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1.
Molecules ; 28(23)2023 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-38067527

RESUMO

Fenugreek (Trigonella foenum-graecum) has a great beneficial health effect; it has been used in traditional medicine by many cultures. Likewise, the α-amylase inhibitors are potential compounds in the development of drugs for the treatment of diabetes. The beneficial health effects of fenugreek lead us to explore the chemical composition of the seeds and their antioxidant and α-amylase inhibition activities. The flavonoid extraction from fenugreek seeds was achieved with methanol through a Soxhlet apparatus. Then, the flavonoid glycosides were characterized using HPLC-DAD-ESI-MS analysis. The antioxidant capacity of fenugreek seed was measured using DPPH, FRAP, ABTS, and CUPRAC assays. Finally, the α-amylase inhibition activity was carried out using in vitro and in silico methods. The methanolic extract was found to contain high amounts of total phenolics (154.68 ± 1.50 µg GAE/mg E), flavonoids (37.69 ± 0.73 µg QE/mg E). The highest radical-scavenging ability was recorded for the methanolic extract against DPPH (IC50 = 556.6 ± 9.87 µg/mL), ABTS (IC50 = 593.62 ± 9.35 µg/mL). The ME had the best reducing power according to the CUPRAC (A 0.5 = 451.90 ± 9.07 µg/mL). The results indicate that the methanolic extracts of fenugreek seed best α-amylase inhibition activities IC50 = 653.52 ± 3.24 µg/mL. Twenty-seven flavonoids were detected, and all studied flavonoids selected have good affinity and stabilize very well in the pocket of α-amylase. The interactions between the studied flavonoids with α-amylase were investigated. The flavonoids from fenugreek seed present a good inhibitory effect against α-amylase, which is beneficial for the prevention of diabetes and its complications.


Assuntos
Diabetes Mellitus , Trigonella , Humanos , Antioxidantes/química , Trigonella/química , Flavonoides/farmacologia , Flavonoides/análise , Simulação de Acoplamento Molecular , alfa-Amilases , Cromatografia Líquida de Alta Pressão , Extratos Vegetais/química , Metanol/química , Sementes/química
2.
Materials (Basel) ; 16(24)2023 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-38138818

RESUMO

Sludge, due to its form and significant moisture and zinc content, is the most problematic metallurgical waste. Near the site of a disused steelworks plant in Krakow (Poland) there is an estimated 5 million tonnes of landfill sludge that consists of more than 90% iron and other metal oxides. There is a global tendency to switch steel production towards carbonless technologies, which is why the presented work investigates the possibility of simultaneous waste liquidation and recovery of valuable metals with the use of hydrogenous reduction. Direct reduced iron (DRI) production was selected as the targeted technology, so the sludge was lumped and bound with cement or CaO addition. The obtained lumps were reduced in a hydrogenous atmosphere with gradual heating to 950 °C, after which their phase structure was analyzed and elemental analysis was performed. It was found that zinc evaporated during the experiment, but mostly thanks to the carbon contained in the sludge. The increased addition of binder to the sludge resulted in the enhancement of the lumps, but also limited the reduction range. The products obtained were mostly wustite and less pure iron. Taking into account the degree of reduction and the lumps' compression strength, the best binding was achieved by adding cement at a quantity of 5% mass.

3.
Nutrients ; 15(17)2023 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-37686814

RESUMO

The study aimed to analyse the macro- and micro-nutrient content in fruits of Rubus species (R. idaeus, R. occidentalis, R. chamaemorus, and R. chingii) and their varieties or hybrids from different regions. Flame atomic absorption spectrometry with deuterium background correction was used to measure concentrations of nine essential elements (K, Mg, Ca, Na, Mn, Fe, Cr, Zn, and Cu) and two heavy metals (Pb, Cd). Chemometric analysis compared the elemental profiles. Results confirmed raspberries as a rich source of macroelements (K, Mg) and microelements (Zn, Cu, Mn, Cr). The 'Bristol' cultivar consistently had the highest Fe content regardless of origin. Cr presence was observed in black raspberries for the first time. Previously observed relationships like K-Na antagonism and Cr/Zn, Fe/Zn synergism were found in raspberry fruits. Factor and cluster analyses demonstrated species and geographical diversity among Polish raspberry samples and clear separation of R. chingii from China. Raspberry fruits, due to the rich complex of polyphenols, are classified as superfoods, and the content of bioelements determined in them guarantees coverage of the daily requirement for macro- and microelements (RDA depending on the element: 5.6-204% for R. idaeus, 8.8-469, 4% for R. occidentalis, and 1.4-67.2% for R. chamaemorus), finally confirming this opinion.


Assuntos
Rubus , Meio Ambiente , Geografia , Quimiometria , China
4.
Materials (Basel) ; 15(9)2022 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-35591374

RESUMO

The article presents the results of numerical simulations of liquid steel flow in the main steelmaking ladle. The paper analyses the mechanism of the outflow of non-metallic Al2O3 and MnS inclusions with diameters in the range of 4-27 µm. The simulations were performed with ANSYS Fluent software. In order to determine the shape and size of non-metallic inclusions formed in the main ladle during steel refining, the collected samples of liquid metal were analysed using a scanning microscope with SEM/EDS and LM (light microscopy). Simulation tests and calculations were carried out for the case of steel refining under the conditions of the Cognor SA HSJ Department in Stalowa Wola (Poland). The presented method of using simulation tests to optimize the technology of steel refining in the ladle is an example. The analysis of the results shows that the gas flow in the metal volume has the greatest impact on the outflow of non-metallic inclusions in the steelmaking ladle.

5.
Materials (Basel) ; 15(4)2022 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-35208138

RESUMO

The article presents the results of analyses of numerical modelling of selected factors in electric arc furnace melts. The aim of the study was to optimise the melting process in an electric arc furnace using statistical-thermodynamic modelling based on, among other things, multiple linear regression (MLR). The article presents tools and methods which make it possible to identify the most significant indicators of the process carried out on the analysed unit from the point of view of improvement. The article presents the characteristics of the process and creation of the MLR model and, by applying its numerical analyses and results of calculations and simulations for selected variables and indicator, identifying the operation of a selected furnace. Developed model to demand of electric energy identification was used for calculations of energy balances, the distribution of the energy used in the furnace was presented.

6.
J Pharm Biomed Anal ; 195: 113863, 2021 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-33412463

RESUMO

Iris pseudacorus is one of the most widespread iris species and possesses complex secondary metabolites. Our study showed that its rhizomes are abundant with phenolic compounds of which 80 % belong to the tannin group. Methanolic extracts from garden cultured iris rhizomes possessed antibacterial activity against human Gram positive Staphylococcus aureus and Enterococcus faecalis and Gram negative Pseudomonas aeruginosa and Klebsiella pneumoniae pathogens including clinical isolates resistant to commercially available antibiotics. Moreover the extract from rhizome, in concentration 3.125 mg dry weight/mL, containing gallocatechin (1), effectively combats S. aureus biofilm. The same rhizome extract acts against human cancer cell lines, especially against estrogen positive MCF-7 breast cancer cell line (IC50 = 11.75 µg/mL). In vitro culture of excised, anatomical roots of I. pseudacorus excreted three antistaphylococcal compounds into the plant medium, detected by using TLC-overlayer bioautography. By the use of HPLC-DAD-ESIMS system 2 active compounds were identified as 5,7,4'-trihydroxy-6,3'-dimethoxy-isoflavone (7) and unknown dimethoxy-dihydroxy-isoflavone (9). I. pseudacorus as a non-edible plant might be considered to be new, easy accessible, non-wood source of biologically active polyphenolics.


Assuntos
Anti-Infecciosos , Gênero Iris , Antibacterianos/farmacologia , Humanos , Testes de Sensibilidade Microbiana , Extratos Vegetais/farmacologia , Rizoma , Staphylococcus aureus
7.
Acta Pharm ; 70(2): 201-213, 2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-31955143

RESUMO

Two-step targeted 2D planar chromatographic method (2DTLC) was used in the determination of ginkgolic acids in pharmaceuticals and dietary supplements. The choice of the extraction method and the separation technique was guided by the formulation type (capsule, tablet, tincture) with expected low amounts of ginkgolic acids in the analyzed herbal samples. Separation of ginkgolic acids C15:1 and C17:1 on HPTLC RP18 WF254s was preceded by its separation from the sample matrix on TLC Si60 F254s. Mobile phases consisted of acetonitrile/water/formic acid (80:20:1, V/V/V) and n-heptane/ethyl acetate/formic acid (20:30:1, V/V/V), resp. Identification of separated compounds was based on 2D-TLC co-chromatography with reference substances and off-line 2D-TLC x HPLC-DAD-ESI-MS analysis. Quantification of ginkgolic acids C15:1 and C17:1 was conducted densitometrically. Among the analyzed products, the presence of ginkgolic acids was confirmed only in herbal drugs containing 60 % ethanolic tinctures of Ginkgo biloba leaves. The use of TLC in the quantification of ginkgolic acids C15:1 and C17:1 in ginkgo extracts was described for the first time.


Assuntos
Ginkgo biloba/química , Extratos Vegetais/química , Salicilatos/química , Cromatografia Líquida de Alta Pressão/métodos , Suplementos Nutricionais
8.
Acta Pharm ; 68(2): 199-210, 2018 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-29702475

RESUMO

Flavonoids in the buds of eight Populus species and hybrids were detected and compared with the aid of an optimized TLC method. Separation of 17 flavonoid aglycones belonging to different groups, namely, flavones, flavonols, flavanones and flavanonols, previously described as constituents of poplar buds, was performed on silica gel plates using a hexane/ethyl acetate/formic acid (60:40:1.3, V/V/V) mixture as the mobile phase. Pinocembrin and pinostrobin were found in the majority of analyzed poplar buds. For quantitative analysis of both compounds, two TLC evaluation modes, densitometric and videodensitometric, were compared and the established methods were validated. Concentrations of flavanones in some extracts differed slightly or significantly due to the analyzed plant matrix complexity and the TLC evaluation mode applied. Poplar buds rich in flavanones originated from P. × canadensis 'Robusta' (1.82 and 2.23 g per 100 g, resp.) and P. balsamifera (1.17 and 2.24 g per 100 g, resp.).


Assuntos
Cromatografia em Camada Fina/métodos , Flavanonas/análise , Extratos Vegetais/análise , Populus/química , Densitometria/métodos , Flavanonas/química , Flavanonas/isolamento & purificação , Flavonoides/análise , Flavonoides/química , Flavonoides/isolamento & purificação , Extratos Vegetais/química
9.
Acta Pharm ; 68(1): 97-107, 2018 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-29453912

RESUMO

A new HPTLC-densitometric method for diosgenin determination in fenugreek seeds was established after optimization of the conditions for efficient saponin extraction and acid hydrolysis. Several procedures were tested, the best of which was a three-step Soxhlet extraction, followed by hydrolysis of the obtained methanolic extract with 2 mol L-1 H2SO4. Best diosgenin separation from other hydrolysis products was obtained on HPTLC Si60F254 plates u sing a mixture of n-heptane/ethyl acetate (7:3, V/V) and modified anisaldehyde as a spraying reagent. The method was preliminarily validated and the determined amounts of diosgenin in fenugreek seeds of Polish and African origin were found to be similar and ranged from 0.12-0.18 %.


Assuntos
Diosgenina/química , Sementes/química , Trigonella/química , Acetatos/química , Cromatografia Líquida de Alta Pressão/métodos , Extratos Vegetais/química , Saponinas/química
10.
Phytochem Anal ; 25(1): 29-35, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-23839972

RESUMO

INTRODUCTION: Hyoscyamine and scopolamine, anti-cholinergic agents widely used in medicine, are typically obtained from plants grown under natural conditions. Since field cultivation entails certain difficulties (changeable weather, pests, etc.), attempts have been made to develop a plant in vitro culture system as an alternative source for the production of these compounds. During experiments to locate the limiting steps in the biotechnological procedure, it is important to monitor not only the levels of the final products but also the changes in the concentration of their precursors. OBJECTIVE: To develop a HPTLC method for the separation and quantitation of the main tropane alkaloids hyoscyamine and scopolamine, their respective direct precursors littorine and anisodamine, and cuscohygrine, a product of a parallel biosynthetic pathway that shares a common precursor (N-methyl-∆(1) -pyrrolium cation) with tropane alkaloids. METHODS: Using alkaloid extracts from Atropa baetica hairy roots, different TLC chromatographic systems and developing procedures were investigated. RESULTS: Full separation of all compounds was obtained on HPTLC Si60 F254 plates preconditioned with mobile phase vapours (chloroform:methanol:acetone:25% ammonia ratios of 75:15:10:1.8, v/v/v/v). The chromatograms were developed twice (at distances of 4.0 and 3.0 cm) in a Camag twin trough chamber and visualised with Dragendorff's reagent. Densitometric detection (λ = 190 and 520 nm) was used for quantitative analyses of the different plant samples. CONCLUSION: This method can be recommended for quantitation of hyoscyamine, scopolamine, anisodamine, littorine and cuscohygrine in different plant material (field grown vs. in vitro cultures).


Assuntos
Derivados da Atropina/análise , Cromatografia em Camada Fina/métodos , Hiosciamina/análise , Escopolamina/análise , Solanaceae/química , Alcaloides de Solanáceas/análise , Acetona/análogos & derivados , Acetona/análise , Atropa/química , Atropa/metabolismo , Derivados da Atropina/metabolismo , Raízes de Plantas/química , Raízes de Plantas/citologia , Raízes de Plantas/metabolismo , Pirrolidinas/análise , Reprodutibilidade dos Testes , Solanaceae/citologia , Solanaceae/metabolismo , Alcaloides de Solanáceas/metabolismo , Técnicas de Cultura de Tecidos
11.
Acta Pol Pharm ; 70(1): 27-34, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23610956

RESUMO

The SPE-HPLC method was developed to determine an isosalipurposide (5) and its derivative, 6"-O-p-coumaroyl ester (6) in the bark of eight taxa (I-VIII) belonging to three species of the genus Salix and originating from a natural habitat or cultivated for pharmaceutical purposes. The chalcones were separated by HPLC under gradient elution with the concentration of ACN increasing from 20% to 50% in 0.1% aqueous H3PO, (tG 15 min). The content of both compounds was determined by an external standardization with the use of isoliquiritigenin (7) as a reference substance - a commercially available chalcone, and also isosalipurposide (5) and its derivative, 6"-O-p-coumaroyl ester (6). The latter compound was isolated from the bark of Salix daphnoides (IV) by a CC and semi-preparative HPLC and its structure was elucidated by MS and NMR spectra. It was stated that 6"-O-p-coumaroylisosalipurposide (6), in addition to isosalipurposide (5), is a characteristic flavonoid for the S. daphnoides species. Moreover, the presence of these two chalcones was confirmed in the bark of S. acutifolia (I). Differences were observed in the results obtained from a quantitative analysis due to the type of reference substance used. The content of chalcones was varied and dependent on the species selected for analysis, namely from 22.01/21.08 mg/g in S. daphnoides clone 1095 (III) to 2.47/2.44 mg/g in S. daphnoides (II), collected from a natural habitat. Isosalipurposide (5) was determined in all the investigated species and clones of Salix, besides a number of naringenin derivatives. Separation of all flavonoids: flavanones - naringenin (1), naringenin (+)-5-O-glucoside (2), (-)-5-O-glucoside (3), 7-O-glucoside (4) and chalcones (5 and 6) was performed under gradient elution with the same solvents and changes in ACN concentration from 2% to 37% (tG 60 min). The total amount of flavanones ranged from 4.69 mg/g in S. purpurea clone 1132 (VII) to 41.93 mg/g in S. purpuea (VIII) from Herbapol Wroclaw.


Assuntos
Chalconas/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Flavanonas/isolamento & purificação , Salix/química , Acetonitrilas/química , Calibragem , Cromatografia Líquida de Alta Pressão/normas , Limite de Detecção , Modelos Lineares , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Estrutura Molecular , Casca de Planta , Plantas Medicinais , Padrões de Referência , Salix/classificação , Extração em Fase Sólida , Solventes/química
12.
Z Naturforsch C J Biosci ; 61(7-8): 565-70, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16989318

RESUMO

Callus cultures of Vaccinium corymbosum var. bluecrop were optimized for their isoprene derivatives production by supplementing Schenk-Hildebrandt (SH) medium with constant concentration of kinetin (2.32 microM) and two different amounts of selected auxins. Every auxin, except for IBA, used in 10-time higher concentration (2,4D, NAA, IAA, NOA) stimulated biosynthesis of beta-sitosterol and inhibited triterpene synthesis. Quantitative analysis of isoprene derivatives in callus biomass collected on the 25th day of the experiment proved that the analyzed callus of Vaccinium corymbosum var. bluecrop synthesized the highest amount of isoprene derivatives after subculturing on SH medium modified with 22.6 microM of 2,4D and 2.32 microM of kinetin.


Assuntos
Hemiterpenos/biossíntese , Ácidos Indolacéticos/farmacologia , Reguladores de Crescimento de Plantas/farmacologia , Vaccinium/citologia , Vaccinium/metabolismo , Biomassa , Butadienos/metabolismo , Hemiterpenos/metabolismo , Cinetina/metabolismo , Pentanos/metabolismo , Esteróis/metabolismo , Vaccinium/efeitos dos fármacos , Vaccinium/crescimento & desenvolvimento
13.
Acta Pol Pharm ; 62(1): 45-51, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16022493

RESUMO

The phytochemical analysis of Vaccinium corymbosum var bluecrop leaves and callus biomass revealed ursolic acid, oleanolic acid, alpha-amyrin and beta-amyrin in both plant materials. Beta-sitosterol was determined only in callus biomass. The structure of isolated compounds was elucidated by TLC co-chromatography with standards and with spectroscopic methods (1H NMR, 13C NMR, EI-MS).


Assuntos
Butadienos/química , Hemiterpenos/química , Pentanos/química , Vaccinium/química , Cromatografia em Camada Fina , Espectroscopia de Ressonância Magnética , Folhas de Planta/química , Padrões de Referência , Espectrometria de Massas por Ionização por Electrospray , Técnicas de Cultura de Tecidos
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