• Analytical Science and Technology
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• v.12 no.5
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• pp.375-381
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• 1999

Near infrared spectrophotometry(NIR) was developed as a non-invasive determination of blood alcohol. The first pure alcohol/water samples were prepared with ethanol concentration from 0.01 to 0.1%(w/w). Analysis of the second-derivative data was accomplished with multilinear regression(MLR). The standard error of calibration(SEC) of ethanol in ethanol/water solutions was approximately 0.0039%. The calibration models were established from the blood alcohol spectra by MLR and PLSR analysis. The best calibration was built with the second-derivative spectra of 2266 and 2326 nm by MLR. Second-derivative spectra in the spectral ranges of 1100~1340, 1500~1796 and 2064~2300 nm with four PLSR factors provided the standard error of prediction(SEP) of 0.030%(w/w). These results indicate that NIR may be applied for a fast non-invasive determination of alcohol in the blood.

• Journal of the East Asian Society of Dietary Life
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• v.26 no.2
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• pp.192-199
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• 2016

The antioxidative activity and antimutagenic activity of the ethanol extracts from pericarp and seeds of wild grape (Vitis coignetiea) were analyzed in this study. The antioxidative activity of the extracts from wild grape was determined using 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) assay. The antimutagenic activity of the extracts was evaluated on Salmonella typhimurium TA98 and TA100 by Ames test using 4-nitroquinoline 1-oxide (4-NQO) and sodium azide as mutagens. In the antioxidative activity determination, $IC_{50}$ values of the DPPH radical scavenging activity of the extracts from pericarp and seeds were 27.16 ppm and 7.61 ppm, respectively. Additionally, ABTS radical scavenging activities of pericarp and seed extract were 99.75% and 98.87% at 200 ppm, respectively. In the antimutagenic activity determination, pericarp extract at 5 mg/plate inhibited 72.6% and 74.3% of mutagenicity of S. typhimurium TA98 induced by 4-NQO and sodium azaid, respectively. Also, the mutagenicity inhibition rates of seed extract at 5 mg/plate were 77.8% and 74.5% in S. typhimurium TA100 induced by 4-NQO and sodium azaid, respectively. These results demonstrate that the ethanol extract from wild grape has remarkable antioxidant activity and antimutagenicity.

• Journal of the Korean Society of Food Science and Nutrition
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• v.17 no.2
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• pp.136-143
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• 1988

This study was performed to provide the optimal conditions of quantitative analysis for free amino acid in fermented protein foods. The water extractable free amino acid from dairy fermented foods was extracted effectively at $75^{\circ}C$ for 40 min., while it were extracted from fermented soy products at $40^{\circ}C$ for 3 hours. A close results of free amino acid content to those from amino acid analyzer were obtained using OPDA method with lysine standard after deproteinizing with 1% picric acid. 95% ethanol used as a deproteinizing reagent could give a comparable results to those from picric acid treatment in determining free amino acid content using OPDA method. Therefore, ethanol treatment was more recommendable than picric acid treatment which has some troubles in removing excess picric acid through Dowex resin column. The most desirable precipitation method for free amino acid determination using TNBS method was 95% ethanol treatment among the various deproteinizing procedure. The copper salt method was not suitable owing to its lacking reproducibility and pronounced discrepancy in determining free amino acid.

• Journal of the Korean Society of Food Science and Nutrition
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• v.29 no.4
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• pp.732-736
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• 2000

The purpose of this study was to investigate the extraction method of phenolic compounds and antioxidant activities of the aerial part of Epimedium koreanum NAKAI (EKN). The antioxidant activities of EKN were tested with by hydrogen donating ability, inhibition of lipid peroxidation, and inhibition of LDL oxidation. The most suitable conditions for the extraction of phenolic compounds from EKN were to use 60% ethanol by 3 times, and the yield of extract (dry basis) was 22%. In the extraction efficiency of phenolic compounds, 60% ethanol as extracting solvent was superior to water. Sixty% ethanol extract of EKN was found to have an ability of hydrogen donating to DPPH. MDA determination showed the 95% inhibitory effect against linoleic acid oxidation by the addition of 700 ppm EKN extract. Also, about 70% of LDL oxidation was inhibited by the addition of 500 ppm.

• Korean journal of food and cookery science
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• v.30 no.6
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• pp.785-791
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• 2014

The antioxidative activities of beverages with water or ethanol extracts from Maegmundong (Liriope platyphylla) were investigated with free amino acid and mineral analysis, as well as saponin, total phenolics and flavonoid determination. Antioxidative activity was evaluated by electron donating ability and ABTS radical scavenging activity. There was only a small difference between water extract beverages and ethanol-extract beverages with respect to their electron donating ability and ABTS radical scavenging activity, although the total saponin, total phenolics and flavonoid were found to be greater in the ethanol extract beverages than in the water extract beverages. Three major free amino acids of the Magemundong beverages with water- or ethanol extract were asparagine (58.30, 60.68 mg%), methionine (15.10, 13.95 mg%, respectively) and proline (12.31, 14.00 mg%, respectively). The most abundant mineral in the Maegmundong beverage with water and ethanol extract was potassium (238.68, 244.32 mg%, respectively).

• Journal of the Korean Wood Science and Technology
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• v.50 no.5
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• pp.338-352
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• 2022

Herein, water and ethanol extracts were obtained from the leaves, branches, kernels, and pericarp of Quercus gilva and subsequently analyzed for antioxidant activity and circadian rhythm regulation effects. Candidate components that may affect circadian rhythm and antioxidant activity were investigated to discover potential functional materials. Antioxidant activity was analyzed via 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical scavenging activity assays, showing that the hot water extract exhibited higher activity than that of the ethanol extract. In particular, the branch extract showed high antioxidant activity. By measuring total contents of polyphenols, flavonoids, and tannins, the hot water branch extract showed the highest concentrations, highlighting their significant contribution to the antioxidant activity. Examination of the circadian rhythm regulation of each extract showed that the ethanol extract exhibited greater impacts on the circadian rhythm amplitude compared to the water extract. The branch ethanol extract induced circadian rhythm amplitude changes via clock gene Bmal1 expression regulation. Determination of 12 phenolic compound concentrations showed that the branch ethanol extract contained many phenolic compounds, including catechin. This suggests that these com- pounds affected circadian rhythm regulation. In conclusion, the hot water branch extract has potential as an natural antioxidant material, while the corresponding ethanol extract has potential as a functional material for regulating circadian rhythm.

• Korean Journal of Medicinal Crop Science
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• v.21 no.6
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• pp.486-492
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• 2013

This study has been conducted to establish the optimal extraction process and HPLC analysis method for the determination of marker compounds as a part of the materials standardization for the development of health functional food materials from Astragali radix. Five extraction conditions including the shaking extraction at room temperature and the reflux extraction at $85^{\circ}C$ with 30%, 50% and 95% ethanol were evaluated. Reflux extraction with 50% ethanol showed the highest extraction yield as $27.27{\pm}2.27%$, while the extraction under reflux with 95% ethanol showed significantly the lowest yield of $10.55{\pm}0.24%$. The quantitative determination methods of calycosin-7-O-${\beta}$-D-glucoside and calycosin as marker compounds of Astragali radix extracts were optimized by HPLC analysis using a Thermo Hypersil column ($4.6{\times}250mm$, $5{\mu}m$) with the gradient elution of water and acetonitrile as the mobile phase at the flow rate of $0.8mLmin^{-1}$ and a detection wavelength of 230nm. The HPLC/UV method was applied successfully to the quantification of two marker compounds in Astragali radix extracts after validation of the method with the linearity, accuracy and precision. The contents of calycosin-7-O-${\beta}$-D-glucoside and calycosin in 50% ethanol extracts by reflux extraction were significantly higher as $1,700.3{\pm}30.4$ and $443.6{\pm}8.4{\mu}g-1$, respectively, comparing with those in other extracts. The results indicate that the reflux extraction with 50% ethanol at $85^{\circ}C$ is optimal for the extraction of Astragali radix, and the established HPLC method are very useful for the evaluation of marker compounds in Astragali radix extracts to develop the health functional material from Astragali radix.

• Journal of The Korean Society of Clinical Toxicology
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• v.17 no.2
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• pp.47-57
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• 2019

Purpose: Osmolar gap (OG) has been used for decades to screen for toxic alcohol levels. However, its reliability may vary due to several reasons. We validated the estimated ethanol concentration formula for patients with suspected poisoning and who visited the emergency department. We examined discrepancies in the ethanol level and patient characteristics by applying this formula when it was used to screen for intoxication due to toxic levels of alcohol. Methods: We retrospectively reviewed 153 emergency department cases to determine the measured levels of toxic ethanol ingestion and we calculated alcohol ingestion using a formula based on serum osmolality. Those patients who were subjected to simultaneous measurements of osmolality, sodium, urea, glucose, and ethanol were included in this study. Patients with exposure to other toxic alcohols (methanol, ethylene glycol, or isopropanol) or poisons that affect osmolality were excluded. OG (the measured-calculated serum osmolality) was used to determine the calculated ethanol concentration. Results: Among the 153 included cases, 114 had normal OGs (OG≤14 mOsm/kg), and 39 cases had elevated OGs (OG>14). The mean difference between the measured and estimated (calculated ethanol using OG) ethanol concentration was -9.8 mg/dL. The 95% limits of agreement were -121.1 and 101.5 mg/dL, and the correlation coefficient R was 0.7037. For the four subgroups stratified by comorbidities and poisoning, the correlation coefficients R were 0.692, 0.588, 0.835, and 0.412, respectively, and the mean differences in measurement between the measured and calculated ethanol levels were -2.4 mg/dL, -48.8 mg/dL, 9.4 mg/dL, and -4.7 mg/dL, respectively. The equation plots had wide limits of agreement. Conclusion: We found that there were some discrepancies between OGs and the calculated ethanol concentrations. Addition of a correction factor for unmeasured osmoles to the equation of the calculated serum osmolality would help mitigate these discrepancies.

• Korean Journal of Food Science and Technology
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• v.30 no.2
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• pp.293-298
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• 1998

Allithiamine was synthesized when thiamine was mixed with fresh garlic extract made with ethanol at a alkali medium. Allithiamine was isolated and purified using solvents such as ethyl acetate, diethyl ether and benzene. Purified allithiamine was identified by determination of melting point, elemental analyzer and LC/Thermospray/Mass-spectrometer. On the other hand, synthetic conditions of allithiamine from fresh garlic, pH, temperature and ratio of garlic to ethanol were investigated. Synthetic rates of allithiamine under alkali conditions were rapidly increased while those under acidic conditions very slowly increased. The synthetic rates of allithiamine increased as temperature increased, but decreased above $70^{\circ}C$ as reaction time increased. There was no significant difference in synthetic rate of allithiamine when garlic was mixed above 4 times of ethanol. Therefore, optimum condition of pH, temperature and ratio of garlic to ethanol for synthesis of allithiamine were 8, $60^{\circ}C$ and 1 : 4, respectively.

• Analytical Science and Technology
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• v.12 no.3
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• pp.218-223
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• 1999

A single use, screen-printed sensor for the measurement of liquid phase ethanol was developed and its electrochemical performance was investigated. Disposable type edthanol sensor was fabricated by serially screen printing the carbon paste, silverd pasted and insulator inlon a polyester substrate to pattern working and reference electrode sites and electrical contact. Alcohol dehydrogenase(ADH) or alcohol oxidase(AOD) together with appropriate electron transfer mediators was immobilized on the working electrode. To improve the sensitivity and reproducibility of carbon paste electrode, some pretreatment procedures were applied and their resultant electrochemical performance was examined. The disposable type electrochemical ethanol sensor developed in this study conveniently determines the ethanol in liquid samples such as blood and in fermentation process.