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1,284 result(s) for "TLC"
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Thin-Layer Chromatography (TLC) in the Screening of Botanicals–Its Versatile Potential and Selected Applications
The aim of this paper is to present a comprehensive overview of the main aims and scopes in screening of botanicals, a task of which thin-layer chromatography (TLC) is, on an everyday basis, confronted with and engaged in. Stunning omnipresence of this modest analytical technique (both in its standard format (TLC) and the high-performance one (HPTLC), either hyphenated or not) for many analysts might at a first glance appear chaotic and random, with an auxiliary rather than leading role in research, and not capable of issuing meaningful final statements. Based on these reflections, our purpose is not to present a general review paper on TLC in screening of botanicals, but a blueprint rather (illustrated with a selection of practical examples), which highlights a sovereign and important role of TLC in accomplishing the following analytical tasks: (i) solving puzzles related to chemotaxonomy of plants, (ii) screening a wide spectrum of biological properties of plants, (iii) providing quality control of herbal medicines and alimentary and cosmetic products of biological origin, and (iv) tracing psychoactive plants under forensic surveillance.
Simultaneous, Development and Validation Measurement of Empagliflozin and Linagliptin for Glyxambi® Tablets using TLC and RP-HPLC
This aims of study to develop and validate two chromatographic methods that provide a fast, sensitive, and reliable stability-indicating assay for the simultaneous determination of Empagliflozin and Linagliptin in their pure forms, as well as Glyxambi® tablets. The first technique employed was thin-layer chromatography (TLC) utilizing a developing solution composed of ethyl acetate, methanol, and hexane in a ratio of 90:5:5 (v/v/v). The separation of Empagliflozin and Linagliptin was achieved on silica gel plates, with a scanning wavelength at 248 nm. Retention factor (RF) values for Linagliptin was 0.16 and Empagliflozin was 0.51. Mean percentage recoveries were 101.32% (SD 0.942) for Linagliptin and 99.84% (SD 1.426) for Empagliflozin, the linearity across concentration ranges of 5-50µg/band and 10-150µg/band, respectively. The second technique, known as RP-HPLC, separated the samples using a GL Sciences reverse-phase C18 column (250mm x 4.6mm x 5µm). Water, acetonitrile, and 0.05 M phosphate buffer with a pH of 3.8 (45:50:5, v/v/v) made up the mobile phase, which was used for 10min. We carried out UV detection at 248nm. The chromatogram showed the presence of Linagliptin and Empagliflozin, with retention periods of Rt = 2.242min and 4.065min, respectively. Mean percentage recoveries for Linagliptin were 100.81% (SD 1.631) and for Empagliflozin was 101.44% (SD 1.381), A satisfactory resolution was attained, and linearity was established within the range of 0.5-10 and 2-35 µg/ml, respectively. We successfully determined Linagliptin and Empagliflozin, whether in bulk powder or combination dose form (Glyxambi® tablets), quantitatively for the pharmaceutical market using the TLC and RP-HPLC techniques.
Indole-3-acetic acid production by Streptomyces fradiae NKZ-259 and its formulation to enhance plant growth
Background Indole-3-acetic acid (IAA) is produced by microorganisms and plants via either tryptophan-dependent or tryptophan-independent pathways. Herein, we investigated the optimisation of IAA production by Streptomyces fradiae NKZ-259 and its formulation as a plant growth promoter to improve economic and agricultural development. Results The maximum IAA yield achieved using optimal conditions was 82.363 μg/mL in the presence of 2 g/L tryptophan after 6 days of incubation. Thin-layer chromatography (TLC) and high-performance liquid chromatography (HPLC) analysis of putative IAA revealed an RF value of 0.69 and a retention time of 11.842 min, comparable with the IAA standard. Regarding product formulation, kaolin-based powder achieved a suspension rate of 73.74% and a wetting time of 80 s. This carrier exhibited good shelf life stability for NKZ-259, and the cell population did not decrease obviously over 4 months of storage at 4 °C. In vivo analysis of plant growth promotion showed that tomato seedlings treated with kaolin powder containing NKZ-259 cells displayed a significant increase in root and shoot length of 7.97 cm and 32.77 cm, respectively, and an increase in fresh weight and dry weight of 6.72 g and 1.34 g. Compared to controls, plant growth parameters were increased almost it two-fold. Conclusion Optimising the culture conditions resulted in an almost four-fold increase in IAA secretion by NKZ-259 cells. The results clearly demonstrate that S. fradiae NKZ-259 holds great potential for plant growth promotion and IAA production. Furthermore, kaolin-based powder is an effective carrier for NKZ-259 cells and may be useful for commercial applications.
Stability of Metronidazole and Its Complexes with Silver(I) Salts under Various Stress Conditions
Metronidazole is a drug widely used in the prevention and treatment of bacterial infections. Due to its possibility of the formation of stable metal complexes, it was decided to broaden its activity spectrum by introducing the silver(I) coordination compounds i.e., [Ag(MTZ)2NO3] and [(Ag(MTZ)2)2]SO4, which have significant antibacterial properties. The paper presents a description of a new qualitative and quantitative analysis of metronidazole in bulk and possible pharmaceutical preparations by thin-layer chromatography with densitometric detection. Optimal separation conditions were selected, and the analytical procedure was validated according to the ICH guidelines. The obtained data indicate that the method is sufficiently sensitive, precise, and accurate. The stability of the metronidazole solutions obtained from tablets, pure metronidazole, and its silver(I) complexes was tested. The research was carried out in various environments, at different temperatures, in H2O2 solution, and during exposure to radiation (UV, sunlight). The greatest degradation was found in the alkaline environment and at higher temperatures. The silver(I) complexes exhibited relatively high stability under analyzed conditions that are higher than standard metronidazole solutions and tablets. The observations were confirmed by the kinetic and thermodynamic analysis. The described studies of new metronidazole silver(I) complexes increase the potential for their application in infections both in humans and animals.
Antimicrobial Potential of Single Metabolites of Curcuma longa Assessed in the Total Extract by Thin-Layer Chromatography-Based Bioautography and Image Analysis
Curcuma longa from Zingiberaceae belongs to the major spices consumed around the world, known from its cholagogue, anti-inflammatory, and antimicrobial properties. Lack of data on the activity of single components of turmeric extract encouraged the authors to apply TLC (thin-layer chromatography) based bioautography studies to reveal its antimicrobial constituents and construct a universal platform for the bioactivity assessment of crude extracts, with help of a freeware ImageJ software. This optimized chromatographic bioassay performed on diethyl ether and methanol extracts of Curcuma longa was successfully applied on the total extract and revealed the antimicrobial potential of single components against a variety of Gram-positive strains, with no need for their isolation from the mixture. The obtained results were further confronted with a classic microdilution antimicrobial assay on the isolates, purified from the crude extracts by centrifugal partition chromatography in the following solvent system: heptane-chloroform-methanol-water (5:6:3:2) (v/v/v/v).
Development and validation of quantitative thin layer chromatographic technique for determination of total aflatoxins in poultry feed and food grains without sample clean-up
The purpose of this work is to develop and validate an appropriate solvent solution and quantitative thin layer chromatography (TLC) method for determining the aflatoxins content of chicken feeds and dietary grains. To obtain the optimal mobile phase, samples were extracted with methanol/water (3:1) + 5% sodium chloride and partitioned using several solvent systems using preparative TLC. Camag TLC scanner 3 was used to scan the TLC plates at 366 nm and quantify them using JustTLC software. The method was tested for linearity, specificity, accuracy, precision, sensitivity, and robustness in accordance with ICH recommendations, and then utilized to screen 132 Nigerian poultry/food samples for total aflatoxins (TAFs). The best separation of aflatoxins was achieved using acetonitrile and dichloromethane (3:17) mobile phase over an average run time of 45 min, resulting in linear calibration curves ( > 0.99) in the concentration range limit of quantitation (LoQ) to 50 ng/spot with a limit of detection of <2.0 ng/g and a LoQ of <4.0 ng/gm for all aflatoxins in all spiked samples. When the proposed TLC method was compared to an optimized high-performance liquid chromatography method, an excellent linear regression was obtained ( > 95%). Seventy seven (58.33%) of the 132 samples examined were positive for aflatoxins, with mean values ranging from 3.57 ± 2.55 to 37.31 ± 34.06 ng/gm for aflatoxin B1 and 6.67 ± 0.00 to 38.02 ± 31.52 ng/gm for TAFs, respectively. The results demonstrate the feasibility of using the suggested TLC method in conjunction with a novel solvent solution (free of carcinogenic chloroform) for the rapid and accurate measurement of TAFs in foods/feeds.
The Potential Use of Herbal Fingerprints by Means of HPLC and TLC for Characterization and Identification of Herbal Extracts and the Distinction of Latvian Native Medicinal Plants
The growing market of herbal medicines, the increase in international trade in Latvia, and the lack of adequate analytical methods have raised the question of the potential use of herbal fingerprinting methods. In this study, high-performance liquid chromatography (HPLC) and thin layer chromatography (TLC) methods were developed for obtaining chromatographic fingerprints of four taxonomically and evolutionary different medicinal plants (Hibiscus sabdariffa L., Calendula officinalis L., Matricaria recutita L., Achillea millefolium L.). Retention time shifting, principal component analysis (PCA), hierarchical cluster analysis (HCA), and orthogonal projections to latent structures (OPLS) analysis were used to improve and analyze the obtained fingerprints. HPLC data detection at 270 nm was determined superior to 360 nm for the distinction of medicinal plants and used data alignment method significantly increased similarity between samples. Analyzed medicinal plant extracts formed separate, compact clusters in PCA, and the results of HCA correlated with the evolutionary relationships of the analyzed medicinal plants. Herbal fingerprinting using chromatographic analysis coupled with multivariate analysis has a great potential for the identification of medicinal plants as well as for the distinction of Latvian native medicinal plants.
TLC in the Analysis of Plant Material
This paper provides an overview of thin-layer chromatography (TLC) and high-performance thin-layer chromatography (HPTLC) methods for analyzing plant materials and herbal formulations, as described in scientific publications from January 2022 to July 2025. It describes the use of TLC in the qualitative and quantitative examination of plant materials and pharmaceutical preparations containing herbs, including profiling plant materials using TLC and applying it to HPTLC plates. It also describes other modern methods that improve component separations, such as applying TLC to profile plant formulations and detect adulterations and contaminants in them. Additionally, it discusses TLC coupled with other methods, such as principal component analysis (PCA), hierarchical cluster analysis (HCA), orthogonal partial least squares discriminant analysis (OPLS-DA), mass spectrometry (MS), nuclear magnetic resonance (NMR), surface-enhanced Raman spectroscopy (SERS), and image analysis (IA). The quantitative determination of biologically active compounds in herbs and herbal formulations is presented based on methods that combine TLC with densitometry. The paper also discusses TLC with effect-oriented analysis, including the detection of antimicrobial, antioxidant, enzyme-inhibiting, endocrine-disrupting, genotoxic, and cytotoxic substances. The advantages, disadvantages, and prospects of analyzing plant material using the TLC technique are indicated. TLC/HPTLC has great prospects for use by regulatory authorities due to the low cost of analysis and high throughput.
Bacillus spp.: potent microfactories of bacterial IAA
Auxin production by bacteria is one of the most important direct mechanisms utilized by plant growth-promoting bacteria (PGPB) for the betterment of plants naturally because auxin is a plant friendly secondary metabolite synthesized naturally by bacteria, and hence improves the growth of associated plants. So, the current study focuses on bacterial synthesis of Indole-3-acetic acid (IAA) for plant growth improvement. In the current study, the PGPB were selected on the basis of their auxin production potential and their growth promoting attributes were evaluated. Indole-3-acetic acid producing potential of two selected bacterial isolates was observed by varying different growth conditions i.e., media composition, carbon sources (glucose, sucrose and lactose) and different concentrations of precursor. Influence of various physiological factors (temperature and incubation time period) on IAA production potential was also evaluated. Both the bacterial strains (So3II) and (Mt3b) showed variable potential for the production of bacterial IAA under different set of growth and environmental conditions. Hence, the IAA production potential of the bacterial isolates can be enhanced by affecting optimum growth conditions for bacterial isolates and can be used for the optimal production of bacterial IAA and its utilization for plant growth improvement can lead to better yield in an eco-friendly manner.
A new colorimetric DPPH• scavenging activity method with no need for a spectrophotometer applied on synthetic and natural antioxidants and medicinal herbs
2,2-Diphenyl-1-picrylhydrazyl (DPPH•) radical scavenging, the most commonly used antioxidant method with more than seventeen thousand articles cited, is very practical; however, as with most assays, it has the major disadvantage of dependence on a spectrophotometer. To overcome this drawback, the colorimetric determination of the antioxidant activity using a scanner and freely available Image J software was developed. In this new method, the mixtures of solutions of DPPH• and standard antioxidants or extracts of common medicinal herbs were dropped onto TLC plates, after an incubation period. The spot images were evaluated with Image J software to determine CSC50 values, the sample concentrations providing 50% colour reduction, which were very similar with the SC50 values obtained with spectrophotometric method. The advantages of the new method are the use of lower amounts of reagents and solvents, no need for costly spectrophotometers, and thus significantly lowered costs, and convenient implementation in any environment and situation.