• Proceedings of the PSK Conference
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• 2003.10b
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• pp.174.3-175
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• 2003

1-and 2-Bromopropane were reported as the causative agents for reproductive toxicity and immunotoxicity. The glutathione (GSH) metabolites resulting from in vitro treatment of 1- and 2-bromopropane were detected, identified and characterized. For the facile identification, expected GSH metabolites rormed by 1- and 2-bromopropane were chemically synthesized as reference materials (positive controls) and characterized by $^1H$-NMR, $^13C$-NMR, HPLC and LC/MS/MS. The treatment of GSH and S-9 fraction with 1- or 2-bromopropane at a physiological condition (pH 7.4, $37^\times$) for 1hr produced GSH metabolites, which were identified by UV, HPLC and ESI LC/MS/MS analyses. (omitted)

• YAKHAK HOEJI
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• v.55 no.4
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• pp.289-294
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• 2011

Illegal addition of steroids into cosmetics, ointments or drugs have been increased and their careless usage induced detrimental effect on health. We developed simultaneous analytical method using TLC, HPLC and LC/MS for the identification of 40 corticosteroids. 34 corticosteroids were well separated in HPLC with isocratic mode and remaining 6 drugs were also separated with gradient mode. All of the 40 corticosteroids were detected in negative mode in LC/MS. Halcinonide, prednisolone, triamcinolone acetonide and methylprednisolone hemisuccinate were detected in real samples.

• Bulletin of the Korean Chemical Society
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• v.34 no.9
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• pp.2567-2568
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• 2013

• Journal of Food Hygiene and Safety
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• v.31 no.1
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• pp.15-20
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• 2016

Malachite green was measured in 200 freshwater fish collected from local markets in Seoul using HPLC-DAD and LC-MS/MS. LC-MS/MS method was validated by linearity, accuracy, precision and limits of detection and quantification according to the CODEX's recommendation and HPLC-DAD method was applied according to the Food Code. Malachite green levels above the quantification limit of the LC-MS/MS were determined 18.5% (37) but just 1 fish was shown to contain malachite green by HPLC-DAD. Of 83 domestic fish, 21 fish were detected malachite green (25.3%). Of 117 fish from China, just 16 fish were detected malachite green (13.4%). In detection rate by species carp (35.0%), Crucian carp (30.4%), cat fish (28.0%), Korean bull head (23.8%), snake head (20.0%), eel (10.5%) and loach (7.8%) were in order. Especially, fish collected at summer were shown to contain malachite green frequently; the detection rate was 54.8%.

• YAKHAK HOEJI
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• v.52 no.6
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• pp.446-451
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• 2008

A high-performance liquid chromatography (HPLC) with diode array detector (DAD) and electrospray ionization mass spectrometry (ESI-MS) was established for the simultaneous determination of chlorogenic acid (1), sweroside (2), luteolin-7-O-glucoside (3), (E)-aldosecologanin (4) and 3,5-dicaffeoylquinic acid (5) from Lonicera joponica flower buds. The optimal chromatographic conditions were obtained on an ODS column (5 ${\mu}m$, 4.6${\times}$150 mm) with the column temperature $25^{\circ}C$. The mobile phase was composed of (A) water with 0.1% formic acid and (B) acetonitrile with 0.1% formic acid using a gradient elution, the flow rate was 0.3 ml/min. Detection wavelength was set at 250 nm. All calibration curves showed good linear regression ($r^2$>0.994) within test ranges. The developed method provided satisfactory precision and accuracy with overall intra-day and inter-day variations of 0.05${\sim}$1.95% and 0.15${\sim}$2.26%, respectively, and the overall recoveries of 97.71${\sim}$103.65% for the five compounds analyzed. The verified method was successfully applied to quantitative determination of the three types (phenolic compounds, iridoids and flavonoids) of bioactive compounds in 21 commercial L. japonica flower buds samples from different markets in Korea and China. The analytical results demonstrated that the contents of the five analytes vary significantly with sources.

• Journal of Ginseng Research
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• v.43 no.1
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• pp.27-37
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• 2019

Background: The structural conversions in ginsenosides induced by steaming or heating or acidic condition could improve red ginseng bioactivities significantly. In this paper, the chemical transformations of red American ginseng from fresh Panax quinquefolium L. under steaming were investigated, and the possible mechanisms were discussed. Methods: A method with reversed-phase high-performance liquid chromatography coupled with linear ion trap mass spectrometry ($HPLC-MS^n$)-equipped electrospray ionization ion source was developed for structural analysis and quantitation of ginsenosides in dried and red American ginseng. Results: In total, 59 ginsenosides of protopanaxadiol, protopanaxatriol, oleanane, and ocotillol types were identified in American ginseng before and after steaming process by matching the molecular weight and/or comparing $MS^n$ fragmentation with that of standards and/or known published compounds, and some of them were determined to be disappeared or newly generated under different steaming time and temperature. The specific fragments of each aglycone-type ginsenosides were determined as well as aglycone hydrated and dehydrated ones. The mechanisms were deduced as hydrolysis, hydration, dehydration, and isomerization of neutral and acidic ginsenosides. Furthermore, the relative peak areas of detected compounds were calculated based on peak areas ratio. Conclusion: The multicomponent assessment of American ginseng was conducted by $HPLC-MS^n$. The result is expected to provide possibility for holistic evaluation of the processing procedures of red American ginseng and a scientific basis for the usage of American ginseng in prescription.

• Applied Biological Chemistry
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• v.50 no.1
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• pp.72-76
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• 2007

In order to examine the biofunctions of glycosylceramide which is representative of sphingolipid, monoglycosylceramide (cerebroside) was isolated from rice bran extract. Crude glycosylceramides were isolated in large quantities and promptly by flash system column chromatography from rice bran extract, and purified by normal-phase HPLC using an evaporative light-scattering detector. One major cerebroside was obtained by HPLC used as an eluent consisting of chloroform, methanol and water (99:11:1, v/v/v), and the constituents were analyzed by MALDI/TOF-MS, FAB-MS, GC and 600 MHz $^1$H-NMR. The component sugar was estimated to be glucose. In the ceramide, the fatty acid component consist was 2-hydroxy arachidic acid. The long-chain base component was sphinga-4,8-dienine.

• The Korean Journal of Pesticide Science
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• v.2 no.3
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• pp.79-84
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• 1998

Tandem HPLC and atmospheric pressure chemical ionization(APcI) LC/MS method was used for the determination and confirmation of carbendazim residues in soybean sprout. Fluorescence(FL) detector was connected in tandem with the ultraviolet(UV) detector for dual detection of the carbendazim residue at the excitation and emission wavelength of 280 nm and 310 nm, respectively. The limit of detection for carbendazim was $0.1{\mu}g/kg$ sample. Recoveries of carbendazim from fortified soybean sprout at 0.5, 1.0 and 2.0 ppm were averaged 89.1%. Mass spectrometry using a APcI source confirmed the carbendazim residue in the soybean sprout sample. Fragmentation pattern on the APcI LC/MS spectrum of carbendazim was simpler than that from electron impact(EI) mass spectrum. Carbendazim produced 3 major ions including m/z 133, m/z 159 and m/z 191($M^{+}$). This method was sensitive enough to provide reliable and reproducible results for practical applications.

• Korean Journal of Plant Resources
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• v.33 no.4
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• pp.237-244
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• 2020

The objective of this study was to identify and characterize fibrinolytic compound from Cornus officinalis. Cornus officinalis. Hot water extract was fractionated into hexane, chloroform, ethyl acetate, butanol, and water fractions. Assays for fibrinolytic activity indicated that only the ethyl acetate fraction had significant efficacy at 1.36 plasmin units/mL. Isolation of fibrinolytic compound was carried out on Amberlite IRA-400, Sephadex LH-20 and active charcoal column chromatography. HPLC analysis of the purified fibrinolytic compound showed retention time (RT) same as authentic malic acid. LC / MS / MS in negative mode showed the same peak at m/z 133, confirming that the purified compound was malic acid with a molecular weight 134 Da. The compound showed fibrinolytic activity of 0.69 plasmin units/mL, 14.62% of thrombin inhibitory activity, 6.42% of antioxidative activity, and 17.28% of α-glucosidase inhibitory activity. The purified compound hydrolyzed γ subunits of human fibrinogen. In conclusion, malic acid isolated from Cornus officinalis might have potential to be developed as ingredient for biofunctional foods to prevent cardiovascular diseases.

• Natural Product Sciences
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• v.25 no.1
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• pp.49-58
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• 2019

Eleven steroid hormones (SHs: androstene-3,17-dione, estrone, ${\beta}$-estradiol, ${\alpha}$-estradiol, testosterone, dehydroepiandrosterone, $17{\acute{a}}$-hydroxyprogesterone, medroxyprogesterone, megestrol acetate, progesterone, and androsterone) were detected from New Zealand deer (Cervus elaphus var. scoticus) velvet antler (NZA, 鹿茸 ). A method for the quantification of eleven SHs was established by using ultraperformance liquid chromatography (UPLC)-MS/MS. The linearities ($R^2$ > 0.991), limits of quantification (LOQ values, 0.3 ng/mL to 23.1 ng/mL), intraday and interday precisions (relative standard deviation: RSD < 2.43%), and recovery rates (97.3% to 104.6%) for all eleven SHs were determined. In addition, a method for the quantification of three 7-oxycholesterols (7-O-CSs: 7-ketocholesterol, $7{\alpha}$-hydroxycholesterol, and $7{\beta}$-hydroxycholesterol) in the NZA was established by using an HPLC-photodiode array (PDA) method. The linearities ($R^2$ > 0.999), LOQ values (30 ng/mL to 350 ng/mL), intraday and interday precisions (RSD < 1.93%), and recovery rates (97.2% to 103.5%) for the three 7-O-CSs were determined. These quantitative methods are accurate, precise, and reproducible. As a result, it is suggested that the five steroid compounds of androstene-3,17-dione, androsterone, 7-ketocholesterol, $7{\alpha}$-hydroxycholesterol, and $7{\beta}$-hydroxycholesterol could be marker steroids of NZA. These methods can be applied to quantify or standardize the marker steroids present in NZA.