• Journal of the Korean Wood Science and Technology
• /
• v.42 no.1
• /
• pp.68-77
• /
• 2014

A compound has been isolated from the methanol extract of Styrax japonica bark using conventional chromatographic methods including silica gel chromatography, TLC and HPLC. The molecular formula of Styraxlignolide F analyzed by spectrometric analyses using FAB-MS, NMR was found to be $C_{27}H_{34}O_{11}Na$. The cytotoxicity of the styralignolide F was showed 15.2% in $1.0mg/m{\ell}$ on human kidney cell (HEK 293). As anticancer activity of $CH_2Cl_2$ fraction, over 60% of AGS and MCF-7 cells were inhibited in concentration of $1.0mg/m{\ell}$. In the results of anticancer test using quantification of Bcl-2, $CH_2Cl_2$ fraction showed lower Bcl-2 and p53 expression than those of styraxlignolide F and other fractions. In apoptosis of human lung carcunoma cancer cell (A549), $CH_2Cl_2$ fraction showed the highest inhibition rate (46.9%) and styralignolide F was the next (43.5%). The $CH_2Cl_2$ fraction showed higher anti-cancer activities than isolated substance (styraxlignolide F), probably due to the crude extract showing synergic effects by other components.

• Journal of the Korean Society of Groundwater Environment
• /
• v.3 no.1
• /
• pp.37-49
• /
• 1996

The objectives of this study are to investigate the groundwater and surface water contamination, to interpret the attenuation mechanism of contaminant transport, and to find the appropriate contamination indicator. at the two big landfill sites : Nanjido Landfill and Hwasung Landfill. Leachate from the Nanjido, th, Hwasung and the Kimpo waste disposal sites is characterized by high temperature (31.7-40.1$^{\circ}C$), high electric conductivity (14,650-32,800 ${\mu}$S/cm), somewhat higher pH(7.58-8.45) and low Eh (-119.4-20.4 mV), and is enriched in both major (Na$^{＋}$, K$^{＋}$, Ca$^{2＋}$, Mg$^{2＋}$, HC $O_3$$^{－}$, Cl$^{－}$) and minor (Mn, Sr$^{2＋}$, Ba$^{2＋}$, Li$^{＋}$, F$^{－}$, Br$^{－}$) ions. Municipal solid waste leachate and industrial waste leachate are effectively discriminated by the content of S $O_4$$^{2－}$, Fe, and heavy metals. The attenuation mechanism of each component was assessed using the chemical analysis. Cl-normalizing process, WATEQ4F simulation, and preceding flownet analysis. Based on the calculation of Contamination Factor, K, Na, Ca, Mg, B, Zn, HC $O_3$, Cl, F, Br and TOC are effective contamination indicators in the Nanjido landfill site, and K, Na, Ca, Mg, B, S $O_4$, HC $O_3$, Cl, F, Br and TOC in the Habsburg landfill site Particularly, TOC is the best contamination indicator in landfill sites influenced by sea water.

• Journal of the Korean Society for Heat Treatment
• /
• v.28 no.3
• /
• pp.126-133
• /
• 2015

The aim of this study is to investigate the effect of solution treatment on the corrosion behavior of Mg-8%Al-(0-1)%Zn casting alloys in 1M NaCl aqueous solution. After the solution treatment, all alloys showed single ${\alpha}$-(Mg) phase microstructure by dissolution of ${\beta}(Mg_{17}Al_{12})$ phase into the ${\alpha}$-(Mg) matrix. The $H_2$ evolution volume decreased with an increase in Zn content, which indicates that the addition of Zn plays a beneficial role in decreasing corrosion rate of the Mg-Al-Zn alloy in solution-treated state. The microstructural evaluations on the corrosion products and corroded surfaces after the immersion test in 1 M NaCl solution revealed that the incorporation of more $Al_2O_3$ and ZnO into the corrosion product, by which the penetration of $Cl^-$ ions is impeded, are thought to be responsible for the better corrosion resistance in relation with the Zn addition.

• Journal of Marine Life Science
• /
• v.2 no.2
• /
• pp.49-55
• /
• 2017

Four chemical treatments with hydrogen peroxide (H₂O₂), copper sulfate (CuSO₄), potassium permanganate (KMnO₄) and chlorine (Cl₂) were applied to the effluent pond water of a hybrid striped bass saltwater recirculating aquaculture system to compare their oxidation power. Four chemicals were applied at concentrations of 0 (control), 1, 5, 10 and 20 mg/l. An additional concentration of 40 mg/l was included in the chlorine treatment. Water samples from four hybrid striped bass ponds were tested with KMnO₄ and Cl₂. H₂O₂ did not reduce any of BOD, COD and chlorophyll-a, and copper sulfate was only effective on chlorophyll-a for the effluent pond. Removal efficiencies for chlorophyll-a by copper sulfate were 19.2%, 37.5%, 54.2% and 74.1% dose-dependently. Potassium permanganate effectively removed the BOD, COD and chlorophyll-a. The COD removal rates in four fish ponds varied from 15.9% to 31.6% at the concentration of 10 mg/l. Interestingly, Cl₂ did not reduce the BOD and COD at all, but the BOD and COD instead increased drastically with increasing the Cl₂ concentration. The pond water with the highest initial BOD and COD values among the fish ponds tested increased by 350% in the BOD and 150% in the COD at 20 mg/l. Furthermore, Cl₂ did not significantly reduce any types of solid matter in this study, while KMnO₄ seemed to reduce some extent volatile dissolved solid in the fish pond.

• Journal of Bio-Environment Control
• /
• v.28 no.2
• /
• pp.166-171
• /
• 2019

This study was conducted to investigate the effect of gaseous chlorine dioxide ($ClO_2$) concentration and treatment method for maintaining marketability in strawberries 'Maehyang' for export. After harvesting strawberry colored with $60{\pm}5%$ of the skin, and the gaseous $ClO_2$ was applied as four treatments in the cold store set with $10^{\circ}C$ which were as follows: i) non-treatment (Control), ii) $0.2mg{\cdot}L^{-1}$ for 30 minutes, iii) $0.4mg{\cdot}L^{-1}$ for 30 minutes, and iv) continuously exposed at $0.4mg{\cdot}L^{-1}$ during the storage period. Weight loss, firmness, soluble solids content, color, incidence of gray mold, and quality grade of strawberries were investigated every 3 days during 16 days storage in cold store. The weight loss was consistently high at $0.2mg{\cdot}L^{-1}\;ClO_2$ treatment, and the weight loss was lower than other treatments when gaseous $ClO_2$ was continuously treated. Firmness was significantly higher at 0.2 and $0.4mg{\cdot}L^{-1}$ $ClO_2$ treatment on the 13th day of storage. Soluble solids content tended to below in continuous gaseous $ClO_2$ treatment. The colors showed no tendency as affected by concentrations and treatment methods of gaseous $ClO_2$. No gray mold was observed in the continuous gaseous $ClO_2$ treatment until the 13th day of storage. The quality grade was lower in gaseous $ClO_2$ treatment group than in the control. As a result, it was possible to decrease the weight loss and the incidence of gray mold by continuously treating the gaseous $ClO_2$ to strawberry 'Maehyang' for export during the storage period after harvest. However, further research is needed on method to maintain quality grades of fruits.

• Journal of Environmental Health Sciences
• /
• v.30 no.2
• /
• pp.161-166
• /
• 2004

The impact of dissolved wastewater constituents on the treatment of synthetic bisphenol A (BPA) solutions was investigated under a variety of reaction conditions. The laccase enzyme from Trametes vesicolor was used for the BPA treatment. The constituents studied included various inorganic salts, organic compounds and heavy metal ions. BPA degradation was inhibited by sulfate, thiosulfate, sulfide, nitrite, and cyanide ions at 25 mg/$\ell$, 100mg/$\ell$, 25 mg/$\ell$ 150 mg/$\ell$, and 2.5 mg/$\ell$, respectively. However, the inhibitive effects of sulfide and sulfite on BPA degradation were diminished by additional aeration to oxidize them. Formaldehyde significantly reduced the rate of BPA degradation at 1.0% among organic compounds studied. Among heavy metal ions tested, Fe(II) substantially suppressed BPA removal at 1 mM. MgCl$_2$ and CaCl$_2$ exhibited great inhibition of BPA degradation at 25mM.

• KSBB Journal
• /
• v.15 no.6
• /
• pp.664-669
• /
• 2000

Micellar aggregates are known to be useful for the selective isolation of biologically active materials such as amino acids, proteins, and enzymes from crude mixtures sparsely dispersed in water. In this study, the effects of pH, salt type and its concentration on the solubilization of $\alpha$-chymotrypsin into the organic micellar phase, which consisted of AOT (sodium 야(2-ethylhexy)sulfosuccinate) and iso-octane, were comprehensively examined. It was found that maximum extraction efficiency was attained at a pH below the isoelectric point of $\alpha$-chymotrypsin; at pH=5.0 for NaCl and KCl, and at pH=7.0 for $CaCl_2$and $MgCl_2$. In order to avoid complications stemming from the precipitationof protein at low pH interfaces, the protein concentrations in the organic and aqueous phases were directly measured. The size of the micelle water pool was estimated by measuring the molar ratio of the surfactant to the water, W(sub)o. The resulting values of W(sub)o were nearly constant at 30 and 19 for NaCl and KCl, respectively, and were independent of pH. The addition of 1:2 salts like $MgCl_2$and $CaCl_2$ led to much lower, but a constant value of, W(sub)o than the 1:1 salts.

• Proceedings of the Korean Institute of Resources Recycling Conference
• /
• 2003.10a
• /
• pp.122-128
• /
• 2003

To develop a Mg-Zeolite for simultaneous recovery of the N and the P from sewage water, the natural zeolite was treated with 20% $MgCl_2$ solution by changing the pH the temperature and the treating time of the solution. And the contents of Ca Fe Na K Mg of Mg-Zeolite were analyzed by ICP. The optimum treatment condition for Mg-Zeolite was induced to pH 7.0 $50^{\circ}C$ in 20% $MgCl_2$ solution and for 80min treatment. And the Na and the K ions in natural zeolite are significant factors for Mg exchange in the zeolite.

• Food Science and Preservation
• /
• v.7 no.3
• /
• pp.249-255
• /
• 2000

Soybean curd has been known as one of the most favorite traditional Korean foods as well as being high in protein. Each concentration of added natural materials soybean curds was chosen as 4% of carrot, 10% of cucumber, 1.0% of spinach and 0.05% of green tea powder. The yield of soybean curd containing natural materials was similar to that of non-containing curd. According to add GDL as coagulant, the yield of soybean curd containing natural materials was the highest. The turbidity of added natural material soybean curds was the highest coagulated with $CaCl_2$, but soybean curd containing green tea had the highest turbidity in the coagulated with GDL. In the chromaticity and texture properties of the additive natural materials in yhe soybean curd, the variety of additives had no effect. In the composition of natural materials, the carotenoid and chlorophyll content of soybean curds were high with $MgCl_2$ and $CaCl_2$ but polyphenol was high use of $CaSo_4$ and GDL.

• Biomolecules & Therapeutics
• /
• v.1 no.2
• /
• pp.137-142
• /
• 1993

The possible tumor-promoting activities of sodium chloride (NaCl) and dimethyl itaconate (DMI), one of the quinone reductase inducers, were examined on stomach of male Wistar rats treated with N-methyl-N'-nitro-N-nitrosoguanidine (MNNG). Administrations of NaCl and DMI after the initiation by MNNG resulted in various sized masses in the rat forestomach. Histopathologic studies showed that the combination of NaCl and DMI made an enhancing effect on the MNNG-induced carcinogenesis, resulting in papilloma in 5 weeks and squamous cell carcinoma in 20 weeks in submucosal area of forestomach. We also used an in vivo shortterm method for evaluating possible tumor-promoting activity with ornithine decarboxylase (ODC) as a marker. The markable inductions of the ODC activities by MNNG, NaCl, and DMI were found in the pyloric mucosa of rat stomach in time-dependent manners. A single administration of MNNG induced ODC activity up to 288 pmol $CO_2$/hr/mg protein at 24 hr after the administration. NaCl caused induction of ODC with a maximum of 179 pmol $CO_2$/hr/mg protein at 8 hr after the administration. ODC was induced up to 539 pmol $CO_2$/hr/mg protein at 16 hr after the administration of DMI. Additional treatment of NaCl and NaCl plus DMl caused 2 fold and 7 fold increases, respectively, in the ODC activity of the MNNG-alone group at 24 hr after the administration. These results suggest that NaCl and DMI have promoting activities in the rat gastric carcinogenesis initiated by MNNG.