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1.
Foods ; 13(13)2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38998507

RESUMO

Modifying starch allows for improvements in its properties to enable improved uses in food matrices, bioplastics, and encapsulating agents. In this research, four varieties of native potato starch were modified by acid treatment, enzymatic treatment, and ethanol precipitation, and their physicochemical, structural, thermal, and techno-functional characteristics were analyzed. According to FT-IR analysis, no influence of the modified starches on the chemical groups was observed, and by scanning electron microscopy (SEM), spherical and oval shapes were observed in the acid and enzymatic treatments, with particle sizes between 27 and 36 µm. In particular, the ethanolic precipitation treatment yielded a different morphology with a particle size between 10.9 and 476.3 nm, resulting in a significant decrease in gelatinization temperature (DSC) and more pronounced crystallites (XRD). On the other hand, the enzymatic treatment showed higher values for z-potential (ζ), and the acid treatment showed lower mass loss (TGA). Acid and ethanolic treatments affected the dough properties compared to native starches. The techno-functional properties showed a decrease in the water absorption index, an increase in the water solubility index, and varied swelling power behaviors. In conclusion, the modification of potato starches through acid, enzymatic, and ethanolic precipitation treatments alters their physicochemical properties, such as swelling capacity, viscosity, and thermal stability. This in turn affects their molecular structure, modifying morphology and the ability to form gels, which expands their applications in the food industry to improve textures, stabilize emulsions, and thicken products. Furthermore, these modifications also open new opportunities for the development of bioplastics by improving the biodegradability and mechanical properties of starch-based plastic materials.

2.
Artigo em Inglês | MEDLINE | ID: mdl-38980479

RESUMO

This study investigates the synthesize of activated carbon for carbon dioxide adsorption using palm kernel shell (PKS), a by-product of oil palm industry. The adsorbent synthesis involved a simple two-step carbonization method. Firstly, PKS was activated with potassium oxide (KOH), followed by functionalization with magnesium oxide (MgO). Surface analysis revealed that KOH activated PKS has resulted in a high specific surface area of 1086 m2/g compared to untreated PKS (435 m2/g). However, impregnation of MgO resulted in the reduction of surface area due to blockage of pores by MgO. Thermogravimetric analysis (TGA) demonstrated that PKS-based adsorbents exhibited minimal weight loss of less than 30% up to 500 °C, indicating their suitability for high-temperature applications. CO2 adsorption experiments revealed that PKS-AC-MgO has achieved a higher adsorption capacity of 155.35 mg/g compared to PKS-AC (149.63 mg/g) at 25 °C and 5 bars. The adsorption behaviour of PKS-AC-MgO was well fitted by both the Sips and Langmuir isotherms, suggesting a combination of both heterogeneous and homogeneous adsorption and indicating a chemical reaction between MgO and CO2. Thermodynamic analysis indicated a spontaneous and thermodynamically favourable process for CO2 capture by PKS-AC-MgO, with negative change in enthalpy (- 0.21 kJ/mol), positive change in entropy (2.44 kJ/mol), and negative change in Gibbs free energy (- 729.61 J/mol, - 790.79 J/mol, and - 851.98 J/mol) across tested temperature. Economic assessment revealed that the cost of PKS-AC-MgO is 21% lower than the current market price of commercial activated carbon, indicating its potential for industrial application. Environmental assessment shows a significant reduction in greenhouse gas emissions (381.9 tCO2) through the utilization of PKS-AC-MgO, underscoring its environmental benefits. In summary, the use of activated carbon produced from PKS and functionalised with MgO shows great potential for absorbing CO2. This aligns with the ideas of a circular economy and sustainable development.

3.
Artigo em Inglês | MEDLINE | ID: mdl-38976488

RESUMO

Purpose: Fingolimod (FTY720; FT), a structural analog of sphingosine, has potential ocular applications. The goal of this study was to develop an FT-loaded nanoemulsion (NE; FT-NE) formulation for the efficient and prolonged delivery of FT to the posterior segment of the eye through the topical route. Methods: FT-NE formulations were prepared using homogenization followed by the probe sonication method. The lead FT-NE formulations (0.15% and 0.3% w/v loading), comprising soybean oil as oil and Tween® 80 and Poloxamer 188 as surfactants, were further evaluated for in vitro release, surface morphology, filtration sterilization, and stability at refrigerated temperature. Ocular bioavailability following topical application of FT-NE (0.3%) was examined in Sprague-Dawley rats. Results: The formulation, at both dose levels, showed desirable physicochemical characteristics, a nearly spherical shape with homogenous nanometric size distribution, and was stable for 180 days (last time point checked) at refrigerated temperature postfiltration through a polyethersulfone (0.22 µm) membrane. In vitro release studies showed prolonged release over 24 h, compared with the control FT solution (FT-S). In vivo studies revealed that effective concentrations of FT were achieved in the vitreous humor and retina following topical application of FT-NE. Conclusions: The results from these studies demonstrate that the FT-NE formulation can serve as a viable platform for the ocular delivery of FT through the topical route.

4.
Materials (Basel) ; 17(12)2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38930324

RESUMO

The aim of this study was to evaluate the mobility of copper (Cu) and zinc (Zn) and their impact on the properties of bentonites and unfrozen water content. Limited research in this area necessitates further analysis to prevent the negative effects of metal interactions on bentonite effectiveness. Tests involved American (SWy-3, Stx-1b) and Slovak (BSvk) bentonite samples with Zn or Cu ion exchange. Sequential extraction was performed using the Community Bureau of Reference (BCR) method. Elemental content was analyzed via inductively coupled plasma optical emission spectrometry (ICP-OES). Unfrozen water content was measured using nuclear magnetic resonance (1H-NMR) and differential scanning calorimetry (DSC). Results showed a significant influence of the main cation (Zn or Cu) on ion mobility, with toxic metal concentrations increasing mobility and decreasing residual fractions. Mobile Zn fractions increased with larger particle diameters, lower clay content, and shorter interplanar spacing, while the opposite was observed for Cu. Zn likely accumulated in larger clay pores, while Cu was immobilized in the bentonite complex. The stability of Zn or Cu ions increased with higher clay content or specific surface area. Residual Zn or Cu fractions were highest in uncontaminated bentonites with higher unfrozen water content, suggesting the potential formation of concentrated solutions in sub-zero temperatures, posing a threat to the clay-water environment, especially in cold regions.

5.
Int J Biol Macromol ; 274(Pt 2): 133462, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38942403

RESUMO

In India, fish roes are generally considered worthless garbage and disposed of without recovering the valuable molecules, creating environmental and disposal problems. The present investigation aimed to optimize the extraction conditions, partial purification, and characterization of sialoglycoproteins (RRSGP) from Labeo rohita (rohu) roes. RSM generated optimum conditions for maximum RRSGP (70.49 %) extraction, which were 1.25 M NaCl, 1:32.5(w/v) solid-to-liquid ratio, 47.5 °C temperature, and 3 h time. Further, sialoglycoproteins from RRSGPs were partially purified, and result revealed that obtained peak-1 (PRRSGP) using QFF anion exchange chromatography exhibited higher glycoprotein and sialic acid content (p < 0.05). SDS-PAGE pattern of PRRSGP presented dominant bands of 97 kDa and 27 kDa glycoproteins. FTIR spectrum of PRRSGP confirmed the presence of glycated proteins. HPLC analysis revealed that PRRSGP consists of Neu5Ac. Furthermore, ß-elimination reaction elucidated that PRRSGP contained N-glycosidic linkage. PRRSGP exhibited tyrosine and glutamate as primary amino acids. Glycan part of PRRSGP presented mannose and N-acetyl galactosamine as dominant neutral and amino sugar, respectively. Furthermore, PRRSGP exhibited antioxidant activity with EC50 value for DPPH (8.79 mg/ml) and ABTS (2.21 mg/ml). Besides, RRSGP displayed better protein solubility, foaming, and emulsion properties. Therefore, rohu roes are potential source of sialoglycoproteins that can be recovered and used as bio-functional ingredients in food and nutraceutical applications.

6.
Bioresour Bioprocess ; 11(1): 58, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38849710

RESUMO

The global scientific community is deeply concerned about the deterioration of water quality resulting from the release of industrial effluents. This issue is of utmost importance as it serves to safeguard the environment and combat water pollution. The objective of this work is to elaborate a biomaterial of vegetable origin, based on the twigs of Aleppo pine, and to use it as an abundant and less expensive material for the treatment of wastewater. For this reason, the twigs were treated physically to get the powder called biomaterial FPA (Aleppo pine fiber), which was characterized by physicochemical, and spectroscopic analyses namely scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD). The crystallinity index of FPA was evaluated by the peak height method. The findings indicate that the FPA powder has an acidic nature, exhibiting a porous structure that promotes the adsorption and binding of molecules. Additionally, it has a zero charge point of 5.8 and a specific surface area of 384 m2.g-1. It is primarily composed of hydroxyl, carboxyl, and amine functional groups, along with mineral compounds and organic compounds, including cellulose and other mineral elements such as Ca, Mg, Fe, Na, P, Al, K, Ni, and Mo. Combining these characteristics, FPA biomaterial has considerable potential for use as an effective adsorbent biomaterial for various wastewater pollutants. Its abundance and relatively low cost make it an attractive solution to the growing challenges of water pollution worldwide.

7.
Int J Biol Macromol ; 269(Pt 1): 131973, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38692536

RESUMO

Medium-chain-length poly-3-hydroxyalkanoates (mcl-PHAs) with varied monomeric compositions were biosynthesized by producer bacteria fed with different fatty acids as carbon source. Octanoic-, lauric-, stearic-, and oleic acids were used to produce four types of mcl-PHAs viz. PHA-OC, PHA-LA, PHA-ST, and PHA-OL, respectively. The mcl-PHAs as film-casted preparations exhibit distinct traits e.g., PHA-OC and PHA-ST films are less flexible than PHA-LA while PHA-OL is a sticky, glue-like material; PHA-ST is opaque whereas PHA-OC, PHA-LA, and PHA-OL displayed transparent layers. The observation is attributed to polymer chain packing and side chain crystallization. A structure-property investigation of these biopolymers was carried out employing different spectroscopic and microscopic analyses in addition to thermal analyses. Comparative analyses of the results were applied in the interpretation and discussion of structure-property relationship.


Assuntos
Poli-Hidroxialcanoatos , Poli-Hidroxialcanoatos/química , Poli-Hidroxialcanoatos/biossíntese , Ácidos Graxos/química
8.
Int J Biol Macromol ; 271(Pt 2): 132603, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38788877

RESUMO

Surface-functionalized cellulose materials are developed for various purposes, including food additives and food contact materials. A new biologically relevant testing strategy has been developed based on guidance from the European Food Safety Authority to demonstrate the safety of several next-generation surface-functionalized cellulose materials. This strategy involves a complex three-stage simulated digestion to compare the health effects of thirteen novel different types of cellulose. The physical and chemical properties of surface-functionalized fibrillated celluloses differed depending on the type, amount, and location of functional groups such as sulfonate, TEMPO-oxidized carboxy, and periodate-chlorite oxidized dicarboxylic acid celluloses. Despite exposure to gastrointestinal fluids, the celluloses maintained their physicochemical properties, such as negative surface charges and high length-to-width/thickness aspect ratios. An established intestinal co-culture model was used to measure cytotoxicity, barrier integrity, oxidative stress, and pro-inflammatory response to create a toxicological profile for these unique materials. We conclude that the C6 carboxylated cellulose nanofibrils by TEMPO-oxidation induced the most toxicity in the biological model used in this study and that the observed effects were most prominent at the 4-hour post-exposure time point.


Assuntos
Celulose , Digestão , Celulose/química , Humanos , Propriedades de Superfície , Trato Gastrointestinal/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Modelos Biológicos , Células CACO-2 , Nanofibras/química
9.
Environ Sci Technol ; 58(20): 8919-8931, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38709668

RESUMO

For the first time, we present a much-needed technology for the in situ and real-time detection of nanoplastics in aquatic systems. We show an artificial intelligence-assisted nanodigital in-line holographic microscopy (AI-assisted nano-DIHM) that automatically classifies nano- and microplastics simultaneously from nonplastic particles within milliseconds in stationary and dynamic natural waters, without sample preparation. AI-assisted nano-DIHM identifies 2 and 1% of waterborne particles as nano/microplastics in Lake Ontario and the Saint Lawrence River, respectively. Nano-DIHM provides physicochemical properties of single particles or clusters of nano/microplastics, including size, shape, optical phase, perimeter, surface area, roughness, and edge gradient. It distinguishes nano/microplastics from mixtures of organics, inorganics, biological particles, and coated heterogeneous clusters. This technology allows 4D tracking and 3D structural and spatial study of waterborne nano/microplastics. Independent transmission electron microscopy, mass spectrometry, and nanoparticle tracking analysis validates nano-DIHM data. Complementary modeling demonstrates nano- and microplastics have significantly distinct distribution patterns in water, which affect their transport and fate, rendering nano-DIHM a powerful tool for accurate nano/microplastic life-cycle analysis and hotspot remediation.


Assuntos
Inteligência Artificial , Microplásticos , Poluentes Químicos da Água/química , Poluentes Químicos da Água/análise , Monitoramento Ambiental/métodos , Água/química
10.
Food Sci Biotechnol ; 33(8): 1751-1758, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38752125

RESUMO

Auricularia auricular (A. auricula), a nutritious fungus and traditional medicinal resource, is known for melanin. This review aims to summarize the research progress on melanin in A. auricula, specifically focusing on biosynthesis, fermentation production, extraction processes, physicochemical characterization, biological functions, and applications. The biosynthesis of melanin in A. auricula primarily involves the oxidative polymerization reaction of phenolic compounds. To enhance melanin production, strategies such as deep fermentation culture, selection of optimal fermentation materials, and optimization of the culture medium have been employed. Various extraction processes have been compared to determine their impact on the physicochemical properties and stability of melanin. Moreover, the antioxidant and antibiofilm activities of A. auricula melanin, as well as its potential beneficial effects on the human body through in vivo experiments, have been investigated. These findings provide valuable insights into the application of A. auricula melanin and serve as a reference for future research in this field.

11.
Pharm Res ; 41(5): 1007-1020, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38561579

RESUMO

PURPOSE: Products formulated for intramammary (IMM) infusion are intended for the delivery of therapeutic moieties directly into the udder through the teat canal to maximize drug exposure at the targeted clinical site, the mammary gland, with little to no systemic drug exposure. Currently, to our knowledge, there has been no in-vitro matrix system available to differentiate between IMM formulations. Our goal is to develop A custom tailored in-vitro "Matrix of Chemistry, Manufacturing and Control" (MoCMC) System to be a promising future tool for identifying inequivalent IMM formulations. MoCMC can detect inter and intra batch variabilities, thereby identifying potential generics versus brand product similarities or differences with a single numeric value and a specific & distinctive fingerprint. METHODS: The FDA-approved IMM formulation, SPECTRAMASTⓇ LC, was selected as the reference product for the MoCMC. Twelve in-house test formulations containing ceftiofur hydrochloride were formulated and characterized. The MoCMC was developed to include six input parameters and three output parameters. The MoCMC system was used to evaluate and compare SPECTRAMASTⓇ LC with its in-house formulations. RESULTS: Based on the MoCMC generated parameters, the distinctive fingerprints of MoCMC for each IMM formulations, and the statistical analyses of MCI and PPI values, in-house formulations, F-01 and F-02 showed consistency while the rest of in-house formulations (F-03-F-12) were significantly different as compared to SPECTRAMASTⓇ LC. CONCLUSION: This research showed that the MoCMC approach can be used as a tool for intra batch variabilities, generics versus brand products comparisons, post-approval formulations changes, manufacturing changes, and formulation variabilities.


Assuntos
Química Farmacêutica , Animais , Química Farmacêutica/métodos , Composição de Medicamentos/métodos , Feminino , Glândulas Mamárias Animais/metabolismo , Antibacterianos/análise , Antibacterianos/administração & dosagem , Medicamentos Genéricos
12.
Chempluschem ; 89(7): e202400122, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38578430

RESUMO

Collagen-based aerogels have great potential for topical biomedical applications. Collagen's natural affinity with skin, biodegradability, and gelling behavior are compelling properties to combine with the structural integrity of highly porous matrices in the dry form (aerogels). This work aimed to produce a novel collagen-based aerogel and to perform the material's solid-state and physicochemical characterization. Aerogels were obtained by performing different solvent exchange approaches of a collagen-gelled extract and drying the obtained alcogels with supercritical CO2. The resulting aerogels showed a sponge-like structure with a relatively dense mesoporous network with a specific surface area of 201-203 m2/g, a specific pore volume of 1.08-1.15 cm3/g, and a mean pore radius of ca. 14.7 nm. Physicochemical characterization confirmed that the obtained aerogels are composed of pure collagen, and the aerogel production process does not impact protein tertiary structure. Finally, the material swelling behavior was assessed at various pH values (4, 7, and 10). Collagen aerogels presented a high water uptake capacity up to ~2700 wt. %, pH-dependent stability, and swelling behavior in aqueous media. The results suggest that this collagen aerogel could be a promising scaffold candidate for topical biomedical applications.


Assuntos
Colágeno , Géis , Géis/química , Colágeno/química , Porosidade , Concentração de Íons de Hidrogênio , Animais , Administração Tópica
13.
Heliyon ; 10(7): e28125, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38560258

RESUMO

The aim of the present study is the valorization of the essential oil of Mentha suaveolens Ehrh. The research plan and methods included 3-axis: the first axis consists of studying the organoleptic and physicochemical characterization of the essential oil, the second is the chemical analysis carried out by Gas Chromatography/Mass Spectrometry (GC/MS) and the third consists of evaluating its antimicrobial activity against selected microorganisms. The results obtained for the organoleptic and physicochemical properties are as follows: appearance: Liquid, mobile and clear, odor: Strong odor characteristic of Mentha suaveolens Ehrh, color: Pale yellow; relative density (0.92), miscibility with ethanol (1V/2V), freezing point (Tfreezing < -10 °C), refractive index (1.5256), rotating power (+0.825), acid index (1.68), ester index (68.44), saponification index (70.13) and iodine index (12.05).Chemical analysis identified 69 compounds which are mostly oxygenated monoterpenes such as piperitenone oxide (32.55%), pulegone (10.14%), piperitone oxide (8.34%), etc. The microbiological tests were carried out by an agar diffusion test using the essential oil of Mentha suaveolens Ehrh. The microbiological tests were carried out by a diffusion test on agar, these tests are carried out on six microbial strains (five bacteria and one yeast).The inhibitory effect of our oil is well marked against bacteria: Proteus mirabilis (17.50 ± 0.70 mm at 50 µL/mL), Enterococcus faecalis (17.00 ± 1.00 mm at 50 µL/mL) and Staphylococcus coagulase negative (16.33 ± 0.57 mm at 50 µL/mL) while it was moderate against Escherichia coli (14.33 ± 1.15 mm at 50 µL/mL) and Streptococcus spp (13.00 ± 0.00 mm at 50 µL/mL) as well as against yeast, Candida albicans (15.33 ± 1.52 mm at 50 µL/mL). It appears from these results that our oil is of high quality and can be used in several areas. The results obtained are therefore promising and thus open the way for manufacturers to use this essential oil of Mentha suaveolens Ehrh in the pharmaceutical, cosmetic, agricultural and food industries.

14.
Molecules ; 29(7)2024 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-38611922

RESUMO

Propolis extracts have been widely studied due to their popularity in traditional medicine, presenting incredible biodiversity. This study aimed to analyze propolis extracts' phytochemical, physicochemical, and biological activities from four different biogeographic zones of the Huila region (Colombia). The raw material samples were collected by the scraping method and the ethanolic extracts (EEPs) were obtained by cold maceration with ethanol (96%). The physicochemical and sensory characterization was carried out according to the protocols recommended by the Brazilian Ministry of Agriculture and the main components of the EEPs were identified by LC-HRMS analysis. The determination of total phenols and flavonoids was carried out using colorimetric techniques. The antioxidant activity, cytotoxicity, and cell cycle regulation analyses in L929 and HGnF cells were evaluated using DPPH, Alamar Blue, and 7-amino actinomycin D (7-AAD) assays. The propolis samples presented an average yield of 33.1%, humidity between 1.6 and 2.8%, melting point between 54 and 62 °C, ashes between 1.40 and 2.19%, and waxes of 6.6-17.9%, respectively. The sensory characteristics of all samples were heterogeneous, complying with the quality specifications established by international standards. The polyphenolic and total flavonoid content was representative in the samples from Quebradon (255.9 ± 9.2 mg GAE/g, 543.1 ± 8.4 mg QE/g) and Arcadia (543.1 ± 8.4 mg GAE/g, 32.5 ± 1.18 g QE/g) (p < 0.05) that correlated with high antioxidant activity (Quebradon: 37.2 ± 1.2 µmol/g, Arcadia: 38.19 ± 0.7 µmol/g). In the chemical composition analysis, 19 compounds were characterized as phenolic acids and flavonoids, the most representative being chrysoeriol-O-methyl-ether, ellagic acid, and 3,4-O-dimethylcaffeic acid. Regarding biological activity, Quebradon and Arcadia propolis presented low toxicity with IC50 of 2.83 ± 2.3 mg/mL and 4.28 ± 1.4 mg/mL in HGnF cells, respectively, and an arrest of the cell cycle in the G2/M phase of 71.6% and 50.8% compared to the control (11.9%) (p < 0.05). In general, the results of this study contribute to the identification of valid quality criteria to evaluate Colombian propolis, contributing to its study and chemical and biological characterization as a source of raw material for industrial and pharmaceutical use. In addition, Quebradon and Arcadia propolis can be important sources of bioactive molecules for the development of new drugs.


Assuntos
Ascomicetos , Própole , Antioxidantes/farmacologia , Colômbia , Própole/farmacologia , Ciclo Celular , Etanol , Flavonoides/farmacologia
15.
Molecules ; 29(8)2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38675630

RESUMO

AHP-3a, a triple-helix acidic polysaccharide isolated from Alpinia officinarum Hance, was evaluated for its anticancer and antioxidant activities. The physicochemical properties and structure of AHP-3a were investigated through gel permeation chromatography, scanning electron microscopy (SEM), Fourier transform infrared spectroscopy, and nuclear magnetic resonance (NMR) spectroscopy. The weight-average molecular weight of AHP-3a was 484 kDa, with the molar percentages of GalA, Gal, Ara, Xyl, Rha, Glc, GlcA, and Fuc being 35.4%, 21.4%, 16.9%, 11.8%, 8.9%, 3.1%, 2.0%, and 0.5%, respectively. Based on the results of the monosaccharide composition analysis, methylation analysis, and NMR spectroscopy, the main chain of AHP-3a was presumed to consist of (1→4)-α-D-GalpA and (1→2)-α-L-Rhap residues, which is a pectic polysaccharide with homogalacturonan (HG) and rhamnogalacturonan-I (RG-I) structural domains containing side chains. In addition, the results of the antioxidant activity assay revealed that the ability of AHP-3a to scavenge DPPH, ABTS, and OH free radicals increased with an increase in its concentration. Moreover, according to the results from the EdU, wound healing, and Transwell assays, AHP-3a can control the proliferation, migration, and invasion of HepG2 and Huh7 hepatocellular carcinoma cells without causing any damage to healthy cells. Thus, AHP-3a may be a natural antioxidant and anticancer component.


Assuntos
Alpinia , Antioxidantes , Compostos de Bifenilo , Polissacarídeos , Alpinia/química , Polissacarídeos/química , Polissacarídeos/farmacologia , Polissacarídeos/isolamento & purificação , Humanos , Antioxidantes/farmacologia , Antioxidantes/química , Proliferação de Células/efeitos dos fármacos , Antineoplásicos/farmacologia , Antineoplásicos/química , Células Hep G2 , Peso Molecular , Linhagem Celular Tumoral , Monossacarídeos/análise , Monossacarídeos/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Antineoplásicos Fitogênicos/química , Picratos/química , Picratos/antagonistas & inibidores , Espectroscopia de Infravermelho com Transformada de Fourier
16.
Methods Mol Biol ; 2789: 3-17, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38506986

RESUMO

Nanotechnology for drug delivery has made significant advancements over the last two decades. Innovations have been made in cancer research and development, including chemotherapies, imaging agents, and vaccine strategies, as well as other therapeutic areas, e.g., the recent commercialization of mRNA lipid nanoparticles as vaccines against the SARS-CoV-2 virus. The field has also seen technological advancements to aid in addressing the complex questions posed by these novel therapies. In this latest edition of protocols and methods for nanoparticle characterization, we highlight both old and new methodologies for defining physicochemical properties, present both in vitro and in vivo methods to test for a variety of immunotoxicities, and describe assays used for pharmacological studies to assess drug release and tissue distribution.


Assuntos
Nanopartículas , Vacinas , Nanomedicina/métodos , Nanotecnologia/métodos , Sistemas de Liberação de Medicamentos/métodos , Nanopartículas/química
17.
Int J Biol Macromol ; 264(Pt 1): 130553, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38431005

RESUMO

Functional calcium-phosphate-chitosan adsorbents for fluoride (F-) removal from water with different proportions of calcium (0.7 or 1.4 % w/v) were synthesized by: i) ionotropic gelation technique followed by drying in a convection oven (IGA) or freeze drying (FDA); ii) freeze-gelation followed by drying in a convection oven (FGA). Adsorbents were analyzed by SEM-EDX and FTIR- ATR. F- removal percentages higher than 45 % were obtained with calcium-phosphate-chitosan adsorbents for an initial F- concentration of 9.6 mg L-1. Optimal conditions for F- removal were attained, using calcium-phosphate- chitosan adsorbents synthesized by ionotropic gelation with 0.7 % of Ca (IGA0.7). Under these conditions, initial F- concentration of 5 mg L-1, was reduced below the maximum limit of 1.5 mg L-1 established by WHO. Regeneration of IGA0.7 was achieved in acid media. The performance of IGA0.7 was slightly reduced in the presence of coexisting anions (nitrate, carbonate, arsenate). Adsorption kinetics was represented satisfactorily by the pseudo-second order equation; Langmuir isotherm provided the best fit to the equilibrium data and IGA0.7 exhibited a maximum F- adsorption capacity qL = 132.25 mg g-1. IGA0.7 particles were characterized by thermogravimetry coupled to FTIR, XRD, XPS and SEM-EDX. The calcium-phosphate-chitosan adsorbents constitute a suitable and emerging material for water defluorination.


Assuntos
Quitosana , Poluentes Químicos da Água , Purificação da Água , Fluoretos , Cálcio , Água , Fosfatos de Cálcio , Adsorção , Cinética , Concentração de Íons de Hidrogênio
18.
Microb Cell Fact ; 23(1): 59, 2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38388436

RESUMO

BACKGROUND: Polyhydroxybutyrate is a biopolymer produced by bacteria and archaea under nitrogen-limiting conditions. PHB is an essential polymer in the bioplastic sector because of its biodegradability, eco-friendliness, and adaptability. The characterization of PHB is a multifaceted process for studying the structure and its properties. This entire aspect can assure the long-term viability and performance attributes of the PHB. The characteristics of PHB extracted from the halophile Brachybacterium paraconglomeratum were investigated with the objective of making films for application in healthcare. RESULTS: This was the first characterization study on PHB produced by a rare halophile, Brachybacterium paraconglomeratum (MTCC 13074). In this study, the strain produced 2.72 g/l of PHB for.5.1 g/l of biomass under optimal conditions. Methods are described for the determination of the physicochemical properties of PHB. The prominent functional groups CH3 and C = O were observed by FT-IR and the actual chemical structure of the PHB was deduced by NMR. GCMS detects the confirmation of four methyl ester derivatives of the extracted PHB in the sample. Mass spectrometry revealed the molecular weight of methyl 3-hydroxybutyric acid (3HB) present in the extract. The air-dried PHB films were exposed to TGA, DSC and a universal testing machine to determine the thermal profile and mechanical stability. Additionally, the essential property of biopolymers like viscosity was also assessed for the extracted PHB. CONCLUSIONS: The current study demonstrated the consistency and quality of B. paraconglomeratum PHB. Therefore, Brachybacterium sps are also a considerable source of PHB with desired characteristics for industrial production.


Assuntos
Actinobacteria , Actinomycetales , Poli-Hidroxibutiratos , Espectroscopia de Infravermelho com Transformada de Fourier , Polímeros , Biopolímeros , Hidroxibutiratos/química
19.
Int J Biol Macromol ; 264(Pt 1): 130459, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38423432

RESUMO

This work investigated and compared the physicochemical characteristics, and antioxidant and antihyperglycemic properties in vitro of polysaccharides from a single banana flower variety (BFPs) extracted by different methods. BFPs extracted using hot water (HWE), acidic (CAE), alkaline (AAE), enzymatic (EAE), ultrasonic (UAE) and hot water-alkaline (HAE) methods showed different chemical composition, monosaccharide composition, molecular weight, chain conformation and surface morphology, but similar infrared spectra characteristic, main glycosidic residues, crystalline internal and thermal stability, suggesting that six methods have diverse impacts on the degradation of BFPs without changing the main structure. Then, among six BFPs, the stronger antioxidant activity in vitro was found in BFP extracted by HAE, which was attributed to its maximum uronic acid content (21.67 %) and phenolic content (0.73 %), and moderate molecular weight (158.48 kDa). The highest arabinose and guluronic acid contents (18.59 % and 1.31 % in molar ratios, respectively) and the lowest uronic acid content (14.30 %) in BFP extracted by HWE contributed to its better α-glucosidase inhibitory activity in vitro (66.55 %). The data offered theoretical evidence for choosing suitable extraction methods to acquire BFPs with targeted biological activities for applications, in which HAE and HWE could serve as beneficial methods for preparing antioxidant BFP and antihyperglycemic BFP, respectively.


Assuntos
Antioxidantes , Musa , Antioxidantes/farmacologia , Antioxidantes/química , Hipoglicemiantes/farmacologia , Hipoglicemiantes/química , Polissacarídeos/farmacologia , Polissacarídeos/química , Flores , Água/química , Ácidos Urônicos
20.
Nanomaterials (Basel) ; 14(4)2024 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-38392745

RESUMO

Because of the physiological and cardiac changes associated with cardiovascular disease, tissue engineering can potentially restore the biological functions of cardiac tissue through the fabrication of scaffolds. In the present study, hybrid nanofiber scaffolds of poly (vinyl alcohol) (PVA) and bioglass type 58S (58SiO2-33CaO-9P2O5, Bg) were fabricated, and their effect on the spontaneous activity of chick embryonic cardiomyocytes in vitro was determined. PVA/Bg nanofibers were produced by electrospinning and stabilized by chemical crosslinking with glutaraldehyde. The electrospun scaffolds were analyzed to determine their chemical structure, morphology, and thermal transitions. The crosslinked scaffolds were more stable to degradation in water. A Bg concentration of 25% in the hybrid scaffolds improved thermal stability and decreased degradation in water after PVA crosslinking. Cardiomyocytes showed increased adhesion and contractility in cells seeded on hybrid scaffolds with higher Bg concentrations. In addition, the effect of Ca2+ ions released from the bioglass on the contraction patterns of cultured cardiomyocytes was investigated. The results suggest that the scaffolds with 25% Bg led to a uniform beating frequency that resulted in synchronous contraction patterns.

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