RESUMO
The plant microbiome influence plant health, yield and vigor and has attained a considerable attention in the present era. In the current study, native bacterial community composition and diversity colonizing Triticum aestivum L. rhizosphere at two distant geographical locations including Mirpur Azad Kashmir and Islamabad was elucidated. Based on IonS5™XL platform sequencing of respective samples targeting 16S rRNA gene that harbor V3-V4 conserved region revealed 1364 and 1254 microbial operational taxonomic units (OTUs) at ≥97% similarity and were classified into 23, 20 phyla; 70, 65 classes; 101, 87 orders; 189,180 families; 275, 271 genera and 94, 95 species. Respective predominant phyla accounting for 97.90% and 98.60% of bacterial community were Proteobacteria, Actinobacteria, Acidobacteria, Bacteroidetes, Firmicutes, Chloroflexi and Gemmatimonadetes. Diversity indices revealed variations in relative abundance of bacterial taxa owing to distant geographical locations however predominant bacterial taxa at both locations were similar. These findings paved a way to dissect consequence of associated microbiota on future wheat production system.
Assuntos
Bactérias/classificação , Microbiota , Rizosfera , Microbiologia do Solo , Triticum/microbiologia , DNA Bacteriano/genética , Índia , Paquistão , RNA Ribossômico 16S/genéticaRESUMO
The Mn-based Mn2MoAl type ternary Heusler alloy is of particular interest due to its potential ferromagnetic properties and high spin-polarization. The present paper aims to explore the physical properties of this new alloy for its possible technological applications and also provide theoretical basis to the future experiments. The electronic structure, magnetism, and elastic properties of the alloy are studied by using first-principles calculations based on density functional theory (DFT), along with calculation of thermodynamic properties within quasi-harmonic approximation. The structural analysis predicts the optimized lattice constant of 5.90 Å and the ferromagnetic stable state. The electronic band structure calculations at GGA-level reveal that present alloy is nearly half-metal with spin-polarization up to 94% at the Fermi level, whereas, GGA + U calculations reveal Mn2MoAl alloy to be a quite spin polarized metal. The calculated total magnetic moment Mt of the unit-cell is found to be 1.04 µB, which nearly obeys Mt = âZt-24âformula. The individual Mn, Mo and Al atoms carry magnetic moment of 0.70 µB, -0.28 µB, -0.01µB, respectively. Employing quasi-harmonic approximation, interesting thermodynamic properties of the alloy have been investigated. Furthermore, the elastic and mechanical properties have been investigated. The results confirm that Mn2MoAl alloy is mechanically stable, ductile, anisotropic, with metallic inter-atomic bonding and is expected to be beneficial for the spintronic technology.
Assuntos
Ligas , Eletrônica , Imãs , Fenômenos Magnéticos , Magnetismo , TermodinâmicaRESUMO
Nanocomposite hydrogels have found a wide scope in regenerative medicine, tissue engineering, and smart drug delivery applications. The present study reports the formulations of biocompatible nanocomposite hydrogel films using carboxymethyl cellulose-hydroxyethyl cellulose-acrylonitrile-linseed oil polyol (CHAP) plain hydrogel and Na-montmorillonite (NaMMT) dispersed CHAP nanocomposite hydrogel films (NaCHAP) using solution blending technique. The structural, morphological, and mechanical properties of resultant nanocomposite hydrogel films were further investigated to analyze the effects of polyol and NaMMT on the characteristic properties. The synergistic effect of polyol and nanofillers on the mechanical strength and sustained drug-release behavior of the resultant hydrogel films was studied, which revealed that the increased cross-link density of hydrogels enhanced the elastic modulus (up to 99%) and improved the drug retention time (up to 72 h at both pHs 7.4 and 4.0). The release rate of cisplatin in nanocomposite hydrogel films was found to be higher in CHAP-1 (83 and 69%) and CHAP-3 (79 and 64%) than NaCHAP-3 (77 and 57%) and NaCHAP-4 (73 and 54%) at both pHs 4.0 and 7.4, respectively. These data confirmed that the release rate of cisplatin in nanocomposite hydrogel films was pH-responsive and increased with decrease of pH. All nanocomposite hydrogel films have exhibited excellent pH sensitivity under buffer solution of various pHs (1.0, 4.0, 7.4, and 9.0). The in vitro biocompatibility and cytotoxicity tests of these films were also conducted using 3-(4,5-dimethylthiazole-2-yl-2,5-diphenyl tetrazolium bromide) assay of human embryonic kidney (HEK-293) and human breast cancer (MCF-7) cell lines up to 48 h, which shows their biocompatible nature. However, cisplatin-loaded nanocomposite hydrogel films effectively inhibited the growth of human breast MCF-7 cancer cells. These studies suggested that the proposed nanocomposite hydrogel films have shown promising application in therapeutics, especially for anticancer-targeted drug delivery.
RESUMO
The synergistic contributions of nanofillers and polymer matrix induce remarkable properties in nanocomposite hydrogels. Present article reports the facile synthesis of biocompatible nanocomposite hydrogels using microporous multi wall carbon nanotubes (MWCNTs) dispersed chitosan (CH)-Acrylonitrile (AN), N,N'-methylenebisacrylamide (MBAAm) and linseed polyol through solution blending method. Polyol and N,N'-methylenebisacrylamide (MBAAm) was used as the crosslinking agent. The structural characterization and formation of highly crosslinked network with dendrimer morphology was confirmed by FT-IR and scanning electron microscope (SEM) analysis. In addition, transmission electron microscope (TEM) was employed to visualize the size and proper dispersion of MWCNT in the polymer matrices. The strong mechanical strength exhibited by these hydrogel films was confirmed by the tensile strength analysis. The dispersion of the conductive nanofillers, like MWCNTs has significantly enhanced the strength, which revealed unique characteristics of these hydrogel films. The high swelling capacity and sustained expansion of hydrogel films were confirmed in the buffer solutions of pH4 and 7.4. The biodegradability of these films was estimated by hydrolytic and soil burial tests. The biocompatibility test was conducted on Human Embryonic Kidney (HEK-293) cell line, which confirmed the non-toxic and biocompatible nature of these films. Incorporation of carbon nanotubes (MWCNTs) in the polymer matrix enhanced the film forming properties, high modulus and tensile strength, swelling ability, biodegradable and biocompatibility. These properties can be finely tuned through the variation of MWCNT concentrations, as a result these nanostructure hydrogel films have potential scope for their diverse applications in the field of tissue engineering.
Assuntos
Materiais Biocompatíveis/química , Hidrogéis/química , Nanocompostos/química , Engenharia Tecidual , Materiais Biocompatíveis/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Quitosana/química , Módulo de Elasticidade , Células HEK293 , Humanos , Hidrogéis/farmacologia , Interações Hidrofóbicas e Hidrofílicas , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Nanotubos de Carbono/química , Polímeros/química , Espectroscopia de Infravermelho com Transformada de Fourier , Resistência à Tração , Difração de Raios XRESUMO
The present study reports the formulations of biocompatible nanocomposite hydrogels using chitosan (CH), poly(vinyl alcohol) (PVA), oleo polyol, and fumed silica (SiO2) via a free radical polymerization method for anti-cancer drug delivery. Structural, morphological, and mechanical analyses were conducted using FT-IR spectroscopy, scanning electron microscopy, transmission electron microscopy, and rheological techniques. The effect of SiO2 concentration on mechanical strength, swelling ratios, morphological, and drug delivery behavior was investigated. The incorporation of SiO2 nanoparticles in hydrogels resulted in a significant enhancement in its properties. MTT assay of human embryonic kidney (HEK-293) and human colon (HCT116) cancer cell lines was conducted for up to 48 h to evaluate biocompatibility and cytotoxicity. These studies confirmed the biocompatible nature of nanocomposite hydrogels. Cisplatin-loaded nanocomposite hydrogels exhibit sustained release as compared to free cisplatin at pH 4.0 and pH 7.4. The in vitro cytotoxicity test of cisplatin-loaded hydrogels using the HCT116 cancer cell line indicates that these hydrogels successfully inhibit the growth of HCT116 cancer cells. The results of in vitro tests for drug loading, sustained release, biodegradability, biocompatibility, and anti-proliferative activity of cisplatin-loaded nanocomposite hydrogels suggest that, in the future, they may find applications in the development of topical (in vivo, in the form of tablets) drug delivery systems.