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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 ; 23(19)2022 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-36232763

RESUMO

Biodeterioration of cultural heritage is caused by different organisms capable of inducing complex alteration processes. The present study aimed to evaluate the efficiency of Rosmarinus officinalis hydro-alcoholic extract to inhibit the growth of deteriogenic microbial strains. For this, the physico-chemical characterization of the vegetal extract by UHPLC-MS/MS, its antimicrobial and antibiofilm activity on a representative number of biodeteriogenic microbial strains, as well as the antioxidant activity determined by DPPH, CUPRAC, FRAP, TEAC methods, were performed. The extract had a total phenol content of 15.62 ± 0.97 mg GAE/mL of which approximately 8.53% were flavonoids. The polyphenolic profile included carnosic acid, carnosol, rosmarinic acid and hesperidin as major components. The extract exhibited good and wide spectrum antimicrobial activity, with low MIC (minimal inhibitory concentration) values against fungal strains such as Aspergillus clavatus (MIC = 1.2 mg/mL) and bacterial strains such as Arthrobacter globiformis (MIC = 0.78 mg/mL) or Bacillus cereus (MIC = 1.56 mg/mL). The rosemary extract inhibited the adherence capacity to the inert substrate of Penicillium chrysogenum strains isolated from wooden objects or textiles and B. thuringiensis strains. A potential mechanism of R. officinalis antimicrobial activity could be represented by the release of nitric oxide (NO), a universal signalling molecule for stress management. Moreover, the treatment of microbial cultures with subinhibitory concentrations has modulated the production of microbial enzymes and organic acids involved in biodeterioration, with the effect depending on the studied microbial strain, isolation source and the tested soluble factor. This paper reports for the first time the potential of R. officinalis hydro-alcoholic extract for the development of eco-friendly solutions dedicated to the conservation/safeguarding of tangible cultural heritage.


Assuntos
Anti-Infecciosos , Hesperidina , Rosmarinus , Anti-Infecciosos/farmacologia , Antioxidantes/farmacologia , Flavonoides/farmacologia , Óxido Nítrico , Fenóis/farmacologia , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Rosmarinus/química , Espectrometria de Massas em Tandem
3.
Molecules ; 27(12)2022 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-35744970

RESUMO

Pomegranate variety properties are important not only to demonstrate their diversity but also to satisfy the current market need for high-quality fruits. This study aims to characterize pomological and physico-chemical features as well as the antioxidant capacity of Moroccan local cultivars (Djeibi, Mersi, Sefri 1 and Sefri 2) compared to the imported ones (Mollar de Elche and Hicaz). The pomological characteristics of varieties were relatively diverse. The juice varieties (PJ) displayed a marketed variability in organoleptic and quality properties, such as the flavor, juice yield, and micro/macronutrients contents. Interrelationships among the analyzed properties and PJ varieties were investigated by principal component analysis (PCA). Dimension of the data set was reduced to two components by PCA accounting for 64.53% of the variability observed. The rinds varieties (PR) were studied for their total phenolics, flavonoids, and condensed tannins quantifications. PR varieties extracts exhibited different levels of free radical scavenging activity and local varieties revealed a greater potential with stability over time. The HPLC-DAD analyses of PR extracts revealed (+) catechin as the major compound, where the highest content was found for the local varieties. The SEC analysis showed the molecular weight distribution of phenolic compounds with a high size of condensed tannins formed by the polymerization of the catechin monomer. Given these properties, this research provides an easy selection of high-quality fruits as potential candidates for local market needs.


Assuntos
Catequina , Lythraceae , Punica granatum , Proantocianidinas , Antioxidantes/química , Catequina/análise , Frutas/química , Lythraceae/química , Marrocos , Fenóis/análise , Extratos Vegetais/química , Proantocianidinas/análise , Sensação
4.
Molecules ; 25(17)2020 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-32854362

RESUMO

Plant extracts are highly valuable pharmaceutical complexes recognized for their biological properties, including antibacterial, antifungal, antiviral, antioxidant, anticancer, and anti-inflammatory properties. However, their use is limited by their low water solubility and physicochemical stability. In order to overcome these limitations, we aimed to develop nanostructured carriers as delivery systems for plant extracts; in particular, we selected the extract of Anthriscus sylvestris (AN) on the basis of its antimicrobial effect and antitumor activity. In this study, AN-extract-functionalized magnetite (Fe3O4@AN) nanoparticles (NPs) were prepared by the co-precipitation method. The purpose of this study was to synthesize and investigate the physicochemical and biological features of composite coatings based on Fe3O4@AN NPs obtained by matrix-assisted pulsed laser evaporation technique. In this respect, laser fluence and drop-casting studies on coatings were performed. The physical and chemical properties of laser-synthesized coatings were investigated by scanning electron microscopy, while Fourier transform infrared spectroscopy comparative analysis was used for determining the chemical structure and functional integrity. Relevant data regarding the presence of magnetic nanoparticles as the only crystalline phase and the size of nanoparticles were obtained by transmission electron microscopy. The in vitro toxicity assessment of the Fe3O4@AN showed significant cytotoxic activity against human adenocarcinoma HT-29 cells after prolonged exposure. Antimicrobial results demonstrated that Fe3O4@AN coatings inhibit microbial colonization and biofilm formation in clinically relevant bacteria species and yeasts. Such coatings are useful, natural, and multifunctional solutions for the development of tailored medical devices and surfaces.


Assuntos
Adenocarcinoma/tratamento farmacológico , Anti-Infecciosos , Antineoplásicos Fitogênicos , Apiaceae/química , Materiais Revestidos Biocompatíveis , Nanopartículas de Magnetita , Extratos Vegetais , Adenocarcinoma/metabolismo , Adenocarcinoma/patologia , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Materiais Revestidos Biocompatíveis/química , Materiais Revestidos Biocompatíveis/farmacologia , Células HT29 , Humanos , Nanopartículas de Magnetita/química , Nanopartículas de Magnetita/uso terapêutico , Extratos Vegetais/química , Extratos Vegetais/farmacologia
5.
Molecules ; 25(19)2020 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-33036369

RESUMO

Basil (Ocimum spp.) is a traditional herbal medicine abundant in antioxidants such as phenolic compounds. As part of a diet, this herb is proved to have some roles in decreasing the risk of cancer, and in the treatment of inflammation and neurodegenerative diseases. This study aims to explore the total phenolic and flavonoid content of two new basil hybrids growing in Romania, namely "Aromat de Buzau" (AB) and "Macedon" (MB). The antioxidant capacity of those two species was also analyzed by DPPH and cyclic voltammetry. Six different flavonoids, such as catechin (+), rutin, hyperoside, naringin, naringenin, and genistein, were separated, identified, and quantified by HPLC-DAD chromatography, for the first time, from romanian basil hybrids. The main flavonoid of the extracts was found to be naringin which is present in the highest amount (26.18 mg/kg) in "Aromat de Buzau" (O. basilicum) methanolic extract. These results suggest that dietary intake of these new hybrids can be a source of antioxidant compounds.


Assuntos
Flavonoides/análise , Ocimum basilicum/química , Antioxidantes/análise , Quimera , Cromatografia Líquida de Alta Pressão
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.
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
8.
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
9.
ACS Omega ; 9(25): 27428-27437, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38947794

RESUMO

Recently, obtaining collagen films using a cross-linking technique has been a successful strategy. The current investigation used six cross-linker extracts (CE) from six different pomegranate varieties' byproducts to make and characterize collagen-tannin films using acid-soluble collagen (SC). The polymeric film has a yellow hue after CE incorporation. Fourier transform infrared spectroscopy assessed the impact of CE and its successful interaction within the matrix. The shifts verify different interactions between extracts and collagen functional groups, where they likely form new hydrogen bonds, retaining their helix structure without damaging the matrix. Scanning electron microscopy was used to analyze the morphology and fiber size. The average diameter of the fibers was found to be about 3.64 µm. Thermal behaviors (denaturation and degradation) were investigated by thermogravimetric analysis. The weight losses of cross-linked films increased by around 20% compared to non-cross-linked ones. This phenomenon was explained by the absence of telopeptide sections in the collagen helical structure, typically reinforced by lysine and hydroxylysine covalent linkages. Nanoscaled observations were also accomplished using transmission electron microscopy (TEM) on SC and SC-CE. The TEM analysis confirmed the CE polymerization degree effect on the cross-linking density via the overlap sequences, ranging up to 32.38 ± 2.37 nm on the fibril. The prepared biodegradable collagen-tannin film showed higher cross-linking density, which is expected to improve the biomaterial applications of collagen films while exploiting the underrated pomegranate byproducts.

10.
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.

11.
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.

12.
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.

13.
Antioxidants (Basel) ; 12(12)2023 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-38136246

RESUMO

The aims of the present study were to evaluate for the first time the chemical composition and antioxidant, antibacterial, antifungal and antiproliferative potentials of the Romanian George 90 lavender species, as well as parental species, L. angustifolia and L. latifolia. The L. angustifolia, L. latifolia and George 90 essential oils were analyzed by GC-MS/MS and the L. angustifolia, L. latifolia and George 90 hydroalcoholic extracts were analyzed by HPLC-DAD. The antioxidant, antibacterial, antifungal and antiproliferative assays revealed that all the investigated species showed significant activities. The results highlighted the chemical composition and the promising biological potentials of the L. angustifolia, L. latifolia and George 90 lavender species, validating their ethnomedicinal value, which offers potential applications as natural drugs.

14.
Pharmaceuticals (Basel) ; 16(1)2023 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-36678629

RESUMO

Inflammation is the supreme biological response to illness. In the Hauts-Bassins region, in traditional medicine, all parts of Cassia sieberiana and Piliostigma thonningii are used to treat hepatitis and inflammation. The aim of this study was to evaluate the in vitro antioxidant and anti-inflammatory activities of their aqueous extracts. High performance liquid chromatography with photodiode array (HPLC-DAD) and ultra-high-performance liquid chromatography coupled with high-resolution mass spectrometry (UHPLC-MS/MS) analyses highlighted the presence of polyphenols and flavonoids. Antioxidant and anti-inflammatory activities were measured by various methods such as DPPH (2,2-diphenyl-1-picrylhydrazyl), ABTS 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid), TAC (total antioxidant capacity), anti-protease, anti-lipoxygenase, and membrane stabilization. The best antioxidant activity was observed in the bark (DPPH: IC50 = 13.45 ± 0.10 µg/mL) and roots (TAC = 29.68 ± 1.48 mg AAE/g DW) of Piliostigma thonningii and in the roots (ABTS: IC50 = 1.83 ± 0.34 µg/mL) of Cassia sieberiana. The best anti-inflammatory activity was observed in the bark (anti-lipoxygenase: IC50 = 13.04 ± 1.99 µg/mL) and leaves (anti-proteases: IC50 = 75.74 ± 1.07 µg/mL, membrane stabilization: IC50 = 48.32 ± 6.39 µg/mL) of Cassia sieberiana. Total polyphenols (ABTS: r = -0.679, TAC: r = 0.960) and condensed tannins (ABTS: r = -0.702, TAC: r = 0.701) were strongly correlated with antioxidant activity. Total flavonoids (anti-proteases: r = -0.729), condensed tannins (anti-proteases: r = 0.698), and vitamin C (anti-proteases: r = -0.953) were strongly correlated with anti-inflammatory activity. Total polyphenols, flavonoids, condensed tannins, and vitamin C could contribute to the antioxidant and anti-inflammatory activities of the two studied plants. These results could validate the traditional use of these plants to treat various inflammatory diseases.

15.
Nanomaterials (Basel) ; 12(19)2022 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-36234595

RESUMO

Catalytic ozonation is an important water treatment method among advanced oxidation processes (AOPs). Since the first development, catalytic ozonation has been consistently improved in terms of catalysts used and the optimization of operational parameters. The aim of this work is to compare the catalytic activity of polyaniline (PANI) and thermally treated polyaniline (PANI 900) in the catalytic ozonation of ibuprofen solutions at different pH values (4, 7, and 10). Catalysts were thoroughly characterized through multiple techniques (SEM, Raman spectroscopy, XPS, pHPZC, and so on), while the oxidation process of ibuprofen solutions (100 mgL-1) was assessed by several analytical methods (HPLC, UV254, TOC, COD, and BOD5). The experimental data demonstrate a significant improvement in ibuprofen removal in the presence of prepared solids (20 min for PANI 900 at pH10) compared with non-catalytic processes (56 min at pH 10). Moreover, the influence of solution pH was emphasized, showing that, in the basic region, the removal rate of organic substrate is higher than in acidic or neutral range. Ozone consumption mgO3/mg ibuprofen was considerably reduced for catalytic processes (17.55-PANI, 11.18-PANI 900) compared with the absence of catalysts (29.64). Hence, beside the ibuprofen degradation, the catalysts used are very active in the mineralization of organic substrate and/or formation of biodegradable compounds. The best removal rate of target pollutants and oxidation by-products was achieved by PANI 900, although raw polyaniline also presents important activity in the oxidation process. Therefore, it can be stated that polyaniline-based catalysts are effective in the oxidation processes.

16.
Materials (Basel) ; 15(20)2022 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-36295404

RESUMO

With their phytoconstituents acting as reducing and capping agents, natural extracts can be considered a viable alternative for the obtaining of metallic nanoparticles. The properties of phytosynthesized nanoparticles are dependent upon size and morphology, which, in turn, can be tailored by adjusting different parameters of the phytosynthesis process (such as the extracts' composition). In the present study, we aimed to evaluate, for the first time in the literature, the influence of the extraction method and extract concentration on the morphological and biological properties (antioxidant and antibacterial activity) of silver nanoparticles phytosynthesized using Echinacea pupurea L. extracts. The obtained results revealed that the use of the low-concentration Echinacea hydro-alcoholic extract obtained via classical temperature extraction led to the development of nanoparticles with the smallest dimensions (less than 10 nm), compared with the use of extracts obtained with higher concentrations and the extract obtained via the microwave method. The developed nanomaterials exhibited enhanced antioxidant effects (determined via the DPPH assay) and antimicrobial properties (against Escherichia coli and Candida albicans), compared with the parent extracts.

17.
Nanomaterials (Basel) ; 12(4)2022 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-35214942

RESUMO

Analgesics and nonsteroidal anti-inflammatory drugs (NSAIDs) such as paracetamol, diclofenac, and ibuprofen are frequently encountered in surface and ground water, thereby posing a significant risk to aquatic ecosystems. Our study reports the catalytic performances of nanosystems TiO2-MexOy (Me = Ce, Sn) prepared by the sol-gel method and deposited onto glass slides by a dip-coating approach in the removal of paracetamol from aqueous solutions by catalytic ozonation. The effect of catalyst type and operation parameters on oxidation efficiency was assessed. In addition to improving this process, the present work simplifies it by avoiding the difficult step of catalyst separation. It was found that the thin films were capable of removing all pollutants from target compounds to the oxidation products.

18.
Materials (Basel) ; 14(22)2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34832297

RESUMO

Wastewater treatment remains a critical issue globally, despite various technological advancements and breakthroughs. The study of different materials and technologies gained new valences in the last years, in order to obtain cheap and efficient processes, to obtain a cleaner environment for future generations. In this context, the present review paper presents the new achievements in the materials domain with highlights on apatitic materials used for decontamination of water loaded with heavy metals. The main goal of this review is to present the adsorptive removal of heavy metals using hydroxyapatite-based adsorbents, offering a general overview regarding the recent progress in this particular area. Developing the current review, an attempt has been made to give appropriate recognition to the most recent data regarding the synthesis methods and targeted pollutants, including important information regarding the synthesis methods and precursors, morphological characteristics of the adsorbent materials and effectiveness of processes.

19.
Materials (Basel) ; 14(8)2021 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-33917755

RESUMO

The aim of the current paper is the development of phytosynthesized silver nanoparticles mediated by Raphanus sativus L. extracts obtained through two extraction methods (temperature and microwave) and to test their potential application for controlling apple crops pathogens. The phytosynthesized materials were characterized by X-ray diffraction, scanning electron microscopy, and transmission electron microscopy. All the materials were evaluated in terms of antioxidant and in vitro antimicrobial activity (against bacteria, molds, and yeast: Escherichia coli ATCC 8738, Staphylococcus aureus ATTC 25923, Pseudomonas aeruginosa ATCC 9027, Salmonella typhimurium ATCC 14028, Candida albicans ATCC 10231, Venturia inaequalis, Podosphaera leucotricha, Fusarium oxysporum ATCC 48112, Penicillium hirsutum ATCC 52323, and Aspergillus niger ATCC 15475). Considering the results obtained in the in vitro assays, formulations based on nanoparticles phytosynthesized using Raphanus sativus L. waste extracts (RS1N) were evaluated as potential antifungal agents for horticultural crops protection, against Venturia inaequalis and Podosphaera leucotricha through in vivo assays. For the DPPH assay, the inhibition (%) varied between 37.06% (for RS1N at 0.8 mg/mL concentration) and 83.72% (for RS1N at 7.2 mg/mL concentration) compared to 19.97% (for RS2N at 0.8 mg/mL) and only 28.91% (for RS2N at 7.2 mg/mL). Similar results were obtained for RS3N (85.42% inhibition at 7.2 mg/mL) compared with RS4N (21.76% inhibition at 7.2 mg/mL). Regarding the ABTS assay, the highest scavenger activity values were recorded for samples RS1N (91.43% at 1.6 mg/mL) and RS3N (96.62% at 1.6 mg/mL).

20.
Microbiologyopen ; 10(2): e1182, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33970538

RESUMO

Polyhydroxyalkanoates (PHAs) are biodegradable bioplastics that can be manufactured sustainably and represent a promising green alternative to petrochemical-based plastics. Here, we describe the complete genome of a new marine PHA-producing bacterium-Photobacterium ganghwense (strain C2.2), which we have isolated from the Black Sea seashore. This new isolate is psychrotolerant and accumulates PHA when glycerol is provided as the main carbon source. Transmission electron microscopy, specific staining with Nile Red visualized via epifluorescence microscopy and gas chromatography analysis confirmed the accumulation of PHA. This is the only PHA-producing Photobacterium for which we now have a complete genome sequence, allowing us to investigate the pathways for PHA production and other secondary metabolite synthesis pathways. The de novo assembly genome, obtained using open-source tools, comprises two chromosomes (3.5, 2 Mbp) and a megaplasmid (202 kbp). We identify the entire PHA synthesis gene cluster that encodes a class I PHA synthase, a phasin, a 3-ketothiolase, and an acetoacetyl-CoA reductase. No conventional PHA depolymerase was identified in strain C2.2, but a putative lipase with extracellular amorphous PHA depolymerase activity was annotated, suggesting that C2.2 is unable to degrade intracellular PHA. A complete pathway for the conversion of glycerol to acetyl-CoA was annotated, in accordance with its ability to convert glycerol to PHA. Several secondary metabolite biosynthetic gene clusters and a low number of genes involved in antibiotic resistance and virulence were also identified, indicating the strain's suitability for biotechnological applications.


Assuntos
Vias Biossintéticas/genética , Genoma Bacteriano , Photobacterium/genética , Photobacterium/metabolismo , Poli-Hidroxialcanoatos/biossíntese , Poli-Hidroxialcanoatos/genética , Acetilcoenzima A/metabolismo , Acetil-CoA C-Aciltransferase/genética , Aciltransferases/genética , Oxirredutases do Álcool/genética , Organismos Aquáticos/genética , Farmacorresistência Bacteriana/genética , Glicerol/metabolismo , Photobacterium/classificação , Lectinas de Plantas/genética , Plasmídeos , Microbiologia do Solo , Virulência/genética , Sequenciamento Completo do Genoma
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