The effects to elicit resistance reaction on oilseed rape (Brassica napus L. cv Xinongchangjiao ) by four partially N-acetylated chitosan 7B, 8B, 9B and 10B (Degree of acetylation (D. A.) is 30% , 20% , 10%, 0%, respe...The effects to elicit resistance reaction on oilseed rape (Brassica napus L. cv Xinongchangjiao ) by four partially N-acetylated chitosan 7B, 8B, 9B and 10B (Degree of acetylation (D. A.) is 30% , 20% , 10%, 0%, respectively) and Glycol chitosan (GC, D.A. is 0%) were investigated and compared. Results showed that chitosan were similar to salicylic acid (SA), and could induce resistance reaction, but the reaction was influenced by the degree of acetylation of chitosan. Fully deacetylated chitosans, 10B and GC, elicited chitinase activity, but partially acetylated chitosan, 7B, 8B and 9B, inhibited chitinase activity. Phenyalanine ammonia-lyase (PAL) was also elicited. Elicitor activity increased with on increasing degree of acetylation, 7B induced highest PAL activity among all chitosans. All chitosans induced peroxidase (POD) in a similar level. After elicited by glycol chitosan, like SA treatment, the seedlings increased disease resistance to Sclerotinia sclerotiorum significantly.展开更多
Original chitosan with M-v of 2.7 x 10(5) was degraded by irradiation with gamma-rays and a series of low molecular weight O-carboxymethylated chitosans (O-CMCh) were prepared based on the irradiated chitosan. A kinet...Original chitosan with M-v of 2.7 x 10(5) was degraded by irradiation with gamma-rays and a series of low molecular weight O-carboxymethylated chitosans (O-CMCh) were prepared based on the irradiated chitosan. A kinetic model of the irradiation of chitosan was put forward. Results show that the irradiation degradation of chitosan obeys the rule of random degradation and the degree of deacetylation of irradiated chitosan is slightly raised. The antibacterial activity of O-CMCh is significantly influenced by its MW, and a suppositional antibacterial peak appears when M-v is equal to 2 x 10(5).展开更多
The purpose of this research is to investigate the effects of the variously sulfated chitosans on lysozyme activity and structure. It was shown that the specific enzymatic activity of lysozyme remained almost similar ...The purpose of this research is to investigate the effects of the variously sulfated chitosans on lysozyme activity and structure. It was shown that the specific enzymatic activity of lysozyme remained almost similar to the native protein after being bound to 6-O-sulfated chitosan （6S-chitosan） and 3,6-O-sulfated chitosan （3,6S-chitosan）, but decreased greatly after being bound to 2-N-6-O-sulfated chitosan （2,6S-chitosan）. Meanwhile, among these sulfated chitosans, 2,6S-chitosan induced the greatest conformational change in lysozyme as indicated by the fluorescence spectra. These findings demonstrated that when sulfated chitosans of different structures bind to lysozyme, lysozyme undergoes conformational change of different magnitudes, which results in corresponding levels of lysozyme activity. Further study on the interaction of sulfated chitosans with lysozyme by surface plasmon resonance （SPR） suggested that their affinities might be determined by their molecular structures.展开更多
Five kinds of carboxymethyl sulfochitosans with different regions such as N-carboxymethyl-O-sulfochitosan, O-carboxymethyl-N-sulfochitosan, O-carboxymethyl chitosan sulfate, N-carboxymethyl chitosan-6-sulfate, and N,O...Five kinds of carboxymethyl sulfochitosans with different regions such as N-carboxymethyl-O-sulfochitosan, O-carboxymethyl-N-sulfochitosan, O-carboxymethyl chitosan sulfate, N-carboxymethyl chitosan-6-sulfate, and N,O-carboxymethyl -N,O-sulfochitosan were prepared respectively by using differential carboxymethylation and sulfation methods, and their IR spectrum and 13C-NMR spectrum were measured.展开更多
Chitosan is a biopolymer obtained from chitin, where the N-acetylglucosamine monomer is in its deacetylated form; this polymer is useful for a wide variety of industrial applications. The properties and uses of chitos...Chitosan is a biopolymer obtained from chitin, where the N-acetylglucosamine monomer is in its deacetylated form; this polymer is useful for a wide variety of industrial applications. The properties and uses of chitosan depend on its physical and chemical characteristics, which result from the treatments used for its production. In this study, we report the preparation and characterization ofchitosan oligosaccharides by a green synthesis from crystalline shrimp chitin, using a sequential enzyme treatment by chitinase and chitin deacetylase. Chitinases were purified from grapes and used to rupture the crystalline shrimp chitin structure, modifying the crystallinity index from 57.6% to 15.9%. The resultant polymers were deacetylated using a recombinant chitin deacetylase from Saccharomyces cerevisiae, which was cloned and expressed in Pichia pastoris. The chitosans produced showed an estimated DA （degree of acetylation） of approximately 20%, and the molecular weights ranged from -7,600 to -3,700 after treatment in pH 3.0 and pH 6.0 for 10 min and 40 min, respectively. Physical and chemical characterization of the products indicated that enzyme fragmentation of chitin probably makes the acetamide groups more accessible to deacetylation, forming homogeneous polymers that are free of hazardous sub-products, have defined low molecular weights, and are highly deacetylated.展开更多
The potent antibacterial activity of silver nanoparticles is primarily attributed to the release of silver ions,which disrupt cell membranes and inactivate essential enzymes through Ag−S bonding formation.[Objective]T...The potent antibacterial activity of silver nanoparticles is primarily attributed to the release of silver ions,which disrupt cell membranes and inactivate essential enzymes through Ag−S bonding formation.[Objective]To explore silver ion immobilization to minimize silver release.[Methods]A macrocyclic cryptand with nitrogen bridgeheads was prepared and subsequently chelated with silver ions to produce Cage silver(I),which was then coordinated with different ratios of sulfonated chitosan(SCS)to form SCS/Cage Ag(I)complexes(SCA1,SCA2,and SCA3).The antioxidant activities of the complexes were assessed by reducing power and 1,1-diphenyl-2-picrylhydrazyl(DPPH)free radical and hydrogen peroxide scavenging assays.The antibacterial activities of the complexes were evaluated based on the minimum inhibitory concentrations(MICs)and minimum bactericidal concentrations(MBCs)against Staphylococcus aureus ATCC 6538 and Escherichia coli O157:H7 and the inhibition rate on biofilm formation.[Results]Cage silver(I)exhibited strong antibacterial activity,with the MIC of 0.015 mg/mL and MBC of 0.031 mg/mL against S.aureus ATCC 6538,and the MIC of 0.031 mg/mL and MBC of 0.120 mg/mL against E.coli O157:H7.Significant antioxidant properties of Cage silver(I)were also observed,as demonstrated by the DPPH free radical scavenging rates of 42.2%and 53.1%at 326 nm and 517 nm,respectively.Cage silver(I)exhibited the highest antibacterial and antioxidant activities,followed by SCA1,SCA2,SCA3,and SCS,because the content of silver ions in Cage silver(I)was 10-fold higher than that in SCA1.The antibacterial and antioxidant activities of SCA1 were better than those of Cage silver(I),which further indicated that the sulfonic groups of SCS may intensely coordinate with silver ions to exert synergistic effects.[Conclusion]Combining the merits of silver ions and SCS improves the bioavailability of the agent at microbicidal concentrations,minimizes the accumulation in the environment,and reduces treatment costs.The method developed herein offers a sustainable approach to enhance microbial control while minimizing the impact on the environment.展开更多
The combination of solar disinfection and photocatalysis technology presents a viable solution for eliminating harmful pathogenic microorganisms from water.However,some photocatalysts(e.g.,zinc oxide-based composites)...The combination of solar disinfection and photocatalysis technology presents a viable solution for eliminating harmful pathogenic microorganisms from water.However,some photocatalysts(e.g.,zinc oxide-based composites)are susceptible to pH-dependent dissolution in water,which can result in the loss of photocatalysts and additional environ-mental pollution.To obtain zinc oxide-based composites with low dissolution and high antibacterial efficiency for pho-tocatalytic water disinfection,we prepared MoS_(2)/ZnO@CS composites via a precipitation method to encapsulate chitosan(CS)around MoS_(2)/ZnO.The amino groups in the CS molecules act as storerooms for hydrogen ions,which inhibits the dissolution of zinc oxide.In addition,the MoS_(2)/ZnO@CS composites exhibit high production of reactive oxygen species(ROS)and broad-spectrum antibacterial activity under simulated solar irradiation(0.1 W·cm^(-2)).This makes it an excellent antibacterial agent for solar disinfection in water treatment.展开更多
The ability to replicate the microenvironment of the human body through the fabrication of scaffolds is a significant achievement in the biomedical field.However,the search for the ideal scaffold is still in its infan...The ability to replicate the microenvironment of the human body through the fabrication of scaffolds is a significant achievement in the biomedical field.However,the search for the ideal scaffold is still in its infancy and there are significant challenges to overcome.In the modern era,the scientific community is increasingly turned to natural substances due to their superior biological ability,lower cost,biodegradability,and lower toxicity than synthetic lab-made products.Chitosan is a well-known polysaccharide that has recently garnered a high amount of attention for its biological activities,especially in 3D bone tissue engineering.Chitosan closely matches the native tissues and thus stands out as a popular candidate for bioprinting.This review focuses on the potential of chitosan-based scaffolds for advancements and the drawbacks in bone treatment.Chitosan-based nanocomposites have exhibited strong mechanical strength,water-trapping ability,cellular interaction,and biodegradability.Chitosan derivatives have also encouraged and provided different routes for treatment and enhanced biological activities.3D tailored bioprinting has opened new doors for designing and manufacturing scaffolds with biological,mechanical,and topographical properties.展开更多
Electrospinning has gained significant importance across various fields,including biomedicine,filtration,and packaging due to the control it provides over the properties of the resulting materials,such as fiber diamet...Electrospinning has gained significant importance across various fields,including biomedicine,filtration,and packaging due to the control it provides over the properties of the resulting materials,such as fiber diameter and membrane thickness.Chitosan is a biopolymer that can be utilized with both natural and synthetic copolymers,owing to its therapeutic potential,biocompatibility,and biodegradability.However,producing electrospun chitosan is challenging due to its high solution viscosity,which often results in the formation of beads instead of uniform fibers.To address this issue,the spinnability of chitosan is significantly enhanced,and the production of continuous nanofibers is facilitated by combining it with polymers such as polyethylene oxide(PEO)in suitable ratios.These chitosan–PEO nanofibers are primarily used in biomedical applications,including wound healing,drug delivery systems,and tissue engineering scaffolds.Additionally,they have shown promise in water treatment,filtration membranes,and packaging.Among all the nanofiber mats,chitosan/PEO-AC had the smallest fiber diameter(83±12.5 nm),chitosan/PEO_45S5 had the highest tensile strength(1611±678 MPa).This comprehensive review highlights recent advancements,ongoing challenges,and future directions in the electrospinning of chitosan-based fibers assisted by PEO.展开更多
CRISPR-Cas system permanently deletes any harmful gene-of-interest to combat cancer growth.Chitosan(CS)is a potential cancer therapeutic that mediates via PI3K/Akt/mTOR,MAPK and NF-kβsignaling pathway modulation.CS a...CRISPR-Cas system permanently deletes any harmful gene-of-interest to combat cancer growth.Chitosan(CS)is a potential cancer therapeutic that mediates via PI3K/Akt/mTOR,MAPK and NF-kβsignaling pathway modulation.CS and its covalent derivatives have been designed as nanocarrier of CRISPR-Cas9 alone(plasmid or ribonucleoprotein)or in combination with chemical drug for cancer treatment.The nanocarrier was functionalized with polyethylene glycol(PEG),targeting ligand,cell penetrating ligand and its inherent positive zeta potential to mitigate premature clearance and particulate aggregation,and promote cancer cell/nucleus targeting and permeabilization to enable CRISPR-Cas9 acting on the host DNA.Different physicochemical attributes are required for the CS-based nanocarrier to survive from the administration site,through the systemic circulation-extracellular matrix-mucus-mucosa axis,to the nucleus target.CRISPR-Cas9 delivery is met with heterogeneous uptake by the cancer cells.Choice of excipients such as targeting ligand and PEG may be inappropriate due to lacking overexpressed cancer receptor or availability of excessive metabolizing enzyme and immunoglobulin that defies the survival and action of these excipients rendering nanocarrier fails to reach the target site.Cancer omics analysis should be implied to select excipients which meet the pathophysiological needs,and chitosan nanocarrier with a“transformative physicochemical behavior”is essential to succeed CRISPR-Cas9 delivery.展开更多
MicroRNAs(miRNAs)are abundant in the brain and mounting evidence suggests their involvement in the critical processes such as neurodevelopment,synaptic plasticity,and the development of neurodegenerative diseases.Thus...MicroRNAs(miRNAs)are abundant in the brain and mounting evidence suggests their involvement in the critical processes such as neurodevelopment,synaptic plasticity,and the development of neurodegenerative diseases.Thus,miRNAs may be promising therapeutic drugs for the treatment of neurodegenerative disorders.However,naked miRNAs are not able to enter cells directly,especially brain cells.Therefore,suitable carriers for safe and efficient miRNA delivery to brain cells are of great importance.Chitosan nanoparticles,with the excellent properties such as good compatibility and brilliant degradability,may act as a promising carrier for miRNA drug delivery.In this study,chitosan nanoparticles were prepared and their properties such as particle size,zeta potential and encapsulation efficiency were optimized to encapsulate miRNAs.The delivery efficiency of miRNA-loaded nanoparticles was then evaluated in both neuronal and microglia cells.The results demonstrated chitosan nanoparticles encapsulated miRNAs efficiently and showed excellent sustained releasing in vitro.Moreover,chitosan nanoparticles delivered miRNA to both neurons and microglia with very low toxicity and high efficiency.In conclusion,chitosan nanoparticles are promising carriers for the delivery of miRNAs to brain cells,which may be used for the early intervention and treatment of neurodegenerative disorders.展开更多
Objective:To develop chitosan-silver nanoparticles targeting Pseudomonas aeruginosa biofilms and verify their antibacterial performance through animal experiments.Methods:Chitosan,silver nitrate,glacial acetic acid,an...Objective:To develop chitosan-silver nanoparticles targeting Pseudomonas aeruginosa biofilms and verify their antibacterial performance through animal experiments.Methods:Chitosan,silver nitrate,glacial acetic acid,and other chemical reagents were used to synthesize chitosan-silver nanoparticles.The characterization,minimum inhibitory concentration,and biofilm inhibition rate of the chitosan-silver nanoparticles were tested.A total of 40 SD rats were randomly divided into four groups.After routine adaptive feeding,the control group received intraperitoneal injection of normal saline;the model group received intraperitoneal injection of Pseudomonas aeruginosa suspension;the positive group received intraperitoneal injection of Pseudomonas aeruginosa suspension mixed with ampicillin at a volume ratio of 1∶1;the observation group received intraperitoneal injection of Pseudomonas aeruginosa suspension mixed with chitosan-silver nanoparticles(at minimum inhibitory concentration)at a volume ratio of 1∶1.Bacterial load,inflammatory factors,and liver and kidney function indicators in tissues were observed and compared among the four groups on the 3^(rd)day after treatment.Results:When the concentration of chitosansilver nanoparticles reached 8μg/mL or above,the OD value of the experimental wells was close to that of the control wells,indicating that 8μg/mL was the minimum inhibitory concentration of the chitosan-silver nanoparticles;at concentrations of 8μg/mL or above,the biofilm inhibition rate was greater than 80%.The bacterial load in the observation group was significantly lower than that in the model and positive groups(P<0.05).The expression levels of interleukin-6,interferon-γ,and tumor necrosis factor-αin the observation group were significantly lower than those in the model and positive groups(P<0.05).There were no statistically significant differences in alanine aminotransferase,aspartate aminotransferase,blood urea nitrogen,and creatinine levels among the four groups(P>0.05).Conclusion:The chitosan-silver nanoparticles targeting Pseudomonas aeruginosa biofilms constructed in this study exhibit good antibacterial effects against Pseudomonas aeruginosa and have good safety.展开更多
The continuous increase in petroleum-based plastic food packaging has led to numerous environmental concerns.One effort to reduce the use of plastic packaging in food is through preservation using biopolymer-based pac...The continuous increase in petroleum-based plastic food packaging has led to numerous environmental concerns.One effort to reduce the use of plastic packaging in food is through preservation using biopolymer-based packaging.Among the many types of biopolymers,chitosan is widely used and researched due to its non-toxic,antimicrobial,and antifungal properties.Chitosan is widely available since it is a compound extracted from seafood waste,especially shrimps and crabs.The biodegradability and biocompatibility of chitosan also showed good potential for various applications.These characteristics and propertiesmake chitosan an attractive biopolymer to be implemented as food packaging in films and coatings.Chitosan has been tested in maintaining and increasing the shelf life of food,especially seafood such as fish and shrimp,and post-harvest products such as fruits and vegetables.In addition to its various advantages,the properties and characteristics of chitosan need to be improved to produce optimal preservation.The properties and characteristics of chitosan are improved by adding various types of additive materials such as biopolymers,plant extracts,essential oils,and metal nanoparticles.Research shows that material additives and nanotechnology can improve the quality of chitosan-based food packaging for various types of food by enhancing mechanical properties,thermal stability,antimicrobial activity,and antioxidant activity.This review provides a perspective on the recent development and properties enhancement of chitosan composite with additives and nanotechnology,as well as this material’s challenges and prospects as food packaging.展开更多
A significant portion of losses in the fruit and vegetable sector are caused by the necrotrophic fungus Botrytis cinerea,due to its high prevalence in over 1000 crop species.Identifying a technology capable of exclusi...A significant portion of losses in the fruit and vegetable sector are caused by the necrotrophic fungus Botrytis cinerea,due to its high prevalence in over 1000 crop species.Identifying a technology capable of exclusively inhibiting its growth and development remains challenging;therefore,various treatments have been proposed to act synergistically in preventing the spread of this pathogen.The objective of this study was to evaluate an ultrasound-assisted treatment combined with chitosan to control the development of B.cinerea.In vitro analyses showed that combining temperature,ultrasound,and chitosan inhibited the fungal radial growth by 80%,reduced sporulation,and decreased germination.Electrolyte leak analysis indicated damage to the B.cinerea cell wall,causing intracellular material to escape into the environment.Scanning and transmission electron microscopy images also revealed severe structural damage,including loss of the cytoplasmic membrane and cell lysis.展开更多
Biodegradable plastics are types of plastics that can decompose into water and carbon dioxide the actions of living organisms,mostly by bacteria.Generally,biodegradable plastics are obtained from renewable raw materia...Biodegradable plastics are types of plastics that can decompose into water and carbon dioxide the actions of living organisms,mostly by bacteria.Generally,biodegradable plastics are obtained from renewable raw materials,microorganisms,petrochemicals,or a combination of all three.This study aims to develop an innovative bioplastic by combining chitosan and lignin.Bioplastic was prepared by casting method and characterized by measuring the mechanical properties like tensile strength,Young’smodulus,and elongation at break.The chemical structure,together with the interactions among chitosan and lignin and the presence of new chemical bonds,were evaluated by FTIR,while the thermal properties were assessed by thermogravimetric analysis.The water vapor permeability,tests and transparency as well as biodegradability,were also carried out.The results show a tensile strength value of 34.82 MPa,Young’s modulus of 18.54 MPa,and elongation at a break of 2.74%.Moreover,the interaction between chitosan and lignin affects the intensity of the absorption peak,leading to reduced transparency and increased thermal stability.The chitosan/lignin interactions also influence the crystalline size,making it easier to degrade andmore flexible rather than rigid.The contact angle shows the bioplastic’s ability to resist water absorption for 4minutes.In the biodegradation test,the sample began to degrade after 30 days of soil burial test observation.展开更多
Background:Spinal cord injury(SCI),which often results from traumatic incidents,leads to neural damage and impaired sensory and motor functions and may pose a serious threat to life.Secondary injury mechanisms caused ...Background:Spinal cord injury(SCI),which often results from traumatic incidents,leads to neural damage and impaired sensory and motor functions and may pose a serious threat to life.Secondary injury mechanisms caused by persistent inflammation disrupt the local microenvironment,causing neuronal cell death and hindering neural regeneration.This study used a chitosan-citric acid(CS-CA)hydrogel as a carrier for Catalpol(CAT-CS-CA),which was directly applied to the injury site to promote SCI repair.Methods:CAT-CS-CA and CS-CA hydrogels were characterized and implanted into rat SCI models.Fifty-four male Sprague-Dawley rats(230-250 g)rats were involved in the experiment.Six rats were randomly divided into two groups(n=3 per group)for in vivo degradation of hydrogels.Forty-eight rats were randomly assigned into four groups(n=12)using a randomization protocol:sham operation group(laminectomy only),SCI group,CS-CA hydrogel group,and CAT-CS-CA hydrogel group.From each group,3 rats were randomly selected for serum and spinal cord tissue extraction,followed by ELISA and RT-qPCR assays to determine the expression levels of various inflammatory factors(IL-1β,IL-6,TNF-α,and IL-10).Another 3 randomly selected rats were used for the evaluation of hindlimb motor function.The remaining 6 rats in each group were used to detect the expression of neuronal nuclei(NeuN),βIII-tubulin(Tuj1),glial fibrillary acidic protein(GFAP),and macrophage polarization(M1/M2 markers).Results:The CAT-CS-CA hydrogel retains CS-CA hydrogel's advantages and gains enhanced neuroprotective and anti-inflammatory abilities.The implantation of CAT-CS-CA into injured rat spinal cords enhanced neuronal survival,stimulated axonal regeneration,and significantly suppressed glial proliferation at the injury site.In addition,it promoted macrophage polarization to the M2 phenotype and substantially enhanced hindlimb motor function in rats with SCI.Conclusion:CAT-CS-CA hydrogel promotes neuronal survival,suppresses glial scarring,and improves motor function,offering a promising strategy for SCI repair.展开更多
Rechargeable aqueous zinc(Zn)-metal batteries hold great promise for next-generation energy storage systems.However,their practical application is hindered by several challenges,including dendrite formation,corrosion,...Rechargeable aqueous zinc(Zn)-metal batteries hold great promise for next-generation energy storage systems.However,their practical application is hindered by several challenges,including dendrite formation,corrosion,and the competing hydrogen evolution reaction.To address these issues,we designed and fabricated a composite protective layer for Zn anodes by integrating carbon nanotubes(CNTs)with chitosan through a simple and scalable scraping process.The CNTs ensure uniform electric field distribution due to their high electrical conductivity,while protonated chitosan regulates ion transport and suppresses dendrite formation at the anode interface.The chitosan/CNTs composite layer also facilitates smooth Zn^(2+)deposition,enhancing the stability and reversibility of the Zn anode.As a result,the chitosan/CNTs@Zn anode demonstrates exceptional cycling stability,achieving over 3000 h of plating/stripping with minimal degradation.When paired with a V_(2)O_(5)cathode,the composite-protected anode significantly improves the cycle stability and energy density of the full cell.Techno-economic analysis confirms that batteries incorporating the chitosan/CNTs protective layer outperform those with bare Zn anodes in terms of energy density and overall performance under optimized conditions.This work provides a scalable and sustainable strategy to overcome the critical challenges of aqueous Zn-metal batteries,paving the way for their practical application in next-generation energy storage systems.展开更多
Synthesis of zinc oxide nanoparticles(ZnO-NPs)via green method is an outstanding alternative to conventional/regular methods;however,the safety or toxicity of the biosynthesized ZnO-NPs in vivo is not fully explored.T...Synthesis of zinc oxide nanoparticles(ZnO-NPs)via green method is an outstanding alternative to conventional/regular methods;however,the safety or toxicity of the biosynthesized ZnO-NPs in vivo is not fully explored.This study was conducted to evaluate the protective efficiency of cinnamaldehyde-loaded chitosan nanoparticles(Cin@CSNPs)against oxidative damage and genotoxicity of ZnO-NPs in mice.ZnO-NPs were biosynthesized using the extract of fresh leaves of Mentha pulegium L.Cin was extracted from cinnamon essential oil,and was loaded into chitosan nanoparticle(Cin@CSNPs).Both ZnO-NPs,Cin@CSNPs and CSNPs were characterized.The in vitro release of Cin@CSNPs was determined.In the biological study,6 groups of male BALB/c mice were treated by gavage for 3 weeks as follows,control group,the group received ZnO-NPs(25 mg/kg b.w),the groups received Cin@CSNPs at low dose(50 mg/kg b.w)or high dose(100 mg/kg b.w),and the groups received ZnO-NPs plus Cin@CSNPs at the 2 tested doses.Blood and tissue samples were collected for different biochemical,genetical and histological studies.The particle size of ZnO-NPs,CSNPs,and Cin@CSNPs were(20.78±2.60),(170.0±3.7),and(218.23±2.90)nm,andξ-potential were(32.7±4.6),(8.32±0.27)and(4.80±0.21)mV,respectively.ZnO-NPs disturbed the biochemical and oxidative stress indices,AFP,CEA,TNF-α,chromosomal aberrations in somatic and germ cells,and sperm abnormality along with severe pathological changes in the hepatic,renal,and testicular tissues.Cin@CSNPs improved significantly all the parameters tested and the histological picture in a dose-dependent.Therefore,the biosynthesized ZnO-NPs exhibit oxidative damage and genotoxicity,and Cin@CSNPs have potential protective effects against the risks of ZnO-NPs and may be a promising tool to overcome the challenges of using Cin in food and pharmaceuticals applications.展开更多
Objective:To explore the impact of exogenous chitosan on the growth and metabolism of Glycyrrhiza uralensis Fisch.(G.uralensis)and to improve the quality of cultivated G.uralensis for both medicine and food and aid in...Objective:To explore the impact of exogenous chitosan on the growth and metabolism of Glycyrrhiza uralensis Fisch.(G.uralensis)and to improve the quality of cultivated G.uralensis for both medicine and food and aid in the increase in the content of effective components in G.uralensis.Methods:In this study,whole G.uralensis plants were treated with exogenous chitosan,and compre-hensive analyses of secondary metabolites and proteins were conducted using liquid chromatography with tandem mass spectrometry and isobaric tag for relative and absolute quantitation,respectively.Effects of chitosan induction on endogenous hormones of G.uralensis were analyzed using an enzyme-linked immunosorbent assay.Gene ontology function annotation and Kyoto Encyclopedia of Genes and Genomes pathway annotation were conducted to study the effect of chitosan induction on the proteome.Results:Chitosan induction significantly increased the levels of flavonoids in G.uralensis;however,the variation in triterpenoids was not substantial.Biological processes,including photosynthesis,secondary metabolism,and abiotic stress responses,were significantly enriched.Additionally,the photosynthetic pathway,photosynthesis-antenna protein pathway,and plant hormone signal transduction pathway were significantly enriched.In the flavonoid biosynthesis pathway,the upstream-related enzyme phenylalanine ammonia-lyase(PAL)and the downstream-related enzymes chalcone synthase(CHS),polyketide reductase(PKR),chalcone isomerase(CHI),and vestitone reductase(VR)were significantly upregulated.Conclusions:Our findings suggest that chitosan induction may promote the tricarboxylic acid(TCA)cycle,and the TCA cycle enhancement significantly upregulated PAL,CHS,PKR,CHI,and VR,the five key enzymes involved in flavonoid synthesis of G.uralensis,indicating that chitosan induction activated the entire metabolic pathway associated with flavonoids in G.uralensis.Our findings provide a reference for improving the quality of cultivated G.uralensis from the perspective of pharmacodynamic components.展开更多
Polylactic acid(PLA),a biodegradable polymer,exhibits superior mechanical strength and processability.However,its broader adoption is hindered by inherent brittleness,low hydrophilicity,and sluggish crystallization ki...Polylactic acid(PLA),a biodegradable polymer,exhibits superior mechanical strength and processability.However,its broader adoption is hindered by inherent brittleness,low hydrophilicity,and sluggish crystallization kinetics.Chitosan(CS),a natural polysaccharide renowned for its biocompatibility and biodegradability,offers potential to address these limitations.While both materials have garnered significant attention in materials science,research on their integration via melt blending and the resulting performance enhancements for food-contact plastics remains understudied.This research comprehensively explores how different levels of CS content,from 0% to 10%,impact the characteristics of chitosan/polylactic acid(CS/PLA)composites.It specifically analyzes the influence of various CS concentrations on the mechanical attributes,crystallization behavior,thermomechanical properties,and rheological performance of these composites.The study concludes that a CS content of 4% in the CS/PLA composite results in the best overall properties.At this point,its elongation at break and impact strength reached theirmaximum values(16.16% and 20.63 kJ/m^(2)),representing increases of 23.9% and 15.7% compared to pure PLA.At this particular concentration,CS is evenly distributed throughout the PLA matrix,acting as a heterogeneous nucleating agent.It facilitates the crystallization of the composite material and offers effective reinforcement.This study presents a promising approach for developing environmentally friendly and sustainable alternatives to fossil-based plastics,highlighting significant research value and practical application potential.展开更多
文摘The effects to elicit resistance reaction on oilseed rape (Brassica napus L. cv Xinongchangjiao ) by four partially N-acetylated chitosan 7B, 8B, 9B and 10B (Degree of acetylation (D. A.) is 30% , 20% , 10%, 0%, respectively) and Glycol chitosan (GC, D.A. is 0%) were investigated and compared. Results showed that chitosan were similar to salicylic acid (SA), and could induce resistance reaction, but the reaction was influenced by the degree of acetylation of chitosan. Fully deacetylated chitosans, 10B and GC, elicited chitinase activity, but partially acetylated chitosan, 7B, 8B and 9B, inhibited chitinase activity. Phenyalanine ammonia-lyase (PAL) was also elicited. Elicitor activity increased with on increasing degree of acetylation, 7B induced highest PAL activity among all chitosans. All chitosans induced peroxidase (POD) in a similar level. After elicited by glycol chitosan, like SA treatment, the seedlings increased disease resistance to Sclerotinia sclerotiorum significantly.
基金This work was supported by the National Natural Science Foundation of China (No. 50173019).
文摘Original chitosan with M-v of 2.7 x 10(5) was degraded by irradiation with gamma-rays and a series of low molecular weight O-carboxymethylated chitosans (O-CMCh) were prepared based on the irradiated chitosan. A kinetic model of the irradiation of chitosan was put forward. Results show that the irradiation degradation of chitosan obeys the rule of random degradation and the degree of deacetylation of irradiated chitosan is slightly raised. The antibacterial activity of O-CMCh is significantly influenced by its MW, and a suppositional antibacterial peak appears when M-v is equal to 2 x 10(5).
基金supported by the National Natural Science Foundation of China(Nos.20920102035,20974086, and 21074083)the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)
文摘The purpose of this research is to investigate the effects of the variously sulfated chitosans on lysozyme activity and structure. It was shown that the specific enzymatic activity of lysozyme remained almost similar to the native protein after being bound to 6-O-sulfated chitosan （6S-chitosan） and 3,6-O-sulfated chitosan （3,6S-chitosan）, but decreased greatly after being bound to 2-N-6-O-sulfated chitosan （2,6S-chitosan）. Meanwhile, among these sulfated chitosans, 2,6S-chitosan induced the greatest conformational change in lysozyme as indicated by the fluorescence spectra. These findings demonstrated that when sulfated chitosans of different structures bind to lysozyme, lysozyme undergoes conformational change of different magnitudes, which results in corresponding levels of lysozyme activity. Further study on the interaction of sulfated chitosans with lysozyme by surface plasmon resonance （SPR） suggested that their affinities might be determined by their molecular structures.
基金supported by the Development Project of Science and Technology of Qingdao(02-1-Kchhh-58)National‘863’High Technology Project of China(819-07-03)
文摘Five kinds of carboxymethyl sulfochitosans with different regions such as N-carboxymethyl-O-sulfochitosan, O-carboxymethyl-N-sulfochitosan, O-carboxymethyl chitosan sulfate, N-carboxymethyl chitosan-6-sulfate, and N,O-carboxymethyl -N,O-sulfochitosan were prepared respectively by using differential carboxymethylation and sulfation methods, and their IR spectrum and 13C-NMR spectrum were measured.
文摘Chitosan is a biopolymer obtained from chitin, where the N-acetylglucosamine monomer is in its deacetylated form; this polymer is useful for a wide variety of industrial applications. The properties and uses of chitosan depend on its physical and chemical characteristics, which result from the treatments used for its production. In this study, we report the preparation and characterization ofchitosan oligosaccharides by a green synthesis from crystalline shrimp chitin, using a sequential enzyme treatment by chitinase and chitin deacetylase. Chitinases were purified from grapes and used to rupture the crystalline shrimp chitin structure, modifying the crystallinity index from 57.6% to 15.9%. The resultant polymers were deacetylated using a recombinant chitin deacetylase from Saccharomyces cerevisiae, which was cloned and expressed in Pichia pastoris. The chitosans produced showed an estimated DA （degree of acetylation） of approximately 20%, and the molecular weights ranged from -7,600 to -3,700 after treatment in pH 3.0 and pH 6.0 for 10 min and 40 min, respectively. Physical and chemical characterization of the products indicated that enzyme fragmentation of chitin probably makes the acetamide groups more accessible to deacetylation, forming homogeneous polymers that are free of hazardous sub-products, have defined low molecular weights, and are highly deacetylated.
文摘The potent antibacterial activity of silver nanoparticles is primarily attributed to the release of silver ions,which disrupt cell membranes and inactivate essential enzymes through Ag−S bonding formation.[Objective]To explore silver ion immobilization to minimize silver release.[Methods]A macrocyclic cryptand with nitrogen bridgeheads was prepared and subsequently chelated with silver ions to produce Cage silver(I),which was then coordinated with different ratios of sulfonated chitosan(SCS)to form SCS/Cage Ag(I)complexes(SCA1,SCA2,and SCA3).The antioxidant activities of the complexes were assessed by reducing power and 1,1-diphenyl-2-picrylhydrazyl(DPPH)free radical and hydrogen peroxide scavenging assays.The antibacterial activities of the complexes were evaluated based on the minimum inhibitory concentrations(MICs)and minimum bactericidal concentrations(MBCs)against Staphylococcus aureus ATCC 6538 and Escherichia coli O157:H7 and the inhibition rate on biofilm formation.[Results]Cage silver(I)exhibited strong antibacterial activity,with the MIC of 0.015 mg/mL and MBC of 0.031 mg/mL against S.aureus ATCC 6538,and the MIC of 0.031 mg/mL and MBC of 0.120 mg/mL against E.coli O157:H7.Significant antioxidant properties of Cage silver(I)were also observed,as demonstrated by the DPPH free radical scavenging rates of 42.2%and 53.1%at 326 nm and 517 nm,respectively.Cage silver(I)exhibited the highest antibacterial and antioxidant activities,followed by SCA1,SCA2,SCA3,and SCS,because the content of silver ions in Cage silver(I)was 10-fold higher than that in SCA1.The antibacterial and antioxidant activities of SCA1 were better than those of Cage silver(I),which further indicated that the sulfonic groups of SCS may intensely coordinate with silver ions to exert synergistic effects.[Conclusion]Combining the merits of silver ions and SCS improves the bioavailability of the agent at microbicidal concentrations,minimizes the accumulation in the environment,and reduces treatment costs.The method developed herein offers a sustainable approach to enhance microbial control while minimizing the impact on the environment.
基金supported in part by the National Natural Science Foundation of China(12174366)Fundamental Re-search Funds for the Central Universities(WK3450000005)the Anhui Provincial Natural Science Foundation(2108085MC93).
文摘The combination of solar disinfection and photocatalysis technology presents a viable solution for eliminating harmful pathogenic microorganisms from water.However,some photocatalysts(e.g.,zinc oxide-based composites)are susceptible to pH-dependent dissolution in water,which can result in the loss of photocatalysts and additional environ-mental pollution.To obtain zinc oxide-based composites with low dissolution and high antibacterial efficiency for pho-tocatalytic water disinfection,we prepared MoS_(2)/ZnO@CS composites via a precipitation method to encapsulate chitosan(CS)around MoS_(2)/ZnO.The amino groups in the CS molecules act as storerooms for hydrogen ions,which inhibits the dissolution of zinc oxide.In addition,the MoS_(2)/ZnO@CS composites exhibit high production of reactive oxygen species(ROS)and broad-spectrum antibacterial activity under simulated solar irradiation(0.1 W·cm^(-2)).This makes it an excellent antibacterial agent for solar disinfection in water treatment.
文摘The ability to replicate the microenvironment of the human body through the fabrication of scaffolds is a significant achievement in the biomedical field.However,the search for the ideal scaffold is still in its infancy and there are significant challenges to overcome.In the modern era,the scientific community is increasingly turned to natural substances due to their superior biological ability,lower cost,biodegradability,and lower toxicity than synthetic lab-made products.Chitosan is a well-known polysaccharide that has recently garnered a high amount of attention for its biological activities,especially in 3D bone tissue engineering.Chitosan closely matches the native tissues and thus stands out as a popular candidate for bioprinting.This review focuses on the potential of chitosan-based scaffolds for advancements and the drawbacks in bone treatment.Chitosan-based nanocomposites have exhibited strong mechanical strength,water-trapping ability,cellular interaction,and biodegradability.Chitosan derivatives have also encouraged and provided different routes for treatment and enhanced biological activities.3D tailored bioprinting has opened new doors for designing and manufacturing scaffolds with biological,mechanical,and topographical properties.
文摘Electrospinning has gained significant importance across various fields,including biomedicine,filtration,and packaging due to the control it provides over the properties of the resulting materials,such as fiber diameter and membrane thickness.Chitosan is a biopolymer that can be utilized with both natural and synthetic copolymers,owing to its therapeutic potential,biocompatibility,and biodegradability.However,producing electrospun chitosan is challenging due to its high solution viscosity,which often results in the formation of beads instead of uniform fibers.To address this issue,the spinnability of chitosan is significantly enhanced,and the production of continuous nanofibers is facilitated by combining it with polymers such as polyethylene oxide(PEO)in suitable ratios.These chitosan–PEO nanofibers are primarily used in biomedical applications,including wound healing,drug delivery systems,and tissue engineering scaffolds.Additionally,they have shown promise in water treatment,filtration membranes,and packaging.Among all the nanofiber mats,chitosan/PEO-AC had the smallest fiber diameter(83±12.5 nm),chitosan/PEO_45S5 had the highest tensile strength(1611±678 MPa).This comprehensive review highlights recent advancements,ongoing challenges,and future directions in the electrospinning of chitosan-based fibers assisted by PEO.
基金MOHE (FRGS/1/2023/STG05/UITM/01/3) for funding support
文摘CRISPR-Cas system permanently deletes any harmful gene-of-interest to combat cancer growth.Chitosan(CS)is a potential cancer therapeutic that mediates via PI3K/Akt/mTOR,MAPK and NF-kβsignaling pathway modulation.CS and its covalent derivatives have been designed as nanocarrier of CRISPR-Cas9 alone(plasmid or ribonucleoprotein)or in combination with chemical drug for cancer treatment.The nanocarrier was functionalized with polyethylene glycol(PEG),targeting ligand,cell penetrating ligand and its inherent positive zeta potential to mitigate premature clearance and particulate aggregation,and promote cancer cell/nucleus targeting and permeabilization to enable CRISPR-Cas9 acting on the host DNA.Different physicochemical attributes are required for the CS-based nanocarrier to survive from the administration site,through the systemic circulation-extracellular matrix-mucus-mucosa axis,to the nucleus target.CRISPR-Cas9 delivery is met with heterogeneous uptake by the cancer cells.Choice of excipients such as targeting ligand and PEG may be inappropriate due to lacking overexpressed cancer receptor or availability of excessive metabolizing enzyme and immunoglobulin that defies the survival and action of these excipients rendering nanocarrier fails to reach the target site.Cancer omics analysis should be implied to select excipients which meet the pathophysiological needs,and chitosan nanocarrier with a“transformative physicochemical behavior”is essential to succeed CRISPR-Cas9 delivery.
基金supported financially by the NSFC(Nos.62075098 and 62071119)the National Key Research and Development Program of China(Nos.2017YFA0205301 and 2018YFC1602905)。
文摘MicroRNAs(miRNAs)are abundant in the brain and mounting evidence suggests their involvement in the critical processes such as neurodevelopment,synaptic plasticity,and the development of neurodegenerative diseases.Thus,miRNAs may be promising therapeutic drugs for the treatment of neurodegenerative disorders.However,naked miRNAs are not able to enter cells directly,especially brain cells.Therefore,suitable carriers for safe and efficient miRNA delivery to brain cells are of great importance.Chitosan nanoparticles,with the excellent properties such as good compatibility and brilliant degradability,may act as a promising carrier for miRNA drug delivery.In this study,chitosan nanoparticles were prepared and their properties such as particle size,zeta potential and encapsulation efficiency were optimized to encapsulate miRNAs.The delivery efficiency of miRNA-loaded nanoparticles was then evaluated in both neuronal and microglia cells.The results demonstrated chitosan nanoparticles encapsulated miRNAs efficiently and showed excellent sustained releasing in vitro.Moreover,chitosan nanoparticles delivered miRNA to both neurons and microglia with very low toxicity and high efficiency.In conclusion,chitosan nanoparticles are promising carriers for the delivery of miRNAs to brain cells,which may be used for the early intervention and treatment of neurodegenerative disorders.
文摘Objective:To develop chitosan-silver nanoparticles targeting Pseudomonas aeruginosa biofilms and verify their antibacterial performance through animal experiments.Methods:Chitosan,silver nitrate,glacial acetic acid,and other chemical reagents were used to synthesize chitosan-silver nanoparticles.The characterization,minimum inhibitory concentration,and biofilm inhibition rate of the chitosan-silver nanoparticles were tested.A total of 40 SD rats were randomly divided into four groups.After routine adaptive feeding,the control group received intraperitoneal injection of normal saline;the model group received intraperitoneal injection of Pseudomonas aeruginosa suspension;the positive group received intraperitoneal injection of Pseudomonas aeruginosa suspension mixed with ampicillin at a volume ratio of 1∶1;the observation group received intraperitoneal injection of Pseudomonas aeruginosa suspension mixed with chitosan-silver nanoparticles(at minimum inhibitory concentration)at a volume ratio of 1∶1.Bacterial load,inflammatory factors,and liver and kidney function indicators in tissues were observed and compared among the four groups on the 3^(rd)day after treatment.Results:When the concentration of chitosansilver nanoparticles reached 8μg/mL or above,the OD value of the experimental wells was close to that of the control wells,indicating that 8μg/mL was the minimum inhibitory concentration of the chitosan-silver nanoparticles;at concentrations of 8μg/mL or above,the biofilm inhibition rate was greater than 80%.The bacterial load in the observation group was significantly lower than that in the model and positive groups(P<0.05).The expression levels of interleukin-6,interferon-γ,and tumor necrosis factor-αin the observation group were significantly lower than those in the model and positive groups(P<0.05).There were no statistically significant differences in alanine aminotransferase,aspartate aminotransferase,blood urea nitrogen,and creatinine levels among the four groups(P>0.05).Conclusion:The chitosan-silver nanoparticles targeting Pseudomonas aeruginosa biofilms constructed in this study exhibit good antibacterial effects against Pseudomonas aeruginosa and have good safety.
基金Penelitian Tesis Magister(PTM)Research Grant from Indonesian Government Kemdikbudristek with contract number 036/E5/PG.02.00.PL/2024.PPM1 2024 Research Grant from Faculty of Industrial Technology,ITB.
文摘The continuous increase in petroleum-based plastic food packaging has led to numerous environmental concerns.One effort to reduce the use of plastic packaging in food is through preservation using biopolymer-based packaging.Among the many types of biopolymers,chitosan is widely used and researched due to its non-toxic,antimicrobial,and antifungal properties.Chitosan is widely available since it is a compound extracted from seafood waste,especially shrimps and crabs.The biodegradability and biocompatibility of chitosan also showed good potential for various applications.These characteristics and propertiesmake chitosan an attractive biopolymer to be implemented as food packaging in films and coatings.Chitosan has been tested in maintaining and increasing the shelf life of food,especially seafood such as fish and shrimp,and post-harvest products such as fruits and vegetables.In addition to its various advantages,the properties and characteristics of chitosan need to be improved to produce optimal preservation.The properties and characteristics of chitosan are improved by adding various types of additive materials such as biopolymers,plant extracts,essential oils,and metal nanoparticles.Research shows that material additives and nanotechnology can improve the quality of chitosan-based food packaging for various types of food by enhancing mechanical properties,thermal stability,antimicrobial activity,and antioxidant activity.This review provides a perspective on the recent development and properties enhancement of chitosan composite with additives and nanotechnology,as well as this material’s challenges and prospects as food packaging.
文摘A significant portion of losses in the fruit and vegetable sector are caused by the necrotrophic fungus Botrytis cinerea,due to its high prevalence in over 1000 crop species.Identifying a technology capable of exclusively inhibiting its growth and development remains challenging;therefore,various treatments have been proposed to act synergistically in preventing the spread of this pathogen.The objective of this study was to evaluate an ultrasound-assisted treatment combined with chitosan to control the development of B.cinerea.In vitro analyses showed that combining temperature,ultrasound,and chitosan inhibited the fungal radial growth by 80%,reduced sporulation,and decreased germination.Electrolyte leak analysis indicated damage to the B.cinerea cell wall,causing intracellular material to escape into the environment.Scanning and transmission electron microscopy images also revealed severe structural damage,including loss of the cytoplasmic membrane and cell lysis.
基金funded by the joint research collaboration of the Research Organization of Agriculture and Food National Research and Innovation Agency(BRIN)FY 2024(Grant number:6/III.11/HK/2024),with Widya Fatriasari as the Principal Investigator.
文摘Biodegradable plastics are types of plastics that can decompose into water and carbon dioxide the actions of living organisms,mostly by bacteria.Generally,biodegradable plastics are obtained from renewable raw materials,microorganisms,petrochemicals,or a combination of all three.This study aims to develop an innovative bioplastic by combining chitosan and lignin.Bioplastic was prepared by casting method and characterized by measuring the mechanical properties like tensile strength,Young’smodulus,and elongation at break.The chemical structure,together with the interactions among chitosan and lignin and the presence of new chemical bonds,were evaluated by FTIR,while the thermal properties were assessed by thermogravimetric analysis.The water vapor permeability,tests and transparency as well as biodegradability,were also carried out.The results show a tensile strength value of 34.82 MPa,Young’s modulus of 18.54 MPa,and elongation at a break of 2.74%.Moreover,the interaction between chitosan and lignin affects the intensity of the absorption peak,leading to reduced transparency and increased thermal stability.The chitosan/lignin interactions also influence the crystalline size,making it easier to degrade andmore flexible rather than rigid.The contact angle shows the bioplastic’s ability to resist water absorption for 4minutes.In the biodegradation test,the sample began to degrade after 30 days of soil burial test observation.
基金supported by the Medicine health science and technology development program of Shandong Province(202403070969)。
文摘Background:Spinal cord injury(SCI),which often results from traumatic incidents,leads to neural damage and impaired sensory and motor functions and may pose a serious threat to life.Secondary injury mechanisms caused by persistent inflammation disrupt the local microenvironment,causing neuronal cell death and hindering neural regeneration.This study used a chitosan-citric acid(CS-CA)hydrogel as a carrier for Catalpol(CAT-CS-CA),which was directly applied to the injury site to promote SCI repair.Methods:CAT-CS-CA and CS-CA hydrogels were characterized and implanted into rat SCI models.Fifty-four male Sprague-Dawley rats(230-250 g)rats were involved in the experiment.Six rats were randomly divided into two groups(n=3 per group)for in vivo degradation of hydrogels.Forty-eight rats were randomly assigned into four groups(n=12)using a randomization protocol:sham operation group(laminectomy only),SCI group,CS-CA hydrogel group,and CAT-CS-CA hydrogel group.From each group,3 rats were randomly selected for serum and spinal cord tissue extraction,followed by ELISA and RT-qPCR assays to determine the expression levels of various inflammatory factors(IL-1β,IL-6,TNF-α,and IL-10).Another 3 randomly selected rats were used for the evaluation of hindlimb motor function.The remaining 6 rats in each group were used to detect the expression of neuronal nuclei(NeuN),βIII-tubulin(Tuj1),glial fibrillary acidic protein(GFAP),and macrophage polarization(M1/M2 markers).Results:The CAT-CS-CA hydrogel retains CS-CA hydrogel's advantages and gains enhanced neuroprotective and anti-inflammatory abilities.The implantation of CAT-CS-CA into injured rat spinal cords enhanced neuronal survival,stimulated axonal regeneration,and significantly suppressed glial proliferation at the injury site.In addition,it promoted macrophage polarization to the M2 phenotype and substantially enhanced hindlimb motor function in rats with SCI.Conclusion:CAT-CS-CA hydrogel promotes neuronal survival,suppresses glial scarring,and improves motor function,offering a promising strategy for SCI repair.
基金supported by the National Natural Science Foundation of China(22279139,62227815,22465026,22469015)the National Key R&D Program of China(2022YFA1504500)+1 种基金the Natural Science Foundation of Inner Mongolia Autonomous Region of China(2024JQ06,2022MS2010,2024MS05005)Inner Mongolia University Postgraduate Scientific Research Innovation Project(11200-5223737)。
文摘Rechargeable aqueous zinc(Zn)-metal batteries hold great promise for next-generation energy storage systems.However,their practical application is hindered by several challenges,including dendrite formation,corrosion,and the competing hydrogen evolution reaction.To address these issues,we designed and fabricated a composite protective layer for Zn anodes by integrating carbon nanotubes(CNTs)with chitosan through a simple and scalable scraping process.The CNTs ensure uniform electric field distribution due to their high electrical conductivity,while protonated chitosan regulates ion transport and suppresses dendrite formation at the anode interface.The chitosan/CNTs composite layer also facilitates smooth Zn^(2+)deposition,enhancing the stability and reversibility of the Zn anode.As a result,the chitosan/CNTs@Zn anode demonstrates exceptional cycling stability,achieving over 3000 h of plating/stripping with minimal degradation.When paired with a V_(2)O_(5)cathode,the composite-protected anode significantly improves the cycle stability and energy density of the full cell.Techno-economic analysis confirms that batteries incorporating the chitosan/CNTs protective layer outperform those with bare Zn anodes in terms of energy density and overall performance under optimized conditions.This work provides a scalable and sustainable strategy to overcome the critical challenges of aqueous Zn-metal batteries,paving the way for their practical application in next-generation energy storage systems.
基金supported by the National Research Centre,Dokki,Cairo,Egypt project#13050302.
文摘Synthesis of zinc oxide nanoparticles(ZnO-NPs)via green method is an outstanding alternative to conventional/regular methods;however,the safety or toxicity of the biosynthesized ZnO-NPs in vivo is not fully explored.This study was conducted to evaluate the protective efficiency of cinnamaldehyde-loaded chitosan nanoparticles(Cin@CSNPs)against oxidative damage and genotoxicity of ZnO-NPs in mice.ZnO-NPs were biosynthesized using the extract of fresh leaves of Mentha pulegium L.Cin was extracted from cinnamon essential oil,and was loaded into chitosan nanoparticle(Cin@CSNPs).Both ZnO-NPs,Cin@CSNPs and CSNPs were characterized.The in vitro release of Cin@CSNPs was determined.In the biological study,6 groups of male BALB/c mice were treated by gavage for 3 weeks as follows,control group,the group received ZnO-NPs(25 mg/kg b.w),the groups received Cin@CSNPs at low dose(50 mg/kg b.w)or high dose(100 mg/kg b.w),and the groups received ZnO-NPs plus Cin@CSNPs at the 2 tested doses.Blood and tissue samples were collected for different biochemical,genetical and histological studies.The particle size of ZnO-NPs,CSNPs,and Cin@CSNPs were(20.78±2.60),(170.0±3.7),and(218.23±2.90)nm,andξ-potential were(32.7±4.6),(8.32±0.27)and(4.80±0.21)mV,respectively.ZnO-NPs disturbed the biochemical and oxidative stress indices,AFP,CEA,TNF-α,chromosomal aberrations in somatic and germ cells,and sperm abnormality along with severe pathological changes in the hepatic,renal,and testicular tissues.Cin@CSNPs improved significantly all the parameters tested and the histological picture in a dose-dependent.Therefore,the biosynthesized ZnO-NPs exhibit oxidative damage and genotoxicity,and Cin@CSNPs have potential protective effects against the risks of ZnO-NPs and may be a promising tool to overcome the challenges of using Cin in food and pharmaceuticals applications.
基金supported by grants from the National Natural Science Foundation of China(81773838).
文摘Objective:To explore the impact of exogenous chitosan on the growth and metabolism of Glycyrrhiza uralensis Fisch.(G.uralensis)and to improve the quality of cultivated G.uralensis for both medicine and food and aid in the increase in the content of effective components in G.uralensis.Methods:In this study,whole G.uralensis plants were treated with exogenous chitosan,and compre-hensive analyses of secondary metabolites and proteins were conducted using liquid chromatography with tandem mass spectrometry and isobaric tag for relative and absolute quantitation,respectively.Effects of chitosan induction on endogenous hormones of G.uralensis were analyzed using an enzyme-linked immunosorbent assay.Gene ontology function annotation and Kyoto Encyclopedia of Genes and Genomes pathway annotation were conducted to study the effect of chitosan induction on the proteome.Results:Chitosan induction significantly increased the levels of flavonoids in G.uralensis;however,the variation in triterpenoids was not substantial.Biological processes,including photosynthesis,secondary metabolism,and abiotic stress responses,were significantly enriched.Additionally,the photosynthetic pathway,photosynthesis-antenna protein pathway,and plant hormone signal transduction pathway were significantly enriched.In the flavonoid biosynthesis pathway,the upstream-related enzyme phenylalanine ammonia-lyase(PAL)and the downstream-related enzymes chalcone synthase(CHS),polyketide reductase(PKR),chalcone isomerase(CHI),and vestitone reductase(VR)were significantly upregulated.Conclusions:Our findings suggest that chitosan induction may promote the tricarboxylic acid(TCA)cycle,and the TCA cycle enhancement significantly upregulated PAL,CHS,PKR,CHI,and VR,the five key enzymes involved in flavonoid synthesis of G.uralensis,indicating that chitosan induction activated the entire metabolic pathway associated with flavonoids in G.uralensis.Our findings provide a reference for improving the quality of cultivated G.uralensis from the perspective of pharmacodynamic components.
基金funded by National Natural Science Foundation of China(NSFC),grant number(No.U2341237).
文摘Polylactic acid(PLA),a biodegradable polymer,exhibits superior mechanical strength and processability.However,its broader adoption is hindered by inherent brittleness,low hydrophilicity,and sluggish crystallization kinetics.Chitosan(CS),a natural polysaccharide renowned for its biocompatibility and biodegradability,offers potential to address these limitations.While both materials have garnered significant attention in materials science,research on their integration via melt blending and the resulting performance enhancements for food-contact plastics remains understudied.This research comprehensively explores how different levels of CS content,from 0% to 10%,impact the characteristics of chitosan/polylactic acid(CS/PLA)composites.It specifically analyzes the influence of various CS concentrations on the mechanical attributes,crystallization behavior,thermomechanical properties,and rheological performance of these composites.The study concludes that a CS content of 4% in the CS/PLA composite results in the best overall properties.At this point,its elongation at break and impact strength reached theirmaximum values(16.16% and 20.63 kJ/m^(2)),representing increases of 23.9% and 15.7% compared to pure PLA.At this particular concentration,CS is evenly distributed throughout the PLA matrix,acting as a heterogeneous nucleating agent.It facilitates the crystallization of the composite material and offers effective reinforcement.This study presents a promising approach for developing environmentally friendly and sustainable alternatives to fossil-based plastics,highlighting significant research value and practical application potential.
