• Journal of Microbiology and Biotechnology
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• v.17 no.8
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• pp.1403-1406
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• 2007

An antiproliferative agent, streptochlorin, was isolated from the fermentation broth of a marine actinomycete isolated from marine sediment. Phylogenetic analysis of the 16S rRNA gene sequence indicated that the strain belongs to the genus Streptomyces. Bioactivity guided fractionation of the culture extract by solvent partitioning, ODS open flash chromatography, and reversed-phase HPLC gave a pure compound, streptochlorin. Its structure was elucidated by extensive 2D NMR and mass spectral analyses. Streptochlorin exhibited significant antiproliferative activity against human cultured cell lines.

• Natural Product Sciences
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• v.13 no.3
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• pp.255-257
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• 2007

A simple reversed phase HPLC method was developed for extracting pharmacologically active compounds kurarinone and trifolirhizin from the roots of Sophora flavescens using a binary gradient of acetonitrile : $H_{2}O$ with UV detection at 254 nm. The kurarinone and trifolirhizin contents of the roots of S. flavescens collected from ten district markets in Korea and China were $77.24{\sim}686.89$ ${\mu}g/g$ and $46.89{\sim}288.58$ ${\mu}/g$, respectively.

• Archives of Pharmacal Research
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• v.27 no.4
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• pp.460-464
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• 2004

The quality of Alismatis Rhizoma was evaluated by reversed-phase high performance liquid chromatographic method. Alisol B 23-acetate was used as a standard marker for evaluation. This component was fully separated from the other components in the plant extracts on a ODS column. Identifcation of alisol B 23-acetate was carried out by comparing the LC/MS spectrum of separated peak from the extract with that of standard. Alisol B 23-acetate contents in Alismatis Rhizoma obtained from several herbal markets were varied from $0. 15\%$ to $0.56\%$.

• Archives of Pharmacal Research
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• v.26 no.7
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• pp.516-520
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• 2003

A reversed-phase high performance liquid chromatographic method was developed to determine the contents of psoralen and angelicin from some medicinal herbs. The optimum eluent for chromatography was 20 v/v% acetonitrile in water on a Zorbax 300SB $C_{18}$ column. The identification was carried out by comparing the retention time and mass spectra of the relevant peaks with their standards. The variation of the concentration of psoralen and angelicin was wide between different species. The seeds of Psoralea corylifolia showed the highest contents of psoralen (7.8 mg/g) and angelicin (2.3 mg/g) among the tested herbs.

• Journal of Photoscience
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• v.9 no.2
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• pp.367-369
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• 2002

Chlorophyll (ChI) a' is the Cl3$^2$-epimer of ChI a which is the constituent of P700, the primary electron donor of Photosystem (PS) I, of a thrmophilic cyanobacterium, Synechococcus elongatus, whose structure was recently determined by X-ray crystallography. To determine whether PS I of diverse oxygenic photosynthetic organisms universally contain one molecule of ChI a ’, pigment compositions of thylakoid membranes and PS I complexes isolated from cyanobacteria, green algae, red algae and higher plants were determined by reversed-phase HPLC. The results show that involvement of one ChI a'molecule in PS I is the universal feature for Chi a-based PS I of oxygenic photosynthetic organisms.

• 한국전산유체공학회:학술대회논문집
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• 2009.11a
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• pp.223-227
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• 2009

In the present study, a least square weighted residual method and Taylor-Galerkin method were formulated and tested for the discretization of the two hyperbolic type equations of level set method; advection and reinitialization equations. The two approaches were compared by solving a time reversed vortex flow and three-dimensional broken dam flow by employing a four-step splitting finite element method for the solution of the incompressible Navier-Stokes equations. From the numerical experiments, it was shown that the least square method is more accurate and conservative than Taylor-Galerkin method and both methods are approximately first order accurate when both advection and reinitialization phase are involved in the evolution of free surface.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.48
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• pp.72-78
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• 2003

Carotenoids are the major pigment of pepper (Capsicum annuum) and tomato (Lycopersicon esulentum) which are very important foods in Korea. However the analysis of carotenoids is quite complicated because of their diversity and the presence of cis-trans isomeric forms of these compounds. The objective of this review is to collect the achievements on the field of the chromatographic separation of carotenoids in food and some vegetables, to describe and critically evaluate the techniques, And to compare the benefits and shortcomings of the various chromatographic methods such as adsorption and reversed-phase HPLC and thin-layer chromatography. HPLC equipped with ultra-violet or photodiode array detection is most often employed in routine use for the analysis of carotenoids. Here, the method to analyze carotenoids by HPLC separation after solvent extration and purification from pepper powder samples done in our laboratory is also mentioned.

• Environmental Mutagens and Carcinogens
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• v.26 no.1
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• pp.25-29
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• 2006

Antimicrobial peptides (AMPs) play an important role in this response by rapidly killing invading microorganisms. In this study antimicrobial peptide has been isolated from acidified whole body extract of a bivalve mollusk, the marine mussel (Mytilus coruscus). This peptide purified to homogeneity by gel-filtration and reversed-phase high performance liquid chromatography. The molecular weight was 1464.92 Da, determined by MALDI-TOF Mass spectrometry. In addition to growth inhibition of Escherichia coli D31.

• Preventive Nutrition and Food Science
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• v.5 no.3
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• pp.148-152
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• 2000

Mussel adhesive protein (MAP) was extracted from Korean Mytilus edulis and then partially purified using Sephacryl S-300 gel permeation chromatography and reversed-phase high performance liquid chromatography. As an indicator of adhesiveness, is 3,4-dihydroxyphenylalanine (DOPA) content was determined. Its DOPA/protein ratio of 0.19 was higher than those of other reports, indicating a good adhesive. The partially purified MAP was confirmed by acid-urea polyacrylamide gel electrophoresis using cetylpiridinium bromide as a cationic detergent. Sea mussel hydrolysates were prepared using three commercial proteases to provide value-added functional materials and their angiotensin converting enzyme (ACE) inhibitory activities were determined. Among hydrolysates of sea mussel, Protamex was the best and further purification would improved ACE inhibitory activity.

• Preventive Nutrition and Food Science
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• v.12 no.3
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• pp.131-134
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• 2007

The kinetic analyses for thermal products of alpha-, gamma- and delta-tocopherols during heating as functions of temperature and time were studied. Alpha-, gamma- and delta-tocopherols dissolved in glycerol were heated at $100{\sim}200^{\circ}C$ for $5{\sim}60$ min. The thermal products were separated by hexane extraction and analyzed by HPLC using a reversed phase ${\mu}-Bondapak$ $C_{18}-column$ with two kinds of elution solvents in a gradient mode. The formation kinetics of thermal products of tocopherols followed a first-order kinetic model. The formation rate of thermal products of tocopherols was dependent on heating temperatures and heating times. The activation energy and enthalpy for the thermal products of ${\gamma}-and$ ${\delta}-tocopherols$ were higher than those for ${\alpha}-tocopherol$ as in the case of the oxidative degradation kinetics of tocopherol. The magnitude order of the activation energy was ${\gamma}->{\delta}->{\alpha}-tocopherol$.