• YAKHAK HOEJI
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• v.33 no.2
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• pp.118-123
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• 1989

A new polyacetylene compound which has strong cytotoxic activity against L1210 cell, was isolated from Korean ginseng roots. The structure was determined to be heptadeca-1-ene-4,6-diyne-3,9-diol-10-acetate (10-acetyl panaxytriol, $ED_{50}\;=\;1.2\;{\mu}g/ml$). The cytotoxicities of this compound and acetyl panaxydol lower than their starting substances, panaxytriol and panaxydol. The presence of one for the decreases in the cytotoxicities.

• Journal of Microbiology and Biotechnology
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• v.18 no.2
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• pp.334-337
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• 2008

A tightly regulated gene expression system composed of a single-copy target gene under the control of a lac promoter derivative and lacI gene in a multicopy plasmid is proposed, and its ability to control the flux of a metabolic pathway is demonstrated. A model system to control the flux of acetyl-CoA to acetyl phosphate was constructed by integrating pta, a gene encoding phosphotransacetylase, under a tac promoter into the chromosome of E. coli with a pta-negative background and transforming a multicopy plasmid containing the $lacI^Q$ gene into the strain. The production rate of acetate was shown to be tightly controlled when varying the concentration of the inducer (IPTG) in he model system.

• Archives of Pharmacal Research
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• v.8 no.4
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• pp.213-220
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• 1985

From olibanum, acetylboswellic acid (I) and boswellic acid (II) were isolated as mixed crystals of $\alpha$-and $\alpha$-forms in the ratio of 1 to 2 and 1 to 4, respectively. And acetyl-11-keto$\beta$-boswellic acid (III) and 11-keto-$\beta$-boswellic acid (IV) were also isolated and their $\alpha$-forms were not found in olibanum by GC/selected ion monitoring MS technique. Contents of four compounds were determined.

• YAKHAK HOEJI
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• v.34 no.1
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• pp.15-21
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• 1990

-4,9-dione derivatives were prepared from $2-chloro-3-({\alpha}-accetyl-{\alpha}-ethoxycarbonyl-methyl)-1,4-naphthoquinone$ and 2-chloro-3-N-phenylamino-1,4-naphthoquinone. $2-Chloro-3-({\alpha}-acetyl-{\alpha}-ethoxycarbonyl-methyl)-1,4-naphthoquinone$ was reacted with amines to give $2-amino-3-({\alpha}-acetyl-{\alpha}-ethoxycarbonyl-methyl)-1,4-naphthoquinone$ derivatives. Subsequent treatment of $2-amino-3-({\alpha}-acetyl-{\alpha}-ethoxycarbonyl-methyl)-1,4-naphthoquinone$ with sodium ethoxide gave -4,9-dione derivatives. When 2-chloro-3-N-phenylamino-1,4-naphthoquinone reacted with sodium ${\alpha}-cyano$ ethyl acetate, 2-amino-3-ethoxycarbonyl-N-phenyl--4,9-dione was obtained. However, with sodium diethyl malonate, not -4,9-dione but 2-chloro-3-bis-(methoxycarbonyl)-methyl-2H-3-N-phenylamino-1,4-naphthoquinone was obtained.

• Journal of Microbiology and Biotechnology
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• v.30 no.2
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• pp.155-162
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• 2020

Acetyl xylan esterase (AXE; E.C. 3.1.1.72) is one of the accessory enzymes for xylan degradation, which can remove the terminal acetate residues from xylan polymers. In this study, two genes encoding putative AXEs (LaAXE and BhAXE) were cloned from Lactobacillus antri DSM 16041 and Bacillus halodurans C-125, and constitutively expressed in Escherichia coli. They possess considerable activities towards various substrates such as p-nitrophenyl acetate, 4-methylumbelliferyl acetate, glucose pentaacetate, and 7-amino cephalosporanic acid. LaAXE and BhAXE showed the highest activities at pH 7.0 and 8.0 at 50℃, respectively. These enzymes are AXE members of carbohydrate esterase (CE) family 7 with the cephalosporine-C deacetylase activity for the production of antibiotics precursors. The simultaneous treatment of LaAXE with Thermotoga neapolitana β-xylanase showed 1.44-fold higher synergistic degradation of beechwood xylan than the single treatment of xylanase, whereas BhAXE showed no significant synergism. It was suggested that LaAXE can deacetylate beechwood xylan and enhance the successive accessibility of xylanase towards the resulting substrates. The novel LaAXE originated from a lactic acid bacterium will be utilized for the enzymatic production of D-xylose and xylooligosaccharides.

• 한국생물공학회:학술대회논문집
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• 2001.11a
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• pp.370-373
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• 2001

Experiments were carried out to develop of mutant strain from Pichia ciferrii ATCC 14091 and investigate the effect of sodium acetate on the production of tetraacetylphytosphingosine (TAPS). A high-TAPS producing mutant was simply selected by staining with sudan black B and colony shape after the treatment of UV and NTG. Sodium acetate enhanced the TAPS production.

• Textile Coloration and Finishing
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• v.13 no.1
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• pp.9-17
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• 2001

The purpose of this study is to present basic data for the enzymatic modification of acetate fabrics. The weight loss and rate of weight loss of acetate fabrics increased with increasing NaOH concentration and treating time. Acetyl value decreased as the weight loss became higher. The weight loss of alkaline-treated acetate fabrics were directly proportional to the concentration and treating time of cellulase. The optimum temperature and pH in cellulase treatment were $55^\circ{C}$ and pH 3.5. The surface shape revealed that density of fiber decreased by alkaline-treatment. With the treating time of cellulase, fibrillation occurred. In case of higher weight loss in alkaline treatment, fibril is removed after 180 min. The tensile strength decreased by alkaline and cellulase treatment. Especially, in case of higher weight loss of alkaline treatment, tensile strength decreased suddenly. Alkaline treatment increased the drapability of acetates, while cellulase treatment increased it initially but decreased gradually with treatment time. The dyeability after alkaline treatment was improved for reactive dye, but deteriorated for disperse dye. The cellulase treatment of acetate lowered the dyeability for both types of dyes.

• The Korean Journal of Food And Nutrition
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• v.6 no.3
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• pp.169-177
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• 1993

The conversion of glutamate by glutamine synthetase Is the endergonic reaction that demands ATP as its energy source. In order to supply efficiently ATP that is demanded in the conversion of glutamate to glutamine, the ATP- generating system by acetate kinase partially purified from Escherichia coli K-12 was coupled with glutamine synthetase partially purified 5. coli K-12 Pgln6. The optinum conditions of the coupled reaction were investigated. As the result, the highest conversion of glutamate to glutamine was shown In the reaction mixture containing 100mM glutamate, 100mM NHtCl, 50M acetyl phosphate, 5mM ADP, 40M MgCl2, 300mM potassium phosphate buffer (pH 7.5), 5mM MnCl2, Under this condition, the most effective concentrations of enzyme were 70unit/ml glutamine synthetase and 99unit/ml acetate kinase. Under the optinum conditions, 98% of 100mM glutamate was converted to glutamine within 6 hours.

• Archives of Pharmacal Research
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• v.21 no.2
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• pp.217-222
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• 1998

A stereospecific HPLC method has been developed for the resolution of the enantiomers of salbutamol in human urine. After solid-phase extraction and derivatization with 2,3,4,6-tetra-O-acetyl-$\beta$-D-glucopyranosyl isothiocyanate, the diastereomeric derivatives were resolved (Rs=1.83) on $5{\mu}m$ octadecylsilan column using 35% acetonitrile in 0.05M ammonium acetate buffer (pH=6) as a mobile phase with electrochemical detection. The diastereomeric derivatives were formed within 30 min. The detection limit of each enantiomer was 20 ng/ml (S/N=3).

• Investigative Magnetic Resonance Imaging
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• v.7 no.1
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• pp.31-38
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• 2003

Purpose : To analyze the serial changes of proton magnetic resonance (MR) spectra in the abscess and to determine the effect of the antibiotic treatment on the metabolite patterns. Materials and Methods : MR imaging and MR spectroscopy of an experimentally induced abscess were performed sequentially for four weeks at interval of one week in both the control group (n=5) and the antibiotic treatment group (n=5). On MR imaging, the shape and the size of the abscess were analyzed. On MR spectroscopy, the resonance peaks of metabolites were assigned on the basis of reported peaks in the literature. The metabolite ratios measured by using N-acetyl alanine as an external reference and by using lipid as an internal reference were compared in both the control and treatment g roups. Results : The abscesses were seen as cystic masses on MR imaging. On MR spectroscopy, the variable peaks of acetate, succinate and various amino acids, which are the metabolites of infection, were identified in the control and antibiotic treatment groups. The most frequent peak was that of acetate at 1.92ppm (70%). Both the peak ratios of acetate to lipid and acetate to external reference tended to decrease in the treatment group while the ratios did not change significantly in the control group. Conclusion : MR spectroscopy is useful not only for the diagnosis of abscess but also for monitoring the evolution of the abscess by using the acetate peak.