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Pseudomonas aeruginosa bacteria originate severe infections in hospitalized patients and those with chronic debilitating diseases leading to increased morbidity and mortality, longer ...hospitalization and huge financial burden to the healthcare system. The clinical relevance of P. aeruginosa infections is increased by the capability of this bacterium to grow in biofilms and develop multidrug resistant mechanisms that preclude conventional antibiotic treatments. Herein, we engineered novel multimodal nanocomposites that integrate in the same entity antimicrobial silver nanoparticles (NPs), the intrinsically antimicrobial, but biocompatible biopolymer chitosan, and the anti-infective quorum quenching enzyme acylase I. Acylase present in the NPs specifically degraded the signal molecules governing bacterial cell-to-cell communication and inhibited by ∼ 55 % P. aeruginosa biofilm formation, while the silver/chitosan template altered the integrity of bacterial membrane, leading to complete eradication of planktonic bacteria. The innovative combination of multiple bacteria targeting modalities resulted in 100-fold synergistic enhancement of the antimicrobial efficacy of the nanocomposite at lower and non-hazardous towards human skin cells concentrations, compared to the silver/chitosan NPs alone.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
In this study, a multifunctional food packaging material (G-Eug-NPs-NF) based on gelatin nanofiber membranes (G-NF) containing eugenol nanoparticles (Eug-NPs) were prepared. The Eug-NPs were ...fabricated through the electrostatic self-assembly by using two ionic polysaccharides chitosan and sulfobutylether-β-cyclodextrin (SCD). Compared with G-NF, the G-Eug-NPs-NF exhibited better antioxidant capacity, which positively correlated with Eug-IC concentration, up to 84.17%. In addition, the latter had a good inhibitory effect on Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus), and was more conducive to inhibit the growth of S. aureus. At the same time, the sustained release experiment showed that the incorporation of Eug-NPs in nanofiber membranes improved the sustained release ability of G-Eug-NPs-NF. G-Eug-NPs-NF exhibits the promising application of Eug in food, medicine and other fields.
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•Eug-NPs were prepared by electrostatic self-assembly of CS and inclusion complex (Eug-IC).•G-Eug-NPs-NF were prepared by electrospinning method of Eug-NPs.•G-Eug-NPs-NF exhibited better antioxidant capacity, and can inhibit bacterial growth.•The incorporation of Eug-NPs in nanofiber membranes improved the sustained release ability of G-Eug-NPs-NF.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Infection is one of the main causes of orthopedic implants failure, with antibiotic-resistant bacteria playing a crucial role in this outcome. In this work, antimicrobial nanogels were developed to ...be applied in situ as implant coating to prevent orthopedic-device-related infections. To that regard, a broad-spectrum antimicrobial peptide, Dhvar5, was grafted onto chitosan via thiol–norbornene “photoclick” chemistry. Dhvar5-chitosan nanogels (Dhvar5-NG) were then produced using a microfluidic system. Dhvar5-NG (1010 nanogels (NG)/mL) with a Dhvar5 concentration of 6 μg/mL reduced the burden of the most critical bacteria in orthopedic infections - methicillin-resistant Staphylococcus aureus (MRSA) – after 24 h in medium supplemented with human plasma proteins. Transmission electron microscopy showed that Dhvar5-NG killed bacteria by membrane disruption and cytoplasm release. No signs of cytotoxicity against a pre-osteoblast cell line were verified upon incubation with Dhvar5-NG. To further explore therapeutic alternatives, the potential synergistic effect of Dhvar5-NG with antibiotics was evaluated against MRSA. Dhvar5-NG at a sub-minimal inhibitory concentration (109 NG/mL) demonstrated synergistic effect with oxacillin (4-fold reduction: from 2 to 0.5 μg/mL) and piperacillin (2-fold reduction: from 2 to 1 μg/mL). This work supports the use of Dhvar5-NG as adjuvant of antibiotics to the prevention of orthopedic devices-related infections.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
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•Gabapentin loaded chitosan nanoparticles (107 nm) prepared using Nano Spray Dryer.•Intranasal Rhodamine labeled chitosan nanoparticles exhibited high brain uptake.•Nose-brain ...delivery of gabapentin overcomes poor oral bioavailability problem.•Intranasal spray dried optimized formulation showed promising seizure treatment.
In the present study, gabapentin (GBP)-loaded chitosan nanosized particles were fabricated applying the nanospray drying technique. Different preparation parameters (spray mesh diameter, chitosan concentration and presence of D-α-Tocopherol polyethylene glycol 1000 succinate (TPGS) were studied while fixing other parameters (spraying rate, inlet temperature and gas flow rate). An optimized formulation with a particle size 107 ± 13 nm was obtained upon spraying 0.1% (w/v) chitosan solution containing 0.05% (w/v) of TPGS utilizing the small nozzle (4 μm spray mesh hole size). Drug entrapment efficiency and yield were as high as 95% and 83%, respectively. A 98.1 ± 6.1% (w/w) cumulative drug release was recorded after 2 h. Confocal laser scanning microscopy showed higher fluorescent dye penetration into brain tissue following intranasal administration of Rhodamine B labeled spray dried chitosan nanoparticles (NPs) as compared to Rhodamine B solution. Pentylenetetrazole (PTZ) was used to induce convulsions in rats through elevating seizure stages, releasing neuroinflammatory mediators and reducing excitatory amino acid transporter 2 (EAAT 2) and γ-aminobutyric acid (GABA) brain contents. Nanospray dried GBP-loaded chitosan NPs reduced seizure score, neuroinflammation; TNF-α and TGF-β, elevated EAAT 2 and GABA as well as decreased degeneration in pyramidal neurons compared to marketed product Conventin® capsules. Thus, it can be concluded from the aforementioned data that nanospray dried GBP-loaded chitosan NPs could comprise an appropriate treatment of epilepsy.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
We report the preparation of curcumin-integrated chitosan nanoparticles (CNP@Cur) and utilize them to fabricate functional films based on mixed biopolymers (pullulan and chitosan). Curcumin is a ...well-known bioactive functional filler in food packaging, so we developed CNP@Cur as a functional nanofiller. The fabricated nanofillers were approximately spherical with a size of about 20–50 nm, as observed by FE-SEM. Additionally, the developed CNP@Cur was very stable in an aqueous solution (zeta potential ∼50 mV). The chemical interaction of curcumin and chitosan was checked using FTIR spectra and XRD. The bio-based active packaging film was fabricated by adding different content of CNP@Cur (0, 1, 2 & 4 wt%) to the pullulan/chitosan (50:50) polymer matrices using a solution casting process. The addition of functional nanofillers remarkably enhanced the mechanical strength (∼15 %), UV-light shielding properties (∼80 %), and hydrophobicity (∼18 %) without much reducing the transparency (∼20 %) of the film. The water vapor barrier property of the film was also slightly improved. In addition, CNP@Cur on nanocomposite films showed significant improvement in antioxidant activity (DPPH and ABTS assays) and slightly increased antibacterial activity against E. coli and L. monocytogenes. Thus, blending bioactive functional nanofillers improved the bio-based film's physical and functional properties, which could be applied for active food packaging and biomedical purposes.
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•Curcumin-integrated chitosan nanoparticle (CNP@Cur) was developed.•Pullulan/chitosan-based functional composite film was prepared by adding CNP@Cur.•Mechanical, UV-light barrier properties of the film increased without sacrificing transparency.•Hydrophobicity and water vapor barrier properties of the film improved significantly.•The nanocomposite film exhibited potent antioxidant and antibacterial properties.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Chitosan nanoparticles (NPs) are promising polymeric and bio-based NPs, which have received a lot of attention in the last decades. They have great potential as nanocarriers that encapsulate ...substances such as drugs or active compounds, deliver them to a specific place or site, and provide a controlled release. In the present review, we give a complete overview of the preparation methods, including novel and green procedures, and compile developed applications in medicine, agriculture, and wastewater treatment. Moreover, we highlight the future perspective of chitosan NPs use in PLA-based biodegradable polymers which can be one of the solutions for reducing plastic pollution in nature. Properties of chitosan NPs can be tuned in such a way that they can serve as reinforcement elements in biodegradable plastics leading to much-needed improvements, and also as functional elements that make the application in food packaging with e.g., enhanced antimicrobial activity possible.
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•Chitosan nanoparticles are convenient carriers for drugs and active ingredients.•Chitosan properties can be adjusted with various modifications of structure.•Chitosan nanoparticles can enhance mechanical strength of biodegradable plastics.•Such nanocomposites allow widespread use of biodegradable plastics.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
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•Laccase and ABTS were co-immobilized on a novel support.•The biocatalyst was applied to various pollutants degradation.•Immobilized laccase showed higher enzyme loading and increased ...activity.•Immobilized laccase displayed superior enzymatic properties.•The biocatalyst showed high catalytic performance for pollutants in pure water.
This work aims to achieve the co-immobilization of laccase and 2,2-binamine-di-3-ethylbenzothiazolin-6-sulfonic acid (ABTS) to improve removal capability of the biocatalyst for pollutants while avoiding potential pollution caused by ABTS. The laccase was immobilized on magnetic chitosan nanoparticles modified with amino-functionalized ionic liquid containing ABTS (MACS-NIL) based on Cu ion chelation (MACS-NIL-Cu-lac). The carrier was characterized by Fourier transform infrared spectroscopy, thermogravimetric analysis, x-ray diffraction and etc., and electron paramagnetic resonance confirmed the mediator molecule ABTS on the carrier could also play the role of electron transmission. MACS-NIL-Cu-lac presented relatively high immobilization capacity, enhanced activity (1.7-fold that of free laccase), improved pH and temperature adaptability, and increased thermal and storage stability. The removal performance assay found that MACS-NIL-Cu-lac had a good removal efficiency with 100.0 % for 2,4-dichlorophenol in water at 25 °C, even when the concentration reached 50 mg/L. Reusability study showed that after six catalytic runs, the removal efficiency of 2,4-dichlorophenol by MACS-NIL-Cu-lac could still reach 93.2 %. Additionally, MACS-NIL-Cu-lac exhibited higher catalytic efficiencies with 100.0 %, 70.5 % and 93.3 % for bisphenol A, indole, and anthracene, respectively. The high catalytic performance in pure water system obtained by the novel biocatalyst co-immobilizing laccase and electron mediator ABTS showed greater practical application value.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Chitosan has been termed as the most well-known among biopolymers, receiving widespread attention from researchers in various fields mainly, agriculture, food, and health. Chitosan is a deacetylated ...derivative of chitin, mainly isolated from waste shells of the phylum Arthropoda after their consumption as food. Chitosan molecules can be easily modified for adsorption and slow release of plant growth regulators, herbicides, pesticides, and fertilizers, etc. Chitosan as a carrier and control release matrix that offers many benefits including; protection of biomolecules from harsh environmental conditions such as pH, light, temperatures and prolonged release of active ingredients from its matrix consequently protecting the plant's cells from the hazardous effects of burst release. In the current review, tends to discuss the recent advances in the area of chitosan application as a control release system. Also, future recommendations will be made in light of current advancements and major gaps.
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•Intensive use of agrochemical is harmful to both health and environment.•Biomaterials based controlled release can be a good strategy to overcome the problem.•Chitosan, an ecofriendly and economical polymer is a good option.•Chitosan based delivery systems for agrochemicals are favorable and efficient.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
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•Chitosan nanoparticles (CSNPs) were modified as antioxidant/antimicrobial additives.•Each CSNPs derivative provides different antioxidant and antimicrobial ability.•CSNPs-g-stearyl ...methacrylate showed outstanding antimicrobial action against E. coli.•CSNPs-deoxycholic acid showed excellent antioxidant activity.•Active CSNPs derivatives are suit for PLA compounding and bioplastic packaging.
Chitosan nanoparticles (CSNPs) based on their different derivatives were proposed as antioxidant and antimicrobial additives for active bioplastic packaging. Chitosan was modified with polyethylene glycol methyl ether methacrylate (PEGMA), stearyl methacrylate (SMA) and deoxycholic acid (DC) using radiation-induced graft polymerization and chemical conjugation. The modified CSNPs-g-pPEGMA, CSNPs-g-pSMA and CSNPs-DC self-assembled into nanoparticles with the size in the range of 25−60 nm. The CSNPs-DC derivative has superior antioxidant activity and the CSNPs-g-pSMA derivative exhibited outstanding antibacterial activity against growth of E.coli (95.33 %). All modified CSNPs showed their capacities to inhibit S.aureus bacterial growth (>98 %). PLA packaging films containing CSNPs-g-pSMA inhibited the growth of natural microorganism on bread slices. Different chemical functions of the CSNPs derivatives provided different gas permeability and mechanical properties of the PLA films. The CSNPs derivatives would be promising antioxidant and antimicrobial additives for bioplastics to be further used as bio-based active food packaging.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Effects of chitosan nanoparticles on biophysical characteristics and growth of Robusta coffee (Coffea canephora Piere var Robusta) in green house condition have been investigated. Chitosan ...nanoparticles with high molecular weight (600kDa) were prepared by nano spray drier. Effect of size and concentration of chitosan nanoparticles on biophysical characteristics such as photosynthetic net rate, transpiration of the leaves, contents of chlorophyll, carotenoid, nutrient uptake and growth parameters of the coffee were investigated. The results showed that chitosan nanoparticles with concentration of 10ppm effected strongly on biophysical and growth of coffee in the green house. Chitosan nanoparticles enhanced 30–50% content of chlorophyll in the coffee leaves, from 30 to 60% photosynthesis intensity in comparison to the control. Chitosan nanoparticles also increased in uptake of nutrients, such as 9.8–27.4% N, 17.3–30.4% P, 30–45% K. Chitosan nanoparticles also had significant impact on the growth of the coffee seedlings, growth parameters of treated coffee were higher than control. The results also showed that size effect of chitosan nanoparticles in the range from 420 to 970nm on biophysical characteristics and growth parameters of the coffee seedlings was not different significantly.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
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