• Applied Chemistry for Engineering
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• v.8 no.2
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• pp.286-291
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• 1997

Taxol which is recognized as a powerful anticancer reagent was extracted from yew extract and separated by NP-HPLC (Normal-PhaseHigh Performance Liquid Chromatography). The experiments were performed in the isocratic mode with $5{\mu}l$ to $100{\mu}l$ injection volume and 1ml/min mobile phase flow rate. The major mobile phase was hexane and small amounts of ethanol, methanol, 1-propanol and isopropanol were added to change the retention behavior. Prior to a real sample, the artificial mixture of taxol, cephalomannine and 10-deacetyltaxol was tested. They are hard to be separated because of similar chemical structures. The experimental results showed that the proper composition of mobile phase for separating the three components was found 96% hexane and 4% ethanol(vol.%) or 96% hexane, 2% 1-propanol and 2% methanol(vol.%). Compared to the run time of 80 minutes for the binary system, the mixture was separated within 50 minutes with the less amount of mobile phase for the ternary system. Finally, $1{\mu}g$ of taxol was separated from yew tree extracts under the optimum operating conditions.

• 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.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.24 no.3
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• pp.111-115
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• 1998

We investigated the stability of all-trans-retinol on the liquid crystalline O/W emulsion composed of mainly alkyl polyglycerine, alkyl polyglucose and glycerine, and compared the activity of all-trans-retinol in the various forms of liquid crystal. Under certain conditions, novel liquid crystalline gel was formed around oil droplets, and layers of this liquid crystalline gel were very wide and rigid. (SWLC; Super Wide Liquid Crystal) SWLC was very helpful to stabilize retinol in O/W emulsion. After storage at 45 C for 4 weeks, all-trans-retinol in O/W emulsion composed of SWLC retained above 85% of the activity upon HPLC analysis, whereas those within no liquid crystalline emulsion gave 47% and normal liquid crystalline emulsion composed of fatty alcohols gave 40 60%. Retinol in oil phase is nealy insoluble in pure water, but in cosmetic emulsion systems can be slightly solubilized into water because emulsifiers and polyols in emulsion systems function as solubilizers. In this case, water in outer phase acts as a media for oxygen transporation$.$and thus destabilizes retinol. As a result, retinol in O/W emulsion has a tendency to become unstable. SWLC surrounding oil droplet which contains retinol is wide and rigid, therefore reduces contact between inner phase and outer phase To make SWLC, properties of emulsifiers are very important phase transition temperature should be high, and the structure of surfactants should be bulky, and their ratio should be suitable to make rigid and wide liquid crystalline gel layer in order to reduce contact between retinol in inner phase and water in outer phase.

• Analytical Science and Technology
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• v.20 no.5
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• pp.424-433
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• 2007

An analytical method for the determination of thyroid hormones in plasma samples has been studied by solid-phase extraction and high-performance liquid chromatography/diode array detector (DAD)/electrospray ionization (ESI)-mass spectrometer. Seven thyroid hormones were successfully separated by gradient elution on the reverse phase Hypersil ODS column (4.6 mm I.D., 250 mm length, particle size $5{\mu}m$) with ammonium formate buffer and acetonitrile. In addition, these compounds were confirmed by UV spectra and ESI-mass Spectra. The extraction recoveries of thyroid hormones in the plasma sample (at pH 3) were in the range of 74.5-115.7 % with solid-phase extraction by C18, followed by elution with 4 mL of methanol. The calibration curves showed good linearity with the correlation coefficients ($r^2$) varying from 0.9939 to 0.9978 and the detection limits of all analytes were obtained in the range of 20-50 ng/mL (38.1-162.8 pmol/mL). As a result, thyroxine was found in the range of 50.98-112.97 ng/mL in normal plasma samples.

• Food Science and Preservation
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• v.17 no.6
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• pp.903-907
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• 2010

We isolated a calcium-binding substance from Smilacis rhizoma hot-water extract using ion exchange, normal phase HPLC, and gel filtration chromatography; fractions were analyzed for calcium-binding activity. Fractions (F6) with the highest calcium-binding activity from the resource Q coulmn were pooled and further purified on an $NH_2$ column. Two major peaks were separated and the fraction (F61) with the higher calcium-binding activity was then loaded onto a $Superdex^{TM}$ column. A single peak (F611) with calcium-binding activity was finally obtained. These results suggest that the isolated calcium-binding fraction could be used as a functional food additive, similar to a calcium supplement, in the food industry.

• Journal of the Korean Applied Science and Technology
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• v.10 no.2
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• pp.11-18
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• 1993

Contents of vitamin $D_3$ and 25-OH-vitamin $D_3$ in marine animal products(20 species) were determined by HPLC. The isomers of vitamin D, $D_2$ and $D_3$, were not clearly separated on a reversed phase, ${\mu}$ Bonda Pak, with 20% methanol-acetonitrile, and on a normal phase, Zorbax SIL. with 0.4% isopropanol-hexane, but 25-OH-vitamin $D_2$ and-$D_3$ were separated on either ${\mu}$ Bonda Pak with 10% methanol-acetonitrile, or on Zorbax SIL with 2.2% isopropanol-hexane, respectively. Although levels of vitamin $D_3$ and 25-OH-vitamin $D_3$ varied remarkably according to species, their average value(fish : $l,l87{sim}36,007$ I.U/sample 100g, mussel : $58{\sim}1,706$ I.U/sample 100g, pickle: $1,208{\sim}79,358$ I.U/sample 100g) was greatly higher than that of meat($80{\sim}100$ I.U/sample 100g) and dairy products($400{\sim}800$ I.U/sample 100g). Fatty tissues of fish and pickled fish intestines contained high level of vitamin $D_3$ and 25-OH-vitamin $D_3$, while the clam and mussel known to have various kinds of sterol including ${\Delta}^7$-sterol showed very low levels of vitamin $D_3$ and its derivative.

• Food Science and Preservation
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• v.19 no.3
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• pp.438-442
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• 2012

To prepare calcium-binding peptides as calcium supplement, barley proteins were hydrolyzed using Flavourzyme for 18 h and the hydrolysates were ultra-filtered under 3 kDa as a molecular weight. The resultant filtered peptides were fractionated using ion exchange and normal-phase high performance liquid chromatography. Then each fraction that was obtained was determined for its calcium-binding activity to isolate the calcium-binding peptides. As a result, the highest calcium-binding peptide fraction was obtained, and the results suggest that barley protein hydrolysates can be used as a calcium supplement.

• Bulletin of the Korean Chemical Society
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• v.34 no.9
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• pp.2623-2628
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• 2013

Three di-acyl chlolide reagents, adipoyl chloride, terephthaloyl chloride and isophthaloyl chloride, were used as spacer reagents to prepare bonded type of three cellulose (3,5-dimethylphenyl)carbamate (CDMPC) chiral stationary phases (CSPs). The CDMPC CSPs were prepared using these three acid chlorides as spacer agents at the 6-position of the primary hydroxyl group on the glucose unit of cellulose regioselectively. The chiral recognition ability of the prepared CSPs for five racemates was evaluated by normal-phase high-performance liquid chromatography (HPLC) with the following mobile phases: hexane/isopropanol (IPA), hexane/IPA/tetrahydrofuran (THF) and hexane/IPA/chloroform. The result showed that these prepared CSPs can be used in THF and chloroform solutions and the chiral recognition abilities of the CSPs were improved depending on the eluents and chiral samples.

• Journal of Microbiology and Biotechnology
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• v.11 no.2
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• pp.204-210
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• 2001

Paclitaxel can be produced in high yield and with a high degree of purify from plant cell cultures of Taxus chinensis. The complete purification method was systematically established and described. This method was an efficient procedure for the purification of paclitaxel from crude paclitaxel, consisting or reverse-phase chromatography, followed by a normal-phase chromatography. The two-stage HPLC purification scheme serves as an effective and economical approach for resolving paclitaxel from complex mixtures of taxoids, with high purify (>99%) and low impurities (<0.1%). The process is readily scalable to a pilot plant and eventually to a production environment where multikilogram quantities of material are expected to be produced. The process has been optimized to minimize solvent usage, complexity, and operating costs.

• Applied Chemistry for Engineering
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• v.8 no.4
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• pp.694-699
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• 1997

Normal-phase HPLC was used to separate the useful phospholipids, PE, PI and PC in soybean lecithin. The mobile phase used in this experiments were haxane, isopropanol and methanol, the gradient mode was applied as the three components could not be separated by the isocratic mode. To find the optimum separation condition, the concentration profiles of effluents were calculated from the plate theory and the capacity factor in step-gradient mode. From the calculated results, PE was separated with hexane/isopropanol/methanol = 90/5/5vol.% in isocratic mode and PI and PC were resolved in the conditions of 10min gradient time and the second mobile phase of hexane/isopropanol/methanol=50/20/30vol.% in step-gradient mode. The agreement between the calculated concentration profile and experimental data was good, so the methodology developed in this work can be used to obtain the optimum separation condition in gradient mode.