• Korean Journal of Pharmacognosy
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• v.30 no.1
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• pp.59-64
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• 1999

Supercritical fluid extraction (SFE) technique was applied to extract cytotoxic substances from five medicinal plants including Angelica gigas, Angelica acutiloba, Aralia cordata, Spirodela polyrhiza, Bupleurum falcatum, and Acanthopanax sessiliflorus. The cytotoxicities against P388, A549, and HL-60 cell lines were determined for the supercritical carbon dioxide extracts of five plant materials employed and were compared with those of the conventional organic solvent extracts such as n-hexane, $CHCl_{3}$, and MeOH to evaluate the SFE as an alternative method to conventional organic solvent extraction. In most cases, the SFE extracts of plant materials showed enhanced cytotoxicities when compared with those of other organic solvent extracts. In addition, the optimum temperature and pressure of SFE for extraction of the cytotoxic substances were largely affected by both the plant species and the cell lines tested. These results suggested that SFE could be an alternative to the conventional organic solvent method for the selective extraction of cytotoxic compounds from plants.

• Journal of the Korean Applied Science and Technology
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• v.27 no.3
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• pp.233-239
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• 2010

Supercritical carbondioxide is very effective in removing oils from a variety of seed matrices, devoid of any appreciable amount of phospholipid content. However, the limited solubility of phosphalipids in supercritical carbondioxide leaves behind a potentially valuable by-product in spent seed matrix. Any phospholipid extraction process from the spent matrix must maintain the structure and the quality of phospholipids and must be compatible with the end use of the seed protein meal an animal feed or for human consumption. An initial supercritical carbondioxide extraction of soybean flakes was performed at 32 MPa and $80^{\circ}C$ to extract the oils, leaving the phospholipids in the deflatted soybean flakes, A second step was performed on the defatted soybean flake using $X_{eth}$=0.10, Varying the pressure from 175 MPa to 70.6 MPa and temperature from $60^{\circ}C$ to $80^{\circ}C$. For all supercritical carbon dioxide/ethanol mixture extractions, a fraction rich in phospholipids was obtained. The fractions extracted from defatted soybean flakes were dried and them redissolved in chloroform before HPLC-ELSD analysis. Quantitative and qualitative analysis of phospholipids on soybean seeds, defatted soybean flake, and different extracted phospholipid fractions was carried out, to ascertain the effect of extraction pressure and temperature.

• Resources Recycling
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• v.29 no.4
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• pp.51-57
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• 2020

Separation of Co and Ni over Mg from the sulfuric acid solutions using Cyanex272, PC88A and Versatic acid 10 as an extractant was carried out. From the comparative studies about the extraction behavior of Co, Ni and Mg, Versatic acid 10 was superior to Cyanex272 and PC88A for the selective extraction of cobalt and nickel from the mixed solutions. About 98% of Ni and Co were extracted at equilibrium pH 7.0 and less than 5% of Mg was co-extracted by Versatic acid 10. McCabe-Thiele diagram indicated two stages requirement for Co and Ni extraction by 10% Versatic acid 10 at pH 7.0 and phase ratio (A/O) of 2.0. The loaded Co and Ni in organic phase was stripped effectively the sulfuric acid concentration above 70 g/L. 99.78% of cobalt and 98.42% of nickel were stripped.

• Applied Chemistry for Engineering
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• v.5 no.1
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• pp.149-159
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• 1994

The kinetics and equilibrium of metal extraction by benzamidoxime and phenylacetamidoxime-chloroform were investigated to apply amidoxime to metal extraction as chelating agent. The overall extraction constant extraction mechanism and selective extraction of copper were examined from the relation among extraction ratio, hydrogen ion concentration and extractant concentration. The experimental rate equation of copper extraction coincided with the theoretical rate equation and was expressed as $R_o=k{\overline{C}}_{HRo}(C_{Mo}/C_{Ho})^{1/2}$. The chemical species extracted was found to the type of ${\overline{CuR_2}}$.

• Journal of Environmental Health Sciences
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• v.21 no.3
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• pp.87-95
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• 1995

A rapid and selective co-extraction systems of copper and zinc-thiocyanate complex into various types of alkylamine for the simultaneous determination of two metal ions by atomic absorption spectrometry and ion chromatograph have been proposed. The quantitative extractions of Cu(II) and Zn(II) at 0.1 M-thiocyanate and 0.1 M-HCI were achieved with Aliquat 336-$CHCl_3$. The detection limits of Cu and Zn were 2 ppb and 0.9 ppb respectively.

• Food Science and Biotechnology
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• v.14 no.1
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• pp.131-136
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• 2005

The selective extraction behavior of lactoferrin (Lf) from whey protein mixture was examined using reverse micelles formed by the cationic surfactant, cetyldimethylammonium bromide (CDAB). The major whey proteins, including ${\beta}$-lactoglobulin, ${\alpha}$-lactalbumin and bovine serum albumin, were solubilized from aqueous phase to organic phase while Lf was recovered in the aqueous phase. The solubilization behaviors of the proteins were manipulated by the process parameters such as the pH and salt concentration of the aqueous phase and the surfactant concentration in the organic phase. Efficient forward extraction was achieved with sodium borate buffer (50 mM, pH 9) containing 50 mM KCl and organic phase containing 100 mM CDAB. Based on SDS-PAGE and densitometry, about 96% of the initial Lf remained in the aqueous phase after forward extraction. The dialyzed Lf fully maintained its bacteriostatic activity against E. coli O157:H7.

• Journal of Electrical Engineering and Technology
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• v.10 no.3
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• pp.1227-1232
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• 2015

Several works help make sliding window object detection fast, nevertheless, computational demands remain prohibitive for numerous applications. This paper proposes a fast object detection method based on three strategies: cascade classifier, selective window search and fast feature extraction. Experimental results show that the proposed method outperforms the compared methods and achieves both high detection precision and low computation cost. Our approach runs at 17ms per frame on 640×480 images while attaining state-of-the-art accuracy.

• Journal of the Korean Institute of Telematics and Electronics C
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• v.34C no.1
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• pp.59-64
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• 1997

By using a selective learnable self-organizing feature map(SOFM) a more practical and generalized mehtod is proposed in which the effective nonlinear shape restoration is possible regardless of the existence of the distortion modelss. Nonlinear mapping relation is extracted from the distorted imate by using the proposed selective learning SOFGM which has the special property of effectively creating spatially organized internal representations and nonlinear relations of various input signals. For the exact extraction of the mapping relations between the distorted image and the original one, we define a disparity index as a proximal nmeasure of the present state to the final idealy trained state of the SOFM, and we used this index to adjust the training of the mapping relations form the weights of the SOFM. Simulations are conducted on various kinds of distorted images with or without distortion models, and the results show that the proposed method is very efficeint very efficient and practical in nonlinear shape restorations.

• Journal of the Korean Society of Food Science and Nutrition
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• v.28 no.5
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• pp.973-979
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• 1999

Volatile compounds from twigs, needles and sprouts in Pinus densiflora were extracted with n hexane, diethyl ether or ethanol for 24 hours, and the extracted compounds were separated and identified by gas chromatography and mass selective detector. The kinds and amount of volatile compounds extracted from three parts of Pinus densiflora were different in solvent extraction and the extraction by the modified Liken Nickerson apparatus. The contents of volatile compounds of twigs contained more than those of needles and sprouts, and the volatile compounds were extracted more in n hexane than the others. In the extraction with hexane, the main volatile compounds of twigs were 18.5% pinene, 14.5% limonene, 12.7% pinene and 3.2% myrcene. Sprouts were 16.8% limonene, 4.4% pinene, 4.3% pinene and 1.7% myrcene. Needles contained 14.7% pinene, 5.4% pinene, 2.2% limonene and 0.8% myrcene. The highest yield for pine aroma was shown in the extraction from pine twigs with n hexane, and in this extraction the amounts of pinene, pinene and limonene were 742 g, 1108 g and 922 g per gram sample, respectively.

• Proceedings of the Korean Nuclear Society Conference
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• 2003.05a
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• pp.306-306
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• 2003