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1.
Antibiotics (Basel) ; 12(2)2023 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-36830282

RESUMO

The essential oil of Achillea setacea was isolated by hydrodistillation and characterized by GC-MS. The antioxidant and antimicrobial activity of Achillea setacea essential oil was evaluated, as well as its biocompatibility (LDH and MTT methods). DPPH, FRAP, and CUPRAC methods were applied for antioxidant activity evaluation, while qualitative and quantitative assays (inhibition zone diameter, minimum inhibitory concentration, and minimum fungicidal concentration), NO release (by nitrite concentration determination), and microbial adhesion capacity to the inert substrate (the biofilm microtiter method) were used to investigate the antimicrobial potential. A total of 52 compounds were identified by GC-MS in A. setacea essential oil, representing 97.43% of the total area. The major constituents were borneol (32.97%), 1,8-cineole (14.94%), camphor (10.13%), artemisia ketone (4.70%), α-terpineol (3.23%), and γ-eudesmol (3.23%). With MICs ranging from 0.78 to 30 µg/mL, the A. setacea essential oil proved to inhibit the microbial adhesion and induce the NO release. To the best of our knowledge, the present study reports for the first time the antimicrobial activity of A. setacea EO against clinically and biotechnologically important microbial strains, such as Shigella flexneri, Listeria ivanovii, L. innocua, Saccharomyces cerevisiae, Candida glabrata, Aspergillus niger, Rhizopus nigricans, Cladosporium cladosporioides, and Alternaria alternata, demonstrating its antimicrobial applications beyond the clinical field.

2.
Int J Mol Sci ; 24(3)2023 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-36769008

RESUMO

To improve their biological activity, complexes [Cu(bipy)(dmtp)2(OH2)](ClO4)2·dmtp (1) and [Cu(phen)(dmtp)2(OH2)](ClO4)2·dmtp (2) (bipy 2,2'-bipyridine, phen: 1,10-phenantroline, and dmtp: 5,7-dimethyl-1,2,4-triazolo [1,5-a]pyrimidine) were included in ß-cyclodextrins (ß-CD). During the inclusion, the co-crystalized dmtp molecule was lost, and UV-Vis spectra together with the docking studies indicated the synthesis of new materials with 1:1 and 1:2 molar ratios between complexes and ß-CD. The association between Cu(II) compounds and ß-CD has been proven by the identification of the components' patterns in the IR spectra and powder XRD diffractograms, while solid-state UV-Vis and EPR spectra analysis highlighted a slight modification of the square-pyramidal stereochemistry around Cu(II) in comparison with precursors. The inclusion species are stable in solution and exhibit the ability to scavenge or trap ROS species (O2·- and HO·) as indicated by the EPR experiments. Moreover, the two inclusion species exhibit anti-proliferative activity against murine melanoma B16 cells, which has been more significant for (2)@ß-CD in comparison with (2). This behavior is associated with a cell cycle arrest in the G0/G1 phase. Compared with precursors, (1a)@ß-CD and (2a)@ß-CD exhibit 17 and 26 times more intense activity against planktonic Escherichia coli, respectively, while (2a)@ß-CD is 3 times more active against the Staphylococcus aureus strain.


Assuntos
Cobre , beta-Ciclodextrinas , Animais , Camundongos , Cobre/química , Cristalografia por Raios X , beta-Ciclodextrinas/farmacologia , beta-Ciclodextrinas/química , Antibacterianos/farmacologia , Espectrofotometria Infravermelho
3.
Micromachines (Basel) ; 13(8)2022 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-36014134

RESUMO

Guaifenesin (GFS), phenylephrine (PHE) and paracetamol (PAR), drugs used in combination for the relief of cold and flu symptoms, were determined at electrochemically pretreated pencil graphite electrode. Differential pulse voltammetry (DPV) was used for the first time for the concomitant determination of the target compounds based on the electro-oxidation of PAR at 0.43 V, PHE at 0.74 V and GFS at 1.14 V in Britton-Robinson buffer pH 6.0. Under optimized experimental conditions, two linear ranges were obtained for PAR (2.50 × 10-6 M-1.00 × 10-5 M and 1.00 × 10-5 M-1.00 × 10-4 M) and for PHE and GFS linearity was proved between 5.00 × 10-6 M-2.00 × 10-4 M and 2.50 × 10-6 M-2.00 × 10-4 M, respectively. The detection limits were 8.12 × 10-7 M for PAR, 1.80 × 10-6 M for PHE and 8.29 × 10-7 M for GFS. The selective and sensitive DPV method and the electrochemically treated electrode were employed for simultaneous analysis of the analytes in pharmaceutical samples with good recoveries.

4.
Antioxidants (Basel) ; 11(5)2022 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-35624823

RESUMO

This paper evaluated the chemical and biological properties of bee pollen samples from Romania. Firstly, the bee pollen alcoholic extracts (BPEs) were obtained from raw bee pollen harvested by Apis mellifera carpatica bees. The chemical composition of BPE was obtained by determination of total phenol content and total flavonoid content, UHPLC-DAD-ESI/MS analysis of phenolic compounds, and GC-MS analysis of fatty acids, esters, and terpenes. Additionally, the antioxidant activity was evaluated by the Trolox Equivalent Antioxidant Capacity method. Furthermore, the biological properties of BPE were evaluated (antimicrobial and cytotoxic activity). The raw BP samples studied in this paper had significant phenolic acid and flavonoid content, and moderate fatty acid, ester, and terpene content. P1, P2, and P4 have the highest TPC and TFC levels, and the best antioxidant activity. All BPEs studied had antimicrobial activity on pathogenic strains isolated from the clinic or standard strains. A synergistic antimicrobial effect of the BPEs was observed along with the soluble compounds of L. rhamnosus MF9 and E. faecalis 2M17 against some pathogenic (clinical) strains and, considering the tumour proliferation inhibitory activity, makes BP a potential prebiotic and antitumour agent for the gut environment.

5.
Molecules ; 26(11)2021 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-34074063

RESUMO

The purpose of this paper was to characterize and investigate the antimicrobial potential of Amorpha fruticosa fruits essential oil (EO). The EO was extracted by hydrodistillation, analyzed by GC-MS, and then evaluated for its interaction with microbial and mammalian cells. The antimicrobial activity was assessed against bacterial and fungal strains, in a planktonic and adherent growth state, using qualitative and quantitative assays. The main components identified in A. fruticosa fruits EO were δ-cadinene, γ-muurolene, and α-muurolene. The Gram-positive strains proved to be more susceptible than Gram-negative bacteria and fungal strains. The EO exhibited good antibiofilm activity, inhibiting the microbial adherence to the inert (96-well plates and Foley catheter section) and cellular substrata. The flow cytometry analysis revealed as one of the possible mechanisms of antimicrobial action the alteration of cell membrane hydrophobicity. The cytotoxicity on the L929 cell line occurred at concentrations higher than 0.3 mg/mL. Taken together, our results demonstrate that A. fruticosa fruits EO contains active compounds with selective inhibitory effect on different microbial strains in planktonic and biofilm growth state, explained at least partially by the interference with microbial membranes due to their hydrophobic character.


Assuntos
Fabaceae/química , Óleos Voláteis/química , Óleos Voláteis/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Interações Hidrofóbicas e Hidrofílicas , Testes de Sensibilidade Microbiana
6.
Environ Monit Assess ; 188(9): 535, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27566323

RESUMO

The purpose of this study was to monitor and record the specific characteristics and properties of the Arges River water in the Budeasa Reservoir (the principal water resources of municipal tap water of the big Romanian city Pitesti and surrounding area) for a period of 5 years (2005-2009). The monitored physical and chemical parameters were turbidity, pH, electrical conductivity, chemical oxygen demand, 5 days biochemical oxygen demand, free dissolved oxygen, nitrite, nitrate, ammonia nitrogen, chloride, total dissolved iron ions, sulfate, manganese, phosphate, total alkalinity, and total hardness. The results were discussed in correlation with the precipitation values during the study. Monthly and annual values of each parameter determined in the period January 2005-December 2009 were used as a basis for the classification of Budeasa Reservoir water, according to the European legislation, as well as for assessing its quality as a drinking water supply. Principal component analysis and Pearson correlation coefficients were used as statistical procedures in order to evaluate the data obtained during this study.


Assuntos
Monitoramento Ambiental , Rios/química , Qualidade da Água , Análise da Demanda Biológica de Oxigênio , Água Doce/química , Nitratos/análise , Nitritos/análise , Fosfatos/análise , Análise de Componente Principal , Romênia , Abastecimento de Água
7.
J Food Sci Technol ; 53(6): 2589-96, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27478214

RESUMO

The quasi-reversible, diffusion controlled behavior of rosmarinic acid (RA) on a disposable pencil graphite electrode (PGE) was established by cyclic voltammetry. Using the anodic oxidation peak presented by RA on the PGE a differential pulse voltammetric (DPV) method was developed for the quantitative determination of RA. The linear range was 10(-8) - 10(-5) M RA and the detection and quantification limits were 7.93 × 10(-9) M and 2.64 × 10(-8) M RA, respectively. The applicability of the developed method was tested by recovery studies and by the assessment of the total polyphenolic contents (TPCDPV) of green, white and black Turkish teas, which were found to be 40.74, 30.04 and 23.97 mg rosmarinic acid equivalent/g dry tea, respectively. These results were in good agreement with those obtained by the Folin-Ciocalteu method. The developed method is a sensitive and cheap tool for the rapid and precise evaluation of TPCDPV of tea samples.

8.
Nat Prod Commun ; 11(4): 551-5, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27396216

RESUMO

The hydrodistilled essential oils and volatile compounds (by static headspaces technique) of Mentha piperita L. and M spicata L. were characterized by GC-MS. Headspace analysis of Mentha piperita revealed the existence of menthone (25.4%), 1,8-cineole (17.7%) and menthol (12.1%) as the main components, while the essential oil contained high amounts of menthol (46.8%) and menthone (25.6%). By contrast, headspace analysis of M. spicata showed a high content of limonene (37.0%) together with carvone (13.0%), ß-pinene (10.4%) and α-pinene (9.8%), while the essential oil was reach in carvone (51.7%), dihydrocarveol (11.5%) and cis-dihydrocarvone (9.1%). Eleven samples of peppermint tea available on the Romanian market were analysed by headspace GC-MS. The volatile profile of the tea samples was compared with that of Mentha piperita L. and certain differences were emphasized and discussed.


Assuntos
Mentha piperita/química , Mentha spicata/química , Óleos Voláteis/química , Chá/química , Compostos Orgânicos Voláteis/química
9.
J Chromatogr Sci ; 54(9): 1567-1572, 2016 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-27334291

RESUMO

This article describes a novel HPLC method able to quantify four active substances: tylosin tartrate, prednisolone, chloramphenicol and vitamin B12 and one excipient benzyl alcohol for the first time in <15 min. The analysis was conducted using a HyPurity Advance chromatographic column, a binary mobile phase which contains water (60%) and methanol (40%) as organic modifiers delivered isocratically at room temperature. The detection was established to be optimum at 260 nm. Limit of detection and limit of quantification were established experimentally, using the ratio signal-to-noise methodology. The method was validated in accordance with ICH and USP guidelines with respect to selectivity, linearity, limits of detection and quantitation, accuracy, precision and robustness and was applied on commercial available veterinary drug.

10.
Chem Biodivers ; 12(10): 1554-64, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26460560

RESUMO

The essential oil extracted by hydrodistillation from Romanian Artemisia annua aerial parts was characterized by GC/MS analysis, which allowed the identification of 94.64% of the total oil composition. The main components were camphor (17.74%), α-pinene (9.66%), germacrene D (7.55%), 1,8-cineole (7.24%), trans-ß-caryophyllene (7.02%), and artemisia ketone (6.26%). The antimicrobial activity of this essential oil was evaluated by determining the following parameters: minimal inhibitory concentration (MIC), minimal bactericidal concentration (MBC), minimal fungicidal concentration (MFC), and minimal biofilm eradication concentration (MBEC). Moreover, the soluble virulence factors were quantified with different biochemical substrates incorporated in the culture media. The reference and resistant, clinical strains proved to be susceptible to the A. annua oil, with MICs ranging from 0.51 to 16.33 mg/ml. The tested essential oil also showed good antibiofilm activity, inhibiting both the initial stage of the microbial cell adhesion to the inert substratum and the preformed mature biofilm. When used at subinhibitory concentrations, the essential oil proved to inhibit the phenotypic expression of five soluble virulence factors (hemolysins, gelatinase, DNase, lipases, and lecithinases). Briefly, the present results showed that the A. annua essential oil contained antimicrobial compounds with selective activity on Gram-positive and Gram-negative bacterial strains as well as on yeast strains and which also interfere with the expression of cell-associated and soluble virulence factors.


Assuntos
Antibacterianos/farmacologia , Antifúngicos/farmacologia , Artemisia annua/química , Bactérias/efeitos dos fármacos , Fungos/efeitos dos fármacos , Óleos Voláteis/farmacologia , Antibacterianos/química , Antibacterianos/isolamento & purificação , Antifúngicos/química , Antifúngicos/isolamento & purificação , Biofilmes/efeitos dos fármacos , Relação Dose-Resposta a Droga , Testes de Sensibilidade Microbiana , Óleos Voláteis/química , Óleos Voláteis/isolamento & purificação , Componentes Aéreos da Planta/química , Romênia , Relação Estrutura-Atividade
11.
Food Chem ; 173: 1059-65, 2015 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-25466125

RESUMO

The present paper describes the voltammetric behaviour and the quantitative determination of caffeic acid (CA) on a disposable pencil graphite electrode (PGE). The anodic peak current of CA recorded by differential pulse voltammetry (DPV) varies linearly with CA concentration in the range 1×10(-7)-3×10(-3) M. The detection and quantification limits were 8.83×10(-8) M and 2.94×10(-7) M caffeic acid, respectively. The mean recoveries of CA from Turkish green, white and black teas were 98.30%, 99.57% and 91.46%. For these three tea types the corresponding total polyphenolic contents (TPCs) evaluated by DPV on PGE were 35.81, 34.59 and 31.21 mg caffeic acid equivalent/g tea, respectively. These TPC values were in good accordance with those obtained by the Folin-Ciocalteu method. The developed DPV on PGE method constitutes a simple and inexpensive tool for the rapid assessment of TPC of tea samples.


Assuntos
Ácidos Cafeicos/química , Técnicas Eletroquímicas/instrumentação , Eletrodos , Grafite , Polifenóis/análise , Chá/química , Técnicas Eletroquímicas/métodos
12.
Environ Monit Assess ; 185(3): 2367-75, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22707150

RESUMO

A new HPLC method was developed for the simultaneous determination of aminophenol isomers by means of a mixed-mode stationary phase containing both SCX and C18 moieties. All factors influencing the separation were discussed and optimized. The chromatographic conditions for the separation of aminophenols are the stationary phase duet SCX/C18, the mobile phase of aqueous phosphate buffer (pH 4.85):methanol = 85:15 (v/v) delivered with a flow rate of 1 mL/min and a detection at 285 nm. The method proposed was validated in terms of linearity, limits of detection and quantification, accuracy and precision. The HPLC method elaborated here was applied with good results on river water samples. In order to survey the quality of surface rivers entered in treatment plants which deliver water for Bucharest, two major rivers were included in a monitoring program which last more than 1 year.


Assuntos
Aminofenóis/análise , Monitoramento Ambiental/métodos , Água Doce/química , Poluentes Químicos da Água/análise , Aminofenóis/química , Cromatografia Líquida de Alta Pressão/métodos , Isomerismo , Romênia , Poluentes Químicos da Água/química
13.
Environ Monit Assess ; 184(10): 6061-70, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22068312

RESUMO

The level of three alkylphenols (APs) 4-nonylphenol, 4-octylphenol and 4-tert-octylphenol was monitored in various water samples using a new developed and validated HPLC method. The HPLC method employed a column with a mixed-mode stationary phase (C18/SCX) using a mobile phase of water to methanol = 15:85 (v/v) delivered at a flow rate of 1 mL/min at room temperature. Both diode array, DAD and fluorescence, FLD detectors were employed. The method is linear when APs concentration ranged from 0.025 to 0.5 µg/mL with a DAD detection at 279 nm and between 0.0008 and 0.1 µg/mL when the detection was made by FLD (excitation at 220 nm, emission at 315 nm). The limit of detection and limit of quantitation for alkylphenols were found to be 5 and 15 ng/mL, respectively (detection by DAD). The method was employed with good results for the determination of APs in the presence of polycyclic aromatic hydrocarbons in various water samples.


Assuntos
Fenóis/análise , Poluentes Químicos da Água/análise , Cromatografia Líquida de Alta Pressão , Monitoramento Ambiental , Fenóis/química , Poluentes Químicos da Água/química
14.
Environ Monit Assess ; 184(5): 2783-95, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-21688033

RESUMO

A simple, sensitive and reliable HPLC-FLD method for the routine determination of 4-nonylphenol, 4-NP and 4-tert-octylphenol, 4-t-OP content in water samples was developed. The method consists in a liquid-liquid extraction of the target analytes with dichloromethane at pH  3.0-3.5 followed by the HPLC-FLD analysis of the organic extract using a Zorbax Eclipse XDB C8 column, isocratic elution with a mixed solvent acetonitrile/water 65:35, at a flow rate of 1.0 mL/min and applying a column temperature of 40°C. The method was validated and then applied with good results for the determination of 4-NP and 4-t-OP in Ialomita River water samples collected each month during 2006. The concentration levels of 4-NP and 4-t-OP vary between 0.08-0.17 µg/L with higher values of 0.24-0.37 µg/L in the summer months for 4-NP, and frequently <0.05 µg/L but also between 0.06-0.09 µg/L with higher values of 0.12-0.16 µg/L in July and August for 4-t-OP and were strongly influenced by sesonial and anthropic factors. The method was also applied on samples collected over 2 years 2007 and 2008 from urban wastewaters discharged into sewage or directly into the rivers by economic agents located in 30 Romanian towns. Good results were obtained when the method was used for analysis of effluents discharged into surface waters by 16 municipal wastewater treatment plants, during the year 2008.


Assuntos
Monitoramento Ambiental/métodos , Fenóis/análise , Poluentes Químicos da Água/análise , Cromatografia Líquida de Alta Pressão , Rios/química , Romênia , Poluição Química da Água/estatística & dados numéricos
15.
Environ Monit Assess ; 173(1-4): 79-89, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20213061

RESUMO

Romania is one of the countries that have natural arsenic groundwater problems. This paper presents the results of a study of arsenic concentration monitoring in natural mineral waters collected from 23 sampling sites located in the northern, central, and western regions of Romania. The sampling sites are both natural springs and drilled wells. The graphite furnace atomic absorption spectrometry was used for arsenic content determination. The Piper's classification principle was applied in order to find out the hydrochemical type of the analyzed waters. Depending on the concentration of arsenic, the water analyzed can be classified into three main categories: (1) mineral natural waters containing less than 10 µg/L arsenic, (2) mineral natural waters containing arsenic at concentrations several times higher than the limit of 10 µg/L but less than 100 µg/L, and (3) mineral natural waters containing arsenic at concentrations of ten to a hundred times higher than the allowed limit of 10 µg/L. The last-mentioned waters are of bicarbonatate sodium type and were sampled from seven sources only, being prohibited for human and animal use.


Assuntos
Arsênio/análise , Poluentes Químicos da Água/análise , Abastecimento de Água/análise , Monitoramento Ambiental/métodos , Romênia
16.
Environ Monit Assess ; 165(1-4): 113-23, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19421886

RESUMO

This paper reports the results obtained for the determination of Ba concentrations in mineral groundwater samples collected from drilled outlets located in the counties of Covasna and Harghita (34 sampling points), in five expeditions (spring, summer, and autumn), during 3 years: 2005, 2006, and 2007. The experimental data show that there are some sampling sites in which the barium concentration exceeds 1 mg/L, which is the maximum concentration admitted for barium. These mineral natural waters could be used only for therapeutic purposes. All other analyzed natural mineral waters are proper as both drinking and therapeutic water. By means of a principal component analysis a statistical approach was performed, using the data obtained during those analyzing processes. The distribution of the water saturation indexes with respect to a series of mineral species (alstonite, barite, barytocalcite, nitrobarite, sanbornite, and witherite) suggests that barium tends to remain in solution as ionic species in different concentrations and to be further carried away as such.


Assuntos
Bário/análise , Águas Minerais/análise , Poluentes Químicos da Água/análise , Monitoramento Ambiental/métodos , Romênia
17.
J Agric Food Chem ; 57(22): 10497-504, 2009 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-19877635

RESUMO

This paper presents the development, optimization and validation of a new HPLC method used for the separation and determination of zearalenone, ZON, and its metabolites in biological samples of Leghorn broiler. ZON and its metabolites can be separated with good resolution in 11 min, using a Hypersil Gold C18 column, a mobile phase mixture of 50 mM aqueous ammonium acetate:acetonitrile:methanol, 45:8:47 (v/v/v), flow rate 1 mL/min and column temperature 40 degrees C. Based on the results obtained by this method applied on biological samples one can conclude that liver is the site for zearalenone localization and detoxification. Influence of zearalenone on the nutritional properties of broiler meat (weight variation, gross chemical composition, fatty acids profile of the meat) was studied, also. Results obtained during 4 days of treatment with ZON showed minimal or no effects of the dietary zearalenone on broiler meat nutritional quality.


Assuntos
Galinhas , Cromatografia Líquida de Alta Pressão/métodos , Carne/análise , Valor Nutritivo , Zearalenona/efeitos adversos , Zearalenona/análise , Animais , Ácidos Graxos/análise , Fígado/química , Zearalenona/metabolismo
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