• Journal of Applied Biological Chemistry
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• v.60 no.4
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• pp.343-349
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• 2017

This study was conducted to investigate the residual level and the amount of transfer to lettuce grown in field condition treated with the 5-methyl-1,2,4-triazolo[3,4-b][1,3]benzothiazole (Azoxystrobin). The field trials on lettuce were carried out at two different green houses located in Gwangju (Field 1) and Yongin (Field 2). Soil and lettuce samples were collected at different days after soil treatment of azoxystrobin with two different concentrations, respectively. Average recoveries for azoxystrobin ranged from 86.9 to 113.6% from soil and lettuce with the variation coefficient of 0.1-4.6%. The initial concentrations of azoxystrobin in Gwangju soil were 9.20, 11.00 mg/kg and decreased to 1.36, 2.70 mg/kg at 43 DAT (days after treatment) in field 1, while 1.06, 2.23 mg/kg decreased to 0.20 and 0.67 mg/kg at 36 DAT in field 2, respectively. The half-lives of azoxystrobin were about 19.4 and 23.3 days for the low and high concentration of azoxystrobin treated soils in field 1 and 11.5 and 17.8 days in field 2 soils, respectively. Residue levels of azoxystrobin in lettuce were not detected in filed 1 and field 2 soils, respectively.

• The Korean Journal of Pain
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• v.12 no.1
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• pp.36-42
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• 1999

Background: The current maximal recommended doses of lidocaine are 7 mg/kg with $5\;{\mu}g/ml$ of epinephrine. But in clinical practice, sometimes more doses of lidocaine are required to produce adequate regional anesthesia. Method: Twenty-two healthy women patients were divided into two groups and pretreated with valium 5 mg p.o., morphine 5 mg i.m., and midazolam 2 mg i.v. before operation. Of these, 7 mg/kg of 2% lidocaine with $5\;{\mu}g/ml$ of epinephrine were given to 11 patients epidurally. Initial 3 ml of epinephrine mixed lidocaine was given as a test dose and remaining doses were given 5 ml/30 sec with 3 min intervals. Radial arterial blood were drawn at 5, 10, 15, 20, 30, 45, 60, 90, 120 min to measure plasma lidocaine concentrations. After confirming all of the peak plasma concentrations of 7 mg/kg lidocaine were absolutely under $5\;{\mu}g/ml$, the other 11 patients were given 10 mg/kg of 2% lidocaine with $5\;{\mu}g/ml$ of epinephrine epidurally and blood samplings were taken according to the same method of 7 mg/kg group. The peak plasma concentration ($C_{max}$), time to reach to $C_{max}$ ($T_{max}$), time to reach to $T_4$, maximal sensory block level, systemic toxicity, and vital sign changes were investigated. Result: $C_{max}$ was significantly higher in 10 mg/kg group ($5.1{\pm}1.3\;{\mu}g/ml$) than 7 mg/kg group($3.3{\pm}0.5\;{\mu}g/ml$), but $T_{max}$ ($10.5{\pm}2.7$ min vs $10.9{\pm}3.1$ min) was not different. Time to reach $T_4$ was significantly shorter in 10 mg/kg group ($9.5{\pm}2.7$ min) than 7 mg/kg group ($12.7{\pm}3.2$ min) but maximal sensory block level ($T_{3.7{\pm}0.7}$ vs $T_{2.7{\pm}1.0}$) was not different. In four patients of 10 mg/kg group, peak plasma concentrations exceeded $5\;{\mu}g/ml$, but no systemic toxicities appeared. No significant vital sign changes were observed. Conclusion: The current maximal recommended doses of lidocaine, merely based on body weight are not always appropriate. Further studies are needed to determine more precise guideline of maximal doses that include various pharmacokinetic components.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.46 no.1
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• pp.40-46
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• 2001

Ozone ($O_3$)-induced changes in chlorophyll content and specific activities of antioxidant enzymes, such as superoxide dismutase (SOD), ascorbate peroxidase (APX), guaiacol peroxidase (GPX), dehydroascorbate reductase (DHAR) and glutathione reductase (GR) were investigated in two rice cultivars (Oryza sativa L.) grown under variable nutrient treatments. For this study, two rice cultivars of Ilpumbyeo (IL) and Keumobyeo#l (KM), which were known as resistant and susceptible to $O_3$, respectively, were exposed to $O_3$at 0.15ppm for 30 days and investigated with 10 days interval. The available nutrient regimes were varied by doubling the supply of nitrogen (N), phosphorus (P) and potassium (K) Within a basic fertilizer status (N, P, K; 15, 12, 12kg/l0a$^{-1}$ ). In both cultivars and at all nutrient status, chlorophyll content in $O_3$-treated plants decreased with prolonged treatment period, although higher N, P and K supply with $O_3$ treatment alleviated the decrease in chlorophyll content. The activities of almost all enzymes investigated for this study were decreased during initial stages of $O_3$- exposure except GPX which maintained higher activity throughout the exposure period than the non-treated plant. However, the antioxidant enzymes in $O_3$-treated plants showed almost the same or higher activities on 30 days after $O_3$ - exposure. The most significant changes in activities were observed in GR of the $O_3$-treated leaves. With the prolonged treatment period, the activity of GR at 30 days was increased by 3-8 times compared to those in 10 days. Most of the investigated enzymes showed very similar tendency to $O_3$ treatment in all fertilizer status. There was no observed evidence for enhanced detoxification of $O_3$-derived activated oxygen species in plants grown under higher fertilizer status compared with that in plants grown under basic fertilizer status. The increase in the activities of SOD, APX and GR in rice leaves by relatively long-term treatment with $O_3$ at low concentration is considered to indicate that the plant became adapted to the $O_3$ stress and the protection system increased its capacity to scavenge toxic oxygen species. Our results in two rice cultivars indicated that there was little difference in the activities of antioxidant enzymes between IL and KM, which were known as resistant and susceptible cultivar to $O_3$

• KOREAN JOURNAL OF CROP SCIENCE
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• v.56 no.2
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• pp.140-145
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• 2011

In order to establish the application method of slurry composting & biofilteration liquid fertilizer (SCB LF) in rice cultivation, experiments were studied on split application method of it and effects of it on soil chemical properties and rice yields. Land leveling by rotary tillage within 2 days after application of SCB LF, $NH_4$-N concentration in soil was maintained uniformly in all paddy field. Initial concentrations of $NH_4$-N and $NO_3$-N in soil were high at standard fertilization and 100% application of SCB LF as basal fertilization, however, after tillering stage they maintained similar concentrations in all experimental plots. $NO_3$-N content in infiltration water was slightly lower at 70% application of SCB LF as basal fertilization and 30% application of SCB LF as fertilization at panicle initiation stage than at standard fertilization. Yields of rice by split application of SCB LF were lower at 100% application of SCB LF as basal fertilization, however, those of the other application of SCB LF were similar with that of standard fertilization. In case of rice quality, perfect kernel rates were high and protein contents were lower at non-application and 100% application of SCB LF. Rice quality of 70% application of SCB LF as basal fertilization and 30% application of SCB LF as fertilization at panicle initiation stage were similar with that of standard fertilization.

• Korean Journal of Environmental Agriculture
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• v.31 no.2
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• pp.175-184
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• 2012

BACKGROUND: The aim of this study was to isolate and identify algicidal bacterium that tends to kill the toxic dinoflagellate Alexandrium catenella, and to determine the algicidal activity. METHODS AND RESULTS: Among of four algicidal bacteria isolated in this study, NH-12 isolate was the strongest algicidal activity against A. catenella. NH-12 isolate was identified on the basis of biochemical characteristics and analysis of 16S rRNA gene sequences. The isolate showed 97.67% homology with Pseudoalteromonas prydzensis ACAM $620^T$ (U85855), and was designated Pseudoalteromonas sp. NH-12. The optimal culture conditions of this isolate were $25^{\circ}C$, initial pH 8.0, and 3.0% (w/v) NaCl concentration. The algicidal activity of NH-12 was significantly increased to maximum value in the late of logarithmic phase of bacterial culture. As a result of 'cell culture insert' experiment, NH-12 is assumed to produce secondary metabolites, as an indirect attacker. When 10% culture filtrate of NH-12 was applied to A. catenella, over 99% of algal cells were destroyed within 24 h. In addition, the killing effects were increased in dose and time dependent manners. CONCLUSION(S): Taken together, our results suggest that Pseudoalteromonas sp. NH-12 could be a candidate for controlling of toxic algal blooms.

• Journal of the Korean Society of Food Culture
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• v.9 no.2
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• pp.125-130
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• 1994

This study was intended to observe the effect of the addition of soused shrimp(5%, 10%) and/or cooked glutinous rice flour(2.5%) on the changes of low molecular nitrogen compounds content of Kimchi during fermentation at $10^{\circ}C$ for 14 days. The pH, total acidity, free sugar, nitrite, dimethylamine(DMA) and volatile basic nitrogen(VBN) contents were measured. The nitrite contents were approximately 0.16 to 1.31 mg/Kg at the inital stage of fermentation. It was found that the nitrite contents of Kimchi samples with 10% soused shrimp$(S_2,\;GS_2)$ were relatively high among the Kimchi samples. However, nitrite was not detected after the stage of optimum maturity in all Kimchi samples. The dimethylamine(DMA) content of Kimchi samples were increased during the fermentation with increasing the soused shrimp concentration. Cooked glutinous rice flour enhanced the DMA production of Kimchi with soused shrimp. DMA content were 0.93-1.2 mg/kg at initial stage end 1.6-2.26 mg/kg at final stage of fermentation of the Kimchi with soused shrimp. As the fermentation period increased, the VBN contents of Kimchi samples with soused shrimp$(S_1,\;S_2,\;GS_1,\;GS_2)$ were apparently higher than those of Kimchi samples without it(C, G). Though the soused shrimp enhanced the volatile basic nitrogen production but cooked glutinous rice did not affected VBN production during Kimchi fermentation.

• Journal of Food Hygiene and Safety
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• v.30 no.2
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• pp.150-158
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• 2015

This article reports the development of an effective test procedure for detection of norovirus (NoV) in foods of diverse matrices. In this study, target foods included fermented milk, soybean paste, powders made from uncooked grains and vegetables, sesame leaves preserved in soy sauce, pickled mooli, and mooli. Viral recovery varied depending on the food matrices or elution buffers tested. Buffers were compared to determine effective elution buffers from artificially virus-contaminated foods. The conventional test procedure for concentrating viruses from food (elution-polyethylene glycol(PEG) precipitation-chloroform-PEG precipitation) was modified to save time by eliminating one PEG precipitation step. The modified procedure (elution-chloroform-PEG precipitation) was able to concentrate viruses more effectively than the conventional procedure. It also removed RT-PCR inhibitors effectively. The modified procedure was applied to target food for genogroup II NoV detection. NoV RNA was detected at the initial inoculum levels 3.125-12.5 RT-PCR units per 10-25 g tested food. The use of this newly established procedure should facilitate detection of low levels of norovirus in diverse foods.

• Applied Chemistry for Engineering
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• v.10 no.8
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• pp.1155-1160
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• 1999

The screening methodology modeling, dispersion modeling procedures for continuous and instantaneous releases of the gas phase flow from the storage tank and pressure relief valve were considered. This study was performed to develop the screening methodology for prediction and control of hazardous/toxic gas releases by estimating the 1-hr average maximum ground-level concentration of $Cl_2$ gas vs. downwind distance by incorporating source term model including the general/physical properties of released material and release mode of the $Cl_2$ storage tank of the chemical plant facilities, dispersion model, and meteorological/topographical data into the TSCREEN model. As the results of the study, it was found that dispersion modes of the dense gas were affected by the state of the released material, the released conditions, physical-chemical properties of released material, and the released modes (continuous and instantaneous releases), and especially largely affected by initial (depressurized) density of the released material and release emission rate as well as the wind velocity. Especially, this study was considered to release hazardous material as meteorological data. It was thought that this screening methodology can be useful as a preliminary guideline for application of the refined analysis model by developing the generic sliding scale methodology for various senarios selected.

• Applied Chemistry for Engineering
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• v.19 no.2
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• pp.173-178
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• 2008

Calcium lactate was prepared by reacting lactic acid with precipitated calcium carbonate (PCC) which was prepared by carbonation process (calcite) and solution process (aragonite). Effects of PCC morphology (calcite and aragonite) on calcium lactate by the solution process were investigated experimentally. Despite the slow forming rate at the initial stage, the final yield of calcium lactate appeared higher when calcite was used. Therefore, the maximum yield of calcium lactate using aragonite was 85.0% and that using calcite was 88.7%, respectively. For both cases, the optimum temperature for the preparation appeared at around $60^{\circ}C$. Furthermore, the increase in lactic acid concentration over 2.0 mol% increased slurry viscosity and deteriorated mass transfer, which resulted in low yield of calcium lactate for both cases. SEM analyses showed that the prepared calcium lactate appeared as plate-like crystal form, irrespective of PCC morphologies, reaction temperatures, and concentrations of lactic acid.

• Applied Chemistry for Engineering
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• v.25 no.6
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• pp.632-638
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• 2014

Batch adsorption studies including equilibrium, kinetics and thermodynamic parameters for the adsorption of new fuchsin dye using granular activated carbon were investigated with varying the operating variables such as initial concentration, contact time and temperature. Equilibrium adsorption data were fitted into Langmuir, Freundlich, Dubinin-Radushkevich and Temkin isotherms. Adsorption equilibrium was mostly well described by Langmuir Isotherm. From the estimated separation factor of Langmuir ($R_L$ = 0.023), and Freundlich (1/n = 0.198), this process could be employed as an effective treatment for the adsorption of new fuchsin dye. Also based on the adsorption energy (E = 0.002 kJ/mol) from Dubinin-Radushkevich isotherm and the adsorption heat constant (B = 1.920 J/mol) from Temkin isotherm, this adsorption is physical adsorption. From kinetic experiments, the adsorption reaction processes were confirmed following the pseudo second order model with good correlation. The intraparticle diffusion was a rate controlling step. Thermodynamic parameters including changes of free energy, enthalpy, and entropy were also calculated to predict the nature of adsorption. The change of enthalpy (92.49 kJ/mol) and activation energy (11.79 kJ/mol) indicated the endothermic nature of adsorption processes. The change of entropy (313.7 J/mol K) showed an increasing disorder in the adsorption process. The change of free energy found that the spontaneity of process increased with increasing the adsorption temperature.