• Journal of Soil and Groundwater Environment
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• v.17 no.1
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• pp.42-46
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• 2012

The ISO document of ISO/TC/190/SC3/WG11/N11 is a working draft of international standard (WD) dealing with analytical method for the determination of explosives and related compounds using high performance liquid chromatography. The scope of this WD covers the storage of samples, preparing test portion, extraction and instrumentation. The main purpose of this study was to improve the extraction conditions which were already adopted in the WD. For this purpose, mechanical shaking method could be corresponded up to 18 hours of ultrasonic bath extraction in the WD was tested. Methanol was also tested with the intention of being added as an extracting solvent other than acetonitrile in the WD. According to the results, 16 hours of mechanical shaking method showed statistically the same effectiveness as that of 18 hours of ultrasonic bath extraction. In case of extracting solvent, methanol also showed statistically the same extraction capability as acetonitrile for DNB, TNT, 2-A-DNT and 2,4-DNT. However, the recovery rate of TNB with methanol extraction was 40% higher than that of acetonitrile extraction. Through adding mechanical shaking method into committee draft (cf. the next stage draft of the WD during the process for making international standard), ISO standard of analyzing explosives and related compounds in soil would become more useful in dealing with huge number of field samples in the laboratory. In other aspect, adopting methanol as an alternative extracting solvent would be very effective in the terms of exchangeability with GC-ECD/MS method which is being developed by German experts.

• Korean Journal of Medicinal Crop Science
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• v.24 no.1
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• pp.47-54
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• 2016

Background : A new extraction method-heated ultrasonic extraction was qualitatively and quantitatively analyzed for the extraction of major ginsenosides from ginseng extract; this new high-performance liquid chromatography (HPLC) method was compared with the official extraction method of Korean industrial standards and standard for health functional food. Methods and Results : Ginsenoside compounds were analyzed for 35 minutes by the new HPLC analysis method using a Halo$^{(R)}$ RP-Amide column. The new HPLC analysis method was validated by the measurement of intra-day and inter-day precision, accuracy, limit of detection (LOD), and limit of quantification (LOQ) of each ginsenoside. The correlation coefficients (r2) for the calibration curves of the ginsenoside compounds were over 0.9997 in terms of linearity. The heated ultrasonic extraction method using ultrasonication for 30 minutes at $50^{\circ}C$ yielded higher amount of ginsenosides than the extraction method of the Korean industrial standards owing to the enhancement of extraction efficiency. Conclusions : Compared to the other extraction methods, the heated ultrasonic extraction method yielded a higher amount of ginsenoside Rb1 than Rg1 index compounds for the quality evaluation of ginseng roots.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.26 no.3
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• pp.307-316
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• 2016

Objectives: In general, NIOSH method 5506 is most widely used for the occupational exposure measurement of PAHs, but 2-4 ring PAHs have poor desorption efficiency, especially for a filter. The purpose of this study was to determine a method to increase the desorption efficiency of 16-PAHs using an ultrasonic extraction procedure. Methods: Test samples prepared spiked XAD-2 tubes and PTFE filters in the range of $0.01-1.0{\mu}g/mL$ for desorption efficiency study. Four different extraction solvents, acetonitrile, acetone, tetrahydrofuran and dichloromethane, were tested in order to select the most suitable solvent for the extraction of the 16 PAHs. The addition of dimethyl sulfoxide and sonication time were considered in order to determine the method with the highest extraction efficiency. All samples were made in three sets and analysis was replicated seven times by HPLC. Results: Acetonitrile and acetone were the optimized as an extraction solvent and desorption efficiency of 2-ring PAHs such as naphthalene, acenaphthylene were increased 3~19% with dimethyl sulfoxide for XAD-2. Acetone was the best extraction solvent for PTFE filter and the desorption efficiency was increased 3~13% for 2- to 4-ring PAHs. The optimum sonication time was 60 minutes and desorption efficiency increased with extraction time. Conclusions: As a result, the best extraction solvent was acetone with dimethyl sulfoxide for ultrasonic extraction procedure and the desorption efficiency of this method was better than NIOSH 5506's. This study could be applied as a method for occupational exposure measurement of PAHs.

• Journal of Biosystems Engineering
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• v.28 no.4
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• pp.325-334
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• 2003

Pinosylvin, a stilbenoid phytoalexin, is a health ingredient to be extracted from pine leaves. In this study, ultrasonication-assisted extraction process for manufacturing extracts with high content of pinosylvin from pine leaves was investigated. As process and system variables, ultrasonic power, sonication time and solvent ratio were selected. According to the experimental results, the effective yield of pinosylvin increased with the increase of ultrasonic power and sonication time and the decrease of solvent ratio. When the ultrasonic power of 2400 W/L was added to the solution of pulverized pine leaves of 8 g per 1 L of a solvent for 10 minutes, yield of extracts and purity, effective yield and concentration ratio of pinosylvin were 0.3166 g/g, 0.7247 mg/g, 0.2294 mg/g and 23.0, respectively.

• Journal of the Korean Ceramic Society
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• v.38 no.10
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• pp.921-927
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• 2001

An effect of ultrasonic irradiation for the extraction and synthesis of alumina from kaolin was investigated by comparing ultrasonic irradiation method and conventional method with the same factors as reaction time, reaction temperature, and acid concentration. The ultrasonic irradiation method accelerated alumina extraction in comparison to conventional method at $60{\sim}80^{\circ}C$ for $1{\sim}6\;h$ in $1{\sim}5\;M$ ${H_2}{SO_4}$. The characteristics of precipitates and calcined samples, synthesized under the ultrasonic irradiation method and the conventional method, were determined by the means of DTA/TG, XRD, SEM, PSA, BET, etc. Especially, the calcined sample synthesized under the ultrasonic irradiation method had smaller particle size and larger surface area than that synthesized under the conventional method.

• Analytical Science and Technology
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• v.22 no.2
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• pp.136-140
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• 2009

To improve the carbon recovery yield of chemical pretreatment in soil and sediment for $^{14}C$ age dating using AMS (Accelerator Mass Spectrometry), we have developed ultrasonic method in chemical pretreatment to replace with stirring method which has been generally used in each step of humic acid extraction for soil and sediment samples. Extraction conditions such as ultrasonic power, temperature and reaction time have been optimized. Six times higher carbon recovery yield could be obtained from low carbon content samples using ultrasonic method. We also compared the dating results by AMS obtained using ultrasonic method with the ages of samples treated by the stirring method. It was found that this new method could be applied to the pretreatment process of low carbon content samples for AMS age dating without effects on the dated ages, and with highly improved carbon recovery yields.

• The Korean Journal of Food And Nutrition
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• v.32 no.5
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• pp.504-510
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• 2019

The purpose of this study was to compare the effects of soaking and ultrasonic extraction by observing the change of contents with extraction time of physicochemical properties (solid content, colorness, caffeine, chlorogenic acid, total polyphenols, DPPH, and ABTS). As a result of the analysis, solid content increased with longer extraction time and the whiteness tended to decrease with longer extraction time. Conversely, the extraction of functional materials showed a tendency to increase as the extraction time increased. Caffeine reached the maximum value after two hours soaking, but showed the same result as one hour for sonication. Chlorogenic acid did not show difference from the content of coffee extracted for one hour soaking only by sonication extraction for 30 minutes. The total polyphenols eluted with approximately two hours of soaking even after 30 minutes of sonication. DPPH and ABTS were insignificant in their concentrations, but their antioxidative effect was more than two hours of soaking with only 30 minutes of sonication. Sonication has a short time extraction from a functional aspect (caffeine content, chlorogenic acid, polyphenol content, and antioxidant capacity) and this experiment can provide basic data for the development of innovative recipes.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.45 no.3
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• pp.319-331
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• 2019

This study was conducted to find a solvent, a extraction method and optimized conditions for Artemisia iwayomogi extract. which is effective to anti-inflammatory and antioxidant activity. A. iwayomogi extract by distilled water, ethanol, methanol, hexane and ethyl acetate using ultrasonic, high-pressure and supercritical extraction was investigated for NO inhibitory and DPPH radical scavenging activity. Extract obtained by ethanol and ultrasonic extraction method showed high NO production inhibitory activity, DPPH free radical scavenging activity and yield. Response surface methodology (RSM) was applied to find a optimized ultrasonic extraction conditions. Results showed that the optimum conditions for the higher yield were ethanol solvent of 45.71% concentration with extraction time and ultrasonic power of 63.33min and 308.84 W, respectively. This condition predicted 15.85% yield, but real yield was $16.40{\pm}0.28%$. The optimum conditions for simultaneous anti-inflammatory and antioxidant activity were established as ethanol concentration (80.81%), extraction time (90.00 min) and ultrasonic power (400.00 W). NO production inhibitory and antioxidant activity were $89.77{\pm}1.37%$ and $60.12{\pm}0.39%$, respectively. These results showed similar to the predicted values of 94.54%, 58.03% respectively.

• Bulletin of the Korean Chemical Society
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• v.32 no.8
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• pp.2637-2642
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• 2011

A new ultrasonic-assisted micellar extraction and cloud-point pre-concentration method was developed for the determination of major saikosaponins, namely saikosaponins -A, -C and -D, in Radix Bupleuri by high performance liquid chromatography with evaporative light scattering detection (HPLC-ELSD). The non-ionic surfactant Genapol X-080 (oligoethylene glycol monoalkyl ether) was chosen as the extraction additive and parameters affecting the extraction efficiency were optimized. The highest yield was obtained with 10% (w/v) Genapol X-080, a liquid/solid ratio of 200:1 (mL/g) and ultrasonic-assisted extraction for 40 min. In addition, the optimum cloud-point pre-concentration was reached with 10% sodium sulfate and equilibration at $60^{\circ}C$ for 30 min. Separation was achieved on an Ascentis Express C18 column (100 ${\times}$ 4.6 mm i.d., 2.7 ${\mu}M$) using a binary mobile phase composed of 0.1% acetic acid and acetonitrile. Saikosaponins were detected by ELSD, which was operated at a $50^{\circ}C$ drift tube temperature and 3.0 bar nebulizer gas ($N_2$) pressure. The water-based solvent modified with Genapol X-080 showed better extraction efficiency compared to that of the conventional solvent methanol. Recovery of saikosaponins ranged from 93.1 to 101.9%. An environmentally-friendly extraction method was successfully applied to extract and enrich major saikosaponins in Radix Bupleuri.

• Korean Journal of Plant Resources
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• v.22 no.5
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• pp.381-388
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• 2009

Antioxidant substances were extracted from flowers of Aster scaber, Aster maackii, Coreopsis lanceolata and Coreopsis tinctoria using 2 types of extraction methods- ultrasonic wave and reflux, and antioxidant effects were compared. Higher yield of extract was obtained by ultrasonic wave method in all 4 species. Extraction time was different depending on species, but in all 4 species DPPH and ABTS free radical scavenging and ferrous ion chelating activity were higher or similar by ultrasonic wave than reflux method. Content of total polyphenol and flavonoid was mainly higher by ultrasonic wave than reflux method. Longer the treatment, the more the antioxidant activity and bioactive substances. Anti-lipid peroxidation of ultrasonic and reflux extracts obtained from flowers of Aster scaber and Coreopsis lanceolata were compared. Flower extract of Aster scaber obtained by reflux method showed the highest inhibition effect against peroxidation of linoleic acid, but extract of Coreopsis lanceolata obtained by 15-minute ultrasonic extract showed the highest effect. Ultrasonic wave extraction was more economical and efficient method than reflux extraction.