• Korean Journal of Soil Science and Fertilizer
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• v.45 no.2
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• pp.227-234
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• 2012

Recently, the population of toxic and/or unusable jellyfish is increasing during summer along the east coast of Korea, causing massive economical and ecological damage to fisheries, nuclear power plant and marine environment. To solve this problem, this study was carried out using jellyfish as a potential soil additive for horticulture. The jellyfish was solidified and homogenized, then mixed with a commercial bed soil. Allium tuberosum ROTH was planted to control bed soil (BS) and jellyfish powder mixed bed soil groups (Mixed bed soil, MBS), and following parameters were measured during five weeks: water content, electrical conductivity and growth of leaves. At the end of the experiment, bacterial community structures of each pot were analyzed by DGGE. The relative water adsorption of jellyfish powder was about 2.5 times greater compared to its dry weight. The water content of MBS group was significantly higher than BS group 6.5 to 14.2%, and the electric conductivity of MBS group was measured around 2.8 dS/m where BS group was resulted average of 1.8 dS/m. However, the leaves of BS group were grown 30% longer compared to MBS group. DGGE analysis of MBS group was shown in high number of phylum Bacteroidetes and increased diversity of Sphingobacteriia compared to BS group. Jellyfish powder as a soil additive surely will be a good candidate as humectant and microbiota stimulator, although there are several obstacles such as high electrical conductivity and residual alum salt which used for solidification of jellyfish.

• Applied Chemistry for Engineering
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• v.32 no.4
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• pp.461-466
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• 2021

In this article, a portable and cost-effective voltammetric biosensor with nanoparticles was developed for the measurements of heterogeneous nuclear ribonucleoprotein A1 protein (hnRNP A1) biomarker which can potentially be used for lung cancer diagnosis. Gold nanoparticles were first electrodeposited onto screen printed carbon electrode (SPCE) followed by immobilizing a single stranded DNA aptamer specific to hnRNP A1 onto the electrode surface. Ethanolamine was also used when immobilizing DNA aptamer on the surface to prevent signals from non-specific adsorption events. Sequential injection of hnRNP A1 biomarker and anti-hnRNP A1 conjugated with alkaline phosphatase (ALP) onto the aptamer chip surface allows to form the sandwich complex of DNA aptamer/hnRNP A1/ALP-anti-hnRNP A1 on the electrode surface which further reacted with 4-aminophenyl phosphate (APP). The electrocatalytic reaction of the enzyme, ALP, and the substrate, APP, resulting in the oxidative current response changes at -0.05 and -0.17 V (vs. Ag/AgCl) against the hnRNP A1 concentration was measured using cyclic and differential pulse voltammetry, respectively. The Au nanoparticles-integrated voltammetric biosensor was applied to analyze human normal serum solutions possibly suggesting potential applicability for lung cancer diagnosis.

• Korean Journal of Soil Science and Fertilizer
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• v.24 no.4
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• pp.248-253
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• 1991

This study examines the effect of submergence on transformations of inorganic phosphorus and the relation between fractions of inorganic phosphorus and adsorbed phosphorus in Gangseo (paddy soil), Yesan (non-cultivated soil), and Jungdong soil (upland soil). The soils were submerged with glucose sol'n at $28^{\circ}C$ for 17 days. After, the soils were incubated with phosphate solution at $25^{\circ}C$ for 24 hours. The seguential fractionation of inorganic phosphorus and of iron were conducted to investigate transformations of them. Results obtained are as follows; 1. By submergence, Bray I-P were decreased from 53mgP/kg to 48mgP/kg in Gangseo, from 3mgP/kg to 1mgP/kg in Yesan, and from 120mgP/kg to 56mgP/kg in Jungdong soil. 2. $NH_4F$ extractable P was dominant fraction of adsorbed P. It was transformed into NaOH extractable P by submergence in Jungdong soil. 3. Dithionite-citrate-bicarbonate extractable iron (crystalline Fe) was transformed to oxalate extractable iron (amorphous Fe) by submergence in Yesan soil.

• Microbiology and Biotechnology Letters
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• v.32 no.3
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• pp.224-229
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• 2004

Several microorganisms (esterase-producing group) were isolated by the solid selective media containing-naphtylacetate. Among them, strain 366M-9 having a high activity of cephalosporin-C deacetylase (CAH; EC 3.1.1.41) was selected. The strain 366M-9 was identified as Bacillus sphaericus on the basis of morphological, physiological, and biochemical characteristics. The production of CAH reached at maximum value after 32 hrs, when cultivated in the optimal medium containing dextrin 2.5%, peptone 2.5%, sodium chloride 0.5%, dipotassium phosphate 0.25%, ferrous sulfate 0.02%, and 7-ACA 0.1% at $30^{\circ}C$ with initial pH 6.0. The CAH was purified by 3 steps with ammonium sulfate precipitation, adsorption chromatography on hydroxyapatite column, and Sephadex G-200 gel chromatography. The final enzyme preparation was homogeneous as judged by the analysis of SDS-PAGE and HPLC. Optimum temperature and pH for CAH activity were $50{\circ}C$ and around 7.0, respectively. And the enzyme was stable at pH 6.0～8.0, up to $50^{\circ}C$. The Michaelis-Menten constants ($K_{m}$ ), $V_{max}$ were 0.87 mM and 1.22 unit/ml, respectively.

• Journal of Food Hygiene and Safety
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• v.13 no.3
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• pp.206-212
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• 1998

An improved antibody-coated sensor system based on quartz crystal microbalance was developed for the detection of Salmonella spp. An antibody against Salmonella common structural antigen was immobilized onto one gold electrode of the piezoelectric quartz crystal surface by various immobilization procedures. The best results in sensitivity and stability were obtained with the thin layers of protein A and 3,3'-dithiopropionimidate.2HCI(DTBP), a homobifunctional thiol-cleavable crosslinker. After the addition of a S. typhimurium suspension into a reaction cell with 0.1 M sodium phosphate buffer, pH 7.2, the resonant frequency owing to S. typhimurium adsorption decreased conspicuously. The antibody-immobilized crystals prepared by the gold-protein A complex formation and DTBP thiolation showed the frequency shifts of 80 and 283 Hz, respectively. The time required for maximum frequency shift was about 30~60 min. The antibody-coated crystal could be reused for 6~8 consecutive assays.

• Environmental Engineering Research
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• v.19 no.1
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• pp.37-40
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• 2014

This research investigates the quality changes during composting of bagasse and pig manure amended with 30% of surfactant-coated charcoal (SC). Two treatments, 30% uncoated charcoal (UC) amendment and no charcoal (NC) amendment, were done as control. Charcoal was coated with 0.37 mM tetradecyltrimethylammonium bromide (TDMA), a cationic surfactant, at the dosage of 10 g/L. At the end of the composting period, the carbon to nitrogen (C/N) ratio of SC amendment was 9.7; whereas, the C/N ratios of UC and NC amendment were 12.6 and 21.4, respectively. Plant nutrients contents of the compost produced from SC amendment were 20.7 mg $NH_4{^+}-N/g$, 42.8 mg $NO_3{^-}-N/g$, and 41.7 mg P/g. High nitrate and phosphate concentrations in SC amendment were due to the adsorption of these anions on the positive charge of TDMA. Desorption of plant nutrients retained in the compost pellets was also investigated. It was predicted that nitrate was fully desorbed from a pellet at 23 days for SC amendment, which was later than UC (14 days) and NC (10 days) amendment. A slow release of nitrate from the compost pellet will reduce the nitrate leaching into the environment. Thus, the adding of SC in the compost pile is one of the alternative methods to improve the quality of compost and plant nutrient retention.

• Journal of Pharmaceutical Investigation
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• v.31 no.4
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• pp.225-232
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• 2001

The present study was carried out to observe the effect of liposome dispersed gel formulation (Lipogel) on topical delivery of ascorbyl palmitate (AsP). Neutral and negatively charged MLV liposomes containing AsP were prepared with dimyristoylphosphadtidylcholine (DMPC) and dicetyl phosphate (DCP), and dispersed to poloxamer gel matrix. In the hydrolysis study in rat's skin homogenates, AsP hydrolyzed to ascorbic acid (AsA) according to the first-order kinetics with the rate constant of $2.46{\times}10^{-2}\;min^{-1}$. In the passive skin penetration study using Franz diffusion cell, lipogel systems exhibited the greater values in the flux $(J_s)$ and the amount penetrated $(Q_p)$ compared to control hydrogels containing diethyleneglycol monoethyl ether $(Transcutol^{\circledR})$ as a solubilizing agent and a penetration enhancer for AsP. The total amount penetrated $(Q_{Total})$, which is expressed as a summation of $Q_P\;and\;Q_L$, for lipogel system was about 1.4 times higher in average than that of control hydrogel. However the amount localized in the skin $(Q_L)$ was similar in both formulations. As a result, lipogel system enhanced the skin penetration of AsP, possibly due to the increase in local concentration of AsP by preferential adsorption of liposome to the skin and the enhancing effect of phospholipid in liposome composition. Moreover it was expected that the penetrated AsP would generate AsA during skin penetration by the skin esterase. In conclusion, lipogel formulation was considered as a good candidate for topical delivery of AsP.

• Korean Journal of Food Science and Technology
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• v.31 no.1
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• pp.1-6
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• 1999

A piezoelectric (PZ) biosensor system detecting Salmonella spp. was developed. The system consisted of an oscillator, a frequency counter and an antibody-immobilized quartz crystal. An anti-Salmonella antibody was immobilized on one gold. surface of the quartz crystal with protein A. Salmonella detection was made by measuring resonant frequency shift owing to a mass change by specific binding of microbial cells to the gold surface of the PZ crystal. The PZ antibody sensor was operated optimally at 0.1M phosphate buffer, pH 7.2 and $35^{\circ}C$. The sensor was quite specific to Salmonella spp. The obtained frequency shift was correlated with the Salmonella concentration in the range of $10^5{\sim}10^6\;CFU/mL$. The frequency shift increased further by addition of polystyrene beads. The Salmonella detection which is indicated by a steady-state microbial adsorption to the quartz crystal was accomplished within 50min.

• Journal of the Korean Chemical Society
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• v.35 no.4
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• pp.374-378
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• 1991

The electrochemical reduction behavior of Bilirubin (BR) in phosphate buffer (pH 7.8) solution was studied by DC polarography, differential pulse polarography, cyclic voltammetry and controlled potential coulometry. In DC polarogram, two reduction waves of BR were found. The half wave potentials of two reduction waves were -1.32 and -1.51 volts vs. Ag/AaCl respectively. The current type of 1st reduction wave was diffusion-controlled and the 2$^{nd}$ reduction wave was diffusion current containing a little kinetic current. The electrochemical reduction process of BR at each reduction step was all irreversible. The prewave appeared at lower concentration than 3.4 ${\times}$ 10$^{-4}$M, this prewave was identified as adsorption prewave. And the number of electron transfered in reduction steps, n$_{app}$ was two for the 1st reduction step and one for the 2$^{nd}$ reduction step.

• Bulletin of the Korean Chemical Society
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• v.28 no.5
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• pp.783-790
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• 2007

The immobilization of proteins and their molecular interactions on various polymer-modified glass substrates [i.e. 3-aminopropyltriethoxysilane (APTS), 3-glycidoxypropyltrimethoxysilane (GPTS), poly (ethylene glycol) diacrylate (PEG-DA), chitosan (CHI), glutaraldehyde (GA), 3-(trichlorosilyl)propyl methacrylate (TPM), 3'-mercaptopropyltrimethoxysilane (MPTMS), glycidyl methacrylate (GMA) and poly-l-lysine (PL).] for potential applications in a nanoarray protein chip at the single-molecule level was evaluated using prismtype dual-color total internal reflection fluorescence microscopy (dual-color TIRFM). A dual-color TIRF microscope, which contained two individual laser beams and a single high-sensitivity camera, was used for the rapid and simultaneous dual-color detection of the interactions and colocalization of different proteins labeled with different fluorescent dyes such as Alexa Fluor® 488, Qdot® 525 and Alexa Fluor® 633. Most of the polymer-modified glass substrates showed good stability and a relative high signal-to-noise (S/N) ratio over a 40-day period after making the substrates. The GPTS/CHI/GA-modified glass substrate showed a 13.5-56.3% higher relative S/N ratio than the other substrates. 1% Top-Block in 10 mM phosphate buffered saline (pH 7.4) showed a 99.2% increase in the blocking effect of non-specific adsorption. These results show that dual-color TIRFM is a powerful methodology for detecting proteins at the single-molecule level with potential applications in nanoarray chips or nano-biosensors.