• Journal of Life Science
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• v.13 no.6
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• pp.788-793
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• 2003

Production of chiral phenyl oxirane by Rhodosporidium toruloides SJ-4 was investigated. Racemic phenyl oxirane was kinetically resolved by enantioselective hydrolysis reaction by epoxide hydrolase of R. toruloides in two-phase hollow-fiber reactor system. Dodecane with high concentration of the racemic substrate passed through the lumen side and cell suspension was recirculated through the shell side of the hollow fiber reactor For the removal of phenyl-1, 2-ethandiol to reduce the product inhibition to biocatalysts, another hollow-fiber reactor was employed to extract the diol. Racemic phenyl oxirane up to 300 mM was enantioselectively resolved with high enantiopurity (>99% ee) in hollow-fiber reactor system.

• Membrane Journal
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• v.33 no.6
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• pp.369-376
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• 2023

In this study, the alternative to the energy-intensive conventional vacuum distillation process, an eco-friendly and energy-efficient pervaporation separation was employed in 1,2 hexane diol/water (HDO/water) mixture. The crosslinked PVA-glutaraldehyde was coated inside the alumina hollow fiber membrane (Al-HF). In the HDO/IPA pervaporation separation, optimization of the membrane concerning PVA/GA ratio, curing temperature, and pervaporation operating condition were performed. In the long-term stability test, the sustainable pervaporation separation performance giving flux in the range of 1.90~2.16 kg/m²h, and water content in permeate was higher than 99.5% (separation factor = 68) was obtained from the PVA/GA (molar ratio = 0.08, curing temperature = 80℃) coated Al-HF membrane from HDO/water (25/75, w/w, %) mixture at 40℃. Therefore, this work provides potential and inspiration for PVA-based membranes to mitigate excessive energy requirements in HDO/water separation by pervaporation.

• YAKHAK HOEJI
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• v.40 no.2
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• pp.163-169
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• 1996

Glycosidation of 20(S)-protopanaxadiol obtained by the alkaline hydrolysis of total ginsenosides with 2,3,4,6-tetra-O-acetyl-${\alpha$-D-glucopyranosyl bromide in the presence of $CdCO_3$ in benzene-dioxane gave a mixture of acetylated monoglucosides and diglucosides in a total yield of 68%. Under the same condenstion condition, 20-dehydroxyglucosides were formed by dehydration of 12-O-glucosides. The structures of produced glycosides were elucidated as 3-O-${\beta$-D-glucopyranosyl-20(S)-protopanaxadiol, 12-O-${\beta$-D-glucopyranosyl-dammar-20(22), 24-dien-$3{\beta},12{\beta}$-diol, 3,12-di-O-${\beta}$-D-glucopyranosyl-dammar-20(22), 24-dien-$3{\beta},\;12{\beta}$-diol, respectively.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.44 no.3
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• pp.207-215
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• 2011

An endosulfan degrading bacterial strain, K-1321, was isolated by endosulfan-enrichment culture from a seaside sediment collected at Dadaepo Beach, Busan, Korea. The strain was identified as a Serratia sp. based on the results of morphological, biochemical and 16S rDNA homology analyses. Serratia sp. K-1321 was able to completely degrade 50 ppm endosulfan in culture media and soil within 6 weeks at $25^{\circ}C$. GC/MS analysis revealed that endosulfan diol was an intermediate of the bacterial endosulfan degradation. Considering the above results, we concluded that Serratia sp. K-1321 utilized endosulfan as a carbon source and metabolized endosulfan via a less toxic pathway, such as the formation of endosulfan diol as an intermediate.

• Journal of the Korean Society of Tobacco Science
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• v.31 no.2
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• pp.85-94
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• 2009

This work has been conducted to develop a method for the analysis of neutral volatile flavors and their precursors in tobacco. The neutral volatile compounds and precursors in tobaccos have been investigated by Neutral Volatile scan method(NV scan) using Soxhlet extractor. The method has been used to analyze a range of different tobaccos and tobacco products. Neutral flavor compounds were classified as three sections(1st Volatile Fraction, Breakdown Flavor Products and Cembranoid Precursors). The major components of the First Volatile Fraction were 2-cyclohexene-1-one, 6-methyl-5-hepten-2-one, limonene and phenyl ethanol. The major components of Breakdown Flavor Products were isophorone, solanone, damascenone, 3-hydroxy-$\beta$-damascone, geranyl acetone, $\beta$-ionone, dihydroactinidiolide, norsolanadione, neophytadiene, hexahydrofarnesylacetone, farnesyl acetone and megastigmatrienone. The major cembranoid precursor compounds were dibutyl phthalate, duvatrenediols, 8,12-epoxy-14-labden-13-ol, 11-hydroperoxy-2,7,12(20)-cembratriene-4,6-diol, 12,15-epoxy-12,14-labadien-8-ol, 2,7,11-cembratrien-4,6-diol and 8,13-epoxy-14-labdien-12-ol. The NV scna results of tobacco types(flue-cured, burley and oriental) showed that each tobacco type has a characteristic flavor component profile.

• Proceedings of the Korea Crystallographic Association Conference
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• 2001.11a
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• pp.6-7
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• 2001

• Archives of Pharmacal Research
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• v.22 no.6
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• pp.624-628
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• 1999

A formal asymmetric synthesis of Mugineic acid was accomplished from cis-2-butene-1,4-diol throughcatalytic Sharpless epoxidation oxidations and doupling reaction.

• Journal of the Korean Society of Food Science and Nutrition
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• v.11 no.3
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• pp.81-86
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• 1982

Ginseng saponins separated from Panax ginseng C.A. Meyer were analyzed by high-performance liquid chromatography using a carbohydrate analysis column. The effect on the resolution and retention time of each ginsenosides, as well as the addition effect of n-butanol on a acetonitrile/water system, was examined using various proportions of acetonitrile/water system (80/20-94/6) which have been used with typical solvent of carbohydrate analysis column. The retention time of each ginsenosides was greatly affected by the compositions and mixture proportions of the mobile phase and also markedly increased as the proprotion of acetonitrile in mobile phase increased. It was proved that acetonitrile/water system (80/20) and acetonitrile/water/n-butanol system (86/14/10) were very effective mobile phases for diol and triol sapoin analyses, respectively. According to the result obtained by this method, the PT/PD ratios of white and red ginseng saponins were 0.401 % and 0.561 %, respectively. Red ginseng increased PT/PD ratio, compared with white ginseng. This is attributed to the change of saponin pattern by processing method and the change of PT/PD ratio would greatly influence on the biochemical and pharmacological effects of ginseng and its products.

• Natural Product Sciences
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• v.14 no.2
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• pp.100-106
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• 2008

Column chromatographic separation of the MeOH extract from the aerial parts of Schizonepeta tenuifolia Briquet led to the isolation of twelve terpenes (1 - 11 and 17), four phenolics (13 - 16) and a hexenyl glucoside (12). Their structures were determined by spectroscopic means to be (-)-pulegone (1), piperitenone (2), p-cymene-3,8-diol (3), schizonepetoside A (4), schizonepetoside C (5), (+)-spatulenol (6), ursolic acid (7), $2{\alpha}$,$3{\alpha}$,$24{\alpha}$,-trihydroxyolean-12en-28oic acid (8), $5{\alpha}$,$8{\alpha}$-epidioxyergosta-6,22-diol-$3{\beta}$-ol (9), stigmast-4-en-3-one (10), ${\beta}-sitosterol$ (11), (Z)-3-hexenyl-1-O-${\beta}$-D-glucopyranoside (12), rosmarinic acid (13), apigenin-7-O-${\beta}$-D-glucopyranoside (14), luteolin-7-O-${\beta}$-D-glucuronopyranoside (15), hesperidin (16) and trans-phytol (17). Compounds 2, 3, 8, 9 and 12 were for the first time isolated from S. tenuifolia Briq.

• Proceedings of the Korean Fiber Society Conference
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• 2003.10b
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• pp.167-168
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• 2003

Dimethyl-2,6-naphthalenedicarboxylate(2,6-NDC)와 ethylene glycol(EG)로부터 유도되는 폴리에틸렌 나프탈레이트(PEN)는 폴리에틸렌 테레프탈레이트(PET)보다 열적 및 기계적 특성이 우수한 열가소성 고분자이며[1-2], 폴리에틸렌 글리콜(PEG)은 diol기를 함유한 친수성 고분자로서 의약품 및 기타 가공제로 널리 쓰이는 물질이다. 이미 PET는 이러한 PEC를 PET 합성과정에서 공단량체로 사용해 공중합시킴으로서 친수성을 갖는 PET로 개질하고자 하는 연구[3-4]가 다수 보고되어 왔으나, PEN의 경유는 아직 이에 관한 연구보고가 없는 실정이다. (중략)