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1.
Nanomaterials (Basel) ; 12(7)2022 Apr 04.
Artículo en Inglés | MEDLINE | ID: mdl-35407322

RESUMEN

The objective of the present research is to obtain enhanced heat and reduce skin friction rates. Different nanofluids are employed over an exponentially stretching surface to analyze the heat transfer coefficients. The mathematical model for the problem has been derived with the help of the Rivilin-Erickson tensor and an appropriate boundary layer approximation theory. The current problem has been tackled with the help of the boundary value problem algorithm in Matlab. The convergence criterion, or tolerance for this particular problem, is set at 10-6. The outcomes are obtained to demonstrate the characteristics of different parameters, such as the temperature exponent, volume fraction, and stretching ratio parameter graphically. Silver-water nanofluid proved to have a high-temperature transfer rate when compared with zinc-water and copper-water nanofluid. Moreover, the outcomes of the study are validated by providing a comparison with already published work. The results of this study were found to be in complete agreement with those of Magyari and Keller and also with Lui for heat transfer. The novelty of this work is the comparative inspection of enhanced heat transfer rates and reduced drag and lift coefficients, particularly for three nanofluids, namely, zinc-water, copper-water, and silver-water, over an exponentially stretching. In general, this study suggests more frequent exploitation of all the examined nanofluids, especially Ag-water nanofluid. Moreover, specifically under the obtained outcomes in this research, the examined nanofluid, Ag-water, has great potential to be used in flat plate solar collectors. Ag-water can also be tested in natural convective flat plate solar collector systems under real solar effects.

2.
Sci Rep ; 12(1): 3342, 2022 02 28.
Artículo en Inglés | MEDLINE | ID: mdl-35228602

RESUMEN

The current communication is designed by keeping in the mind high heat transfer capabilities of nanoliquids with the dispersion of diversified-natured nanoparticles in poorly conducting base liquids. Here, an amalgamation of metallic (Cu) and hybridization of metallic and non-metallic oxide (Cu-TiO2) nanoparticles to uplift thermophysical attributes of water is deliberated. The magnetically affected flow between rotating disks under the impact and permeability aspect is assumed. Empirical relations for effective dynamic viscosity, density, and heat capacitance to show mesmerizing features of obliged nanoparticles are also expressed. In addition, mathematical relations also depend on morphological factors like shape, size, and diameter of inducted nanoparticles. The mathematical formulation of the problem is conceded in the form of a system of ODEs after using similarity transformation on dimensional PDEs. Simulations of the complex coupled differential structure are solved by using a numerical approach by employing shooting and Runge-Kutta procedures jointly. The impact of flow concerning variables on associated distributions is revealed through tabular and graphical manner. Quantities of engineering interest associated with work like wall friction and thermal flux coefficients at walls of the disk are also calculated. It is deduced from an examination that the addition of metallic particles raises heat transfer more than non-metallic particles. A significant impression of magnetic field on shear stress is executed by hybrid nanoparticles along the surface of disks. In addition, elevation in Nusselt number and depreciation in skin friction coefficient is revealed against increasing magnitude of nanoparticle volume fraction. A positive trend in skin friction coefficient is manifested against the increasing magnitude of Reynold number. It is also observed that by increasing the size and shape of hybrid nanoparticles thermal conductivity and viscosity of the base fluid increases.


Asunto(s)
Nanopartículas , Fricción , Calor , Nanopartículas/química , Fenómenos Físicos , Conductividad Térmica
3.
Chemosphere ; 288(Pt 2): 132450, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34624353

RESUMEN

Biodiesel commercialization is questionable due to poor brake thermal efficiency. Biodiesel utilization should be improved with the addition of fuel additives. Hydrogen peroxide is a potential fuel additive due to extra hydrogen and oxygen content, which improves the combustion process. In this experimental study, biodiesel has been produced from Jatropha oil employing catalyzed transesterification homogeneously to examine its influence on the performance and emissions at engine loads with 1500 rpm utilizing a four-stroke single-cylinder diesel engine. D60B40 (having 60% diesel and 40% biodiesel) and D60B30A10 (60% diesel, 30% biodiesel and 10% hydrogen peroxide (H2O2)), are the fuel mixtures in the current study. The addition of H2O2 reduces emissions and enhances the combustion process. This effect occurred due to the micro-explosion of the injected fuel particles (which increases in-cylinder pressure and heat release rate (HRR)). An increase of 20% in BTE and 25% reduction in BSFC for D60B30A10 was observed compared to D60B40. Significant reduction in emissions of HC up to 17.54%, smoke by 24.6% CO2 by 3.53%, and an increase in NOx was noticed when the engine is operated with D60B30A10. The HRR increased up to 18.6%, ID reduced by 10.82%, and in-cylinder pressure increased by 8.5%. Test runs can be minimized as per Taguchi's design of experiments. It is possible to provide the estimates for the full factorial design of experiments. Exhaust gas temperature standards are evaluated and examined for all fuel blends.


Asunto(s)
Biocombustibles , Peróxido de Hidrógeno , Proyectos de Investigación
4.
Chemosphere ; 286(Pt 3): 131835, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34426273

RESUMEN

This paper proposed to interpret the novel method of extracellular polymeric substance (EPS) removal in advance to sludge disintegration to enrich bioenergy generation. The sludge has been subjected to deflocculation using Zinc oxide/Chitosan nanocomposite film (ZCNF) and achieved 98.97% of solubilization which enhance the solubilization of organics. The obtained result revealed that higher solubilization efficiency of 23.3% was attained at an optimal specific energy of 2186 kJ/kg TS and disintegration duration of 30 min. The deflocculated sludge showed 8.2% higher solubilization than the flocculated sludge emancipates organics in the form of 1.64 g/L of SCOD thereby enhancing the methane generation. The deflocculated sludge produces methane of 230 mL/g COD attained overall solid reduction of 55.5% however, flocculated and control sludge produces only 182.25 mL/g COD and 142.8 mL/g COD of methane. Based on the energy, mass and cost analysis, the deflocculated sludge saved 94.1% of energy than the control and obtained the net cost of 5.59 $/t which is comparatively higher than the flocculated and control sludge.


Asunto(s)
Quitosano , Nanocompuestos , Óxido de Zinc , Anaerobiosis , Análisis de la Demanda Biológica de Oxígeno , Conservación de los Recursos Energéticos , Matriz Extracelular de Sustancias Poliméricas , Floculación , Metano , Aguas del Alcantarillado , Eliminación de Residuos Líquidos
5.
Sci Total Environ ; 802: 149750, 2022 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-34454158

RESUMEN

The continuous growing demand for fossil fuel puts an enormous pressure on finding a better replacement. This research paper explores the detailed information on the improved production, emission and performance characteristics of the distinct bio-oil derived from the micro algae of Schizochytrium. The algae were grown in the artificial seawater with enough nitrogen supply at the required standard conditions. The lipid growth and production of the bio-oil were monitored closely and measured. Different fuel blends were used at different concentrations as B0 (100% Diesel), B10 (10% schizochytrium biofuel +90% diesel), B20 (20% schizochytrium biofuel +80% diesel) and B30 (30% schizochytrium biofuel +70% diesel). A small single cylinder, four stroke diesel engine was used to conduct the tests. All tests were conducted at different speed conditions of 1200 rpm to 2100 rpm in six intervals. The performance qualities of bio-oil such as CO, NOX, and smoke and CO2 emission along with the performance qualities of brake thermal efficiency and brake specific fuel consumption. Form the results, the Schizochytrium microalgae bio-oil as the bio fuel for diesel engines in the moderate level showed the improved performance by increasing the BTE and reducing the harmful gas emissions except NOX. However, the emission level of NOX was slightly higher than the diesel emitted value. The difference between them was negligible.


Asunto(s)
Biocombustibles , Gasolina , Monóxido de Carbono/análisis , Transferencia de Energía , Óxidos de Nitrógeno/análisis , Emisiones de Vehículos
6.
Sci Total Environ ; 808: 151969, 2022 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-34843758

RESUMEN

Different CO2 concentration such as 0.03, 5, 10 and 15% and low-cost urea repletion/starvation in Chlorella vulgaris on growth, total and non-polar lipid content and fatty acid composition was studied. Chlorella vulgaris grown at 0.03% CO2 apparently revealed inferior biomass yield 0.55 g/L on 14th day compared to CO2 supplemented cells. In the case of CO2 supply, 15% CO2 has unveiled higher biomass yield at about 1.83 g/L on day 12 whereas biomass yield for 5 and 10% CO2 supplemented cells was 1.61 and 1.73 g/L, respectively on 12th day of cultivation. The biomass productivity (g) per liter per day was 32 mg in control condition whereas it was 125, 134 and 144 mg/L/d in 5, 10 and 15% CO2 supplied cells, respectively. Lipid content of the strain grown at control, 5, 10 and 15% CO2 was 21.2, 22.1, 23.4 and 24.6%, respectively and however, without CO2 addition in low-cost urea repleted and urea depleted medium grown cells revealed 21.2 and 24.2%, respectively. Interestingly, strain grown at 15% CO2 supply in urea deplete medium yielded 28.7% lipid and contribution of non-polar lipids in total lipids is 69.7%. Further, the fatty acid composition of the strain grown in 15% CO2 supply in urea depleted medium showed C16:0, C16:1, C18:1 and C18:3 in the level of 30.12, 9.98, 23.43, and 11.97%, respectively compared to control and urea amended condition.


Asunto(s)
Chlorella vulgaris , Microalgas , Benchmarking , Biocombustibles , Biomasa , Dióxido de Carbono , Ácidos Grasos , Lípidos , Urea
7.
Environ Res ; 205: 112509, 2022 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-34871596

RESUMEN

Environmental concerns have initiated the search for greener measures to mitigate pollution issues. Bio Nano CaO was synthesized by reducing CaO extracted from chicken egg shell using tea decoction. The synthesized material was characterized by physico-chemical techniques such as XRD, TGA, BET surface area analyser, TGA and SEM techniques. XRD studied confirmed the crystalline nature of material. The prepared material was found to be stable till 450 οC from TGA study. The SEM pictures displayed uniform and discrete particles which portrays the high probable sites that maximises the catalytic activity. The optimization of microwave assisted Biodiesel synthesis from chicken feather oil through Transesterification process using the bio-synthesized catalytic material was the main aim of the study. A 500 W microwave irradiation of Chicken feather meal oil using 8:1 Methanol:Oil input, 1% Bio Nano CaO concentration, 5 min of reaction time resulted in 95% conversion of chicken feather meal oil into chicken feather meal methyl esters. The Biodiesel was showed low viscosity (4.15 mm2/s), high heating value (50 MJ/kg), high flash point (153οC), reasonable pour point (12 οC) and good cetane number (50 min). The future works will be concentrated on the engine studies related to Torque, fuel consumption, emission data by using the synthesized Biodiesel.


Asunto(s)
Biocombustibles , Pollos , Animales , Catálisis , Cáscara de Huevo , Plumas , Microondas , Óxidos , Aceites de Plantas/química
8.
Environ Res ; 205: 112474, 2022 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-34863683

RESUMEN

A synergistic catalyst was architectured using the hydrothermal crystallization method. Mesoporous material with pore diameter less than 20 nm was grown on the microporous Zeolite HY. The catalysts were characterized by XRD, ICP-OES, BET, TPD, SEM and TEM techniques. The SEM picture portrayed excellent core - shell morphology and TEM analysis corresponded to the XRD reports. Mahua oil was cracked in a pilot scale reactor over the synthesized catalysts at an optimized reaction condition (Temperature: 400 οC; WHSV: 4.6 h-1). The gaseous and liquid products of reaction were analyzed by Residual Gas analyzer and GCMS respectively. The NMR spectral analysis of fuel showed low traces of aromatics. The produced fuel was analyzed for its significant properties like calorific value, fire point, flash point and viscosity.


Asunto(s)
Ácidos Grasos , Dióxido de Silicio , Catálisis , Dióxido de Silicio/química
9.
Polymers (Basel) ; 13(17)2021 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-34502935

RESUMEN

The effect of crump rubber on the dry sliding wear behavior of epoxy composites is investigated in the present study. Wear tests are carried out for three levels of crump rubber (10, 20, and 30 vol.%), normal applied load (30, 40, and 50 N), and sliding distance (1, 3, and 5 km). The wear behavior of crump rubber-epoxy composites is investigated against EN31 steel discs. The hybrid mathematical approach of Taguchi-coupled Grey Relational Analysis (GRA)-Principal Component Analysis (PCA) is used to examine the influence of crump rubber on the tribological response of composites. Mathematical and experimental results reveal that increasing crump rubber content reduces the wear rate of composites. Composites also show a significant decrease in specific wear values at higher applied loads. Furthermore, the coefficient of friction also shows a decreasing trend with an increase in crump rubber content, indicating the effectiveness of reinforcing crump rubber in a widely used epoxy matrix. Analysis of Variance (ANOVA) results also reveal that the crump rubber content in the composite is a significant parameter to influence the wear characteristic. The post-test temperature of discs increases with an increase in the applied load, while decreasing with an increase in filler loading. Worn surfaces are analyzed using scanning electron microscopy to understand structure-property correlations. Finally, existing studies available in the literature are compared with the wear data of the present study in the form of a property map.

10.
Environ Res ; 202: 111647, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34237334

RESUMEN

Semiconductor photocatalysts are efficient degraders of organic and inorganic waste water pollutants. Herein, we synthesized nickel-titanium dioxide (Ni-TiO2) nanoflakes using Mukia maderaspatana leafs with the aim of analyzing their photocatalytic degradation potential. Morphological analyses revealed that the nanoflakes were highly agglomerated with an average size of 100 nm. Further, elemental analysis confirmed the presence of Ti, O, and Ni, whereas Fourier transform infrared spectroscopy and X-ray diffraction established the presence of TiO2 and NiO. We found that photocatalytic degradation of congo red under UV illumination increased with increasing incubation period, demonstrating that Ni-TiO2 nanoflakes can be used as optimal photocatalysts for the degradation of dyes in waste water.


Asunto(s)
Rojo Congo , Níquel , Catálisis , Colorantes , Extractos Vegetales , Titanio , Difracción de Rayos X
11.
Environ Res ; 202: 111699, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34273371

RESUMEN

Leptospirosis is a severe bacterial infectious disease caused by the organisms belonging to the genus of Leptospira. The chitosan/Bacopa saponin/tripolyphosphate (CS/BS/TPP) nanoparticles conjugated with recombinant DNA vaccines were designed against Leptospirosis. Chitosan, a polysaccharide is suitable for delivery of drug, and gene due to its bio-compatible and biodegradable properties. Bacopa saponins are used for the induction of the immune response against microbial infections. The recombinant DNA vaccine construct was composed of the leptospiral outer membrane LipL32 gene tagged with EGFP and hGMCSF adjuvant in the pVAX1 mammalian expression vector along with the Cytomegalovirus (CMV) promoter. These recombinant DNA vaccine constructs was termed as pVAX1-EGFP-LipL32 and pVAX1-EGFP-hGMCSF-LipL32, and these constructs were conjugated with CS/BS/TPP nanoparticles by using the ionic gelation technique. Thus, CS/BS/TPP conjugated nanoparticle DNA vaccine was confirmed by functionality (FT-IR), crystalline nature (XRD) and surface charge (Zeta potential). The 90% encapsulation efficiency was observed in the conjugated nanoparticle DNA vaccine. In contrast, cell viability analysis validated that the synthesized DNA conjugated CS/BS/TPP nanoparticles showed low cytotoxicity up to 10 mg/mL. The results showed here are the initial establishment of DNA vaccine conjugated nanoparticles, which can be used as a potential anti-leptospiral vaccine.


Asunto(s)
Bacopa , Quitosano , Leptospirosis , Nanopartículas , Saponinas , Animales , Técnicas de Transferencia de Gen , Espectroscopía Infrarroja por Transformada de Fourier
12.
Environ Res ; 201: 111502, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34214561

RESUMEN

The mycofabricated metal nanoparticles (NPs) plays a significant role in cancer therapeutics and imparts a strategy in medicine. The current investigation focused to synthesize the Copper Oxide Nanoparticles (CuONPs) using an endophytic fungus isolated from Aegle marmelosa medicinal tree located in Western Ghats, India. The endophytic fungus FCBY1 explored the highest antagonistic and antioxidant activities among the 16 pigmented endophytic fungal strains which were isolated from the collected samples. The fungus FCBY1 was identified for its morphological and molecular characteristics where the (Internal Transcribed Spacer) ITS 1, 5.8 ribosomal gene and ITS 2 were sequenced; and the organism FCBY1 is Aspergillus terreus. The endophyte was put through for the synthesis of CuONPs and the size and structure of the synthesized particles were characterized by Scanning Electron Microscope (SEM). The confirmation of the CuONPs was characterized by FT-IR, EDAX and XRD analyses. The CuONPs exhibited the maximized antibacterial and antifungal activities against the human clinical pathogens; moreover the particles also explicated the free radicals/ROS scavenging at minimum concentration, which was assessed through DPPH, nitric oxide radical scavenging assays, and reductive power ability. The anti-cancer activity of CuONPs on colon cancer cell lines (HT-29) was evaluated by MTT (IC50: 22 µg/mL) and FACS analyses (32.11% cells gated in S phase of cell cycle). Angiogenesis inhibition in tumor cells was estimated through in vivo HET- CAM assessment and the highest concentration 60 µL tested inhibited the blood vessels at the percentage of 31.36% and 81.81%. The CuONPs explicated the anti-cancer activities in a concentration - dependent manner and the results of this investigation manifest the significant role of the CuONPs in cancer therapeutics.


Asunto(s)
Cobre , Nanopartículas del Metal , Aspergillus , Hongos , Humanos , Pruebas de Sensibilidad Microbiana , Óxidos , Espectroscopía Infrarroja por Transformada de Fourier
13.
Molecules ; 26(14)2021 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-34299410

RESUMEN

Epoxy resins, due to their high stiffness, ease of processing, good heat, and chemical resistance obtained from cross-linked structures, have found applications in electronics, adhesives coatings, industrial tooling, and aeronautic and automotive industries. These resins are inherently brittle, which has limited their further application. The emphasis of this study is to improve the properties of the epoxy resin with a low-concentration (up to 0.4% by weight) addition of Multi-Walled Carbon Nanotubes (MWCNTs). Mechanical characterization of the modified composites was conducted to study the effect of MWCNTs infusion in the epoxy resin. Nanocomposites samples showed significantly higher tensile strength and fracture toughness compared to pure epoxy samples. The morphological studies of the modified composites were studied using Scanning Electron Microscopy (SEM).

14.
Environ Res ; 201: 111520, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34153332

RESUMEN

The pentadentate ligand and the precursors were combined to form complexes by green approach. The ligand formation was confirmed by UV-Vis, FT-IR, 1H-NMR, and LC-MS. The optimised stable structure was obtained by molecular simulation studies and the complexes were interpreted by conductivity measurements, UV-Vis, FT-IR, magnetic susceptibility, VSM, and ESR spectral studies. The redox nature of the complexes was investigated by cyclic voltammetry. The cyclic voltammogram shows complexes exhibited single electron transfer from Cu+2/Cu+1. Complexes and penta-dentate ligand were screened for in vitro cytotoxicity by MTT assay method on A431 skin cancer cell line. The ligand structural stability and biological activity were confirmed by theoretical computational studies. The magnetic behaviour showed antiferromagnetic properties at low temperature. The complexes were used as high bar magnets. Similarly, the redox behaviour showed that the complexes could be used in electroplating techniques and sensors. Clinical application revealed that the complexes had effective cytotoxicity. From the data obtained, the complexes were in the form [MLR], where L was the penta-dentate ligand and R = [C6H5COO] & R = [C6H4COO (OH)].


Asunto(s)
Complejos de Coordinación , Línea Celular , Cobre , Células Epidérmicas , Humanos , Espectroscopía Infrarroja por Transformada de Fourier
15.
Environ Res ; 201: 111594, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34186080

RESUMEN

This research was aimed to evaluate the phytochemical profile, bactericidal activity of Hygrophila spinosa against multidrug resistant Pandoraea sputorum and assess their antioxidant competence against various radicals and studied their hepatoprotective and nephroprotective activity on HepG2 and HEK 293 cell line. The results showed that the methanol extract has various phytochemical components with reasonable quantity. Fortunately, the multidrug-resistant P. sputorum was sensitive (22.8 ± 0.2 mm of the zone of inhibition) at 15 mg mL-1 concentration of methanol extract. The higher concentration of phenolic and other phytochemical components, showed significant antioxidant activity against ferric, DPPH, hydroxyl, and ABTS radicals, with IC50 values of 71.09, 64.333, 91.157, and 104.931 g mL-1, respectively. Surprisingly, the methanol extract possesses hepato and nephroprotective activity against CCl4 and cisplatin-induced cytotoxicity on HepG2 and HEK 293 cell lines, respectively. It maintains the cell viability as up to 90.48% and 90.35% of HepG2 and EK 293 cell line at the concentration of 20 µg mL-1. The FTIR analysis states that the methanol extract possesses a significant functional group responsible for these multi-potential activities. These results suggest that, the methanol extract of H. spinosa might contain the most significant bioactive components with outstanding medicinal properties.


Asunto(s)
Acanthaceae , Antibacterianos , Burkholderiaceae/efectos de los fármacos , Extractos Vegetales , Sustancias Protectoras/farmacología , Acanthaceae/química , Antibacterianos/farmacología , Farmacorresistencia Bacteriana Múltiple , Células HEK293 , Células Hep G2 , Humanos , Riñón/efectos de los fármacos , Hígado/efectos de los fármacos , Metanol , Extractos Vegetales/farmacología
16.
Chemosphere ; 279: 130632, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34134423

RESUMEN

The accumulated bauxite mine soil had an acidic pH of 5.52 ± 0.12 and more heavy metals such as Cr, Cd, Zn, and Pb, which can cause severe soil and water pollution to the nearby farmlands and water reservoirs. Hence, the work was designed to find the possibility of reclamation of bauxite mine soil through Crotalaria juncea with the amalgamation of native metal degrading bacterial isolates. Out of 15 bacterial cultures, only 2 isolates (B3 and B14) showed excellent metal tolerance (for up to 750 mg L-1), solubilizing (15.27-38.7 mg kg-1) (including phosphate: 47.4 ± 1.79%), and degrading potential (22.8 ± 0.89 to 31.5 ± 1.6%) than the others. These B3 and B14 isolates were recognized as B. borstelensis UTM105 (1432 bp) and B. borstelensis AK2 (1494 bp) through molecular characterization. These isolates have produced a metal stress response protein (205-43 KDa molecular weight protein) during metal stress conditions. The phytoremediation competence of C. juncea under the influence of these bacterial isolates was assessed with various treatment (I-IV) schemes. The treatment IV (C. juncea with two bacterial isolates) showed substantial physiological and biochemical results compared with the control and the other treatments. The phytoremediation competence of C. juncea was also effective in treatment IV than the others. It reduced and extracted a reasonable quantity of metals from the bauxite mine soil. The intact results accomplished that these native metals tolerant, solubilizing, and degrading bacterial isolates, could be used as optimistic bacterial candidates in combination with C. juncea for the effective reclamation of metal enriched bauxite mine soil.


Asunto(s)
Crotalaria , Metales Pesados , Contaminantes del Suelo , Óxido de Aluminio , Bacterias , Biodegradación Ambiental , Metales Pesados/análisis , Planta de la Mostaza , Suelo , Contaminantes del Suelo/análisis , Instalaciones de Eliminación de Residuos
17.
Environ Res ; 200: 111493, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34129868

RESUMEN

The present research work reports the biosynthesis of hydroxyapatite (HAp) from eggshells and green synthesis of HAp from eggshells with incorporation of Piper betel leaf extract (PBL-HAp) using microwave conversion method. Although there are several works on synthesis of HAp from eggshells and other calcium and phosphorus rich substrates, the incorporation of herbal extract with HAp to promote antimicrobial and antibiofilm activity is less explored and reported. This research work highlights a simple and cost-effective method for development of antimicrobial biomaterials by combining the concepts of waste management, biomaterial science, and herbal medicine. In the present study, characterization of synthesized HAp was applied by X-ray Diffraction (XRD), Fourier Transform Infrared (FTIR) spectroscopy, Proton Nuclear Magnetic Resonance (1H NMR) spectroscopy, and morphological analysis using Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM). The characterization results indicated that the prepared HAp and PBL-HAp were pure b-type carbonated HAp. The PBL-HAp was checked for its antibacterial activity using the well diffusion method and biofilm inhibitory activity by crystal violet assay against some common pathogens. The antibacterial activities against Staphylococcus aureus and biofilm inhibitory activities against Escherichia coli, Vibrio harveyi, Pseudomonas aeruginosa, and Staphylococcus aureus of Piper betel leaf extract coated HAp (PBL-HAp) were showed to be significant and offered a promising role for the development of potent dental biomaterials.


Asunto(s)
Durapatita , Piper , Animales , Antibacterianos/farmacología , Biopelículas , Cáscara de Huevo , Extractos Vegetales/farmacología , Espectroscopía Infrarroja por Transformada de Fourier , Vibrio , Difracción de Rayos X
18.
Environ Res ; 200: 111333, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34051198

RESUMEN

The frequent application of synthetic insecticides creates resistance among insects, including mosquitoes, and causes environmental pollution and health issues. The current work aim at assessing the possibilities to produce and characterize the titanium dioxide (TiO2) nanoparticles (TiO2 NPs) mediated through the aqueous leaf extract of Pouteria campechiana, and their larvicidal and pupicidal activities against Aedes aegypti. The attained results showed that the aqueous leaf extract of P. campechiana had the efficiency to fabricate TiO2 NPs from TiO2. Under the UV-vis spectrum analysis, a sharp peak was recorded at 320 nm, which indicated the production of TiO2 NPs by the plant extract. The SEM analysis revealed that the synthesized TiO2 NPs were spherical, and 5 dissimilar diffractions were detected in the XRD spectrum analysis related to the TiO2 NPs. In FTIR analysis, a prominent peak was found at 1052.41 cm-1, corresponding to alcohol, and confirmed metal reduction. In the EDX analysis, there was a signal of around 58.44%, confirming the decrease in Ti from TiO2 NPs, and the remaining percentages were Ca, Al, and Mg. About 900 µg mL-1 of TiO2 NPs had excellent lethal activity against various larvae and pupa stages of Ae. aegypti. The attained results showed that the P. campechiana aqueous leaf extract could reduce TiO2 into TiO2 NPs and could be considered a mosquito control agent. Furthermore, this is the initial report about the aqueous leaf extract of P. campechiana effectively synthesizing the TiO2 NPs with anti-mosquito activity.


Asunto(s)
Aedes , Nanopartículas del Metal , Pouteria , Animales , Nanopartículas del Metal/toxicidad , Extractos Vegetales/farmacología , Plata , Titanio
19.
Environ Res ; 200: 111335, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34051200

RESUMEN

The frequent applications of synthetic chemical insecticides and drugs create resistance among insects and microbes, creating a new threat to human and environmental welfare. This investigation focused on evaluating the possibilities of fabricating and characterizing the titanium dioxide nanoparticles (TiO2 NPs) from titanium dioxide (TiO2) through the aqueous leaf extract of Coleus aromaticus. Their biological applications were studied against the larvae of Aedes aegypti human pathogenic bacteria, and cancer cell line. The results revealed that the aqueous leaf extract had the metal reducing proficiency to produce nanoparticles from TiO2. The synthesized TiO2 NPs were initially confirmed by visible color changes and Ultraviolet-Visible Spectrophotometer analysis that showed a predominant peak at 332 nm. Furthermore, the nanocrystals, structural alignment, functional groups and elemental compositions were studied by following standard operating protocol in XRD (X-ray Powder Diffraction), FTIR (Fourier Transform Infrared Spectroscopy), TEM (Transmission Electron Microscopy), and EDX (Energy-Dispersive X-ray Spectroscopy) techniques, respectively. The results attained from these techniques confirmed that the plant mediated and fabricated particles were in the nanoscale range (12-33 nm) with a hexagonal shape. The synthesized TiO2 NPs had an outstanding (1000 µg mL-1) larvicidal activity against the four stages of instars larvae of Ae. aegypti at 1000 µg mL-1. It also had an excellent antibacterial potential against E. faecalis (33 mm), followed by S. boydii (30 mm) at 30 mg L-1 concentration. The green fabricated TiO2 NPs had a fabulous (92.37%) cytotoxic activity on the HeLa cell line at 100 µg mL-1 dosage within one day of exposure. The entire results concluded that the C. aromaticus mediated TiO2 NPs have excellent biological applications and thus, could be considered for the welfare of human beings.


Asunto(s)
Coleus , Insecticidas , Nanopartículas del Metal , Animales , Antibacterianos/toxicidad , Células HeLa , Humanos , Larva , Nanopartículas del Metal/toxicidad , Extractos Vegetales/farmacología , Hojas de la Planta , Espectroscopía Infrarroja por Transformada de Fourier , Titanio , Difracción de Rayos X
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