• Journal of the Korean Applied Science and Technology
• /
• v.32 no.3
• /
• pp.461-468
• /
• 2015

Simultanious quantitative determination of Cetyltrimetyl ammonium chloride(CTM), Stearamidopropyl dimetylamine(SAP), Behentriammonium chloride(BHT), Dihexadeyldimethyl ammonium chloride(DHDDM) was carried out by reversed phase HPLC. The 0.2% TFA/Methanol was used for the mobile phase of gradient conditions. An Alltech $C_{18}$($250mm{\times}4.6mm$ i.d., $5{\mu}m$)and the selected ELSD detector was applied. The analysis results of HPLC showed good linearity with correlation coefficient of $r^2=0.997$ in the rage of $130{\sim}1980.5{\mu}g/mL$ and detection limit.

• Analytical Science and Technology
• /
• v.10 no.5
• /
• pp.343-349
• /
• 1997

Analytical method using the reversed phase ion-pair chromatography (RP-IPC) for the determination of kasugamycin(5-amino-2-methyl-6-(2,3,4,5,6-pentahydroxy cyclohexyloxy)tetrahydropyran-3-yl-amino-${\alpha}$-imino acetic acid), pesticide as fungicide bactercide has been established. The retention behavior of kasugamycin in the RP-IPC was examined with respect to the effect of concentrations of organic modifiers, pH of eluent and types and concentrations of the counter ions as ion-pair reagent. This method developed by the optimum factors, can be used for the application of the quality control in the crude product and its formulation.

• Journal of Pharmaceutical Investigation
• /
• v.35 no.1
• /
• pp.51-55
• /
• 2005

A high-performance liquid chromatographic method was employed for the determination of bumetanide in human plasma. After addition of internal standard (IS, naproxen) and acidification of the plasma with 1 M hydrochloric acid, the drug and IS were extracted into dichloromethane. The organic phase was back-extracted into 1 M sodium bicarbonate solution and 50 ${\mu}l$ of the aqueous phase was injected onto a reversed-phase C18 column with a mobile phase consisting of methanol: water: glacial acetic acid = 65 : 35 : 1. The samples were detected utilizing a fluorescence detector (excitation wavelength 235 nm, emission wavelength 405 nm). The method was specific and validated with a lower limit of 5 ng/mL. Intra- and inter-day precision and accuracy were acceptable for all quality control samples including the lower limit of quantification. The applicability of the method was demonstrated by analysis of plasma after oral administration of a single 2 mg dose to 24 healthy subjects. From the plasma bumetanide concentration vs. time curves, the mean AUC was $246.5{\pm}73.8\;ng{\cdot}hr/mL$ and $C_{max}$ of $132.1{\pm}40.9$ ng/mL reached 1.2 hr after administration. The mean biological half-life of burnet ani de was $1.1{\pm}0.2$hr. Based on the results, this simple and validated assay method could readily be used in any pharmacokinetic or bioequivalence studies using humans.

• Food Science of Animal Resources
• /
• v.30 no.6
• /
• pp.923-929
• /
• 2010

Colostral whey prepared from colostrum (pooled from first six post-partum milkings) was heated for 10 min at $100^{\circ}C$ Heated colostral whey was incubated with 1% enzymes (protein equivalent basis) for 15, 30, 60, 90, and 120 min at $50^{\circ}C$. Papain, pepsin, trypsin, and alcalase produced different degrees of hydrolysis (DH), 10.66%, 12.42%, 10.83%, and 25.31%, respectively, at an incubation time of 120 min. The SDS-PAGE reveals that significant amounts of bovine serum albumin (BSA), ${\beta}$-lactoglobulin (${\beta}$-LG), and ${\alpha}$-lactalbumin (${\alpha}$-LA) survived papain digestion. In contrast, pepsin completely removed BSA but not ${\beta}$-LG present in heated colostral whey. Alcalase completely eliminated BSA, ${\beta}$-LG, and ${\alpha}$-LA. This differential hydrolysis was confirmed by reversed-phase HPLC analysis. Using ion-exchange chromatography, fraction-1 (F-1) was obtained from alcalase hydrolysate at a NaCl gradient concentration of 0.25 M. Reversed-phase HPLC chromatograms of alcalase F-1 showed numerous small peaks, which probably indicate that a variety of new peptides were produced. Iron content of alcalase F-1 was 28.94 ppm, which was the highest among all enzyme fractions, whereas iron content of colostral whey was 36.56 ppm. Main amino acids contained in alcalase F-1 were Thr (15.45%), Glu (14.12%), and Ser (10.39%). Therefore, alcalase can be used to generate good iron-binding peptides in heated colostral whey, and the resulting iron-binding peptides could be suitable as a value-added food ingredient for food supplements.

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

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

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.51 no.spc1
• /
• pp.103-106
• /
• 2006

Anthocyanins are water-soluble glycosides and acylglycosides of anthocyanidins, having different color variations due to its substitution patterns. Anthocyanins, present in various fruits, vegetables and crops as natural colorant, have been well characterized for its bioactive properties, anti-oxidant, anti-cancer, anti-proliferative and anti-inflammatory properties. During extraction and purification, the factors, such as pH, temperature, oxygen, light, enzymes, nucleophilic agents, sugar derivatives and co-pigments, have affected on anthocyanin stability. For this reason, the extraction method should be thoroughly checked for the qualitative/quantitative analysis of anthocyanin in particular plant material. To identify the optimum extraction method of cyanidin-3-glucoside, major anthocyanin of dark purple-colored grains, Oryza sativa cv. Heugjinjubyeo, Phaselous vulgaris, Phynchosia gngularis, Sesamum indium, Rhynchosia nulubilis and Lablab purpureus, reversed-phase HPLC analysis using solvent system of acetonitrile, methanol and water were accomplished.

• Korean Journal of Pharmacognosy
• /
• v.41 no.1
• /
• pp.54-57
• /
• 2010

A reversed phase HPLC method was developed to determine the major components of Psoralea corylifolia, psoralen, isopsoralen, bakuchiol, and corylin. Quantitative analysis of the above compounds was performed by C-18 column using a gradient solvent system of acetonitrile and water with UV detection at 310 nm. The comparison of contents of psoralen, isopsoralen, bakuchiol, and corylin in psoraleae semen and the processed psoraleae semen was also investigated. In result, processed psoraleae semen showed more amounts of psoralen, isopsoralen, and corylin with 1.6, 4.3, and 1.3 mg/g, respectively, except bakuchiol (66.98 mg/g) while psoraleae semen showed 0.53, 1.56, 1.0, and 76.3 mg/g of psoralen, isopsoralen, corylin, and bakuchiol, respectively.

• Microbiology and Biotechnology Letters
• /
• v.22 no.1
• /
• pp.52-58
• /
• 1994

The induced antibiotic peptides were isolatde from the white-spotted folwer chafer, Protaetia brevitarsis by injection of E. coli suspension to the larvae of the insect. The antibacterial activity of the peptides were assayed by the plate growth ingibition method, and were purified by ion-exchange chromatography, reversed-phase HPLC, ion-exchange HPLC and SDS-PAGE etc. The peptides were estimated as 9 kDa in molecular weight and named Protaecin I and Protaecin II, respectively. Protaecin I and II have strong antibacterial activities against Gram-positivie and/or Gram-negative bacteria, and they are stable in the heat treatment and in the range of pH 2-12.

• Korean Journal of Pharmacognosy
• /
• v.24 no.1
• /
• pp.47-53
• /
• 1993

The seasonal variations of the major six flavonol glycosides(kaempferol 2,6-dirhamnosyl glucoside, quercetin 3-O-rutinoside, kaempferol 3-O-rutinoside, isorhamnetin 3-O-rutinoside, quercetin 3-O-coumaroyl glucorhamnoside and kaempferol 3-O-coumaroyl glucorhamnoside) in Ginkgo biloba leaves were investigated. The contents were determined by HPLC on reversed phase $C_{18}$ column. This result showed that the percentage of six flavonol glycosides decreased during the season from 1.57% in May to 0.39% in November. The content of each flavonol glycoside indicated a similar tendency to decrease. However, the contents of rutinosides of kaempferol, quercetin and isorhamnetin fluctuated markedly than those of coumaroyl glucorhamnosides of kaempferol and quercetin and kaempferol 2,6-dirhamnosyl glucoside.