• Applied Chemistry for Engineering
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• v.9 no.1
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• pp.76-81
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• 1998

Physical adsorption on a silica gel(pore size of 80 nm, particle size of $10{\mu}m$)has been studied for binary mixture of acetone diluted in $CO_2$ by use of a FTIR transmission technique and we have compared the result of FTIR transmission technique with that of a chromatographic technique. Measurements were made at 313.2 K and under pressures up to 15MPa. As the pressure increases from 0.1MPa, the IA(Integral Absorbance) of the hydrogen-bonded OH groups interacting with acetone and adsorbed amount by use of a chromatographic technique increases at first, and reaches a maximum at a pressure below the critical pressure of $CO_2$, and then the intensities decrease gradually with increasing pressure. It is found that the pressure dependency of the chromatographic isotherm is a little larger than that of spectroscopic isotherm in the supercritical fluid region. This difference might be attributable to the weaker van der Waals force and relatively stronger hydrogen-bonding force influencing the adsorption of acetone on the sllica gel. The unique spectroscopic characteristics of amine group which vibrational frequencies of hydroxyl groups on the silica gel surface shift downward to about $1300cm^{-1}$ were measured from experimental result of triethylamine diluted in $CO_2$ or $N_2$.

• Journal of Food Hygiene and Safety
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• v.26 no.1
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• pp.36-42
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• 2011

In order to optimize the supercritical fluid extraction (SFE) conditions of ginger oleoresin (GO), we conducted an evaluation of quality properties such as yield (%), color, volatile flavor compounds and gingerol components. The extraction yield gained by SFE increased as extraction pressure and temperature increased. The highest yield was $8.96{\pm}0.68%$ at 500 bar $65^{\circ}C$ extraction condition. The total color difference (${\Delta}E$) values decreased at high pressure. In case of the 100 bar pressure conditions, ${\Delta}E$-values increased as the temperature went up. The analysis of the 6-gingerol, 8-gingerol, 10-gingerol, 6-shogaol and curcumin contents decreased at high temperature conditions of identical pressure and increased at high pressure conditions. The volatile flavor compounds were detected in zingiberene, ${\beta}$-sesquiphellandre, ${\beta}$-phellandre, ${\alpha}{\gamma}$-curcumene, 2,3-butandiol, ${\beta}$-bisabolene and so on. Also volatile component contents showed difference in each of extraction conditions.

• Korean Journal of Food Science and Technology
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• v.31 no.5
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• pp.1268-1274
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• 1999

Pine twigs with buds were cut into $2{\sim}3\;mm$ long pieces and about 18g was used for each experiment. Pressure and temperature ranges employed were $100{\sim}300\;bar$ and $35{\sim}55^{\circ}C$, respectively. Volatile compounds of extracts were isolated and identified by gas chromatography and mass selective detector. Twenty three compounds from the extracts were identified. Limonene and ${\beta}-pinene$ were found to be the major components with $32.6{\sim}43.4%$ being limonene. Extracts obtained by supercritical fluid extraction were lower in monoterpene and higher in oxygenated terpenoids than those by steam distillation and solvent extraction (SDE). Sensory evaluation showed that the pine flavor extracted using supercritical carbon dioxide was much better in quality than that of SDE. In conclusion, it was found out that supercritical fluid extraction can successfully be applied to extract high quality flavor from pine.

• Korean Journal of Food Science and Technology
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• v.37 no.3
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• pp.431-437
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• 2005

Overall experiments were planned by central composite design, and results were analyzed by response surface methodology (RSM) to determine effects of three independent variables, temperature ($X_{1}$), extraction time ($X_{3}$), and pressure ($X_{3}$), on yield of sesame oil extract (Y). Regression equation model optimized by response surface analysis was: Y (sesame oil) = $-3.89+0.07X_{1}+0.03X_{2}+0.0006X_{3}-0.0007X_{1}^{2}-0.0002X_{2}X_{1}-0.00008X_{2}^{2}+0.000004X_{3}X_{1}+0.0000009X_{3}X_{2}-0.00000009X_{3}^{2}$. According to RSM analysis, optimum extracting conditions of temperature, time, and pressure were $45.89^{\circ}C$, 131.89 min, and 34228.41 kPa, respectively, and statistical maximum yield of sesame oil was 96.27%. Fatty acid composition of sesame oil showed sesame oil extracted by Supereritical Fluid $CO_{2}$ contained lower levels of palmitic, stcaric, and oleic acids and higher levels or palmitoleic and linoleic acids than commercial sesame oil. Commercial and extracted sesame oils were analyzed by electronic nose composed of 12 different metal oxide sensors. Obtained data were interpreted by statistical method of MANOVA. Sensitivities of sensors from electronic nose were analysed by principal component analysis. Proportion of first principal component was 99.92%. All sesame oils showed different odors (p < 0.05).

• Korean Chemical Engineering Research
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• v.46 no.4
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• pp.747-751
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• 2008

The effect of additives in the synthesis of biodiesel fuel using supercritical methanol was studied in order to examine the possibility of application of spent vegetable oil as a raw material, which has high contents of water or free fatty acid. The experiments were performed by varying the contents of water, free fatty acid or antioxidants respectively in a batch reactor. The contents of fatty acid methyl ester was analyzed by a gas chromatography. As the water contents increased, the contents of fatty acid methyl ester decreased, however, the decrease was very little compared with the alkaline and acid catalyst. The effect of the contents of free fatty acid, vitamin E, and ${\beta}$-carotene was negligible.

• Korean Journal of Food Science and Technology
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• v.30 no.3
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• pp.574-580
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• 1998

The technical feasibility of removing cholesterol from milk fat by supercritical carbon dioxide $(SC-CO_2)$ extraction followed by adsorption on different adsorbents and of fractionating milk fat into different fatty acid composition at $40^{\circ}C/276$ bar was investigated. Cholesterol could be selectively removed from milk fat by adsorption on a typical commercial florisil with $SC-CO_2$ extraction. Lower weight ratio of milk fat feed to florisil showed higher reduction of cholesterol, but gave lower yield in the milk fat fractions. The effective capacity of florisil for removing cholesterol from milk fat was 2.0g/g, which is the ratio of the fat feed to the adsorbent for 89% cholesterol reduction with a fat yield of 57.5%. Fatty acid composition showed higher short-chain and lower unsaturated long-chain fatty acids in the extracted fractions. Milk fat fractionation method by supercritical fluid extraction in coupled with adsorption would appear suitable for removing undesirable ingredients such as cholesterol and for enriching short-chain fatty acids in the fractions.

• Journal of the Korean Chemical Society
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• v.45 no.2
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• pp.149-155
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• 2001

A new analytical method of cyanobacterial toxins, i, e, microcysins was deveeloped using supercritical fluid extraction(SFE). The microcystins mcluded in the study are sparsely soluble in neat supercritical fluid CO$_2$ However, the microcystins were successfully extracted with a temary mixture(90% CO$_2$,9.0% methanol 1.0% water) at 40$^{\circ}$C and 250 atm. The SFE method developed in this study has several advantages over solid-phase extraction(SPE) sample preparation for the analysis of microcystins. Sample handling steps are minimized thus reducing possible losses of analytes and saving analysis time. No clean-up steps are employed in this SFE method. Althouhgh many methods have been described for microcystim RR and LR, the method using solid-phase extraction with ODS cartridges is the most commonly used. However, the adsorbing power of ODS caridges for microcystins is weak, so we have attempted to use a more polar CN cartridge, to increase the adsorbing power for microcystins. Lyophilized cells(100mg) were wxtracted with 5% (v/v) acetic acid. The extract was centrifuged and then the supernatant was applied to a CN cartridge. The cartridge which contained microcystins was rinsed with 5 ml of water and 5 ml of 0.5 M acetic acid. followed by 5 ml of 5% acetonitrile in water , and were determined by HPLC. Better recoveries and chromatogram were observed than with ODS cartridge.

• The Korea Journal of Herbology
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• v.28 no.6
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• pp.95-100
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• 2013

Objectives : The purpose of this study was to investigate antiaging and antioxidant effects on cultured human skin fibroblast with supercritical fluid extracts of Dendropanax morbifera, Corni fructus and Lycii Fructus. Methods : Supercritical fluid extraction (SFE) technique was applied to extract from three medicinal plants including stem of Dendropanax morbifera, Corni fructus and Lycii Fructus. Antioxidant activity of extract was evaluated by two different assays as 2,2-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging and super oxide dismutase (SOD) like activities. These extracts were tested for cell viability on HS68 skin fibroblast by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide (MTT) assay. We investigated the effects of Ultraviolet-B irradiation on cytotoxicity, type 1 collagen, elastin level and oxidative damage in cultured human skin fibroblast (HS68). Recently, many studies have reported that elastin is also involved in inhibiting or repairing wrinkle formation, although collagen is a major factor in the skin wrinkle formation. Results : The extracts obtained dose-dependently increased the scavenging activity on DPPH radical scavenging activity and SOD like activity. The supercritical fluid extracts of complex herbal medicine showed low cytotoxicity as more than 100% cell viability in 100ppm/ml concentration. HS68 fibroblasts were survived 70% at $120mJ/cm^2$ UVB irradiation and treated tumor necrosis factor (TNF)-alpha. The levels of aging factors and cytotoxicity were decreased by supercritical fluid extract of complex herbal medicine. Conclusions : These results suggest that supercritical fluid extracts may have value as the potential antioxidant and antiaging medicinal plant.

• Korean Journal of Food Science and Technology
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• v.37 no.2
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• pp.183-188
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• 2005

Effects of co-solvent polarity, citric acid, pressure, temperature, run time, and co-solvent ratio on extraction of major flavonoids from Lonicera Flos were investigated using supercritical fluid $CO_{2}(SF-CO_{2})$. HPLC analysis revealed addition of pure methanol resulted in low extraction yield of major flavonoids, luteoloin (Lu), Quercetin (Qu), Apigenin (Ap). Under same condition, as co-solvent polarity increased, yields of major flavonoids increased gradually, At optimum co-solvent extraction condirion of 60% aqueous methanol (10%, v/v), yields of Lu, Qu, and Ap were 42.09, 28.18, and 3.49 mg/100 g, respectively. Addition of citric acid to 60% aqueous methanol gave higher, with addition of 1% citrie acid resulting in highest yields of 63.2 (Lu), 39.35 (Qu), and 5.79 (Ap) mg/100 g. Optimum extraction conditions of major flavonoids were 200 bar, $50^{\circ}C$, 60 min, and $CO_{2}$-methanol-water(20: 1.8: 1.2).

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.46 no.6
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• pp.56-62
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• 2014

This study aims to investigate the applicability of supercritical fluid extraction as a dewaxing technique to restore the beeswax-treated volume of the Annals of the Joseon Dynasty in various deterioration and damage conditions. Thus, this study analyzed the dewaxing efficiency and changes in physical and morphological properties before and after dewaxing, by applying the optimal supercritical fluid extraction dewaxing condition ($70^{\circ}C$, 40 MPa, $CO_2$, Co-solvent 20% DCM, 2 hour) to 3 kinds of beeswax-treated paper with different deterioration rates (dry artificial aging of 10, 20 and 30 days at $120^{\circ}C$). After dry artificial aging at $120^{\circ}C$ for 30 days, the average molecular weight of the beeswax-treated specimen was $1.856{\times}10^5g/mol$, showing deterioration about 80% of the beeswax-treated paper before dewaxing. It was a similar level to the molecular weight of the bees-waxed volume of the Annals of the Joseon Dynasty that has a higher degree of damage. As a result of analyzing the dewaxing efficiency through FT-IR analysis, this study discovered that it was possible to effectively dewax beeswax-treated paper in the range of deterioration 20 to 80% with this supercritical fluid extraction dewaxing technique applied. As a result of analyzing changes in the physical and morphological properties before and after dewaxing, the viscosity tended to decrease to a slight degree, and since no morphological deformation or damage of stencil fibers was found, it was concluded possible to conduct stable dewaxing through this supercritical fluid extraction technique.