• Analytical Science and Technology
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• v.24 no.4
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• pp.266-274
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• 2011

Using a Hitachi LaChrom Ultra 2000U, a reverse phase ultra high performance liquid chromatography (u-HPLC) method was developed for the rapid quantification of 14 PAHs in foods. The proposed method for PAH analysis is based on solid phase extraction (SPE) cartridges; the determination was carried out by u-HPLC with fluorimetric detection. The method was very sensitive; PAH concentration levels were in a low ${\mu}g$/kg range and could be detected and quantified. Six samples of food were analyzed. Among PAHs, PHE was found in most of samples, the concentration ranging from 2.5 to 19.9 ${\mu}g$/kg. The contents of benzo[c]fluorine (BCL), pyrene (PYR), benzo[a]anthracene (BaA), chrysene (CHR), benzo[b]fluoranthene (BbF), benzo[k]fluoranthene (BkF) were low at the '${\mu}g$/kg' level or were less than LOD.

• Mycobiology
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• v.42 no.3
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• pp.296-300
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• 2014

We selected Pleurotus ostreatus from among several edible mushrooms because it has high anti-gout xanthine oxidase (XOD) inhibitory activity. The maximal amount of XOD inhibitor was extracted when the Pleurotus ostreatus fruiting body was treated with distilled water at $40^{\circ}C$ for 48 hr. The XOD inhibitor thus obtained was purified by Sephadex G-50 gel permeation chromatography, ultrafiltration, $C_{18}$ solid phase extraction chromatography and reverse-phase high-performance liquid chromatography with 3% of solid yield, and its XOD inhibitory activity was 0.9 mg/mL of $IC_{50}$. The purified XOD inhibitor was a tripeptide with the amino acid sequence phenylalanine-cysteine-histidine and a molecular weight of 441.3 Da. The XOD inhibitor-containing ultrafiltrates from Pleurotus ostreatus demonstrated dose-dependent anti-gout effects in a Sprague-Dawley rat model of potassium oxonate-induced gout, as shown by decreased serum urated levels at doses of 500 and 1,000 mg/kg, although the effect was not as great as that achieved with the commercial anti-gout agent, allopurinol when administered at a dose of 50 mg/kg.

• Archives of Pharmacal Research
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• v.14 no.2
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• pp.99-102
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• 1991

A hight performance liquid chromatographic methods was developed for the seperation and determination of seven alkaloids in "sanjoin" (the seeds of Zizyphus jujuba Rhamnaceae), a plant with potent sedative activity. A reverse phase system of Lichrosorb RP-Select B column and 0.05 M potassium phosphate buffer (pH = 3.5)-acetonitrile with gradient elution was employed. Two known alkaloids, juzirine and lysicamine, were newly isolated fom "sanjoin"."sanjoin".oin&".ot;.

• Analytical Science and Technology
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• v.19 no.6
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• pp.519-528
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• 2006

An analytical method for the determination of thyroid hormones in urine samples has been studied by using solid-phase extraction and high-performance liquid chromatography/diode array detector/electro-spray mass spectrometry. Seven thyroid hormones were successfully separated by gradient elution on the reverse phase Hypersil ODS column (4.6 mm I.D., 100 mm length, particle size $5{\mu}m$) with ammonium formate buffer and acetonitrile, and UV spectra and mass fragment could be confirmed. The extraction recoveries of thyroid hormones in the urine samples (pH 3) were in the range of 89.0-113.1% with solid-phase extraction by C18, followed by elution with 4 ml of methanol/ammonium hydroxide (9 : 1). The calibration curves showed good linearity with the correlation coefficients ($r^2$) varying from 0.992 to 0.998 and the detection limits of all analytes were obtained in the range of 2-4 ng/ml (3.8-13.0 pmol/ml).

• Korean Journal of Pharmacognosy
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• v.43 no.3
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• pp.250-256
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• 2012

In order to extract the curcuminoid such as curcumin, demethoxycurcumin (DMC), and bisdemethoxycurcumin (BDMC) in turmeric (Curcuma longa), solvent extraction methods (dipping and ultrasonic extraction method) and solid-phase extraction (SPE) were used. RP-HPLC (reverse-phase high-performance liquid chromatography) and TLC (thin-layer chromatography) were used for identification and analysis the three curcuminoid. From the experimental results, it is evident that the percentage of curcuminoid extracted from turmeric by ultrasonic extraction method was higher than dipping method. The percentage of curcumin extracted from turmeric by pure methanol was higher than any aqueous methanolic composition. Moreover, the total peak area of three curcuminoid was above 92% in RP-HPLC using solid-phase extraction. These results will form a database for investigating the constituents of natural products and the resources of pharmaceutical, nutrition, and cosmetic products.

• Food Science and Biotechnology
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• v.17 no.3
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• pp.489-494
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• 2008

In order to develop a potent antidementia $\beta$-secretase inhibitor from phytochemicals, $\beta$-secretase inhibitory activities of extracts from many medicinal plants and herbs were determined. Water extracts from Rubus coreanus showed the highest $\beta$-secretase inhibitory activity of 84.5%. After purification of the $\beta$-secretase inhibitor from R. coreanus using systematic solvent extraction, ultrafiltration, Sephadex G-10 column chromatography, and reverse-phase high performance liquid chromatography (HPLC), a purified $\beta$-secretase inhibitor with $IC_{50}$ inhibitory activity of $6.3{\times}10^3\;ng/mL$ ($1.56{\times}10^{-6}\;M)$ was obtained with a 0.08% solid yield. The molecular mass of the purified $\beta$-secretase inhibitor was estimated to be 576 Da by liquid chromatography-mass spectrometry (LC-MS) and $\beta$-secretase inhibitor also is a new tetrapeptide with the sequence Gly-Trp-Trp-Glu. The purified $\beta$-secretase inhibitory peptide inhibited $\beta$-secretase non-competitively and also show less inhibition on trypsin, however no inhibition on other proteases such as $\alpha$-secretase, chymotrypsin, and elastase.

• Journal of the Korean Society of Food Science and Nutrition
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• v.20 no.3
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• pp.225-232
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• 1991

A Study was carried out to elucidate the triglyceride compositions of the red pepper seed oils harvested from two different areas. The oil was extracted from the red pepper seed with nhexane. Each triglyceride of the oil was separated by thin layer chromatography (TLC) and fractonated by reverse phase high performance liquid chromatography (HPLC) on the basis of acyl carbon numbers, and partition number group(PN) and fatty acid composition of triglyceride were analyzed by gas liquid chromatography (GLC). From the results, it was found that the red pepper seed oils of the Chungsong and Youngyang areas consisted of 14 and 18 kinds of triglycerides, respectively. The red pepper seed oil of the Chungsong area consisted of (C18:2, C18:2, C18:2=41.0%), (C16:0, C18:2, C18:2=37.1%), and that of the Youngyang area consisted of (C18:2, C18:2, C18:2=41.0%), (C16:0, C18:2, C18:2=36.3%) and (C16:0, C16:2, C18:2=8.4%), as the major triglycerides.

• Proceedings of the PSK Conference
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• 2003.10b
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• pp.223.1-223.1
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• 2003

D-Amygdalin and its conversion product, neoamygdalin, were clearly separated on reverse-phase column chromatography by an optimized eluent of 10 mM sodium phosphate buffer (pH 3.5) containing 8.5% acetonitrile. Linearity for analyzing D-amygdalin and neoamygdalin was observed in the range from 0.05 to 0.5 mM. The detection limits for D-amygdalin and neoamygdalin were ca. 5 uM per injected amount. When extracting amygdalin from a whole piece of Armeniacae Semen in the boiling aqueous solution, there was almost no influence of emulsin; it resulted in higher extraction yield. (omitted)

• Proceedings of the PSK Conference
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• 2002.10a
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• pp.241.1-241.1
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• 2002

Tolperisone hydrochloride is used as a muscle relaxant. Very few assay methods of tolperisone were reported. such as potentiometry. spectrophotometry and high performance thin layer chromatography. In addition. there is no report related to HPLC method to determine the tolperisone level in biological sample. In this study, A very sensitive reverse phase high performance liquid chromatographic (RP-HPLC) method for the determination of tolperisone HCI in plasma has been developed. (omitted)

• Science of Emotion and Sensibility
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• v.14 no.4
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• pp.531-536
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• 2011

The precise measurement of human emotion is of pivotal importance in the field of emotion science. Based on the perspective of psychoneuroimmunoendocrinology, human emotion is now considered to be measurable by body fluid. The biological molecule cortisol, which is known for the stress hormone, has been widely investigated to help researchers to estimate the stress loaded on human body. Until now, several measurement techniques such as High Performance Liquid Chromatography (HPLC), fluorometric assay, and reverse phase chromatography have been developed. However, since these measurements are expensive, take relatively long time for an operation, and they are not portable, they are not appropriate for POCT (point of care testing). In this paper we demonstrate the performance of a miniaturized-microwave resonant device in the measurement of cortisol. Our method has many advantages in that it requires a small volume of sample, has fast response time, is easy to operate and needs no labeling process. Besides, it will shed a light on the measurement techniques for emotion science.