• Preventive Nutrition and Food Science
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• v.9 no.4
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• pp.295-299
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• 2004

Alpha-tocopherol was thermally oxidized and degraded at high temperatures and the resulting products were chromatographically separated and identified by LC-MS. Alpha-tocopherol dissolved in glycerol was heated at 200^{\circ}C for 30 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: a mixture of acetonitrile and methanol (3:2), and of acetonitrile, methanol, 2-propanol, chloroform and methylene chloride (3:2:5:0.5:0.5) in a gradient mode. The isolated thermal. products of alpha-tocopherol were more viscous than alpha-tocopherol, and dark brown in color. Major thermal degradation products of alpha-tocopherol were identified by LC-MS, and the structures of thermal products were proposed. Alpha-tocopherol and its thermal degradation products were degraded into fragments, mainly at the non-aromatic parts. The degradation products of alpha-tocopherol. were combined with oxidized product (tocopherylquinone) to make thermal. products through dimerization.

• YAKHAK HOEJI
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• v.56 no.3
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• pp.145-151
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• 2012

To develop fundamental data of herbal materials with heat treatment, we studied analytical and extraction methods of benzopyrene in black ginseng and validated by HPLC analysis. Benzopyrene was successfully separated in mobile phase of acetonitrile:water (80 : 20) and detection of excitation 294 nm, emission 404 nm. The calibration curve of benzopyrene was linear over the concentration range of 1.17~37.50 ng/ml with correlation coefficient of above 0.999. The limit of detection (LOD) and quantitation (LOQ) of benzopyrene was 0.25 and 0.75 ng/ml, respectively. Hexane extraction method was used as a new extraction method for benzopyren and the efficient of extraction was over 95%. In conclusion, analytical method and extraction method were suitable for the determination of benzopyrene in the black ginseng and could be applied to fundamental study and guideline of herbal materials with heat treatment.

• Natural Product Sciences
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• v.19 no.3
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• pp.236-241
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• 2013

A high-performance liquid chromatography-diode array detector (HPLC-DAD) method was established for quantitative evaluation of nine constituents of Fraxinus rhynchophylla such as four coumarins, esculin (1), fraxin (2), esculetin (3), fraxetin (4), three lignans, syringaresinol 4,4'-O-${\beta}$-diglucoside (5), pinoresinol 4-O-${\beta}$-glucoside (6), pinoresinol (9), one secoiridoid, oleuropein (7), and one coumarinolignan, cleomiscosin C (8). The preferred chromatographic condition was obtained on Phenomenex Gemini-NX (3 ${\mu}m$, C18 110A, $150{\times}4.60$ mm) and the mobile phase was composed of water and acetonitrile using a gradient elution. The wavelength was set at 220 nm. Extraction condition of these constituents in F. rhynchophylla was also optimized through extraction time, extraction solvent and extraction method using established method. From this study, extraction at $70^{\circ}C$ with the mixture of ethanol and water for more than 12 h was suggested to be good extraction condition for these constituents. Quantitation of nine constituents in different F. rhynchophylla samples was also successfully accomplished with the newly established method.

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

• Analytical Science and Technology
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• v.6 no.5
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• pp.509-514
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• 1993

Benomyl, topsin-M and thiram been known as one of the seed disinfectant. For these studies benomyl, topsin-M and thiram simultaneously had been analyzed by high performance liquid chromatographic method using ODS cartridge, benomyl, topsin-M and thiram was chromatographed using an ODS column and eluent 40% Acetonitrile at a flow rate of 1ml/min. The UV Detector responses at 276nm.

• Journal of Korean Society on Water Environment
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• v.27 no.3
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• pp.329-333
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• 2011

p-phenylene-2,5-benzobisoxazole (PBO; Zylon$(R)$) fibers as an adsorbent were employed for solid phase extraction of aqueous alkylphenols. The removal ratios for 10 kinds of alkylphenols at initial concentration of $100{\mu}gL^{-1}$ were in the range of 16.8-96.3% and the removals increased with the increase of the phase ratio (fiber weight/solution volume). The plots of the logarithm of partition coefficient (log K) were correlated with the logarithm of the n-octanol/water partition coefficient (log P). The adsorbed alkylphenols were completely desorbed with the mixture of acetonitrile and dichloromethane.

• Proceedings of the Ginseng society Conference
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• 2002.10a
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• pp.491-501
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• 2002

A cross-examination between KT&G Central Research Institute and Guangzhou Institute for Drug Control was carried out in order to select optimum conditions for extraction, separation and determination of ginsenosides in red ginseng and to propose a better method for the quantitative analysis of ginsenosides. The optimum extraction conditions of ginsenosides from red ginseng were as follows: the extraction solvent, $70\%$ methanol; the extraction temperature, $100^{\circ}C;$ the extraction time, 1 hour for once; and the repetition of extraction, twice. The optimum separation conditions of ginsenosides on the SepPak $C_{18}$ cartridge were as follows: the loaded amount, 0.4 g of methanol extract; the washing solvents, distilled water of 25 ml at first and then $30\%$ methanol of 25 ml; the elution solvent, $90\%$ methanol of 5 ml. The optimum HPLC conditions for the determination of ginsenosides were as follows: column, Lichrosorb $NH_2(25{\times}0.4cm,$ 5${\mu}m$, Merck Co.); mobile phase, a mixture of acetonitrile/water/isopropanol (80/5/15) and acetonitrile/water/isopropanol (80/20/15) with gradient system; and the detector, ELSD. On the basis of the optimum conditions a method for the quantitative analysis of ginsenosides were proposed and another cross-examination was carried out for the validation of the selected analytical method conditions. The coefficient of variances (CVs) on the contents of ginsenoside-$Rg_{1}$, -Re and $-Rb_1$ were lower than $3\%$ and the recovery rates of ginsenosides were $89.4\~95.7\%,$ which suggests that the above extraction and separation conditions may be reproducible and reasonable. For the selected HPLC/ELSD conditions, the CVs on the detector responses of ginsenoside-Rg, -Re and $-Rb_1$) were also lower than $3\%$, the regression coefficients for the calibration curves of ginsenosides were higher than 0.99 and two adjacent ginsenoside peaks were well separated, which suggests that the above HPLC/ELSD conditions may be good enough for the determination of ginsenosides.

• Bulletin of the Korean Chemical Society
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• v.29 no.1
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• pp.94-98
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• 2008

A fundamental study was developed concerning the novel solvent extraction of the tetravalent metal ions; zirconium(IV), hafnium(IV) and thorium(IV). Their extraction behavior in toluene was investigated with a recently synthesized naphthol-derivative Schiff base, 1-({[4-(4-{[(E)-1-(2-hydroxy-1-naphthyl)methyliden]amino}phenoxy) phenyl]imino}methyl)-2-naphthol (HAPMN). The spectrophotometrical examination of the complex formation between HAPMN and the Zr(IV), Hf(IV) and Th(IV) ions in acetonitrile revealed the formation of stable 1:1 complexes in the solution. After the thorium extraction in toluene, it was found that [Th(OH)3HA] was the respective deriving substance. While, in the case of zirconium and hafnium extraction, the extracted adduct was found to be [M4(OH)8(H2O)16Cl62HA]. The stoichiometric coefficients of these extracted species were determined by the slope analysis method. The extraction reaction followed a cation exchange mechanism.

• Journal of Applied Biological Chemistry
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• v.64 no.3
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• pp.197-203
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• 2021

Saponarin is a crucial component of barley sprout, and the production and quantitative analysis are issued to date. In this study, the optimal saponarin extraction conditions were presented on the subject of acetonitrile, ethanol, methanol, and water for the quantitative analysis in barley sprout through the extraction efficiency compared with the solvent concentration and extraction time using the reaction surface methodology. The optimal extraction time and solvent condition for saponarin were 3.9 h and 53.7% of aqueous methanol, respectively. In addition, the effect of LED artificial light on the saponarin production in barley sprouts was evaluated by the light cycle, light quantity, and light quality. The optimal cultivation conditions under artificial light for the growth of barley sprout and saponarin production were most effectively achieved on 220-320 μmol m^-2 s^-1 of the light quantity with 8 h day^-1 of a daylight cycle under 6500K LED combined with red light. Furthermore, blue light was evaluated as the main factor in the biosynthesis of saponarin.

• Korean Journal of Veterinary Service
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• v.28 no.3
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• pp.285-294
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• 2005

This study was conducted to investigate the extraction method for the determination of organochlorine, organophosphorus and synthetic pyrethroid pesticide residues in beef fat by gas chromatography-mass selective detector(GC-MSD). Twenty one pesticide residues in fat were determined using a simple and rapid procedure based on solid- phase extraction(SPE) clean-up cartridges with octadecyl $(C_{18})-bonded$ porous silica, florisil, $10\%$ deactivated florisil. a tandem $C_{18}$ and florisil and a tandem $C_{18}$ and $10\%$ deactivated florisil. Solvent-solvent extraction using acetonitrile was not satisfied to eliminate fat interference for pesticide residue analysis by GC-MSD, and the recoveries of the method in fat ranged from 16.2 to $57.3\%$ except DDT$(83.2\%)$. The recoveries of SPE methods using a tandem $C_{18}$ and Florisil was $59.6\~123.8\%$ except fenitrothion $(135.2\%)$. the SPE method was verified the satisfactory performance of pre-treatment for pesticide residues analysis in fat by GC-MSD. The efficiency of florisil deactivated with $10\%$ water has been not proved significantly on recoveries of pesticide residues in fat.