• Microbiology and Biotechnology Letters
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• v.24 no.2
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• pp.222-226
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• 1996

The enzymatic synthesis of 3, 4-dihydroxyphenyl-L-alanine (L-DOPA) was examined for the effects of the reaction additives such as sodium borate, alcohol, and organic solvents. The enzyme used was tyrosine phenol-lyase of Citrobacter freundii KCTC 2006 produced in Escherichia coli. The amounts of tyrosine phenol-lyase and pyridoxal-5-phosphate were optimized to 2.0 units/ml and 0.1 mM, respectively, for the synthetic reaction. Sodium borate, a substance that forms a complex with pyrocatechol, reduced the enzyme deactivation by pyrocatechol although it seriously inhibited the enzyme activity. Among the organic solvents tested, dimethylsulfoxide, dimethylformamide, and alcohol increased the productivity of the L-DOPA synthesis. In a reaction system with 5% methanol, L-DOPA concentration increased up to 210 mM after 24 hours, and 77.1% of which was separated as precipitates. The L-DOPA was purified to 99.96% by solubilizing and recrystallyzing the precipitates.

• Journal of the Korean Wood Science and Technology
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• v.42 no.2
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• pp.157-162
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• 2014

This study was conducted to examine the functionality of the fire retardant treated wood. The hygroscopic property, leaching resistance, metal corrosive efficacy and gas toxicity of retardant treated wood were analyzed. Sodium silicate was penetrated to the wood for making fire retardant treated wood. The subsequent treatment agents such as boric acid, ammonium borate, di-ammonium phosphate were treated after sodium silicate treatment due to fixation. As results for the test, the leaching resist was improved by subsequent treatment. The fire retardant combination such as sodium silicate, boric acid and di-ammonium phosphate showed high hygroscopic property, metal corrosive efficacy. The gas toxicity was also satisfied KS standard.

• Bulletin of the Korean Chemical Society
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• v.2 no.1
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• pp.24-28
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• 1981

Theoretical studies of the sodium cation binding and the isotope hydration effects on the static model compound B-DNA have been qualitatively elucidated by using empirical potential energy functions. In the first place, the sodium cations bound to phosphate anions and their hydration scheme have been optimized and have given a reasonable agreement with other theoretical results and experimental studies. In the second stage, the isotope effect on the hydration through the substitution of $D_2O\;for\;H_2O$ has been carried out by the same procedure. The stabilization of B-DNA has been explained and compared in terms of the sodium cation binding to phosphate anions and its hydration in both cases of $H_2O\;and\;D_2O$.

• Korean Journal of Food Science and Technology
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• v.35 no.6
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• pp.1169-1173
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• 2003

Growth of a newly emerging pathogen, Arcobacter butzleri, in domestic raw meat was evaluated by various sanitizing agents. One percent of acetic acid, citric acid, lactic acid, and trisodium phosphate (TSP) added to the cell suspension of six A. butzleri strains inhibited their growth within ten minutes, and especially the lactic acid inhibited growth within five minutes. One percent of all the acids at the culture broth inhibited growth completely within one hr. 0.1% of the acids inhibited growth within 72 hr, whereas two percent of TSP had the same effect in one hr. Among the acids, lactic acid had the strongest inhibition activity. Hydrogen peroxide, sodium hypochlorite, and ethanol showed lower inhibiting activities than the above agents. While garlic extract and lactic acid bacteria culture also inhibited A. butzleri, onion extract did not. Therefore, food-borne poisoning of A. butzleri in raw meat could be prevented by organic acid and trisodium phosphate treatments.

• Journal of the Korean Wood Science and Technology
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• v.40 no.5
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• pp.335-342
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• 2012

To prepare the eco-friendly fire retardant wood, Japanese red pine (Pinus densiflora), Hemlock (Tsuga heterophylla), and Radiata pine (Pinus radiata) were treated with inorganic chemicals, such as sodium silicate, boric acid, ammonium phosphate, and ammonium borate. Different combination and concentration of those chemicals were impregnated by vacuum/pressure treatment methods. The electron-beam treatment was used to increase the chemical penetration into the wood. The fire performance of the fire retardant treated wood was investigated. The penetration of chemicals into the wood was enhanced after electron beam treatment. Ignition time of the treated wood was the most effectively retarded by sodium silicate, ammonium phosphate, and ammonium borate. The most effective chemical combination was found at 50% sodium silicate and 3% ammonium borate, which satisfied flammability criteria for a fire retardant material in the KS F ISO 5660-1 standards.

• Korean Journal of Soil Science and Fertilizer
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• v.48 no.5
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• pp.326-331
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• 2015

High salinity and sodicity of soils play a negative role in producing crops in reclaimed tidal lands. To evaluate the effects of soil ameliorants on salt removal in a highly saline and sodic soil of reclaimed tidal land, we conducted a column experiment with treating gypsum, compost, and phosphate at 0-2 cm depth and measured the salt concentration of leachate and soil. Electrical conductivity of leachate was $45-48dSm^{-1}$ at 1 pore volume (PV) of water and decreased to less than $3dSm^{-1}$ at 3 PV of water. Gypsum significantly decreased SAR (sodium adsorption ratio) of leachate below 3 at 3 PV of water and soil ESP (exchangeable sodium percentage) below 3% for the whole profile of soil column. Compost significantly decreased ESP of soil at 0-5 cm depth to 5% compared with the control (20%). However, compost affected little the composition of cations below a depth of 5 cm and in leachate compared with control treatment. It was concluded that gypsum was effective in ameliorating reclaimed tidal lands at and below a soil layer receiving gypsum while compost worked only at a soil layer where compost was treated.

• Journal of the Korean Ceramic Society
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• v.41 no.8
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• pp.610-617
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• 2004

For preparation $\alpha$-Al$_2$O$_3$ platelets having 20 $\mu$m in average diameter and 0.2∼0.3 $\mu$m in thickness, we have prepared aluminum hydroxides gel by using aluminum sulfate and sodium sulfate as starting materials. In this study, we investigated the effect of the amount of sodium phosphate on particle size, morphology and thickness of $\alpha$-Al$_2$O$_3$ platelets. When sodium phosphate was not added to aluminum hydroxides gel, most of $\alpha$-Al$_2$O$_3$ platelets had hexagonal shape but the thickness was over 1.0 $\mu$m, and this sample was not adequate for pearlescent pigment. On the other hand, introduction of sodium phosphate caused an increase of aspect ratio (particle diameter/thickness) with a decrease in $\alpha$-Al$_2$O$_3$ platelet thickness.

• 한국생물공학회:학술대회논문집
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• 2003.04a
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• pp.475-479
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• 2003

Glycosaminoglycans(GAGs) from sea squirt, Styela clava was extracted with sodium phosphate at $105^{\circ}C$ for 2 hr and deprotein with trichloroacetic acid or hydrochloride. This GAGs was mainly constituted of galactose, glucosamine, glucose, mannose and galactosamine, and was phenylalanine, threonine, glutamic acid and aspartic acid. Mineral contents was mainly constituted 3.0mg% sodium, 1.6mg% potassium and 1.2mg% phosphorus and heavy metal was not detected. At pharmaceutical and cosmetic code of GAGs, protein and sulfate contents should included each range $14.0{\sim}22.0%$, $35.0 {\sim}45.0%$. After 5.0% trichloroacetic acid(w/v) and 10.0% HCl(v/v) treatment, protein and sulfate contents of GAGs was contained each 35.1%, 35.4% and each 22.0%, 18.5%.

• Journal of the Korean Wood Science and Technology
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• v.33 no.4 s.132
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• pp.38-44
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• 2005

This study was carried out to investigate the combustion characteristics of flame retardant treated wood by water-soluble flame retardants which are made from mixture of aqueous solution of monoammonium phosphate, sodium borate and zinc borate. The combustion characteristics for flame retardant treated wood were carried out using thermal analysis (TGA, combustion heat) and flame retardant test (LOI, flame propagation). The results of thermal analysis and flame retardant test are as follows; 1) The sample treated by F4 showed excellent flame retardant effects in almost all of combustion characteristics. 2) From TGA curves, all the samples undergo pyrolysis and oxidation in two main discrete steps. 3) The effect of flame retardant for softwood is higher than those for hardwood, and the combustion heat has decreased with increase of the content of flame retardant. 4) LOI values are almost similar in flame retardant treated wood samples. The range of LOI is from 24 to 30. However, these values are much higher than LOI value of non-treated wood sample. 5) The blended aqueous solution had a final in the range of about pH 8.4, and a slight odor of ammonia.

• KSBB Journal
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• v.18 no.3
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• pp.180-185
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• 2003

Glycosaminoglycans (GAGS was extracted from sea squirt, Styela clava with sodium phosphate at 105$^{\circ}C$ for 2 hr and deproteinized with trichloroacetic acid or hydrochloride. The GAGs obtained from tunic consist 41.7% crude carbohydrates, 31.8% crude protein, and 31.2% sulfate. It was mainly constituted of galactose, glucosamine, glucose, mannose, and glacrosamine. The prominent amino acid were phenylalanine, threonine, glutamic acid, and aspartic acid. Mineral contents was mainly constituted 3.0 mg% sodium, 1.6 mg% potassium, and 1.2 mg% phosphorus. Trichloroacetic acid, hydrochloride and 5-sulfosalicylic acid were used for deprotein of the GAGs. Effective volume for deprotein of crude GAGs were 5.0% trichloroacetic acid (w/v) and 10.0% HCI (v/v) treatment. The deproteinized GAGs contained 35.1%, 35.4% of protein and 22.0%, 18.5% of sulfate, respectively.