• Applied Chemistry for Engineering
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• v.23 no.6
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• pp.529-533
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• 2012

In this study, we compare various physicochemical properties of solvent extracted coals obtained at both mild and high temperature conditions. In order to characterize the extraction behavior, experiments were performed using a sub-bituminous coal (Kideco) and a polar solvent (N-methyl-2-pyrrolidinone, NMP), where the extraction temperature and the effect of solvent recycling were evaluated. As the extraction temperature increased up to $350^{\circ}C$, an extraction yield and a calorific value of the extracted coal increased, while an ash content of the extracted coal decreased. FT-IR results revealed that the surface of the coal extracted at $350^{\circ}C$ was found to contain more amide, aromatic ester, and aliphatic ether groups than that at the lower temperatures. The result of MALDI-TOF/MS analysis confirmed that the smaller molecules with 300~500 m/z were extracted at a mild condition, while the bigger molecules in the range of 500~1500 m/z were extracted at the high temperature.

• Korean Journal of Food Science and Technology
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• v.21 no.6
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• pp.851-856
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• 1989

The physical properties of essential oil of nutmeg extracted in different methods (SDE, Solvent, $CO_2$) were investigated and also the components of essential oil were analyzed using G.C. and G.C./ Mass. Solvent extraction yield was 23% and was higher than those of SDE extraction and $CO_2$ extraction. From the analysis result and physical properties of nutmeg oil, it was conformed that the nutmeg used In this experiment was similar to East Indies type. The content of sabinene was 3.6-14.1%, 28.4-48.7% for myristicin, 1.2-2.1% for elemicin, and 3.6-5.6% for safrole. The camphene was identified in SDE extracts but not in $CO_2$ extracts. The volatile components of SDE extracts and solvent extracts contained large amount of monoterpene and terpene alcohol but $CO_2$ extracts aminly contained aromatic compounds.

• Applied Biological Chemistry
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• v.36 no.4
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• pp.249-254
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• 1993

The dried cinnamon was extracted with water and 70% ethanol and studied for the several extraction conditions of temperature, time, solvent addition ratio and number of extraction on mineral components and physical properties of the extracts. Mineral components significantly increased as the extraction temperature increased. More than 8 hours of extraction showed a little improving while solvent ratio (V/W) up to 60 times (V/W) significantly increased the mineral components, particularly Cu, Zn, Fe, Na in water extracts and Fe, Mn, K in 70% ethanol extracts. Absorbance at 285 mm decreased as the temperature raised up to the range of $60{\sim}80^{\circ}C$. The Hunter a-value was much affected with extraction conditions and L-value and transmittance were changed similarily while pH was little changed.

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 2003.04a
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• pp.125.1-125
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• 2003

호박은 다른 과채류에 비해 기후조건에 대한 적용범위가 넓고, 한국의 기후 풍토하에서 잠재생산 가능성이 대단히 높은 작목의 하나로 간주되고 있으며, 다른 박과 채소보다 병이 심하지 않고 약재를 살포할 필요가 거의 없으므로 무공해 식품으로도 그 가치가 높은 것으로 평가되고 있다. 최근 국민 식생활 패턴이 고급화 됨에 따라 건강을 중요시하는 소비자가 급증하면서 약품이 아닌 식품으로 인체의 조절기능에 초점이 맞춘 다양한 기능성 식품이 생산되고 있는 실정이며, 이 중 녹황색 채소류의 항산화, 항암효과가 알려지고 있어 늙은 호박을 이용한 새로운 형태의 가공제품은 향후 소비자의 구매욕구를 충동하기에 충분할 것으로 판단된다. 따라서 이러한 호박을 이용하여 가공제품을 생산하기 위한 기초자료로서 추출조건에 따른 품질변화를 모니터링하고자 하였다. 호박의 전처리의 경우 박피유무에 큰 차이가 없으므로 공정단계를 최소화하기 위해 박피를 하지 않고 사용하였으며, 파쇄의 형태는 깍둑썰기(4$\times$4$\times$4㎤)를 하여 추출조건에 사용하였다. 추출온도의 경우 호박자체의 색을 유지하는데 효율적인 95$^{\circ}C$에서 행하였다. 시료에 대한 용매비 및 추출시간에 따른 품질의 변화가 많으므로 시료에 대한 용매비(10, 20, 30, 40 50g/100$m\ell$) 및 추출시간(1, 2, 3, 4, 5 hr)에 따른 중심합성실험계획으로 추출하였다. 추출조건에 따른 추출물에 대하여 수율, 당도, 갈색도 및 탁도를 측정하여 시료에 대한 용매비 및 추출시간에 따른 반응표면분석을 실시하였다. 영향도를 분석한 결과 수율은 추출시간에 영향을 많이 받는 것으로 나타났으며, 총당 및 갈색도는 시료에 대한 용매비에 영향을 많이 받으며 탁도의 경우 두 조건 모두에 영향을 받은 것으로 나타났다. 수율에 대한 최적 추출조건은 호박량 10.03% 및 추출시간 2.89hr일 때 가장 높은 수율로 예측이 되었으며, 갈색도의 경우 호박량 15.21% 및 추출시간 1.65hr에서 최소로 나타났다.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.4
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• pp.549-556
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• 2015

This study extracted radish bud (Raphanus sativus L.) and investigated its nitrite scavenging activity, superoxide dismutases (SOD)-like activity, tyrosinase inhibition activity, xanthine oxidase inhibition activity, and angiotensin-converting-enzyme (ACE) inhibition activity according to extraction solvent and sprouting period. For nitrite scavenging activity, each extract recorded its highest level of 81.44~89.71% at pH 1.2. Radish bud extracts on sprouting days 4 and 8 showed greater scavenging activities than those on sprouting day 12 at pH 1.2 and pH 4.0. There were differences in scavenging activity according to extraction solvent based on water extract exhibiting improved scavenging activity. Ethanol extract recorded scavenging activity of 16.12% at pH 6.0, which was similar to those of ethanol and methanol radish bud extracts on sprouting day 12. SOD-like activity of radish bud extracts was in the range of 4.57~27.05%. For comparison purposes, SOD-like activity of L-ascorbic acid was 52.15%, which was higher than that of radish bud extracts. Acetone and methanol extracts showed high SOD-like activities on sprouting day 8. SOD-like activity of radish bud extracts on sprouting day 12 significantly decreased to 4.57~15.59%. Radish bud extracts recorded good tyrosinase inhibitory activities on sprouting 8 and 12, whereas methanol extracts recorded the greatest tyrosinase inhibitory activity at 62.65~84.89%. Radish bud extracts recorded xanthine oxidase inhibition activity of 21.26~29.52% on sprouting day 4, and acetone extracts showed the highest level of xanthine oxidase inhibition activity. Xanthine oxidase inhibitory activity tended to decrease with sprouting period compared early on. ACE inhibitory activity was in the range of 12.48~51.78% according to sprouting period and extraction solvent. Ethanol extracts on sprouting day 8 showed the highest ACE inhibitory activity of 51.78%. These results will hopefully contribute to research into the identification of materials and development of products for natural functional foods.

• The Korean Journal of Food And Nutrition
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• v.17 no.4
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• pp.368-373
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• 2004

Optimal extraction conditions were established from the difference of quality characteristics according to extraction conditions of Ssangwha extracts(SWE). Extract yields of SWE obtained from the established extraction conditions were as follows. The maximum yield was 48.90% at extraction temperature 90$^{\circ}C$ and alcohol concentration 50%, extraction yield and alcohol concentration of extraction solvent was proportioned. Increase of extraction yields at extraction temperature 80∼90$^{\circ}C$ and more than alcohol concentration 30% had slowdown tendency according to increase of alcohol concentration. At this view point, the optimum extraction conditions were alcohol concentration 30% and more than extraction temperature 80$^{\circ}C$. In this study, optimal extraction conditions of SWE were extraction temperature 90$^{\circ}C$ and alcohol concentration 30%.

• Journal of the Korean Society of Food Culture
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• v.19 no.5
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• pp.499-505
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• 2004

The present study was conducted to investigate extraction characteristics and antioxidative activity of Cassia tora L. extracts. Cassia tora L. was extracted by reflux extraction under different extraction conditions including solvent. The solid yield, turbidity, color value, titratable acidity, free sugar contents, electron donating ability and superoxide dismutase-like ability of Cassia tora L. extracts were determined. The highest solid yield value was obtained with water of 10 fold. No significant difference in turbidity and color value were found among the extracts prepared with various extraction solvents, 75% ethanol, 50% ethanol and water. The highest titratable acidity was obtained with 50% ethanol of Cassia tora L.. The free sugar contents of Cassia tora L. extracted with water showed the highest value. Cassia tora L. extracts with water included higher contents of free sugar compared with then of the other solvent extracts, 50% ethanol and 75% ethanol extracts. The total polyphenol compound content of Cassia tora L. extracted with 50% ethanol showed the highest value. Cassia tora L. extracts with 50% ethanol included higher contents of total polyphenol compound compared with those of the other solvent extracts, water and 75% ethanol extracts.

• Journal of Environmental Health Sciences
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• v.23 no.4
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• pp.82-90
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• 1997

This study was conducted to establish an ideal condition for obtaining maximum extraction efficiencies using an array of soil types and under a wide variety of conditions. Nine characteristic compounds were studied: benzene, toluene, ethylbenzene, o-xylene, m-xylene, p-xylene, n-propylbenzene, 1,2,4-trimethylbenzene, and n-butylbenzene which were found in gasoline. Increasing the moisture content resulted in decreased recovery, and recovery of hydrocarbons from wet soils was significantly lower than from dry soils. For the batch extraction process, 4 hours of extraction time was sufficient to give optimum recovery of the contaminants. With methanol as an extraction solvent, maximum recovery time appeared to be reached quicker for BTEX components than with 2-propanol. The 2 to 1 ratio of solvent/soil was chosen as a compromise to provide for the indicated minimum solvent use and high extraction efficiency. The 0.4 mg/g soil contamination was adequate to show quantitative recovery. The percent recovery of BTEX was concentration dependent more than the semivolatile compounds. Methanol and 2-propanol consistently gave higher efficiency than water. Methanol was superior to 2-propanol in removing contaminants from silty clay loam soil. Using the most efficient extraction procedure, the average recovery of the light hydrocarbons from the three soils was 66 percent. Recoveries were also dependent on soil type, solvent type, extraction time, solvent amount, contaminant concentration, and compounds volatility. This study provided a useful screening technique for procedures that can be used to remediate soils contaminated with light hydrocarbons.

• Analytical Science and Technology
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• v.14 no.2
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• pp.103-108
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• 2001

Rare earth elements(REE) were separated by solvent extraction with tri-n-butyl phosphate(TBP) and $NaNO_3$, followed by back extraction with water. The method was applied to the determination of REE to circumvent the spectral interferences of ICP-AES analysis. The effects of the $NaNO_3$ concentration and the addition of hydrophobic solvents on the extraction efficiencies were investigated. Increases of the $NaNO_3$ concentration enhanced the extraction efficiencies of REE, and more than 95% recoveries were obtained at 5M of $NaNO_3$ concentration. On the other hand, addition of hydrophobic solvents lowered the extraction efficiencies. The method was applied to determine the REE in the monazite sample. But the precisions of the analytical results were more than 20%.

• Food Science and Preservation
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• v.9 no.3
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• pp.332-337
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• 2002

This study was undertaken in order to compare reflux extraction(RE) and microwave-assisted extraction(MAE) in extraction efficiency and establish optimum microwave extraction conditions in obtaining Ligularia fischeri extracts. A considerable reduction in extraction time was accomplished by MAE. When 70% methanol 50% methanol 70% ethanol, or 50% ethanol was used, MAE extract contained equal levels of soluble solid and total polyphenol as obtained by RE. The optimum microwave-assisted extraction conditions for Ligularia fischeri were achieved by 120∼150 watts of microwave energy and 4∼8 minutes of extraction time. No significant changes were found in antioxidant activity with DPPH scavenging method over the variation of microwave energy or extraction time. The use of diluted methanol or ethanol improved soluble solid content(30%), total polyphenol content(2.7%) and antioxidant activity(68%).