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1.
Int J Mol Sci ; 25(8)2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38673798

RESUMO

The present work aims to study the possibilities of developing silver nanoparticles using natural extracts of grape pomace wastes originating from the native variety of Feteasca Neagra 6 Șt. This study focused on investigating the influence of grape pomace extract obtained by two different extraction methods (classical temperature extraction and microwave-assisted extraction) in the phytosynthesis process of metal nanoparticles. The total phenolic content of the extracts was assessed using the spectrophotometric method with the Folin-Ciocâlteu reagent, while the identification and quantification of specific components were conducted through high-performance liquid chromatography with a diode array detector (HPLC-DAD). The obtained nanoparticles were characterized by UV-Vis absorption spectroscopy, X-ray diffraction (XRD), and transmission electron microscopy (TEM), along with assessing their antioxidant and antimicrobial properties against Gram-positive bacteria. The data collected from the experiments indicated that the nanoparticles were formed in a relatively short period of time (96 h) and, for the experimental variant involving the use of a 1:1 ratio (v/v, grape pomace extract: silver nitrate) for the nanoparticle phytosynthesis, the smallest crystallite sizes (from X-ray diffraction-4.58 nm and 5.14 nm) as well as spherical or semispherical nanoparticles with the lowest average diameters were obtained (19.99-23 nm, from TEM analysis). The phytosynthesis process was shown to enhance the antioxidant properties (determined using the DPPH assay) and the antimicrobial potential (tested against Gram-positive strains) of the nanoparticles, as evidenced by comparing their properties with those of the parent extracts; at the same time, the nanoparticles exhibited a selectivity in action, being active against the Staphylococcus aureus strain while presenting no antimicrobial potential against the Enterococcus faecalis strain.


Assuntos
Antioxidantes , Química Verde , Nanopartículas Metálicas , Extratos Vegetais , Prata , Vitis , Vitis/química , Nanopartículas Metálicas/química , Prata/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Antioxidantes/farmacologia , Antioxidantes/química , Química Verde/métodos , Anti-Infecciosos/farmacologia , Anti-Infecciosos/química , Testes de Sensibilidade Microbiana , Antibacterianos/farmacologia , Antibacterianos/química , Antibacterianos/síntese química , Difração de Raios X
2.
Int J Mol Sci ; 22(4)2021 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-33546333

RESUMO

Natural compounds obtained from different medicinal and aromatic plants have gained respect as alternative treatments to synthetic drugs, as well as raw materials for different applications (cosmetic, food and feed industries, environment protection, and many others). Based on a literature survey on dedicated databases, the aim of the present work is to be a critical discussion of aspects regarding classical extraction versus modern extraction techniques; possibilities to scale up (advantages and disadvantages of different extraction methods usually applied and the influence of extraction parameters); and different medicinal and aromatic plants' different applications (medical and industrial applications, as well as the potential use in nanotechnology). As nowadays, research studies are directed toward the development of modern, innovative applications of the medicinal and aromatic plants, aspects regarding future perspectives are also discussed.


Assuntos
Compostos Fitoquímicos/farmacologia , Plantas Medicinais/química , Animais , Humanos , Nanotecnologia , Compostos Fitoquímicos/uso terapêutico
3.
Molecules ; 25(3)2020 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-31979351

RESUMO

The strawberries represent in our days one of the main fresh fruits consumed globally, inevitably leading to large amounts of by-products and wastes. Usually appreciated because of their specific flavor, the strawberries also possess biological properties, including antioxidant, antimicrobial, or anti-inflammatory effects. In spite of the wide spread of the Fragaria genus, few species represent the subject of the last decade scientific research. The main components identified in the Fragaria species are presented, as well as several biological properties, as emerging from the scientific papers published in the last decade.


Assuntos
Anti-Infecciosos/química , Anti-Inflamatórios/química , Antioxidantes/química , Fragaria/química , Fragaria/metabolismo , Antocianinas/análise , Flavonóis/análise , Hidroxibenzoatos/análise , Fenóis/análise , Paladar , Vitaminas/análise
4.
Molecules ; 25(2)2020 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-31940923

RESUMO

Continuously growing demand for plant derived therapeutic molecules obtained in a sustainable and eco-friendly manner favors biotechnological production and development of innovative extraction techniques to obtain phytoconstituents. What is more, improving and optimization of alternative techniques for the isolation of high value natural compounds are issues having both social and economic importance. In this critical review, the aspects regarding plant biotechnology and green downstream processing, leading to the production and extraction of increased levels of fine chemicals from both plant cell, tissue, and organ culture or fresh plant materials and the remaining by-products, are discussed.


Assuntos
Biotecnologia/métodos , Cromatografia/métodos , Extração Líquido-Líquido/métodos , Compostos Fitoquímicos/isolamento & purificação , Extração em Fase Sólida/métodos , Apiaceae/química , Asteraceae/química , Biotecnologia/instrumentação , Biotecnologia/tendências , Cromatografia/instrumentação , Fabaceae/química , Humanos , Lamiaceae/química , Micro-Ondas , Myrtaceae/química , Compostos Fitoquímicos/química , Células Vegetais/química , Plantas Medicinais , Sonicação/métodos
5.
Molecules ; 24(23)2019 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-31757027

RESUMO

Large amounts of agro-industrial waste are being generated each year, leading to pollution and economic loss. At the same time, these side streams are rich source of active compounds including antioxidants. Recovered compounds can be re-utilized as food additives, functional foods, nutra-/pharmaceuticals, cosmeceuticals, beauty products, and bio-packaging. Advanced extraction techniques are promising tools to recover target compounds such as antioxidants from agro-industrial side streams. Due to the disadvantages of classical extraction techniques (such as large amounts of solvents, increased time of extraction, large amounts of remaining waste after the extraction procedure, etc.), and advanced techniques emerged, in order to obtain more efficient and sustainable processes. In this review paper aspects regarding different modern extraction techniques related to recovery of antioxidant compounds from wastes generated in different industries and their applications are briefly discussed.


Assuntos
Agricultura , Antioxidantes , Cosmecêuticos , Resíduos Industriais , Antioxidantes/química , Antioxidantes/isolamento & purificação , Cosmecêuticos/química , Cosmecêuticos/isolamento & purificação
6.
Molecules ; 24(19)2019 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-31547052

RESUMO

Catalysis represents the cornerstone of chemistry, since catalytic processes are ubiquitous in almost all chemical processes developed for obtaining consumer goods. Nanocatalysis represents nowadays an innovative approach to obtain better properties for the catalysts: stable activity, good selectivity, easy to recover, and the possibility to be reused. Over the last few years, for the obtaining of new catalysts, classical methods-based on potential hazardous reagents-have been replaced with new methods emerged by replacing those reagents with plant extracts obtained in different conditions. Due to being diversified in morphology and chemical composition, these materials have different properties and applications, representing a promising area of research. In this context, the present review focuses on the metallic nanocatalysts' importance, different methods of synthesis with emphasis to the natural compounds used as support, characterization techniques, parameters involved in tailoring the composition, size and shape of nanoparticles and applications in catalysis. This review presents some examples of green nanocatalysts, grouped considering their nature (mono- and bi-metallic nanoparticles, metallic oxides, sulfides, chlorides, and other complex catalysts).


Assuntos
Nanopartículas Metálicas/química , Catálise , Cloretos/química , Química Verde , Óxidos/química , Tamanho da Partícula , Sulfetos/química
7.
BMC Complement Altern Med ; 18(1): 3, 2018 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-29301523

RESUMO

BACKGROUND: Juniperus communis L. represents a multi-purpose crop used in the pharmaceutical, food, and cosmetic industry. Several studies present the possible medicinal properties of different Juniperus taxa native to specific geographical area. The present study aims to evaluate the genoprotective, antioxidant, antifungal and anti-inflammatory potential of hydroalcoholic extract of wild-growing Juniperus communis L. (Cupressaceae) native to Romanian southern sub-Carpathian hills. METHODS: The prepared hydroethanolic extract of Juniperus communis L. was characterized by GC-MS, HPLC, UV-Vis spectrometry and phytochemical assays. The antioxidant potential was evaluated using the DPPH assay, the antifungal effect was studied on Aspergillus niger ATCC 15475 and Penicillium hirsutum ATCC 52323, while the genoprotective effect was evaluated using the Allium cepa assay. The anti-inflammatory effect was evaluated in two inflammation experimental models (dextran and kaolin) by plethysmometry. Male Wistar rats were treated by gavage with distilled water (negative control), the microemulsion (positive control), diclofenac sodium aqueous solution (reference) and microemulsions containing juniper extract (experimental group). The initial paw volume and the paw volumes at 1, 2, 3, 4, 5 and 24 h were measured. RESULTS: Total terpenoids, phenolics and flavonoids were estimated to be 13.44 ± 0.14 mg linalool equivalent, 19.23 ± 1.32 mg gallic acid equivalent, and 5109.6 ± 21.47 mg rutin equivalent per 100 g of extract, respectively. GC-MS characterization of the juniper extract identified 57 volatile compounds in the sample, while the HPLC analysis revealed the presence of the selected compounds (α-pinene, chlorogenic acid, rutin, apigenin, quercitin). The antioxidant potential of the crude extract was found to be 81.63 ± 0.38% (measured by the DPPH method). The results of the antifungal activity assay (for Aspergillus niger and Penicillium hirsutum) were 21.6 mm, respectively 17.2 mm as inhibition zone. Test results demonstrated the genoprotective potential of J. communis undiluted extract, inhibiting the mitodepressive effect of ethanol. The anti-inflammatory action of the juniper extract, administered as microemulsion in acute-dextran model was increased when compared to kaolin subacute inflammation induced model. CONCLUSION: The hydroalcoholic extract obtained from wild-growing Juniperus communis native to Romanian southern sub-Carpathian hills has genoprotective, antioxidant, antifungal and anti-inflammatory properties.


Assuntos
Anti-Inflamatórios/farmacologia , Antifúngicos/farmacologia , Juniperus/química , Extratos Vegetais/farmacologia , Substâncias Protetoras/farmacologia , Animais , Anti-Inflamatórios/química , Antifúngicos/química , Aspergillus niger/efeitos dos fármacos , Compostos de Bifenilo/análise , Compostos de Bifenilo/metabolismo , Flavonoides/química , Flavonoides/farmacologia , Inflamação/metabolismo , Masculino , Penicillium/efeitos dos fármacos , Fenóis/química , Fenóis/farmacologia , Picratos/análise , Picratos/metabolismo , Extratos Vegetais/química , Substâncias Protetoras/química , Ratos , Ratos Wistar , Romênia
8.
Molecules ; 23(10)2018 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-30257512

RESUMO

Satureja hortensis L. (summer savory) is an annual herbaceous crop, native to Europe and in our days spread and used all over the world. Although its use as spice and medicinal plant is known since ancient times, peer-reviewed studies presenting the scientific data are scarce. The natural products obtained from summer savory (extracts and essential oil) are dominated by polyphenols and flavonoids, responsible for their antioxidant, antimicrobial, antiparasitic, pesticidal, anti-inflammatory, analgesic, hepatoprotective and anticancer properties, among others. The current study presents the progress made in the last decade regarding the potential applications of summer savory, being the first review study focused on S. hortensis, in the same time suggesting future research opportunities, as they appear from the properties of other Satureja species. The available data presenting the properties of summer savory represents a scientific support for application in industry, for developing "clean label" food products.


Assuntos
Antioxidantes/química , Compostos Fitoquímicos/química , Extratos Vegetais/química , Satureja/química , Analgésicos/química , Analgésicos/uso terapêutico , Antibacterianos/química , Antibacterianos/uso terapêutico , Anti-Infecciosos/química , Anti-Infecciosos/uso terapêutico , Humanos , Óleos Voláteis/química , Compostos Fitoquímicos/uso terapêutico , Extratos Vegetais/uso terapêutico , Polifenóis/química , Polifenóis/uso terapêutico
9.
Bull Environ Contam Toxicol ; 100(3): 438-443, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29335756

RESUMO

The paper aims to determine the lead-induced physiological, biochemical and enzymatic changes in Asplenium scolopendrium, which could represent biomarkers used in environmental assessment. Of all the physiological processes, photosynthesis and respiration were analyzed and the enzymatic and biochemical determinations focused on catalase activity, assimilatory pigment concentration, polyphenol content and lead presence in tissues.The stress induced by the exposure to Pb of the species Asplenium scolopendrium determined an increase in the carotenoid content, the catalase activity, the total polyphenol content and also enhanced the respiration potential. No significant changes were recorded regarding the chlorophyll content and the photosynthetic activity. The recorded changes may be used as non-specific markers in the assessment of the impact of Pb on plants (Asplenium scolopendrium).


Assuntos
Carotenoides/metabolismo , Catalase/metabolismo , Monitoramento Ambiental/métodos , Chumbo/toxicidade , Polifenóis/metabolismo , Poluentes do Solo/toxicidade , Traqueófitas/efeitos dos fármacos , Biomarcadores/metabolismo , Clorofila/metabolismo , Chumbo/análise , Fotossíntese/efeitos dos fármacos , Romênia , Poluentes do Solo/análise , Traqueófitas/crescimento & desenvolvimento , Traqueófitas/metabolismo
10.
Bull Environ Contam Toxicol ; 100(3): 376-383, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29368302

RESUMO

The objective of the study is to screen for morphological, biochemical and histological changes induced by six widely used pesticides (Reldan 40EC, Actara 25WG, Tilt 250EC, Champion 50WG, Fusilade Forte, Dual Gold 960EC) in the amphibian species Pelophylax ridibundus (Pallas, 1771). Highly degenerative changes were observed in animals cultured at 22-24°C, compared to those cultured at 4-6°C. The hepatosomatic index increased upon exposure to almost all of the pesticides, the erythrocyte number decreased upon exposure to all pesticides except Reldan 40EC, while leucopenia was observed only for Reldan 40EC and Actara 25WG. Hyperglycemia was observed upon administration of pesticides (except Champion 50WG and Fusilade Forte, for which hypoglycemia is registered), while a decrease in cholesterol levels was induced by nearly all pesticides. Triglycerides varied only slightly. The results suggest that chronic pesticides exposure can lead to alteration of various indices, as well as to hepatic lesions in amphibians.


Assuntos
Monitoramento Ambiental/métodos , Praguicidas/toxicidade , Ranidae/fisiologia , Poluentes Químicos da Água/toxicidade , Animais , Glicemia/análise , Eritrócitos/citologia , Feminino , Leucócitos/citologia , Masculino , Ranidae/sangue , Romênia , Estações do Ano
11.
Bull Environ Contam Toxicol ; 97(2): 203-10, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27207230

RESUMO

The aim of the study was to investigate the protective role of thiourea on the physiological, hematological, biochemical and histopathological parameters of Leuciscus cephalus exposed to sublethal concentration of Pendigan 330 EC herbicide. The animals were divided in four experimental groups (control, animals subjected to 1 ‰ thiourea, animals subjected to 4 × 10(-4) mL/L herbicide and, respectively, animals subjected to 4 × 10(-4) mL/L herbicide and 1 ‰ thiourea). Exposure of European chub to herbicide administered in water for 2 weeks determined installation of pathological changes in the liver and gills tissues. Also, were observed a decrease in the number of white blood cells and oxygen consumption, breathing frequency, and an increase in the number of red blood cells and glycaemia values. Thiourea counteracts the toxic action, describing itself as normal liver parenchyma and normal gills in animals intoxicated with herbicide, without lesion, and a return to normal values of the studied markers.


Assuntos
Compostos de Anilina/toxicidade , Cyprinidae/fisiologia , Herbicidas/toxicidade , Substâncias Protetoras/farmacologia , Tioureia/farmacologia , Poluentes Químicos da Água/toxicidade , Animais , Biomarcadores/metabolismo , Brânquias/patologia , Fígado/química , Testes de Toxicidade Subaguda , Poluentes Químicos da Água/análise
12.
Materials (Basel) ; 17(11)2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38893756

RESUMO

This work aims to evaluate the potential use of natural wastes (in particular, clam shells) to synthesize one of the most well-known and versatile materials from the phosphate mineral group, hydroxyapatite (HAP). The obtained material was characterized in terms of morphology and composition using several analytical methods (scanning electron microscopy-SEM, X-ray diffraction-XRD, X-ray fluorescence-XRF, Fourier transform infrared spectroscopy-FTIR, thermal analysis-TGA, and evaluation of the porosity and specific surface characteristics by the Brunauer-Emmett-Teller-BET method) in order to confirm the successful synthesis of the material and to evaluate the presence of potential secondary phases. The developed material was further doped with iron oxide (HAP-Fe) using a microwave-assisted method, and both materials were evaluated in terms of photocatalytic activity determined by the photodecomposition of methylene blue (MB) which served as a contaminant model. The best results (approx. 33% MB degradation efficiency, after 120 min. of exposure) were obtained for the hydroxyapatite material, superior to the HAP-Fe composite (approx. 27%). The utilization of hydroxyapatite obtained from clam shells underscores the importance of sustainable and eco-friendly practices in materials syntheses. By repurposing waste materials from the seafood industry, we not only reduce environmental impact, but also create a valuable resource with diverse applications, contributing to advancements in both healthcare and environmental protection.

13.
Plants (Basel) ; 13(3)2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38337867

RESUMO

Nanotechnology can offer a series of new "green" and eco-friendly methods for developing different types of nanoparticles, among which the development of nanomaterials using plant extracts (phytosynthesis) represents one of the most promising areas of research. This present study details the use of lavender flowers (Lavandula angustifolia Mill., well-known for their use in homeopathic applications) for the biosynthesis of silver nanoparticles with enhanced antioxidant and antibacterial properties. Several qualitative and quantitative assays were carried out in order to offer an image of the extracts' composition (the recorded total phenolics content varied between 21.0 to 40.9 mg GAE (gallic acid equivalents)/g dry weight (d.w.), while the total flavonoids content ranged between 3.57 and 16.8 mg CE (catechin equivalents)/g d.w.), alongside modern analytical methods (such as gas chromatography-mass spectrometry-GC-MS, quantifying 12 phytoconstituents present in the extracts). The formation of silver nanoparticles (AgNPs) using lavender extract was studied by UV-Vis spectroscopy, Fourier-transform infrared spectrometry (FTIR), scanning electron microscopy (SEM), X-ray diffraction (XRD), and dynamic light scattering (DLS)/zeta potential, with the selected nanoparticles having crystallite sizes of approx. 14.55 nm (AgNP-L2) and 4.61 nm, respectively (for AgNP-L4), and hydrodynamic diameters of 392.4 nm (for AgNP-L2) and 391.6 nm (for AgNP-L4), determined by DLS. A zeta potential of around -6.4 mV was displayed for both samples while presenting as large aggregates, in which nanoparticle clusters with dimensions of around 130-200 nm can be observed. The biomedical applications of the extracts and the corresponding phytosynthesized nanoparticles were evaluated using antioxidant and antimicrobial assays. The obtained results confirmed the phytosynthesis of the silver nanoparticles using Lavandula angustifolia Mill. extracts, as well as their antioxidant and antimicrobial potential.

14.
Polymers (Basel) ; 16(10)2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38794562

RESUMO

Nosocomial infections represent a major threat within healthcare systems worldwide, underscoring the critical need for materials with antimicrobial properties. This study presents the development of polyurethane foam embedded with silver nanoparticles (PUF/AgNPs) using a rapid, eco-friendly, in situ radiochemical synthesis method. The nanocomposites were characterized by UV-vis and FTIR spectroscopy, scanning electron microscopy coupled with energy dispersive X-ray technique (SEM/EDX), differential scanning calorimetry (DSC), dynamic mechanical analysis (DMA), tensile and compression strengths, antimicrobial activity, and foam toxicity tests. The resulting PUF/AgNPs demonstrated prolonged stability (over 12 months) and good dispersion of AgNPs. Also, the samples presented higher levels of hardness compared to samples without AgNPs (deformation of 1682 µm for V1 vs. 4307 µm for V0, under a 5 N force), tensile and compression strength of 1.80 MPa and 0.34 Mpa, respectively. Importantly, they exhibited potent antimicrobial activity against a broad range of bacteria (including Pseudomonas aeruginosa, Staphylococcus aureus, Escherichia coli, and Enterococcus faecalis) and a fungal mixture (no fungal growth on the sample surface was observed after 28 days of exposure). Furthermore, these materials were non-toxic to human keratinocytes, which kept their specific morphology after 24 h of incubation, highlighting their potential for safe use in biomedical applications. We envision promising applications for PUF/AgNPs in hospital bed mattresses and antimicrobial mats, offering a practical strategy to reduce nosocomial infections and enhance patient safety within healthcare facilities.

15.
Plants (Basel) ; 13(7)2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38611526

RESUMO

Hyssop (Hyssopus officinalis L.) and oregano (Origanum vulgare L.), traditionally used for their antimicrobial properties, can be considered viable candidates for nanotechnology applications, in particular for the phytosynthesis of metal nanoparticles. The present work aims to evaluate the potential application of hyssop and oregano for the phytosynthesis of silver nanoparticles, as well as to evaluate the biological activities of their extracts and obtained nanoparticles (antioxidant potential, as well as cell viability, inflammation level and cytotoxicity in human fibroblasts HFIB-G cell line studies). In order to obtain natural extracts, two extraction methods were applied (classical temperature extraction and microwave-assisted extraction), with the extraction method having a major influence on their composition, as demonstrated by both the total phenolic compounds (significantly higher for the microwave-assisted extraction; the oregano extracts had consistently higher TPC values, compared with the hyssop extracts) and in terms of individual components identified via HPLC. The obtained nanoparticles ware characterized via X-ray diffraction (XRD) and transmission electron microscopy (TEM), with the lowest dimension nanoparticles being recorded for the nanoparticles obtained using the oregano microwave extract (crystallite size 2.94 nm through XRD, average diameter 10 nm via TEM). The extract composition and particle size also influenced the antioxidant properties (over 60% DPPH inhibition being recorded for the NPs obtained using the oregano microwave extract). Cell viability was not affected at the lowest tested concentrations, which can be correlated with the nitric oxide level. Cell membrane integrity was not affected after exposure to classic temperature hyssop extract-NPs, while the other samples led to a significant LDH increase.

16.
Nanomaterials (Basel) ; 14(10)2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38786851

RESUMO

Metal nanoparticle phytosynthesis has become, in recent decades, one of the most promising alternatives for the development of nanomaterials using "green chemistry" methods. The present work describes, for the first time in the literature, the phytosynthesis of silver nanoparticles (AgNPs) using extracts obtained by two methods using the aerial parts of Marrubium vulgare L. The extracts (obtained by classical temperature extraction and microwave-assisted extraction) were characterized in terms of total phenolics content and by HPLC analysis, while the phytosynthesis process was confirmed using X-ray diffraction and transmission electron microscopy, the results suggesting that the classical method led to the obtaining of smaller-dimension AgNPs (average diameter under 15 nm by TEM). In terms of biological properties, the study confirmed that AgNPs as well as the M. vulgare crude extracts reduced the viability of human gingival fibroblasts in a concentration- and time-dependent manner, with microwave-assisted extracts having the more pronounced effects. Additionally, the study unveiled that AgNPs transiently increased nitric oxide levels which then decreased over time, thus offering valuable insights into their potential therapeutic use and safety profile.

17.
Nanomaterials (Basel) ; 13(5)2023 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-36903714

RESUMO

In the last decade, researchers have focused on the recycling of agro-food wastes for the production of value-added products. This eco-friendly trend is also observed in nanotechnology, where recycled raw materials may be processed into valuable nanomaterials with practical applications. Regarding environmental safety, replacing hazardous chemical substances with natural products obtained from plant wastes is an excellent opportunity for the "green synthesis" of nanomaterials. This paper aims to critically discuss plant waste, with particular emphasis on grape waste, methods of recovery of active compounds, and nanomaterials obtained from by-products, along with their versatile applications, including healthcare uses. Moreover, the challenges that may appear in this field, as well as future perspectives, are also included.

18.
Polymers (Basel) ; 15(9)2023 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-37177209

RESUMO

Anthropogenic activities lead to the issue of new classes of pollutants in the environment that are not currently monitored in environmental studies. This category of pollutants (known as emerging contaminants) includes a very wide range of target substances, such as pharmaceuticals, plant protection products, personal care products, dyes, toxins, microplastics and many other industrially important intermediaries. Together with an increasing demand for clean water (both for agricultural necessities and for the increasing population consumption), the need for the removal of emerging pollutants, simultaneously with the current "green chemistry" approach, opens the door for the industrial application of natural polymers in the area of environmental protection. Recent developments in this area are presented in this paper, as well as the application of these particular natural materials for the removal of other contaminants of interest (such as radioisotopes and nanoparticles). The current knowledge regarding the processes' kinetics is briefly presented, as well as the future development perspectives in this area.

19.
Materials (Basel) ; 16(7)2023 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-37049167

RESUMO

The continuous degradation of cultural heritage artifacts (due to different factors, including the rising air pollution, climate change or excessive biological activity, among others) requires the continuous development of protection strategies, technologies and materials. In this regard, polyelectrolytes have offered effective ways to fight against degradation but also to conserve the cultural heritage objects. In this review, we highlight the key developments in the creation and use of polyelectrolytes for the preservation, consolidation and cleaning of the cultural heritage artifacts (with particular focus on stone, metal and artifacts of organic nature, such as paper, leather, wood or textile). The state of the art in this area is presented, as well as future development perspectives.

20.
Materials (Basel) ; 16(9)2023 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-37176353

RESUMO

The present work describes, for the first time in the literature, the phytosynthesis of silver nanoparticles using Leonurus cardiaca L. extracts. The influence of the extraction method (classical temperature extraction and microwave extraction), as well as of the extract concentration on the characteristics of the nanoparticles, was studied using analytical methods, such as UV-Vis spectrometry, X-ray diffraction, dynamic light scattering, and transmission electron microscopy. Experimental data suggest that use of lower extract concentration leads to smaller dimensions nanoparticles, the same effect using the extract obtained by microwave-assisted extraction. The smallest recorded crystallite sizes (by X-ray diffraction) were under 3 nm. The antioxidant properties (determined by the DPPH assay) and the antimicrobial potential (determined against Gram-negative and Gram-positive strains) are enhanced by the phytosynthesis process (as demonstrated by the comparison of the nanoparticles' properties with the parent extracts). The present work could also represent an important step in obtaining nanoparticles with enhanced properties and controlled morphologies, but also offers information on the phytosynthesis of metallic nanoparticles using low extract concentrations.

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