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1.
Int J Biol Macromol ; 268(Pt 1): 131600, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38631575

RESUMO

Hereunder, we pioneered the synthesis of Copper Oxide nanoparticles (CuO NPs) utilizing Tragacanth gum (TG). The NPs were characterized using advanced techniques and assessed for different pharmaceutical and environmental perspectives. The successful formation of a colloidal NPs solution was confirmed by the appearance of a distinct black color and a distinct peak at 260 nm in UV-Visible spectrophotometry. The FTIR analysis unveiled a spectrum of functional groups responsible for the reduction and stabilization of CuO NPs. Dynamic Light Scattering (DLS) and Transmission Electron Microscopy (TEM) revealed size of NPs as 36.24 nm and 28 ± 04 nm respectively. Energy Dispersive X-ray (EDX) Analysis indicated weight percentages of 70.38 % for Cu and 18.88 % for O, with corresponding atomic percentages. The X-ray Diffraction (XRD) analysis revealed the orthorhombic crystal structure of the prepared CuO NPs. Antimicrobial assessments through disc-diffusion assays demonstrated significant zones of inhibition (ZOI) against gram-positive bacterial strains (Bacillus Halodurans and Micrococcus leutus) and a gram-negative bacterial strain (E. coli). Against the fungal strain Aspergillus niger, a ZOI of 18.5 ± 0.31 mm was observed. The NPs exhibited remarkable antioxidant potential determined through 2,2-Diphenyl-1-picrylhydrazyl (DPPH) and H2O2 scavenging assays. At a concentration of 3 mg/mL, the NPs demonstrated biofilm inhibition rates of 96 %, 90 %, 89.60 %, and 72.10 % against Micrococcus luteus, Bacillus halodurans, MRSA and E.coli respectively. Furthermore, the CuO NPs showed a high photocatalytic potential towards the degradation of safranin dye under sunlight irradiation. In conclusion, the findings underline the promising multifunctional properties of TG-based CuO NPs for different practical applications.


Assuntos
Biofilmes , Cobre , Nanopartículas Metálicas , Tragacanto , Cobre/química , Tragacanto/química , Biofilmes/efeitos dos fármacos , Catálise , Nanopartículas Metálicas/química , Anti-Infecciosos/farmacologia , Anti-Infecciosos/química , Testes de Sensibilidade Microbiana , Antibacterianos/farmacologia , Antibacterianos/química , Aspergillus niger/efeitos dos fármacos , Processos Fotoquímicos
2.
Int J Biol Macromol ; 252: 126215, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37572806

RESUMO

Hereunder, for the first time, we reported phytocompounds in the methanolic extract of Acacia modesta (AM) gum through Gas chromatography-mass spectrometry (GS-MS). Further, the AM gum aqueous solution was used for gold nanoparticles (AuNPs) synthesis through a simple, swift, eco-friendly, and less costly green synthesis approach. A total of 108 phytocompounds (63 with nonpolar, 45 with polar column) were identified in the gum extract, which includes fatty acids, alcohols, sterols, aldehyde/ketones, furans, aromatic compounds, esters, phenols, terpenes, sugar derivatives, alkaloids, and flavones. From three used concentrations (5, 10, and 15 mg/mL) of the AM gum aqueous solution, the 15 mg/mL gum solution resulted in more successful AuNP synthesis with a smaller size, which was visualized by a rusty red color appearance. UV-Visible absorption spectroscopy revealed the characteristic surface plasmon resonance (SPR) of AuNPs in aqueous solution at 540 nm. Dynamic light scattering (DLS) measurement of NPs solution revealed a hydrodynamic diameter of 162 ± 02 nm with the highest gum concentration where core AuNPs diameter was 22 ± 03 nm, recorded by Transmission electron microscopy. Zeta potential revealed fair stability of AuNPs that was not decreased with time. Catalytic activity experiments revealed that AM gum-based AuNPs can increase the rate of the reduction of methylene blue 10 times in comparison with AM gum extract alone. Results from this study showed that a diverse array of phytocompounds in AM gum can successfully reduce gold ions into gold nanoparticles, which can be used further in different pharmaceutical and industrial applications.


Assuntos
Acacia , Nanopartículas Metálicas , Ouro , Metanol , Cromatografia Gasosa-Espectrometria de Massas , Nanopartículas Metálicas/química , Química Verde/métodos , Extratos Vegetais/química
3.
Pharmacol Biochem Behav ; 217: 173388, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35447158

RESUMO

Age-related cognitive decline and disruptions in circadian rhythms are growing problems as the average human life span increases. Multiple strains of the senescence-accelerated mouse (SAM) show reduced life span, and the SAMP8 strain in particular has been well documented to show cognitive deficits in behavior as well as a bimodal pattern of circadian locomotor activity. However, little is known about circadian regulation within the hippocampus of these strains of mice. Here we test the hypothesis that in this early senescence model, disruption of the molecular circadian clock in SAMP8 animals drives disrupted behavior and physiology. We found normal rhythms in PER2 protein expression in the SCN of SAMP8 animals at 4 months, despite the presence of disrupted wheel-running activity rhythms at this age. Interestingly, a significant rhythm in PER2 expression was not observed in the hippocampus of SAMP8 animals, despite a significant 24-h rhythm in SAMR1 controls. We also examined time-restricted feeding as a potential strategy to rescue disrupted hippocampal plasticity. Time-restricted feeding increased long-term potentiation at Schaffer collateral-CA1 synapses in SAMP8 mice (compared to SAMR1 controls). Overall, we confirm disrupted circadian locomotor rhythms in this early senescence model (as early as 4 months) and discovered that this disruption is not due to arrhythmic PER2 levels in the SCN; however, other extra-SCN circadian oscillators (i.e., hippocampus) are likely impaired with accelerated aging.


Assuntos
Ritmo Circadiano , Hipocampo , Envelhecimento/fisiologia , Animais , Ritmo Circadiano/fisiologia , Modelos Animais de Doenças , Potenciação de Longa Duração , Masculino , Camundongos
4.
Int J Biol Macromol ; 204: 466-475, 2022 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-35157899

RESUMO

In the present research, we developed zinc oxide nanoparticles (ZnO-NPs) based surgical sutures for the accelerated wound healing process. Color change from transparent to dark, surface plasmon response with a peak at 270 nm and infra-red spectra with ZnO-bond stretches at 489.6831 cm-1 confirmed the synthesis of NPs. Rod shape ZnO-NPs with an ideal size of 70 ± 03 nm were noted with uniform distribution. X-rays diffraction patterns revealed sharp peaks which was a clear indication of the crystalline nature of NPs. The energy dispersive X-ray analysis of synthesized nanoparticles reveals that the expected stoichiometric mass percent of zinc and oxygen is 77.55% and 22.45% respectively. Disc-diffusion antibacterial assay revealed that synthesized NPs hold good anti-bacterial potential against the Escherichia coli and Methicillin-resistant staphylococcus aureus (MRSA). Gum based ZnO-NPs coated suture revealed good tensile strength which is considered as a necessary parameter for suturing purposes. The designed suture showed excellent wound healing potential in Sprague-dawley rats through the incision wound model. Overall, in rats, rapid rate of epithelialization, wound contraction, mild inflammation and absence of any infection on the wounded site were recorded. Additionally, histopathology showed enhanced collagen fibers, fibroblast cells, lower inflammatory cells and rapid angiogenesis at healed tissues as compared to standard surgical treatment. Conclusively, the improved wound healing responses of the AM-ZnO-NPs were obtained due to the higher antibacterial activity of NPs.


Assuntos
Nanopartículas Metálicas , Staphylococcus aureus Resistente à Meticilina , Óxido de Zinco , Animais , Antibacterianos/química , Química Verde , Goma Arábica , Nanopartículas Metálicas/química , Testes de Sensibilidade Microbiana , Extratos Vegetais/química , Ratos , Suturas , Cicatrização , Óxido de Zinco/química , Óxido de Zinco/farmacologia
5.
Environ Res ; 208: 112644, 2022 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-34979127

RESUMO

Surfactant stabilized Gold (Au) nanomaterials (NMs) have been documented extensively in recent years for numerous sensing applications in the academic literature. Despite the crucial role these surfactants play in the sensing applications, the comprehensive reviews that highlights the fundamentals associated with these assemblies and impact of these surfactants on the properties and sensing mechanisms are still quite scare. This review is an attempt in organizing the vast literature associated with this domain by providing critical insights into the fundamentals, preparation methodologies and sensing mechanisms of these surfactant stabilized Au NMs. For the simplification, the surfactants are divided into the typical and advanced surfactants and the Au NMs are classified into Au nanoparticles (NPs) and Au nanoclusters (NCs) depending upon the complexity in structure and size of the NMs respectively. The preparative methodologies are also elaborated for enhancing the understanding of the readers regarding such assemblies. The case studies regarding surfactant stabilized Au NMs were further divided into colorimetric sensors, surface plasmonic resonance (SPR) based sensors, luminescence-based sensors, and electrochemical/electrical sensors depending upon the property utilized by the sensor for the sensing of an analyte. Future perspectives are also discussed in detail for the researchers looking for further progress in that particular research domain.


Assuntos
Nanopartículas Metálicas , Nanoestruturas , Colorimetria , Ouro/química , Nanopartículas Metálicas/química , Nanoestruturas/química , Tensoativos
6.
Crit Rev Food Sci Nutr ; 62(14): 3913-3929, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-33427482

RESUMO

Naturally occurring plant-based gums and their engineered bio-nanostructures have gained an immense essence of excellence in several industrial, biotechnological, and biomedical sectors of the modern world. Gums derived from bio-renewable resources that follow green chemistry principles are considered green macromolecules with unique structural and functional attributes. For instance, gum mostly obtained as exudates are bio-renewable, bio-degradable, bio-compatible, sustainable, overall cost-effective, and nontoxic. Gum exudates also offer tunable attributes that play a crucial role in engineering bio-nanostructures of interest for several bio- and non-bio applications, e.g., food-related items, therapeutic molecules, sustained and controlled delivery cues, bio-sensing constructs, and so on. With particular reference to plant gum exudates, this review focuses on applied perspectives of various gums, i.e., gum Arabic, gum albizzia, gum karaya, gum tragacanth, and gum kondagogu. After a brief introduction with problem statement and opportunities, structural and physicochemical attributes of plant-based natural gums are presented. Following that, considerable stress is given to green synthesis and stabilization of gum-based bio-nanostructures. The final part of the review focuses on the bio- and non-bio related applications of various types of gums polysaccharides-oriented bio-nanostructures.


Assuntos
Nanoestruturas , Tragacanto , Goma Arábica/química , Gomas Vegetais , Polissacarídeos , Tragacanto/química
7.
Braz. J. Pharm. Sci. (Online) ; 58: e18745, 2022. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1374549

RESUMO

Abstract The present study aimed to compare the crude, modified and hydrolyzed gums of Dalbergia sissoo and Acacia modesta as a biodegradable binder for drug delivery system using acetaminophen as a model drug. The physiochemical properties such as pH, fluorescence analysis and swelling index were determined. The gums were hydrolyzed and modified. Acetaminophen tablets were prepared using wet granulation technique and the gum solutions were used as a binder. Hydroxypropyl methylcellulose was used as a synthetic binder. Different properties of granules and tablets were evaluated. Results showed that both gums were acidic in nature, while D. sissoo and A. modesta showed light brown and creamy color in fluorescence analysis. The swelling ratio was the highest in water followed by 0.1N HCl and least in phosphate buffer. The prepared tablets showed faster and slower dissolution profiles in the same dissolution system. The crude gums have the highest dissolution rate, and this rate was decreased in the case of modified and hydrolyzed gums samples. The crude gums showing slower release can be useful in sustained-release tablets, while the modified gums having faster release rate are helpful in conventional tablet formulation. Taken together, the selected gums could be a good model for evaluation as a binder or hydrophilic polymer in tablet formulation.

8.
Int J Biol Macromol ; 191: 861-871, 2021 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-34571126

RESUMO

Compressed tablet formation from granular drug require binder with Cohesiveness property. Plants mucilage as pharmaceutical excipients are available. In this study, biocompatible date palm mucilage was encapsulated with silver nano particles for sustained drug release to provoke an immune response. Nano formulated mucilage was characterized by UV/VIS, FTIR, XRD, SEM/EDX spectrophotometry. UV/VIS spectra revealed an intense surface plasmon resonance peak at 406 nm for spherical mono dispersed silver nano formulated mucilage resulted from efficient reduction of silver ions to AgNPs. Zeta sizer disclosed the emergence of single peak at 139.7 nm with 100% intensity. Crude mucilage exhibited number of peaks in the region of 4000-500 cm-1 by FT-IR spectroscopy whereas purified as well as nano formulated samples showed somewhat different pattern of peaks in addition to peaks of crude sample. XRD spectra of crude mucilage revealed somewhat regular pattern while purified and modified mucilage displayed irregular structure. In SEM analysis, crude mucilage was appeared as granular that turned into porous network with entangled tiny silver nano spheres. A controlled release of drug levofloxacin hemihydrate was evaluated using crude/ nano formulated mucilage as excipient. Nano formulated mucilage delayed the onset exposure of drug in gastric medium giving recommendations as value added bio binder for drug to the target organ.


Assuntos
Liberação Controlada de Fármacos , Nanopartículas/química , Mucilagem Vegetal/química , Antibacterianos/administração & dosagem , Células Cultivadas , Colo/metabolismo , Humanos , Levofloxacino/administração & dosagem , Phoeniceae/química
9.
Biomater Res ; 25(1): 17, 2021 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-33964968

RESUMO

BACKGROUND: Herein, we first time used the gum Moringa oleifera as reducing and capping agent for successful synthesis of silver nitrate and zinc oxide nanoparticles(NPs) through green synthesis approach. This study was aimed to check antibacterial activities of synthesized NPs against multidrug resistant bacteria methicillin-resistant Staphylococcus aureus (MRSA). METHODS: Aqueous solutions of AgNO3 and purified gum powder were mixed with 1:1 ratio, autoclaved at 120oC for 2 min. NPs pellet collected after centrifugation at 10,000 g for 20 min. ZnO NPs were prepared by mixing purified gum powder and metal salt with1:1 ratio, heated (70oC) and stirred at 100 rpm for 4 h followed by centrifugation at 10,000 g for 20 min. Pellet was washed and calcinated at 400oC for 4 h. Antibacterial potential against E. coli, S. aureus and methicillin-resistant Staphylococcus aureus (MRSA) was assessed by widely used Kirby-Bauer antibiotic susceptibility test. RESULTS: Optical observation of colour change from transparent to dark and UV-Visible analysis confirmed the synthesis of NPs. Fourier transform infrared spectroscopy (FTIR) of prepared nonmaterial revealed the characteristic AgNPs and ZnO stretch vibrations at wave number of 523 cm- 1 and 471 cm- 1resectively. Crystalline nature of AgNPs and ZnO NPs was confirmed by x-ray diffraction pattern with clear sharp Peaks. Scanning electron microscopy (SEM) revealed good surface morphology of AgNPs and ZnO NPs with 50nm and 60nm size respectively. AgNPs and ZnO NPs exhibited excellent antibacterial activity against E. coli (with zone of inhibition of 21 ± 02mm and 22 ± 03mm) and S.aureus ( with zone of inhibition of 20 ± 03mm and 21 ± 02mm) while good activity was observed against "super bug" methicillin-resistant Staphylococcus aureus (MRSA) with 16 ± 03mm ad 17 ± 02mm zone if inhibitions respectively. CONCLUSIONS: This novel addition of Moringa Gum based nanoparticles will open new dimensions in the field of nanomedicine and pharmaceutics especially against MDR bacterial strains.

10.
Case Stud Chem Environ Eng ; 2: 100047, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38620566

RESUMO

Currently, the emergence of a novel coronavirus, referred to as SARS-CoV-2, has become a global health concern which cause severe respiratory tract infections in humans. Person-to-person transmission of SARS-CoV-2 has occurred across the globe, within a short period of SARS-CoV-2 emergence. The goal of this analysis is to summarize in various inanimate surfaces and environments information about the frequency, persistence, potential dissemination, and infectivity of SARS-CoV-2. Most respiratory viruses, including coronaviruses, SARS-CoVs, or influenza may persist for a few days on the surfaces or objects. The length of tenacity on various inanimate surfaces depends on the environmental and growth conditions and overall survival rate could range from minutes to month time. The SARS-CoV-2 may survive and maintain infectivity in the air in unventilated buses for 30 â€‹min. As no specific vaccines or therapeutic drugs are available for this contagious virus, timely prevention measures would be crucial to control the future outbreak of this infectious disease. Precautionary strategies such as wearing masks and frequent washing hands are effective to mitigate COVID-19. Following careful consideration of the above-mentioned scenarios, the short review spotlights the pressing environmental issues regarding the persistence, transmission, and infectivity of SARS-CoV-2 in different environmental matrices. Aiming to address this issue with further and deeper insight into the SARS-CoV-2 emergence, a list of most concerned questions is given that should be carefully considered and answered in future studies.

11.
Neurobiol Dis ; 114: 194-200, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29540298

RESUMO

Disruption of circadian rhythms is commonly reported in individuals with Alzheimer's disease (AD). Neurons in the primary circadian pacemaker, the suprachiasmatic nucleus (SCN), exhibit daily rhythms in spontaneous neuronal activity which are important for maintaining circadian behavioral rhythms. Disruption of SCN neuronal activity has been reported in animal models of other neurodegenerative disorders; however, the effect of AD on SCN neurophysiology remains unknown. In this study we examined circadian behavioral and electrophysiological changes in a mouse model of AD, using male mice from the Tg-SwDI line which expresses human amyloid precursor protein with the familial Swedish (K670N/M671L), Dutch (E693Q), Iowa (D694N) mutations. The free-running period of wheel-running behavior was significantly shorter in Tg-SwDI mice compared to wild-type (WT) controls at all ages examined (3, 6, and 10 months). At the SCN level, the day/night difference in spike rate was significantly dampened in 6-8 month-old Tg-SwDI mice, with decreased AP firing during the day and an increase in neuronal activity at night. The dampening of SCN excitability rhythms in Tg-SwDI mice was not associated with changes in input resistance, resting membrane potential, or action potential afterhyperpolarization amplitude; however, SCN neurons from Tg-SwDI mice had significantly reduced A-type potassium current (IA) during the day compared to WT cells. Taken together, these results provide the first evidence of SCN neurophysiological disruption in a mouse model of AD, and highlight IA as a potential target for AD treatment strategies in the future.


Assuntos
Doença de Alzheimer/genética , Doença de Alzheimer/fisiopatologia , Ritmo Circadiano/fisiologia , Locomoção/fisiologia , Núcleo Supraquiasmático/fisiologia , Animais , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Técnicas de Cultura de Órgãos
12.
Int J Biol Macromol ; 84: 236-45, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26709145

RESUMO

Dalbergia sissoo gum was purified by ethanol precipitation. The purified gum was modified and hydrolyzed. Gum was modified by performing polyacrylamide grafting and carboxymethylation methods. The hydrolysis was carried out by using mannanase, barium hydroxide and trifluoroacetic acid. The modified and hydrolyzed gums were characterized using thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) and scanning electron microscopy (SEM). The decrease in viscosity was studied by performing the flow test. The modified and hydrolyzed gums were thermally stable as compared to crude gum. There was increase in crystallinity after modification and hydrolysis, determined through XRD. FTIR analysis exhibits no major transformation of functional group, only there was change in the intensity of transmittance. It is concluded that the modified and hydrolyzed gum can be used for pharmaceutical and food industry.


Assuntos
Dalbergia/química , Estrutura Molecular , Gomas Vegetais/química , Reologia , Varredura Diferencial de Calorimetria , Hidrólise , Espectroscopia de Infravermelho com Transformada de Fourier , Termogravimetria , Viscosidade , Difração de Raios X
13.
Int J Biol Macromol ; 62: 172-9, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23973495

RESUMO

This article is aimed to discuss the modification of guar gum through microwave irradiation by varying the time of irradiation. The characterization of the modified products was carried out using FTIR spectroscopic analysis. The FT-IR spectrum of the pure guar gum (GG) sample showed a broad peak at 3298 cm(-1) while the modified GG sample displayed a peak at 1541 cm(-1) which was absent in the crude sample. The X-ray diffraction (XRD) analysis confirmed the increase in crystallinity due to grafting of the sample with polyacrylamide (GG-g-PAM). Scanning electron microscope (SEM) images revealed that granular form of guar gum was changed into fibrillar structure after grafting. Thermo-gravimetric analysis of the modified samples was also carried out and discussed. The role of guar gum as a matrix for controlled release of drug triamcinolone was evaluated. The GG-acrylamide grafted samples presented a correlation between drug release and time of microwave exposure. The results revealed that such modified product has potential applications in colonic drug delivery system.


Assuntos
Resinas Acrílicas/química , Colo/metabolismo , Portadores de Fármacos/química , Galactanos/química , Mananas/química , Micro-Ondas , Gomas Vegetais/química , Polimerização , Portadores de Fármacos/farmacologia , Liberação Controlada de Fármacos , Hemólise/efeitos dos fármacos , Humanos , Triancinolona/química , Triancinolona/metabolismo
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