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1.
Int J Nanomedicine ; 19: 3891-3905, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38711613

RESUMO

Introduction: The synthesis of nanoparticles using naturally occurring reagents such as vitamins, sugars, plant extracts, biodegradable polymers and microorganisms as reductants and capping agents could be considered attractive for nanotechnology. These syntheses have led to the fabrication of limited number of inorganic nanoparticles. Among the reagents mentioned above, plant-based materials seem to be the best candidates, and they are suitable for large-scale biosynthesis of nanoparticles. Methods: The aqueous extract of Moringa peregrina leaves was used to synthesize silver nanoparticles. The synthesized nanoparticles were characterized by various spectral studies including FT-IR, SEM, HR-TEM and XRD. In addition, the antioxidant activity of the silver nanoparticles was studied viz. DPPH, ABTS, hydroxyl radical scavenging, superoxide radical scavenging, nitric oxide scavenging potential and reducing power with varied concentrations. The anticancer potential of the nanoparticles was also studied against MCF-7 and Caco-2 cancer cell lines. Results: The results showed that silver nanoparticles displayed strong antioxidant activity compared with gallic acid. Furthermore, the anticancer potential of the nanoparticles against MCF-7 and Caco-2 in comparison with the standard Doxorubicin revealed that the silver nanoparticles produced significant toxic effects against the studied cancer cell lines with the IC50 values of 41.59 (Caco-2) and 26.93 (MCF-7) µg/mL. Conclusion: In conclusion, the biosynthesized nanoparticles using M. peregrina leaf aqueous extract as a reducing agent showed good antioxidant and anticancer potential on human cancer cells and can be used in biological applications.


Assuntos
Antioxidantes , Química Verde , Nanopartículas Metálicas , Moringa , Extratos Vegetais , Folhas de Planta , Prata , Humanos , Prata/química , Prata/farmacologia , Nanopartículas Metálicas/química , Células MCF-7 , Células CACO-2 , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Moringa/química , Antioxidantes/farmacologia , Antioxidantes/química , Folhas de Planta/química , Sobrevivência Celular/efeitos dos fármacos , Antineoplásicos/farmacologia , Antineoplásicos/química
2.
Inorg Chem ; 62(38): 15550-15564, 2023 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-37698585

RESUMO

A novel cobalt hydrogen-bonded organic framework (Co-HOF, C24H14CoN4O8) was synthesized from a mixed linker, that is, 2,5-pyridinedicarboxylic acid (PDC) and 2,2'-bipyridyl (BPY) linkers and cobalt ion through a simple, one-pot, low-cost, and scalable solvothermal method. The Co-HOF was fully characterized using several analytical and spectroscopic techniques including single-crystal X-ray diffraction, diffuse reflectance spectroscopy, Fourier transform infrared spectroscopy, scanning electron microscopy, energy-dispersive X-ray, and X-ray photoelectron spectroscopy. The Co-HOF exhibits high thermal and chemical stabilities compared to previously reported HOF materials. Moreover, Co-HOF shows excellent photocatalytic activity under visible light irradiation due to its narrow band gap of 2.05 eV. The cycloaddition reaction of CO2 to variable epoxides was investigated to evaluate the photocatalytic performance of Co-HOF under visible light radiation and was found to produce the corresponding cyclic carbonates in yields up to 99.9%.

3.
Dalton Trans ; 52(25): 8580-8600, 2023 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-37096427

RESUMO

The need for energy storage and conversion is growing as a result of the worsening consequences of climate change and the depletion of fossil fuels. Energy conversion and storage requirements are rising as a result of environmental problems including global warming and the depletion of fossil fuels. The key to resolving the energy crisis is anticipated to be the quick growth of sustainable energy sources including solar energy, wind energy, and hydrogen energy. In this review, we have focused on discussing various quantum dots (QDs) and polymers or nanocomposites used for SCs and have provided examples of each type's performance. Effective QD use has really led to increased performance efficiency in SCs. The use of quantum dots in energy storage devices, batteries, and various quantum dots synthesis have all been emphasized in a number of great literature articles. In this review, we have homed in on the electrode materials based on quantum dots and their composites for storage and quantum dot based flexible devices that have been published up to this point.

4.
Nanomaterials (Basel) ; 13(6)2023 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-36985942

RESUMO

Supercapacitors have become a popular form of energy-storage device in the current energy and environmental landscape, and their performance is heavily reliant on the electrode materials used. Carbon-based electrodes are highly desirable due to their low cost and their abundance in various forms, as well as their ability to easily alter conductivity and surface area. Many studies have been conducted to enhance the performance of carbon-based supercapacitors by utilizing various carbon compounds, including pure carbon nanotubes and multistage carbon nanostructures as electrodes. These studies have examined the characteristics and potential applications of numerous pure carbon nanostructures and scrutinized the use of a wide variety of carbon nanomaterials, such as AC, CNTs, GR, CNCs, and others, to improve capacitance. Ultimately, this study provides a roadmap for producing high-quality supercapacitors using carbon-based electrodes.

5.
J Dairy Sci ; 105(11): 8621-8637, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36207183

RESUMO

Lactobacillus reuteri fortified camel milk infant formula (CMIF) was produced. The effect of encapsulation in different matrices (sodium alginate and galacto-oligosaccharides) via spray drying, simulated infant gastrointestinal digestion (SIGID), and storage conditions (temperature and humidity) on the viability of L. reuteri in CMIF and the physicochemical properties of CMIF were evaluated. Compared with free cells, probiotic cell viability was significantly enhanced against SIGID conditions upon encapsulation. However, L. reuteri viability in CMIF decreased after 60 d of storage, predominantly at higher storage humidity and temperature levels. At the end of the storage period, significant changes in the color values were observed in all CMIF, with a reduction in their greenness, an increase in yellowness, and a wide variation in their whiteness. Moreover, pH values and caking behavior of all CMIF stored at higher temperature (40°C) and humidity [water activity (aw) = 0.52] levels were found to be significantly higher than the samples stored under other conditions. Over 30 d of storage at lower humidity conditions (aw = 0.11 and 0.33) and room temperature (25°C), no significant increase in CMIF lipid oxidation rates was noted. Fourier-transform infrared spectroscopy analysis showed that, compared with the other storage conditions, CMIF experienced fewer changes in functional groups when stored at aw = 0.11. Microscopic images showed typical morphological characteristics of milk powder, with round to spherical-shaped particles. Overall, camel milk fortified with encapsulated L. reuteri can be suggested as a promising alternative in infant formula industries, potentially able to maintain its physicochemical characteristics as well as viability of probiotic cells when stored at low humidity levels (aw = 0.11) and temperature (25°C), over 60 d of storage.


Assuntos
Limosilactobacillus reuteri , Probióticos , Animais , Leite/química , Camelus , Fórmulas Infantis/análise , Pós/química , Sobrevivência Celular , Probióticos/análise , Alginatos/análise , Água/análise , Digestão , Lipídeos/análise
6.
Sci Rep ; 12(1): 6614, 2022 04 22.
Artigo em Inglês | MEDLINE | ID: mdl-35459886

RESUMO

Date palm fruits (Phoenix dactylifera L.) were found to contain high levels of allomelanin (1.2-5.1%). The melanin is localized in the tanniferous cells between the inner and outer mesocarp tissues of the fruit. The melanin, extracted with 2 M sodium hydroxide, consisted of amorphous graphene-like granular structures of irregular shape and variable size. The date fruit melanin mainly comprises carbon (64.6%) and oxygen (30.6) but no nitrogen, and was thermally stable. It has radical scavenging (63.6-75.1 IC50, µg/mL), antimicrobial (250-1000 µg/mL), hypoglycemic (51.8-58.2%), and angiotensin-converting-enzyme inhibitory (65.8%) effects. The high level of melanin in date fruits highlights the importance of investigating its dietary intake and its impact on nutrition. This study also suggests that date fruit melanin can be a functional ingredient in foods, food packages, pharmaceuticals, and cosmetics.


Assuntos
Phoeniceae , Frutas/química , Melaninas/análise , Fenóis/análise , Phoeniceae/química , Extratos Vegetais/farmacologia
7.
Front Nutr ; 8: 642846, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34222297

RESUMO

The effects of high-pressure processing (HPP) compared to thermal treatments on the quality of camel vs. bovine cheeses were studied. The study showed that camel milk has a lower microbial load compared to bovine milk, which is maintained during 7 days' storage of the processed milk. The effect of three HPP treatments (350, 450, and 550 MPa for 5 min at 4°C) and two pasteurization treatments (65°C for 30 min and 75°C for 30 s) on the quality of soft unripened camel and bovine milk cheeses were accessed. The cheeses were evaluated for pH, yield, proximate composition, textural and rheological properties, microstructure, and protein profile by SDS-PAGE electrophoresis. The effects of the treatments on cheese's hardness were different between the camel and bovine cheeses; while heat treatment at 65°C for 30 min gave the hardest bovine milk cheese (1,253 ± 20), HPP treatment at 350 MPa for 5 min gave the highest value for camel milk cheese (519 ± 5) (p < 0.05). The hardness of the cheeses was associated with low yield and moisture content. SDS-PAGE electrophoresis revealed that extensive proteolysis might have contributed to the softness of camel cheeses compared to bovine and suggested the involvement of some residual enzyme activities.

8.
J Dairy Sci ; 104(5): 5279-5284, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33663820

RESUMO

Camel milk (CM) is gaining scientific attention due to its potential health and therapeutic benefits. Fermented drinkable yogurts (labans) were prepared from CM and bovine milk (BM) using mixed Streptococcus thermophilus and Lactobacillus delbrueckii ssp. bulgaricus bacteria supplemented with 1 of 2 hydrocolloids: pectin (0.1-0.3%) or sodium alginate (0.1-0.5%). The different labans were compared by studying their acidity and rheology as well as their structural and sensory properties. The CM and BM labans had titratable acidity values that ranged from 0.85 to 1.27 and 0.61 to 0.93%, respectively. Pectin at 0.2% enhanced the rheological properties of BM labans, but had no effect in CM labans. Sodium alginate at 0.3% and 0.5% increased viscosity, elastic or storage modulus (G'), and viscous or loss modulus (G″) values for both types of laban. Scanning electron microscopy indicated that the CM laban contained lower levels of "spike-like structures" than BM laban, and that the addition of hydrocolloids improved this effect. Quantitative descriptive sensory analysis showed that CM labans fortified with either 0.2% pectin or 0.3% sodium alginate were comparable to commercial BM laban in viscous mouthfeel. Fortified CM labans were more acidic and had stronger flavors than unfortified samples. Overall, this study demonstrated that the addition of sodium alginate or pectin at intermediate levels permits production of palatable CM labans of a satisfactory viscous consistency.


Assuntos
Camelus , Leite , Alginatos , Animais , Bovinos , Fermentação , Pectinas , Streptococcus thermophilus , Iogurte
9.
Front Plant Sci ; 11: 977, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32733510

RESUMO

Date fruits are special representative of hard fruits and one of the richest sources of dietary silica and edible lignin, which are believed to have several health benefits. In this study, we used optical and scanning electron microscopy (SEM) to investigate the presence of associations between silicification and lignification in date fruits (Phoenix dactylifera, L.). Phloroglucinol staining was employed to observe lignification in date fruits, while silicification was studied by SEM of whole fruits and their acid digesta. This work revealed the presence of heterogeneity and complexity in the silica phytoliths and the lignified structures in date fruits. It was found that lignin exists independently of silica in the secondary cell walls of parenchymal and sclereid cells and that silica exists independently of lignin in the spheroid phytoliths that surround the sclereid cells. Interestingly, a small proportion of lignin and silica seemed to co-exist as partners in the spiral coils of the tracheid phytoliths.

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