• Journal of Food Hygiene and Safety
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• v.22 no.4
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• pp.248-256
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• 2007

In this study, the competitive polymerase chain reaction (cPCR) was used to develop a direct enumeration method of Salmonella spp. in pork meat. After comparing three DNA extraction methods, the modified guanidine thiocyanate-phenol-chloroform method was chosen for Salmonella DNA extraction in artificially inoculated pork meat. The previously reported 284-bp invA gene (Rahn et al. Mol. Cell. Probes 1992) was tested for specificity, and 57 Salmonella strains and 24 non-Salmonella strains were evaluated. All Salmonella strains tested were invA positive, and all non-Salmonella strains produced no false positive amplification products. The detection limit achieved was as low as 1,460 colony-forming units (cfu) per 0.1g of pork meat. For cPCR, the invA gene, which features a 82 bp-deletion, was cloned in the pGEM-4Z vector. A known amount of competitor DNA, which has the same primer binding sites, was co-amplified with Salmonella chromosomal DNA from the artificially inoculated pork meat. The cell-number determined by cPCR was approximately equal to the cfu from the most probable number (MPN) method. Finally, the whole procedure took only 5 hr.

• Journal of Life Science
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• v.14 no.5
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• pp.863-867
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• 2004

Antioxidative activities of pine (Pinus denstifora) needle extracts were tested in vitro experimental models. The concentration of total polyphenolic compound of water extracts from pine needle was 1.61 %. In DPPH ($\alpha$, $\alpha'$-diphenyl-$\beta$-picrylhydrazyl) method, the electron donating activity of 0.1 % water extracts from pine needle was as high as BHT (0.05%, w/v). The antioxidative activity was measured by inhibition against lipid peroxidation of rat liver microsome, and this activity was shown in the following: 67.7% at 0.1% concentration >63.1% at 0.05% concentration > 28.2% at 0.01% concentration. In antioxidative activity determined by thiocyanate method against lipid peroxidation using linoleic acid, the antioxidative activities at all concentration of 0.01 %, 0.05% and 0.1 % were much higher than control during 7 days. In TBA method, the antioxidative activity was increased with increasing concentration until 6 days. These results support that water extracts from pine needle contain antioxidative compounds.

• Asian-Australasian Journal of Animal Sciences
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• v.20 no.9
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• pp.1424-1432
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• 2007

Two male, rumen fistulated crossbred Brahman-Thai native beef cattle (body weight = $400{\pm}50$ kg), fed on rice straw as a source of roughage, were used as rumen fluid sources. The treatments were $2{\times}3$ factorial arrangements; two roughages (fresh cassava foliage and cassava hay) and three sulfur levels (elemental sulfur) at 0.2 (control), 0.5 and 1% of DM, respectively. The experiment revealed that the rates (c) of gas production, ammonia-nitrogen concentration, true digestibility, total concentration or molar proportions of VFA and microbial biomass were not significantly different between cassava hay and fresh cassava foliage. However, all parameters for cassava hay were higher than for fresh cassava foliage. The supplementation of 0.5% sulfur to fresh cassava foliage resulted in a significant increase in the rate of gas production, true digestibility, total concentration of VFA, microbial biomass, rate of HCN disappearance, thiocyanate appearance and cyanide percentage conversion into thiocyanate. However, there were no effects of sulfur supplementation at 0.2, 0.5 and 1% to cassava hay. The finding suggests the utilization of cassava foliage for rumen microorganisms in terms of fermentation and HCN detoxification could be improved by sulfur supplementation of 0.5% of DM.

• KSBB Journal
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• v.15 no.2
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• pp.150-155
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• 2000

Antioxidative activity of c비ture of Streptomyces sp. BH-405 was investigated. After removal of pellets of Streptomyces sp. B BH-405, antioxidative substances were is미ated and suc$\infty$sively purified from culture of Streptomyces sp. BH-405 by by thin | layer chromatography $\pi$LC) or silica gel column chromatography. The fraction 3 obtained from ethylether fractionation of the C culture appeared highest level of anti oxidative activity as determined by thiocyanate method. Band 2 obtained by further P purification of this fraction showed higher anti oxidation level than that of same concentration of dl- $\alpha$ -tocopherol, butylated h hydroxy anisole (BHA). The band 2 showed higher rate of 1, 1.diphenyl 2-picrylhydrazyl (DPPH) decolorization than dl-$\alpha$-tocopherol. In the rat liver microsomes, band 2 rapidly inhibited lipid peroxidation which was initiated enzymatically by r reduced nicotinamide adenine dinucleotide phosphate (NADPH) or non-enzymatically by Fenton’s reagent. Band 2 inhibited on | lipid peroxidation of mitochondria or the linoleic acid hydro peroxide induced peroxidation system. It is concluded that band 2 obtained by fractionation of Streptomyces sp. BH-405 cultivation contained antioxidants with the capacity to inhibit oxidative m modification.

• Journal of the Korean Chemical Society
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• v.33 no.6
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• pp.651-656
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• 1989

The catalytic effects of several phase-transfer catalysts (PTC) on the liquid-liquid heterogeneous nucleophilic displacement reaction of thiocyanate on benzyl chloride have been determined. Reactions followed a pseudo-first order dependency on the benzyl chloride concentration and the observed rate constant $(k_{obsd})$ were linearly related to the concentration of catalyst and varied with variables such as reaction temperature and solvent. The sequences of catalytic activity of the displacement were $NH_4Cl$ < BTMAC < 18-crown-6 < BTEAC < PEG < TBAC < CTMAB. Enthalpies and entropies of activation associated with the displacement were 15∼20 Kcal$mo^{l-1}$, -12∼-29 eu. respectively and the reaction occurs in the interphase comprising of microemulsion.

• Applied Biological Chemistry
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• v.45 no.3
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• pp.157-161
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• 2002

New 2-benzoylimino-1,3-oxathile derivatives 3 were synthesized and tested their fungicidal activities for the development of new agrochemical fungicide. Reaction of ${\gamma}-chloro-{\beta}-keto$ anilide derivative 5 with potassium thiocyanate followed by the treatment of acid catalyst gave cyclyzed 2-imino-1,3-oxathiole 3. New compound 3 reacted with benzoyl· chlorides to afford the corresponding 2-benzoylimino-1,3-oxathiole derivatives 7. Antifungal screening (in vivo) of the synthesized compounds against typical plant diseases, which include rice blast, rice sheath blight, cucumber gray mold, tomato late blight, wheat leaf rust, and barley powdery mildew, was carried out. No significant fungicidal activities were shown of the synthesized compounds at 100 mg/l.

• Journal of the Korean Chemical Society
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• v.20 no.4
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• pp.280-289
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• 1976

The silver selenide electrode has been prepared and its properties as an indicating electrode for silver ion have been investigated. Epoxy resin was used as a filler of silver selenide electrode. Silver metal plate was directly connected with the membrane of the electrode and the silver paste was used as its binder. The sintered electrode was more sensitive and stable than the pressed electrode, and the silver selenide electrode more sensitive than the silver sulfide electrode to silver ion. The linear relationship between the electrode potential and logarithmic concentration of silver ion has been observed down to 10-6 M for the electrode. Several heavy metal ions except mercuric ion did not interfere this linearity, but halide, cyanide, and thiocyanate ions did intensively interfere owing to the formation of silver compounds and complexes. This electrode has been applied to the potentiometric titration for determining halide ion. It is concluded that interferences from ,$CN^-, SCN^-, S^-, I^-, Br^-, Cl^- and Hg^{2+}$ ions are detrimental to the practical use of the electrodes for measuring pAg.

• Bulletin of the Korean Chemical Society
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• v.31 no.12
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• pp.3617-3622
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• 2010

The reaction of stoichiometric amount of $FeCl_2{\cdot}4H_2O$, (2-pyridylmethyl, 3-pyridylmethyl)amine (2,3-pyma) and sodium azide/sodium thiocyanate in methanol under aerobic conditions affords the dinuclear Fe(III) complexes, [(2,3-pyma) $(N_3)_2Fe({\mu}-OCH_3)_2Fe(N_3)_2$(2,3-pyma)]${\cdot}CH_3OH$ (1) and [(2,3-pyma)$(NCS)_2Fe({\mu}-OCH_3)_2Fe(NCS)_2$(2,3-pyma)] (2) in good yield. Two bis-methoxy-bridged diiron(III) complexes are isolated and characterized. The coordination geometries around iron(III) ions in 1 and 2 are the same tetragonally distorted octahedron. The iron(III) ions are coordinated by two nitrogens of a 2,3-pyma, two nitrogens of two azide/thiocyanate ions, and two oxygens of two methoxy groups. Both compounds are isomorphous. The structures of 1 and 2 display the C-$H{\cdots}\pi$ and/or $\pi-\pi$ stacking interactions as well as hydrogen bonding interactions, respectively. Compounds 1 and 2 show significant antiferromagnetic couplings through the bridged methoxy groups between the iron(III) ions in the temperature range from 5 to 300 K ($H=-2JS_1{\cdot}S_2$, J=-19.1 and $-13.9\;cm^{-1}$ for 1 and 2).

• Journal of the Korean Chemical Society
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• v.31 no.6
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• pp.527-533
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• 1987

Kinetic studies on the complexing of aquamolybdenum(Ⅳ) trimer with thiocyanate have been carried out using the spectrophotometric method. The observed rate constant, $k_{obsd}$ is given by $k_{obsd}\;=\;{k_O + k_H[H^+]^2}(SCN^-) + k_r$. At 25$^{\circ}$C and ionic strength of 2.30 the values of $k_f$ and $k_r$ are $(3.78 {\pm} 0.61) {\times} 10^{-4}M^{-1}s^{-1}$ and $(6.93 {\pm} 2.39) {\times} 10^{-4}s^{-1}$, respectively. Activation parameters are ${\Delta}H^* = 50.71{\pm}6.91 kJmol^{-1}$ and ${\Delta}S^* = -121.65JK^{-1}mol^{-1}$. The mechanism is proposed and discussed.

• Journal of the Korean Chemical Society
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• v.5 no.1
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• pp.42-47
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• 1961

A titration of a small amount of iron with standard potassium ferrocyanide using potassium thiocyanate as indicator has been studied. A sample solution containing $0.1{\sim}1.0$ mg. $Fe^{3+}$ in 60 ml. is pipeted into 100 ml. Erlenmyer flask and the pH of the solution is adjusted to $1.5{\sim}3.0$ with 0.1 N or 1 N $HNO_3$ and $NH_4OH.$ To this solution one ml. of 1 M KCNS solution as indicator is added. The solution colored by iron thiocyanate complex is titrated with 1/200 M or 1/400 M standard solution of potassium ferrocyanide from a 5 ml. micro-buret. Near the end point, when the color of sample changes from deep red to green, about 20 ml. of ether is added and shake the flask vigorously. The red color is extracted to the ether layer. To settle the ether layer a few drops of ethanol is added and then standard solution is added dropwise and shake vigorously. The end point is reached when the color of the ether layer disappears owing to the quantitative formation of $Fe_4[Fe(CN)_6]_3.$ In this titration, 0.lmg. of $Fe^{3+}$ can be determined within 1.0% of titration error, provided the following optimum conditions, i.e., pH $1.5{\sim}3.0$, final concentration of KCNS indicator; $0.01{\sim}0.02M$, at room temperature. The titration found to be interfered by the presence of slightly soluble salts, stable complex forming ions and the ions which would be reduced by ferrocyanide or oxidized by ferric ion.