• Asian-Australasian Journal of Animal Sciences
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• v.7 no.4
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• pp.509-512
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• 1994

High performance liquid chromatography (HPLC) analysis was applied for determination of guanine plus cytosine (G + C) contents of DNA of Butyrivibrio fibrisolvens. By values of G + C contents, a reference strain and 20 wild strains of B. fibrisolvens were classified into at least two distinct subgroups, i.e. G + C contents of 18 strains were 38-40 mol% and those of 3 strains including the reference strain were 43-45 mol%. Clear relationships were not observed between G + C contents and biological properties of 21 strains of B. Fibrisolvens.

• Analytical Science and Technology
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• v.13 no.3
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• pp.399-402
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• 2000

To determine the concentrations of microcystins present in lake water or in tap water using high performance liquid chromatography, it is necessary to concentrate a large volume of water samples (about 20 L) into very small volume (0.1-0.3 mL). Concentration can be conveniently done when disc type solid phase extraction (SPE) apparatus is used. Using this apparatus we have investigated the recovery rates of three kinds of microcystins, RR, YR, LR. The recovery rates were relatively low and the reproducibilities were not good either. It is expected, however, that the appropriate selection of the disc conditioning and eluting solvents and reproducible reconcentration process after SPE will improve both the recovery rates and the reproducibilities.

• Proceedings of the PSK Conference
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• 2003.04a
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• pp.304.2-305
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• 2003

A simple and rapid method for the determination of theophylline (THP) in human serum was developed by a high performance liquid chromatography/UV detector and applied to pharmacokinetic study of THP in human volunteers. ${\beta}$-Hydroxyethyltheophylline as internal standard was added to 200 ${\mu}\ell$ of human serum and the mixture was centrifuged at 13000 rpm for 10 min. (omitted)

• Proceedings of the PSK Conference
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• 2003.04a
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• pp.279.2-280
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• 2003

A simple and accurate reverse-phase high performance liquid chromatography (HPLC) coupled with photodiode array was developed for the determination of dextromethorphan(DM) and its metabolite dextrorphan(DX) in human urine. Chromatographic separation was accomplished on a cyano analytical column at 220 nm using a mobile phase containing 25 mM triethylammonium phosphate buffer(PH 3.0) in a 0-70％ ACN gradient and triazolam(TZ) was used as internal standard(I.S). (omitted)

• Korean Journal of Veterinary Service
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• v.23 no.1
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• pp.1-8
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• 2000

This study was carried out to simultaneous determination of penicillin G and chloramphenicol in livestock products by HPLC. The results obstained were as follows; 1. Penicillin G and chloramphenicol were analyzed by HPLC on symmetry $C_{18}$ column with acetonitrile-0.1 M phosphate buffer containing 0.0157 M thiosulfate (25 : 75) as mobile phase at UV 325nm and 280nm, respectively. 2. Samples were applied to a SeP-Pak $C_{18}$ cartridge, from which eluted penicillin derivatized with 2 M 1,2,4-triazole containing 0.001 M mercuric chloride. 3. The average recovery rates of penicillin G and chloramphenicol were 81.8% and 80.3%, respectively, and the detection limits were 5 ppb (5$\mu\textrm{g}$/kg: 7.9IU/kg) for penicillin G and chloramphenicol in porcine and bovine muscle.

• Korean Journal of Pharmacognosy
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• v.11 no.2
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• pp.75-80
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• 1980

The decoctions and extracts were prepared on the traditionally prescribed four kinds (Kejigamcho-tang, Kejibanha-tang, Keji-tang, Kejiinsam-tang) of preparations containing Cinnamoni Raulus. The contents of cinnamic acid and cinnamic aldehyde in these preparations were determined by high performance liquid chromatography using reverse phase partition column, and 12% MeOH as eluting solvent. The sample was determined using the two wave length, 254nm and 280nm. This method was sucessfully applied to the analysis of cinnamic acid and cinnamic aldehyde of various preparations containing Cinnamons.

• Korean Journal of Pharmacognosy
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• v.21 no.3
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• pp.239-241
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• 1990

A new method for quantitative determination of byakangelicin in Angelicae dahuricae Radix by high performance liquid chromatography was established. A reversed-phase system with a ${\mu}Bondapak$ $C_{18}$ column using THF : dioxane : MeOH : HAc : 5% $H_3PO_4$ : $H_2O$=72.5 : 62.5 : 25 : 10 : 1 : 329 as a mobile phase was developed. Byakangelicin together with ter-O-byakangelicin and oxypeucedanin methanolate, and isooxypeucedanin as an internal reference were detected at 350 nm and the analysis was successfully carried out within 30 min.

• Korean Journal of Veterinary Service
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• v.21 no.3
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• pp.261-266
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• 1998

A method for the determination of noboviocin in milk was presented by high performance liquid chromatography(HPLC). The novobiocin in the spiked sample was extracted with methanol and evaporated under vacuum. After evaporating, the residue was mixed with distilled water for 2$m\ell$, filtrates with 0.45$\mu\textrm{m}$ acrodisc was injected into HPLC. The results obtained were as follows ; 1. The calibration curve of novobiocin was showed constantly linear(r 0.999) in the range of 100~500ng/$m\ell$. 2. The mean recovery rate of novobiocin from the spiked milk sample were 88~98%. 3. The coefficients of variation were 2.6~5.8% 4. The lowest detectable limit of novobiocin was 25ppb.

• Analytical Science and Technology
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• v.5 no.3
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• pp.339-343
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• 1992

The content of lysophosphatidyl choline (LPC) in wheat starch lipids from six cultivar representing three classes of wheat was determined by a high performance liquid chromatography using UV-detection (HPLC-UV). The HPLC-UV assay had a sensitivity of LPC concentrations above $5{\mu}g/50{\mu}l$ and required 80 minutes per chromatogram.

• Korean Journal of Pharmacognosy
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• v.30 no.3
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• pp.328-331
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• 1999

A new method for quantitative determination of p-methoxycinnamic acid in Scrophulariae radix by high performance liquid chromatography was established. A reversed-phase system with SPHERI-5 RP-18 5 micron $(250\;{\times}\;4.6\;mm)$ column using TFA (0.05%) and acetonitrile as a mobile phase was developed. p-Methoxycinnamic acid and N-(p-methoxycinnamoyl)-p-aminophenol as an internal reference were detected at 310 nm and the analysis was successfully carried out within 50 min.