• Bulletin of the Korean Chemical Society
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• 제32권7호
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• pp.2212-2216
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• 2011

An ionic liquid-based ultrasonic-assisted extraction method has been successfully applied to the effective extraction of phenolic compounds from Laminaria japonica Aresch. Three kinds of 1-alkyl-3-methyl-imidazolium with different cations and anions were evaluated for extraction efficiency. The results showed that both the characteristics of anions and cations have remarkable effects on the extraction efficiency. In addition, the ionic liquid-based ultrasonic-assisted extraction procedure was also optimized on some extraction parameters, such as ultrasonic power, extraction time and solid-liquid ratio. Compared with the conventional solvent, the optimum approach gained the highest extraction efficiency within the shortest extraction time. Average recoveries of phenolic compounds were from 75.5% to 88.3% at three concentration levels.

• 대한본초학회지
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• 제29권6호
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• pp.1-6
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• 2014

Objectives : This study was aimed to compare Gyejibokryeong-hwan (GBH) decoctions produced using different pressure levels for various extraction times to find the optimal extraction conditions through extraction yield, total soluble solids content (TSSC), hydrogen ion concentration (pH), and the contents of chemical compounds. Methods : Decoctions of GBH were prepared under the pressure levels of 0 or $1kgf/cm^2$ for 30-180 min using water as extraction solvent. The extraction yield, TSSC, and pH were measured, and the amounts of the chemical compounds were determined using high performance liquid chromatography-photodiode array detector. Results : The higher pressure and longer extraction time increased the values of TSSC and extraction yield, while decreased the pH value. The decoctions produced in 180 min by pressurized method and produced in 150 min by non-pressurized method showed maximum values of extraction yield and TSSC with minimum value of pH. The amounts of chemical compounds showed variations in pressurized and non-pressurized decoction during overall extraction times. The influences of pressure and extraction time on extraction yield, TSSC, pH, and the contents of chemical compounds were confirmed by regression analysis, which showed that all extraction values were significantly affected by at least one of two extraction factors, pressure and extraction time. Conclusions : This study suggests that the pressure and extraction time can significantly affect the extraction efficiency of components from GBH decoctions. However, optimal extraction conditions could not be chosen due to the variation of the amounts of chemical compounds.

• Korean Chemical Engineering Research
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• 제55권4호
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• pp.574-577
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• 2017

In Indonesia, vetiver oil is one commodity that plays an important role in the country's foreign exchange earnings. Currently, the extraction of essential oil from vetiver still uses conventional methods. Therefore, the aim of this study was to know and verify the kinetics and mechanism of microwave hydrodistillation of vetiver based on two models. In this study, microwave hydrodistillation was used to extract essential oils from vetiver. The extraction was carried out in nine extraction cycles of 20 min to 3 hours. The rate constant, the equilibrium extraction capacity, and the initial extraction rate were calculated using the two models. Kinetics of oil extraction from vetiver by microwave hydrodistillation proved that the extraction process was based on the second-order extraction model. The second-order model was satisfactorily applied, with high coefficients of correlation ($R^2=0.9427$), showing that it well described the process.

• KSBB Journal
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• 제28권4호
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• pp.238-243
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• 2013

Astaxanthin is one of the carotenoid with strong antioxidant. The conditions of extraction of astaxanthin from Portunus trituberculatus were optimized in this work. Six factors of conditions such as, extraction method, extraction solvent, ratio of solvent to raw material, temperature, and time, were investigated. For the increase of the extraction yield, ionic liquids were used as additives in the extraction solvent. The optimum extraction conditions were found: heat reflux extraction, Dichloromethane/methanol (25:75, v/v) as solvent, 1:30 of the ratio of solvent raw material, $80^{\circ}C$, 90 min, and ionic liquid as additive. As a result, 45.81 ${\mu}g/g$ of astaxanthin was extracted from waste.

• KSBB Journal
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• 제29권2호
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• pp.98-105
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• 2014

Three different types of extraction processes, which used supercritical carbon dioxide ($SCCO_2$) and organic solvent, were attempted to improve the extraction yield of oil from Chlorella vulgaris: cosolvent-modified $SCCO_2$ extraction, $SCCO_2$ extraction with ultrasonic sample treatment in organic solvent, and static extraction with organic solvent followed by dynamic $SCCO_2$ extraction. Among these, the last $SCCO_2$ extraction process was found to be most effective in the extraction of oil. Compared with pure $SCCO_2$ extraction, the extraction yield of oil was observed to increase about 7 times.

• KSBB Journal
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• 제26권5호
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• pp.453-458
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• 2011

In this study, two different extraction techniques, organic solvent extraction and supercritical carbon dioxide ($SCCO_2$) extraction, were employed to evaluate the extraction efficiency of oil from Chlorella vulgaris. In the organic solvent extraction, the effects of various organic solvent on the extraction yield were investigated. The $SCCO_2$ extraction was carried out while varying such operating parameters as temperature, pressure, $SCCO_2$ flow rate, and cosolvent. About 4.9 wt% of oil was extracted from ground Chrollera vulgaris for 18 h when dichloromethane/methanol (2：1, v/v) was used as an extraction solvent. The oil yield of the $SCCO_2$ extraction was found to be very low (0.53 wt%) and to increase up to about 0.86 wt% with the addition of cosolvent.

• 생약학회지
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• 제38권2호통권149호
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• pp.128-132
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• 2007

We investigated the contents of crude saponin in the decoctions of Platycodi Radix prepared by the different extraction processes. Each lyophilized decoctions prepared by the different protocol were suspended in water and partitioned with ethylacetate (EtOAc) and n-butanol (BuOH), which gave the EtOAc fraction, BuOH fraction and the remaining water fraction, respectively. The content of crude saponin, which was estimated as the amount of BuOH fraction, and the HPLC profiles of the BuOH fraction were analyzed, and compared each others. The crude saponin content in the decoctions were increased proportionally to the increment of the extraction time, amount of water, extraction temperature and the number of repetition for extraction. Consequently, the optimized conditions were deduced to be suitable and recommendable for the preparation of Platycodi Radix ; the water amount needed for the extraction be 15-20 volumes to crude material, temperature for extraction be optimal at $85{\sim}100^{\circ}C$, extraction time be more than 5 hours and the repetition of extraction was 2 times.

• 대한화학회지
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• 제37권6호
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• pp.590-598
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• 1993

미국의 환경청이 지정한 129종의 priority pollutants 중 16종의 유기살충제를 대상물질로 선정하여 수질시료 중의 극미량 분석방법을 연구하였다. 분석방법으로는 기체크로마토그래프-전자포획 및 기체크로마토그래프/질량분석기-SIM(selected ion moitoring)법을 검출방법으로 정하고, 시료용액의 추출 및 농축방법으로는 용매추출법(liquid-liquid extraction)과 고체상 추출법(solid-phase extraction)을 비교 연구하였다. 각 화합물들의 회수율, 상대표준편차 및 검출한계 등을 측정하여 EPA 분석법을 대체할 수 있는지의 가능성을 조사하였다.

• Korean Chemical Engineering Research
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• 제57권2호
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• pp.301-304
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• 2019

Microwave was designed for lipid extraction from green algae (Spirulina platensis). Microalgae-solvent (various solvents) were extracted and heated using microwave at 600 W for around 40 min. The maximum yield obtained within this period was 12.530% of lipid compared to just 1.293% for Soxhlet extraction. Lipid analysis revealed that those with higher essential fatty acid content consist of saturated fatty acid (SAFA) and polyunsaturated fatty acid (PUFA) which could be used for biodiesel production.

• Natural Product Sciences
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• 제25권2호
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• pp.150-156
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• 2019

Conventional extraction of oil and azadirachtin, a botanical insecticide, from Azadirachta indica involves defatting the seeds and leaves using hexane followed by azadirachtin extraction with a polar solvent. In order to simplify the process while maintaining the yield we explored a binary extraction approach using Soxhlet extraction device and hexane and ethanol as non-polar and polar solvents at various ratios and extraction times. The highest oil and azadirachtin yields were obtained at 6 h extraction time using a 50:50 solvent mixture for both neem leaves (44.7 wt%, $720mg_{Aza}/kg_{leaves}$) and seeds (53.5 wt%, $1045mg_{Aza}/kg_{leaves}$), respectively.