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1.
Sci Rep ; 14(1): 14753, 2024 06 26.
Artigo em Inglês | MEDLINE | ID: mdl-38926522

RESUMO

The development of nanomaterials has been speedily established in recent years, yet nanoparticles synthesized by traditional methods suffer unacceptable toxicity and the sustainability of the procedure for synthesizing such nanoparticles is inadequate. Consequently, green biosynthesis, which employs biopolymers, is gaining attraction as an environmentally sound alternative to less sustainable approaches. Chitosan-encapsulated nanoparticles exhibit exceptional antibacterial properties, offering a wide range of uses. Chitosan, obtained from shrimp shells, aided in the environmentally friendly synthesis of high-purity zinc oxide nanoparticles (ZnO NPs) with desirable features such as the extraction yield (41%), the deacetylation (88%), and the crystallinity index (74.54%). The particle size of ZnO NPs was 12 nm, while that of chitosan-ZnO NPs was 21 nm, and the bandgap energies of these nanomaterials were 3.98 and 3.48, respectively. The strong antibacterial action was demonstrated by ZnO NPs, chitosan-ZnO NPs, and chitosan-ZnO/PVP, particularly against Gram-positive bacteria, making them appropriate for therapeutic use. The photocatalytic degradation abilities were also assessed for all nanoparticles. At a concentration of 6 × 10-5 M, chitosan removed 90.5% of the methylene blue (MB) dye, ZnO NPs removed 97.4%, chitosan-coated ZnO NPs removed 99.6%, while chitosan-ZnO/PVP removed 100%. In the case of toluidine blue (TB), at a concentration of 4 × 10-3 M, the respective efficiencies were 96.8%, 96.8%, 99.5%, and 100%, respectively. Evaluation of radical scavenger activity revealed increased scavenging of ABTS and DPPH radicals by chitosan-ZnO/PVP compared to individual zinc oxide or chitosan-ZnO, where the IC50 results were 0.059, 0.092, 0.079 mg/mL, respectively, in the ABTS test, and 0.095, 0.083, 0.061, and 0.064 mg/mL in the DPPH test, respectively. Moreover, in silico toxicity studies were conducted to predict the organ-specific toxicity through ProTox II software. The obtained results suggest the probable safety and the absence of organ-specific toxicity with all the tested samples.


Assuntos
Antibacterianos , Quitosana , Óxido de Zinco , Quitosana/química , Quitosana/farmacologia , Óxido de Zinco/química , Óxido de Zinco/farmacologia , Antibacterianos/farmacologia , Antibacterianos/química , Antibacterianos/síntese química , Catálise , Nanopartículas/química , Testes de Sensibilidade Microbiana , Nanopartículas Metálicas/química , Compostos de Bifenilo/química , Química Verde
2.
Anal Methods ; 16(25): 4187-4197, 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38881497

RESUMO

An alternative method of rice sample preparation for measuring the total content of selected elements, i.e., Al, Ba, Ca, Cu, Fe, K, Mg, Mn, Na, Sr and Zn, by ICP OES was developed. The proposed approach is based on the ultrasound-assisted extraction (USAE) of rice samples in the presence of a small amount of concentrated HNO3. The optimal operating parameters were found using the design of experiments (DOE) approach, and the studied experimental factors were the temperature of the ultrasonic bath (A), the sonication time (B), and the volume of concentrated HNO3 added per 0.5 g of a rice sample (C). Under the optimal conditions of the USAE procedure, i.e., A = 60 °C, B = 16 min and C = 4.0 mL, the rice samples were readily solubilized, and the obtained sample solutions could be analyzed by ICP OES with the simple standard solution calibration (without matrix matching). The analysis of the certified reference material (rice flour, NIST SRM 1568b) confirmed the satisfactory trueness of the USAE-ICP OES method. Additionally, no statistically significant differences between the results obtained for the samples prepared by USAE and open-vessel wet digestion (WD, the reference method) were found. In comparison to the routinely used microwave-assisted digestion and open-vessel digestion, the USAE approach offers lower acid consumption, lower detection limits (LODs) of elements, ranging from 4.0 ng g-1 for Mn to 2.7 µg g-1 for K, and a much shorter time of sample preparation.

3.
Molecules ; 29(12)2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38930977

RESUMO

Specialized chemicals are used for intensifying food production, including boosting meat and crop yields. Among the applied formulations, antibiotics and pesticides pose a severe threat to the natural balance of the ecosystem, as they either contribute to the development of multidrug resistance among pathogens or exhibit ecotoxic and mutagenic actions of a persistent character. Recently, cold atmospheric pressure plasmas (CAPPs) have emerged as promising technologies for degradation of these organic pollutants. CAPP-based technologies show eco-friendliness and potency for the removal of organic pollutants of diverse chemical formulas and different modes of action. For this reason, various types of CAPP-based systems are presented in this review and assessed in terms of their constructions, types of discharges, operating parameters, and efficiencies in the degradation of antibiotics and persistent organic pollutants. Additionally, the key role of reactive oxygen and nitrogen species (RONS) is highlighted. Moreover, optimization of the CAPP operating parameters seems crucial to effectively remove contaminants. Finally, the CAPP-related paths and technologies are further considered in terms of biological and environmental effects associated with the treatments, including changes in antibacterial properties and toxicity of the exposed solutions, as well as the potential of the CAPP-based strategies for limiting the spread of multidrug resistance.


Assuntos
Pressão Atmosférica , Gases em Plasma , Gases em Plasma/química , Poluentes Ambientais/química , Indústria Alimentícia , Antibacterianos/química , Antibacterianos/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Compostos Orgânicos/química
4.
Toxicol In Vitro ; 98: 105846, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38754599

RESUMO

Progressive incidence and a pessimistic survival rate of breast cancer in women worldwide remains one of the most concerning topics. Progressing research indicates a potentially high effectiveness of use cold atmospheric plasma (CAP) systems. The undoubted advantage seems its simplicity in combination with other anti-cancer modalities. Following observed trend of studies, one inventory CAP system was applied to directly treat human breast cancer cell lines and culturing in two different Plasma Activated Media (PAM) for combined utilization. Proposed CAP treatments on MCF-10 A, MCF-7, and MDA-MB-231 cell lines were studied in terms of impact on cell viability by MTT assay. Disturbances in cell motility following direct and combined CAP application were assessed by scratch test. Finally, the induction of apoptosis and necrosis was verified with annexin V and propidium iodide staining. Reactive species generated during CAP treatment were determined based on optical emission spectrometry analysis along with colorimetric methods to qualitatively assess the NO2-, NO3-, H2O2, and total ROS with free radicals concentration. The most effective approach for CAP utilization was combined treatment, leading to significant disruption in cell viability, motility and mostly apoptosis induction in breast cancer cell lines. Determined CAP dose allows for mild outcome, showing insignificant harm for the non-cancerous MCF-10 A cell line, while the highly aggressive MDA-MB-231 cell line shows the highest sensitivity on proposed CAP treatment. Direct CAP treatment seems to drive the cells into the sensitive state in which the effectiveness of PAM is boosted. Observed anti-cancer response of CAP treatment was mostly triggered by RNS (mostly NO2- ions) and ROS along with free radicals (such as H2O2, OH•, O2-•, 1O2, HO2•). The combined application of one CAP source represent a promising alternative in the development of new and effective modalities for breast cancer treatment.


Assuntos
Apoptose , Neoplasias da Mama , Movimento Celular , Sobrevivência Celular , Gases em Plasma , Espécies Reativas de Oxigênio , Humanos , Gases em Plasma/farmacologia , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Sobrevivência Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Feminino , Linhagem Celular Tumoral , Espécies Reativas de Oxigênio/metabolismo , Antineoplásicos/farmacologia
5.
ACS Biomater Sci Eng ; 9(12): 6632-6643, 2023 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-37982239

RESUMO

Atmospheric pressure plasma treatments are nowadays gaining importance to improve the performance of biomaterials in the orthopedic field. Among those, magnesium phosphate-based cements (MPCs) have recently shown attractive features as bone repair materials. The effect of plasma treatments on such cements, which has not been investigated so far, could represent an innovative strategy to modify MPCs' physicochemical properties and to tune their interaction with cells. MPCs were prepared and treated for 5, 7.5, and 10 min with a cold atmospheric pressure plasma jet. The reactive nitrogen and oxygen species formed during the treatment were characterized. The surfaces of MPCs were studied in terms of the phase composition, morphology, and topography. After a preliminary test in simulated body fluid, the proliferation, adhesion, and osteogenic differentiation of human mesenchymal cells on MPCs were assessed. Plasma treatments induce modifications in the relative amounts of struvite, newberyite, and farringtonite on the surfaces on MPCs in a time-dependent fashion. Nonetheless, all investigated scaffolds show a good biocompatibility and cell adhesion, also supporting osteogenic differentiation of mesenchymal cells.


Assuntos
Osteogênese , Fosfatos , Humanos , Teste de Materiais , Fosfatos/farmacologia , Fosfatos/química , Pressão Atmosférica
6.
Molecules ; 28(18)2023 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-37764393

RESUMO

The qualitative X-ray phase analysis of natural and artificial food sweeteners was applied to trace the authenticity of such food additives. The mineral composition of different sweeteners commonly added to foods was studied to estimate their mineral profiles and assess the risk related to the toxic elements intake caused by sweetener consumption. The concentration of twenty elements (Ag, Al, B, Ba, Bi, Ca, Cd, Co, Cr, Cu, Fe, Mg, Mn, Mo, Ni, Pb, Sr, Ti, V, and Zn) was measured using the inductively coupled plasma-optical emission spectroscopy (ICP-OES) method after the representative samples were wet-digested with a concentrated nitric acid and hydrogen peroxide mixture in a closed-vessel microwave-assisted system. Differences between the mineral compositions of the examined sweeteners were statistically evaluated and discussed. The relationships between the concentrations of the elements determined in the analyzed sweeteners were also investigated. The successful application of the X-ray powder diffraction method proved the identity of all investigated sweeteners; all the analyzed products contained the expected sweetening agent. The results of the quantification of all the elements in the examined sweeteners indicated that these products cannot be considered nutritionally dense. Hence, the presence of toxic elements like Cd, Cr, Ni, and Pb distinctly indicates the need to test such products to guarantee their quality and ensure consumer safety.


Assuntos
Oligoelementos , Oligoelementos/análise , Edulcorantes , Cádmio , Chumbo , Minerais
7.
Nanomaterials (Basel) ; 13(17)2023 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-37686933

RESUMO

The green approach-based nanoparticle synthesis is considered a more cost-effective and ecologically responsible method of producing nanoparticles than other standard techniques. A major accomplishment in resolving these issues is the use of nanoparticles for environmental pollution remediation. This article describes a simple method for producing MgO and ZnO nanoparticles (NPs) using aqueous extracts of Zingiber officinale and Glycyrrhiza roots as the stabilizing and reducing agents, respectively. Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy-dispersed X-ray (EDX) spectroscopy methods were used to characterize the biologically synthesized metal oxide nanoparticles (MO NPs). The XRD results showed that the mean crystallite sizes of synthesized ZnO and MgO NPs, which have excellent purity, are 12.35 nm and 4.83 nm, respectively. The spherical or elliptical shape of the synthesized NPs was confirmed by the SEM analysis. The antibacterial activity of the synthesized NPs against both Gram-negative and Gram-positive bacteria was thoroughly investigated. With a medium zone of inhibition of 7 to 10 mm, the as-synthesized MgO NPs and ZnO NPs demonstrated moderate antibacterial activity towards various bacterial strains.

8.
J Pharm Biomed Anal ; 236: 115682, 2023 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-37660547

RESUMO

The analysis of homeopathic medicines for the content of total inorganic As by hydride generation (HG) hyphenated with the ICP OES detection was presented. Various forms of medicaments (sugar pellets, tablets, alcohol-based drops), containing Arsenicum album or Arsenicum iodatum in several potencies (C9-200, D6-10), as well as different sample preparation approaches (wet digestion, extraction, dissolution, dilution, direct analysis) before spectrometric measurements were studied. The influence of the undecomposed sample matrix (mainly sugar and alcohol) on the HG process of As was examined in detail. Under optimal conditions found, simplified sample preparation procedures for the determination of As traces were proposed. The suitable sensitivity, the limit of detection of As < 0.1 ng g-1, the precision within 0.31-7.4 % (as RSD), and the adequate trueness (94.9-113 % as confirmed by the recovery test) were achieved. Using the species-selective HG conditions and the developed direct analysis method, the speciation of As in arsenic drops without any prior chromatographic separation of As(III) and As(V) was carried out. The applicability of the developed strategies was demonstrated by the determination of As in 13 homeopathic products available on the Polish market.

9.
Sci Rep ; 13(1): 12789, 2023 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-37550421

RESUMO

Nitroaromatic compounds (NACs) are key contaminants of anthropogenic origin and pose a severe threat to human and animal lives. Although the catalytic activities of Re nanostructures (NSs) are significantly higher than those of other heterogeneous catalysts containing NSs, few studies have been reported on the application of Re-based nanocatalysts for NAC hydrogenation. Accordingly, herein, catalytic reductions of nitrobenzene (NB), 4-nitrophenol (4-NP), 2-nitroaniline (2-NA), 4-nitroaniline (4-NA), and 2,4,6-trinitrophenol (2,4,6-TNP) over new Re-based heterogeneous catalysts were proposed. The catalytic materials were designed to enable effective syntheses and stabilisation of particularly small Re structures over them. Accordingly, catalytic hydrogenations of NACs under mild conditions were significantly enhanced by Re sub-nanostructures (Re-sub-NSs). The highest pseudo-first-order rate constants for NB, 4-NP, 2-NA, 4-NA, and 2,4,6-TNP reductions over the catalyst acquired by stabilising Re using bis(3-aminopropyl)amine (BAPA), which led to Re-sub-NSs with Re concentrations of 16.7 wt%, were 0.210, 0.130, 0.100, 0.180, and 0.090 min-1, respectively.

10.
Environ Res ; 231(Pt 3): 116297, 2023 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-37268206

RESUMO

The common utilization of antimicrobial agents in medicine and veterinary creates serious problems with multidrug resistance spreading among pathogens. Bearing this in mind, wastewaters have to be completely purified from antimicrobial agents. In this context, a dielectric barrier discharge cold atmospheric pressure plasma (DBD-CAPP) system was used in the present study as a multifunctional tool for the deactivation of nitro-based pharmacuticals such as furazolidone (FRz) and chloramphenicol (ChRP) in solutions. A direct approach was applied to this by treating solutions of the studied drugs by DBD-CAPP in the presence of the ReO4- ions. It was found that Reactive Oxygen Species (ROS) and Reactive Nitrogen Species (RNS), generated in the DBD-CAPP-treated liquid, played a dual role in the process. On the one hand, ROS and RNS led to the direct degradation of FRz and ChRP, and on the other hand, they enabled the production of Re nanoparticles (ReNPs). The produced in this manner ReNPs consisted of catalytically active Re+4, Re+6, and Re+7 species which allowed the reduction of -NO2 groups contained in the FRz and ChRP. Unlike the DBD-CAPP, the catalytically enhanced DBD-CAPP led to almost FRz and ChRP removals from studied solutions. The catalytic boost was particularly highlighted when catalyst/DBD-CAPP was operated in the synthetic waste matrix. Re-active sites in this scenario led to the facilitated deactivation of antibiotics, achieving significantly higher FRz and ChRP removals than DBD-CAPP on its own.


Assuntos
Anti-Infecciosos , Gases em Plasma , Rênio , Antibacterianos/farmacologia , Espécies Reativas de Oxigênio , Gases em Plasma/química , Cloranfenicol , Furazolidona , Pressão Atmosférica
11.
Molecules ; 28(8)2023 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-37110609

RESUMO

A fully validated inductively coupled plasma optical emission spectrometry (ICP-OES)-based method combined with a simplified sample preparation procedure for the determination of up to 15 elements (Al, Ba, Ca, Cd, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, Pb, Sr, and Zn) in caffeinated yerba mate (YM) drinks was proposed. Various "green" treatments (acidification or dilution with a HNO3 solution and direct analysis of untreated YM with or without sonication (US)) that could replace the traditional total sample decomposition before spectrometric measurements were tested and compared. The key selection parameter was the analytical performance of the ICP-OES method obtained with each sample preparation procedure in terms of the precision and the trueness of results and limits of detection (LODs) of elements. It was found that the acidification of YMs with concentrated HNO3 to 5%, supported by US (10 min, room temperature (RT)), provided the best results, i.e., LODs at 0.11-8.5 ng g-1, precision below 5%, and trueness better than 5% (97.0%-105% as recoveries). Eleven YM drinks, commercially available on the Polish market, were analyzed with the proposed method. In addition to the mineral content, the concentration of caffeine in all analyzed YMs was determined and compared. Finally, the studies were completed by determining the bioaccessible fraction of selected elements and caffeine in YMs using in vitro gastrointestinal digestion (GID) in order to evaluate the nutritional value/risk assessment of these drinks. Accordingly, the bioaccessibility of nutritious elements (Ca, Fe, Mg, Mn, Zn) and caffeine was within 40%-59%. Except for Mn, it was established that by drinking daily 1 L of YMs, the recommended dietary intakes (RDIs) of the aforementioned essential elements were covered to a low degree (<4.5%). Hence, they are not an important source of these elements in the human diet. On the other hand, potentially toxic elements (Al, Ba, Sr) were found in a relatively inert form. Opposite to minerals, YMs can supply human organisms with quite high amounts of natural caffeine in bioaccessible form (31-70 mg per serving).


Assuntos
Ilex paraguariensis , Oligoelementos , Humanos , Cafeína , Oligoelementos/análise , Análise Espectral/métodos , Limite de Detecção
12.
Biol Trace Elem Res ; 201(12): 5871-5883, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36940037

RESUMO

Silica (SiO2), a component of the earth's crust, has been in use for many nanotechnological applications. This review presents one of the newest methods for safer, more affordable, and more ecologically friendly production of silica and its nanoparticles from the ashes of agricultural wastes. The production of SiO2 nanoparticles (SiO2NPs) from different agricultural wastes, including rice husk, rice straw, maize cobs, and bagasse, was systematically and critically discussed. The review also emphasizes current issues and possibilities linked with contemporary technology to raise awareness and stimulate scholars' insight. Furthermore, the processes involved in isolating silica from agricultural wastes were explored in this work.


Assuntos
Nanopartículas , Oryza , Dióxido de Silício , Nanotecnologia , Agricultura/métodos
13.
Anal Methods ; 15(14): 1775-1789, 2023 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-36987853

RESUMO

An atmospheric pressure glow discharge (APGD) system, generated between a flowing liquid cathode (FLC) and a gas (He) jet anode, was applied for the determination of Zn, Mg, Ca, Na, and K in selected beverages commonly chosen by athletes (namely Coca-Cola Zero, energy and vitamin drinks, pre-workout, branched-chain amino acids, almond drink, and whey protein) by optical emission spectrometry (OES). In some cases (i.e., Coca-Cola, energy drink, and almond drink), sugared and sugar-free versions of the beverages were analyzed with the purpose of establishing the impact of added sugar on the analyte signal intensities. The analysis was performed after a simplified sample preparation procedure, which involved only their dilution and acidification with HNO3 to a concentration of 0.2 mol L-1. To determine the most suitable conditions for performing the analysis, optimization of the crucial operating parameters and sample dilution was carried out. Under the compromise conditions, the instrumental detection limits (DLs) were established and found to be 21, 0.91, 20, 0.062, and 0.14 µg L-1 for Zn, Mg, Ca, Na, and K, respectively. Due to the relatively low detection limits, the analyte content could be determined for a fairly high dilution, being concurrently the same for all analytes, which further simplified the whole procedure. It was found that the vast majority of samples could be determined using external calibration with simple standard solutions. The standard addition technique used for calibration was only required for the determination of Mg in three samples. The analysis results were consistent (in the majority of cases the recovery values were in the range of 88-111%) with the values obtained for the reference method (inductively coupled plasma optical emission spectrometry, ICP-OES), which proved the reliability of the results obtained from the developed FLC-APGD-OES system.


Assuntos
Sódio , Zinco , Humanos , Reprodutibilidade dos Testes , Análise Espectral/métodos , Íons , Bebidas , Eletrodos , Pressão Atmosférica , Atletas
14.
Microb Pathog ; 172: 105805, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36179974

RESUMO

Phyto-natural products are deeply associated with ethno-medicinal practices with less or more scientific validation for curing many vital diseases. Thus, the present study was carried out to asses chemical constituents and bioactivities of Grantia aucheri Boiss at different growth stages (vegetative, flowering, and seeding). For this aim, the chemical composition of G. aucheri ethanolic extracts was analyzed by gas chromatography with mass spectrometry detection (GC-MS), their total phenolics, total flavonoids, total tannins, and total anthocyanins concentrations were also spectrophotometrically determined. Antifungal and antibacterial activities were determined against three pathogenic fungi and six human pathogenic bacteria. Furthermore, antioxidant activity (DPPH and ABTS scavenging) and anti-inflammatory activity (Human Red Blood Cell Stabilization Method) were evaluated. The highest content of total phenolics, total flavonoids, total tannins, and total anthocyanins were established in the extract of G. aucheri at its flowering stage. Such phyto-compounds as boranyl acetate, ß-himachalene and himachalol were major compounds found among 34 chemical constituents identified. The best antioxidant, anti-inflammatory, antifungal, and antibacterial activities were also found for this extract. Its phytochemicals presented bactericidal activities, mainly against Staphylococcus aureus, Bacillus subtilis, and Streptococcus pyogenes along with moderate fungicidal activity, however, it was less effective than the first one. Apart from antioxidant, antimicrobial, and anti-inflammatory activities, chemical constituents of G. aucheri may be potential alternative biomedical applications to reduce synthetic chemicals drugs.


Assuntos
Anti-Infecciosos , Antioxidantes , Humanos , Antioxidantes/farmacologia , Antioxidantes/química , Antifúngicos/farmacologia , Antocianinas , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Compostos Fitoquímicos/química , Antibacterianos/farmacologia , Antibacterianos/química , Anti-Infecciosos/farmacologia , Anti-Infecciosos/química , Anti-Inflamatórios/farmacologia , Fenóis/farmacologia , Fenóis/análise , Taninos/farmacologia , Flavonoides/farmacologia , Flavonoides/análise
15.
Talanta ; 249: 123694, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-35738207

RESUMO

A technique of vapor generation assisted by a microplasma was used for sample introduction into inductively coupled plasma optical emission spectrometry (ICP OES). Replacing a pneumatic nebulizer with a novel microplasma device improved the sensitivities of analytical signals for Ag, Bi, Cd, Pb, Tl, and Zn (by 2-13 times), as well as a concomitant reduction in their detection limits (DLs). Moreover, an outstanding improvement (30-fold) was achieved for Hg. The factors contributing to the boosted signal intensities were higher analyte fluxes and less water vapor produced by the microplasma system. The DLs of Ag, Bi, Cd, Hg, Pb, Tl, and Zn in microplasma-ICP OES were 0.4, 4, 0.06, 0.2, 2, 5, and 0.2 µg L-1, respectively, and the measurement precision was within the range of 0.7-2.4% (it was significantly improved as compared to that achievable with pneumatic nebulization). The proposed microplasma-assisted vapor generation eliminates the use of toxic reductants, e.g., sodium tetrahydridoborate, and it is characterized by higher resistance to matrix effects from transition metal ions (as compared to chemical vapor generation (CVG) and photochemical vapor generation (PVG)). To validate the trueness of the SAGD-ICP OES method, certified reference materials of lobster hepatopancreas (TORT-2), cormorant tissue (MODAS-4) as well as spiked tap water and seawater samples were analyzed to determine levels Cd and Hg. The standard additions method was used for calibration in both cases. Recoveries of the analytes in the case of the analysis of TORT-2 and MODAS-4 samples as well as the spiked tap water and seawater was within the range of 98-113%, which indicated that the developed sample introduction system can be successfully used for very sensitive determinations of selected hazardous elements in environmental samples.


Assuntos
Cádmio , Mercúrio , Gases , Íons , Chumbo , Mercúrio/química , Análise Espectral , Tálio , Zinco
16.
Talanta ; 249: 123650, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-35688082

RESUMO

A new analytical method was proposed for multielement (Al, Ba, Ca, Cu, Fe, K, Mg, Mn, Na, Sr and Zn) analysis of Pu-erh teas infusions by inductively coupled plasma optical emission spectrometry. The Box-Behnken response surface design together with individual desirability functions and the joint desirability function approach was applied to develop experimental conditions of this new procedure, being alternative to high-temperature wet digestion. The procedure involved the samples to be just 5-fold diluted with 1.7 mol L-1 HNO3. The proposed method was precise (relative standard deviations within 2-8%), true (relative errors from -8 to +6%) and guaranteed very good detectability (detection limits within 1-6 ng g-1, except for Ca and Fe). It was used for analysis of infusions of Pu-erh teas as well as to verify the effect of their preparation conditions (steeping water temperature, steeping time).


Assuntos
Oligoelementos , Temperatura Alta , Íons/análise , Chá , Oligoelementos/análise
17.
Sci Rep ; 12(1): 7354, 2022 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-35513687

RESUMO

Doxycycline (DOX), an antibiotic commonly used in medicine and veterinary, is frequently detected in natural waterways. Exposition of bacteria to DOX residuals poses a selective pressure leading to a common occurrence of DOX-resistance genetic determinants among microorganisms, including virulent human pathogens. In view of diminishment of the available therapeutic options, we developed a continuous-flow reaction-discharge system generating pulse-modulated radio-frequency atmospheric pressure glow discharge (pm-rf-APGD) intended for DOX removal from liquid solutions. A Design of Experiment and a Response Surface Methodology were implemented in the optimisation procedure. The removal efficiency of DOX equalling 79 ± 4.5% and the resultant degradation products were identified by High-Performance Liquid Chromatography-Diode Array Detection, Liquid Chromatography Quadruple Time of Flight Mass Spectrometry, Ultraperformance Liquid Chromatography-Tandem Mass Spectrometry, total organic carbon, total nitrogen, Attenuated Total Reflectance Furrier Transform-Infrared, and UV/Vis-based methods. The pm-rf-APGD-treated DOX solution due to the generated Reactive Oxygen and Nitrogen Species either lost its antimicrobial properties towards Escherichia coli ATCC25922 or significantly decreased biocidal activities by 37% and 29% in relation to Staphylococcus haemolyticus ATCC29970 and Staphylococcus aureus ATCC25904, respectively. Future implementation of this efficient and eco-friendly antibiotic-degradation technology into wastewater purification systems is predicted.


Assuntos
Líquidos Corporais , Doxiciclina , Antibacterianos/farmacologia , Pressão Atmosférica , Doxiciclina/farmacologia , Escherichia coli , Humanos , Nitrogênio
18.
Talanta ; 246: 123500, 2022 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-35487012

RESUMO

A new technique of vapor generation assisted by a microplasma was proposed for an inductively coupled plasma mass spectrometry (ICP MS). It was found that, by replacing a traditional pneumatic nebulizer with a microplasma (solution anode glow discharge, SAGD), analytical signals of Ag, Bi, Cd, Hg, Pb, Tl, and Zn were improved 8, 4, 13, 13, 9, 10, and 7 times, respectively. The main factor contributing to boosted analytical signal intensities was the higher analyte flux produced by the novel microplasma system. The measurement precision in SAGD-ICP MS was comparable to that achievable for ICP MS (with pneumatic nebulization), and it did not exceed 2%. The detection limits of Ag, Bi, Cd, Hg, Pb, Tl, and Zn in SAGD-ICP MS were 5, 2, 6, 5, 4, 10, and 20 ng L-1, respectively. The analytical performance of this method may be further improved if the observed memory effects could be minimized. To validate the trueness of the novel method, certified reference materials of lobster hepatopancreas (TORT-2), cormorant tissue (MODAS-4), and wastewater (ERM CA-713) were analyzed to determine traces of Cd, Hg, and Pb. Recoveries of certified values for these analytes were ranged from 91 to 111%, which indicated that the studied microplasma system in combination with ICP MS can be successfully used for very sensitive determinations of selected hazardous elements in environmental samples.


Assuntos
Cádmio , Mercúrio , Cádmio/análise , Eletrodos , Gases , Chumbo , Espectrometria de Massas/métodos , Mercúrio/análise , Tálio , Zinco
19.
Molecules ; 27(5)2022 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-35268662

RESUMO

The aim of the present study was to investigate the changes in the content of phytochemical compounds and in vitro antioxidant, antibacterial, and anti-inflammatory activities of Teucrium polium L. aerial parts and root methanolic extracts at different phenological stages (vegetative, flowering, and seeding). The T. polium extracts were analyzed using gas chromatography−mass spectrometry (GC-MS), and their antioxidant properties were tested with the 2,2-diphenyl-1-picrylhydrazyl (DPPH), nitric oxide (NO), ferrous ions (Fe2+), and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid (ABTS) methods. Forty-nine compounds were identified with the majority of germacrene D, t-cadinol, ß-pinene, carvacrol, bicyclogermacrene, α-pinene, and limonene. The results show that the extracts significantly differ between different phenological stages of the plant material used in terms of the phytochemical composition (total phenolic compounds, total flavonoids, total alkaloids, and total saponin contents) and bioactivities (antioxidant, antibacterial, and anti-inflammatory) (p < 0.05). The highest total contents of phenolics (72.4 ± 2.5 mg gallic acid equivalent (GAE)/g dry weight), flavonoids (36.2 ± 3.1 mg quercetin equivalent (QE)/g dry weight), alkaloids (105.7 ± 2.8 mg atropine equivalent (AE)/g dry weight), and saponins (653 ± 6.2 mg escin equivalent (EE)/g dry weight), as well as antioxidant, antibacterial, and anti-inflammatory activities, were measured for the extract of the aerial parts obtained at the flowering stage. The minimum inhibitory concentration (MIC) values for the extracts were varied within 9.4−300 µg/mL, while the minimum bactericidal concentration (MBC) values were varied within 18.75−600 µg/mL. In addition, they were more active on Gram-positive bacteria than Gram-negative bacteria. The data of this work confirm that the T. polium extracts have significant biological activity and hence can be used in the pharmaceutical industry, clinical applications, and medical research, as well as cosmetic and food industries.


Assuntos
Compostos Fitoquímicos
20.
Food Chem ; 377: 131903, 2022 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-34990952

RESUMO

We proposed an innovative and economic method for rapid production of functionalized orange juice (OJ) with excellent nutritional properties, prolonged shelf life, and safe consumption. To reach this goal, we have employed direct current atmospheric pressure glow discharge, generated in contact with a flowing liquid cathode (FLC-dc-APGD) in a highly-throughput reaction-discharge system. It was found that controlled FLC-dc-APGD-treatment of OJ lead to increase the concentration of selected metals and phenolic compounds. The so-obtained OJ had the same qualitative composition of fragrance as the untreated one, however, its shelf life was prolonged up to 26 days. Furthermore, OJ exposed to FLC-dc-APGD-treatment did not exhibit any cytotoxic properties towards non-malignant human intestinal epithelial cell lines. On the other hand, the induction of cell cytotoxicity was observed in human colorectal adenocarcinoma cells line after FLC-dc-APGD-treated OJ application. We truly believe that produced by us functionalized OJ might be a tempting alternative to classic, non-treated by FLC-dc-APGD OJ.


Assuntos
Líquidos Corporais , Citrus sinensis , Pressão Atmosférica , Sucos de Frutas e Vegetais , Humanos , Fenóis
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