• Biotechnology and Bioprocess Engineering:BBE
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• v.9 no.6
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• pp.514-518
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• 2004

Many methods are used in the measurement of antioxidative capacity. These meth­ods require very complex procedures and pretreatment. Our suggestions for research will be simple and accurate methods for obtaining many kinds of samples, especially colored samples such as natural product extracts for measuring antioxidative capacities. For oxidation-reduction potential (ORP) system value, we examined the relationships between the ORP-pH system and the ORAC, FRAP methods. To evaluate ORP System value, we calculated the absolute slope/intercept from the linear regression of each standard material at different concentrations and ORP-pH system, and compared the correlations with ORAC and FRAP values.

• Korean Journal of Agricultural Science
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• v.39 no.4
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• pp.603-612
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• 2012

In this research, the feasibility of non-destructive measurement technique of pungency measurement was investigated for the red-pepper powders produced in different domestic areas in South Korea. The near-infrared absorption spectra in the range of 1100 nm~2300 nm was used to measure capsaicinoids content in red-pepper powders by using a NIR spectroscopy equipped with Acousto-optic tunable filters (AOTF). Fourth three different red-pepper powders from 14 different locations were collected and separated in three different particle size (below 0.425 mm, 0.425~0.71 mm, 0.71~1.4 mm) for the spectral measurements. The partial least square regression (PLSR) models to predict the capsaicinoids content depends on particle size were developed with the measured spectra. The determinant coefficients and standard errors of the developed models for the red-pepper powders of below 0.425 mm, 0.425~0.71 mm, and 0.71~1.4 mm were in the range of 0.859~0.887 and 12.90~12.99 mg/100 g, respectively. The PLS model with the pretreatment of Standard Normal Variate (SNV) for the red-pepper powders below 1.4 mm particle size showed the best performance with the determinant coefficient of 0.844 and the standard error of 14.63 mg/100 g.

• Horticultural Science & Technology
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• v.31 no.5
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• pp.573-579
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• 2013

This study was conducted to investigate optimal harvesting stage and the effects on cut roses of Korean cultivar harvested at different stages. Cut roses are harvested at three different flowering stages. The optimal harvesting stage of cut roses was different depending on varieties. The vase life of standard type 'Pink Song' and spray type 'Peace One' was extended when they were harvested in one and three stages, respectively. The vase life was generally increased when the cut roses were pretreated with a solution containing 2% sucrose + $200mg{\cdot}L^{-1}$ aluminum sulfate + $200mg{\cdot}L^{-1}$ $Mg(NO_3)_2$ + $50mg{\cdot}L^{-1}$ $CaCl_2$ as compared to the control regardless of the harvesting stage. And this pretreatment solution improved the flower quality of cut roses bred in Korea. But the effects of pretreatment were varied depending on the harvesting stage.

• Journal of the Korean Chemical Society
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• v.47 no.6
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• pp.578-584
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• 2003

Polychlorinated biphenyls (PCBs) known as environmental contaminants in soil were analyzed by the soil pollution standard process test and the static supercritical $CO_2$ extraction mode. It was shown that the percent average recoveries of PCBs by the soil pollution standard process test were ranged in 25-35% and the corresponding standard deviations were above 10%. In contrast, the percent average recoveries of PCBs by the static supercritical $CO_2$ extraction mode were 2-2.5 times higher and standard deviations were within 7%. These results indicate that static supercritical $CO_2$ extraction mode may be a useful alternative to sample pretreatment certified by the soil pollution standard process test. The increasing supercritical $CO_2$ pressure from 1130 psi to 1996 psi at $40^{\circ}C$ enhanced the recovery of all PCB congeners from soil. However, at same Tc and Pc, the equilibrium time (5 versus 60 minutes) had no effect on the recovery of each PCB congener. Finally, similar PCB recoveries were obtained under the same extraction condition, regardless of the molecular weight and structure (coplanar versus non-coplanar) of PCB congeners.

• Journal of Food Hygiene and Safety
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• v.36 no.6
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• pp.474-480
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• 2021

Sodium alginate is the sodium salt of alginic acid, commonly used as a food additive for stabilizing, thickening, and emulsifying properties. A relatively simple and universal analysis method is used to study sodium alginate due to the complex pretreatment process and extended analysis time required during the quantitative method. As for the equipment, HPLC-UVD and Unison US-Phenyl column were used for analysis. For the pretreatment condition, a shaking apparatus was used for extraction at 150 rpm for 180 minutes at room temperature. The calibration curve made from the standard sodium alginate solution in 5 concentration ranges showed that the linearity (R²) is 0.9999 on average. LOD and LOQ showed 3.96 mg/kg and 12.0 mg/kg, respectively. Furthermore, the average intraday and inter-day accuracy (%) and precision (RSD%) were 98.47-103.74% and 1.69-3.08% for seaweed jelly noodle samples and 99.95-105.76% and 0.59-3.63% for sherbet samples, respectively. The relative uncertainty value was appropriate for the CODEX standard with 1.5-7.9%. To evaluate the applicability of the method developed in this study, the sodium alginate concentrations of 103 products were quantified. The result showed that the detection rate is highest from starch vermicelli and instant fried noodles to sugar processed products.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2021.11a
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• pp.120-121
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• 2021

This study examines the performance of the pre-treatment process system to use CGS, a by-product generated in IGCC, as a concrete fine aggregate for construction materials, on the quality of CGS fine aggregate. As a result of the analysis, it is judged that the quality of fine aggregates of CGS can be improved at both density, absorption rate, and 0.08mm body passage amount after the hydroelectric screening process using water as a medium during the pretreatment process. It is believed that it can be used as basic data for national standard certification of CGS fine aggregates in the future.

• Fisheries and Aquatic Sciences
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• v.25 no.5
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• pp.264-275
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• 2022

A non-destructive environmental DNA protocol for the genetic analysis of sea cucumber (Apostichopus japonicus) resources DNA was established. Among the several commercial DNA extraction kits, the DNeasy^® Plant Mini Kit was selected as the best choice to obtain the high-quality genomic DNAs from the mucous sea cucumber. As the temperature and incubation time increased, the amount of extracted environmental DNA was also large, but it was judged that the increased amount did not affect as much as 2-3 times. Therefore, these conditions were not considered to be the main factors to consider in actual environmental DNA extraction. However, the amount of seawater relative to the size of the sample was judged as a major consideration, and a sufficient amount of environmental DNA for analysis was secured when stored within 1 min while stirring the volume of seawater corresponding to the total sea cucumber weight (g). In securing the environmental DNA of sea cucumbers, the mortality rate of sea cucumbers in all experiments was 0, and it was judged that the effects of sea cucumbers were not significant through this treatment. Through the results of this study, sea cucumber DNA research, which has been conducted in a destructive method, can be conducted non-destructively through environmental DNA analysis. Through this study, we have secured a standard protocol that can successfully extract the sea cucumber DNA through environmental DNA. It is not only excellent in terms of time and cost of traditional DNA analysis method currently used, but it is completely non-destructive in the ecosystem of the survey area. It is believed that the system can be transformed in a way that does not affect it. However, it is thought that various standard protocols should be established considering the characteristics of each type.

• Asian-Australasian Journal of Animal Sciences
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• v.13 no.11
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• pp.1604-1608
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• 2000

Penicillin antibiotics such as penicillin G, ampicillin and amoxicillin have been widely used in the pig industry to control salmonellosis, bacterial pneumonia, and urinary tract infections. Extensive use of antibiotics in veterinary clinics has resulted in tissue residues and bacterial resistance. To prevent unwanted drug residues entering the human food chain, extensive control measures have been established by both government authorities and industries. The demands for reliable, simple, sensitive, rapid and low-cost methods for residue analysis of foods are increasing. In this study, we established a rapid prediction test for the detection of pigs with unacceptable tissue residues of penicillins. The recommended therapeutic doses of three penicillins, penillin G (withdrawal time, 7 days), ampicillin (withdrawal time, 7 days) and amoxicillin (withdrawal time, 14 days), were administered to three groups of 20 pigs each. Blood was sampled before drug administration and during the withdrawal period. The concentration of penicillins in plasma, determined by a semi-quantitative ELISA, were compared to that of internal standard, 4 ppb, which corresponded to the Maximum Residue Limit in milk. The absorbance ratio of internal standard to sample (B/Bs) was employed as an index to determine whether drug residues in pig tissues were negative or positive. That is, a B/Bs ratio less than 1 was considered residue positive, and larger than 1 negative. All 60 plasma samples from pigs were negative to three penicillins at pretreatment. Penicillin G could be detected in the plasma of the treated pigs until day 4 post-treatment and ampicillin until day 2, whereas amoxicillin could be detected until day 10 of its withdrawal period. The present study showed that the semi-quantitative ELISA could be easily adapted to detect residues of penicillin antibiotics (penicillin G, ampicillin and amoxicillin) in live pigs.

• Korean Journal of Clinical Pharmacy
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• v.26 no.4
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• pp.312-317
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• 2016

Objective: Midazolam is mainly metabolized by cytochrome P450 (CYP) 3A. Inhibition or induction of CYP3A can affect the pharmacological activity of midazolam. The aims of this study were to develop a population pharmacokinetic (PK) model and evaluate the effect of CYP3A-mediated interactions among ketoconazole, rifampicin, and midazolam. Methods: Three-treatment, three-period, crossover study was conducted in 24 healthy male subjects. Each subject received 1 mg midazolam (control), 1 mg midazolam after pretreatment with 400 mg ketoconazole once daily for 4 days (CYP3A inhibition phase), and 2.5 mg midazolam after pretreatment with 600 mg rifampicin once daily for 10 days (CYP3A induction phase). The population PK analysis was performed using a nonlinear mixed effect model ($NONMEM^{(R)}$ 7.2) based on plasma midazolam concentrations. The PK model was developed, and the first-order conditional estimation with interaction was applied for the model run. A three-compartment model with first-order elimination described the PK. The influence of ketoconazole and rifampicin, CYP3A5 genotype, and demographic characteristics on PK parameters was examined. Goodness-of-fit (GOF) diagnostics and visual predictive checks, as well as bootstrap were used to evaluate the adequacy of the model fit and predictions. Results: Twenty-four subjects contributed to 900 midazolam concentrations. The final parameter estimates (% relative standard error, RSE) were as follows; clearance (CL), 31.8 L/h (6.0%); inter-compartmental clearance (Q) 2, 36.4 L/h (9.7%); Q3, 7.37 L/h (12.0%), volume of distribution (V) 1, 70.7 L (3.6%), V2, 32.9 L (8.8%); and V3, 44.4 L (6.7%). The midazolam CL decreased and increased to 32.5 and 199.9% in the inhibition and induction phases, respectively, compared to that in control phase. Conclusion: A PK model for midazolam co-treatment with ketoconazole and rifampicin was developed using data of healthy volunteers, and the subject's CYP3A status influenced the midazolam PK parameters. Therefore, a population PK model with enzyme-mediated drug interactions may be useful for quantitatively predicting PK alterations.

• Toxicological Research
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• v.29 no.4
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• pp.293-298
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• 2013

A method of detecting lead was developed using square wave anodic stripping voltammetry (SWASV) with DNA-carbon nanotube paste electrode (CNTPE). The results indicated a sensitive oxidation peak current of lead on the DNA-CNTPE. The curves were obtained within a concentration range of 50 $ngL^{-1}-20mgL^{-1}$ with preconcentration time of 100, 200, and 400 sec at the concentration of $mgL^{-1}$, ${\mu}gL^{-1}$, and $ngL^{-1}$, respectively. The observed relative standard deviation was 0.101% (n = 12) in the lead concentration of 30.0 ${\mu}gL^{-1}$ under optimum conditions. The low detection limit (S/N) was pegged at 8 $ngL^{-1}$ ($2.6{\times}10^{-8}M$). Results showed that the developed method can be used in real-time assay in vivo without requiring any pretreatment and pharmaceutical samples, and food samples, as well as other materials requiring water source contamination analyses.