• Journal of Korean Society on Water Environment
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• v.36 no.1
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• pp.48-54
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• 2020

This paper presents a screening protocol for the selection of solvents available for the solvent extraction desalination process. The desalination solvents hypothetically and theoretically require the capability of (1) Forming hydrogen bonds with water, (2) Absorbing some water molecules into its non-polar solvent layer, (3) Changing solubility for water-solvent separation, and (4) Rejecting salt ions during absorption. Similar to carboxylic acids, amine solvents are solvent chemicals applicable for desalination. The key parameter for selecting the potential solvent was the octanol-water partitioning coefficient (Kow) of which preferable value for desalination was in the range of 1-3. Six of the 30 amine solvents can absorb water and have a variable, i.e., temperature swing solubility with water molecule for water-solvent separation. Also, the hydrogen bonding interaction between solvent and water must be stronger than the ion-dipole interaction between water and salt, which means that the salt ions must be broken from the water and only water molecules absorbed for the desalination. In the final step, three solvents were selected as desalination solvents to remove salt ions and recover water. The water recovery of these three solvents were 15.4 %, 2.8 %, 10.5 %, and salt rejection were 76 %, 98 %, 95 %, respectively. This study suggests a new screening protocol comprising the theoretical and experimental approaches for the selection of solvents for the desalination method which is a new and challenges the desalination process in the future.

• Natural Product Sciences
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• v.13 no.4
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• pp.378-383
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• 2007

Phenathrene derivatives, such as batatasins, are well-known constituents in Dioscorea Rhizoma. Although phenanthrenes have been reported as representative compounds in this plant, standard markers for quality control have been focused on the polar constituents (saponins and purine derivatives). Herein, simple, rapid and reliable HPLC method was developed to determine 3,5-dimethoxyphenanthrene-2,7-diol (DMP) and batatasin-I (BA-I) as non-polar standard maker compounds of Dioscorea Rhizoma. DMP and BA-I were analyzed under optimized HPLC conditions [column: Columbus $5{\mu}$ C18 100A ($30{\times}4.6mm$ i.d., $5{\mu}m$; mobile phase: $H_2O$ with 0.025% $CH_3COOH$ (v/v) for solvent A and $CH_3CN$ with 0.025% $CH_3COOH$ (v/v) for solvent B, gradient elution; flow rate: 2 mL/min; detection: 260 nm), and each experiment was finished within 13 min. Good linearity was achieved in the range from 0.5 to $10.0{\mu}g/mL$ for each compound, and intra- and inter-day precision were in the acceptable levels. The recovery test were performed with three different Dioscorea Rhizoma samples (D. opposita, D. batatas and D. japonica), and showed its accuracy values in the range of 97.2 - 102.8% for three different concentrations of DMP and BA-I. The content levels of DMP and BA-I were ranged under 0.0020%. These results demonstrated that amounts of DMP and BA-I are easily determined with conventional HPLC-UV-DAD method although the content levels were lower than those of saponins and allantoin in Dioscorea Rhizoma. This HPLC method could be used for quality control of various Dioscorea preparations.

• Journal of environmental and Sanitary engineering
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• v.16 no.1
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• pp.72-90
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• 2001

This study was conducted to evaluate desorption efficiencies accuracy and precision by $CS_2$ and thermal desorption method for polar and non-polar organic solvents collected on activated carbon(AC), activated carbon fiber(ACF), carbosieve SIII, materials tested were Methyl alcohol, n-Hexane, Benzene, Trichloroethylene, Methyl isobutyl ketone and methyl cellosolve acetate and six different concentration levels of samples were made. The results were as follows ; 1. Accuracy on kind adsorbent and desorption method was low. In case of $CS_2$ desorption solvent, Overall B and Overall CV on AC and ACF were 43% and 6.63%, respectively. In case of thermal desorption method, accuracy of thermal desorption method appeared higher than solvent desorption method by AC 18.0%, 3.54%, ACF 2.6%, 2.57%, Carbosieve SIII 13.7% and 1.97%, respectively. 2. In the concentration level III, accuracy of thermal desorption method on adsorbent was in order as follow ; ACF > Carbosieve SIII > AC in the methyl alcohol and Carbosieve SIII > ACF > AC in the rest of them all subject material and Concentration levels showed good precision at EPA recommend standard (${\leq}{\;}30%$) 3. DEs by type of organic solvent adsorbent and desorption method are as follows ; In the case that desorption solvent is $CS_2$, DE of Methyl alcohol is AC 47.5%, DE of all materials is ACF about 50%. In the case of thermal desorption method, DE of Methyl alcohol is AC 82.0%, ACF 97.4%, Carbosieve SIII 86.3%. DE of the later case is prominently improved more than one of former. In particular, Except that DE of EGMEA is ACF 88.5%, DE of the rest of it is more than 95% which is recommend standard MDHS 72. With the result of this study, in order to measure various organic solvent occurring from the working environment, in the case of thermal desorption method, we can get the accurate exposure assessment, reduce the cost, and use ACF as thermal desorption sorbent which available with easy.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.10 no.1
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• pp.7-14
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• 2004

Migration behavior of selected solvents and food samples showed differences of the chemical structures and polarities, the food samples which have similar polar expresses more higher affinity than different polar degrees. Water which is polar has a highest partitioning coefficient values on polar isopropanol, and oil which is nonpolar has highest partitioning value on non-polar toluene. The increasing order of partitioning values was accord with increasing water contents in food samples. It is showed that the wheat flour with 13.2% moisture content has the highest partitioning coefficient values on the isopropanol with -OH. Kp value of sugar showed remarkable lower partitioning coefficient values than other food samples due to high degree crystallinity. This phenomenon can be predictable with ${\delta}$ values, because order of partitioning coefficient values which comes out through the experiment and the sequence of Hildebrand solubility parameter value difference between food sample and printing ink solvent correspond almost. This Hildebrand solubility parameter value can be easily applied to the food package industry because the effect of food-safety can be considered without passing through complicated steps by using this method.

• Bulletin of the Korean Chemical Society
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• v.24 no.1
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• pp.55-59
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• 2003

This work is focused on analyzing ion-pair interactions and showing the effect of solvent induced inter-atomic attractions in various dielectric environments. To estimate the stability of ion-pairs, SCI-PCM ab initio MO calculations were carried out. We show that the solvent-induced attraction or ‘cavitation' energy of the ion-pair interactions in solution that arises mainly from the stabilization of the water molecules by the generation of an electrostatic field. In fact, even the strong electrostatic interaction characteristic of ion-pair interactions in the gas phase cannot overcome the destabilization or reorganization of the water molecules around solute cavities that arise from cancellation of the electrostatic field. The solvent environment, possibly supplemented by some specific solvent molecules, may help place the solute molecule in a cavity whose surroundings are characterized by an infinite polarizable dielectric medium. This behavior suggests that hydrophobic residues at a protein surface could easily contact the side chains of other nearby residues through the solvent environment, instead of by direct intra-molecular interactions.

• Korean Journal of Food Science and Technology
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• v.25 no.2
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• pp.160-164
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• 1993

The antioxidant activity of ethanol extracts from defatted perilla flour was investigated by measuring peroxide value of perilla oil during storage at $45^{\circ}C$. The antioxidant activity of ethanol extracts was also compared with BHA, BHT and tocopherol. Anti-oxidant activity of ethanol extracts was also examined in corn oil and lard. The ethanol extracts contents of defatted perilla flour and the original perilla seed were 7.69 and 4.56% respectively. The antioxidant activity of ethanol extracts was superior to that of 0.02% BHT, BHA and tocopherol in the perilla oil substrate, merely in concentration of one-twentieth as much as that contained in original perilla oil seeds. The fractions of non-polar solvent (hexane and chloroform) obtained from silicic acid column chromatography are less effective than that of polar solvent as an antioxidant. Antioxidant activity of partially purified ethanol fraction is slightly inferior to that of original crude ethanol extracts. Ethanol extracts were also effective in corn oil and lard almost same as in perilla oil. The total phenolic compound contents of crude ethanol extracts and partially purified ethanol fraction were 9.3, 6.4%, respectively.

• Journal of Adhesion and Interface
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• v.4 no.4
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• pp.1-6
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• 2003

After atmospheric pressure plasma treatment of polypropylene(PP) film surface, we measured the contact angle of the surface by using polar solvent (water) and non-polar solvent (diiodomethane). We also calculated the surface free energy of PP film by using the measured values of contact angles. And then we analyzed contact angle and surface free energy with changing the condition of atmospheric pressure plasma treatment. Upon each condition of atmospheric plasma treatment, contact angle and surface free energy showed an optimum value or leveled off.

• Journal of the Korean Wood Science and Technology
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• v.26 no.3
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• pp.73-80
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• 1998

In order to reconstruct the traditional technology of Korean golden varnish coatings, this study was carried out to separate and determine some main coloring components of the exudates of D. morbifera and its traditionally refined golden varnishes using a process of solvent extractions, chromatographies and spectrometries. The results obtained are as follows: 1. The exudate and its traditional-refined golden varnishes appear to have a kind of natural polyacetylenes because it has some triple bond peaks in FT-IR spectrometry. 2. Some yellowing spots of the polar-solvent extrats from the exudates and refined varnishes separated on TLC appeared under natural drying condition, but those of non-polar solvent extract such as hexane did not. 3. A traditional refining method for reconstructing a Korea golden varnishes was thought to be better than solvent separation because the former had higher triple-bond peaks than the latter in FT-IR spectrometry. 4. One of main conponents in the hexane-extracts of the traditional-refined varnishes and the exudates had the same molcular weighr of 204, but the fragmentation patterns was a little different between the exudate and the refined. in LC-MS soectrometry.

• The Korea Journal of Herbology
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• v.29 no.1
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• pp.13-18
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• 2014

Objectives : Iridoid glycoside, swertiamarin is a well known bioactive component found in Swertia japonica Makino (SJ). In this study, we tried to optimize a suitable method which would extract swertiamarin effectively. Methods : Extraction of SJ was carried out by various conditions of time (5 - 60 min), temperature ($30-70^{\circ}C$), solvent (from non-polar to polar), and ratio of solvnet / sample (10 : 1 - 40 : 1) using ultrasonic extractor. Swertiamarin in SJ extracts was quantified by high performance liquid chromatography - Phtodiode array detector (HPLC-PDA) using C18 column and the analytical procedure was validated by evaluation of specificity, range, linearity, accuracy (recovery), precision (intra- and inter day variability), limit of detection (LOD), and limit of quantification (LOQ). Results : An efficient extraction condition for swertiamarin in SJ was optimized using sonicator extraction (temperature $40^{\circ}C$, solvent 20% methanol, solvent / sample (20 : 1), and time 10 min. Analytical procedure was optimized by HPLC-PDA using isocratic solvent system of acetonitrile and water (9 : 91), and the method was validated in regard to linearity (correlation coefficient, $R^2$ > 0.9999), range ($50-1000{\mu}g/mL$), intra- and inter-precision (RSD < 5.0 %), and recovery (99 -103 %). LOD and LOQ were 0.051 and $0.155{\mu}g/mL$, respectively. Conclusion : An optimized method of extraction for swertiamarin in SJ was established through conditions of diverse extraction and the validation result indicated that the method is suited for the determination of swertiamarin in SJ.

• Biotechnology and Bioprocess Engineering:BBE
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• v.6 no.6
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• pp.426-432
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• 2001

Perstractive fermentation is a good way to increase the productivity of bioreactors. Us-ing Propionibacteria as the model system, the feasibility of using supported emulsion liquid mem-brane(SELM) fro perstractive fermentation is assessed in this study. Five industrial solvents were considered as the solvent for perparing the SELM. The more polar a solvent, is the higher the par-tition coefficeint However, toxicity of a solvent also increases with its polarity. CO-1055(indus-trial decanol/octanol blend)has the highest partition coefficient toward propionic acid among the solvents that has no molecular toxicity toward Propionibacteria, A preliminary extraction study was conducted using tetradecane as solvent in a hydrophobic hollow fiber contactor. The results confirmed that SELM eliminates the equilibrium limitation of conventional liquid-liquid extrac-tion and allows the use of a non-toxic solvent with low partition coefficient.