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1.
J Chromatogr A ; 1732: 465252, 2024 Sep 13.
Article de Anglais | MEDLINE | ID: mdl-39142170

RÉSUMÉ

A new method for efficiently selecting polypotent natural products is proposed in this study. The method involves using effect-directed HPTLC data and multiobjective optimization algorithms to extract chromatographic signals from HPTLC bioassay images. Three different multiobjective optimization methods, namely Derringer's desirability approach, Technique for order of preference by similarity to ideal solution (TOPSIS), and Sum of ranking differences (SRD), were applied to the chromatographic signals. In combination with jackknife cross-validation, Derringer's approach and TOPSIS demonstrated high similarity in finding the best (most polypotent), next to the best, next to the worst, and worst (least polypotent) extracts, while the SRD resulted in slightly different outcomes. Furthermore, a new method for identifying the chromatographic features that characterize the most polypotent extracts was proposed. This method is based on partial least square regression (PLS) and can be used in combination with HPTLC-chemical fingerprints to predict the desirability of new extracts. The resulting PLS models demonstrated high statistical performance with determination coefficients ranging from R2 = 0.885 in the case of Derringer's desirability, to 0.986 for TOPSIS. However, the PLS modeling of SRD values was not successful.


Sujet(s)
Algorithmes , Produits biologiques , Produits biologiques/composition chimique , Produits biologiques/analyse , Chromatographie sur couche mince/méthodes , Méthode des moindres carrés , Chromatographie en phase liquide à haute performance/méthodes , Extraits de plantes/composition chimique
2.
Molecules ; 29(16)2024 Aug 22.
Article de Anglais | MEDLINE | ID: mdl-39203054

RÉSUMÉ

Sulfonamides are not only widely applied in clinics but also highly valued in animal husbandry. Recently, it has become common for sulfonamide residues to exceed the standard limits in food, which can affect human health. Current regulations limit these residues. Therefore, we constructed a new limit test method to rapidly determine the levels of sulfonamide residues. Six sulfonamides were detected using the latest method called TLC-SERS, namely, sulfamethasone (A), sulfamethazine (B), sulfadoxine (C), sulfamethoxydiazine (D), sulfamethoxazole (E), and sulfathiazole (F). The optimal conditions for SERS detection were investigated for these six drugs, and the separation effects of different TLC spreaders on them were compared. Then, we successfully established a separation system using dichloromethane-methanol-ammonia in a ratio of 5:1:0.25 (v/v/v), which provided good separation effects on the six drugs. The residues were preliminarily separated via TLC. A silver sol solution was added to the spot on the silica gel G plate at the corresponding specific shift values, and SERS detection was performed. The sample solution was placed on the spot under a 532 nm laser, and the SERS spectrum was collected and analyzed for the six sulfonamides. The results showed obvious variations in the SERS spectrum among the six sulfonamides, with the LODs being 12.5, 6.4, 6.3, 7.1, 18.8, and 6.2 ng/mL from A to F, respectively, and an RSD of <3.0%. Within 48 h, the SERS signal for each sulfonamide drug was kept stable, with an RSD of <3.0%. The detection results of 20 samples using the TLC-SERS method were consistent with those obtained by UPLC-MS/MS. The established TLC-SERS method is simple and fast, providing a useful reference for the rapid detection of residue limits in food.


Sujet(s)
Analyse spectrale Raman , Sulfonamides , Sulfonamides/analyse , Chromatographie sur couche mince/méthodes , Analyse spectrale Raman/méthodes , Contamination des aliments/analyse , Analyse d'aliment/méthodes , Résidus de médicaments/analyse , Limite de détection , Animaux
3.
J Vis Exp ; (209)2024 Jul 26.
Article de Anglais | MEDLINE | ID: mdl-39141547

RÉSUMÉ

Thin layer chromatography-direct bioautography (TLC-DB) is a well-established bioassay used to separate and identify natural products (NPs) that are antagonistic against a target pathogen. It is a rapid, inexpensive, and simple option for the bioassay-guided isolation and identification of NPs that hinges on separation by TLC coupled with the direct application of a target pathogen to examine bioactivity. It is typically used for the analysis of bioactive plant extracts, detecting inhibitory activity against bacteria, fungi, and enzymes. That being said, it has great potential in bacterial NP discovery, particularly for evaluating bacterial NPs against pertinent agricultural pathogens, which is valuable for discovering and developing novel biopesticides for the agriculture industry. Furthermore, it is a tunable protocol that could be applied to other target pathogens or sources of NPs in research programs concerning the discovery and identification of bioactive compounds. Herein, we describe a model system for discovering and identifying biopesticide NPs using TLC-DB with Bacillus spp. and the agricultural pathogen Sclerotinia sclerotiorum.


Sujet(s)
Ascomycota , Dosage biologique , Produits biologiques , Chromatographie sur couche mince/méthodes , Produits biologiques/pharmacologie , Produits biologiques/composition chimique , Ascomycota/composition chimique , Dosage biologique/méthodes , Bacillus/composition chimique , Agents de lutte biologique/pharmacologie , Agents de lutte biologique/composition chimique
4.
Anal Methods ; 16(32): 5584-5590, 2024 Aug 15.
Article de Anglais | MEDLINE | ID: mdl-39093047

RÉSUMÉ

Ficus hirta Vahl is a healthy food with both medicinal and culinary properties and with anti-inflammatory and anti-aging effects. There is currently no standardized or universally accepted research strategy for evaluating the quality of Ficus hirta Vahl granules (FHGs). Therefore, the development of a comprehensive quality evaluation method is crucial for the quality control of FHGs. In this study, we used n-hexane : trichloromethane : ethyl acetate : glacial acetic acid = 20 : 4 : 7 : 1 as the optimal developing agent for TLC to separate and identify 15 batches of FHGs from different origins. Using HPLC, a fingerprint with 7 common peaks was established, and peaks 6 and 7 were attributed to psoralen and bergapten, respectively. The content of the identified components was determined. Further quality evaluation of FHGs was performed using chemical pattern recognition, and the results showed that hierarchical cluster analysis (HCA) could cluster 15 batches of FHGs into 2 categories. Principal component analysis (PCA) showed that 2 principal components can show the similarities and differences between different batches of FHGs. Orthogonal partial least squares discrimination (OPLS-DA) showed that components 5, 6 (psoralen) and 7 (bergapten) are landmark components that cause differences in FHG quality from different regions. By integrating the analytical modes of TLC, HPLC fingerprint and chemical pattern recognition, a scientific basis is provided for the comprehensive control and evaluation of herbal medicine quality.


Sujet(s)
Ficus , Contrôle de qualité , Ficus/composition chimique , Chromatographie en phase liquide à haute performance/méthodes , Chromatographie sur couche mince/méthodes , Analyse en composantes principales , Analyse de regroupements , Médicaments issus de plantes chinoises/composition chimique , Médicaments issus de plantes chinoises/analyse , Médicaments issus de plantes chinoises/normes
5.
Food Chem ; 460(Pt 2): 140583, 2024 Dec 01.
Article de Anglais | MEDLINE | ID: mdl-39089026

RÉSUMÉ

Thin-layer chromatography (TLC) hyphenated to bioassays is a modern tool used for discovery of biologically active compounds from complex mixtures. The first bioautographic assay for detecting laccase inhibitors on a TLC plate was developed in this study. The on-plate reaction of laccase with colourless ABTS that renders the blue ABTS∙+ radical was optimised. Combination of the enzymatic TLC-assay with a control TLC-assay, wherein ABTS∙+ radical is chemically generated and then applied on the TLC, allowed to differentiate between the pure laccase inhibitor sodium azide and radical scavengers such as gallic and kojic acids. The limit of detection and quantification for the method were 54.9 and 166 ng of sodium azide respectively. The methodology was applied successfully to a recently discovered laccase inhibitor chemotype: hydrazones. A model hydrazone was compared with several hydrazones synthesized for this study. For the first time, laccase inhibitors separated on a TLC plate can be detected individually.


Sujet(s)
Antienzymes , Laccase , Laccase/antagonistes et inhibiteurs , Laccase/composition chimique , Chromatographie sur couche mince , Antienzymes/composition chimique , Antienzymes/pharmacologie , Protéines fongiques/composition chimique , Protéines fongiques/antagonistes et inhibiteurs , Hydrazones/composition chimique , Hydrazones/pharmacologie
6.
Anal Methods ; 16(28): 4743-4754, 2024 Jul 18.
Article de Anglais | MEDLINE | ID: mdl-38952194

RÉSUMÉ

Various metal ions exist in nature and human beings and play limitless vital roles in both the atmosphere and biology. A fundamental and useful aspect is the qualitative and quantitative assessment of Zn(II) at concentration levels as low as parts per billion (ppb). Thus, the design and development of novel fluorescent turn-on receptors have gained significant interest because of their potential for use in live cell imaging to detect biologically relevant metal ions with high selectivity and sensitivity. The present research illustrates the design and synthesis of a novel fluorescent sensor [(1,3,5-triazine-2,4,6-triyl)tris(hydrazine-2-yl-1-ylidene)tris(methaneylylidene)]tris(2,4-di-tert-butylphenol) (THDBP) for the selective and sensitive probing of Zn(II). The sensor exhibited a fluorescence turn-on mechanism upon treatment with Zn(II) ions at λemi. 503 nm in aq. acetonitrile. The formation of a 1 : 3 complex between THDBP and Zn(II) is confirmed from the Job plot and ESI-MS spectrum. The evaluated limit of detection (LOD) and association constant (Ka) of the sensor THDBP for Zn(II) were found to be 1.03 × 10-10 M and 2.33 × 108 M-1, respectively. Further research demonstrates the practical application of the sensor for the detection of Zn(II) ions in live cells. The sensing ability of the sensor THDBP was also explored through inexpensive test strips and TLC sheets.


Sujet(s)
Colorants fluorescents , Bases de Schiff , Zinc , Zinc/analyse , Zinc/composition chimique , Humains , Colorants fluorescents/composition chimique , Bases de Schiff/composition chimique , Chromatographie sur couche mince/méthodes , Spectrométrie de fluorescence/méthodes , Cellules HeLa , Imagerie optique/méthodes , Limite de détection
7.
Int J Med Mushrooms ; 26(8): 75-83, 2024.
Article de Anglais | MEDLINE | ID: mdl-38967212

RÉSUMÉ

Edible mushrooms, both wild and cultivated, can be seen as healthy functional food. More and more valuable compounds are obtained from mycelia of macromycetes. However, there was limited report about the medicinal fungus Laetiporus versisporus (Lloyd) Imazeki. Herein, L. versisporus was fermented on rice media and the secondary metabolites of mycelia were investigated. In this study, two-step method was used to obtain fermented products, silica gel column chromatography, recrystallization, medium pressure column chromatography, preparative thin-layer chromatography were applied to separate the chemical constituents. Nine chemical compounds (1-9) including one new triterpenoid acid versisponic acid F were identified by NMR (nuclear magnetic resonance) spectroscopy and MS (mass spectrometry). Seven compounds including monolinoleoyl glycerol, linoleic acid, ergosta-5, 7, 22-triene-3ß-ol, ß-sitosterol, daucosterol, versisponic acid F were isolated for the first time from L. versisporus.


Sujet(s)
Fermentation , Mycelium , Mycelium/composition chimique , Spectroscopie par résonance magnétique , Triterpènes/composition chimique , Chromatographie sur couche mince , Spectrométrie de masse , Acide linoléique/métabolisme , Structure moléculaire , Agaricales/composition chimique , Agaricales/métabolisme , Oryza/composition chimique , Sitostérol/composition chimique , Sitostérol/isolement et purification
8.
BMC Complement Med Ther ; 24(1): 279, 2024 Jul 23.
Article de Anglais | MEDLINE | ID: mdl-39044256

RÉSUMÉ

BACKGROUND: The wound healing process, restoring the functionality of the damaged tissue, can be accelerated by various compounds. The recent experimental analysis highlights the beneficial effects of phytochemicals in improving skin regeneration and wound healing. In traditional medicine, one of the widespread plants used for treating different injuries or skin afflictions is Galium aparine L. (GA). Besides, previously reported chemical compounds of GA suggested its therapeutic effects for the wound healing process, yet its regulatory effects on the cellular and molecular stages of the wound healing process have not been investigated. METHODS: In the present study, the phytochemical profile of the GA extract was analyzed using HPTLC fingerprinting, and further scientific evaluation of its phytochemicals was done. The wound-healing effects of GA extract were explored at the cellular and molecular levels while accounting for cell toxicity. The wound closure enhancing effect, antibacterial activity, and antioxidant activity were assessed. RESULTS: The HPTLC fingerprinting of the GA extract proved its previously reported phytochemical profile including phenols, flavonoids, tannins, plant acids, ergot alkaloids, flavonoids, anthraquinones, terpenoids, sterols, salicin, lipophilic compounds, saponins, iridoids, and heterocyclic nitrogen compounds. Antimicrobial assessment, of the extract, indicated the more susceptibility of S. aureus to the inhibitory effects of GA rather than E. coli and S. epidermidis. DPPH test results revealed the antioxidant property of GA extract, which was comparable to ascorbic acid. The results of the viability assay showed no cytotoxicity effects on human umbilical endothelial cell (HUVEC) and normal human dermal fibroblast (NHDF) cell lines treated with different concentrations of whole plant extract and cell viability increased in a dose-dependent manner. The results of the scratch assay showed improved cell migration and wound closure. CONCLUSIONS: This study shows the anti-oxidant, anti-microbial, and in vitro wound healing wound-healing effects of GA hydroalcoholic extract, which aligns with its use in traditional medicine. No cytotoxicity effects were shown. The results from this study can be the basis for further investigations such as animal models and phytochemical studies. Further evaluation of its effects on mechanisms and signaling pathways involved in the wound healing processes such as angiogenesis and cell proliferation can provide novel insights into the potential therapeutic effects of the GA extract.


Sujet(s)
Antioxydants , Extraits de plantes , Cicatrisation de plaie , Cicatrisation de plaie/effets des médicaments et des substances chimiques , Antioxydants/pharmacologie , Extraits de plantes/pharmacologie , Extraits de plantes/composition chimique , Humains , Composés phytochimiques/pharmacologie , Chromatographie sur couche mince , Antibactériens/pharmacologie , Anti-infectieux/pharmacologie , Médecine traditionnelle
9.
Chemosphere ; 363: 142919, 2024 Sep.
Article de Anglais | MEDLINE | ID: mdl-39059639

RÉSUMÉ

The main aim of this study is to experimentally investigate the yield of extraction and the presence of wax in the extracted yield from Musaacuminata (banana) biomass based on various functional groups that are present in natural wax. Extraction of natural wax from Musaacuminata (banana) biomass has been done by using the Soxhlet apparatus method in the presence of both polar (ethyl acetate and ethanol) and non-polar (toluene and hexane) solvents. The extracted yield has been found as 3.58% from hexane, 5.16% from toluene, 7.03% from ethyl acetate, and 10.26% from ethanol. The wax was also found in the extracted yield only in the case of nonpolar solvents (toluene and hexane). The novelty of this work is that Musaacuminata (banana) waste biomass has been utilized to recover the natural wax using nonpolar solvents and also compared with that of polar solvents to check the scope of wax extraction using polar solvents. Also, statistical analysis has been performed of the extracted yield using both solvents. Thin Layer Chromatography (TLC) and Fourier Transform Infrared Spectroscopy (FTIR) methods have been used to determine the various hydrocarbon chains present in the extracted yield which is similar to that of natural wax.


Sujet(s)
Biomasse , Musa , Solvants , Cires , Cires/composition chimique , Solvants/composition chimique , Musa/composition chimique , Spectroscopie infrarouge à transformée de Fourier , Chromatographie sur couche mince , Hexanes/composition chimique , Éthanol/composition chimique , Toluène/composition chimique , Toluène/analyse , Acétates/composition chimique
10.
World J Microbiol Biotechnol ; 40(9): 278, 2024 Jul 24.
Article de Anglais | MEDLINE | ID: mdl-39046545

RÉSUMÉ

This study investigates the synthesis of vinblastine by endophytic fungi isolated from leaf of C. roseus. A total of 10 endophytic fungi were selected for secretion of vinca alkaloids based on the initial screening by biochemical tests and thin-layer chromatography (TLC). Out of these ten, only four fungal extracts showed positive results for presence of vinblastine at same retention time (10 min.) compared to reference compound on HPLC analysis. The detected concentration of vinblastine was maximum (17 µg/ml) in isolate no. CRL 22 followed by CRL 52, CRL 17 and CRL 28. To validate the presence of vinblastine, ultra-high-performance liquid chromatography coupled with high-resolution accurate mass spectrometry (HRMS) was employed. This analysis confirmed the presence of anhydrovinblastine, a precursor of vinblastine through the detection of molecular ions at m/z 793.4185 in extract of CRL 17. In addition to anhydrovinblastine, the intermediate compounds essential to the biosynthetic pathway of vinblastine were also detected in the extract of CRL 17. These host-origin compounds strongly suggest the presence of a biosynthetic pathway within the endophytic fungus. Based on morphological observation and sequence analysis of the ITS region of rDNA, endophytic fungi were identified as Alternaria alternata (CRL 17), Curvularia lunata (CRL 28), Aspergillus terrus (CRL 52), and Aspergillus clavatonanicus (CRL 22).


Sujet(s)
Catharanthus , Endophytes , Champignons , Feuilles de plante , Vinblastine , Catharanthus/microbiologie , Vinblastine/métabolisme , Endophytes/métabolisme , Endophytes/isolement et purification , Chromatographie en phase liquide à haute performance , Champignons/métabolisme , Champignons/isolement et purification , Champignons/classification , Champignons/génétique , Feuilles de plante/microbiologie , Chromatographie sur couche mince , Voies de biosynthèse , Spectrométrie de masse
11.
J Chromatogr A ; 1730: 465090, 2024 Aug 16.
Article de Anglais | MEDLINE | ID: mdl-38955129

RÉSUMÉ

A new, versatile, and straightforward vapor phase deposition (VPD) approach was used to prepare continuous stationary phase gradients (cSPGs) on silica thin-layer chromatography (TLC) plates using phenyldimethylchlorosilane (PDCS) as a precursor. A mixture of paraffin oil and PDCS was placed at the bottom of an open-ended rectangular chamber, allowing the reactive silanes to evaporate and freely diffuse under a controlled atmosphere. As the volatile silane diffused across the length of the TLC plate, it reacted with the surface silanol groups thus functionalizing the surface in a gradient fashion. Characterization of the gradient TLC plates was done through UV visualization and diffuse reflectance spectroscopy (DRS). Visualizing the fluorescent gradient plates under UV radiation shows the clear presence of a gradient with the side closest to the vapor source undergoing the most modification. More quantitative characterization of the shape of the gradient was provided by DRS. The DRS showed that the degree of modification and shape of the gradient was dependent on the concentration of silane, VPD time, and relative humidity. To evaluate the chromatographic performance, a mixture of three aromatic compounds (acetaminophen (A), aspirin (As), and 3-hydroxy-2-naphthoic acid (3H)) was spotted on the high (GHP) and low phenyl (GLP) ends of the gradient TLC plates and the results compared to the separations carried out on unmodified and uniformly modified plates. The GHP TLC plates showed retention factors (Rf) of 0.060 ± 0.006, 0.391 ± 0.006, and 0.544 ± 0.006, whereas the unmodified plate displayed Rf values of 0.059 ± 0.006, 0.092 ± 0.003, and 0.037 ± 0.002 for the analytes A, As, and 3H, respectively. From the Rf values, it was observed that each modified plate exhibited different selectivity for the analytes. The GHP TLC plates exhibited better separation performance, and improved resolution compared to the GLP, unmodified, and uniformly modified plates. Overall, VPD is a new, cost-effective method for creating a gradient on the stationary phase which has the potential to advance chromatographic separation capabilities.


Sujet(s)
Silanes , Chromatographie sur couche mince/méthodes , Silanes/composition chimique , Acétaminophène/composition chimique , Acétaminophène/analyse , Acide acétylsalicylique/composition chimique , Acide acétylsalicylique/analyse , Silice/composition chimique
12.
Molecules ; 29(13)2024 Jun 21.
Article de Anglais | MEDLINE | ID: mdl-38998918

RÉSUMÉ

The Brassicaceae family, commonly referred to as cruciferous plants, is globally cultivated and consumed, with the Brassica genus being particularly renowned for its functional components. These vegetables are rich sources of nutrients and health-promoting phytochemicals, garnering increased attention in recent years. This study presents a comprehensive microscopic, chromatographic, and spectroscopic characterization of Brassica napus L. seeds from Kazakhstan aimed at elucidating their morphological features and chemical composition. Microscopic analysis revealed distinct localization of flavonoids, total lipids, and alkaloids. High-performance thin-layer chromatography (HPTLC) analysis of seed extracts demonstrated a complex chemical profile with significant quantities of non-polar compounds in the hexane extracts. Additionally, methanolic extracts revealed the presence of diverse chemical compounds, including alkaloids, flavonoids, and glucosinolates. The chemical composition exhibited varietal differences across different Brassica species, with B. napus L. seeds showing higher concentrations of bioactive compounds. Furthermore, liquid chromatography-quadrupole time-of-flight mass spectrometry (LC-QToF-MS) analysis provided insights into the chemical composition, with sinapine isomers, feruloyl, and sinapoyl choline derivatives as major compounds in the seeds. This study contributes to a better understanding of the chemical diversity and quality control methods' approximations of B. napus L. seeds, highlighting their importance in functional food and nutraceutical applications.


Sujet(s)
Brassica napus , Graines , Brassica napus/composition chimique , Graines/composition chimique , Extraits de plantes/composition chimique , Extraits de plantes/analyse , Composés phytochimiques/analyse , Composés phytochimiques/composition chimique , Chromatographie sur couche mince/méthodes , Chromatographie en phase liquide à haute performance/méthodes , Flavonoïdes/analyse , Flavonoïdes/composition chimique , Alcaloïdes/analyse , Alcaloïdes/composition chimique , Chromatographie en phase liquide/méthodes , Spectrométrie de masse/méthodes , Glucosinolates/analyse , Glucosinolates/composition chimique
13.
J Sep Sci ; 47(12): e2400099, 2024 Jun.
Article de Anglais | MEDLINE | ID: mdl-38937914

RÉSUMÉ

The chromatographic behavior of the selected compounds was studied under conditions of hydrophilic interaction liquid chromatography (HILIC). The effect of mobile phase composition on the retention in different chromatographic systems was systematically examined using high-performance thin-layer chromatography. The sorbents of different polarity and adsorption characteristics were selected and mixtures of water and organic solvents of various compositions, from pure water to pure organic solvent were used as mobile phases. Increasing the amount of water in the mobile phase leads to a conversion of the separation mechanism, and the retention curves have a characteristic "U" shape. The conversion between the adsorption and partition mechanisms is most likely continuous and depends on the chemical nature of separated substances, the stationary phase as well as on organic component of the mobile phase. Silica gel can be considered the most suitable stationary phase for the systematic investigation of the chromatographic behavior of the test compounds, whereas acetonitrile was the most suitable solvent. The obtained results contribute to the understanding of the dominant separation mechanism, the type, and the intensity of the interactions between separated substances with both stationary and mobile phases. Besides, the lipophilicity parameters obtained under HILIC conditions were evaluated and correlated with the calculated values.


Sujet(s)
Interactions hydrophobes et hydrophiles , Chromatographie sur couche mince , Solvants/composition chimique , Adsorption , Chromatographie en phase liquide
14.
Sud Med Ekspert ; 67(3): 39-44, 2024.
Article de Russe | MEDLINE | ID: mdl-38887070

RÉSUMÉ

The aim of the work is to study the nature of the distribution of 2-A-4.6-DNP in the organisms of warm-blooded animals with intragastric administration of a toxicant. The study was carried out using the methods of TLC, UV-Visible spectroscopy, and GC-MS using derivatives of 2-A-4.6-DNP. Male Wistar rats at the age of 4 months were considered as a model of the body of a warm-blooded animal. An oily suspension of 2-A-4.6-DNF was administered intragastrically in an amount of three times the LD50. Extraction of the target substance from the biomaterial was carried out by double infusion (30 minutes each) with a mixture of acetone-acetonitrile (1:1), the amount of the mixture exceeded the weight of the biomaterial by 2 times. Extractions were purified by TLC method using «Sorbfil¼ plates and acetone-chloroform (7: 3) mobile phase. Preliminary identification was carried out at the same time using a standard substance. Confirmatory identification was carried out by the absorption of dimethylformamide eluates in «SF-2000¼, as well as by the retention time and mass spectra of the major compound of the corresponding chromatographic peaks after GC-MS analysis. The quantitative content was determined spectrophotometrically, in DMF, by optical density at the analytical wavelength (490 nm). 2-Amino-4.6-dinitrophenol was found unchanged in the blood and in all the studied hollow and parenchymal organs of poisoned rats. The largest amount of 2-amino-4.6-dinitrophenol (mg/100 g) was found in the stomach walls (199.39±25.43) and stomach contents (143.14±22.63), a significant amount of the substance was found in the heart (33.49±3.66), skeletal muscles (30.70±2.64), as well as in the spleen (24.30±1.96).


Sujet(s)
Toxicologie médicolégale , Chromatographie gazeuse-spectrométrie de masse , Rat Wistar , Animaux , Rats , Toxicologie médicolégale/méthodes , Mâle , Chromatographie gazeuse-spectrométrie de masse/méthodes , Chromatographie sur couche mince/méthodes , Distribution tissulaire
15.
Molecules ; 29(11)2024 May 24.
Article de Anglais | MEDLINE | ID: mdl-38893351

RÉSUMÉ

The 5-heterocyclic 2-(2,4-dihydroxyphenyl)-1,3,4-thiadiazoles were obtained as potential biologically active compounds. Lipophilicity is one of the most important physicochemical properties of compounds and was already taken into account during the drug candidates design and development. The lipophilicity of compounds was determined using the computational (log P) and chromatography (log kw, RMw) methods. The experimental ones included the reverse-phase column high performance liquid chromatography RP (HPLC) with C8, C18, phosphatidylcholine (IAM), and cholesterol stationary phases and the thin layer chromatography (RP-HPTLC) with C8 and C18 stationary phases and various organic modifiers under the isocratic conditions. Descriptive statistics, correlation, and PCA analyses were used to compare the obtained results. For lipophilicity estimation of the tested compounds by HPTLC, dioxane and MeOH seem to be particularly beneficial as organic modifiers. The chromatographic lipophilicity parameters log kw (RMw) were well correlated and highly redundant (85%) compared with those calculated. Most compounds possess lipophilicity parameters within the recommended range for drug candidates.


Sujet(s)
Interactions hydrophobes et hydrophiles , Thiadiazoles , Thiadiazoles/composition chimique , Chromatographie en phase liquide à haute performance/méthodes , Chromatographie sur couche mince/méthodes , Simulation numérique , Chromatographie en phase inverse/méthodes
16.
Acta Chim Slov ; 71(2): 226-235, 2024 Apr 17.
Article de Anglais | MEDLINE | ID: mdl-38919103

RÉSUMÉ

A Quantitative structure-retention relationship (QSRR) analysis has been carried out on the chromatography parameters of lipophilicity of selected spirohydantoins. Multiple linear regression (MLR) was applied for construct the QSRR models. The chromatographic parameters of lipophilicity were determined by reversed-phase thin-layer chromatography. Chromatographic analyses were performed on C-18 modified silica gel with a two-component mobile phase consisting of water and protic organic solvent (ethanol, n-propanol, i-propanol, or t-butanol) in different ratios. QSRR models were built and for additional four aqueous mobile phases: acetone-water, acetonitrile-water, tetrahydrofuran-water, and 1,4-dioxane-water (results published before). In total, chromatographic lipophilicity parameters obtained for two types of organic solvents was subject of the QSRR. The predictive ability of each model was defined by an internal validation coefficient. The best QSRR model for predicting the chromatographic parameter of lipophilicity was obtained for tetrahydrofuran as an organic solvent.


Sujet(s)
Hydantoïnes , Chromatographie sur couche mince , Hydantoïnes/composition chimique , Relation quantitative structure-activité , Spiranes/composition chimique , Solvants/composition chimique , Modèles linéaires , Dioxanes
17.
World J Microbiol Biotechnol ; 40(8): 253, 2024 Jun 25.
Article de Anglais | MEDLINE | ID: mdl-38914906

RÉSUMÉ

Liamocins, a group of high-density glycolipids, are only produced by certain strains of the yeast-like fungi in the genus Aureobasidium. Until now, few studies have focused on the surfactant properties of liamocins produced from the highly diverse tropical strains of Aureobasidium. Therefore, the aims of this research were to screen the liamocin production from tropical strains of Aureobasidium spp. and to characterize their surfactant properties. A total of 41 strains of Thai Aureobasidium spp. were screened for their ability to produce liamocins, and the products were detected using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry and thin-layer chromatography. Of those strains, 30 strains of Aureobasidium spp. tested were found to produce liamocins with yields ranging from 0.53 to 10.60 g/l. The nature of all crude liamocins was heterogeneous, with different compositions and ratios depending on the yeast strain. These liamocins exhibited relatively high emulsifying activity against vegetable oils tested, with an emulsification index of around 40-50%; the emulsion stability of some liamocins was up to 30 days. The obtained critical micelle concentration values were varied, with those ​​of liamocins produced from A. pullulans, A. melanogenum and A. thailandense falling in ranges from 7.70 to 119.78, 10.73 to > 1,000, and 68.56 to > 1,000 mg/l, respectively. The emulsification activity of liamocins was higher than that of the analytical grade rhamnolipids. These compounds showed strong surface tension reduction in a sodium chloride concentration range of 2-12% (w/v), pH values between 3 and 7, and temperatures between 4 and 121 °C. This is the first report of liamocins produced by A. thailandense.


Sujet(s)
Aureobasidium (genre) , Glycolipides , Glycolipides/métabolisme , Glycolipides/biosynthèse , Glycolipides/composition chimique , Aureobasidium (genre)/métabolisme , Tensioactifs/métabolisme , Tensioactifs/pharmacologie , Tensioactifs/composition chimique , Thaïlande , Chromatographie sur couche mince , Huiles végétales/métabolisme , Spectrométrie de masse MALDI , Émulsifiants/métabolisme , Émulsifiants/composition chimique , Émulsions
18.
Article de Anglais | MEDLINE | ID: mdl-38824745

RÉSUMÉ

A novel and highly sensitive high-performance thin-layer chromatographic (HPTLC) method was developed and validated to quantify a combination of five pharmaceutical mixtures spiked to human plasma. The compounds comprised Amlodipine (AML) along with five angiotensin II receptor antagonist drugs (AIIRAs), namely Olmesartan (OLM), Telmisartan (TLM), Candesartan (CAN), Losartan (LOS), and Irbesartan (IRB). HPTLC was performed on silica gel 60 F254 plates using a mobile phase of Toluene: ethyl acetate: methanol: acetone: acetic acid (6:1.5:1:0.5:1, v/v/v/v/v). In a pioneering move, a reflectance/fluorescence detection mode was employed to identify two concurrently administered drugs at different pH levels for the first time. This method utilized the same chromatographic system, incorporating a specific measurement for AML at a neutral medium to achieve its maximum fluorescence at a 360 nm excitation wavelength, and measuring emission using a 540 nm optical filter. The process involved obtaining a very low fluorescence response from AIIRA. Subsequently, to enhance AIIRA's fluorescence, the plate was sprayed with perchloric acid to transition to a strong acidic medium, ultimately attaining the maximum fluorescence of AIIRA using various excitation wavelengths and a 400 nm emission filter. Through this strategic process, we could optimize the fluorescence signals of both drugs, thereby elevating the sensitivity of detection for this drug combination. AML demonstrated a linear range of 18-300 ng/band, while AIIRAs drugs exhibited a linear range of 6-150 ng/band. The method satisfied the International Conference on Harmonization (ICH) criteria for recovery, precision, repeatability, and robustness, showcasing exceptional sensitivity. The approach was successfully applied to quantify AML and AIIRAs drugs in both bulk drug and plasma samples, achieving high recovery percentages and minimal standard deviations.


Sujet(s)
Amlodipine , Densitométrie , Limite de détection , Amlodipine/sang , Humains , Chromatographie sur couche mince/méthodes , Concentration en ions d'hydrogène , Reproductibilité des résultats , Densitométrie/méthodes , Modèles linéaires , Antagonistes des récepteurs aux angiotensines/sang , Spectrométrie de fluorescence/méthodes
19.
Microb Pathog ; 192: 106702, 2024 Jul.
Article de Anglais | MEDLINE | ID: mdl-38825090

RÉSUMÉ

The soil bacterium DP1B was isolated from a marine sediment collected off the coast of Randayan Island, Kalimantan Barat, Indonesia and identified based on 16S rDNA as Nocardiopsis alba. The bacterium was cultivated in seven different media (A1, ISP1, ISP2, ISP4, PDB, PC-1, and SCB) with three different solvents [distilled water, 5 % NaCl solution, artificial seawater (ASW)] combinations, shaken at 200 rpm, 30 °C, for 7 days. The culture broths were extracted with ethyl acetate and each extract was tested for its antimicrobial activity and brine shrimp lethality, and the chemical diversity was assessed using thin-layer chromatography (TLC), gas chromatography (GC), and liquid chromatography-mass spectrometry/mass spectrometry (LC-MS/MS). The result showed that almost all extracts showed antibacterial but not antifungal activity, whereas their brine shrimp toxicity levels vary from high to low. The best medium/solvent combinations for antibacterial activity and toxicity were PC-1 (in either distilled water, 5% NaCl solution, or ASW) and SCB in ASW. Different chemical diversity profiles were observed on TLC, GC-MS, and LC-MS/MS. Extracts from the PC-1 cultures seem to contain a significant number of cyclic dipeptides, whereas those from the SCB cultures contain sesquiterpenes, indicating that media and solvent compositions can affect the secondary metabolite profiles of DP1B. In addition, untargeted metabolomic analyses using LC-MS/MS showed many molecular ions that did not match with those in the Global Natural Products Social Molecular Networking (GNPS) database, suggesting that DP1B has great potential as a source of new natural products.


Sujet(s)
Antibactériens , Artemia , Sédiments géologiques , ARN ribosomique 16S , Animaux , Artemia/effets des médicaments et des substances chimiques , Sédiments géologiques/microbiologie , ARN ribosomique 16S/génétique , Antibactériens/pharmacologie , Chromatographie en phase liquide , Métabolomique , Milieux de culture/composition chimique , Indonésie , Spectrométrie de masse en tandem , Actinobacteria/métabolisme , Actinobacteria/composition chimique , Actinobacteria/génétique , Actinobacteria/classification , Tests de sensibilité microbienne , Eau de mer/microbiologie , Chromatographie gazeuse-spectrométrie de masse , Métabolome , Chromatographie sur couche mince , Phylogenèse , Antifongiques/pharmacologie , Antifongiques/métabolisme , Antifongiques/isolement et purification , Antifongiques/composition chimique
20.
ScientificWorldJournal ; 2024: 8128813, 2024.
Article de Anglais | MEDLINE | ID: mdl-38827814

RÉSUMÉ

The genus Hypericum comprises a large number of species. The flower, leaf, stem, and root of the Hypericum species are widely used in traditional medicine in different cultures. Many Hypericum species have been well investigated phytochemically and pharmacologically. However, only a few reports are available on the H. cordifolium native to Nepal. The present study aims to evaluate the phytochemical composition of different extracts, qualitative analysis of methanol extract of the flower and leaf using thin-layer chromatography (TLC), and the antioxidant properties of components by the TLC-DPPH. assay. The phenolic and flavonoid contents were estimated in different extracts of the leaf and stem, and their antioxidant and antibacterial activities were evaluated. In the phytochemical screening, phenolics and flavonoids were present in ethyl acetate, methanol, and 50% aq methanol extracts of both the leaf and stem. In TLC analysis, the methanol extract of flowers showed the presence of 11 compounds and the leaf extract showed the presence of 8 compounds. Both extracts contained chlorogenic acid and mangiferin. Hyperoside and quercetin were present only in the flower extract. In the TLC-DPPH. assay, almost all of the flower extracts and 5 compounds of the leaf extract showed radical scavenging potential. Estimation of phenolics and flavonoids showed that all the leaf extracts showed higher amounts of phenolics and flavonoids than stem extracts. Among leaf extracts, greater amounts of phenolics were detected in 50% aqueous methanol extract (261.25 ± 1.66 GAE/g extract) and greater amounts of flavonoids were detected in methanol extract (232.60 ± 10.52 CE/g extract). Among stem extracts, greater amounts of flavonoids were detected in the methanol extract (155.12 ± 4.30 CE/g extract). In the DPPH radical scavenging assay, the methanol extract of the leaf showed IC50 60.85 ± 2.67 µg/ml and 50% aq. methanol extract of the leaf showed IC50 63.09 ± 2.98 µg/ml. The methanol extract of the stem showed IC50 89.39 ± 3.23 µg/ml, whereas ethyl acetate and 50% aq. methanol extract showed IC50 > 100 µg/ml. In the antibacterial assay, the methanol extract of the leaf showed the inhibition zone of 12-13 mm and the stem extract showed the inhibition zone of 7-11 mm against S. aureus, E. coli, and S. sonnei, whereas both extracts were inactive against S. typhi. The findings of this study support the traditional use of this plant in Nepal for the treatment of diseases associated with bacterial infections. The present study revealed that the underutilized anatomical parts of H. cordifolium could be the source of various bioactive phytochemicals like other Hypericum species.


Sujet(s)
Antibactériens , Antioxydants , Flavonoïdes , Hypericum , Composés phytochimiques , Extraits de plantes , Hypericum/composition chimique , Antibactériens/pharmacologie , Antibactériens/composition chimique , Antibactériens/analyse , Antioxydants/pharmacologie , Antioxydants/composition chimique , Antioxydants/analyse , Extraits de plantes/pharmacologie , Extraits de plantes/composition chimique , Composés phytochimiques/composition chimique , Composés phytochimiques/analyse , Composés phytochimiques/pharmacologie , Flavonoïdes/analyse , Flavonoïdes/composition chimique , Feuilles de plante/composition chimique , Phénols/analyse , Phénols/composition chimique , Tests de sensibilité microbienne , Chromatographie sur couche mince , Tiges de plante/composition chimique
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