• Analytical Science and Technology
• /
• v.30 no.2
• /
• pp.102-111
• /
• 2017

Here we reported a methodology for identification of triacylglycerols (TAGs) and diacylglycerols (DAGs) in coix seed by preparative thin layer chromatography (prep-TLC) and non-aqueous reversed-phase liquid chromatography (NARP LC)-atmospheric pressure chemical ionization (APCI) tandem mass spectrometry (MS/MS). Lipid components were extracted from coix seed by reflux extraction using n-hexane for 3 hr. TAGs and DAGs in coix seed extract were effectively purified and isolated from matrix interferences by prep-TLC and then analyzed by LC-APCI-MS and MS/MS for identification. TAGs were effectively identified taking into consideration of their LC retention behavior, APCI-MS spectra patterns, and MS/MS spectra of $[DAG]^+$ ions. In MS/MS spectra of TAGs, diacylglycerol-like fragment $[DAG]^+$ ions were useful to identify TAGs with isobaric fragment ions. Based on an established method, 27 TAGs and 8 DAGs were identified in coix seed extract. Among them, 15 TAGs and 8 DAGs were for the first time observed in coix seed. Interestingly, some of TAGs isolated by prep-TLC were partly converted into DAGs through probably photolysis process during storing in room temperature. Thus, degradation phenomenon of TAGs should be considered in the quality evaluation and nutritional property of coix seed. LC-APCI-MS/MS combined with prep-TLC will be practical method for precise TAG and DAG analysis of other herbal plants.

• Textile Coloration and Finishing
• /
• v.14 no.4
• /
• pp.240-248
• /
• 2002

The most effective solvent for extract of dye from amur cork tree was methanol. Two protoberberine alkaloids, berberine and palmatine, were isolated from amur cork tree by Prep-TLC, and the developing solvent was Benzene : AcOEt ; PrOH ; MeOH ; EtNH$_2$(8: 4: 2: 0.5: 0.5). Dyes were stable at a high temperature and there wasn't any change of color at pH 3~9 and with added metal mordants. In adsorption spectra of aqueous solution of berberine and tannin mixture, two isosbestic points$(328^{nm},\;357^{nm})$ were found and the mole fraction of reaction of components was 1:1.

• Proceedings of the Korean Society of Near Infrared Spectroscopy Conference
• /
• 2001.06a
• /
• pp.3114-3114
• /
• 2001

During the last years phytochemistry and phytopharmaceutical applications have developed rapidly and so there exists a high demand for faster and more efficient analysis techniques. Therefore we have established a near infrared transflectance spectroscopy (NIRS) method that allows a qualitative and quantitative determination of new polyphenolic pharmacological active leading compounds within a few seconds. As the NIR spectrometer has to be calibrated the compound of interest has at first to be characterized by using one or other a combination of chromatographic or electrophoretic separation techniques such as thin layer chromatography (TLC), high performance liquid chromatography (HPLC), capillary electrophoresis (CE), gas chromatography (GC) and capillary electrochromatography (CEC). Both structural elucidation and quantitative analysis of the phenolic compound is possible by direct coupling of the mentioned separation methods with a mass spectrometer (GC-MS, LC-MS/MS, CE-MS, CEC-MS) and a NMR spectrometer (LC-NMR). Furthermore the compound has to be isolated (NPLC, MPLC, prep. TLC, prep. HPLC) and its structure elucidated by spectroscopic techniques (UV, IR, HR-MS, NMR) and chemical synthesis. After that HPLC can be used to provide the reference data for the calibration step of the near infrared spectrometer. The NIRS calibration step is time consuming, which is compensated by short analysis times. After validation of the established NIRS method it is possible to determine the polyphenolic compound within seconds which allows to raise the efficiency in quality control and to reduce costs especially in the phytopharmaceutical industry.

• Journal of Ginseng Research
• /
• v.22 no.4
• /
• pp.284-288
• /
• 1998

This study was carried out to establish a new efficient method for isolation and purification of ginsenosides. Silica gel column chromatography, having been used for the isolation of ginsenosides, is advantageous to obtain a large amount of ginsenosides. However, it has a disadvantage to isolate ginsenosides to their highest purity. In addition, normal-or reverse-phase HPLC method thus far reported is confined to quantitative analysis. Especially, it has not been possible to isolate racemic 20(S)- and 20(R)-ginsenoside Rg2. In this experiment, isolation and purification of ginsenosides were accomplished by Diaion HP-20 adsorption chromatography, silica gel column chromatography, recrystalization and Prep. HPLC with or without Prep. TLC. From this study, we could establish a new efficient method for isolation and purification of 9 major and/or minor ginsenosides.

• Journal of the Korean Wood Science and Technology
• /
• v.49 no.1
• /
• pp.23-43
• /
• 2021

In this study, we selected two essential oils, Citrus unshiu and Cinnamomum cassia with superior antioxidant effects from the essential oils of 7 wild plants in South Korea and examined their antimicrobial activity against Candida albicans, which causes dermatitis to identify the antimicrobial components in the essential oils. As a result of measuring DPPH (1,1-diphenyl-2-picrylhydrazyl) radical scavenging activity, SC50 value of the Citrus unshiu essential oil was 0.010 mg/mL, while for the Cinnamomum cassia essential oil, SC50 value was 0.09 mg/mL. In addition, when ABTS (2,2'-azinobis (3-ethylbenzothiazoline-6-sulfonic acid) radical scavenging activity was measured, SC50 value of the Citrus unshiu essential oil was 0.09 mg/mL, while for the Cinnamomum cassia essential oil, it was 0.06 mg/mL, exhibiting high antioxidant activity. For the minimum inhibitory concentration (MIC), the essential oil of Cinnamomum cassia was 1.25 mg/mL and that of Citrus unshiu was 5 mg/mL, demonstrating a high antimicrobial activity of the Cinnamomum cassia essential oil. Through the thin layer chromatography (TLC) bioassay, we assessed the antimicrobial activity against C. albicans according to the fraction components of the two essential oils. Also, by using preparative TLC (prep. TLC), we obtained the active fractions, and by performing GC/MS analysis of the components with the same Rf value, we identified the antimicrobial-active components. As a result, the main components having antioxidant and antimicrobial activities were cinnamyl acetate, eucalyptol, linalool, and citral of the Cinnamomum cassia essential oil and linalool from the Citrus unshiu essential oil. Also, based on the analysis of the fractional components that showed antioxidant and antimicrobial activities in both of the two essential oils, it was found that linalool has antioxidant activity, while cinnamyl acetate, eucalyptol, citral, and geranyl acetate have antioxidant and antimicrobial activities.

• Korean Journal of Food Science and Technology
• /
• v.19 no.5
• /
• pp.392-396
• /
• 1987

A method for isolation of some phenolic acids from Korean ginseng(Panax ginseng C.A.Meyer)was studied using silicic acid column chromatography. preparative thin layer chromatography and high performance liquid chromatography. Two phenolic compounds were isolated and identified as ferulic acid, mp $156-157^{\circ}C$ and vanillic acid. mp $154-156^{\circ}C$ by spectral data of Mass and NMR spectroscopy.

• Journal of the Korean Wood Science and Technology
• /
• v.32 no.2
• /
• pp.33-39
• /
• 2004

Four phenolic compounds were isolated from the wood and bark of Magnolia sieboldii. The structures were determined as : costunolide (I), syringin (II), 1, 2-dihydroxyxanthone (III), and vanillic acid (IV), respectively, on the basis of spectroscopic data.

• Analytical Science and Technology
• /
• v.7 no.4
• /
• pp.547-554
• /
• 1994

Ceramide components were detected from a native mushroom, "Phellinus ribis" growing in Korea. Cerebroside fractions were isolated by silica column chromatography. The ceramide fraction were purified by preparative TLC and their constituents were analyzed by using GC-MS and FAB-MS. The fatty acid components consisted of mainly hydroxy fatty acids($C_{22:0}$, $C_{25:0}$, $C_{24:0}$, $C_{23:0}$) : The major components of long-chain base were trihydroxy-bases, principally 4-hydroxy sphinganin analogues.

• Journal of Life Science
• /
• v.18 no.2
• /
• pp.206-212
• /
• 2008

The quorum sensing (QS) regulatory network has been the subject of extensive studies during recent years and has also attracted a lot of attention because it both positively and negatively regulates various putative virulence factors, although initially considered to be a specialized system of Vibrio fischeri and related species. In this study, to identify the novel materials which inhibit QS system of microorganisms, extracts of eighteen natural products were tested by bioassay using N-(3-oxohexanoyl)-$_L$-homoserine lactone and N-(3-oxooctanoyl)-$_L$-homoserine lactone synthesized in this experiment and an Agrobacterium tumefaciens NT1 biosensor strain containing a traI::lacZ fusion. The result indicated that the extracts of cabbage, leek, and onion exhibited the QS inhibition activity. Thus, materials contained in the extracts were isolated via recycling preparative HPLC and were purified via a JAIGEL-LS255 column. The common fraction corresponding to a peak of the 83 min point of them quenched the quorum sensing of A. tumefaciens NT1 biosensor strain in ABMM containing X-gal and was designated quorum sensing inhibitor-83 min (QSI-83). The QSI-83 exhibited the heat stability and did not inhibit the growth of A. tumefaciens NTl. Furthermore, thin layer chromatography (TLC) results suggested that these novel materials may be antagonists of N-acyl homoserine lactone or may inhibit the QS autoinducer synthesis by Pseudomonas syringae pv. tabaci.

• Korean Journal of Organic Agriculture
• /
• v.29 no.1
• /
• pp.97-109
• /
• 2021

Plant parasitic nematodes are causing significant damage in crop production. There is a need to develop eco-friendly nematicide that reduces the damage of nematode and has little effect on the environment and human. In this study, we have isolated a substance having nematicidal activity from Ginkgo biloba L. outer seedcoat. Studies of G. biloba L. outer seedcoat are insufficient compared to the seed and leaves due to their odor and toxicity. The dried G. biloba L. outer seedcoat was extracted with dichloromethane:methanol (1:1) and fractionated into hexane, ethyl acetate and H₂O. Four steps TLC were performed from EtOAc fraction to purely isolate GB4-3 with nematicidal activity. To compare nematicidal activity, G. biloba L. seedcoat methanol extract and purified GB4-3 were investigated in terms of treatment concentration and time. As a result, the nematicidal activity increased with concentration and time. In the place treated with 20 ㎍/mL of crude G. biloba L. seedcoat MeOH extract, strong activity appeared after 12 hours, and 46% nematicidal activity shown after 18 hours. About 69% of nematicidal activity was confirmed in the place where GB4-3 purified from outer seedcoat was treated with 20 ㎍/mL, and the possibility of development as nematicide was very high. This study could be used as a basic data for the development of a nematode preparation from G. biloba L. outer seedcoat.