Showing papers on "Thin-layer chromatography published in 2020"

Acetylcholinesterase Inhibitors among Zingiber officinale Terpenes—Extraction Conditions and Thin Layer Chromatography-Based Bioautography Studies

Abstract: Although numerous studies have been conducted on ginger extracts and fractions, the data on the pharmacological activity of single constituents of Zingiber officinale are still insufficient. To assess the antidementia properties of the plant, a thin layer chromatography (TLC)-based bioautography acetylcholinesterase inhibitory assay was performed on the Zingiber officinale diethyl ether extract. It led to the recognition of three active inhibitors among volatile constituents of the plant: ar-curcumene (A), α-sesquiphellandrene (B) and a-zingiberene (C). The identification of the components was possible thanks to the application of a TLC-HPLC-MS interface analysis of active zones and the GC-MS qualitative analysis of the tested samples. Based on the obtained results, the influence of several extraction techniques (hydrodistillation-HD, pressurized liquid extraction or accelerated solvent extraction-ASE, shaking maceration-SM, supercritical fluid extraction-SFE, and ultrasound-assisted extraction-UAE) on the recovery of the active metabolites from plant material was assessed to deliver enriched extracts. As a result, HD and SFE, were found to be the most efficient methods to recover the volatile components and the concentrations of A, B, and C reached 0.51 ± 0.025, 0.77 ± 0.045, and 1.67 ± 0.11 percent, respectively. Only HD and SFE were found to recover monoterpene hydrocarbons from the plant matrix. The remaining techniques provided extracts rich in more complex constituents, like sesquiterpenes.

Plant Steroids: Occurrence, Biological Significance and their Analysis

Abstract: Plant steroids constitute a diverse group of natural products. Biosynthetically, they are derived from S-squalene-2,3-epoxide via acetate-mevalonate pathway. Among the plant steroids, phytosterols are ubiquitous in the plant kingdom. It is significant that some phytosterols have been reported to possess hypocholesterolemic activity. Withanolides are a large group of steroidal lactones with various biological activities. Brassinosteroids are a small group of plant steroids exhibiting plant growth hormonal activity. Phytoecdysteroids are polyhydroxylated plant steroids, many of which are known to exhibit anabolic effects with no undesirable side effects. Steroidal alkaloids are nitrogen-containing plant steroids with an array of biological activities. It is noteworthy that trace amounts of cholesterol and mammalian steroidal hormones including progesterone have been detected in some plants. Analyses of plant steroids mainly utilize chromatographic methods such as thin-layer chromatography (TLC), high performance liquid chromatography (HPLC), ultra high performance liquid chromatography (UHPLC), and gas liquid chromatography (GLC), while photodiode array (PDA), evaporative light scattering (ELS), and fluorescence (FL) detectors and mass spectrometry (MS) are commonly used for their detection, quantification, and identification. Some less common techniques employed for the analyses of plant steroids are immunoassays and biological assays. Keywords: plant steroids; occurrence; biological activity; analysis; thin-layer chromatography; high performance liquid chromatography; gas liquid chromatography; mass spectroscopy; biological assay; immunoassay

HPLC coupled with electrospray ionization multistage MS/MS and TLC analysis of flavones-C-glycosides and bibenzyl of Dendrobium hercoglossum.

Abstract: Dendrobium hercoglossum Rchb. f. (D. hercoglossum), as one of the origins of medicinal Dendrobium, has been widely used as a health food and nutrient source promoting fluid production. Due to a lack of quality control, it is often counterfeited or mixed with other Dendrobium. In this study, a high-performance liquid chromatography characteristic chromatogram method is established for the quality evaluation of D. hercoglossum. Based on the high-performance liquid chromatography characteristic chromatogram, D. hercoglossum is divided into two classes, each with different flavone peaks. These flavone peaks were identified using high-performance liquid chromatography coupled with electrospray ionization multistage tandem mass spectrometry. Among them, the acylated (3-hydroxy-3-methylglutaryl, p-coumaroyl, feruloyl, or sinapoyl) flavones-C-glycosides are first found in D. hercoglossum in this study. In addition, one unique band was found in D. hercoglossum by thin-layer chromatography, which can be used to distinguish it from other Dendrobium species as a characteristic marker of this plant. Combining the high-performance liquid chromatography characteristic chromatogram and high-performance liquid chromatography coupled with electrospray ionization multistage tandem mass spectrometry, the unique band was identified as 4,5-dihydroxy-3,3'-dimethoxybibenzyl. These analysis methods can be applied for the quality control and identification of D. hercoglossum as well as providing reference for the identification of similar constituents in other Dendrobium species.

Analysis of organic acids

Abstract: Organic acids are the organic compounds with the acidic properties, classified based on the number of carboxylic functions. In general, organic acids are weak acids. However, organic acids with phenol, enol, alcohol, and thiol groups are weaker than carboxylic acids. Organic acids vary in the number of hydroxy or carboxyl functional groups and carbon-carbon double bonds in their structures. The organic acids are categorized based on four characterizations: (1) the nature of carbon chain (aromatic, aliphatic, alicyclic, and heterocyclic); (2) saturation or unsaturation properties; (3) substituted or nonsubstituted features; and (4) the number of functional groups (mono, di- or tri-carboxylic). In the biological processes, organic acids are involved in numerous important pathways of metabolism and catabolism in animals and plants as the intermediate or final products, and play a main role in the tricarboxylic acid cycle or citric acid cycle (Krebs cycle), a vital pathway in eukaryotes and primary source of electrons donating to the mitochondrial respiratory membrane. Although these compounds are found in all organisms, plants have the unique ability to collect organic acids in cellular reactions. Organic acids affect fruits and vegetables' organoleptic properties such as color, flavor, and aroma. The current chapter will briefly introduce the organic acids in structures, physical, and chemical properties and discuss their Ethnopharmacology importance. Furthermore, the extraction techniques such as solid-liquid, ultrasound, microwave, accelerated liquid, supercritical fluid, and enzyme-assisted extraction will be reviewed. The purification techniques such as membrane separation, preparative high-performance liquid chromatography, counter-current chromatography, and thin layer chromatography are compared as well. As far as the identification and quantification techniques one would see gas chromatography, ion-exchange chromatography, capillary electrophoresis, high-performance liquid chromatography, nuclear magnetic resonance spectroscopy, and liquid chromatography-mass spectrometry. Finally, the levels of organic acids found in foods/plants and the effects of food processing on the phytochemicals are discussed.

Impregnated silica-based layers in thin layer chromatography

Abstract: Impregnated thin-layer chromatography (TLC) layers based on silica gel are presented. Impregnating agents such as metal cations, inorganic ions, chelating agents, chiral selectors, surfactants, ion...

Determination of Capsaicin Levels in Capsicum annum Linn Ethanolic Extract using Thin Layer Chromatography Analysis

Abstract: Active compounds of natural ingredients need to be extensively explored to determine their properties Capsicum annum Linn is widely grown in southern Asia and Southeast Asia This study aimed to determine the levels of capsaicin in C annum L ethanolic extract A total of 300 g C annum L analyzed in the form of powder and extract solution This study analysis performed thin layer chromatography (TLC) method to separate the adsorption on the adsorbent thin layer The ethanol used as a solvent to extract capsaicin The result showed that the capsaicin levels were found in the powder of 036% and extract solution of 184% The linear regression equation was y= 94571x + 54667, with R²= 09983, the capsaicin standard of 1020 µg/ml It can be concluded that the extract solution of C annum L had a greater capsaicin level than in the powder form

Extraction and molecular characterization of biological compounds from water hyacinth

Abstract: Eichhornia crassipes is an invasive aquatic plant whose individual morphological parts like roots and shoots were studied using different solvent extracts namely, benzene water and ethanol. All the solvent extracts of the root and shoot portions of the fresh Eichhornia crassipes were screened for the presence of various phytochemicals such as alkaloids, flavonoids, tannins, phenols, sterols, terpenoids, anthraquinones, and anthocyanins. The isolation and purification of the major bioactive compounds such as tannins and flavonoids were done by thin layer chromatography using the extract purified from column chromatography. The results from the Gas Chromatography showed the retention of many important phenolic and sterol based compounds, denoting their richness of bioactive compounds useful for pharmaceutical industries as drugs and environmental sectors thereby protecting the aquatic micro ecosystem.

Rapid Separation and Quantitative Analysis of Complex Lipophilic Wood Pulp Extractive Mixtures Based on 2D Thin Layer Chromatography

Abstract: We present a rapid method based on 2D thin layer chromatography (TLC) for the simultaneous separation and quantification of organic, lipophilic extractives occurring in lignocellulosic biorefinerie...

Analysis of other phenolics (capsaicin, gingerol, and alkylresorcinols)

Abstract: Phenolic compounds exhibit a wide variety of biological effects because of their antioxidant properties. Phenolic compounds have widespread occurrence in nature and are consumed by humans through diet consisting of fruits and vegetables. The gradually increasing interest in phenolic acids profile is directly proportional to their antioxidant activity and potential benefits for health as they protect the human body from free radicals and their formation is associated with normal natural metabolism of aerobic cells. Protective phenylpropanoid metabolism pathways in plants have been well-documented which results in the biosynthesis of phenolic compounds. The antiradical activity of phenolics and flavonoids is chiefly based on the reduction-oxidation properties of the hydroxyl group they contain as well as the structural relationships between different parts of the chemical structures of these compounds. Epidemiological data have exhibited various benefits of antioxidant compounds in the prevention of a wide range of disease states like cancer, cardiovascular disease, and neurodegenerative disorders. From the past few years, identification and development of phenolic compounds from various plants has become a major area of health and medical-related research studies. This chapter provides an updated and comprehensive overview on capsaicin, gingerol, and alkylresorcinols extraction, purification, and quantification as well as their antioxidant properties. The extraction of capsaicin, gingerol, and alkylresorcinols from source material is the first step involved in their analysis. They are extracted by solvent extraction, which is a conventional method, and modern methods such as subcritical fluid extraction (SFE) and ultrasonic-assisted extraction. The content of capsaicin, gingerol, and alkylresorcinols in the extract is determined using chemical, chromatographic, and spectrometric analysis. Thin layer chromatography (TLC), gas chromatography coupled with mass spectrometry (GC-MS), high performance liquid chromatography (HPLC), and liquid chromatography tandem mass spectrometry (LC-MS/MS) are employed for the identification and quantification of the individual compounds present.

Differences in the lipid patterns during maturation of 3T3-L1 adipocytes investigated by thin-layer chromatography, gas chromatography, and mass spectrometric approaches.

Abstract: Populations of industrialized countries have registered a dramatically increasing prevalence in obesity for many years. Despite continuous research, mechanisms involved in the storage and utilization of chemical energy in adipocytes are still under investigation. Adipocytes have the task to store excessive energy in the form of triacylglycerols (TG) and it is already well-known that the fatty acyl composition of TG is largely determined by the composition of the diet. In contrast to TG, the composition of adipocyte phospholipids was less comprehensively investigated. In this study, the compositions of the most abundant phospholipid classes of 3T3-L1 undifferentiated (preadipocytes) and differentiated cells (adipocytes) were determined. The lipid fractions were isolated by normal phase high-performance thin-layer chromatography and subsequently analyzed by electrospray ionization mass spectrometry. Additionally, the fatty acyl (FA) compositions were determined by gas chromatography. The positions of the FA residues were additionally confirmed by phospholipase A2 digestion. The advantages and disadvantages of the different analytical approaches will be discussed. It will be shown that undifferentiated 3T3-L1 and mature adipocytes differ extremely regarding their compositions. This goes along with an increase in odd-chain fatty acids. Graphical abstract.

Thin-layer chromatography-bioautographic method for the detection of arginase inhibitors

Abstract: Arginase represents a promising therapeutic target for various pathologies including inflammatory, cardiovascular, and parasitic diseases or cancers. In the current work, we report, for the first time, about the development of a thin-layer chromatography-based bioautography which can be used to rapidly detect arginase inhibitors in complex matrices such as plant extracts. The assay is based on the detection of urea produced by arginase using the coloring reagent α-isonitrosopropiophenone, resulting in the formation of a pink background on thin-layer chromatography plates. The assay conditions were optimized in order to provide sufficient contrast between the pink colored thin-layer chromatography plate and the clearer zones generated by the presence of arginase inhibitors. Different parameters were tested, such as incubation time and temperature, atmospheric conditions, as well as substrate and enzyme concentrations. This technique makes it possible to detect 0.1 μg of a known arginase inhibitor, Nω -hydroxy-nor-Arginine, after it has been spotted, either pure or mixed with a Myrtus communis methanolic fruit extract, and the plate has been developed in an appropriate solvent. The newly developed method was used to reveal the presence of an inhibitor in hempseed cakes (Cannabis sativa L.).

Rapid methods for the separation of natural mixtures of beauverolides, cholesterol acyltransferase inhibitors, isolated from the fungus Isaria fumosorosea

Abstract: Beauverolides (beauveriolides) are abundant, biologically active cyclodepsipeptides produced by many entomopathogenic fungi, including those that are used as biopesticides. Beauverolides act as cholesterol acyltransferase inhibitors in humans; thus, their mode of action has been the subject of pharmacological and clinical research. The cost-effective analytical methods are needed for fast, routine laboratory analysis of beauverolides. We isolated beauverolides from the fungal strain Isaria fumosorosea PFR 97-Apopka and opened the rings of the isolated beauverolides using a pyridine alkaline medium. We separated fractions of cyclic and linearized beauverolides by thin-layer chromatography, and found the chloroform-acetate (9:1, v/v) and chloroform-acetonitrile-acetate (8:1:1, v/v/v) mobile phases, respectively, to be the most efficient. We examined all the fractions by liquid chromatography-mass spectrometry using ion trap and Orbitrap high resolution mass spectrometry. For rapid screening of the contents of cyclic, and, particularly, linearized beauverolides, we developed a novel analytical method that consisted of using capillary electrophoresis coupled with contactless conductivity detection. Furthermore, we improved the separation of the peptides by applying capillary micellar electrokinetic chromatography with the N-cyclohexyl-2-aminoethanesulfonic acid:SDS:NaOH buffer, pH 9.8 as the background electrolyte. The described novel methods allow fast and cost-effective separation of chemically related groups of beauverolides.

Development and Validation of Chromatographic Methods for Simultaneous Determination of Paracetamol, Orphenadrine Citrate and Caffeine in Presence of P-aminophenol; Quantification of P-aminophenol Nephrotoxic Impurity Using LC-MS/MS.

Abstract: Three chromatographic methods were developed, optimized and validated for Paracetamol (PAR), Orphenadrine citrate (Or.cit) and Caffeine (CAF) determination in their mixture and in presence of PAR toxic impurity; P-aminophenol (PAP) in tablets. The first method is based on a thin layer chromatography combined with densitometry. Separation was achieved using silica gel 60 F254 TLC plates and dichloromethane:methanol:acetone:glacial acetic acid (9:1:0.5:0.3, v/v/v) as a developing system at 230 nm. The second method is based on high-performance liquid chromatography with diode array detection. The proposed compounds are separated on a reversed phase C18 analytical column using phosphate buffer (pH 9; 0.05 M) and methanol (80:20, v/v) at 1.2 mL/min. Linear regressions are obtained in the range of 1-500 μg/mL, 25-1000 μg/mL and 1-400 μg/mL for PAR, Or.cit and CAF, respectively. Quantification of the toxic PAP is carried out using LC-MS-MS by electrospray ionization in the positive mode using triple quadrupole mass spectrometry. The limit of quantification for PAP is 1 ng/mL. All methods are validated according to the ICH guidelines and successfully applied to determine PAR, Or.cit, CAF and PAP in pure powder and in combined tablets dosage form without interference from excipients.

Isolation and Characterization of the Roots of Rumex nervosus

Abstract: 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.

Isolation, identification, and bioactivity of steroids isolates from Hydrilla verticillata petroleum ether fraction

Abstract: Hydrilla verticillata contains some active compounds that potential as an antioxidant, antibacterial, anticancer, antimicrobial and antitumor. One of the active compounds in Hydrilla verticillata is steroids. This research aimed to isolate, to identify and to determine the toxicity and antioxidant activity of steroid compounds in petroleum ether (PE) fraction of Hydrilla verticillata. Hydrilla verticillata biomass powder was extracted by maceration using ethanol solvent. The ethanol extract was hydrolyzed with 2 N of hydrochloric acid and then partitioned with petroleum ether solvent. The steroid compounds from petroleum ether fraction were separated with Preparative Thin Layer Chromatography (TLC) and Column Chromatography. The steroid isolates were identified by UV-Vis and FTIR spectrophotometer. The toxicity level and antioxidant assay of steroid isolates were determined by BSLT and DPPH method, respectively. The result of the study showed that extraction through maceration produced 4.54% yield, whereas the product yield of the partition using petroleum ether was 65.41%. The steroid isolates from TLC and Column Chromatography separation has toxicity and antioxidant properties. The LC50 value of steroid TLC isolate was 1.41 and 12.2 ppm. The LC5o value of steroid Column Chromatography isolates (H2, H4 and H10) were 4.32, 8.24 and 10.35 ppm. The EC50 value of H2 Column Chromatography isolate was 23.00 ppm.

Estimation of the total antioxidant potential in the meat samples using thin-layer chromatography

Abstract: Abstract There is limited literature on the antioxidative properties of food of animal origin. Measurements of antioxidative properties are usually performed using the reaction of reduction of colored 2,2-diphenyl-1-picrylhydrazyl (DPPH) radials. Changes of the DPPH color are tracked photometrically. These measurements are interfered by both, the tested samples and reduced DPPH. This study aims to demonstrate the ability to separate different forms of DPPH (DPPH• and DPPH-H) by thin-layer chromatography (TLC). Further, it has been practically applied in the study of the determination of antioxidative properties of the meat samples. It was found that TLC can be used for the separation of different forms of DPPH as well as for measurement of TAP (total antioxidant potential) values related to the DPPH•. The strongest antioxidant properties were observed for pork neck extracted in buffer pH 2 and for smoked salmon fish extracted in acetone, the lowest for veal and turkey fillet extracted in methanol.

Fractionation of Garcinia Mangostana Fruit Pericarp Cellulase Assisted Extracts by Preparative Thin Layer Chromatography and High Performance Liquid Chromatography

Abstract: 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 IC 50 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 C 18 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.

Evaluation of various biological activities of natural compounds by TLC/HPTLC

Abstract: Over the last years, thin layer chromatography (TLC) has become an increasingly important tool in the analysis of natural compounds, being used not only as a simple method of separation, identifica...