• Clean Technology
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• v.25 no.2
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• pp.140-146
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• 2019

Flammable substances, such as organic solvents, are commonly used in laboratories and industrial processes. The flash point of flammable liquid mixtures is a very important parameter for characterizing the ignition and explosion hazards, and the flash points of mixtures of $C_2{\sim}C_3$ alcohols and 2,2,4-trimethylpentane were measured in the present study. The 2,2,4-trimethylpentane is an important component of gasoline and is frequently used in the petroleum industry as a solvent. Lower flash point data were measured for the binary systems {ethanol + 2,2,4-trimethylpentane}, {1-propanol + 2,2,4-trimethylpentane}, and {2-propanol + 2,2,4-trimethylpentane}. The flash point measurements were carried out according to the standard test method (ASTM D3278) using a Stanhope-Seta closed cup flash point tester. The measured flash points were compared with the predicted values calculated using Raoult's law and also following $G^E$ models: Wilson, Non-Random Two Liquid (NRTL) and UNIversal QUAsiChemical (UNIQUAC). These models were able to predict the experimental flash points for different compositions of {$C_2{\sim}C_3$ alcohols + 2,2,4-trimethylpentane} mixtures with minimal deviations. The average absolute deviation between the predicted and measured lower flash point was less than 1.28 K. A minimum flash point behaviour was observed in all of the systems as in the many observed cases for the hydrocarbon and alcohol mixtures.

• International Journal of Industrial Entomology and Biomaterials
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• v.35 no.1
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• pp.22-29
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• 2017

Increased alcohol consumption is a burden on the world because it is associated with various health problems. However, the effects of silkworms on alcohol metabolism have not been studied yet. The hard-to-eat mature silkworms have become easier to ingest recently due to the development of technology, steam-lyophilising mature silkworm larvae. In this study, we investigated and compared the effects of SMSPs from three silkworm varieties, Baekokjam, Golden-silk and Yeonnokjam weaving white, golden, and light green cocoons on alcohol metabolism in vivo. Sprague-Dawley rats pretreated with three SMSPs (0.1 g/kg or 1 g/kg body weight) or normal diet (AIN-76A) for 2 weeks were subjected to intragastric administration of absolute ethanol (3 g/kg body weight, 3 h). Three SMSPs did not affect the final body weight and liver weight. All 3 SMSPs were effective to reduce the enzymes in alcohol metabolism, alcohol dehydrogenase (ADH) and aldehyde dehydrogenase (ALDH), and liver damage and enzymes involved in liver damage, aspartate aminotransferase (AST) and alanine aminotransferase (ALT). Among SMSP from 3 varieties of silkworm, preadministration of 1 g/kg Baekokjam SMSP showed the most effective suppressive effect on the activities of ADH, ALDH, AST and ALT. The Baekokjam SMSP contained higher amounts of beneficial amino acids than Golden-silk or Yeonnokjam SMSP. These results suggest that Baekokjam SMSP might be used as a new and promising candidate for improving alcohol metabolism and liver injury through promoting rapid alcohol metabolism.

• Journal of the Korean Ceramic Society
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• v.55 no.6
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• pp.562-569
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• 2018

We propose an economic and facile method for the preparation of silica nanoparticles through a two-step process utilizing chlorosilane residues. Mixed chlorosilane residue was alcoholized with absolute ethanol as a first step to form tetraethoxysilane (TEOS). The TEOS was then utilized as a silicon source to synthesize silica nanoparticles in a sol-gel method. The alcoholysis process was designed and optimized utilizing the Taguchi experimental design method and the yield of TEOS was as high as 82.2% under optimal synthetic conditions. Similarly, the Taguchi method was also utilized to study the effects of synthesis factors on the particle size of silica nanoparticles. The results of statistical analysis indicate that the concentration of ammonia has a greater influence on particle size compared to the mass fractions of TEOS and polyethylene glycol (4.6% and 9.7%). The purity of the silica particles synthesized in our experiments is high, but the specific surface area and pore volume are small.

• YAKHAK HOEJI
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• v.49 no.4
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• pp.268-274
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• 2005

Paclitaxel is an effective antineoplastic agent against ovarian, colon and breast tumors. But there have been many difficulties to formulate this drug due to the extremely low aqueous solubility. Paclitaxel is currently formulated in a vehicle composed of Cremophor EL and absolute ethanol mixture which is $5\~20$ fold diluted in normal saline or $5\%$ dextrose solution before I.V. injection. However, this formulation has many problems such as allergic reactions and drug precipitation on aqueous dilution. To overcome these problems, we prepared the micelle and microemulsion systems for parenteral administration of paclitaxel by using glycofurol, $Soluto^{(R)}lHS$ 15 and oleic acid. Phase diagram, pH-rate stability, particle size distributions and pharmacokinetics of the systems were studied. Micelles and microemulsions formulated as nano-particle delivery system were physically and chemically stable. Therefore, these formulations might be the promising alternative candidate for the parenteral delivery of paclitaxel.

• YAKHAK HOEJI
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• v.1 no.1
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• pp.1-2
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• 1948

The finely powdered entire harbs of Polygala japonica Houttuyn, a drug known as Yong Shin-Cho in Korea, were boiled with methanol and from the filtered extract the methanol was distilled off under diminished pressure and the aqueous solution of the residue was evaporated to dryness after being mixed with ignited magnesia. The dried mass was boiled with absolute alcohol, the filtered clear liquid was evaporated to a small volume and the precipitate Saponin produced by mixing with ether was filtered off. When the filtrate was again evaporated to the thickness of a syrup and allowed to cool for a few days in an ice box, crystalls were separated out in about 5% yield, which formed colorless columns, M. P. 142.deg., from methanol and had the formula $C_{6}$ $H_{12}$ $O_{5}$. On heating it with acetic acid anhybride and sodium acetate, its tetraacetyl derivative $C_{6}$ $H_{8}$ $O_{5}$(C $H_{3}$CO)$_{4}$ was obtained and which formed colorless needles, M. P. 62-5.deg., from ethanol. Their melting points, results of elementar analysis and other characteristics agreed with that of Polygalitol and its derivative. Finally they were proved to be identical with Polygalitol and its derivative, respectively, through determination of mixed melting points with the samples. Polygalitol was isolated from several plants of genus polugala e. g. P. amara, P. vulgaris, P. teunifolia, P. senega etc. The authors added to them another instance of identifying Polygalitol from the plant of genus polygala.olygala.

• Journal of Ginseng Research
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• v.22 no.3
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• pp.155-160
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• 1998

This stuffy was carried to establish a new efficient method for the preparation of edible crude ginseng saponin. The conventional butanol extraction and resin adsorption methods were compared for the contents of total crude ginseng saponin and major ginsenosides. Seventy- percent methanol extract was applied to Diaion HP-20 column and the resin was washed with Hn and eluted with absolute methanol. The methanol elute was dried in vivo and analyzed for its ginsenosides. Use of ethanol instead of methanol to make edible crude ginseng saponin gave a similar result. Butanol extraction was performed by the conventional method. The final aqueous layer from butanol extraction was passed through Diaion HP-20 column followed by elution with methanol and Diaion HP-20 passed fraction was extracted with butanol to recover remaining components, respectively, in order to determine saponin loss. TLC and HPLC qualitatively and quantitatively monitored Ginsenosides, respectively. Loss of ginsenosides was higher in butanol extraction method than in Diction HP-20 adsorption method. In addition, saponin fractions prepared by Diction HP-20 adsorption method showed higher content of each ginsenoside, showing 8.2% higher purity than that of butanol extracted fraction. From these results, we propose the resin adsorption method as a new efficient measure for the preparation of crude ginseng saponin, which is edible by using spirit instead of methanol.

• Bulletin of the Korean Chemical Society
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• v.15 no.6
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• pp.473-477
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• 1994

Second-order rate constants have been measured spectrophotometrically for the nucleophilic substitution reactions of aryl substituted benzenesulfonates $(1,\;X-C_6H_4SO_2-OC_6H_4-Y)$ with aryloxides $(Z-C_6H_4O^{-})$ and ethoxide $(EtO^-)$ in absolute ethanol at $25^{circ}C$. The nucleophilicity of aryloxides increases with increasing electron donating ability of the substituent (Z) on aryloxides, and results in a good Hammett correlation with $\sigma^{-}$ constant. The reactivity of 1 toward aryloxides and ethoxide shows also significant dependence on the electronic nature of the substituent X and Y. Large positive ${\sigma}_{acyl}$ values have been obtained for the reaction of 1 with phenoxide and ethoxide, indicating that the leaving group departure is little advanced at the transition-state of the rate-determining step. This has been further supported from the fact that ${\sigma}^-$ constant gives extremely poor Hammett correlation, while ${\sigma}^0$ does reasonably good correlation for the reaction of 1 with ethoxide. Thus, the present sulfonyl-transfer reaction is proposed to proceed via a ratedetermining attack of nucleophile to the sulfur atom of 1 followed by a fast leaving group departure.

• Journal of Applied Biological Chemistry
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• v.64 no.4
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• pp.391-397
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• 2021

Four compounds were isolated from Salvia plebeia aerial parts. Silica gel open column chromatography with a gradient elution system was used to isolate and purify these compounds. Nuclear magnetic resonance spectroscopy and mass spectroscopy were used for structural elucidation and identification, while electronic circular dichroism was used to confirm the absolute configuration. The structures were determined to be 𝛽-sitosterol (1), (-)-1S,5S,8S,10R-1-acetoxy-8-hydroxy-2-oxoeudesman-3,7(11)-dien-8,12-olide (2), ursolic acid (3), and N-methylhydroxylamine (4). Compounds 2 and 4 were isolated for the first time from this plant. Compound 2 was quantitatively analyzed via HPLC/UV. The results showed that the methanol extract of S. plebeia had a higher content of compound 2 (1.20 mg/g) than the ethanol extract (0.55 mg/g). This study could be used as a preliminary step in conducting HPLC/UV analysis of sesquiterpenoids in S. plebeia extract to assess their bioavailability and potency.

• Journal of Apiculture
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• v.33 no.4
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• pp.277-282
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• 2018

Ethanol extracted propolis (EEP) was mixed with honey (honeypolis) to dissolve well in water and in vitro skin irritation test was conducted. In vitro method is designed to predict and classify the skin irritation potential of a chemical by assessment of its effect on $EpiDerm^{TM}$, a reconstituted three-dimensional human epidermis model. Cytotoxicity is expressed as the reduction of mitochondrial dehydrogenase activity measured by formazan production from MTT after a 60 min exposure period. In this study under the given conditions honeypolis showed no irritant effects. Honeypolis meets acceptance criteria if: mean absolute OD 570 nm of the three negative control tissues is ${\geq}0.8$ and ${\leq}2.8$, mean relative tissue viability of the three positive control tissues is ${\leq}20%$, standard deviation of relative tissue viability obtained from each three concurrently tested tissues is ${\leq}18%$. Honeypolis is therefore classified as "non-irritant" in accordance with UN GHS "No Category".

• Bulletin of the Korean Chemical Society
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• v.17 no.4
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• pp.353-357
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• 1996

Second-order rate constants have been measured spectrophotometrically for the reaction of 2,4-dinitrophenyl X-substituted benzenesulfonates with Z-substituted phenoxides in absolute ethanol at 25.0±0.1 ℃. The nucleophilic substitution reaction gives both S-O bond and C-O bond cleavage products. The extent of S-O bond cleavage increases significantly with increasing electron withdrawing ability of the sulfonyl substitutent X, while that of the C-O bond cleavage is independent on the electronic effect of the substituent. On the contratry, the effect of the substituent Z in the nucleophilic phenoxide is more significant for the C-O bond cleavage than for the S-O bond cleavage. Aminolyses of 2,4-dinitrophenyl benzenesulfonate (1) with various 1°, 2° and 3°amines have revealed that steric effect is little important. The extent of S-O bond cleavage increases with increasing the basicity of the amines, but decreases with increasing the basicity of the nucleophilic aryloxides, indicating that the HSAB principle is not always operative. Besides, reactant and solvent polarizability effect has also been found to be an important factor in some cases but not always to influence the reaction site.