
• 제13권4호
• /
• pp.297-305
• /
• 2005

The compatibilizing effect of maleic anhydride (MA) in the immiscible blends of EVA22 (vinyl acetate content 22%)/ethylene-${\alpha}$-olefin copolymers with 1-butene (EtBC) and 1-octene (EtOC)) comonomers was studied. By adding 1, 2, and 3 phr of MA in the presence of dicumylperoxide, the morphology, tensile strength at break, and 100 and 300 % modulus of EVA22/EtBC and EVA22/EtOC blends were significantly enhanced. The melting point and crystallization point depression were observed upon the addition of MA. The changes in the ${\beta}$ transition and glass transition temperature of ethylene-${\alpha}$-olefin copolymers and ethylene-vinyl acetate copolymers, respectively, indicate that MA plays a role of compatibilizer for these immiscible blends. The TGA thermograms, measured from the blends with MA, show that thermal stability is slightly enhanced with MA, indicating that MA acts as a reinforcing agent either by grafting or crosslinking with other copolymers.

• Bulletin of the Korean Chemical Society
• /
• 제16권3호
• /
• pp.252-256
• /
• 1995

Semiempirical MO calculations using the PM3 method are performed on the reactions of acetate esters with substituted phenolate anions. The mechanistic change from rate-limiting formation to breakdown of the anionic intermediate is shown to occur in the gas-phase, especially for meta-nitrophenyl acetate. However the mechanistic change-over takes place at a lower basicity ($pK_0$) of the anion nucleophile than found for the corresponding formate. This lowering of $pK_0$ has been ascribed to the electron donating effect of the methyl group in the acetate. For the reactions involving rate-limiting breakdown of the intermediate, the large Bronsted coefficients, ${\beta}_X({\beta}_{nuc})$, are expected in general, but the magnitude increases to a larger value and the pK0 is lowered accordingly, when an electron-donating nonleaving group, like $CH_3$, is present. This type of nonleaving group effect provides a necessary condition for the carbonyl addition-elimination mechanism with rate-limiting breakdown of the intermediate.

• 동의생리병리학회지
• /
• 제18권3호
• /
• pp.893-899
• /
• 2004

To test the cytoprotective effect of sophorae radix (SR) against hydrogen peroxide (H₂O₂)-induced cytotoxicity, we investigated the cell viability using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay in the presence of ethyl acetate subfractions of SR water extracts In H9c2 cells. And to clarify the cytoprotective mechanism of SR extracts, we evaluated the cellular glutathione (GSH) contents in the presence of subfraction 1, 2, 3, and 4 of SR ethyl acetate soluble fractions. Among 1 -12 subfractions of SR ethyl acetate soluble fractions, 1, 2, 3 and 4 subfractions have an efficacy inhibiting the cytotoxicity induced by H₂O₂ in H9c2 cells. Also, the protective effects of 1, 2, 3 and 4 subfractions of SR ethyl acetate soluble fractions resulted from the anti-oxidant effects. These results suggest that ethyl acetate soluble fractions of SR water extracts is effective in the prevention of H₂O₂-induced cytotoxicity and 1, 2, 3 and 4 subfraction of ethyl acetate soluble fractions possess the anti-oxidant component.

• Bulletin of the Korean Chemical Society
• /
• 제31권4호
• /
• pp.808-814
• /
• 2010

Activities of nanostructure HZSM-5 and Co-ZSM-5 catalysts (with different Co-loading) for catalytic conversion of ethyl acetate and toluene were studied. The catalysts were prepared by wet impregnation method and were characterized by XRD, BET, SEM, TEM and ICP-AES techniques. Catalytic studies were carried out inside a U-shaped fixed bed reactor under atmospheric pressure and different temperatures. Toluene showed lower reactivity than ethyl acetate for conversion on Co-ZSM-5 catalysts. The effect of Co loading on conversion was prominent at temperatures below $400^{\circ}C$ and $450^{\circ}C$ for ethyl acetate and toluene respectively. In a binary mixture of organic compounds, toluene and ethyl acetate showed an inhibition and promotional behaviors respectively, in which the conversion of toluene was decreased at temperatures above $350^{\circ}C$. Inhibition effect of water vapor was negligible at temperatures above $400^{\circ}C$. An artificial neural networks model was developed to predict the conversion efficiency of ethyl acetate on Co-ZSM-5 catalysts based on experimental data. Predicted results showed a good agreement with experimental results. ANN modeling predicted the order of studied variable effects on ethyl acetate conversion, which was as follows: reaction temperature (50%) > ethyl acetate inlet concentration (25.085%) > content of Co loading (24.915%).

• 도시과학
• /
• 제8권2호
• /
• pp.13-18
• /
• 2019

Using self-made coil dielectric barrier discharge reactor, the removal efficiency of ethyl acetate under simulated experimental parameters such as initial concentration of waste gas, total flow rate, relative humidity and voltage was investigated. The results show that the degradation rate of ethyl acetate increases with the increase of output voltage. When other conditions remain unchanged, the degradation rate decreases with the increase of initial concentration of ethyl acetate; with the increase of total flow rate, the degradation rate of ethyl acetate decreases; with the increase of relative humidity, the degradation rate first increases and then decreases, and when the relative humidity is 64%, the degradation efficiency is the highest.

• 생약학회지
• /
• 제42권3호
• /
• pp.218-222
• /
• 2011

The purpose of this research is to study of inhibitory activity of protostane type triterpens against farnesyl-protein transferase (FPTase). The ingredients of Alismatis Rhizoma, alisol B 23-acetate, C 23-acetate, alisols B and A 24-acetate, and thirteen synthetic analogues from alisol B 23-acetate exhibited inhibition activity against FPTase by scintillation proximity assay method. As a result, alisol C 23-acetate, one of the constituents of Alismatis Rhizoma, the synthetic analogues carboxylated and hydroxylated on branch chain of protostane exhibited a significant inhibitory activity. However, the compounds significantly lowered the inhibitory activity, when there is no 3 position keto on protostane skeletone.

• 생명과학회지
• /
• 제8권5호
• /
• pp.473-478
• /
• 1998

본 연구에서는 된장의 기능성 중에서 대두, 메주, 된장의 발효과정을 거치는 동안 항산화 효과와 아질산염 소거 효과의 변화 추이를 고찰하기 위해 DPPH radical 소거능과 아질산염 소거능을 통한 된장의 활성을 시험하였다. 대두, 메주 및 된장은 methanol extract를 계통 추출법에 의거하여 여러 가지 용매를 사용하여 분획하였으며, 각 분획에 대한 활성실험을 행하였다. MeOH ext.로 본 항산화 효과는 된장〉메주〉대두의 순으로 나타났고, 메주와 대두 간의 효과의 차는 거의 없었다. 아질산염 소거효과는 된장〉대두〉메주의 순을 보였고, 래디칼 소거능보다 아질산염 소거능이 더 효과적으로 나타났다. Ethyl acetate 분획에 있어 항산화 효과가 켰으며, 특히 아질산염의 소거 효과는 L-ascorbic acid의 효과를 상회하였다.이에 된장의 ethyl acetate 분획을 반복 정제하여 genis-tin, daidzein, genistein을 분리하였으며, 이는 된장의 항산화 및 아질산염 소거 효과를 나타내는 활성 물질들은 대두중의 페놀성물질에서 크게 벗어나지 않음을 알 수 있었다.