• Journal of the East Asian Society of Dietary Life
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• v.21 no.5
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• pp.713-722
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• 2011

This study was conducted to monitor the quality characteristics of Acai (Euterpe oleracea Mart.) ethanolic extracts by a response surface methodology. The independent variables in the extraction experiments were ethanol concentration (0~100%), extraction temperature ($35{\sim}95^{\circ}C$), and ratio of solvent to sample (10~30 mL/g). The coefficients of determinations ($R^2$) were 0.9596 (p<0.01), 0.9356 (p<0.01), and 0.8842 (p<0.05) for total polyphenol, total flavonoid, and electron donating ability, respectively. The electron donating ability and nitrite scavenging effect improved with an increase in ethanol concentration as opposed to extraction temperature. Anthocyanin content with extraction conditions was 74.421~291.841 mg/L and the coefficient of determinations ($R^2$) was 0.9792 (p<0.01). ORAC (oxygen radical absorbance capacity) with extraction conditions was 137.73~562.94 ${\mu}moles$ TE/g and increased with an increase in ethanol concentration and a decrease in the ratio of solvent to sample content. Estimated conditions for maximum extraction including yield, total polyphenol, total flavonoid, electron donating ability, anthocyanin content, and ORAC were 28~58% for ethanol concentration, $60{\sim}68^{\circ}C$ for extraction temperature, and 10~12 mL/g for ratio of solvent to sample.

• Journal of the Korea Institute of Military Science and Technology
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• v.23 no.5
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• pp.523-531
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• 2020

Extraction and anti-solvent crystallization were proposed to recover octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) from pressed polymer bonded explosives(PBXs). DXC-57 and DXC-59, whose polymeric binders are Estane and HyTemp with dioctyl adipate plasticizer, respectively, were used as pressed PBX models. Estane of DXC-57 was removed by washing with tetrahydrofuran prior to extraction, which enabled the crystallization of HMX at a low degree of supersaturation, sufficient to obtain β-form HMX. Using dimethyl sulfoxide and ethanol as the extraction solvent and the anti-solvent for crystallization, respectively, HyTemp and dioctyl adipate in DXC-59 were separated from HMX. The purity of recovered β-form HMX was higher than 99 %.

• Korean Journal of Oriental Medicine
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• v.18 no.3
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• pp.147-154
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• 2012

Objectives : This study was performed to find best extraction solvent for application of Ulmi cortex to food or herbal medicine as an antioxidant only using water, ethanol and their mixtures. Methods : The Ulmi cortex extracts were prepared using water and 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90% and 100% (v/v) ethanol, and were evaluated yields, total polyphenol contents, DPPH and ABTS radical scavenging activities, lipid peroxidation activities, and catechin and epicatechin contents. Results : Among the Ulmi cortex extracts, the yield was highest in water extract (8.9%) and lowest in ethanol extract (3.8%). The yield of 30% ethanol extract (8.5%) also was very high to similar with water extract. The total polyphenol content was highest in the 30% ethanol extract ($253.6{\mu}g/mg$ extract) and lowest in water extract ($109.0{\mu}g/mg$ extract). The DPPH radical scavenging activity was highest in ethanol extract (IC50, $8.53{\mu}g/ml$), ABTS radical scavenging activity was highest in 60% ethanol extract (IC50, $3.08{\mu}g/ml$), and the inhibition of lipid peroxidation was highest in 70% ethanol extract (IC50, $7.96{\mu}g/ml$). As ethanol content of extraction solvent increased from 0% to 30%, the antioxidant activities were remarkably increased whereas from 30% to 100%, the antioxidant activities were increased or decreased a little. Conclusions : The findings of the present study suggest that 30% ethanol is best solvent for extraction of Ulmi cortex, considering yield, polyphenol content, and antioxidant activities with extraction cost.

• Journal of Environmental Health Sciences
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• v.24 no.2
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• pp.74-79
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• 1998

This study was conducted to evaluate the surfactant solutions which influence solvent extraction from light hydrocarbon contaminated soils. Nine characteristic compounds were studied: benzene, toluene, ethylbenzene, o-xylene, mxylene, p-xylene, n-propylbenzene, 1,2,4-trimethylbenzene, and n-butylbenzene which were found in gasoline. Adsee-799 and Witbreak DRA-22 showed some extractive capacity for light hydrocarbons from soil. There was no added advantage obtained by using other surfactants in this study. No removal of contaminants from soil was observed when the surfactant concentration was 0.5 percent or below. When the surfactant concentration was 4 percent, the average recovery for some hydrocarbons was 10.8 percent, which was the best obtained at these levels. There was 10 percent surfactant contribution for methanol extraction from soil with the Witbreak DPG-482 and Witbreak DRA-22. This study provided a useful screening technique for procedures that can be used to remediate soils contaminated with light hydrocarbons.

• Bulletin of the Korean Chemical Society
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• v.32 no.3
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• pp.829-835
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• 2011

A dispersive liquid-liquid microextraction based on solidification of floating organic droplet (DLLME-SFO) has been developed as a new approach for the extraction of trace copper in water and beverage samples followed by the determination with flame atomic absorption spectrometry. In the DLLME-SFO, 8-hydroxy quinoline, 1-dodecanol, and methanol were used as chelating agent, extraction solvent and dispersive solvent, respectively. The experimental parameters related to the DLLME-SFO such as the type and volume of the extraction and dispersive solvent, extraction time, sample volume, the concentration of chelating agent and salt addition were investigated and optimized. Under the optimum conditions, the enrichment factor for copper was 122. The method was linear in the range from 0.5 to $300\;ng\;mL^{-1}$ of copper in the samples with a correlation coefficient (r) of 0.9996 and a limit of detection of $0.1\;ng\;mL^{-1}$. The method was applied to the determination of copper in water and beverage samples. The recoveries for the spiked water and beverage samples at the copper concentration levels of 5.0 and $10.0\;ng\;mL^{-1}$ were in the range between 92.0% and 108.0%. The relative standard deviations (RSD) varied from 3.0% to 5.6%.

• Applied Chemistry for Engineering
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• v.35 no.5
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• pp.468-472
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• 2024

This study experimentally examined the separation performance of indole (IN) contained in crude methyl naphthalene oil (CMNO) by methanol extraction and then compared these results with formamide extraction. CMNO containing about 4.36% IN, which is attracting attention as an intermediate raw material such as medicine, essential amino acids, and perfumes, was used as a raw material, and methanol aqueous solution was used as a solvent, respectively. The increase in the initial volume fraction of water in the solvent (y_w,0) sharply decreased the distribution coefficient (m_IN) and yield (Y_IN) of IN, but conversely increased the selectivity of IN in reference to 2-methylnaphthalene (2MNA). An increase in the initial volume ratio of solvent to feed (E₀/R₀) increased m_IN, Y_IN, and 𝛽_IN,2MNA. In the range of 0.1 ≤ y_w,0 ≤ 0.3, m_IN and Y_IN of methanol extraction were approximately 1.9~5.9 times and 1.8~3.6 times greater than those of formamide extraction, respectively, whereas 𝛽_IN,2MNA of formamide extraction were 4.6~8.2 times greater than those of methanol extraction.

• Food Science and Preservation
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• v.13 no.2
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• pp.216-222
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• 2006

Microwave energy (2450 MHz) was applied to extract health-effective component (HEC) from grape seed. Three different solvents approved for grape seed extract such as water, ethanol and acetone, were confirmed in their microwave-heating properties and by which extraction efficiencies were determined. Microwave-assisted extraction (MAE) was performed under different parameters; microwave power : (0, 50, 100 and 150), time : (1, 3, 5, 7, and 9 min), the sample to solvent ratio : (1:20, 1:10, 1:5 and 1:2.5), and particle size(whole, 20, 40 and 60 mesh) and the subsequent extracts were used for determining their physicochemical properties, such as total yield : (TY), total phenolics : (TP), catechin content : (CC), electron donating ability : (EDA), and browning color. The heating properties of solvent demonstrated the optimal ranges of microwave and time as 100 W and 2 to 6 min. The TY and HFC content were higher with increasing powers in water and ethanol solvent, while HFC content were lower in acetone at over 100 W. The longer of extraction time up to 5 min, the higher extraction efficiency. Based upon the overall MAE efficiency and solvent recovery, it was found optimal to use 10 times volume of ethanol for 10 mesh of seed particle at 100 W.

• Korean Journal of Medicinal Crop Science
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• v.24 no.5
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• pp.375-385
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• 2016

Background: The study was conducted to elucidate the extraction conditions under which white ginseng has cognition-improving efficacy. Methods and Results: Extracts from white ginseng under different solvent and temperature conditions were analyzed for ginsenoside content and inhibitory effect on N-methyl-D-aspartate (NMDA) receptor and acetylcholinesterase. The total ginsenoside contents and amounts of ginsenoside Rb1 plus ginsenoside Rg1 from the 1st extracts (prepared with EtOH/$H_2O$ as solvent) were higher than those from the 2nd extracts (extracted with $H_2O$ after the 1st EtOH/$H_2O$ extraction). The contents in the 1st and 2nd extracts produced at $80^{\circ}C$ were also higher than those obtained at $50^{\circ}C$. Samples from the 1st extraction at $80^{\circ}C$ indicated higher inhibitory activities on NMDA receptors-whose excessive activation is thought to mediate the calcium-dependent neurotoxicity associated with several neurodegenerative diseases-than those from the 2nd extraction. Among the samples prepared at varying temperatures, the extract prepared at $50^{\circ}C$ showed the highest suppression activity on NMDA receptors. Note, however, that the extracts from the 2nd extraction at $50^{\circ}C$ inhibited acetylcholinesterase-whose inhibition could be a therapeutic strategy for neurodegenerative diseases with cognitive deficits and memory malfunction-more effectively than those from the 1st extraction. Conclusions: To enhance the cognition-improving activity of white ginseng extract, it is suggested that the extracts be utilized after being combined the 1st extracts (made with EtOH/$H_2O$ solvent) and the 2nd extracts (prepared with $H_2O$) at low temperature.

• Journal of Pharmaceutical Investigation
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• v.31 no.3
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• pp.197-200
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• 2001

Lectin-conjugated ellagitannin (LET), a newly introduced melanoma-specific antitumor agent which has been synthesized by conjugation of wheat germ agglutinin as a lectin with praecoxin A as an ellagitannin, was encapsulated into sterically stabilized liposomes (SSL). Modified Folin phenol method was established for the quantitation of LET contents in liposomal formulations protein employing the standard calibration curve with bovine serum albumin. After removal of phospholipid by organic solvent extraction, which interferes the specific selectivity of the Folin-Ciocalteu reagent with the protein, recovery of LET was $94.5{\pm}2.3%$ and the encapsulation efficiency was revealed as $37.8{\pm}5.9%$ for 2.5 mg/ml LET solution.

• Bulletin of the Korean Chemical Society
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• v.32 no.5
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• pp.1564-1568
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• 2011

A solvent extraction separation, preconcentration and determination of thorium with a new crown, 2-ethyl-N-benzyl-4,7,10,13,16-pentaoxa-1-azacyclooctadecane (MACE), is described in the study. The amount of thorium in the aqueous phase and organic phase was determined by Inductively Coupled Plasma-Optical Emission Spectroscopy and Ultraviolet-Visible, respectively. Thorium loaded organic phase was quantitatively stripped in a stage by using 1.0 M $HNO_3$. Thorium was effectively extracted with MACE in the pH range of 6-7 to produce a 3:2 complex ratio in the chloroform. A highly sensitive and rapid spectrophotometric method was described for determination of trace amounts of thorium with MACE. The effective molar absorption coefficient at 281 nm is $1.98{\times}10^3\;mol^{-1}cm^{-1}$, and the system complies with Beer's law in the range from 0.464 to 2.32 ${\mu}gm\;L^{-1}$ of thorium. Thorium was also determined in standard and environmental samples.