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1.
Ecotoxicol Environ Saf ; 268: 115732, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38000301

RESUMO

Glutathione plays a critical role in plant growth, development and response to stress. It is a major cellular antioxidant and is involved in the detoxification of xenobiotics in many organisms, including plants. However, the role of glutathione-dependent redox homeostasis and associated molecular mechanisms regulating the antioxidant system and pesticide metabolism remains unclear. In this study, endogenous glutathione levels were manipulated by pharmacological treatments with glutathione synthesis inhibitors and oxidized glutathione. The application of oxidized glutathione enriched the cellular oxidation state, reduced the activity and transcript levels of antioxidant enzymes, upregulated the expression level of nitric oxide and Ca2+ related genes and the content, and increased the residue of chlorothalonil in tomato leaves. Further experiments confirmed that glutathione-induced redox homeostasis is critical for the reduction of pesticide residues. RNA sequencing analysis revealed that miRNA156 and miRNA169 that target transcription factor SQUAMOSA-Promoter Binding Proteins (SBP) and NUCLEAR FACTOR Y (NFY) potentially participate in glutathione-mediated pesticide degradation in tomato plants. Our study provides important clues for further dissection of pesticide degradation mechanisms via miRNAs in plants.


Assuntos
Praguicidas , Solanum lycopersicum , Antioxidantes/metabolismo , Solanum lycopersicum/genética , Dissulfeto de Glutationa/metabolismo , Glutationa/metabolismo , Oxirredução , Praguicidas/metabolismo , Plantas/metabolismo , Homeostase , Estresse Oxidativo
2.
Physiol Plant ; 174(4): e13731, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35717632

RESUMO

Saline-alkali (SA) stress induces excessive reactive oxygen species (ROS) accumulation in plant cells, resulting in oxidative damages of membranes, lipids, proteins, and nucleic acids. Melatonin has antioxidant protection effects in living organisms and thus has received a lot of attention. This study aimed to investigate the effect and regulating mechanism of melatonin treatment on soybean tolerance to SA stress. In this study, cultivars Heihe 49 (HH49, SA-tolerant) and Henong 95 (HN95, SA-sensitive) were pot-cultured in SA soil, then treated with MT (0-300 µM) at V1 stage. SA stress induced ROS accumulation and DNA damage in the seedling roots of both cultivars, causing G1/S arrest in HN95 and G2/M arrest in HH49. Melatonin treatment enhanced the activity of antioxidant enzymes in soybean seedling roots and reduced ROS accumulation. Additionally, melatonin treatment upregulated DNA damage repair genes, thus enhancing the reduction of DNA oxidative damage under SA stress. The effects of melatonin treatment were manifested as decreased RAPD polymorphism, 8-hydroxy-2'-deoxyguanine (8-OH-dG) level, and relative density of apurinic sites (AP-sites). Meanwhile, melatonin treatment partially alleviated the SA-induced G1/S arrest in HN95 and G2/M arrest in HH49, thus enhancing soybean seedling tolerance to SA stress.


Assuntos
Fabaceae , Melatonina , Álcalis/metabolismo , Álcalis/farmacologia , Antioxidantes/metabolismo , Apoptose , Dano ao DNA , Fabaceae/genética , Pontos de Checagem da Fase G2 do Ciclo Celular , Melatonina/farmacologia , Estresse Oxidativo , Técnica de Amplificação ao Acaso de DNA Polimórfico , Espécies Reativas de Oxigênio/metabolismo , Estresse Salino , Plântula , Glycine max/metabolismo
3.
Ecotoxicol Environ Saf ; 233: 113296, 2022 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-35158253

RESUMO

Glutathione (GSH) biosynthesis and regeneration play a significant role in the metabolism of chlorothalonil (CHT) in tomatoes. However, the specific regulatory mechanism of GSH in the degradation of CHT remains uncertain. To address this, we investigate the critical regulatory pathways in the degradation of residual CHT in tomatoes. The results revealed that the detoxification of CHT residue in tomatoes was inhibited by buthionine sulfoximine and oxidized glutathione pretreatment, which increased by 26% and 46.12% compared with control, respectively. Gene silencing of γECS, GS, and GR also compromised the CHT detoxification potential of plants, which could be alleviated by GSH application and decreased the CHT accumulation by 33%, 25%, and 21%, respectively. Notably, it was found that the jasmonic acid (JA) pathway participated in the degradation of CHT regulated by GSH. CHT residues reduced by 28% after application of JA. JA played a role downstream of the glutathione pathway by promoting the degradation of CHT residue in tomatoes via nitric oxide signaling and improving the gene expression of antioxidant and detoxification-related enzymes. This study unveiled a crucial regulatory mechanism of GSH via the JA pathway in CHT degradation in tomatoes and offered new insights for understanding residual pesticide degradation.


Assuntos
Solanum lycopersicum , Ciclopentanos , Glutationa/metabolismo , Solanum lycopersicum/genética , Nitrilas , Oxilipinas/metabolismo
4.
Physiol Mol Biol Plants ; 28(6): 1261-1276, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35910446

RESUMO

Abiotic stress caused by unsuitable environmental changes brings serious impacts on the growth and development of sorghum, resulting in significant loss in yield and quality every year. Phospholipase D is one of the key enzymes that catalyze the hydrolysis of phospholipids, and participates in plants response to abiotic stresses and phytohormones, whereas as the main producers of Phosphatidic acid (PA) signal, the detailed information about Phospholipase D associated (SbPLD) family in sorghum has been rarely reported. This study was performed to identify the PLD family gene in sorghum based on the latest genome annotation and to determine the expression of PLDs under abiotic stresses by qRT-PCR analysis. In this study, 13 PLD genes were identified in sorghum genome and further divided into 7 groups according to the phylogenetic analysis. All sorghum PLD family members harbored two conserved domains (HDK1&2) with catalytic activity, and most members contained a C2 domain. In ζ subfamily, C2 domain was replaced by PX and PH domain. The exon-intron structure of SbPLD genes within the same subfamily was highly conservative. The tissue specific expression analysis revealed different expression of SbPLD genes in various developmental stages. High level expression of SbPLDα3 was observed in almost all tissues, whereas SbPLDα4 was mainly expressed in roots. Under abiotic stress conditions, SbPLD genes responded actively to NaCl, ABA, drought (PEG) and cold (4 °C) treatment at the transcriptional level. The expression of SbPLDß1 was significantly up-regulated, while the transcription of SbPLDζ was suppressed under various stress conditions. In addition, SbPLDß1 and SbPLDδ2 were predicted to be the target genes of sbi-miR159 and sbi-miR167, respectively. This study will help to decipher the roles of PLDs in sorghum growth and abiotic stress responses. Supplementary Information: The online version contains supplementary material available at 10.1007/s12298-022-01200-9.

5.
J Environ Sci (China) ; 113: 55-63, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34963549

RESUMO

Soil aggregation plays an important role in agricultural production activities. However, the structure of soil aggregation is destroyed by the natural environment and unreasonable farming management, resulting in the loss of water, fertilizers and pesticides in soil. At present, hydrogels have been widely reported to promote the formation of soil aggregation. In this paper, amphiphilic calcium alginate (ASA/Ca2+) was applied to promote the formation of soil aggregation and enhance pesticide retention. Initially, an ASA was obtained through the one-pot Ugi condensation (a four-component green chemical reaction). Then, ASA/Ca2+ hydrogel is prepared by Ca2+ cross-linking. The formation of soil aggregation was determined through the Turbiscan Lab Expert stability analyzer, Confocal Laser Scanning Microscope (CLSM), and Transmission Electron Microscope (TEM). And the effect of soil aggregation on acetamiprid environmental behavior was investigated by adsorption kinetics, adsorption isotherms, and leaching. The results shown that the three-dimensional network structure of ASA/Ca2+ hydrogel can promote the formation of soil aggregation. Aggregate durability index (ADI) was 0.55 in the presence of ASA/Ca2+ hydrogel, indicating that amphiphilic hydrogel can enhance the stability of soil aggregation. The adsorbing capacity of acetamiprid was 1.58 times higher than pure soil, and the release of acetamiprid only about 20% in the presence of ASA/Ca2+ hydrogel. These results would be helpful for the formation of soil aggregation and pesticides adsorption on soil aggregation. Thus, ASA/Ca2+ hydrogel is likely to improve soil quality, simultaneously it can minimize the mobility of pesticides in the agricultural system.


Assuntos
Alginatos , Solo , Adsorção , Hidrogéis , Neonicotinoides , Polissacarídeos
6.
New Phytol ; 228(5): 1573-1590, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32619295

RESUMO

CDK8 is a key subunit of Mediator complex, a large multiprotein complex that is a fundamental part of the conserved eukaryotic transcriptional machinery. However, the biological functions of CDK8 in plant abiotic stress responses remain largely unexplored. Here, we demonstrated CDK8 as a critical regulator in the abscisic acid (ABA) signaling and drought response pathways in Arabidopsis. Compared to wild-type, cdk8 mutants showed reduced sensitivity to ABA, impaired stomatal apertures and hypersensitivity to drought stress. Transcriptomic and chromatin immunoprecipitation analysis revealed that CDK8 positively regulates the transcription of several ABA-responsive genes, probably through promoting the recruitment of RNA polymerase II to their promoters. We discovered that both CDK8 and SnRK2.6 interact physically with an ERF/AP2 transcription factor RAP2.6, which can directly bind to the promoters of RD29A and COLD-REGULATED 15A (COR15A) with GCC or DRE elements, thereby promoting their expression. Importantly, we also showed that CDK8 is essential for the ABA-induced expression of RAP2.6 and RAP2.6-mediated upregulation of ABA-responsive genes, indicating that CDK8 could link the SnRK2.6-mediated ABA signaling to RNA polymerase II to promote immediate transcriptional response to ABA and drought signals. Overall, our data provide new insights into the roles of CDK8 in modulating ABA signaling and drought responses.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Quinase 8 Dependente de Ciclina , Fatores de Transcrição , Ácido Abscísico , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Quinase 8 Dependente de Ciclina/genética , Secas , Regulação da Expressão Gênica de Plantas , Proteínas Serina-Treonina Quinases/metabolismo , Estresse Fisiológico/genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
7.
J Environ Sci (China) ; 78: 230-238, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30665641

RESUMO

The effects of amphiphilic O/W emulsions, stabilized by the alkyl polyglycoside (APG) or cholesterol-grafted sodium alginate (CSAD)/APG systems, on lambda-cyhalothrin adsorption/desorption mechanisms on natural soil minerals (i.e., illite and kaolinite) were investigated. Sorption and desorption of lambda-cyhalothrin onto soil minerals was studied via batch equilibration to give insight into the adsorption equilibrium, kinetics, and thermodynamics of lambda-cyhalothrin adsorption onto minerals. The results indicate the following: (i) The adsorption processes for the APG system and CSAD/APG system include: rapid adsorption, slow adsorption, and adsorption equilibrium. The adsorption kinetics of pesticide on illite and kaolinite are in accordance with the Ho and McKay model, and the adsorption isotherm conforms to the Freundlich model. In addition, the adsorption processes of pesticide for the two systems on minerals were spontaneous and feasible (ΔG0 < 0), endothermic (ΔH0 > 0), and mainly involved chemical bonding (ΔH0 > 60). (ii) The equilibrium adsorption percentages of the pesticide on illite for the APG system and CSAD/APG system were 42.4% and 64.8%, and the corresponding equilibrium adsorption percentages on kaolinite were 40.8% and 61.8%, respectively. Moreover, the pesticide adsorption rate K2-CSAD/APG was faster than K2-APG, and its adsorption capacity Kf-CSAD/APG was greater than Kf-APG. Meanwhile, the pesticide desorption Kfd in the CSAD/APG system was smaller than that in the APG system. As a result, this eco-friendly O/W emulsion based on amphiphilic sodium alginate derivatives might provide a green pesticide formulation, since it could reduce the amount of lambda-cyhalothrin entering aquatic systems to threaten non-target fish and invertebrate species.


Assuntos
Alginatos/química , Recuperação e Remediação Ambiental/métodos , Minerais/química , Nitrilas/química , Piretrinas/química , Poluentes do Solo/química , Adsorção , Emulsões , Química Verde , Caulim , Cinética , Modelos Químicos , Praguicidas/análise , Praguicidas/química , Solo , Poluentes do Solo/análise
8.
Phys Chem Chem Phys ; 18(34): 23500-7, 2016 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-27465065

RESUMO

In nanobiotechnology applications, curvature of nanoparticles has a significant effect on protein activities. In this work, lysozyme adsorption on different-sized silica nanoparticles (SNPs) was simulated at the microsecond timescale by using mesoscopic coarse-grained molecular dynamics simulations. It is found that, with the increase of nanoparticle size, which indicates a decrease of surface curvature, adsorbed lysozyme shows a narrower orientation distribution and a greater conformation change, as the electrostatic attraction dominates lysozyme adsorption, and this trend is more pronounced on larger SNPs. Interestingly, the effect induced by different SNP surface curvatures is not related to the direct contact area between lysozyme and SNPs, but to the interfacial hydration layer above the silica surface, since a smaller curvature can lead to a stronger interfacial hydration and make the distribution of interfacial water molecules more ordered. Besides, at higher ionic strength, lysozyme conformation is less affected by strongly negatively charged SNPs, especially for larger nanoparticles. This work might shed some light on how to prepare protein coronas with higher bioactivities in nanobiotechnology.

9.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(5): 1389-95, 2016 May.
Artigo em Zh | MEDLINE | ID: mdl-30001012

RESUMO

The UV-B radiation on the surface of our planet has been enhanced due to gradual thinning of ozone layer. The change of solar spectrum UV-B radiation will cause damage to all kinds of terrestrial plants at certain degree. In this paper, taking breeding sorghum (Sorghum bicolor (L.Moench))variety Longza No.5 as sample, 40 µW·cm-2 UV-B radiation treatment was conducted on sorghum seedlings at two-leaf and one-heart stage and different time courses; then after a 2 d recovering, photosynthetic parameters were measured with a photosynthetic apparatus; the activities of antioxidant enzymes were detected as well. Our results revealed that, as the dosages of UV-B increasing, leaf browning injury was aggravated, plants dwarfing and significantly were reduced fresh weight and dry weight were observed; anthocyanin content was significantly increased; chlorophyll and carotenoid content significantly were reduced and net photosynthetic rate and chlorophyll fluorescence parameters were decreased. Meanwhile, with the increase in UV-B dosages, stomatal conductance, intercellular CO2 concentration and transpiration rate showed "down - up - down" trend; the activities of SOD and GR presented "down - up" changes; activities of POD and CAT demonstrated "down - up - down", and APX, GPX showed an "up - down - up" pattern. It is worth to note that, under the four-dose treatment, a sharp decline in net photosynthesis in sorghum seedlings was observed at 6 h UV-B treatment (equals to 2.4 J·m-2), and an obvious turning point was also found for other photosynthetic parameters and activities of antioxidant enzymes at the same time point. In summary, the results indicated that the enhanced UV-B radiation directly accounted for the damages in photosynthesis system including photosynthetic pigment content, net photosynthetic rate and chlorophyll fluorescence parameters of sorghum; the antioxidant system showed different responses to UV-B radiation below or above 6 h treatment: ASA-GSH cycle was more sensitive to low-dose UV-B radiation, while high-dose UV-B radiation not only undermined the photosynthesis system, but also triggered plant enzymatic and non-enzymatic antioxidant systems, resulting in leaf browning and necrosis,biomass accumulation reduction, plant dwarfing and even death.


Assuntos
Sorghum , Antioxidantes , Biomassa , Clorofila , Fotossíntese , Folhas de Planta , Plântula , Raios Ultravioleta
10.
Langmuir ; 31(39): 10751-63, 2015 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-26379082

RESUMO

The surrounding conditions, such as surface charge density and ionic strength, play an important role in enzyme adsorption. The adsorption of a nonmodular type-A feruloyl esterase from Aspergillus niger (AnFaeA) on charged surfaces was investigated by parallel tempering Monte Carlo (PTMC) and all-atom molecular dynamics (AAMD) simulations at different surface charge densities (±0.05 and ±0.16 C·m(-2)) and ionic strengths (0.007 and 0.154 M). The adsorption energy, orientation, and conformational changes were analyzed. Simulation results show that whether AnFaeA can adsorb onto a charged surface is mainly controlled by electrostatic interactions between AnFaeA and the charged surface. The electrostatic interactions between AnFaeA and charged surfaces are weakened when the ionic strength increases. The positively charged surface at low surface charge density and high ionic strength conditions can maximize the utilization of the immobilized AnFaeA. The counterion layer plays a key role in the adsorption of AnFaeA on the negatively charged COOH-SAM. The native conformation of AnFaeA is well preserved under all of these conditions. The results of this work can be used for the controlled immobilization of AnFaeA.

11.
Int J Biol Macromol ; 267(Pt 2): 131588, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38615860

RESUMO

Dietary selenium (Se) supplementation has recently received increasing attention; however, Selenium nanoparticles (SeNPs) exhibit poor stability and tend to aggregate in aqueous solution. Therefore, enhancing the stability of SeNPs and their effective delivery to plants remain challenging. In this study, sodium alginate (SA) and lysozyme (LZ) were reacted via the wet-heat Maillard reaction (MR) to obtain amphiphilic alginate-based polymers (SA-LZ). Alkyl glycosides (APG) were introduced into SA-LZ to enhance the deposition of SeNPs in leaves. Thus, a renewable and degradable polysaccharide-based material (SA-LZ/APG) loaded with Se formed an amphiphilic alginate-based-based shell with a Se core. Notably, the encapsulation of SeNPs into a polysaccharide base (SA-LZ/APG) increased the stabilization of SeNPs and resulted in orange-red, zero-valent, monoclinic and spherical SeNPs with a mean diameter of approximately 43.0 nm. In addition, SA-LZ/APG-SeNPs reduced the interfacial tension of plant leaves and increased the Se content of plants compared to the blank group. In vitro studies have reported that SA-LZ/APG-SeNPs and SA-LZ-SeNPs have significantly better clearance of DDPH and ABTS than that of APG-SeNPs. Thus, we believe that SA-LZ/APG is a promising smart delivery system that can synergistically enhance the stability of SeNPs in aqueous solutions and improve the bioavailability of Se nutrient solutions.


Assuntos
Alginatos , Glicosídeos , Nanopartículas , Selênio , Alginatos/química , Selênio/química , Nanopartículas/química , Glicosídeos/química , Folhas de Planta/química , Muramidase/química , Tensoativos/química , Estabilidade de Medicamentos
12.
Carbohydr Polym ; 334: 121892, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38553196

RESUMO

High quantum yield polysaccharide-based materials are significative for the dynamic anti-counterfeiting, while that are limited by weak fluorescence. However, natural polysaccharides with weak fluorescence are not suitable for anti-counterfeiting. Herein, alginate derivatives (SA-PBA) exhibiting aggregation-induced emission with high-quantum yields were synthesized by grafting phenylboronic acid (PBA) onto a sodium alginate (SA) chain. As the concentration increases, polymer assembly can be induced to form more compact soft colloidal aggregates, which enhances the fluorescence properties of alginate derivatives by introducing B â† N coordination bonds in the hydrophobic microregions. Interestingly, the clustered aggregates of SA-PBA can be dynamically controlled by pH, realizing the reversible adjustment of fluorescence. The corresponding mechanism is revealed by the combination of coarse-grained simulations and experiments. It is found that SA-PBA uses a hydrophobic driving force and hydrogen bond interaction to self-assemble in an aqueous solution and promote fluorescence emission. Moreover, the fluorescence quantum yield of SA-PBA can reach 14.4 % and can be reversibly altered by tuning soft colloidal microstructures. Therefore, a reversible information encryption system of SA-PBA is developed for anti-counterfeiting. This work shed some light on how to design novel anti-counterfeit materials based on natural polysaccharides and optimize the dynamic fluorescence conditions.

13.
Biointerphases ; 18(3)2023 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-37195015

RESUMO

Protein coronas, formed by proteins and nanomaterials, have various applications in the biomedical field. Here, large-scale simulations of protein coronas have been carried out by an efficient mesoscopic coarse-grained method with the BMW-MARTINI force field. The effects of protein concentration, size of silica nanoparticles (SNPs), and ionic strength on the formation of lysozyme-SNP coronas are investigated at the microsecond time scale. Simulations results indicate that (i) an increase in the amount of lysozyme is favorable for the conformation stability of adsorbed lysozyme on SNPs. Moreover, the formation of ringlike and dumbbell-like aggregations of lysozyme can further reduce the conformational loss of lysozyme; (ii) for a smaller SNP, the increase of protein concentration exhibits a greater effect on the adsorption orientation of lysozyme. The dumbbell-like lysozyme aggregation is unfavorable for the stability of lysozyme's adsorption orientation; however, the ringlike lysozyme aggregation can enhance the orientation stability; (iii) the increase of ionic strength can reduce the conformation change of lysozyme and accelerate the aggregation of lysozyme during their adsorption process on SNPs. This work provides some insights into the formation of protein coronas and some valuable guidelines for the development of novel biomolecule-NP conjugates.


Assuntos
Nanopartículas , Nanoestruturas , Muramidase/metabolismo , Dióxido de Silício , Adsorção
14.
Int J Biol Macromol ; 231: 123233, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36642363

RESUMO

Hydrophobically modified sodium alginate stabilizes benzene in water emulsions. The stability of the emulsion is related to the interface properties at the mesoscopic scale, but the details of the polymer adsorption, conformation and organization at oil/water interfaces at the microscopic scale remain largely elusive. In this study, hydrophobically modified sodium alginate was used as a representative of amphiphilic polymers for prediction of distribution of HMSA at the oil/water interface by coarse-grained molecular dynamics simulation. The result showed that driven by the interaction energy between the hydrophobic segment and benzene, HMSA will actively accumulate at the oil/water interface. The HMSA molecules parallel to the oil/water interface prevent the hydrophobic segments in the micelles from approaching the oil/water interface, so that the micelles can exist stably by steric hindrance. This study would be helpful to understand the aggregation behavior of amphiphilic polymers at the oil/water interface, these results can have applications in diverse sectors such as drug, food industry, where polymers are used to stabilize emulsions.


Assuntos
Micelas , Simulação de Dinâmica Molecular , Emulsões/química , Benzeno , Polímeros/química
15.
Carbohydr Polym ; 299: 120170, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36876785

RESUMO

Functional Pickering emulsions that depend on the interparticle interactions hold promise for building template materials. A novel coumarin-grafting alginate-based amphiphilic telechelic macromolecules (ATMs) undergoing photo-dimerization enhanced particle-particle interactions and changed the self-assembly behavior in solutions. The influence of self-organization of polymeric particles on the droplet size, microtopography, interfacial adsorption and viscoelasticity of Pickering emulsions were further determined by multi-scale methodology. Results showed that stronger attractive interparticle interactions of ATMs (post-UV) endowed Pickering emulsion with small droplet size (16.8 µm), low interfacial tension (9.31 mN/m), thick interfacial film, high interfacial viscoelasticity and adsorption mass, and well stability. The high yield stress, outstanding extrudability (n1 < 1), high structure maintainability, and well shape retention ability, makes them ideal inks for direct 3D printing without any additions. The ATMs provides an increased capacity to produce stable Pickering emulsions with tailoring their interfacial performances and, providing a platform for fabricating and developing alginate-based Pickering emulsion-templated materials.

16.
Int J Biol Macromol ; 224: 1244-1251, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36306916

RESUMO

The controlled release of nitric oxide (NO) is significantly crucial in the NO-related biomedical field. In the current work, the controlled release of NO from alginate microspheres was achieved through the direct impregnation of S-nitroso-N-acetyl-penicillamine (SNAP) in the gelation of sodium alginate with calcium ions. The loading rate of SNAP in alginate microspheres was obtained in a range of 0.69 %­27.5 %. Specifically, the longest NO release time reached up to ∼93 h. Furthermore, the structure, thermal properties, and morphology were fully characterized. During the antibacterial studies, the NO-releasing spheres can produce a great bactericidal effect on Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus). The alginate microspheres impregnated with 315 mg SNAP (sphere size: 2.88 mm) can effectively reduce the number of bacteria by 7 orders of magnitude with an inhibition rate up to 100 %. Therefore, we anticipated that these NO-releasing alginate microspheres would have great potential for biomedical-related applications.


Assuntos
Alginatos , Óxido Nítrico , Óxido Nítrico/química , Preparações de Ação Retardada/química , Alginatos/química , Microesferas , Staphylococcus aureus , Escherichia coli , S-Nitroso-N-Acetilpenicilamina/química , S-Nitroso-N-Acetilpenicilamina/farmacologia , Antibacterianos/farmacologia
17.
ACS Appl Mater Interfaces ; 15(19): 23989-24002, 2023 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-37134135

RESUMO

Significant challenges remain in designing sufficient viscoelasticity polysaccharide-based high internal phase Pickering emulsions (HIPPEs) as soft materials for 3D printing. Herein, taking advantage of the interfacial covalent bond interaction between modified alginate (Ugi-OA) dissolved in the aqueous phase and aminated silica nanoparticles (ASNs) dispersed in oil, HIPPEs with printability were obtained. Using multitechniques coupling a conventional rheometer with a quartz crystal microbalance with dissipation monitoring, the correlation between interfacial recognition coassembly on the molecular scale and the stability of whole bulk HIPPEs on the macroscopic scale can be clarified. The results showed that Ugi-OA/ASNs assemblies (NPSs) were strongly retargeted into the oil-water interface due to the specific Schiff base-binding between ASNs and Ugi-OA, further forming thicker and more rigid interfacial films on the microscopic scale compared with that of the Ugi-OA/SNs (bared silica nanoparticles) system. Meanwhile, flexible polysaccharides also formed a 3D network that suppressed the motion of the droplets and particles in the continuous phase, endowing the emulsion with appropriately viscoelasticity to manufacture a sophisticated "snowflake" architecture. In addition, this study opens a novel pathway for the construction of structured all-liquid systems by introducing an interfacial covalent recognition-mediated coassembly strategy, showing promising applications.

18.
J Colloid Interface Sci ; 645: 580-590, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37167908

RESUMO

The soft interfacial template-assisted confined self-assembly of block copolymers (BCPs) guiding colloidal aggregates has been extensively investigated by interfacial instability. Whether the macromolecular polymer architectonics possessed stimulus-responsive self-regulated structural controllability more readily implement the morphological diversity of colloidal aggregates. Herein, we in-situ constructed the alginate-modified ß-cyclodextrin/azobenzene-functionalized alkyl chains (Alg-ß-CD/AzoC12) system by supramolecular host-guest interfacial recognition-engineered strategy, in which possessed photo-stimulated responsive structural reconfigurability by modulating assembly/disassembly behaviors between CD and Azo at oil/water interface. The host-guest droplet interfaces acted as soft templates managing interfacial instability by synergistically integrating supra-amphiphilic host-guest polymers with cosurfactants, further constructing various soft supracolloidal aggregates, including soft nanoaggregates, microspheres with tunable degrees of surface roughness. Additionally, the stimuli-altering structural reconfigurability of supramolecular host-guest polymers was regulated by ultraviolet/visible irradiation, endowing soft aggregates with structural diversity. It's highly anticipated that the supramolecular host-guest interfacial recognition self-assembly establishes great bridge between supramolecular host-guest chemistry and colloid interface science.

19.
Carbohydr Polym ; 310: 120720, 2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-36925246

RESUMO

Polysaccharide-based soft colloidal particles mediated by the dynamic bonding-engineered interfacial self-assembly can regulate the properties of oil-water interfacial films, availing the stability of emulsions under a wide pH range. The amphiphilic phenylboronic alginate soft colloidal particles (Alg-PBA) were designed to stabilize pH-responsive Pickering emulsions (PEs). Combining stability analysis with quartz crystal microbalance and dissipation monitoring (QCM-D), the microstructure and viscoelasticity of Alg-PBA at the oil-water interface were determined. The results showed that PEs stabilized by Alg-PBA due to a thicker and stronger viscoelastic interface film induced by BO bonds and hydrogen bonds. The structure-function relationship of the Alg-PBA emulsifier driven by dynamic bonds was further elaborated at multiple scales by laser scanning microscopy (CLSM) and scanning electron microscopy (SEM). Meanwhile, the microstructure of aerogels templated by emulsion could be tuned by adjusting dynamic bonds, which provides a new idea for polysaccharide soft material engineering.

20.
Front Plant Sci ; 14: 1097001, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36875623

RESUMO

Groundnut or peanut (Arachis hypogaea) is a legume crop. Its seeds are rich in protein and oil. Aldehyde dehydrogenase (ALDH, EC: 1.2.1.3) is an important enzyme involved in detoxification of aldehyde and cellular reactive oxygen species, as well as in attenuation of lipid peroxidation-meditated cellular toxicity under stress conditions. However, few studies have been identified and analyzed about ALDH members in Arachis hypogaea. In the present study, 71 members of the ALDH superfamily (AhALDH) were identified using the reference genome obtained from the Phytozome database. A systematic analysis of the evolutionary relationship, motif, gene structure, cis-acting elements, collinearity, Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment, and expression patterns was conducted to understand the structure and function of AhALDHs. AhALDHs exhibited tissue-specific expression, and quantitative real-time PCR identified significant differences in the expression levels of AhALDH members under saline-alkali stress. The results revealed that some AhALDHs members could be involved in response to abiotic stress. Our findings on AhALDHs provide insights for further study.

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