• Bulletin of the Korean Chemical Society
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• v.34 no.8
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• pp.2413-2418
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• 2013

Forensic and legal medicine require reliable data to indicate excessive alcohol consumption. Ethanol is oxidatively metabolized to acetate by alcohol dehydrogenase and non-oxidatively metabolized to ethyl glucuronide (EtG), ethyl sulfate (EtS), phosphatidylethanol, or fatty acid ethyl esters (FAEE). Oxidative metabolism is too rapid to provide biomarkers for the detection of ethanol ingestion. However, the non-oxidative metabolite EtG is a useful biomarker because it is stable, non-volatile, water soluble, highly sensitive, and is detected in body fluid, hair, and tissues. EtG analysis methods such as mass spectroscopy, chromatography, or enzyme-linked immunosorbent assay techniques are currently in use. We suggest that nuclear magnetic resonance (NMR) spectroscopy could be used to monitor ethanol intake. As with current conventional methods, NMR spectroscopy doesn't require complicated pretreatments or sample separation. This method has the advantages of short acquisition time, simple sample preparation, reproducibility, and accuracy. In addition, all proton-containing compounds can be detected. In this study, we performed $^1H$ NMR analyses of urine to monitor the ethanol and EtG. Urinary samples were collected over time from 5 male volunteers. We confirmed that ethanol and EtG signals could be detected with NMR spectroscopy. Ethanol signals increased immediately upon alcohol intake, but decreased sharply over time. In contrast, EtG signal increased and reached a maximum about 9 h later, after which the EtG signal decreased gradually and remained detectable after 20-25 h. Based on these results, we suggest that $^1H$ NMR spectroscopy may be used to identify ethanol non-oxidative metabolites without the need for sample pretreatment.

• Korean Journal of Food Science and Technology
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• v.30 no.2
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• pp.266-271
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• 1998

In order to find a novel antioxidant source from nature, the comparison of antioxidative activity was carried out through the CDM(conductometric determination method) with various crude drugs on palm oil, lard and soybean oil. After the preliminary experiment, we concluded that the turmeric (Curcumae Rhizoma) ethanol extract has the strongest antioxidative activity among the ten crude drugs. In case of over 0.05% of concentration turmeric ethanol extract, it has more activity than others athough the turmeric ethanol extract has similar antioxidative activity to tocopherol and rosemary extract up to 0.05% of concentration. The turmeric ethanol extract of 0.01% was more effective in lard (AI=4.59) than in palm oil (AI=1.57) and ineffective in soybean oil. When turmeric ethanol extract was added to various kind of fatty acid methyl esters at 0.05% and 0.1% respectively, the antioxidative index(AI) on oleic acid methyl ester was greatly increased, whereas the antioxidative index on linoleic acid methyl ester was decreased.

• Bulletin of the Korean Chemical Society
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• v.21 no.11
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• pp.1115-1118
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• 2000

Specimens were cured by using a 1 mm (thickness) ${\times}$5 mm (diameter) teflon mold, and were immersed in artificial saliva and in 75% ethanol for 1, 7, 14, 21 and 28 days in order to quantify and to identify toxic components and to determine any degra dation byproducts of Bis-GMA that might be released from five commercially available resin-based dental sealants. In artificial saliva, the only released component was triethylene glycol dimethacylate (TEGDMA). In 75% ethanol, TEGDMA, 2,2-bis[4-(2-hydroxy-3-methacryloyloxypropoxy) phenyl]propane (Bis-GMA) and urethane dimethacrylate (UDMA) were released highly at the initial stage, indicating that the amount of component released is not linearly correlated with the immersion time. The amount of released TEGDMA was found to be much higher in 75% ethanol than in artificial saliva. Importantly, bisphenol-A (BPA) was detected from all the uncured sealants tested, suggesting that all the sealants tested contain BPA as a contaminant.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.3
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• pp.353-358
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• 2006

Flavonoid and limonoid compounds were determined by HPLC on the methanol and ethanol extracts from citron seeds. The quantities of the compounds in these categories were higher in the ethanol extract than methanol extract. The types of these compounds were detected in larger numbers in the ethanol extract. The content of limonin was the largest in both methanol and ethanol extract among the detectable compounds ; 140.34 mg/100g and 170.98 mg/100g, respectively, and the contents of other compounds, caffeic acid, naringin, lutin, nomilin, were found in large amount in this order. The molecular weights of forty two compounds in ethanol extract were determined with mass spectrums and extracted ion current chromatograms by HPLC/MS.

• Journal of Pharmaceutical Investigation
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• v.21 no.3
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• pp.171-177
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• 1991

A reverse-phase, ion-pair high performance liquid chromatographic (HPLC) method for the simultaneous quantative determination of pyridostigmine and its hydrolytic product, 3-hydroxy-N-methylpyridinium (HMP), is descrihed, The assay of pyridostigmine and HMP was linear in the range of amount from 24 to 60 mg/tablet and from 2.4 to 12.0 mg/tablet, respectively, with coefficient of variation (C.V.) of 0.05-0.12% (n=7) and 0.25-0.52% (n=5), respectively, and applicable conveniently even in the case of the mixture of pyridostigmine and HMP. Meanwhile, the conventional UV method gave inaccurate results for the aged pyridostigmine tablets. In the extraction of pyridostigmine from tablets prior to be assayed by HPLC, methanol was found to be more effective than ethanol or distilled water. Multiple extraction (four times) with methanol resulted in the full recovery of pyridostigmine, whereas ethanol gave 95% recovery even after four times extraction. Based on these results. the present method would be very useful for the accurate determination of pyridostigmine in the aged pyridostigmine tablets.

• Korean Journal of Pharmacognosy
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• v.37 no.1 s.144
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• pp.33-36
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• 2006

The quantitative analytical method for the content of dioscin in Dioscorea rhizoma using a high performance liquid chromatography(HPLC) system was established for its quality control. After extracting Discorea rhizoma flour with ethanol, dioscin was separated though an ODS column with a flow rate of 1.0ml/min of acetonnitril-methanol-0.01 M phosphate buffer (pH 5.0)(6:3:1, v/v%), and the amount of dioscin was detected at 210nm. Relation time of dioscin in HPLC chromatogram were about $7.45{\pm}0.34\;min$ and calibration curve showed good linearity at concentrations from 0.1 to 2.0 mg/ml of dioscin. When 5 commercial Dioscorea rhizoma flours were analyzed by HPLC, the peak for dioscin was well separated from others in ethanol extract of Dioscorea rhizoma, and the amount of dioscin was in the range from 0.076 to 0.142(w/w)%.

• Archives of Pharmacal Research
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• v.22 no.3
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• pp.294-299
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• 1999

Precolumn orthophthaldehyde (OPA) labeling method of sphingoid bases, sphingosine and sphinganine, was investigated to obtain high fluorescent detectability. In order to improve the fluorescent yield, we investigated the optimal solubility of sphingoid bases for five pre-incubation solvents by incorporating the heating procedure before OPA derivatization. The pre-incubation in ethanol prominently increased the fluorescent peak height of OPA derivative for each sphingoid bases in high performance liquid chromatography. About tenfold increase of detectability was archived by pre-incubating lipid extracts pellets in ethanol at $60^{\circ}C$ for 30 min. Optimal derivatization was performed in 30 min at ambient temperature and the fluorescent intensity of OPA derivative was stable for two weeks at $4^{\circ}C$. The detection limit of sphingosine was 0.1 pmol as injected amount. This method was applied to the determination of cellular sphingosine and sphinganine in various human lung cancer cells. This OPA procedure was prospective to be useful for quantitating the amount of sphingoid bases in other cancer cells.

• Bulletin of the Korean Chemical Society
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• v.32 no.8
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• pp.2727-2731
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• 2011

A new method for the determination of josamycin has been developed based on quenching of the fluorescence of 3-mercaptopropionic acid-capped CdTe quantum dots (MPA-CdTe QDs) by josamycin in ethanol. Reaction time, interfering substances on the fluorescence quenching, and mechanism of the interaction of CdTe QDs with josamycin were investigated. Under optimum conditions, the relative fluorescence intensity was linearly proportional to the concentration of josamycin between 12.0 and 120.0 ${\mu}g\;mL^{-1}$ with a correlation coefficient of 0.9956 and a detection limit of 2.5 ${\mu}g\;mL^{-1}$. The proposed method was successfully applied to commercial tablets, and the results were satisfactory, i.e. consistent with those of high-performance liquid chromatography (HPLC).

• Membrane Journal
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• v.7 no.2
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• pp.65-74
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• 1997

Pervaporation pilot tests for obtaining the anhydrous ethanol, which is an automobile fuel additive for reducing air pollution, were carried out in the production field of fermented ethanol by using a PVA composite membrane. In the pervaporation dehydration of the ethanol/water azeotropic mixture, the membrane performance is concluded to be enhanced with the heating temperature of feed. In the determination of the permeate condensation temperature from the viewpoint of energy cost, an Optimal temperature was found to be near $0{\circ}C$. The results on the dehydration of fermented ethanol were similar to those of synthetic ethanol, which indicates that the pervaporation performance is not influenced by impurities contained in the ethanol to be dehydrated. From a comparison of calculated energy needed in the system and measured value in the pilot test, it is confirmed that the latent heat for vaporization of permeant on the permeate side of membrane is supplied from the feed.

• Preventive Nutrition and Food Science
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• v.16 no.1
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• pp.29-36
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• 2011

The purpose of this study was to investigate the phytochemical contents and biological activities, including $\alpha$-glucosidase inhibitory activity and antioxidant activity, from the fruits of Elaeagnus multiflora using different solvent systems. The 50% ethanol extract of this species showed the most potent $\alpha$-glucosidase inibitory activity (88.5%) at a concentration of 1 mg/mL. Moreover, this extract also displayed the strongest antioxidant activity in each assay, showing 96.3% in DPPH scavenging activity, 98.2% in ABTS scavenging activity, and 2.5% in reducing power. The highest total phytochemical contents, including flavan-3-ols, phenolic acids, and flavonoids, were observed in the 50% ethanol extract. Interestingly, flavan-3-ols (3.150 mg/g) were detected at a significantly higher total content than those of phenolic acids (0.380 mg/g) and flavonoids (not detected). Additionally, the contents of individual phytochemicals showed remarkable differences, especially the epicatechin gallate (2.008 mg/g) and gallic acid (0.099 mg/g), which were the predominant constituents of each phytochemical type. Therefore, our results suggest that the 50% ethanol extract of E. multiflora fruits has strong biological activities, which are correlated with high phytochemical contents.