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1.
Genes (Basel) ; 14(9)2023 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-37761894

RESUMO

Paris polyphylla var. yunnanensis is a well-known medicinal plant that is mainly distributed in Southwest China; however, its genetic diversity and biodiversity processes are poorly understood. In this study, the sequences of cpDNA trnL-trnF fragments of 15 wild populations and 17 cultivated populations of P. polyphylla var. yunnanensis were amplified, sequenced, and aligned to study the population genetics of this species. Genetic diversity was analyzed based on nucleotide diversity, haplotype diversity, Watterson diversity, population-level diversity, and species-level genetic diversity. Genetic structure and genetic differentiation were explored using haplotype distribution maps and genetic distance matrices. A total of 15 haplotypes were identified in the 32 populations of P. polyphylla var. yunnanensis. Five unique haplotypes were identified from the fourteen haplotypes of the cultivated populations, while only one unique haplotype was identified from the ten haplotypes of the wild populations. The haplotype richness and genetic diversity of the cultivated populations were higher than those of the wild populations (HT = 0.900 vs. 0.861). In addition, there were no statistically significant correlations between geographic distance and genetic distance in the cultivated populations (r = 0.16, p > 0.05), whereas there was a significant correlation between geographical distance and genetic structure in the wild populations (r = 0.32, p > 0.05), indicating that there was a geographical and genetic connection between the wild populations. There was only 2.5% genetic variation between the wild populations and cultivated populations, indicating no obvious genetic differentiation between the wild and cultivated populations. Overall, the genetic background of the cultivated populations was complex, and it was hypothesized that the unique haplotypes and higher diversity of the cultivated populations were caused by the mixed provenance of the cultivated populations.


Assuntos
Ascomicetos , Besouros , Liliaceae , Animais , Biodiversidade , China , DNA de Cloroplastos/genética , Liliaceae/genética
2.
Int J Biol Macromol ; 242(Pt 3): 124895, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37196710

RESUMO

The remediation of heavy crude oil spills is a global challenge because frequent crude oil spills cause long-term damage to local living beings and marine ecosystems. Herein, a solar-driven and Joule-driven self-heated aerogel were developed as an all-weather adsorbent to efficiently absorb crude oil by obviously decreasing the viscosity of crude oil. The cellulose nanofiber (CNF)/MXene/luffa (CML) aerogel was fabricated via a simple freeze-drying method using CNF, MXene, and luffa as raw materials, and then coated with a layer of polydimethylsiloxane (PDMS) to make it hydrophobic and further increase oil-water selectivity. The aerogel can quickly reach 98 °C under 1 sun (1.0 kW/m2), which remains saturated temperature after 5 times photothermal heating/cooling cycles, indicating that the aerogel has great photothermal conversation capability and stability. Meanwhile, the aerogel can also rapidly rise to 110.8 °C with a voltage of 12 V. More importantly, the aerogel achieved the highest temperature of 87.2 °C under outdoor natural sunlight, providing a possibility for promising applications in practical situations. The remarkable heating capability enables the aerogel to decrease the viscosity of crude oil substantially and increase the absorption rate of crude oil by the physical capillary action. The proposed all-weather aerogel design provides a sustainable and promising solution for cleaning up crude oil spills.


Assuntos
Luffa , Nanofibras , Petróleo , Nanofibras/química , Celulose/química , Ecossistema , Tempo (Meteorologia)
3.
Int J Biol Macromol ; 223(Pt A): 1-10, 2022 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-36336151

RESUMO

Polymers with high conductivity and cross-linking ability are ideal materials for the preparation of conductive hydrogels for application in wearable electronic devices. However, the fabrication of conductive polymer-incorporated hydrogels with good synergistic properties remains a great challenge due to the hydrophobicity and opacity of conjugated π conductive polymers. In this study, a multifunctional hybrid hydrogel was prepared by incorporating hemicellulose-decorated polypyrrole (H/PPY), polyvinyl alcohol (PVA), and tannic acid (TA) into a polyacrylamide (PAM) network. The addition of excess ammonium persulfate (APS) in the process of gelation not only initiated the polymerization of PAM but also resulted in the change of the hydrogel from opaque to transparent by continuously breaking and reducing the size of the PPY particles. The hybrid hydrogel exhibited high transparency and conductivity, good adhesion ability and mechanical performance, and high resistance strain sensitivity and could accurately monitor the strain signals of the index finger and elbow flexion and pulse beat during rest and exercise, which has promising potential for use in wearable or implantable smart sensor devices, electronic skins, and artificial intelligence applications.


Assuntos
Hidrogéis , Polímeros , Humanos , Pirróis , Inteligência Artificial , Condutividade Elétrica , Aderências Teciduais
4.
Front Chem ; 10: 841956, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35211457

RESUMO

Tailoring the structure and properties of lignin is an important step toward electrochemical applications. In this study, lignin/polypyrrole (PPy) composite electrode films with microporous and mesoporous structures were designed effectively by electrostatic spinning, carbonization, and in situ polymerization methods. The lignin can not only reduce the cost of carbon fiber but also increase the specific surface area of composite films due to the removal of carbonyl and phenolic functional groups of lignin during carbonization. Besides, the compact three-dimensional (3D) conductive network structures were constructed with PPy particles densely coated on the lignin nanofibers, which was helpful to improve the conductivity and fast electron transfer during the charging and discharging processes. The synthesized lignin carbon fibers/PPy anode materials had good electrochemical performance in 1 M H2SO4 electrolyte. The results showed that, at a current density of 1 A g-1, the lignin carbon nanofibers/PPy (LCNFs/PPy) had a larger specific capacitance of 213.7 F g-1 than carbon nanofibers (CNFs), lignin carbon nanofibers (LCNFs), and lignin/PPy fiber (LPAN/PPy). In addition, the specific surface area of LCNFs/PPy reached 872.60 m2 g-1 and the average pore size decreased to 2.50 nm after being coated by PPy. Therefore, the independent non-binder and self-supporting conductive film is expected to be a promising electrode material for supercapacitors with high performance.

5.
J Colloid Interface Sci ; 606(Pt 2): 971-982, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34487944

RESUMO

Remediation of crude oil spills is a great challenge owing to the poor mobility and high viscosity of crude oil. Herein, a porous polydimethylsiloxane@wood sponge/MXene (PDMS@WSM) with outstanding compressibility and hydrophobic/lipophilic ability was demonstrated as crude oil absorbent. The surface temperature of PDMS@WSM could quickly rise to 80 °C with a working voltage of 4 V and to 66 °C under simulated sunlight irradiation of 1.5 KW m-2, respectively. Due to the excellent Joule heating and photothermal conversion effect, the PDMS@WSM displayed maximum adsorption capacity of 11.2×105 g m-3 within 6 min. The PDMS@WSM showed preferable reusability and cycle stability because of its brilliant compressibility. Moreover, the oil-collecting device based on PDMS@WSM could continuously collect crude oil spills, achieving an active collection of 25 mL crude oil within 150 s. Therefore, the porous PDMS@WSM absorbent exhibited great potential for crude oil spills remediation, energy regulation, and desalination of hypersaline water.


Assuntos
Poluição por Petróleo , Petróleo , Calefação , Poluição por Petróleo/análise , Titânio , Madeira
6.
Front Bioeng Biotechnol ; 9: 713860, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34368107

RESUMO

Paris polyphylla var. yunnanensis is a kind of biomass resource, which has important medicinal and economical values with a huge market. This review article aims to summarize the recent development of biomass P. polyphylla var. yunnanensis. The genetic diversity and chemical components of biomass P. polyphylla var. yunnanensis were reviewed based on the literature. Both the genetic diversity and genetic structure of biomass P. polyphylla var. yunnanensis were compared by using molecular marker technologies. All the extraction processes, harvest time, and drying methods on the chemical components were summarized in detail. The differences of arbuscular mycorrhizal fungi on the infection rate, diosgenin content, microorganisms, enzyme activities, rhizospheric environment, and endogenous hormones were discussed. This review article is beneficial for the applications of biomass P. polyphylla var. yunnanensis as a biomass resource in the biomedical field.

7.
Biotechnol Prog ; 34(2): 337-346, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29314787

RESUMO

The WRINKLED1 (WRI1) gene is a well-established key transcriptional regulator involved in the regulation of fatty acid biosynthesis in developing seeds. In this study, a new WRI1 gene was isolated from seeds of Eucommia ulmoides and named EuWRI1. A close link between gibberellins signaling and EuWRI1 gene expression was suggested in this study. Functional characterization of EuWRI1 was elucidated through seed-specific expression in tobacco. In transgenic tobacco, the expression of EuWRI1 in eight independent transgenic lines was detected by semiquantitative RT-PCR. The relative mRNA accumulation of genes encoding enzymes involved in fatty acid biosynthesis (biotin carboxyl carrier protein and keto-ACP synthase 1) was also assayed in tobacco seeds. Analysis of the seeds oil content and starch content indicated that the transgenic lines showed a significant increase in seeds oil content, whereas starch content decreased significantly. Further analysis of the fatty acid composition revealed that palmitic acid (16:0), linoleic acid (18:2) and linolenic acid (18:3) increased significantly in seeds of transgenic tobacco lines, but stearic acid (18:0) levels significantly declined. © 2018 American Institute of Chemical Engineers Biotechnol. Prog., 34:337-346, 2018.


Assuntos
Eucommiaceae/genética , Óleos de Plantas/metabolismo , Proteínas de Plantas/genética , Sementes/metabolismo , Fatores de Transcrição/genética , Expressão Ectópica do Gene , Ácidos Graxos/genética , Ácidos Graxos/metabolismo , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Giberelinas/metabolismo , Filogenia , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas , Regiões Promotoras Genéticas , Reação em Cadeia da Polimerase em Tempo Real , Sementes/genética , Sementes/crescimento & desenvolvimento , Fatores de Transcrição/metabolismo , Triazóis/farmacologia
8.
Curr Pharm Des ; 23(35): 5292-5300, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29086678

RESUMO

Cellulose is an important environmentally-friendly renewable polymer on the earth. Cellulose has been widely used as feedstocks for the synthesis of biomaterials, biofuels and biochemicals. Recently, cellulose and cellulose derivatives have received intense attention in biomedical applications, such as tissue engineering, scaffold, artificial blood vessel, skin grafts, artificial skin, drug carrier, and chronic skin diseases, many of which are somehow related to cancer therapy. In this mini-review, we focus on the up-to-date development of cellulosebased nanocarriers used for cancer therapy. Various cellulose-based nanocarriers such as bacterial cellulose (BC), cellulose acetate, microcrystalline cellulose, carboxymethyl cellulose, cellulose nanocrystals, cellulose nanofibrills, etc, are reviewed in terms of being used in drug delivery systems for cancer treatment. Different strategies for the synthesis of cellulose-based nanocarriers are summarized. Special attention is paid on the structure and properties of cellulose-based drug carriers for cancer therapy via some representative examples. Finally, the problems and future developments of these promising polymeric nanocarriers are raised and proposed.


Assuntos
Antineoplásicos/administração & dosagem , Celulose/administração & dosagem , Portadores de Fármacos/administração & dosagem , Nanopartículas/administração & dosagem , Neoplasias/tratamento farmacológico , Animais , Antineoplásicos/metabolismo , Celulose/metabolismo , Portadores de Fármacos/metabolismo , Humanos , Nanopartículas/metabolismo , Neoplasias/metabolismo
9.
Polymers (Basel) ; 8(9)2016 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-30974621

RESUMO

In this paper, we report a facile, rapid, and green strategy for the synthesis of cellulose/hydroxyapatite (HA) nanocomposites using an inorganic phosphorus source (sodium dihydrogen phosphate dihydrate (NaH2PO4·2H2O)), or organic phosphorus sources (adenosine 5'-triphosphate disodium salt (ATP), creatine phosphate disodium salt tetrahydrate (CP), or D-fructose 1,6-bisphosphate trisodium salt octahydrate (FBP)) through the microwave-assisted hydrothermal method. The effects of the phosphorus sources, heating time, and heating temperature on the phase, size, and morphology of the products were systematically investigated. The experimental results revealed that the phosphate sources played a critical role on the phase, size, and morphology of the minerals in the nanocomposites. For example, the pure HA was obtained by using NaH2PO4·2H2O as phosphorus source, while all the ATP, CP, and FBP led to the byproduct, calcite. The HA nanostructures with various morphologies (including nanorods, pseudo-cubic, pseudo-spherical, and nano-spherical particles) were obtained by varying the phosphorus sources or adjusting the reaction parameters. In addition, this strategy is surfactant-free, avoiding the post-treatment procedure and cost for the surfactant removal from the product. We believe that this work can be a guidance for the green synthesis of cellulose/HA nanocomposites in the future.

10.
ACS Macro Lett ; 4(8): 829-833, 2015 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-35596504

RESUMO

The biologically inspired dynamic materials offer principles for designing man-made systems by using assembly approach. In this work, the hybrid hydrogels consist of cellulose nanofibrils (CNFs) that combine a mechanically strong skeleton with flexible PEG chains. The distinct gel state is observed at room temperature with G' > G″ and an order of magnitude higher G' values from 0.08 to 0.93 kPa upon increasing CNF concentration from 0.2 to 2 wt % at constant 2 wt % PEG. Combined with mechanically strong CNFs and dynamic ionic bridges through amine-terminated tetra-arm PEG adsorption to TEMPO-oxidized colloidal nanofibrils surface, the assembled colloidal hydrogels show high modulus, reversible gel-sol transition, and rapid self-recovery properties. It is envisioned that simply mixing hard CNF and soft polymeric matrix would lead to a facile method to bridge reversible dynamic bonds in a cellulose-based hybrid network and broad cellulose applications in the preparation of high performance supramolecular systems.

11.
Carbohydr Polym ; 92(2): 1669-76, 2013 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-23399205

RESUMO

The purposes of this article are to synthesize the biomass-based hybrid nanocomposites using green method in green solvent and evaluate its biological activity. In this paper, microwave-assisted ionic liquid method is applied to the preparation of cellulose/CaCO(3) hybrid nanocomposites in the alkali extraction cellulose using CaCl(2) and Na(2)CO(3) as starting reactants. The ionic liquid acts as the excellent solvent for absorbing microwave and the dissolution of cellulose, and the synthesis of cellulose/CaCO(3) nanocomposites. The influences of reaction parameters such as the cellulose concentration and the types of solvent on the products were investigated. The increasing cellulose concentration favored the growth of CaCO(3). The morphologies of CaCO(3) changed from polyhedral to cube to particle with increasing cellulose concentration. Moreover, the solvents had an effect on the shape and dispersion of CaCO(3). Cytotoxicity experiments demonstrated that the cellulose/CaCO(3) nanocomposites had good biocompatibility and could be a candidate for the biomedical applications.


Assuntos
Materiais Biocompatíveis/química , Materiais Biocompatíveis/síntese química , Carbonato de Cálcio/química , Celulose/química , Líquidos Iônicos/química , Micro-Ondas , Nanocompostos/química , Materiais Biocompatíveis/toxicidade , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Técnicas de Química Sintética , Química Verde , Humanos , Nanocompostos/toxicidade , Solventes/química
12.
Ultrason Sonochem ; 20(3): 839-45, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23200085

RESUMO

The purposes of this article were to investigate the influences of synthesis strategy on the CaCO(3) crystals on the cellulose substrate. In this study, CaCO(3) crystals were synthesized using cellulose as matrix by the microwave-assisted method and ultrasound agitation method, respectively. The CaCO(3) crystals on the cellulose substrate were characterized by means of X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM). Experimental results demonstrated that the synthesis strategy had a dramatically influences on the phase, microstructure, morphology, thermal stability, and biological activity of the CaCO(3) crystals. The pure phase of vaterite spheres with the diameter of about 320-600nm were obtained by ultrasound agitation method, meanwhile, the mixed phases of calcite and vaterite with the diameter of about 0.82-1.24µm were observed by microwave-assisted method. In view of experimental results, one can conclude that the ultrasound agitation method do more favors to the synthesis of CaCO(3) crystals with uniform morphology and size, compared with microwave-assisted method. Furthermore, cytotoxicity experiments indicated that the CaCO(3) crystals on the cellulose substrate had good biocompatibility and could be a candidate for the biomedical applications.


Assuntos
Materiais Biocompatíveis/química , Carbonato de Cálcio/química , Celulose/química , Micro-Ondas , Sonicação/métodos , Materiais Biocompatíveis/toxicidade , Carbonato de Cálcio/toxicidade , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Celulose/toxicidade , Cristalização , Humanos , Teste de Materiais , Microscopia Eletrônica de Varredura , Tamanho da Partícula , Propriedades de Superfície , Difração de Raios X
13.
Mater Sci Eng C Mater Biol Appl ; 32(6): 1511-7, 2012 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-24364953

RESUMO

Nanocomposites of cellulose/iron oxide have been successfully prepared by hydrothermal method using cellulose solution and Fe(NO3)3·9H2O at 180 °C. The cellulose solution was obtained by the dissolution of microcrystalline cellulose in NaOH/urea aqueous solution, which is a good system to dissolve cellulose and favors the synthesis of iron oxide without needing any template or other reagents. The phases, microstructure, and morphologies of nanocomposites were characterized by X-ray powder diffraction (XRD), scanning electron microscopy (SEM), and energy-dispersive X-ray spectra (EDS). The effects of the heating time, heating temperature, cellulose concentration, and ferric nitrate concentration on the morphological behavior of products were investigated. The experimental results indicated that the cellulose concentration played an important role in both the phase and shape of iron oxide in nanocomposites. Moreover, the nanocomposites synthesized by using different cellulose concentrations displayed different thermal stabilities.


Assuntos
Celulose/química , Compostos Férricos/química , Nanocompostos/química , Microscopia Eletrônica de Varredura/métodos , Nitratos/química , Soluções/química , Temperatura , Difração de Raios X/métodos
14.
J Phys Chem B ; 110(29): 14226-30, 2006 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-16854124

RESUMO

Agglomerated nanorods of hydroxyapatite have been synthesized using monetite as a precursor in a NaOH solution. Monetite consisting of nanosheets has been successfully synthesized by a one-step microwave-assisted method using CaCl(2).2.5H(2)O, NaH(2)PO(4), and sodium dodecyl sulfate (SDS) in water/ethylene glycol (EG) mixed solvents. The effects of the molar ratio of water to EG and the reaction time on the products were investigated. The products were characterized by X-ray powder diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and Fourier transform infrared spectrometry (FTIR).


Assuntos
Fosfatos de Cálcio/síntese química , Durapatita/síntese química , Etilenoglicol/química , Nanotubos/química , Fosfatos de Cálcio/química , Durapatita/química , Durapatita/efeitos da radiação , Etilenoglicol/efeitos da radiação , Microscopia Eletrônica de Varredura , Micro-Ondas , Tamanho da Partícula , Difração de Pó , Solventes/química , Solventes/efeitos da radiação , Espectroscopia de Infravermelho com Transformada de Fourier , Água/química
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