• Membrane and Water Treatment
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• v.8 no.6
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• pp.591-612
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• 2017

Increase in the hydrophilicity (HPCT) of polysulfone (PS) membrane and subsequently decrease in fouling can be achieved by surface modification of PS based membranes. Therefore, in this work, ultrafiltration membranes with increased HPCT were prepared using the enantiomeric tartaric acid (D-TA) and racemic tartaric acid (DL-TA). Phase inversion technique was used for the preparation of polyethylene glycol and TA blended PS membrane. Morphological analysis of the fabricated membranes was done by scanning electron microscope and atomic force microscopy. Bovine serum albumin (BSA) solution was taken for finding the permeation and rejection behavior of prepared membranes. Maximum BSA rejection was increased by 70.5% for the modified membrane.

• Bulletin of the Korean Chemical Society
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• v.32 no.9
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• pp.3382-3388
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• 2011

Reaction of barbituric acid (BA), 1,3-dimethyl barbituric acid (DMBA) and 2-thiobarbituric acid (TBA) with cyanogen bromide and aldehydes in the presence of L-(+)-tartaric acid afforded a new route for the synthesis of stable heterocyclic 5-aryl-1H,1'H-spiro[furo[2,3-d]pyrimidine-6,5'-pyrimidine]2,2',4,4',6'(3H,3'H,5H)-pentaones which is a dimeric form of barbiturate (uracil and thiouracil derivative). In the reaction of 1,3-diethyl thiobarbituric acid (DETBA) the Knoevenagel condensation and then Michael adducts were obtained under the same condition. Structure elucidation is carried out by $^1H$ NMR, $^{13}C$ NMR, FT-IR and Mass analyses. Mechanism of the formation is discussed.

• Journal of Sericultural and Entomological Science
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• v.38 no.2
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• pp.138-143
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• 1996

Cooking of tasar silk cocoon of Deba variety (A. mylitta D.) with tartaric acid has been optimized by using an orthogonal central composite design. Shell weight loss and silk filament recovery are influenced by duration of treatment and acid concentration. Mechanical properties do not change with the process parameters. Hardness of water does not affect significantly the recovery of silk filament.

• Membrane and Water Treatment
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• v.7 no.3
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• pp.257-275
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• 2016

The enantiomeric and racemic effects of tartaric acid (TA) on the properties of polysulfone (PSn) ultrafiltration membranes were studied in terms of morphology and hydrophilicity (HPCT) of membrane. Asymmetric membranes were prepared by direct blending of polyvinyl pyrrolidone (PVP) with D-TA and DL-TA in membrane casting solution. FTIR analysis was done for the confirmation of the reaction of PVP and TA in blended membranes and plain PSn membranes. Scanning electron microscope (SEM), field emission scanning electron microscope (FESEM) and atomic force microscopy (AFM) were used for analyzing the morphology and structure of the resulting membranes. The membranes were characterized in terms of pure water flux (PWF), hydraulic permeability and HPCT. PWF increased from $52L/m^2h$ to $79.9L/m^2h$ for plain and D-TA containing PSn membrane, respectively. Water contact angle also found to be decreased from $68^{\circ}$ to $55^{\circ}$. In Additionally, permeation and rejection behavior of prepared membranes was studied by bovine serum albumin (BSA) solution. A considerable increase in BSA flux (from $19.1L/m^2h$ for plain membrane to $32.1L/m^2h$ for D-TA containing membrane) was observed. FESEM images affirm that the pore size of the membranes decreases and the membrane permeability increases from 0.16 to 0.32 by the addition of D-TA in the membrane. D-TA increases the HPCT whereas; DL-TA decreases the HPCT of PSn membrane. PVP (average molecular weight of 40000 Da) with D-TA (1 wt%) gave best performance among all the membranes for each parameter.

• Natural Product Sciences
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• v.16 no.1
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• pp.6-9
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• 2010

In continuing our search for biologically active compounds from Korean Compositae medicinal plants, we investigated the constituents of the aerial parts of Lactuca indica L. and isolated a phenylpropanoid derivative from its MeOH extract. The chemical structure was characterized by spectroscopic methods, including 1D and 2D NMR to be di-E-caffeoyl-meso-tartaric acid (1). Compound 1 was isolated for the first time from this plant. In this paper, we suggest that the NMR assignment at C-2 of (+)-taraxafolin-B should be corrected. In the human HBV-transfected liver cell line HepG2.2.15, the compound 1 effectively reduced HBV DNA level in the release of mature HBV particles from HepG2.2.15 cultivation.

• Journal of Microbiology and Biotechnology
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• v.20 no.4
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• pp.659-665
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• 2010

A cis-epoxysuccinate hydrolase (CESH) from Bordetella sp. BK-52 was purified 51.4-fold with a yield of 27.1% using ammonium sulfate precipitation, ionic exchange, hydrophobic interaction, molecular sieve chromatography and an additional anion-exchange chromatography. The CESH was stable in a broad range of temperature (up to $50^{\circ}C$) and pH (4.0-10.0) with optima of $40^{\circ}C$ and pH 6.5, respectively. It could be partially inhibited by EDTA-$Na_2$, $Ag^+$, SDS, and DTT, and slightly enhanced by $Ba^{2+}$ and $Ca^{2+}$. The enzyme exhibited high stereospecificity in D(-)-tartaric acid (enantiomeric excess value higher than 99%) with $K_m$ and $V_max$ values of 18.67 mM and $94.34\;{\mu}M$/min/mg for disodium cis-epoxysuccinate, respectively. The Bordetella sp. BK-52 CESH gene, which contained 885 nucleotides (open reading frame) encoding 294 amino acids with a molecular mass of about 32 kDa, was successfully overexpressed in Escherichia coli using a T7/lac promoter vector and the enzyme activity was increased 42-times compared with the original strain. It may be an industrial biocatalyst for the preparation of D(-)-tartaric acid.

• Bulletin of the Korean Chemical Society
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• v.19 no.6
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• pp.680-685
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• 1998

Two kinds of new aliphatic diols were synthesized by the ring-opening reaction of lactide and glycolide with 1,4-butanediol, a difunctional initiator, in the presence of stannous octoate. The resulting aliphatic diols were melt-polymerized with D-tartaric acid at 150 ℃ to produce new crosslinkable polyesters. They were reacted with hexamethylene diisocyanate in THF at 65 ℃ in a teflon mold for 24 h to prepare sequentially ordered crosslinked polyesters (BD/LT/GL/D-tartarate). Degradation of the prepared yellow crosslinked films was carried out in a buffer solution in order to examine the effect of time, pH, temperature and crosslinking degree on their degradation rate and mechanism. The rate of degradation increased with an increase in pH and temperature, but it decreased with increasing degree of crosslinkage incorporated into the crosslinked polyesters. We also found that the crosslinked polymers were converted into the acidic compounds such as lactic, glycolic, and D-tartaric acids during the degradation.

• Korean Journal of Food Science and Technology
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• v.11 no.4
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• pp.278-282
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• 1979

Sugars and organic acids in Korean hot pepper fruit (C, annuum L.) according to its portions, pericarp, seeds and placenta, were determined by gas liquid chromatography (GLC). ${\alpha}-\;and\;{\beta}-fructoses,\;{\alpha}-\;and\;{\beta}-glucoses$, galactose, sucrose and maltose were identified. Major sugar in pericarp was fructose, while those in seeds and placenta were surose and fructose. Amount of free sugars in seeds was higher than that in pericarp or placenta. Succinic, fumaric, malic, tartaric, citric and quinic acids were found. Citric acid was a major organic acid found in pericarp and placenta. The amount of each identified organic acid, however, was similar in seeds. Quantity of total organic acids identified in pericarp or placenta was higher than that in seeds.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.3
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• pp.379-385
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• 2015

The nutritional components of astringent persimmons according to growing region (five different regions) and cultivar (Daebong and Bansi) were analyzed. The analyzed nutritional components were proximate compositions, insoluble and soluble dietary fibers, vitamin C, carotenes (${\beta}$-carotene and lycopene), free sugars (glucose, fructose, and sucrose), sugar alcohols (xylitol, sorbitol, and mannitol), minerals (Na, Mg, K, Ca, Mn, Fe, and Zn), organic acids (tartaric acid, malic acid, citric acid, and succinic acid), tannic acid, total phenolic compounds, and flavonoids. Daebong and Bansi, which are representative cultivars of astringent persimmons grown in Korea, exhibited significant differences in nutritional components. Insoluble dietary fibers, ${\beta}$-carotene, fructose, sucrose, mannitol, potassium, malic acid, succinic acid, and total phenolic compounds were present at higher levels in Daebong as compared to Bansi. On the other hand, Bansi was rich in moisture, crude protein, vitamin C, Ca, Mn, tartaric acid, and flavonoids. Nutritional components were highly influenced by growing region. Daebong grown in region A was greater in ${\beta}$-carotene, sorbitol, mannitol, zinc, and total phenolic compounds among the all other tested persimmons grown in five different regions. The crude protein, Na, Ca, Mn, tartaric acid, and flavonoids were highest in Bansi grown in E region.

• Korean Journal of Food Science and Technology
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• v.37 no.6
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• pp.912-917
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• 2005

Physicochemical components of dried green algae, Seaweed fulvescens (Capsosiphon fulvescens) with $96.02{\pm}0.02%$ moisture content, were investigated. Crude protein, crude lipid, ash and carbohydrate content of C. fulvescens were $31.76{\pm}0.26,\;1.01{\pm}0.21,\;13.58{\pm}0.62\;and\;53.65{\pm}0.73$, respectively. Predominant minerals were Na, Mg, Ca, K and P. Fe $(122.83{\pm}11.19mg/%)\;and\;Se\;(0.90{\pm}0.07mg%)$ contents in were higher than those of other seaweeds. Major free sugars were identified as fructose, glucose, sucrose, maltose and galactose. Organic acid including L-malic acid, citric acid, tartaric acid and d-malic acid were detected. Most abundant amino acids were glutamic acid, aspartic acid and alanine. Main fatty acids were palmitic acid, linolenic acid and stearidonic acid, with 58.37% polyenes.