Showing papers on "Thin-layer chromatography published in 2017"

Phytochemicals: Extraction methods, identification and detection of bioactive compounds from plant extracts

Abstract: Plants are recognized in the pharmaceutical industry due to their broad spectrum of structural diversity and their wide range of pharmacological activities. The biological active compounds that are present in plants referred as phytochemicals. These phytochemicals derived from different parts of plants such as leaves, barks, seed, seed coat, flowers, roots and pulps and thereby used as sources of direct medicinal agents. Phytochemistry describes the large number of secondary metabolic compounds present in the plants. The plants are the reservoirs of naturally occurring chemical compounds and of structurally diverse bioactive molecules. The extraction of bioactive compounds from the plants and their quantitative and qualitative estimation is important for exploration of new biomolecules to be used by pharmaceutical and agrochemical industry directly or can be used as a lead molecule to synthesize more potent molecules. This review mostly highlighted on the analytical methodologies, which includes the extraction methods and the analysis of bioactive compounds present in the plant extracts through the various techniques involving the applications of chromatographic techniques such as HPLC (High Performance Liquid Chromatography), TLC (Thin Layer Chromatography), HPTLC (High Performance Thin Layer Chromatography), OPLC (Optimum Performance Laminar Chromatography), GC (Gas Chromatography), PC (Paper Chromatography), CC (Column Chromatography) and it’s detection through Fourier Transform Infra-Red spectroscopy (FTIR), Nuclear Magnetic Resonance (NMR), and Mass Spectrometry (MS).

Thin-layer chromatography :a modern practical approach

Abstract: Thin-layer chromatography :a modern practical approach , Thin-layer chromatography :a modern practical approach , مرکز فناوری اطلاعات و اطلاع رسانی کشاورزی

Review of thin-layer chromatography in pesticide analysis: 2014–2016

Abstract: Publications reporting techniques and applications of thin-layer chromatography (planar chromatography) for the separation, detection, qualitative and quantitative determination, and preparative isolation of pesticides and their metabolites are reviewed for the period from November 1, 2014 to November 1, 2016. Analyses are described for a variety of sample types and pesticide classes. In addition to references on residue analysis, studies such as pesticide chromatographic retention, identification and characterization of natural pesticides, metabolism, bioactivity, degradation, soil mobility, and lipophilicity are covered. The unique advantages of thin-layer chromatography in presenting results as a stored image on an open stationary phase are addressed.

Chromatographic Techniques for Rare Earth Elements Analysis

Abstract: Abstract The present capability of rare earth element (REE) analysis has been achieved by the development of two instrumental techniques. The efficiency of spectroscopic methods was extraordinarily improved for the detection and determination of REE traces in various materials. On the other hand, the determination of REEs very often depends on the preconcentration and separation of REEs, and chromatographic techniques are very powerful tools for the separation of REEs. By coupling with sensitive detectors, many ambitious analytical tasks can be fulfilled. Liquid chromatography is the most widely used technique. Different combinations of stationary phases and mobile phases could be used in ion exchange chromatography, ion chromatography, ion-pair reverse-phase chromatography and some other techniques. The application of gas chromatography is limited because only volatile compounds of REEs can be separated. Thin-layer and paper chromatography are techniques that cannot be directly coupled with suitable detectors, which limit their applications. For special demands, separations can be performed by capillary electrophoresis, which has very high separation efficiency.

Thin-Layer Chromatography to Separate Phospholipids and Neutral Lipids from Yeast.

Abstract: Thin-layer chromatography (TLC) is a versatile technique for the separation of lipid classes. It provides excellent resolution, can be used for both preparative and analytical applications, and does not require expensive equipment. Here we describe the use of different solvent systems to separate yeast phospholipids and neutral lipids by TLC in one dimension. Resolved lipid species are visualized by iodine vapor or by charring after treatment with sulfuric acid and manganese chloride. Neither of these staining techniques yields a quantitative readout because the mixture of various lipids in yeast affects iodine absorption and charring efficiency; standard curves are required to obtain semiquantitative estimates of the relative lipid composition.

Evaluation of Antioxidant Capacity and Identification of Bioactive Compounds of Crude Methanol Extracts of Caesalpinia pulcherrima (L.) Swartz

Abstract: The study was conducted to determine the antioxidant capacity, expressed as half maximal inhibitory concentration, IC50, of Caesalpinia pulcherrima leaf, flower and seed methanol extracts, and their correlation to their total phenolic, flavonoid and triterpenoid contents. Thin layer chromatographic profiling of the methanol extracts was also conducted followed by ultra-performance liquid chromatography quadruple time-of-flight mass spectrometric analysis for the identification of antioxidant compounds. Based on the quantitative antioxidant assays, all extracts exhibited comparable activity with the reference standard at 800 µg/ml (P>0.05). Correlation data revealed a strong negative correlation between the IC50 and the total phenolic, flavonoid and triterpenoid contents of the extracts, with statistically significant negative correlations observed between the flavonoids of leaf (r=–0.997) and flower¬ (r=–0.998) with reducing power assay, and triterpenoids of flower (r=–1.000) with 2,2-diphenyl-1-picrylhydrazyl scavenging assay. Two common spots with antioxidant activity in the thin layer chromatography profiles were subjected to ultra-performance liquid chromatography quadruple time-of-flight mass spectrometric. The majority of compounds were identified in the library as triterpenoids, flavonoids and phenolics, and still a large quantity of compounds were unidentified. Hyperforin, 3-(4'-hydroxy-benzyl)-5,7-dihydroxy-6,8-dimethyl-chroman-4-one and platycodigenin were identified to be the common compounds present on the three plant parts.

Review on Thin Layer Chromatography

Abstract: Thin-layer chromatography (TLC) is a technique which is used to distinct non-volatile mixtures. This Thin-layer chromatography is can be executed on a sheet of glass, plastic, or aluminium foil, which is covered with a thin layer of adsorbent material, usually silica gel, cellulose or aluminium oxide (alumina). In this, the layer of adsorbent is called as the stationary phase. Chromatography is a division procedure that each natural scientist and organic chemist knows about.

Characterization of the phenolic compound, gallic acid from Sansevieria roxburghiana schult and schult. f. rhizomes and antioxidant and cytotoxic activities evaluation

Abstract: Background Sansevieria roxburghiana Schult. and Schult. f. (Asparagaceae) grows in India, Indonesia, Sri Lanka, and tropical Africa. Even though the plant has been traditionally used for the treatment of many ailments, the antioxidant and antiproliferative activities of S. roxburghiana methanol extract and its fractions have not yet been explored. Materials and methods Quantitative estimation of phenols and different antioxidant assays were performed using standard methods. Anti-proliferative effect of the extract and fractions were evaluated in HCT-116, HeLa, MCF-7, HepG2, and A-549 cancer cell lines by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and sulforhodamine B (SRB) assay methods. High-performance liquid chromatography (HPLC) and high-performance thin layer chromatography (HPTLC) fingerprint profiling were carried out for extract and different fractions. Results Significant antioxidant and anti-proliferate activity were detected in ethyl acetate fraction. Ethyl acetate fraction showed prominent scavenging activity in 1,1-diphenyl-2-picrylhydrazyl, 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt, and nitric oxide antioxidant assays with an concentration yielding 50% inhibition (IC50) 15.33 ± 1.45, 45.3 ± 1.93 and 48.43 ± 0.46 mg/ml, respectively. Cytotoxicity of ethyl acetate fraction was the highest among other fractions against HCT-116, HeLa, and MCF-7cancer cell lines with IC50 values 16.55 ± 1.28, 12.38 ± 1.36, and 8.03 ± 1.9 μg/ml, respectively, by MTT assay and 15.57 ± 0.70, 13.19 ± 0.49, and 10.34 ± 0.9 μg/ml, respectively, by SRB assay. The presence of gallic acid in the ethyl acetate fraction of S. roxburghiana rhizomes was confirmed by HPLC and HPTLC analysis. Conclusion Results suggested that ethyl acetate fraction exhibited effective antioxidant and antiproliferative activities. The phenolic compounds identified in ethyl acetate fraction could be responsible for the activities. Summary Sansevieria roxburghiana has been selected for in vitro antioxidant and cytotoxicity screeningEthyl acetate fraction of methanol extract of S. roxburghiana exhibited effective antioxidant and antiproliferative activitiesThe activity of ethyl acetate fraction may be due to the presence of phenolic compound which is identified by high-performance liquid chromatography and high-performance thin layer chromatography techniques. Abbreviations used: %: Percent, oC: Celsius, mg: Microgram, ml-Microlitre, ANOVA: Analysis of variance, DMSO: Dimethyl sulfoxide, g: Grams, IC50: Concentration yielding 50% inhibition, Kg: Kilogram, mg: Milligram, min: Minutes, ml: Milliliter, HPLC: High-performance liquid chromatography, HPTLC: High-performance thin layer chromatography, DPPH: 1,1-diphenyl-2-picrylhydrazyl, ABTS: 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt, MTT: 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide, GAE: Gallic acid equivalents, SRME: Methanol extract of S. roxburghiana, ROS: Reactive oxygen species, SRPE: Petroleum ether fraction of S. roxburghiana, SREA: Ethyl acetate fraction of S. roxburghiana, SRAQ: Aqueous fraction of S. roxburghiana, DMEM: Dulbecco's Minimum Essential Medium, FBS: Fetal bovine serum, OD: Optical density, TPC: Total phenolic content, SRBU: Butanol fraction of S. roxburghiana.

Two-dimensional thin-layer chromatography of 17α-ethinylestradiol on RP-18 W plate, detected by effect-directed analysis using the YES test

Abstract: We present a two-dimensional (2D) planar chromatographic separation of estrogenic active compounds on RP-18 W (Merck, 1.14296) phase. A mixture of 8 substances was separated using a solvent mix consisting of hexane, ethyl acetate, acetone (55:15:10, v/v) in the first direction and of acetone and water (15:10, v/v) in the second direction. Separation was performed on an RP-18 W plate over a distance of 70 mm. This 2D-separation method can be used to quantify 17α-ethinylestradiol (EE2) in an effect-directed analysis, using the yeast strain Saccharomyces cerevisiae BJ3505. The test strain (according to McDonnell) contains the estrogen receptor. Its activation by estrogen active compounds is measured by inducing the reporter gene lacZ which encodes the enzyme β-galactosidase. This enzyme activity is determined on plate by using the fluorescent substrate MUG (4-methylumbelliferyl-β-d-galactopyranoside).

Effective separation of organic dyes using ionic liquids as green mobile phase and polyaniline-modified silica gel nanocomposite-based thin-layer chromatography

Abstract: Organic dyes are used for a wide variety of purposes including their applications in textiles, foods, printing cosmetics and pharmaceuticals. Thus, these are industrially very important and their analysis is always required before putting to particular use. To develop the extremely efficient thin layer chromatographic system for the resolution of co-existing dyes, the silica gel was modified with the conducting polymer polyaniline. Silica gel and polyaniline modified silica gel were used as stationary phase while the different formulations based on aqueous solutions of ionic liquids such as 1-methyl-imidazolium chloride, 1,2,3-trimethylimidazolium methyl sulphate and 1-ethyl 3-methyl-imidazolium tetrafluoroborate were used as mobile phase to study the migration behaviour of organic dyes. Comparatively better separation efficiency was observed in case of polyaniline modified silica gel with respect to unmodified silica gel. Densitogrpahic presentation of separation of organic dyes achieved using polyaniline modified silica gel (Pani@SG-ES) was also presented. The thin layer chromatographic system comprising of polyaniline modified silica gel (Pani@SG-ES) as stationary phase and 2% aqueous 1- methyl-imidazolium chloride as green mobile phase was observed to be most efficient towards separation of several three-component mixtures of organic dyes. The effect of presence of impurities on the efficiency of separation was examined and the detection limits of the dyes were also calculated. Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM with EDX) and transmission electron micrograph (TEM) studies were undertaken to characterize silica gel and polyaniline modified silica. A new thin layer chromatographic system consisting of polyaniline modified silica gel (S2) as stationary phase with 2 % aqueous (1-methylimidazolium chloride) as eco-friendly mobile phase is most favourable for the identification and separation of three-component mixtures of organic dyes.

Qualitative and quantitative determination of main alkaloids of Chelidonium majus L. using thin-layer chromatographic-densitometric method

Abstract: We present a new simple thin-layer chromatographic method designed for determination of the main alkaloids of Chelidonium majus L. In this study, we used roots and herb of the plant collected in spring and autumn. The alkaloid fractions were prepared according to modified pharmacopeial procedure [1]. In our method, we performed two-step elution onto silica gel plates. The first eluent consisted of chloroform, methanol, and water mixed with 70:30:4 proportion. The second eluent comprised of toluene, ethyl acetate, and methanol with 83:15:2 proportion. The described thin-layer chromatography (TLC) system allows qualitative and quantitative determination of the following alkaloids: sanguinarine, chelerythrine, chelidonine, coptisine, and berberine. For determination of protopine, eluent with n-buthanol, acetic acid, and water in 15:1.5:4 proportion was investigated. The dominant alkaloids observed in studied fractions were coptisine (1027.096 ± 13.367–287.474 ± 3.069 mg/100 g dry matter ± sdv) and chelidonin...

Unconventional TLC Systems in Lipophilicity Determination: A Review

Abstract: This review focuses on four unusual thin-layer chromatography (TLC) approaches for the determination of lipophilicity: (1) the use of medium-polar stationary phases: CN, NH2, and DIOL instead of RP plates, together with water-based mobile phase; (2) the use of silica gel in a typical normal-phase manner and treating extrapolated retention indices as the “reversed lipophilicity”; (3) the use of oil impregnated silica gel in the reversed-phase manner; and (4) the use of salting-out mobile phases. The chromatographic indices obtained in these systems are numerously reported as well correlated with lipophilicity and they are an interesting alternative to classical RP systems approaches.

Characterization of nucleobases in sea buckthorn leaves: An HPTLC approach

Abstract: The present study aims to establish a high-performance thin layer chromatography (HPTLC)-based comparative analysis, directed toward characterization of nucleobases in aqueous and alcoholic extract...

Ultrasound-assisted Extraction of Ursolic Acid from the Flowers of Ixora coccinia Linn (Rubiaceae) and Antiproliferative Activity of Ursolic Acid and Synthesized Derivatives.

Abstract: Background: Ixora coccinea Linn (Rubiaceae) is an evergreen shrub with bright scarlet colored flowers found in several tropical and subtropical countries. It is used as an ornamental and medicinal plant. Phytochemical studies revealed that its major special metabolites are triterpene acids, such as ursolic and oleanolic acid. Objective: To evaluate the isolation of ursolic acid (UA) (1) from methanol extracts of I. coccinea flowers through two methodologies, to prepare four derivatives, and to evaluate the cytotoxic effect against six cancer cell lines. Materials and Methods: The UA was isolated from vegetal material by percolation at room temperature and by ultrasound-assisted extraction. The preparation of derivatives was performed according to literature methods, and the cytotoxic effects were evaluated using the MTT (3,4,5-dimethylthiazol-2-yl-2,5-diphenyltetrazolium bromide) assay. Results: The most efficient extraction was achieved through ultrasound irradiation with a yield of 35% after KOH-impregnated silica in chromatography column. Furthermore, four derivatives (3, 5, 6, 7) of UA were prepared and evaluated, including 1, against two lung cancer (A549 and H460) and four leukemia (K562, Lucena, HL60, and Jurkat) cell lines. Generally, results showed that 1 and 7 were the most active compounds against the assayed cell lines. Also, the cytotoxic effects observed on terpenes 1 and 7 were higher when compared with cisplatin, used as positive control, with the exception of Jurkat cell line. Conclusion: The efficiency of such an alternative extraction method led to the principal and abundant active component, 1, of I. coccinea, thus representing a considerable contribution for promising triterpenoid in cancer chemotherapy. Abbreviations used: MTT: 3,4,5-dimethylthiazol-2-yl-2,5-diphenyltetrazolium bromide, RP: reverse phase, TLC: thin layer chromatography, KOH: potassium hydroxide, IR: infrared, DMF: dimethylformamide, DMSO: dimethyl sulfoxide, TEA: triethylamine, RT: room temperature, EtOAc: ethyl acetate, MeOH: methanol, i-PrOH: iso-propanol, NMR: nuclear magnetic resonance, MDR: multiple drug resistance, RPMI: Roswell Park Memorial Institute

Purification and fractional analysis of methanolic extract of wedelia trilobata possessing apoptotic and anti-leukemic activity

Abstract: Background: Wedelia trilobata (L.) Hitch (WT), commonly known as yellow dots or creeping daisy, is a shrub possessing potent biological activities, and is traditionally used a medicinal plant in Ayurveda, Siddha and Unani systems of medicines, and it has also been tried against leukemia cell line MEG- 01. In the present study, purification and screening of the plant was done for bioactive compounds in methanolic extract of WT for apoptotic and antileukemia activity. Materials and methods: The methanolic extract of WT was initially purified through thin layer chromatography (TLC) and screened for the apoptotic and anti-leukemia activities. The positive band of TLC was subjected to silica gel column chromatography for further purification and the fractions obtained from it were screened again for antileukemia activity through thymidine uptake assay and apoptotic activity by DNA fragmentation, nuclear staining and flow cytometry assays. The fraction with positive result was subjected to HPLC for analysis of bioactive components. Results: Out of many combinations of solvents, the methanol and dichloromethane combination in the ratio 6:4 has revealed two bands in TLC, among which the second band showed positive results for apoptotic and anti-leukemic activities. Further purification of second band through silica gel chromatography gave five fractions in which the 3rd fraction gave positive results and it shows single peak during compositional analysis through HPLC. Conclusion: The single peak revealed through HPLC indicates the presence of pure compound with apoptotic and antileukemia activities encouraging for further structural analysis.

Synthesis of 2-hidroxyxanthone from xanthone as a basic material for new antimalarial drugs

Abstract: Objective: The purpose of this research is to synthesize 2-hydroxyxanthone from xanthone and to evaluate its antiplasmodial activity.Methods: The synthesis of 2-hydroxyxanthone followed the sequence of these synthetic stages, namely: 2-nitroxanthone, 2-aminoxanthone, and 2-hydroxyxanthone. The products were separated by chromatography methods including thin layer chromatography and vacuum liquid chromatography. Compound structures of the isolated products were determined based on their infrared and nuclear magnetic resonance spectra. To support these findings, the spectra were also matched to the corresponding data from literatures. The biological properties of the synthetic compound were evaluated toward Plasmodium falciparum 3D7.Results: 2-nitroxanthone was obtained as a brownish-yellow crystal in 69.00% yield with Madhya Pradesh of 181°C. Reduction of 2-nitroxanthone using SnCl2.2H2O/hydrogen chloride produced 2-aminoxanthone as a pale-yellow solid in 60.60% yield. Finally, the desired 2-hydroxyxanthone was achieved by initially reacting 2-aminoxanthone with sodium nitride to produce diazonium salt. Then, hydrolysis of the salt yielded 2-hydroxyxanthone as a white solid in 69.81% yield. Synthesis of 2-hydroxyxanthone from xanthone had an overall yield of38.35%. In vitro antiplasmodial assay against P. falciparum 3D7 showed that the half maximal inhibitory concentration value was 0.44 I¼g/mL.Conclusions: An antimalarial compound (2-hydroxyxanthone) was successfully synthesized from xanthone in three steps of synthetic reactions, i.e., the formation of 2-nitroxanthone, 2-aminoxanthone, and 2-hydroxyxanthone.Â