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Journal articles on the topic 'Preparative layer chromatography'

Author: Grafiati

Published: 4 June 2021

Last updated: 26 January 2023

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1

Nyiredy, Szabolcs. "The Role of Planar Chromatography in Medicinal Plant Research." Journal of AOAC INTERNATIONAL 84, no. 4 (2001): 1219–31. http://dx.doi.org/10.1093/jaoac/84.4.1219.

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Abstract This paper summarizes the role of planar chromatography (PC) in medicinal and aromatic plant (MAP) research and development, and demonstrates the importance of the technique, after extraction, in the analysis of MAP (identification and quantitative determination of the separated compound/s), in the purification and isolation process, and in different types of screening procedure. Special attention is paid to analytical, micropreparative and preparative forced-flow techniques, for example overpressured-layer chromatography (OPLC) and rotation planar chromatography (RPC). The special features of analytical, micropreparative, and preparative layer chromatography (PLC), OPLC, and RPC are compared in tables. Purification and isolation procedures using forced-flow techniques are shown in flowcharts. Some applications, relating to different classes of substance, are presented to demonstrate the versatility of various planar chromatographic techniques.

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2

Stránský, Karel, Marta Semerdžieva, Miroslav Otmar, et al. "Antifungal Antibiotic from the Mushroom Agrocybe aegerita (BRIG.) SING." Collection of Czechoslovak Chemical Communications 57, no. 3 (1992): 590–603. http://dx.doi.org/10.1135/cccc19920590.

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An extract from a submersed culture of the mushroom Agrocybe aegerita (BRIG.) SING., containing antifungal antibiotic compounds was chromatographed on a silica gel column. Compounds from fractions which displayed the highest biological activity were concentrated and isolated by means of preparative thin-layer chromatography and preparative high-performance liquid chromatography, and were further characterized by means of gas chromatography, mass spectrometry and nuclear magnetic resonance. They are sesquiterpenic diols predominantly with an illudine skeleton. Structural formulae are proposed for some of them.

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3

Sherma, Joseph. "Biennial Review of Planar Chromatography: 2013–2015." Journal of AOAC INTERNATIONAL 99, no. 2 (2016): 323–31. http://dx.doi.org/10.5740/jaoacint.15-0284.

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Abstract The most important advances in planar chromatography published between November 1, 2013 and November 1, 2015 are reviewed in this paper. Included are an introduction to the current status of the field; student experiments, books, and reviews; apparatus and techniques for sample preparation and TLC separations; detection and identification of separated zones; quantitative analysis; preparative layer chromatography; and thin layer radiochromatography. Selected applications are given in the various sections of the review.

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4

Sherma, Joseph. "Biennial Review of Planar Chromatography: 2015–2017." Journal of AOAC INTERNATIONAL 101, no. 4 (2018): 905–13. http://dx.doi.org/10.5740/jaoacint.17-0454.

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Abstract The most important advances in planar chromatography published between November 1, 2015, and November 1, 2017, are reviewed in this paper. Included are an introduction to the current status of the field; student experiments and reviews; apparatus and techniques for sample preparation and TLC separations; detection and identification of separated zones; quantitative analysis; preparative layer chromatography; and thin-layer radiochromatography. Selected applications are given in the various sections of the review.

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5

Ajeel, Zaineb H., and Maha N. Hamad. "Detection and isolation of flavonoid and aromatic acid from Cynara scolymus different parts cultivated in iraq." Iraqi Journal of Pharmaceutical Sciences ( P-ISSN 1683 - 3597 E-ISSN 2521 - 3512) 29, no. 2 (2020): 202–13. http://dx.doi.org/10.31351/vol29iss2pp202-213.

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The target of this study was to study the natural phytochemical components of the head (capsule) of Cynara scolymus cultivated in Iraq. The head (capsule) of plant was extracted by maceration in70% ethanol for 72 hours, and fractioned by hexane, chloroform and ethyl acetate. Preliminary qualitative phytochemical screening was performed on the ethyl acetate fraction for capsule was revealed the presence of flavonoid and aromatic acids. These were examined by (high -performance liquid chromatography) (HPLC diodarray), (high- performance thin-layer chromatography)(HPTLC). Flavonoids were isolated by preparative layer chromatography and aromatic acid was isolated by preparative high-performance liquid chromatography HPLC from the ethyl acetate fraction of capsule. Then identified by High Performance Thin Layer Chromatography HPTLC, High performance liquid chromatography HPLC diode array , ultraviolet diode array UV-diode array and Liquid Chromatography /Mass Spectroscopy LC/MS. The chloroform fraction from the capsule was evaluated by Gas Chromatography//Mass Spectrometer(GC/MS). The different chromatographic and spectroscopic techniques revealed the presence of luteolin, apigenin and cinnamic acid in capsule of Cynara scolymus, also 9-octadecanoic acid (oleic acid), Oxalic acid, allyl tetradecyl ester, limonene, in chloroform of Cynara scolymus. The results of the current study proved the presence of luleolin, apigenin, and cinnamic acid in the ethyl acetate fraction of Cynara scolymus capsule.

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6

Schwack, Wolfgang. "Teresa Kowalska, Joseph Sherma (Eds.): Preparative Layer Chromatography." Analytical and Bioanalytical Chemistry 388, no. 5-6 (2007): 999–1000. http://dx.doi.org/10.1007/s00216-007-1328-6.

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7

Botz, L., Sz Nyiredy, and O. Sticher. "New Efficient Isolation Methods Using Preparative Layer Chromatography." Planta Medica 56, no. 06 (1990): 594. http://dx.doi.org/10.1055/s-2006-961204.

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8

Sherma, Joseph. "Biennial Review of Planar Chromatography: 2009–2011." Journal of AOAC INTERNATIONAL 95, no. 4 (2012): 992–1009. http://dx.doi.org/10.5740/jaoacint.sherma_review.

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Abstract The most important advances in the planar chromatography published between November 1, 2009 and November 1, 2011 are reviewed in this paper. Included are an introduction to the current status of the field; history, student experiments, books, and reviews; theory and fundamental studies; apparatus and techniques for sample preparation and TLC separations (sample application and plate development with the mobile phase); detection and identification of separated zones (chemical and biological detection, TLC/MS, and TLC coupled with other methods); techniques and instruments for quantitative analysis; preparative layer chromatography; and thin layer radiochromatography. Selected applications are given in the various sections of the review, especially for modern HPTLC-densitometry.

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9

Sherma, Joseph. "Biennial review of planar chromatography: 2011–2013." Open Chemistry 12, no. 4 (2014): 427–52. http://dx.doi.org/10.2478/s11532-013-0402-5.

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AbstractThe most important advances in planar chromatography published between November 1, 2011 and November 1, 2013 are reviewed in this paper. Included are an introduction to the current status of the field; student experiments, books, and reviews; theory and fundamental studies; apparatus and techniques for sample preparation and TLC separations (sample application and plate development with the mobile phase); detection and identification of separated zones (chemical and biological detection, TLC/mass spectrometry, and TLC coupled with other spectrometric methods); techniques and instruments for quantitative analysis; preparative layer chromatography; and thin layer radiochromatography. Numerous applications to a great number of compound types and sample matrices are presented in all sections of the review.

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10

Muhammad, Ilias, Volodymyr Samoylenko, Francis Machumi, et al. "Preparation and Application of Reversed Phase ChromatorotorTM for the Isolation of Natural Products by Centrifugal Preparative Chromatography." Natural Product Communications 8, no. 3 (2013): 1934578X1300800. http://dx.doi.org/10.1177/1934578x1300800308.

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A method of preparation of rotors with a reversed phase (RP) solid silica gel sorbent layer has been developed for centrifugal preparative chromatography (CPC), also known as rotational planar chromatography (RPC). The rotors consist of binder free RP solid SiO2 layers of different thicknesses packed between two supported circular glass discs and can be used in any appropriate device for centrifugal chromatography, like Chromatotron® and CycloGraph®. Polar and /or semi-polar compounds with close R f values, as well as extracts and column fractions were separated and /or purified in a preparative and / or semi-preparative scale using the RP rotors, eluted with mixtures of aqueous-based solvents. We herein report three examples of its application, using RP ChromatorotorsTM, for the isolation of the diastereoisomeric alkaloids banistenosides I and II from Banisteriopsis caapi, saponins III and IV from Fagonia cretica, and the sesquiterpenes artemisinin (V) and artemisinic acid (VI) from Artemisia annua.

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11

Kim, Yong J. "A Simple Streaking Device For Preparative Thin Layer Chromatography." Journal of Chemical Education 75, no. 5 (1998): 640. http://dx.doi.org/10.1021/ed075p640.1.

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12

Mincsovics, Emil, Márta Garami, László Kecskés, et al. "Personal Overpressured-Layer Chromatography (OPLC) Basic System 50, Flexible Tool in Analytical and Semipreparative Work." Journal of AOAC INTERNATIONAL 82, no. 3 (1999): 587–98. http://dx.doi.org/10.1093/jaoac/82.3.587.

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Abstract A new automated overpressured-layer chromatographic (OPLC) system called the Personal OPLC Basic System 50 is suitable for analytical and semi preparative separations. The automatic microprocessor-controlled system ensures rapid and reproducible off-line isocratic and stepwise gradientseparations. High external pressure (5 MPa) makes the sorbent layer more homogeneous, yielding more efficient off-line separation compared with those by early Chrompres chambers. A theoretical plate height of 10–30 μm can be achieved on an analytical high-performance thin-layer chromatographic (HPTLC) layer made of irregular silica gel with an average particle size of 5 μm if an optimal linear velocity (20–40 mm/min) and a nonviscous solvent system are used. On an analytical layer of 3 μm spherical silica gel, a theoretical plate height of 6–15 μm can be reached. Rapid analytical separations of resveratrol (1555 s) and xanthine by one-(498s) and two-directional (274 s) off-line developments were accomplished. On-line separation and detection combined with off-line sample application and fully on-line processing (including on-line sample application, separation, and detection) were fulfilled with a TLC plate for xanthine separation. Semi preparative isolation of xanthines was achieved through a fully on-line OPLC operating mode and scaled-up chromatography.

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13

Ghalib, Suroor A., and Enass J. Kadhim. "The Investigation of Some Phytochemical Compounds Found in Anchusa strigosa L. Grown Naturally in Iraq." Iraqi Journal of Pharmaceutical Sciences ( P-ISSN: 1683 - 3597 , E-ISSN : 2521 - 3512) 30, no. 1 (2021): 179–88. http://dx.doi.org/10.31351/vol30iss1pp179-188.

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Anchusa strigosa L.: Hardy annual biennial or perennial herb, with hairs especially on the leaves., flowers generally regular. Commonly named (Lisan Althour) in Iraq, from Boraginaceae family. The plant contains phenolic acids, flavonoids, alkaloids, sterols, and terpenoids. The Whole plant part defatted with n-hexane for 24 hours. The defatted plant material extracted using absolute methanol by Soxhlet apparatus for 24 hours, the extract fractionated by solvents of different polarity: petroleum ether- chloroform - ethylacetate- and n-butanol respectively. The n-butanol fraction hydrolyzed with 10% HCl for 5 hours by reflex to break down the glycosidic linkage. Rosmarinic acid, caffeic acid, genistein, and silybin were isolated from ethyl acetate fraction by preparative layer chromatography which identified by high performance liquid chromatography HPLC, Fourier transforms infrared (FTIR) spectra, thin- layer chromatography TLC and melting point. Since the plant contain alkaloids so acid- base extraction performed for crude extract resulting from the maceration of the plant parts in methanol (cold method) to obtain the alkaloid that isolated by preparative layer chromatography and then identified by Fourier transforms infrared (FTIR) spectra and thin-layer chromatography (TLC). The aim of this research was to carry out a phytochemical study of this plant since no previous phytochemical investigation work had been done on this species in Iraq.

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14

Mejbaum-Katzenellenbogen, W., F. Tłuścik, A. Kozubek, and A. Sikorski. "Alkylresorcinols in rye (Secale cereale L.) grains. I. Micromethod for determination of alkyl derivatives of resorcinol in rye grain." Acta Societatis Botanicorum Poloniae 44, no. 4 (2015): 479–89. http://dx.doi.org/10.5586/asbp.1975.044.

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A pure preparation of alkylresorcinol from rye grains was obtained by preparative thin-layer chromatography, which gave a UV spectrum characteristic for 5-n-alkylresorcinols and orcinol. This preparation served as standard in the elaboration of a micro method (for alkylresorcinols determination in acetone extract from rye grain. It was found that this method is suitable for selective determination of 5-n-alkylrezorcinols in acetone extracts from rye grains.

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15

SUGIYAMA, TAKEYOSHI. "Rapid development methods of preparative large thin-layer chromatography (TLC)." Kagaku To Seibutsu 28, no. 1 (1990): 59–61. http://dx.doi.org/10.1271/kagakutoseibutsu1962.28.59.

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16

Moschidis, Michael C. "Notizen: Isolation of Beef Brain Phosphonolipids by Thin Layer Chromatography: Their Identification and Silicic Acid Column Chromatographic Separation." Zeitschrift für Naturforschung C 41, no. 3 (1986): 369–74. http://dx.doi.org/10.1515/znc-1986-0323.

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The isolation and identification of the phosphonolipids from beef brain - right lobe, left lobe and cerebellum - is herein reported. The phosphonolipids were isolated by preparative thin layer chromatography (TLC) using the solvent system methanol/water (2:1, v/v) and identified preliminarily by TLC. The isolated phosphonolipids were subjected to silicic acid column chromatographic separation and the thus separated phosphonolipids were identified by TLC, nitrogen-phosphorus determinations and IR spectroscopy.

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17

Móricz, Ágnes M., Péter G. Ott, Ágnes Alberti, et al. "Applicability of Preparative Overpressured Layer Chromatography and Direct Bioautography in Search of Antibacterial Chamomile Compounds." Journal of AOAC INTERNATIONAL 96, no. 6 (2013): 1214–21. http://dx.doi.org/10.5740/jaoacint.sgemoricz.

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Abstract In situ sample preparation and preparative overpressured layer chromatography (OPLC) fractionation on a 0.5 mm thick adsorbent layer of chamomile flower methanol extract prepurified by conventional gravitation accelerated column chromatography were applied in searching for bioactive components. Sample cleanup in situ on the adsorbent layer subsequent to sample application was performed using mobile phase flow in the opposite direction (the input and output of the eluent was exchanged). The antibacterial effect of the fractions obtained from the stepwise gradient OPLC separation with the flow in the normal direction was evaluated by direct bioautography against two Gram-negative bacteria: the luminescence gene tagged plant pathogenic Pseudomonas syringae pv. maculicola, and the naturally luminescent marine bacterium Vibrio fischeri. The fractions having strong activity were analyzed by SPME-GC/MS and HPLC/MS/MS. Mainly essential oil components, coumarins, flavonoids, phenolic acids, and fatty acids were tentatively identified in the fractions.

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18

Purwanti, Sri, Wulan Tri Wahyuni, and Irmanida Batubara. "Antioxidant Activity of Daemonorops draco Resin." Jurnal Kimia Sains dan Aplikasi 22, no. 5 (2019): 179–83. http://dx.doi.org/10.14710/jksa.22.5.179-183.

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Jernang resin is secretion of jernang rattan (Daemonorops draco, Arecaceae family) fruits which is endemic in Southeast Asia. This resin has various biological activities and empirically used as wound healing, headache medicines, and fever remedies by Anak Dalam ethnic group from Jambi. This study was performed to evaluate the antioxidant activity of nonpolar fraction of D. draco resin which collected from Jambi Province, Sumatera, Indonesia. Resin was extracted with n-hexane, ethyl acetate, and methanol respectively. The antioxidant properties of the extracts were then evaluated using 1,1-diphenyl-2picryl-hidrazyl radical scavenging assay. The most active extract was further fractionated using n-hexane and methanol and separated using column chromatography and preparative thin layer chromatography. Separation of the extract was conducted through antioxidant assay-guided fractionation. Characterization of the active fraction was carried out by infrared spectroscopy. The result shows that ethyl acetate extract provides higher antioxidant activity (IC50 = 27.61 µg/mL) compare to methanol and n-hexane extracts. N-hexane fraction of ethyl acetate extract used for further separation using column and preparative thin layer chromatography due to its antioxidant activity. Separation using column chromatography resulting in 9 fractions (F.1-9). Fraction F.5 provide high antioxidant activity (IC50 = 17.27 µg/mL) and further separated using preparative thin layer chromatography resulting two fractions with lower antioxidant activity F.5.1 (IC50 = 85.18 µg/mL) and F.5.2 (IC50 = 34.94 µg/mL). Characterization of fraction F.5.2 using infrared spectroscopy showed that component in fraction F.5.2 contains NH-substituted benzene.

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19

Nugroho, Titania Tjandrawati, Krisna Puja, Yum Eryanti, and Miranti Miranti. "Fractionation of Garcinia Mangostana Fruit Pericarp Cellulase Assisted Extracts by Preparative Thin Layer Chromatography and High Performance Liquid Chromatography." Jurnal Natur Indonesia 18, no. 1 (2020): 31. http://dx.doi.org/10.31258/jnat.18.1.31-42.

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The polar extract of Mangosteen (Garcinia mangostana) fruit pericarp obtained by cellulase assisted ethanol extraction has strong antioxidant activity, giving an average 2,2 diphenyl-1 pykrylhydrazyl (DPPH) radical scavenging IC50 of 13.9 µg/mL. In order to elucidate the chemical component from this extract that is responsible for the high antioxidant activity, fractionation of the extract should firstly be performed. In this paper we show results of preparative fractionation of the polar extract by two methods, namely preparative Thin Layer Chromatography (PTLC) and preparative High Performance Liquid Chromatography (PHPLC). PTLC used Silica Gel G60 plates, with a hexane:ethyl acetate (6:4) eluent. PHPLC was a reverse phase method, using C18 column and water:acetonitrile gradient elution. 4 fractions from PTLC and 6 fractions from PHPLC were collected and their antioxidant activity analyzed. Both methods gave separated fractions with lower antioxidant activity than the unfractionated original crude extracts, showing that the strong antioxidant activity of Mangosteen pericarp polar extracts maybe due to the concerted synergetic effect of several compounds, rather than a single isolated compound. It also shows the high degree of difficulty in separating mangosteen pericarp polar components having antioxidant activity for further structural analysis.

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20

Wünsche, L., U. Keller, and I. Flament. "Combination of supercritical fluid chromatography with thin-layer chromatography on a semi-preparative scale." Journal of Chromatography A 552 (August 1991): 539–49. http://dx.doi.org/10.1016/s0021-9673(01)95970-9.

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21

Afrianto, Andika Wahyu, and Kanda Panthong. "Flavonoid Compound from Dichloromethane Extract of Crinum amabile Donn Leaves." Kaunia: Integration and Interconnection Islam and Science Journal 18, no. 1 (2022): 17–23. http://dx.doi.org/10.14421/kaunia.3399.

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Flavonoid compound was isolated from Crinum amabile Donn. leaves. The separation of flavonoids was carried out by using chromatographic techniques to purify CH2Cl2 extract of Crinum amabile Donn. leaves. Column chromatography with silica gel and sephadex as stationary phases, thin-layer chromatography, and preparative thin-layer chromatography were the chromatographic techniques used in this research. The pure compound obtained in the form of white-yellow solid with the Rf value is 0.44. Compound identification using 1H-NMR spectrometer showed the presence of protons from the CH=CH ortho with the appearance of a doublet of doublet (dd) each having j values of 8.5 Hz and 8.1 Hz with chemical shifts in the range of 6.5 ppm and 7 ppm. The CH=CH ortho group with the appearance of doublet of doublet of doublet (ddd) each having j values 8.4 Hz and 9 Hz with chemical shifts in the range of 7.2 ppm to 7.4 ppm. The methoxy group (-OCH3) was detected on chemical shift 3.8 ppm. Spectrometries of analysis showed that flavonoid compound obtained was 4-Hydroxy-7-Methoxyflavan.

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22

J. Khadim, Enas, Alaa A. Abdulrasool, and Zainab J. Awad. "Phytochemical Investigation of Alkaloids in the Iraqi Echinops heterophyllus (Compositae)." Iraqi Journal of Pharmaceutical Sciences ( P-ISSN 1683 - 3597 E-ISSN 2521 - 3512) 23, no. 1 (2017): 26–34. http://dx.doi.org/10.31351/vol23iss1pp26-34.

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Alkaloids are a group of naturally occurring chemical compounds that contain mostly basic nitrogen atoms . They are a large family of compounds synthesized by plants in addition to the bacteria, fungi, and animals, they often have pharmacological effects. The aim of this study is to isolate and identified alkaloids in a newly studied, wild Iraqi plant named Echinops heterophyllus. The medicinal importance of alkaloids, on one hand and the absence of any phytochemical investigation on heterophyllus species of echinops genus on the other hand , acquired this study its importance. Three alkaloids (named E1, E2 and E3) were isolated from seed plant part by two chromatographic methods: Preparative high Performance Liquid Chromatography (PHPLC) and preparative thin layer chromatography (PTLC), one of them identified as(1-Methyl-2,3-dihydro-4(1H)-quinolinone by different chemical analysis like: ultra violet spectrum analysis (UV spectrum), Fourier transforms infrared spectra (FT-IR) , elemental microanalysis (CHN) and Proton1H-NMR and carbon 13C-NMR analysis. Key words: Echinops, heterophyllus, quinoline alkaloids.

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23

Nyiredy, Sz, C. A. J. Erdelmeier, and O. Sticher. "Preparative separation of bipyridyl isomers using sequential centrifugal layer chromatography (SCLC)." Fresenius' Zeitschrift für analytische Chemie 321, no. 6 (1985): 556–58. http://dx.doi.org/10.1007/bf00464364.

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24

Lin, Bingchang, Tong Yun, Guoming Zhong, and Georges Guiochon. "Shock layer analysis for a single-component in preparative elution chromatography." Journal of Chromatography A 708, no. 1 (1995): 1–12. http://dx.doi.org/10.1016/0021-9673(95)00380-6.

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25

Tsydendambaev, V. D., V. P. Pchelkin, and A. G. Vereshchagin. "Preparative flow thin-layer chromatography of biomembrane higher fatty acid diglycerides." Pharmaceutical Chemistry Journal 42, no. 4 (2008): 228–31. http://dx.doi.org/10.1007/s11094-008-0087-9.

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26

Cherviakova, L., T. Panchenko, and O. Borzykh. "Analytical control of active substances of the class of imidazolinones in herbicide formulations." Karantin i zahist roslin, no. 1 (March 10, 2021): 15–18. http://dx.doi.org/10.36495/2312-0614.2021.1.15-18.

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Goal. The choice of a chromatographic method and the development of a method for the analytical determination of imazethapyr, imazamox, imazapyr in herbicide preparative forms in the joint presence. Methods. Active substances were analyzed by thin layer chromatography. The linear range of the dependence of the area of chromatographic zones on the amount of active substance was assessed by a mathematical-statistical method. Results. Determination of pesticides by thin-layer chromatography includes the main stages: classification of pesticides by polarity; extraction of active substances from the analyzed sample; chromatographic separation, detection and quantification. The decisive factor in the analysis stages is the dipole moment (μ, D), which characterizes the polarity of the compounds. Imazethapyr, imazamox and imazapir are polar compounds (μ≥6, D) with the corresponding values: 6.1; 6.4 and 6.8 D. Extraction of active substances is carried out with ethanol. Qualitative determination — in a thin layer of adsorbent silica gel in the mobile phase: a mixture of ethanol with acetic acid in a ratio of 4 : 1.5. Identify compounds at the wavelength of the spectrum λ 254 nm and using the developing reagent silver ammonia. The calibration dependence of the area of the chromatographic zone of the compound on its amount is linear in the detection range of 0.30—1.30 μg and is described by the regression equations for: imazethapyr S = 12.345 C + 0.7778, R2 = 0.99; imazapyr S = 9.3671 C + 1.081, R2 = 0.99; imazamox S = 7.6234 C + 1.4462, R2 = 0.98. The equation is used to quantify the active ingredients in the chromatogram. Conclusions. The use of the method of thin layer chromatography makes it possible to select selective conditions for the analysis of imazethapyr, imazamox, and imazapyr in the presence of herbicides in preparative forms. The developed technique is an express method of control and provides determination of active substances in the course of one analysis with high accuracy (relative error is less than 5% at n = 5, P = 0.95). The analytical support of the developed and patented method allows for analytical control of active substances of the imidazolinone class in the formulation of pesticides by analytical and toxicological laboratories, testing services without the use of expensive devices.

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27

Nigussie, Gashaw. "Isolation and Characterization of the Roots of Rumex nervosus." Journal of Tropical Pharmacy and Chemistry 5, no. 1 (2020): 39–50. http://dx.doi.org/10.25026/jtpc.v5i1.241.

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Rumex nervosus belongs to the family of Polygonaceae,which is traditionally used in Ethiopia to treat various diseases. This prompted us to isolate bioactive compounds from the root of this plant. Ground root parts of Rumex nervosus were subjected to exhaustive extraction successively with petroleum ether and methanol.The solvent from each extract was evaporated under reduced pressure using rotavapour to obtain petroleum ether and methanol extract. Chromatographic purification of the methanol extracts by Column chromatography followed by Preparative Thin layer Chromatography using Chloroform: methanol (9.5:0.5) ratio gave a compound coded as RN-6. The structure of this compound 4-ethylheptyl benzoate was characterized as by means of 1H NMR, 13C NMR, UV and IR spectral data.

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28

Gowtham M, Asharani I V, and Paridhavi M. "Isolation and characterization of components from roots of Premna latifolia Roxb." International Journal of Research in Pharmaceutical Sciences 10, no. 3 (2019): 2259–64. http://dx.doi.org/10.26452/ijrps.v10i3.1463.

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The aim of the current work was to isolate and characterize structurally fascinating and biologically intriguing compounds from the dried roots of Premna latifolia. Dried plant roots were subjected to soxhalation with ethyl alcohol and later to column chromatography. The individual compounds were isolated by preparative thin-layer chromatography followed by structural characterization using various spectral ways like LCMS, IR, 1D-NMR and 2D-NMR (1H-1H NMR and 1H-13C NMR). Three totally different compounds were isolated and characterised as Compound 1: n-Tridecanyl n-Tetracosanoate, Compound 2: Stigmanstan -3β-olyln-octadec-9ʹ, 12ʹ-dienoate and Compound 3: n-Tetracosanol for the first time from Premna latifolia roots.

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29

Padmathilake, K. G. E., H. M. S. K. H. Bandara, M. Mallique Qader, et al. "Talarofuranone, a New Talaroconvolutin Analog from the Endophytic Fungus Talaromyces purpurogenus from Pouteria campechiana Seeds." Natural Product Communications 12, no. 4 (2017): 1934578X1701200. http://dx.doi.org/10.1177/1934578x1701200406.

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An endophytic fungus Talaromyces purpurogenus was isolated from the seeds of the popular edible fruit Pouteria campechiana. The fungus was fermented in potato dextrose agar and the fungal media were extracted with EtOAc. Chromatographic separation of the EtOAc extracts over silica gel, Sephadex LH-20 and preparative thin layer chromatography furnished a furanone analogue of talaroconvolutin A, named talarofuranone (1), along with talaroconvolutin A (2), 4-hydroxyacetophenone, tyrosol and ergosterol. The structure of 1 was determined by comparing the NMR data with that of 2 and by HRFABMS.

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30

Rouillon, R., G. Gay, J. Bernillon, J. Favre-Bonvin, and G. Bruchet. "Analysis by HPLC – mass spectrometry of the indole compounds released by the ectomycorrhizal fungus Hebeloma hiemale in pure culture." Canadian Journal of Botany 64, no. 9 (1986): 1893–97. http://dx.doi.org/10.1139/b86-252.

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Indole compounds released by Hebeloma hiemale Bres. in pure culture were studied by cultivating the fungus on a nutrient solution supplemented or not with 1 mM tryptophan. Analytical thin-layer chromatography revealed numerous indole compounds in 7-week-old culture filtrates obtained in the presence of tryptophan. Such compounds were isolated by preparative thin-layer chromatography and purified by high performance liquid chromatography. The most abundant of them, i.e., indolyl-3-acetic acid, indolyl-3-carboxylic acid, and indole-3-aldehyde, were identified by mass spectrometry. Indole-3-aldehyde and indolyl-3-carboxylic acid, which were detected in filtrates throughout the culture period, might result from breakdown of indolyl-3-acetic acid by fungal exocellular enzymes.

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Farid, Yunahara, and Iswahyun Iswahyun. "ISOLATION, IDENTIFICATION, AND ANTIOXIDANT ACTIVITY OF CHEMICAL COMPOUND IN ETHANOL EXTRACT OF PAPAYA LEAVES (CARICA PAPAYA L.)." Asian Journal of Pharmaceutical and Clinical Research 11, no. 13 (2018): 118. http://dx.doi.org/10.22159/ajpcr.2018.v11s1.26583.

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Objective: The purpose of this research was to isolate and identify the active antioxidant compound in ethanol extract of papaya leaves (Carica papaya L.).Methods: The methods used were fractionation using vacuum liquid chromatography (VLC), and the active fraction was purified using column chromatography (CC). The pure isolate was obtained with preparative thin-layer chromatographic (TLC) identified by spectroscopy. Its antioxidant activity was evaluated using 2,2-diphenyl-picryl-hydrazyl. The presence of phenols was analyzed using ultraviolet (UV)-visible, Fourier-transform infrared (FTIR), and gas chromatography (GC)–mass spectrometry (MS).Results: The results showed that ethanol extract of papaya leaf has a strong antioxidant activity with IC50 value of 100.0±0.07 ppm. The result of VLC fractionation using mobile phase of chloroform-methanol indicated that the active fraction was EtOH.3 that has antioxidant activity with IC50 of 121.6±0.66 ppm. The purification using CC produced active fraction EtOH.3.3 with IC50 value of 176.4±0.76 ppm. After identified, the active isolate compound EtOH.3.3.1 from preparative TLC, the results of UV-visible spectrophotometry, FTIR spectrophotometry, and GC–MS show the presence of the phenol compounds.Conclusion: The ethanol extract has antioxidant activity and the extract was suspected to contain 2-methoxy-4-vinylphenol compound.

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Bahrami, S., H. Gasser, and H. Redl. "A preparative high performance liquid chromatography method for separation of lecithin: comparison to thin-layer chromatography." Journal of Lipid Research 28, no. 5 (1987): 596–98. http://dx.doi.org/10.1016/s0022-2275(20)38685-5.

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Skalska, Agnieszka, Anna Matysik, Marek Gerkowicz, and Magdalena Wójciak-Kosior. "Preparative reversed-phase high-performance thin-layer chromatography for analysis of anthocyanins." Journal of Planar Chromatography – Modern TLC 19, no. 112 (2006): 463–66. http://dx.doi.org/10.1556/jpc.19.2006.6.10.

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Rabel, Fred, and Joseph Sherma. "Review of the state of the art of preparative thin-layer chromatography." Journal of Liquid Chromatography & Related Technologies 40, no. 4 (2017): 165–76. http://dx.doi.org/10.1080/10826076.2017.1294081.

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Lee, Y. W., and C. E. Cook. "Preparative Separation of Demeton Isomers with Ito Multi-Layer Coil Countercurrent Chromatography." Journal of Liquid Chromatography 8, no. 12 (1985): 2253–58. http://dx.doi.org/10.1080/01483918508074129.

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Matysik, G., E. Soczewiński, and B. Polak. "Improvement of separation in zonal preparative thin-layer chromatography by gradient elution." Chromatographia 39, no. 7-8 (1994): 497–504. http://dx.doi.org/10.1007/bf02278768.

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Läufer, Konrad, Jochen Lehmann, Stefan Petry, Markus Scheuring, and Markus Schmidt-Schuchardt. "Simple, inexpensive system for using thin-layer chromatography for micro-preparative purposes." Journal of Chromatography A 684, no. 2 (1994): 370–73. http://dx.doi.org/10.1016/0021-9673(94)00571-0.

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Obaid, Noor S., and Widad M. Al-Ani. "Phytochemical Study of Iraqi Cydonia oblonga Miller Fruit." INTERNATIONAL JOURNAL OF DRUG DELIVERY TECHNOLOGY 12, no. 03 (2022): 1256–60. http://dx.doi.org/10.25258/ijddt.12.3.54.

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Quince (Cydonia oblonga) fruit has a lot of phytochemicals that draw the attention of many researchers nowadays for its important medicinal values. This study concerns the identification and isolation of two flavonoids (Astragalin) flavonol glycoside and (Isorhamnetin) from fruit ethyl acetate extract of Iraqi cultivated Cydonia oblonga. The identification was carried out by thin layer chromatography (TLC) and high performance liquid chromatography (HPLC) analysis techniques. The yield of isolated compound was (1.6 and 1.3 %) for astragalin and isorhamnetin, respectively. This was achieved by using preparative thin layer chromatography glass plate (20×20) cm. This is followed by structure elucidation of isolated compounds through fourier transform infrared (FT-IR), ultraviolet (UV), nuclear magnetic resonance (1HNMR) and carbon-13 nuclear magnetic resonance (13CNMR). analysis procedures.

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Megawati, Megawati, Akhmad Darmawan, and Sofa Fajriah. "Cytotoxic Activity of Flavonoid Compounds Isolated from Tetrameles Nudliflora Leaves." ANNALES BOGORIENSES 23, no. 2 (2020): 81. http://dx.doi.org/10.14203/ann.bogor.2019.v23.n2.81-86.

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Tetrameles nudliflora is one of the endemic plants in Wallace region, especially in Mekongga Forest, Southeast Sulawesi, Indonesia. As part of our project in the field of natural drug discovery based on local bioresources, this study aimed to isolate secondary metabolite compounds from the ethyl acetate fractions of the leaves of T. nudiflora and evaluate their cytotoxic activities against breast carcinoma cancer lines, MCF-7. The methods used were various chromatography techniques such as vacuum column chromatography, gravitation column chromatography, thin layer chromatography, preparative thin layer chromatography, and re-crystallization using two different organic solvents. In the present study, two flavonoid compounds, kaempferol (1) and quercetin (2) were identified. The structures of 1-2 were determined using serial spectroscopic techniques, including mass spectrometry, one- and two-dimensional nuclear magnetic resonance. Moreover, using 3-(4,5-dimethylthiazol-2-yl)-2,5 diphenyl tetrazolium bromide (MTT) assay method, both compounds showed in vitro cytotoxic activity IC50 of 34.162 and 133.148 μg mL-1, respectively against MCF-7 cell lines.

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Jalmakhanbetova, R. I., Ye M. Suleimen, N. Abe, et al. "Isolation and in silico SARS-CoV-2 main protease inhibition potential of chrysoeriol from Chondrilla brevirostris Fisch. & C.A. Mey." Bulletin of the Karaganda University. "Chemistry" series 105, no. 1 (2022): 78–85. http://dx.doi.org/10.31489/2022ch1/78-85.

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The genus Chondrilla L. comprises 22 species on the CIS territory. 16 species of them grow in Kazakhstan. All species of the genus Chondrilla L. are rubber-bearing herbaceous plants that belong to the Asteraceae family. We picked Chondrilla brevirostris Fisch. & C.A. Mey. for the chemical study. It is a perennial herb that grows in desert steppes and forest meadows. The aboveground parts of Ch. brevirostris were extracted with ethanol at room temperature. Several fractions were obtained by separating ethanol extract on column chromatography. Rechromatography and preparative thin-layer chromatography were used to further study the obtained fractions and the isolation of flavonoids. As a result of preparative thin-layer chromatography, the flavonoid 5,7,4'-trihydroxy-3'-methoxyflavone (compound 1) was isolated. The chemical structure of 1 was established by spectroscopic data. Compound 1 was isolated for the first time from the species of Chondrilla. Compound 1 was subjected to a molecular docking study against COVID–19 main protease (Mpro) to investigate its expected activity against SARS-CoV-2. In this case, the substance showed a good binding mode with a free energy of –6.22 kcal/mol, while the binding energy of the co-crystallized ligand was –7.83 kcal/mol

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Nurhayati, Awik Puji Dyah, Rarastoeti Pratiwi, Subagus Wahyuono, and Istriyati . "PROLIFERATION INHIBITORY ACTIVITY OF THE ACTIVE FRACTION MARINE SPONGE Cinachyrella sp. AGAINST CELL LINE T47D." KnE Life Sciences 2, no. 1 (2015): 663. http://dx.doi.org/10.18502/kls.v2i1.243.

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<p>Marine sponges Cinachyrella sp. (Family:Tetillidae) in Kukup beach, Kemadang Village, Tanjungsari District, Gunung Kidul, DIY were producing diversity secondary metabolites such as polyketides, alkaloids, peptide and terpene. The purpose of this study was investigated proliferation inhibitory activity of active fraction Cinachyrella sp. against cell line T47D. Sponges samples were collected manually from rocky substrate at depth 0.5 m. The sponges was minced and extracted with 95% ethanol. The ethanol extract was partitioned sequentially with ethyl acetate. The extract ethyl acetate was fractionation with 4 organic solvent, in increasing order of polarity with vacuum liquid chromatography column (VLC) method. Doubling time method was applied to analyse the inhibition proliferative cell line T47D. Resulted showed ethyl acetate extract of Cinachyrella sp. were 12 fractions and all tested fraction obtained by thin layer chromatography (TLC). Fractions that have the same value Rf grouped together to obtain 6 fractions. The fraction number 5 exhibited proliferation inhibitory activity to cell line T47D. The Rf value of active fraction number 5 were 0.125; 0.25 and 0.437. The active fraction 5 than isolation by preparative thin-layer chromatography (PTLC) was 5 isolate fractions preparative. The isolate fractions preparative number 5 exhibited proliferation inhibitory activity against cell line T47D. Fraction which determined by cerium sulfate and results was expressed terpene and alkaloid. <br /><strong></strong></p><p><strong>Keywords</strong>: Cinachyrella sp., Doubling time method, proliferation inhibitory activity.</p>

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Kwiatkowska, Magdalena, Alicja Wzorek, Anna Kolbus, et al. "Flurbiprofen: A Study of the Behavior of the Scalemate by Chromatography, Sublimation, and NMR." Symmetry 13, no. 4 (2021): 543. http://dx.doi.org/10.3390/sym13040543.

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2-(2-Fluoro-4-biphenyl) propionic acid (flurbiprofen), from the phenylalkanoic acid family of nonsteroidal anti-inflammatory drugs (NSAID’s), is currently on the pharmaceutical market as a racemate. This racemic compound was tested for its propensity to undergo the self-disproportionation of enantiomers (SDE) phenomenon by various forms of chromatography (SDEvC), such as routine gravity-driven column chromatography, medium-pressure liquid chromatography (MPLC), preparative thin-layer chromatography (PTLC), and size-exclusion chromatography (SEC), as well as by sublimation (SDEvS). Furthermore, examination by nuclear magnetic resonance (NMR) in various solvents found that flurbiprofen exhibited the phenomenon of self-induced diastereomeric anisochronism (SIDA). By measurement of the diffusion coefficient (D), the longitudinal relaxation time (T1), and the transverse relaxation time (T2) using NMR, as well as by electrospray ionization-mass spectrometry (ESI-MS) examinations, the preferred intermolecular association was found to be solvent dependent, e.g., heterochiral association was preferred in toluene, while homochiral association was preferred in more polar solvents. This study also attempted, unsuccessfully, to correlate the NMR measurements of flurbiprofen with chromatographic outcomes for the rationalization and prediction of chromatographic results based on NMR measurements. Because the intermolecular hydrogen bonding of the acid groups in flurbiprofen overwhelmingly predominates over other intermolecular interactions, flurbiprofen seemed to represent a good test case for this idea. The behavior of scalemic samples of flurbiprofen is important, as, although it is currently dispensed as a racemate, clinical applications of the R enantiomer have been investigated. SDEvC and SDEvS both have ramifications for the preparation, handling, and storage of enantioenriched flurbiprofen, and this concern applies to other chiral drugs as well.

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Elisa, Gebby, Marline Nainggolan, and Ginda Haro. "Skrining Fitokimia dan Isolasi Senyawa Triterpenoid/Steroid dari Daun Buni (Antidesma Bunius (L.) Spreng.)." Talenta Conference Series: Tropical Medicine (TM) 1, no. 1 (2018): 271–76. http://dx.doi.org/10.32734/tm.v1i1.78.

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Salah satu tumbuhan yang digunakan dalam pengobatan secara tradisional adalah buni (Antidesma bunius (L.) Spreng.), yang dapat mengobati darah tinggi, jantung berdebar cepat, anemia, sifilis, antikanker, antiradikal dan sebagai bahan pewarna alami. Daun buni mengandung sejumlah triterpenoid/steroid, saponin dan flavonoid. Senyawa triterpenoid/steroid menunjukkan aktivitas farmakologi berupa antibakteri, antiinflamasi, inhibisi terhadap sintesis kolesterol, antikanker, antitumor dan aktivitas sitotoksik terhadap sel pangkreatik.Tujuan penelitian ini untuk melakukan skrining fitokimia dan mengisolasi senyawa triterpenoid/steroid dari daun buni (Antidesma bunius (L.) Spreng.). Simplisia daun buni dilakukan skrining fitokimia kemudian diekstrasi dengan cara maserasi menggunakan pelarut n-heksana, kemudian maserat diuapkan dengan alat penguap vakum putar. Ekstrak n-heksana yang diperoleh diisolasi dengan cara kromatografi lapis tipis (KLT) dan KLT preparatif menggunakan fase diam silika gel GF254 dan fase gerak yang sesuai. Isolat yang diperoleh diuji kemurniannya dengan KLT 2 arah dan dilanjutkan mengidentifikasi isolat dengan spektrofotometer ultraviolet dan spektrotometer inframerah. Hasil uji skrining fitokimia diperoleh senyawa glikosida, saponin, flavonoid dan triterpenoid/steroid. Hasil KLT ekstrak n-heksan dengan fase gerak n-heksana-etilasetat (70:30) diperoleh 4 noda dengan penampak noda Liebermann-Burchard, selanjutnya ekstrak n-heksan dipisahkan dengan KLT preparatif, diperoleh 1 (satu) isolat murni berwarna merah ungu (Rf 0,90). Hasil karakterisasi isolat peroleh panjang gelombang 203,2 nm dan dijumpai adanya gugus hidroksil, gugus -CH alifatis, ikatan C=C, gugus –CH2 dan gugus C-O. One of plants used for traditional medication is buni (Antidesmabunius (L.) Spreng.) which can be used for treatment of hypertension, rapid heartbeat, anemia, syphilis, and asanti-cancer, anti-radical, and can be used as natural dye. Buni leaves contain triterpenoid/steroid, saponin and flavonoid. Triterpenoid/steroid showpharmacology activities such as anti-bacteria, anti-inflammatory, inhibition to cholesterol synthesis, anti-cancer, anti-tumor, and cytotoxic activity to pancreatic cells. This research objectives were to conduct phyochemical screening and to isolate the triterpenoid/steroid from buni leaves (Antidesmabunius (L.) Spreng.The phytochemical screening of Buni leaves simplicia was conducted and thenextracted using maceration method with n-hexane and evaporated using rotary evaporator. The n-hexane extract was subjected to isolation with thin-layer chromatography and preparative thin-layer chromatography using stationaryphase of silica gel GF 254 and suitable mobile phase. The isolates obtained was taken into purity test using two dimensions thin-layer chromatography and identified with ultraviolet and infrared spectrophotometers. The phytochemical screening test showed the presence ofglycosides, saponins, flavonoids, and triterpenoids/steroids. The thin-layer chromatography of n-hexane extractwith n-hexane-ethyl acetate as mobile phase (70:30)showed 4spotsafter sprayed with Liebermann-Burchard. The n-hexane extract was further fractionated with preparative thin-layer chromatography and 1 pure purple-red isolate (Rf 0.90) was obtained. The characterization of isolate showed that the wave length was203.2 nm with hydroxyl group, –CH aliphatic group, C=C group, –CH2 group, and C–O group.

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Moschidis, Michael C. "Thin Layer Chromatographic and Infra Red Spectral Evidence for the Presence of Phosphonolipids in Cicada oni." Zeitschrift für Naturforschung C 42, no. 9-10 (1987): 1023–26. http://dx.doi.org/10.1515/znc-1987-9-1002.

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Abstract The phosphonolipids from whole Cicada oni have been isolated by preparative thin-layer chromatography (TLC) in methanol-water (2:1, v/v) and have been identified by TLC, infra-red spectroscopy, phosphono phosphorus determinations and elemental microanalyses. The presence has been confirmed of the phosphono analogues of phosphatidyl choline, phosphatidyl ethanolamine, sphingomyelin and of ceramide aminoethyl phosphonate.

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Kwok, David W. K., Gopalakrishna Pillai, Radana Vaughan, James E. Axelson, and Keith M. McErlane. "Preparative High-Performance Liquid Chromatography and Preparative Thin-Layer Chromatography Isolation of Tocainide Carbamoyl-Glucuronide: Structural Characterization by Gas Chromatography-Mass Spectrometry and Fast Atom Bombardment-Mass Spectrometry." Journal of Pharmaceutical Sciences 79, no. 10 (1990): 857–61. http://dx.doi.org/10.1002/jps.2600791002.

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46

Waksmundzka-Hajnos, Monika, Maria Gadzikowska, and Michał Hajnos. "Strategy for preparative separation of quaternary alkaloids fromChelidonium majusL. by thin-layer chromatography." Journal of Planar Chromatography – Modern TLC 15, no. 4 (2002): 289–93. http://dx.doi.org/10.1556/jpc.15.2002.4.9.

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Maître, Jean-Michel, Gilles Boss, Bernard Testa, and Kurt Hostettmann. "Preparative separation of diastereoisomeric 2-arylpropionic acid derivatives by centrifugal thin-layer chromatography." Journal of Chromatography A 356 (January 1986): 341–45. http://dx.doi.org/10.1016/s0021-9673(00)91496-1.

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Snini, A., A. Fahimi, Z. Mouloungui, M. Delmas, and A. Gaset. "Separation and preparative isolation of phenolic dialdehydes by on-line overpressured layer chromatography." Journal of Chromatography A 590, no. 2 (1992): 369–72. http://dx.doi.org/10.1016/0021-9673(92)85401-e.

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Jindrich, Jindrich, Josef Pitha, and Bengt Lindberg. "Separation of cyclodextrins and their derivatives by thin-layer and preparative column chromatography." Carbohydrate Research 275, no. 1 (1995): 1–7. http://dx.doi.org/10.1016/0008-6215(95)00071-z.

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Nguyen, Tuong Van, and Vinh Dinh. "Isolation of Kaempferol from Vietnamese Ginkgo biloba Leaves by Preparative Column Chromatography." Asian Journal of Chemistry 32, no. 3 (2020): 515–18. http://dx.doi.org/10.14233/ajchem.2020.22241.

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The aim of this research was to develop a simple procedure to isolate kaempferol from Ginkgo biloba leaves extract. Flavonoids present in Ginkgo biloba leaves were extracted by 96 % ethanol. These flavonol glycosides which were hydrolyzed in the presence of HCl to convert to aglycones. The flavonol aglycones were extracted by the hydrolysis of solution with ethyl acetate which was evaporated to dryness under reduced pressure to obtain concentrated flavonol aglycones (C2). Flavonol aglycones were then purified by preparative column chromatography with a mobile phase composed of petroleum ether-ethyl acetate to acquire fraction C3. The recrystallization of fraction C3 in acetone realizes to have an amorphous sediment as fraction C4 that was supposed to be a mixture of kaempferol, quercetin and isorhamnetin. Kaempferol in this sediment was purified by column chromatography with a mobile phase composed of CHCl3-MeOH to achieve a fraction denoted as fraction C5. The isolated fraction C5 was assigned by its purity and structure by thin layer chromatography (TLC), high performance liquid chromatography (HPLC) and spectroscopic data analyses.

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