• Journal of the Korean Institute of Telematics and Electronics
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• v.15 no.2
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• pp.19-21
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• 1978

The electrical drift mobility of charge carrier of Cholesteryl Benzoate was measured by Polarity inversion method in the temperature range 140~ 185$^{\circ}C$. with a view to revealing the mechanism of charge carrier transport. The electrical drift mobility of charge carrier of that increased from 2.5$\times$10-7$\textrm{cm}^2$/V.sec to 2.0$\times$10-6$\textrm{cm}^2$/v.sec as the temperature increased. As a result of the experiment, the mechanism of current transport is believed to be ionic mechanism.

• 한국생물공학회:학술대회논문집
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• 2000.04a
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• pp.434-437
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• 2000

Streptomyces setonii(ATCC 39116) is a thermophilic gram-positive soil bacteria which undergoes an ortho-cleavage pathway in the presence of phenol or benzoate as a sole carbon and energy source. The specific activities of catechol-1,2-dioxygenase in S. setonii, a key enzyme in ortho-cleavage pathway, were induced by various aromatic compounds such as benzoate, phenol, m-hy-benzoate, p-hy-benzoate, catechol, o-cresol, m-cresol, p-cresol, benzene, toluene, ethyl-benzene, 2-chloro-phenol, and 4-chloro-phenol, among which the phenol showed the highest inducibility in the presence of 0.01% glucose. More than 0.1% glucose dramatically reduced the specific activities of catechol-1,2-dioxygenase induced by most of the single aromatic compounds tested.

• Journal of Microbiology and Biotechnology
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• v.10 no.1
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• pp.111-114
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• 2000

Streptomyces are widespread in nature and play a very important role in the biosynthesis as well as biodegradation of natural and unnatural aromatic compounds. Both qualitatively and quantitatively through TLC and UV spectrophotometric assays, it was observed that the thermophilic soil bacteria S. setonii (ATCC 39116), which can utilize a benzoate as a sole carbon and energy source in a minimal liquid culture, was not very sensitive to the benzoate concentation and to the culture conditions such as the pH and temperature. The in vitro conversion of a catechol to a cis, cis-muconic acid by a crude S. setonii lysate implies that the aromatic ring cleavage by S. setonii is initiated by a thermostable catechol-1,2-dioxygenase, the key enzyme in the ortho-cleavage pathway of aromatic compound biodegradation. Unlike non-degrading S. lividans, S.setonii was also highly resistant to other similar hazardous aromatic compounds, exhibiting almost no adverse effect on its growth in a complex liquid culture.

• Journal of Food Hygiene and Safety
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• v.7 no.1
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• pp.49-52
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• 1992

A Liquid Chromatogaphic Method was applied to analyze the following nine preservatives used for foods simultaneously; propionic acid, sorbic acid, benzoic acid, dehydroacetic acid, ethyl p-hydroxy benzoate, propyl p-hydroxy benzoate, i-butyl p-hydroxy benzoate, butyl p-hydroxy benzoate, ethyl salycilate. A cosmosil $5C_{I8}$ was used and 1% phosphoric acid-acetonitrile (60 : 40) was used as the mobile phase. Pretreatment of the food sample with steam distillation improved the resolution of peaks at 220 nm.

• Bulletin of the Korean Chemical Society
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• v.31 no.5
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• pp.1424-1426
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• 2010

• Journal of Microbiology
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• v.44 no.6
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• pp.632-640
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• 2006

In this study, the biodegradative activities of monocyclic aromatic compounds were determined from the multi-drug resistant (MDR) Acinetobacter baumannii, which were studied in the form of clinical isolates from a hospital in Korea. These bacteria were capable of biodegrading monocyclic aromatic compounds, such as benzoate and p-hydroxybenzoate. In order to determine which pathways are available for biodegradation in these stains, we conducted proteome analyses of benzoate, and p-hydroxybenzoate-cultured A. baumannii DU202, using 2-DE/MS analysis. As genome DB of A. baumannii was not yet available, MS/MS analysis or de novo sequencing methods were employed in the identification of induced proteins. Benzoate branch enzymes [catechol 1,2-dioxygenase (CatA) and benzoate dioxygenase $\alpha$ subunit (BenA)] of the $\beta$-ketoadipate pathway were identified under benzoate culture condition and p-hydroxybenzoate branch enzymes [protocatechuate 3,4-dioxygenas $\alpha$ subunit (PcaG) and 3-carboxy-cis,cis-muconate cycloisomerase (PcaR)] of the $\beta$-ketoadipate pathway were identified under p-hydroxybenzoate culture condition, respectively, thereby suggesting that strain DU202 utilized the $\beta$-ketoadipate pathway for the biodegradation of monocyclic aromatic compounds. The sequence analysis of two purified dioxygenases (CatA and PcaGH) indicated that CatA is closely associated with the CatA of Acinetobacter radiresistance, but PcaGH is only moderately associated with the PcaGH of Acinetobacter sp. ADPI. Interestingly, the fused form of PcaD and PcaC, carboxymuconolactone decarboxylase (PcaCD), was detected on benzoate-cultured A. baumannii DU202. These results indicate that A. baumannii DU202 exploits a different $\beta$-ketoadipate pathway from other Acinetobacter species.

• Korean Journal of Environmental Agriculture
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• v.16 no.1
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• pp.14-18
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• 1997

The objective of this research was to increase phytoprotective effects by combined treatment of uniconazole and free radical scavengers such as ascorbic acid or sodium benzoate on $SO_2$ injury in P. occidentalis. The plant injury, chlorophyll content and enzyme activity of superoxide dismutase(SOD) and peroxidase(POD) affected by combined treatment were also investigated. The phytoprotective role of uniconazole was nullified by spray of Diethyldithiocarbamate(DDTC) resulting in the decrease of SOD and POD activities. Free radical scavengers, sodium benzoate and ascorbic acid, did not affect SOD and POD activity, but significantly inhibited the development of visible injury, degradation of chlorophyll, and SOD and POD activity in leaves exposed to $SO_2$. The spray of ascorbic acid decreased plant susceptibility to $SO_2$ induced by DDTC application. These results indicate that uniconazole application increase SOD activity that play a role of antioxidant in plant body, but sodium benzoate and ascorbic acid do not affect enzyme activities of SOD or POD.

• Journal of Microbiology and Biotechnology
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• v.14 no.3
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• pp.483-489
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• 2004

Pseudomonas sp. S-47 is a bacterium capable of degrading benzoate as well as 4-chlorobenzoate (4CBA). Benzoate and 4CBA are known to be degraded via a meta-cleavage pathway characterized by a series of enzymes encoded by xyl genes. The meta-cleavage pathway operon in Pseudomonas sp. S-47 encodes a set of enzymes which transform benzoate and 4CBA into TCA cycle intermediates via the meta-cleavage of (4-chloro )catechol to produce pyruvate and acetyl-CoA. In the current study, the meta-pathway gene cluster was cloned from the chromosomal DNA of S-47 strain to obtain pCS1, which included the degradation activities for 4CBA and catechol. The genetic organization of the operon was then examined by cloning the meta-pathway genes into a pBluescript SKII(+) vector. As such, the meta-pathway operon from Pseudomonas sp. S-47 was found to contain 13 genes in the order of xylXYZLTEGFlQKIH. The two regulatory genes, xylS and xylR, that control the expression of the meta-pathway operon, were located adjacently downstream of the meta-pathway operon. The xyl genes from strain S-47 exhibited a high nucleoside sequence homology to those from Pseudomonas putida mt-2, except for the xylJQK genes, which were more homologous to the corresponding three genes from P. stutzeri AN10. One open reading frame was found between the xylH and xylS genes, which may playa role of a transposase. Accordingly, the current results suggest that the xyl gene cluster in Pseudomonas sp. S-47 responsible for the complete degradation of benzoate was recombined with the corresponding genes from P. putida mt-2 and P. stutzeri AN10.

• The Korean Journal of Pesticide Science
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• v.6 no.4
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• pp.244-249
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• 2002

This study was carried out to investigate the toxicities of 22 insecticides to Dichromothrips smithi. Insecticidal activity was evaluated by testing systemic action and residual effect in laboratory. All insecticides used in this study did not affect on the egg of D. smithi, although organophosphates such as fenitrothion, fenthion, methidathion, phenthoate, and phenthoate+ethofenprox suppressed the egg hatchability completely. On D. smithi larva fenitrothion, fenthion, methidathion, phenthoate, ethofenprox, thiamethoxam, abamectin, chlorfenapyr, emamectin benzoate, fipronil, spinosad, and phenthoate+ethofenprox showed 100% insecticidal activity. On D. smithi adult fenitrothion, fenthion, methidathion, phenthoate, ethofenprox, abamectin, emamectin benzoate, fipronil, spinosad, and phenthoate+ethofenprox showed 100% insecticidal activity. Root-uptake systemic effects of phenthoate on the larva of D. smithi was 43.3%. Whereas, systemic effect of other insecticides was less than 20%. Insecticide with more than 80% residual effect for 7 days after treatment were fenitrothion, fenthion, methidathion, phenthoate, ethofenprox, emamectin benzoate, fipronil, spinosad, and phenthoate.

• Journal of the Korean Chemical Society
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• v.36 no.2
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• pp.212-217
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• 1992

The thermodynamic parameters for the formation of gadolinium benzoate have been determined in the ionic medium of 0.1 M $NaClO_4$ at $25^{\circ}C$ in aqueous solution. The thermodynamic results indicate that the complex is stabilized by the excess entropy effect caused by the dehydration of reacting ions. The especially high stability of Gd(III)-benzoate compared to the monodentate ligand complexes might be ascribed to the conjugation effect of the benzene ring in the benzoate ligand. IR spectra show that benzoate anion acts as a bidentate ligand toward $Gd^{3+}$ to form a chelate ring in solid state. Magnetic susceptibility data of the compound were also obtained and well described by Curie-Weiss law in the temperature range 80${\sim}$300K.