• Bulletin of the Korean Chemical Society
• /
• v.20 no.6
• /
• pp.689-695
• /
• 1999

Supercritical fluid extraction (SFE), ultrasonic extraction (USE), and accelerated solvent extraction (ASE) were compared with the well known Soxhlet extraction for the extraction of polychlorinated biphenyls (PCBs) and polychlorinated dibenzo-p-dioxins(PCDDs) from the XAD-2 resin which was used to adsorb PCDDs in the atmosphere. XAD-2 resin spiked with five PCDDs was chosen as a sample. The optimum conditions for the extraction of PCDDs by SFE were turned out to be the use of CO2 modified with 10% toluene at 100 ℃ and 350 atm, with 5 min static extraction followed by 20 min dynamic extraction. SFE gave a good extraction rate with good reproducibility for PCDDs ranging from 68 to 98%. The ultrasonic extraction of PCDDs from XAD-2 was investigated and compared with other extractions. A probe type method was compared with a bath type. Two extraction solvents, toluene and acetone were compared with their mixture. The use of their mixture in probe type, with 9 minutes of extraction time, was found to be the optimum condition. The average recovery of the five PCDDs for USE was 82-93%. Accelerated solvent extraction (ASE) with a liquid solvent, a new technique for sample preparation, was performed under elevated temperatures and pressures. The effect of tem-perature on the efficiency of ASE was investigated. The extraction time for a 10 g sample was less than 15 min, when the organic solvent was n-hexaneacetone mixture (1 : 1, v/v). Using ASE, the average recoveries of five PCDDs ranged from 90 to 103%. SFE, USE, and ASE were faster and less laborious than Soxhlet extraction. The former three methods required less solvent than Soxhlet extraction. SFE required no concentration of the solvent extracts. SFE and ASE failed to perform simultaneous parallel extractions because of instrumental limitations.

• Korean Chemical Engineering Research
• /
• v.53 no.4
• /
• pp.445-449
• /
• 2015

This study was directed to finding an optimum extraction condition of genistein from the S. flavescens with supercritical carbon dioxide as a solvent. In this effort, effects of the extraction conditions including pressure, temperature and a co-solvent on the extraction efficiency were investigated. The aqueous ethanol and methanol solutions were used as co-solvents while the tested operating pressure and temperature ranges were from 200 bar to 300 bar and from 308.15 K to 323.15 K, respectively. The concentration of genistein was determined by means of HPLC equipped with a UV detector. From the results, it was observed that an increase in pressure led to the higher extraction efficiency. Further, methanol showed better performance as a co-slovent than ethanol. The DPPH radical scavenging activities were measured to compare antioxidant activities of S. flavescens extracts.

• The Korea Journal of Herbology
• /
• v.28 no.6
• /
• pp.47-51
• /
• 2013

Objectives : The Illicii Veri Fructus was not only traditional medicine but also food in Asia. The aim of this study was selection of optimum solvent in the fruit of Illicii Veri Fructus because an appropriate solvent affect a medicinal effect. Methods : Illicii Veri Fructus was carried out ultrasonic-assisted extraction as various solvents. Two main compounds, p-anisaldehyde and anethole, were successfully analyzed by high performance liquid chromatography-photodiode array detector (HPLC-PDA) and carried out method validation according to ICH guideline. The optimum solvent selected by comparing with yields of two main ingredients. Results : The p-anisaldehyde and anethole were detected at approximately 8.0 min and 19.8 min, respectively. It was all below 5.0% that RSD of retention time and peak area for two main peaks. Calibration curves of two compounds were good linearity as $R^2$ >0.9999. All of the precisions and accuracy were good intra-day and inter-day as below 5.0% RSD. Limited of detection (LOD) of p-anisaldehyde and anethole were analyzed as $0.134{\mu}g/mL$ and $4.286{\mu}g$, respectively. Limited of quantification (LOQ) of two compounds were $0.407{\mu}g$ and $12.989{\mu}g$, respectively. As a result of this study, p-anisladehyde was detected as 0.209 ~ 0.467%, however anethole was not detected in the distilled water. Conclusions : Anethole was main component as 5.329 ~ 6.815% except for water extraction. Methanol extraction among various solvents was detected the highest contents of p-anisaldehyde and anethole as 0.467(${\pm}0.008$)% and 6.815(${\pm}0.220$)%, respectively.

• Journal of the Korean Society of Food Culture
• /
• v.11 no.3
• /
• pp.403-408
• /
• 1996

This study was carried out to investigate the volatile flavor compounds of Pinus densiflora Sieb & Zucc according to extraction solvents and steam distillation method. The research results are as follows: 29 kinds of components were extracted by extraction solvents. Hydrocarbon was the major flavor components of the Pinus densiflora Sieb & Zucc. When the flavor components were extracted by solvents and analyzed by GC-Mass, in the hexane, ${\alpha}$-pinene was the highest and the contents ${\beta}$-thujene, trans-caryophyllene, ${\beta}$-mercene, ${\beta}$-cubebene were higher; in the ethyl acetate, the ${\alpha}$-cubebene content was the highest and the contents ${\alpha}$-cubebene, 3,6,9,12,15-pentaoxanonadecan-1-ol, camphene were higher; in the ethanol, the ${\beta}$-D4-tetrahydropyran was the highest and the contents ${\gamma}$-cadinene, 3-ethyl-1,4-hexadiene, ${\alpha}$-cubebene were higher. When the volatile constituents were extracted by steam distillation method, 44 kinds of components were extracted. Hydrocarbon was the major flavor components of the Pinus densiflora Sieb & Zucc. The ${\beta}$-cubebene content was the highest and the contents trans-caryophyllene, 2-hexenal, T-muurolol, ${\delta}$-cadinene were higher. This fact indicated that volatile constituents differ depending upon the extracting solvents and method.

• YAKHAK HOEJI
• /
• v.36 no.6
• /
• pp.563-569
• /
• 1992

The sorption and desorption properties of four different solid adsorbents were evaluated for the trace enrichment of ibuprofen from biological samples. Chromosorb 107 gave the highest dynamic adsorption coefficient. Among the organic solvents examined, acetone gave the highest desorption coefficient. Using the Chromosorb 107 column, the optimum elution volume of the eluting solvent was evaluated from the breakthrough curve of ibuprofen. The usefulness of Chromosorb 107 as the solid adsorbent and acetone as the eluting solvent was examined for the solid-phase extraction of ibuprofen from serum in the concentration range of $20{\sim}40\;{\mu}g/ml$.

• YAKHAK HOEJI
• /
• v.39 no.4
• /
• pp.395-400
• /
• 1995

The sorption and desorption properties of four adsorbents were evaluated for the trace enrichment of clobazam from biological samples. Graphitized carbon black(GCB) gaved the highest dynamic adsorption coefficient. Among the six organic solvents examined, acetone gave the highest desorption coefficient for the clobazam adsorbed on GCB. Using the GCB column, the optimum elution volume of the eluting solvent was evaluated from the on-line monitored breakthrough curve for clobazam. When GCB as the solid adsorbent and acetone as the eluting solvent were used for the solidphase extraction of clobazam from serum, the recoveries were higher than 83% with good reproducibility in the concentration range of 20-50 $\mu\textrm{g}$/ml.

• Analytical Science and Technology
• /
• v.13 no.3
• /
• pp.399-402
• /
• 2000

To determine the concentrations of microcystins present in lake water or in tap water using high performance liquid chromatography, it is necessary to concentrate a large volume of water samples (about 20 L) into very small volume (0.1-0.3 mL). Concentration can be conveniently done when disc type solid phase extraction (SPE) apparatus is used. Using this apparatus we have investigated the recovery rates of three kinds of microcystins, RR, YR, LR. The recovery rates were relatively low and the reproducibilities were not good either. It is expected, however, that the appropriate selection of the disc conditioning and eluting solvents and reproducible reconcentration process after SPE will improve both the recovery rates and the reproducibilities.

• Journal of Environmental Health Sciences
• /
• v.19 no.2
• /
• pp.16-22
• /
• 1993

In recent years, great concern for the improvement of drinking water quality has been arising due to the contamination of the raw and treated water. So trihalomethanes (THMs) and some other volatile organic compounds (VOCs), potential carcinogenic substances, rendered the government to take some countermeasurements for clean water service in the dimension of public health. In this study, we used liquid-liquid extraction method as a rapid simple method for determination of VOCs through eluation with n-Pentane in water. The aim with the present study has been to determine the changes of recovery and reproducibility of the method under the various conditions in extraction solvents, solvent ratio and extraction time, and to observe the concentrations under the various temperature and pH during storage.

• Journal of the East Asian Society of Dietary Life
• /
• v.3 no.2
• /
• pp.155-163
• /
• 1993

This study was conducted to investigate the optimal condition of the extraction of red pepper oleoresin. The yield of oleoresin form red pepper was 24~28% when it was extracted by ethanol and methanol. and 8~10% by acetone, ethylene dichloride and n-hexane. But more than 60% of portion in alcohol extracts were moisture and sugars. Capsaicin and pigment were extracted more than 70% of those in red pepper when it was extracted by ethylene dichloride Those useful components were extracted most efficiently by mixed solvents of ethanol and ethylene dichloride at the ratio of 50:150. other extracting conditions were investigated in this studies, such as optimal extraction time was more than 3 hours, temperature was 55$^{\circ}C$ and particle size was finer than 250 mesh

• Preventive Nutrition and Food Science
• /
• v.6 no.2
• /
• pp.133-135
• /
• 2001

The edible part of cucurbita moschata Duch, which is commonly used as a Korean traditional medicine as well as a popular food source, was studied to isolate anti-complementary substance. Extracts of Cucurbita moschata Duch showed significant anti-complementary activities on the classical pathway of the complement system. Especially, the ripe Cucurbita moschata Duch had more activity than that of the complement system. Especially, the ripe Cucurbita moschata Duch had more activity than that of the green one in terms of the overall anti-complementary activity. Among the extracts of various organic solvents of the ripe Cucurbita moschata Duch, chloroform and ethyl-acetate extracts, which are non-polar solvent extracts, showed the strongest activities. These results suggest that the major difference in the solvent extraction for the anti-complementary substances depends on the change in the chemical composition such as the fatty acid with the degree of ripening.