• Journal of Microbiology and Biotechnology
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• v.1 no.2
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• pp.102-110
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• 1991

Alkalophilic Bacillus sp. YJ-451, which was isolated from soil at several area in Korea, produced a novel type of bacteriolytic enzyme (cell wall peptidoglycan hydrolase) extracellulary. The cell wall hydrolytic activity was identified as a clear zone on sodium dodecyl sulfate polyacrylamide gel electrophoresis containing 0.2% (w/v) cell wall of Bacillus sp. as substrate. This enzyme was successively purified 66 fold with 3.2% yield in culture broth by ammonium sulfate precipitation, CM-cellulose column chromatography, and gel filtration, followed by hydroxylapatite column chromatography. The molecular weight of the purified enzyme was estimated to be 27,000 by sodium dodecyl sulfate polyacrylamide gel electrophoresis and gel filtration column chromatography. The optimum pH and temperature for the activity of the enzyme were pH 10.0 and $50^{\circ}C$, respectively. The enzyme was stable between pH 5.0 and 10.0 and up to $40^{\circ}C$. Among the microorganisms used in this experiment the enzyme was active against most of gram negative strains and the genus Bacillus such as B. megaterium, B. licheniformis, B. circulans, B. pumilus, B. macerans, B. polymyxa. The release of dinitrophenylglutamic acid but not reducing group from cell wall peptidoglycan digested by the enzyme suggested that the enzyme is a kind of peptidase which hydrolyzes the peptide bond at the amino group of D-glutamic acid in the peptidoglycan.

• KSBB Journal
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• v.18 no.6
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• pp.443-447
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• 2003

The microorganism was isolated from the night soil treatment plant for the removal of sulfur compounds. The growth conditions of the sulfur-oxidizing bacteria were investigated and the isolate characterized as Thiobacillus noveilus SRM. The optimal pH of Thiobacillus novellus SRM on cell growth was pH 7.0 and the optimal temperature was 30$^{\circ}C$ and the optimal air flow rate was 1 vvm, respectively. As a results of cell growth from the Monod plot, the specific growth rate was 0.032 hr$\^$-l/, $V_{max}$ was 1.43 hr$\^$-l/ and $K_{m}$ was 0.32, respectively. The thiosulfate oxidation by Thiobacillus novellus SRM was made of sulfate ion. The sulfate ion reduced pH and decreased cell growth.

• Journal of Soil and Groundwater Environment
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• v.16 no.5
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• pp.90-96
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• 2011

Simultaneous removal of heavy metals (Cd, Pb) and diesel-fuel from a soil column was evaluated by respectively flushing with sodium dodecyl sulfate (SDS) solution, mixture of SDS and sodium iodide (SDS + NaI), and surfactant foam (SDS + NaI foam). First, this study evaluated these flushing methods to the heavy metals only-contaminated soil for removal of heavy metals from the heavy-metal only contaminated soil column. After 7 pore volume flushing of the soil column, Cd removal efficiencies from the soil were 40% by SDS solution, 50% by SDS + NaI mixture, and 60% by surfactant foam. The flushing results implied that anionic surfactant and ligand can be efficiently applied to extraction of Cd from the heavy metal contaminated soil. Furthermore, surfactant foam flushing showed an increased flushing efficiency with enhancing the contact between surfactant solution and soil. However, Pb removal efficiency by these flushing methods did not show any difference unlike those of Cd. Second, this study eventually evaluated flushing methods for simultaneous removal of heavy metals and diesel-fuel from the soil column with 7 pore volume flushing. Diesel-fuel removal efficiencies were 50% by SDS + NaI flushing and 90% by SDS + NaI foam flushing. Cd removal efficiency by the foam flushing reached to 80% which was higher than the result of the previous heavy metals onlycontaminated soil experiment. This result implied that diesel-fuel could act as a metal-solvent while it contacted to heavy metals present in the soil. This study clearly showed that surfactant foam flushing simultaneously removed heavy metals and diesel fuel from the soil column.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2004.04a
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• pp.318-322
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• 2004

Arsenic is a toxic and carcinogenic metalloid, whose sources in nature include mineral dissolution and volcanic eruption. Abandoned mines and hazardous waste disposal sites are another major source of arsenic contamination of soil and aquatic systems. To predict concentrations of the toxic inorganic arsenic in aqueous phase. the biogeochemical redox processes and transport behavior need to be studied together and be coupled in a reactive transport model. A new reaction module describing the fate and transport of inorganic arsenic species (As(II)), dissolved oxygen, nitrate, ferrous iron, sulfate, and dissolved organic carbon are developed and incorporated into the RT3D code.

• Journal of The Korean Society of Grassland and Forage Science
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• v.26 no.1
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• pp.25-30
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• 2006

This experiment was conducted to compare the fresh yield and dry matter yield, and nutritive values of whole crop barley treated with Urea (200 kg/ha, T2) and ammonium sulfate fertilizer as 200 kg/ha (T3), 300 kg/ha (T4) and 400 kg/ha (T5) at the Bae-Ho reclaimed tideland. Korea from 2003 to 2005. Salt contents of soil in the ammonium sulfate plots (T3, T4, T5) were lower than those of T2. The fresh yields of ammonium sulfate plots (T3, T4, T5) were higher than those of T2 as 62% (p>0.05), 41% (p>0.05) and 23% (p<0.05), respectively. The dry matter yield of T3, T4 and T5 (ammonium sulfate) was significantly (p<0.05) higher at 5,080 kg/ha, 4,667 ka/ha, 4,040 kg/ha, respectively. The total digestible nutrients (TDN) yield tends to have a similar result. Crude protein (CP) content was highest in T3 and CP trends to decrease as the level of ammonium sulfate was increased. Total digestible nutrient (TDN) were high in T3 and T4. The sodium content of T3 and T4 were lower than T2. Based on the study, it was more desirable to use ammonium sulfate (200 kg N/ha) rather than Urea as fertilizer on reclaimed land in terms of forage production and nutritive value.

• Korean Journal of Environmental Agriculture
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• v.35 no.1
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• pp.6-14
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• 2016

BACKGROUND: Residual organochlorine pesticides (OCPs) are chemical substances that persist in the environment, bioaccumulate through the food web, and pose a risk of causing adverse effect to human health and the environment. They were designated as persistent organic pollutants (POPs) by Stockholm Convention. Greenhouse strawberry is economic crop in agriculture, and its cultivation area and yield has been increased. Therefore, we tried to investigate the POPs residue in greenhouse soil and strawberry.METHODS AND RESULTS: Extraction and clean-up method for the quantitative analysis of OCPs was developed and validated by gas chromatography (GC) with electron capture detector (ECD). The clean-up method was established using the modified quick, easy, cheap, effective, rugged, and safe(QuEChERS) method for OCPs in soil and strawberry. Limit of quantitation (LOQ) and recovery rates of OCPs in greenhouse soil and strawberry were 0.9-6.0 and 0.6-0.9 μg/kg, 74.4-115.6 and 75.6-88.4%, respectively. The precision was reliable sincerelative standard deviation (RSD) percentage (0.5-3.7 and 2.9-5.2%) was below 20, which was the normal percent value. The residue of OCPs in greenhouse soil was analyzed by the developed method, and dieldrin, β-endosulfan and endosulfan sulfate were detected at 1.6-23, 2.2-28.4 and 1.8-118.6 μg/kg, respectively. Those in strawberry were not detected in all samples.CONCLUSION: Dieldrin, β-endosulfan and endosulfan sulfate in a part of investigated greenhouse soil were detected. But those were not detected in investigated greenhouse strawberry. These results showed that the residue in greenhouse soil were lower level than bioaccumulation occurring.

• Economic and Environmental Geology
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• v.38 no.6 s.175
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• pp.657-662
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• 2005

Extractions fro fertilizer and soil samples were performed to yield the operationally defined fractions 'soluble' chromate (extractable with $NH_4NO_3$), 'exchangeable' chromate (extractable with phosphate buffer pH 7.2), and these results were compared with the data obtained by extractions with ammonium sulfate, borate buffer pH 7.2, saturated borax pH 9.6, and polyphosphate (Graham's salt). In order to maintain the pH of extractant solution about constant, the concentration of extractant buffer had to be raised to at least 0.5 M. The results strongly depended on the kind of extractant, and the solid: liquid ratio. For most of the samples investigated, the extraction efficiency increased in the order borate-sulfate-nitrate-phosphate. Whereas the recovery of $K_2CrO_4\;and\;CaCrO_4$ added to the samples of basic slags prior to the extraction was about complete, the recovery of added $PbCrO_4$ was highly variable. In soil extracts, the color reaction was interfered from co-extracted humics, which react with the chromate in weak acid solution during the time period necessary for color reaction (1 hour). However, this problem can be overcome by standard addition and subtraction of the color of the extractant solution. In soil extract of about pH < 7, organic material reduced chromate during the extraction period also, and standard addition of soluble chromate is recommended to prove recovery and the stability of chromate in the samples. In admixtures of soils and basic slags, results for hexavalent chromium were lower than from the mere basic slags. This effect was more pronounced in phosphate than in nitrate extracts. As a proficiency test, samples low in organic carbon from contaminated sites in Hungary were tested. The results from $NH_4NO_3$ extracts satisfactorily matched the results of the Hungarian labs obtained from $CalCl_2$ extractants.

• Journal of the Korean Society of Food Science and Nutrition
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• v.31 no.5
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• pp.754-759
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• 2002

In order to develope a new pretense applicable to industries, a bacterium which produces a remarkable amount of extracellular pretense were isolated from soil. About 10 bacterial strains producing pretense were isolated from samples of soil, and strain PANH765 showed the highest activity of pretense production among them. The strain was identified as Bacillus subtilis according to the Bergey's Manual of Systematic Bacteriology based on its morphological, cultural and physiological characteristics. B. subtilis PANH765 showed the maximal production of pro-tease in the medium containing 2.0% glucose, 1.0% yeast extract, 0.2% ammonium nitrate, 0.02% ferrous sulfate and 0.02% dipotassium hydrogen phosphate. Under the optimal condition with temperature of 3$0^{\circ}C$, initial pH of 7.0 and shaking speed of 150 rpm, the pretense production reached a maximum level with 36 hr cultivation (6.34 U).

• Journal of Soil and Groundwater Environment
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• v.18 no.7
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• pp.81-89
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• 2013

Concerns have been raised over the impact of nano materials on soil and groundwater environment with the increasing attention to the potential applications of carbon nano materials in various fields. Particularly, carbon nano materials introduced into water environment readily make complexes with humic acid (HA) due to their hydrophobic nature, so there have been increasing numbers of studies on the interaction between HA and carbon nano materials. In this study, we investigated the solubility of HA and multiwalled carbon nanotubes (MWCNT) in three different surfactant solutions of sodium dodecyl sulfate (SDS), Brij 30 and Triton X-100, and evaluated whether the HA can be effectively desorbed from the surface of MWCNT by surfactant. The objective of this study was to determine the optimal adsorption condition for HA to MWCNT. Futhermore, sodium dodecyl sulfate (SDS), Brij 30, Triton X-100 were used to elucidate the effect of desorption and separation on adsorbed HA on MWCNT. As a result, HA solution with 12.7 mg of total organic carbon (TOC) and 5 mg of MWCNT showed the highest adsorption capacity at pH 3 reacted for 72 hrs. Weight solubilizing ratio (WSR) of surfactants on HA and MWCNT was calculated. HA had approximately 2 times lower adsorption capacity for the applied three surfactants compared to those of MWCNT, implying that the desorption of HA may occur from the HA/MWCNT complex. According to the results of adsorption isotherm and weight solubilizing ratio (WSR), the most effective surfactants was the SDS 1% soluiton, showing 53.63% desorption of HA at pH 3.

• Journal of the Korean GEO-environmental Society
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• v.3 no.2
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• pp.23-33
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• 2002

Examined a practical use possibility of paper fly ash that is industrial by-product as a stabilization/hardening agent. Performed unconfined compression test, scanning electron microscopy and pH analysis etc. for 100% paper fly ash-soil mixtures and each paper fly ash-soil mixtures that add cement as the second addition and sulfate component of small quantity for strength promotion and so on. In all cases, strength of admixtures increased according as curing time and mixing ratio increases but almost strength is revealed at mixing early and expressed maximum strength increase efficiency at mixing ratio 9% with raw soil. Compare with the case that use paper fly ash only, in case of cement amount 10~30% was included in paper fly ash, strength of admixtures increases two times and 40% was included, that increases from five to eight times.