• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.2
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• pp.149-154
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• 2007

An antibacterial substance to the Streptococcus mutans, a causative bacterium for decayed teeth, was isolated from the dried sea mustard, Undaria pinnatifida, and identified by GC and GC/MS. Acetone extract from the sea mustard (10.4 kg), was evaporated and partitioned to 4 fractions such as hexane, chloroform, butanol and water. The most active chloroform fraction were further purified through basic alumina, silicic acid and ODS column, successively, and finally, 3 antibacterial substances were isolated on the HPLC attached ODS column by using 95% MeOH and guided with UV detector (254 nm). Antibacterial substances (total 160mg, yield $1.5\times10^{-3}$%) had the same Rf value (0.42) on the TLC developed hexane diethyl ether acetic acid (80:30:1) and those methyl esters moved to 0.95. They were identified as the same unsaturated fatty acid, $C_{18:4,\;n-3}$ (3,6,9,12-octadecatetraenoic acid, stearidonic acid) compared relative retention times (15.5 min) with authentic fatty acid on the GC chromatogram. It was further confirmed unambiguously on the GC/MS giving molecular ion peak at m/z 290 which coincided with its methyl ester.

• Archives of Pharmacal Research
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• v.26 no.1
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• pp.70-75
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• 2003

The objective of the present study was to investigate the uptake process of 4-Phenylazobenzoxycarbonyl-Pro-Leu-Gly-Pro-D-Arg (Pz-peptide), a hydrophilic and collagenase-labile pentapeptide, by isolated hepatocytes. For comparison, the uptake of Pz-peptide by Caco-2 cells and colonic cells, two known paracellular routes of Pz-peptide, was also evaluated. A simple and sensitive reversed-phase HPLC assay method using UV detection has been developed. The coefficient of variation for all the criteria of validation were less than 15%. The method was, therefore, considered to be sutable for measuring the concentration of Pz-peptide in the biological cells. Pz-peptide was extensively uptaked into hepatocytes. The initial velocity of Pz-peptide uptake assessed from the initial slope of the curve was plotted as Eadie-Hofstee plots. The maximum velocity ($V_{max}$) and the Michaelis constant ($K_m$) were 0.190$\pm$0.020 $nmol/min/10^6$ cells and 12.1$\pm$3.23 $\mu$M, respectively. The permeability-surface area product ($PS{influx}$) was calculated to be 0.0157 ml/min/10^6$ cells. $V_{max}$ and $K_m$ values for Caco-2 cells were calculated to be 6.22$\pm$0.930 pmol/min/10^6$ cells and 82.8$\pm$8.37 $\mu$M, respectively, being comparable with those of colonocytes (6.04$\pm$1.03 pmol/min/10^6$ cells and 87.8$\pm$13.2 $\mu$M, respectively). $PS_{influx}$ values for Caco-2 cells and colonocytes were calculated to be 0.0751 $\mu$l/min/10^6$ cells and 0.0688 $\mu$l/min/10^6$ cells, respectively. The more pronounced uptake of Pz-peptide by hepatocytes, when compared with Caco-2 cells and colonocytes, is probably due to its specific transporter. In conclusion, Pz-peptide, a paracellularly transported pentapeptide in the intestine and ocular epithelia, was uptaked into hepatocytes extensively. Although Pz-peptide is able to be uptaked into the Caco-2 cells and colonocytes, it is less pronounced when compared with hepatocytes. $PS_{influx}$ values of Caco-2 cells and colonocytes for unbound Pz-peptide under linear conditions were less than 0.4% when compared with that of hepatocytes.

• Journal of agricultural medicine and community health
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• v.36 no.4
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• pp.218-226
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• 2011

Objectives: Paraquat (PQ) is a widely used ionic pesticide that is fatal when ingested accidentally or for suicidal purposes. It is thought that chronic exposure of PQ is related with the development of Parkinson's disease, but epidemiological studies have not yet confirmed that theory. This study attempted to estimate the possibility of environmental PQ exposure through soil and water. Materials and Methods: We analyzed the amount of decomposed PQ solution in wet soil after exposure to ultraviolet light. An artificial rainfall condition was simulated over soil sprayed with PQ to measure the amount of eluted PQ. In addition, PQ was diluted in water from three differently rated rivers and the changes in PQ concentration were measured after ultraviolet exposure over one month. High performance liquid chromatography/ultra violet detection was used to analyze the concentrations of PQ. Results: In the method we used, the recovery rate of PQ showed a precision rate less than 5%, an accuracy greater than 88%, and the calibration equation was y=5538.8x-440.01($R^2$=0.9985). There were no significant differences in the concentrations of PQ obtained from the three specimens over a 1-week period. From the PQ-sprayed soil, the artificial rainfall conditions showed no PQ elution over a 1-month period, and there was no significant differences in PQ concentrations according to ultraviolet exposure among the three samples. Conclusions: PQ remains well adsorbed naturally in soil. However, it may still exist in an integrated state for a long time in the hydrosphere, so the possibility of PQ exposure through drinking water cannot be disqualified.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.19 no.1
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• pp.20-30
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• 1993

Liquid Chromatographic behavior of Pd(II) in Isonitosoethylacetoacetate imine IEAA-NR: R=H, CH3, C2H5, n-C3H7, n-C4H9, C6H5-CH2) Chelates were investigated by reversed phase high performance 1iquid chromatography on Micropak MCH-5 Column using Methanol /water as mobile phase. The optimum condition for the separation of Pd-Isonitrosoethylacetoacetate imine chelates were examined with respect to the flow rate, mobile phase strength. It was found that Pd(IEAA-NR)2 chelates were eluted in an acceptable range of the capacity factor value (0 $\leq$ log k' $\leq$ 1), The dependence of the logarithm of capacity factor(k') on the volume fraction of water in mixture with in the binary mobile phase was examined. Also, the dependence of k'on the liquid-liquid extraction distribution constant in methanol-water / n-alkane extraction system was on system was invert tigated for Pd(IEAA-NR)2. Both kinds of dependence are linear, which suggests that the retention of the electroneutral metal chelates be largely due to the solvophobic effect.

• Korean Journal of Clinical Pharmacy
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• v.12 no.2
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• pp.71-75
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• 2002

This study was carried out to compare the bioavailability of $Ceclex^{(R)}$ (test drug, cefaclor 250 mg/capsule) with that of $Ceclor^{(R)}$ (reference drug) and to estimate the pharmacokinetic parameters of cefaclor in healthy Korean adult. The bioavailability was examined on 20 healthy volunteers who received a single dose (250 mg) of each drug in the fasting state in a randomized balanced 2-way crossover design. After dosing, blood samples were collected for a period of 6hours. Plasma concentrations of cefaclor were determined using HPLC with UV detection. The pharmacokinetic parameters $(AUC_{0-6hr},\;C_{max},\;T_{max},\;AUC_{int},\;K_e,\;t_{1/2},\;Vd)$ F, and CL/F) were calculated with non-compartmental pharmacokinetic analysis. The ANOVA test was utilized for the statistical analysis of the $T_{max},\;log-transformed\;AUC_{0-6hr}\;log-transformed\;C_{max},\;t_{l/2},\;V_d/F$, and CL/F. The ratios of geometric means of AUC0-6hr and $C_{max}$ between test drug and reference drug were $103.2\%\;(6.74\;{\mu}g{\cdot}hr/ml\;vs\;6.53{\pm}g{\cdot}hr/ml)\;and\;100.4\%\;(4.85\;{\mu}g\ml\;vs\;4.82\;{\mu}g/ml)$, respectively. The $T_{max}$ of test drug and reference drug were $0.9\pm0.38\;hr\;and\;0.83\pm0.34$ hrs, respectively. The $90\%$ confidence intervals of mean difference of logarithmic transformed $AUC_{0-6h},\;and\;C_{max}$ were log $0.98{\sim}log$ 1.08 and log $0.88{\sim}log1.15$, respectively. It shows that the bioavailability of test drug is equivalent with that of reference drug. The estimated half-life of this study was longer $(1.21\pm0.27\;hrs\;vs\;0.5-1\;hr)$, the Vd/F was larger $(68.89\pm25.72L$ vs 24.9L), and the CL/F was higher $(38.62\pm7.09\;L/hr$ vs 24.9 L/hr) than the previously reported values.

• Analytical Science and Technology
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• v.17 no.6
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• pp.520-526
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• 2004

To determine 6 anti-impotence drug-like compounds such as sildenafil, vardenafil, tadalafil, homosildenafil, hydroxyhomosildenafil and hongdenafil in food, simultaneously, high performance liquid chromatography was applied. In the case of solid sample, it was extracted in organic solvents after homogenizing with mortar and pestle. Whereas liquid sample was just diluted in water and then extracted in organic solvents. Maximum lengths of UV for targets have been identified on photodiode array spectra. As results, vardenafil, hongdenafil, hydroxyhomosildenafil, sildenafil, homosildenafil, and tadalafil were eluted in order using $C_{18}$ column in acetonitrile containing phosphoric acid as the mobile phase. The maximum wavelength (${\lambda}_{max}$) was 216 nm for vardenafil, 233 and 282 nm for hongdenafil, 222 and 293 nm for hydroxyhomosildenafil, sildenafil and homosildenafil, and 284 nm for tadalafil. The overall recoveries were ranged from 95% to 109% and the limit of detection was about 0.04 mg/kg at signal/noise>3. Levels of targets in the selected food samples were 1.7 (hongdenafil) ~ 63 (tadalafil) mg/one dose.

• Korean Journal of Food Science and Technology
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• v.52 no.2
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• pp.113-118
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• 2020

We investigated the quality characteristics and antioxidant capacities of Korean commercial yogurt. Twenty commercial yogurt samples exhibited a pH of 4.05-4.51, titratable acidity of 0.80-1.45%, viable counts of 6.65-9.39 log CFU/g, and total phenolic content of 0.71-2.92 mg gallic acid equivalent/g dry weight (dw). Lactic acid was the major organic acid detected by HPLC with UV detection, and its content was 5.4 times and 46.5 times higher than that of malic acid and citric acid, respectively. The tested commercial yogurt samples exhibited antioxidant potential (1.62-8.95 mM trolox equivalent/g, dw) measured based on scavenging activities of DPPH and ABTS radicals. The average antioxidant potentials of commercial set yogurt containing fruit syrup were significantly (p<0.05) higher than that of cream and plain yogurt. A positive linear correlation was observed between the total phenolic content and the antioxidant capacities, suggesting that phenolic components are likely to contribute significantly to the antioxidant potential of commercial yogurt.

• Journal of Sericultural and Entomological Science
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• v.45 no.2
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• pp.90-95
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• 2003

This study was carried out to identify of C3G (cyanidin-3-glucoside) from mulberry fruits and quantify with different varieties. C3G of mulberry fruits was extracted with 1％ HCl-MeOH and purified with open column (5${\times}$90cm) which filled with Amberlite IRC-50 ion exchange resin. The $\lambda$max ranges of the purified C3G on UV/vis spectrum were 516nm and 280nm. Also, molecular weight of C3G from mulberry fruits by LC-Mass was determined as 449. From above results, we concluded that anthocyanin pigment of mulberry fruits was C3G only. The cyanidin-3-glucoside (C3G) was separated and quantified by High Performance Liquid Chromatography (HPLC) system using a Nova-Pack C$\_$18/ column. Mean content of the 35 tested accessions was 0.89％. Also fruity characteristics as well as C3G content to select the desirable mulberry varieties for the production of fruit were researched and analyzed. We selected three suitable varieties such as 'Susungppong', 'Kangsun', and 'Jeolgokchosaeng(Chungpuk)'.

• Korean Journal of Food Science and Technology
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• v.53 no.3
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• pp.296-303
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• 2021

The antioxidant and anti-neuroinflammatory activities of water, 30, 70, and 100% ethanol extracts of leaves of three different species of bamboo (Phyllostachys nigra, P. bambusoides, and Sasa borealis) were investigated. The levels of total polyphenol and flavonoid were measured, and antioxidant activity was evaluated using various antioxidant assays (DPPH, ABTS, and FRAP). Lipopolysaccharide (LPS)-induced BV2 microglial cell activation was used to evaluate the anti-neuroinflammatory properties of the bamboo leaf extracts. Treatment with both aqueous and ethanolic extracts showed no cytotoxicity in BV-2 microglial cells. Pre-treatment of BV-2 cells with bamboo leaf extracts significantly inhibited LPS-induced excessive production of nitric oxide in a dose-dependent manner. Moreover, phytochemical analysis based on the extraction solvent showed that caffeic acid, p-coumaric acid, and tricin are the principal constituents of all three bamboo leaf extracts. Therefore, our findings suggest that bamboo leaf extract contains potent antioxidants and anti-neuroinflammatory compounds that can be used as potential therapeutic agents for the treat neuroinflammatory diseases.

• Tribology and Lubricants
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• v.37 no.6
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• pp.232-239
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• 2021

Petroleum is the most consumed energy source in Korea with a usage rate of 38.7% among the available primary energy sources. The price of liquid petroleum products in Korea includes taxes such as transportation·environment·energy tax. Thus, illegal production and distribution of liquid petroleum is widespread because of its huge price difference from that of the normal product and its tax-free nature. Generally, the illegal petroleum product is produced by mixing liquid petroleum with other similar petroleum alternatives. The two kinds of gasoline, common gasoline and premium gasoline, are being distributed in Korea. The premium gasoline is often adulterated with cheaper common gasoline that lowers the octane number of gasoline. It is possible to distinguish them with their color difference, green and yellow for different grade gasoline. However, when small volume of common gasoline is added to premium gasoline, it is difficult to determine whether premium gasoline contained common grade or not. In this study, we inspect gasoline, which is illegally produced by mixing common gasoline to premium gasoline. When the ratio of mixing common gasoline is increased, premium gasoline shows decreasing absorbance at 600 nm and 650 nm under UV-Vis spectrometer. Moreover, the detected intensity (mV·s) of green dye in high performance liquid chromatography (HPLC) was decreased by common gasoline under 0.99 correlation value. The more the common gasoline is mixed, the more olefin and naphthene are detected by gas chromatography. In addition, trimethyl pentane as octane improver, paraffin and toluene are decreased by common gasoline mixing. The findings of this study suggests that illegal petroleum can be identified by analysis of components and simulated samples.