• Proceedings of the Korean Society of Crop Science Conference
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• 2018.10a
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• pp.254-254
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• 2018

• Bulletin of the Korean Chemical Society
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• v.4 no.4
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• pp.189-191
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• 1983

• Membrane Journal
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• v.24 no.2
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• pp.113-122
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• 2014

Porous poly(L-lactic acid)(PLLA) scaffold membranes were prepared via. phase separation process. Chloroform, dichloromethane and 1,4-dioxane were used as solvent and, ethyl alcohol was used as non-solvent. Morphologies, mechanical properties and mass transfer characteristics of the scaffold membranes were investigated through SEM, stress-strain test and glucose diffusion test. The scaffold membranes obtained from the casting solutions with chloroform and with dichloromethane showed similar morphologies. They showed sponge-like porous structure with the pore size in the range of $3-10{\mu}m$ and, their porosities were in 50-80% range. Using 1,4-dioxane as solvent, nano-fibrous scaffold membranes with porosities over 80% were fabricated. When the polymer content in the solution with 1,4-dioxane was lowered to 4%, highly porous, macroporous and nano-fibrous scaffold membranes were obtained. The size of the macropore was tens of the microns and the porosity was around 90%. These results indicate that the solvent has significant effect on the scaffold membrane structure and, that scaffold membranes with various structures can be fabricated through phase separation method by choosing solvent and by controlling polymer concentration in the casting solution.

• Journal of Life Science
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• v.27 no.5
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• pp.561-566
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• 2017

Dendropanax morbifera Lev. is known in Korea for its golden sap and medicinal properties. The many biological activities of the leaf and stem extracts suggest that this tree could be a valuable source of medicinal compounds for the treatment of various ailments such as dermatitis, migraines, dysmenorrhea, muscle pain, and infectious diseases. However, there is little information on the composition and biological activity of the volatile fraction of D. morbifera. Therefore, in this study, the volatile compounds in leaves, stems, and sap of D. morbifera were isolated using solvent and supercritical fluid extraction (SFE), and analyzed by gas chromatography/mass spectrometry to reveal their chemical composition and identify potential compounds of interest. Fifteen compounds were identified in the leaf extracts, whereas 29 and 3 compounds were identified in the stem and sap extracts, respectively. The volatile profiles obtained using solvent and SFE differed. Esters and aromatic hydrocarbons predominated in the solvent extract of leaves and SFE extract of stems, whereas the solvent extract of stems and SFE extract of leaves contained terpenoids. Limonene, ${\alpha}$-pinene, and ${\beta}$-myrcene were identified in the volatile extract of sap, with limonene representing 96.30% of the total peak area. In addition, the antiproliferative effects of the solvent extracts of leaves and stems were evaluated, revealing that these solvent extracts were particularly effective in decreasing the proliferation of HepG2 cells.

• International Journal of Industrial Entomology and Biomaterials
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• v.40 no.1
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• pp.28-32
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• 2020

Recently, many studies have been undertaken on the wet spinning and electrospinning of silk because wet-spun fibers and electrospun webs of silk can be applied in the biomedical and cosmetic fields owing to the good biocompatibility of silk. The rheological properties of silk solution are important because they strongly affect the spinning performance of the silk solution and the structures of resultant fibrous materials. Therefore, as a preliminary study on the effect of solvent composition on the rheological properties of silk fibroin (SF) solution and structure of the resultant film, in the reported work, methanol was added to the SF formic acid solution. A small amount of methanol (i.e. 2%) added to the SF formic acid solution significantly altered the rheological properties of the solution: its shear viscosity increased by 10 folds at low shear and decreased on increasing the shear rate, demonstrating shear thinning behavior of the SF solution. Dynamic tests for the SF solution indicated that the addition of 2% methanol altered the viscous state of the SF formic acid solution to elastic. However, the molecular conformation (i.e. β-sheet conformation) of the regenerated SF film cast from formic acid remained unchanged on the addition of 2% methanol.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.30 no.7 s.250
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• pp.663-670
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• 2006

The presented study aims to investigate the colloidal droplet deposition caused by evaporation of the liquid. In the numerical analysis, the evaporation is carried out by using different evaporation function intended to obtain different shape of solute deposition. In the experiment, the colloidal droplets of different solvents are placed on a glass plate and the surface profiles are measured after drying the solvents of the droplets to investigate the effect of the solvent evaporation on the final deposition profile. Comparing the surface profiles obtained under different conditions, the optimum drying conditions of colloidal droplets are, determined to obtain uniform surface profiles. The numerical results showed that ring-shaped deposition of solute was formed at the edge of the droplet due to the coffee stain effect and the height of the ring was reduced at the lower evaporation rate. The experiments showed that the boiling point of a solvent was critical to the surface uniformity of the deposition profile and the mixture of solvents with different boiling points influenced the uniformity as well.

• YAKHAK HOEJI
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• v.31 no.1
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• pp.33-39
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• 1987

In order to elucidate the defence mechanism of Cyprinus carpio nudus to Clonorchis sinensis, clonorchicidal substance in the epidermal mucus of this fish was isolated by silica gel column and thin layer chromatography and analyzed for its chemical nature by UV, IR and NMR-spectroscopy. The epidermal mucus of the fish was extracted by ethyl ether and separated into 2 fractions by column chromatography using petroleum ether/chloroform(30/70,v/v) as first solvent and methanol as second solvent. The second fraction with greyish white colour showed clonorchicidal effect. The second was again fractionated into greyish white precipitate and clonorchicidal greenish yellow supernatant fraction, by adding petroleum ether and standing the mixture for 5 days at $5^{\circ}C$. The latter was divided into 7 fractions in column chromatography with acetone/ benzene (10/90, v/v) as carrier. The fraction on equivalent to the spot of Rf. 0.225 value among them disclosed the strongest clonorchicidal effect. By this purification procedure, clonorchicidal substance was purified 154-fold with 0.9% yield from the mucus of the fish, and 10mg of the final fraction killed tne metaceicariae in 22 min. Infra red, nuclear magnetic resonance and ultraviolet spectrometric analysis of the purified substance revealed that the substance is linoleic acid. According to the results of the present studies it seemed that this fish could not be proper intermediate host of Clonorchis sixensis, and that defence mechanism of this fish to the worm seems to be correlated with clonorchicidal substance in epidermal mucus.

• Korean Journal of Pharmacognosy
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• v.46 no.3
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• pp.229-233
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• 2015

The anti-nociceptive effect of an ethanol extract and its various solvent fractions from Curcuma longa Linne ethanol extract was studied using the writhing test in mice. Different fractions by various solvent extraction from Curcuma longa Linne ethanol extract were administered orally 1 hr or time-course (0.5, 1, 2 and 5 hr) before intraperitoneal injection of acetic acid. After treatment with 30% ethanol extract and n-butanol fraction, CB-1, at a dose of 250 mg/kg, the significant writhing responses were 87.5 ± 13.4 (inhibition rate 31%, p<0.01) and 75.1 ± 11.1 (inhibition rate 41%, p<0.01) lower than the control group. At the dose of CB-1 50 mg/kg and 250 mg/kg, CB-1 showed a similar activity comparing to diclofenac of 10 mg/kg. A time-course experiment was performed, which involved oral administration of CB-1 (250 mg/kg) at 0, 0.5, 1, 2, and 5 hr before acetic acid intraperitoneal injection. The most effective time of CB-1 was 30 min before treatment and persisting until 2 hr. This study showed that Curcuma longa Linne has anti-nociceptive properties comparable with those of diclofenac, which suggests promise for the treatment of intractable visceral pain in humans. Major components of the active fraction are identified as curcumin, cyclocurcumin and demethoxycurcumin.

• Bulletin of the Korean Chemical Society
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• v.32 no.6
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• pp.1897-1901
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• 2011

This report shows the rates of solvolyses for phenyl methanesulfonyl chloride ($C_6H_5CH_2SO_2Cl$, I) in ethanol, methanol, and aqueous binary mixtures incorporating ethanol, methanol, acetone, 2,2,2-trifluroethanol (TFE) and 1,1,1,3,3,3-hexafluoro-2-propanol (HFIP) are reported. Three representative solvents, studies were made at several temperatures and activation parameters were determined. The thirty kinds of solvents gave a reasonably precise extended Grunwald-Winstein plot, coefficient (R) of 0.954. The sensitivity values (l = 0.61 and m = 0.34, l/m = 1.8) of phenyl methanesulfonyl chloride (I) were smaller than those obtained for benzenesulfonyl chloride ($C_6H_5SO_2Cl$, II; l = 1.01 and m = 0.61) and 2-propanesulfonyl chloride ($(CH_3)_2CHSO_2Cl$, III; l = 1.28 and m = 0.64). As with the two previously studied solvolyses, an $S_N2$ pathway with somewhat ionization reaction is proposed for the solvolyses of I. The activation parameters, ${\Delta}H^{\neq}$ and ${\Delta}S^{\neq}$, were determined and they are also in line with values expected for a bimolecular reaction mechanism. The kinetic solvent isotope effect of 2.34 in $CH_3OH/CH_3OD$ is in accord with a bimolecular mechanism, probably assisted by general-base catalysis.

• Preventive Nutrition and Food Science
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• v.14 no.1
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• pp.76-85
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• 2009

This study determined the effect of refrigerated and thermal storage on the volatile profile of commercial aseptic soymilk. Volatile components in commercial aseptic soymilk stored either under refrigerated ($4^{\circ}C$) or thermal ($55^{\circ}C$) conditions for 30 days were periodically analyzed by combined solvent-assisted flavor evaporation-gas chromatography-mass spectrometry (SAFE-GC-MS). The concentrations of most of the volatile components, including aldehydes, ketones, alcohols, acids, nitrogen- and sulfur-containing compounds, alkylfurans, furan derivatives and phenolic compounds, were affected to a greater extent by thermal storage compared with refrigerated storage. Profound increases in some volatile compounds with low odor detection thresholds, such as hexanal, octanal, (E)-2-octenal, (E,E)-2,4-decadienal, 1-octen-3-ol, 3-ethyl-2,5-dimethylpyrazine, 2,3-diethyl-5-methylpyrazine, 2-pentylfuran, 4-hydroxy-2,5-dimethyl-3(2H)-furanone, dimethyl trisulfide, guaiacol, 4-vinylguaiacol and 4-vinylphenol, were observed in thermal stored soymilk. The volatile profile changes caused by thermal storage may influence the aroma quality of thermal-stored aseptic soymilk.