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OBJECTIVE: Poor healing is one of the major complications of microbial contamination of wounds. When the skin is damaged, microorganisms can quickly invade the underlying tissues and cause infections that are potentially life-threatening. As a result, effective therapies are required to handle such pathological disorders. Several bioactivities, including fungicidal and antibacterial properties, have been noted for Eucalyptus essential oils. This study aimed to investigate the effect of Eucalyptus oil (EO) and mixed oils (MO) of Eucalyptus citriodora, citronellol acetate, linalool, and α-pinene on the healing of C. albicans infected wounds in rats. MATERIALS AND METHODS: Essential oils were extracted from the fresh areal parts of Eucalyptus citriodora, Lavandula stricta, and Rosmarinus officinalis then their active compounds were chromatographically isolated and identified using GC/Ms. The in vitro antifungal activities of EO and MO were evaluated against Candida albicans using the Agar well diffusion method. Further, their effect on the healing of C. albicans infected wounds was evaluated via the excision wound rat's model. Percentages of wound contraction, epithelialization period, wound Candida load, and the histopathology of wounded tissues were evaluated to confirm the progression of wound healing. RESULTS: Results of the in vitro tests showed that MO has a potent activity against C. albicans evaluated by an inhibitory zone (IZ) diameter of 23.4 mm and a MIC value of 0.24 g/mL, compared to EO's corresponding values of 13.4 mm and 15.63 g/mL. The beneficial impacts of MO creams in improving the percentage of contraction of C. albicans contaminated wounds were better than those of EO creams. MO 10% cream showed the greatest proportion of wound contraction and epithelialization rate. The beneficial effect of MO was further confirmed by a significant reduction of the fungal load of wounds in addition to histopathological improvement compared to the NC group. CONCLUSIONS: This study suggested the potential of 10% MO cream in enhancing the healing of C. albicans infected wounds upon topical application. [ABSTRACT FROM AUTHOR]

Different methods can be used for nanofibers fabrication such as bicomponent extrusion, template synthesis, self assembly, phase separation, meltblowing. drawing, electrospinning and centrifugal spinning. These fibers have numerous applications such as reinforcement fibers in composites, protective clothing, filiration, biomedical devices, electrical and optical applications, and nanosensors. This review paper sheds light upon production techniques of nanofibers, their physical properties and production parameters affecting these properties. Since electrospinning is still the most well known and widely used method for producing nanofibers, the effect of its parameters on nanofiber properties were also reviewed extensively. [ABSTRACT FROM AUTHOR]

ZnAl 2 O 4 and CuAl 2 O 4 spinel nanoparticles were prepared by a modified Pechini method and used with the natural chitosan (CS) and shellac (SH) polymers to form novel composite membranes as promising food packaging materials. The selection of ZnAl 2 O 4 and CuAl 2 O 4  spinel nanoparticles was based on their antibacterial characteristics, availability, and economy. Using a straightforward and adaptable solution mixing and casting method, the bio-composites were created. The mechanical, physical, antibacterial, homogeneity and air permeability properties of composite films were investigated. The film structure was evaluated in terms of component interactions using FTIR spectra. The addition of 10% SH increased the tensile strength, percentage strain at maximum load, Young's modulus, and burst strength by 114-101%, 3.6-8.4, 103-119, and 179-153% for low and middle M.wt./CS respectively. Chitosan/shellac-CuAl 2 O 4  composite has superior properties compared to ZnAl 2 O 4  composite. In general, 0.05% spinel provides a composite having better qualities than that of 0.1 additions. Middle M.wt. chitosan provides a composite with superior properties compared to that of low M.wt. The incorporation of ZnAl 2 O 4 or CuAl 2 O 4 enhanced the thermal stability of the SH/CS composite. ZnAl 2 O 4 provides superior thermal stability than CuAl 2 O 4 . When shellac/CS film structure is treated with the previously indicated ZnAl 2 O 4 or CuAl 2 O 4 formulation, the % swelling decreases along with an increasing in the gel fraction. The antimicrobial assessment using inhibition zone diameter and shake flask methods showed that a composite of 1:9 shellac/chitosan/0.05% of CuAl 2 O 4 exerted the highest Gram-positive antibacterial activity against B. mycoides (21 mm), and C. albicans (22 mm). So, these enhancements make chitosan/shellac/ZnAl 2 O 4 or CuAl 2 O 4  composite films a good alternative to producing food packaging materials., Competing Interests: Competing interests The authors declare no competing interests., (© 2024. The Author(s).)

This work aims to apply carbon quantum dots (CQDs) from agriculture cellulosic waste (agro wastes), produced via an economically and eco-friendly single-step method, to be used into cellulose acetate composite microfibrous membranes as an innovative solution specifically designed to adsorb methylene blue (MB) and other cationic dyes that are present in various water effluents. Batch adsorption tests were conducted, with variations in contact time (1-24 h), initial MB concentration (25-300 ppm), and adsorbent doses (1-20 g/L). The maximum adsorption capacity of the membrane was 198 mg/g with an initial concentration of 300 ppm at 298 K. Thermodynamic parameters showed that the process is endothermic. Equilibrium experimental data for MB adsorption onto electrospun adsorbent were fitted using different isothermal models, with the Freundlich model showing the best fit. The pseudo-second-order model accurately described the kinetic data with high reliability (R 2  > 0.99), and the calculated adsorption capacity was very close to the experimental data. N-CQDs loaded membranes were also tested for removing methyl violet and rhodamine B, demonstrating remarkably high dye removal efficiency. The underlying adsorption mechanism was also reported. Finally, it is worth mentioning that composite adsorbents can be efficiently applied to actual industrial cases because of the possibility of reusing them, opening the route to the fabrication of novel and highly performant adsorbents. These findings underscore N-CQDs' effectiveness in enhancing pollutant removal efficiency from wastewater, highlighting their environmental benefits and promoting a more sustainable approach to water treatment. Therefore, the prepared adsorbent, showing excellent adsorption performance, places them among adsorbents for practical applications in wastewater purification., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Background : Employing citric acid/dimethyl formamide (CA/DMF), two distinct types of carbon quantum dots (CQDs), tree-shaped/fingerprinted (TF-CQDs) and fullerene-like (F) were synthesized from both cellulose and carboxymethyl cellulose (CMC). Methods : Fluorescence microscopy revealed different emission colors: blue for TF-CQDs and green for F, highlighting the structural influence on light properties. Transmission electron microscopy (TEM) confirmed the intricate fingerprinted and tree-like morphology of TF-CQDs and the spherical nature of F derived from CMC. The adsorption behavior and kinetics of Cr(vi) removal from water by TF-CQDs and F were evaluated. Significant findings : Both samples demonstrated rapid Cr(vi) uptake; TF-CQDs reached equilibrium within 120 minutes compared to 240 minutes for F. Subsequent leaching led to decreased adsorption after these initial periods. Kinetic analysis revealed a first-order model for TF-CQDs, implying physical adsorption dominance. Conversely, F exhibited a better fit to pseudo-first and second-order models, suggesting combined chemical and physical mechanisms., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

This study reports a novel, eco-friendly; fast and cost-effective microwave method for synthesizing carboxymethylated graphene oxide (CMGO) from sugarcane residues. Fourier-transform infrared spectroscopy (FTIR) confirmed successful CMGO synthesis through the presence of characteristic peaks at 1567.93 and 1639.29 cm -1 (COONa vibrations) and increased CH 2 intensity compared to unmodified graphene oxide (GO). Furthermore, CMGO derived from sugarcane residues demonstrated potential in mitigating the side effects of toxic materials like carbon tetrachloride (CCl 4 ). Treatment with CMGO partially reduced elevated levels of liver enzymes (ALT and AST) and nitrogenous waste products (urea and uric acid) in CCl 4 -induced liver damage models, suggesting an improvement in liver function despite ongoing cellular damage.This work paves the way for a sustainable and economical approach to produce functionalized graphene oxide with promising biomedical applications in alleviating toxin-induced liver injury., (© 2024. The Author(s).)

We report the ionothermal carbonization (ITC) of lignocellulosic biomass in imidazolium tetrachloroferrate ionic liquids (ILs) as an advantageous approach for the preparation of nanostructured carbonaceous materials, namely, ionochars. In a previous study, we investigated the role of the imidazolium cation and demonstrated the possibility of controlling both the textural and morphological properties of ionochars by cation engineering. Although essential for providing intermediate Lewis acidity and relatively high thermal stability, the role of the chloroferrate anion is still open to debate. Herein, we investigated the ITC of sugarcane bagasse and its main component, cellulose, in 1-alkyl-3-methylimidazolium ILs with different chloroferrate anions. We identified anionic speciation and its impact on the properties of the IL by Raman spectroscopy, thermogravimetric analysis, and differential scanning calorimetry. The obtained ionochars were characterized by gas physisorption, electron microscopy, Raman spectroscopy, Fourier transform infrared (FTIR) spectroscopy, and 13 C solid-state CP-MAS NMR spectroscopy. We show that the anionic species have a predominant impact on the textural and morphological properties of the ionochars.

This work aims to enhance the performance of the polyvinyl alcohol (PVA) composite by using cellulose nanocrystal (CNC) as reinforcement and copper nanoparticles (CuNPs)/reduced graphene oxide (rGO) as conducting and antimicrobial reagents. Firstly, rGO was loaded onto CuNPs using an eco-friendly microwave method. Different techniques characterized the components and prepared composites, which indicated the incorporation of cellulose nanocrystals and rGO@CuNPs within the polyvinyl alcohol matrix. Utilizing the clear zone of inhibition, the antibacterial test was quantified. Compared to the neat composite, the rGO@CuNPs loaded polyvinyl alcohol/ cellulose nanocrystal composites exhibited no bacterial growth against S. aureus, E. coli, and C. albicans. However, all composites did not have antifungal activity against A. niger. The combination of conductivity and interfacial polarization is the reason for the abrupt increase of permittivity with decreasing frequency. Besides, adding rGO@CuNPs improved the electrical conductivity. DC-Conductivity increased about a decade after adding cellulose nanocrystal to polyvinyl alcohol, then another decade after adding CuONPs. The electric loss modulus representation shows a systematic shift in the peak position towards higher frequencies, decreasing the so-called conductivity relaxation time. This is the main reason for the enhancement of conductivity. The systematic attenuation of peaks' height with increasing conductivity is still unclear., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have influenced the work reported in this paper., (Copyright © 2024. Published by Elsevier B.V.)

Graphene oxide (GO), TiO 2 -NPs, HPMC, and shellac are environmentally green polymers and nanocomposites. This work aimed to create biodegradable composite films made of HPMC/shellac, HPMC/shellac-GO, and HPMC/shellac-GO/TiO 2 -NPs by film casting. TiO 2 -HPMC/shellac-GO matrix's dispersibility and mixing ability were characterized and observed using FTIR and XRD. XRD analysis shows that the crystallinity decreased within the composites due to breaking H-bonding. Compared to HPMC/shellac, TGA/DTG demonstrated the composite films' superior thermal stability. TiO 2 (0.08-0.16 %) was cast into a composite film comprising HPMC, shellac, and GO. The homogeneity of TiO 2 distribution in the composite film was shown using a SEM, which was also used to display the morphology of nanocomposite films. Nanocomposite films' thickness, air permeability, tensile strength, Young's modulus, and burst strength were examined. The results demonstrated that natural films prepared by a combination of shellac/GO with HPMC enhanced the fabricating of films' properties, the tensile strength increased by 231 % (from 16 to 53 MPa) in HPMC and HPSG2 (HPMC 1.9 g/shellac 0.25 g/GO 0.125 g in 100 mL) respectively, whereas the contact angle did not change. And after addition of TiO 2 -NPs, there were high enhancements in HPMC films' properties, such tensile strength increased by 212 % (from 16 to 50 MPa), burst strength increased by 20.96 % (3.1 to 3.75 Kg/cm 2 ), and the contact angle by 60.86 % (48 to 74°) in HPMC and HPSGT2 respectively. Compared to HPMC films, films exhibited the highest levels of antibacterial activity against E. coli, B. mycoides, and C. albicans. So, the composite films from HPMC/shellac/GO/TiO 2 -NPs are promising potential packaging materials., Competing Interests: Declaration of competing interest The authors declare no competing interests., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Due to its excellent antiseptic efficacy and antimicrobial properties, propolis has shown attractive advantages in wound dressings. However, an inclusive review of the propolis-based materials as a wound dressing is still lacking. The current short review summarizes the skin wound healing process, relates evaluation parameters, and then reviews the refined propolis-based materials dressings such as antimicrobial property, adhesion and hemostasis, anti-inflammatory and substance delivery. The approaches implemented to achieve these functions are classified and discussed. Furthermore, applications of propolis wound dressing for treating different types of wounds such as heal wounds, burns, and ulcers are presented. The future directions of propolis-based wound dressings for wound healing are further proposed. This review showed that propolis-based materials might be a promising new dressing for wound occlusion and tissue repairing., (© 2023. The Author(s).)

A combination of different eco-friendly materials prepared promising fluorescent quantum dots (QDs) through the one-step process using the microwave heating of urea with cellulose, chitosan, and biochar. Characterizations of the prepared QDs, including the investigation of their structure by infrared spectroscopy, Raman analysis, X-ray diffraction, thermal gravimetric analysis, morphology, and optical properties, were performed. The results showed that QDs possess a small size, high UV absorption, and excitation wavelength-dependent fluorescence. The prepared QDs were also tested for metal ions removal from aqueous solutions. The adsorption at different contact times was investigated to optimize the adsorption efficiency of the prepared QDs. All QDs were found to be an ideal sorbent for Cr(II), Cu(II), Mn(II), and Pb(II). From the data, Cr(II) was more highly adsorbed than other metal ions. The results of the kinetic investigation showed that the pseudo-second-order kinetic model fit the adsorption process effectively. In addition, the fluorescence spectra of QDs were changed after the adsorption of metal ions; hence, the prepared QDs could be utilized in environmental sectors such as wastewater pollution detection, adsorption, and chemical sensing applications.

The chromium adsorption behavior from aqueous solution by the amphoteric Janus nitrogen-doped carbon quantum dots (AJ-N-CQDs) was investigated. The pseudo-first-order and the second-order adsorption kinetics models were employed to analyze the experimental data; the second-order adsorption kinetics model presented a better correlation to the experimental data, suggesting a chemisorptions process. The values obtained in the pseudo-first-order are still suitable for describing the Kinetics of Cr(VI) sorption. These values elucidate the surface processes involving chemisorption and physisorption in the adsorption of Cr(VI) by AJ-N-CQDs. The R 2 of the Boyd model gave a better fit to the adsorption data of AJ-N-CQDs (i.e., external diffusion), which means the surface processes involving external Cr(VI) adsorption by AJ-N-CQDs. The higher value of α may be due to the greater surface area of the AJ-N-CQDs for the immediate adsorption of Cr(VI) from the aqueous solution. AJ-N-CQDs have fluorescence spectra before and after Cr(VI) adsorption, indicating they are promising for chemical sensor applications., (© 2023. The Author(s).)

Biopolymers have significant pharmaceutical applications, and their blending has favorable characteristics for their pharmaceutical properties compared to the sole components. In this work, sodium alginate (SA) as a marine biopolymer was blended with poly(vinyl) alcohol (PVA) to form SA/PVA scaffolds through the freeze-thawing technique. Additionally, polyphenolic compounds in Moringa oleifera leaves were extracted by different solvents, and it was found that extracts with 80% methanol had the highest antioxidant activity. Different concentrations (0.0-2.5%) of this extract were successfully immobilized in SA/PVA scaffolds during preparation. The characterization of the scaffolds was carried out via FT-IR, XRD, TG, and SEM. The pure and Moringa oleifera extract immobilized SA/PVA scaffolds (MOE/SA/PVA) showed high biocompatibility with human fibroblasts. Further, they showed excellent in vitro and in vivo wound healing capacity, with the best effect noted for the scaffold with high extract content (2.5%).

A novel adsorbent from cationic chitosan derivative and anionic silica precursor was fabricated to remove methylene blue (MB). The hybrid material was prepared from N-guanidinium chitosan acetate (GChi) and carboxyethylsilanetriol sodium salt by a simple ionic interaction followed by sol-gel approach. Multiple characterization methods were used to analyze the morphology and the structure of the well-prepared functionalized material. Batch experiments were conducted to optimize the various operational parameters. The Langmuir isotherm was used to fit the data, and it predicted monolayer adsorption with a maximum capacity of 334 mg g -1 . A pseudo-second-order equation fit the adsorption process well. Chitosan/silica hybrids containing carboxylic groups are efficient and cost-effective adsorbents for cationic dyes adsorption from aqueous solutions., (© 2023. The Author(s).)

In this work, we prepared highly swelling, stimuli-responsive hydrogels capable of the highly efficient adsorption of inorganic pollutants. The hydrogels were based on hydroxypropyl methyl cellulose (HPMC) grafted with acrylamide (AM) and 3-sulfopropyl acrylate (SPA) and were synthesized via the growth (radical polymerization) of the grafted copolymer chains on HPMC, which was activated by radical oxidation. These grafted structures were crosslinked to an infinite network by a small amount of di-vinyl comonomer. HPMC was chosen as a cheap hydrophilic and naturally sourced polymer backbone, while AM and SPA were employed to preferentially bond coordinating and cationic inorganic pollutants, respectively. All the gels displayed a pronounced elastic character, as well as considerably high values of stress at break (several hundred %). The gel with the highest fraction of the ionic comonomer SPA (with an AM/SPA ratio = 0.5) displayed the highest equilibrium swelling ratio (12,100%), the highest volume response to temperature and pH, and the fastest swelling kinetics, but also the lowest modulus. The other gels (with AM/SPA = 1 and 2) displayed several times higher moduli but more modest pH responses and only very modest temperature sensitivity. Cr(VI) adsorption tests indicated that the prepared hydrogels removed this species from water very efficiently: between 90 and 96% in one step. The hydrogels with AM/SPA ratios of 0.5 and 1 appeared to be promising regenerable (via pH) materials for repeated Cr(VI) adsorption.

In the current work, we present a renewable alternative coating formulation made of durable titania nanoparticles and oxidized nanocellulose (TiO 2 NPs@OCNs) nanocomposites and sodium alginate (SA), to create an environmentally friendly and secure food packaging paper. OCNs sugarcane fibers are firstly hydrolyzed using ammonium persulphate (APS). Then, TiO 2 NPs@OCNs nanocomposites are made in situ with OCNs using a green water-based sol-gel synthesis. Gram (+) microorganisms as well as Gram (-) bacteria are used to test the antibacterial properties of the TiO 2 NPs@OCN dispersions. The results show that the TiO 2 NP@OCNs significantly decreases the growth for all bacterial species. The TiO 2 NP@OCNs nanocomposites are mixed with SA, and the resulting formulations are used to coat paper sheets. The corresponding physicochemical properties are evaluated using FTIR, TGA, AFM, SEM, and EDX. Furthermore, the mechanical strength, air permeability, and water vapor characteristics of the paper sheets treated with SA/TiO 2 NPs@OCN are carried out, resulting in a great improvement of these properties. Finally, the SA/TiO 2 NPs@OCNs coated papers have been used as packaging for strawberries. The findings demonstrate that coated papers could preserve strawberry quality better than unpacked fruit and extend strawberry shelf life from 6 to 18 days., Competing Interests: Declaration of competing interest The authors declare that there are no conflicts of interest., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Fluorescent carbon quantum dots (CQDs) were prepared by an economical, green, and single-step procedure with the assistance of microwave heating of urea with bagasse (SCB), cellulose (C), or carboxymethyl cellulose (CMC). The prepared CQDs were characterized using a series of spectroscopic techniques, and they had petite size, intense absorption in the UV, and excitation wavelength-dependent fluorescence. The prepared CQDs were used for Pb(II) adsorption from an aqueous solution. The removal efficiency percentages (R %) were 99.16, 96.36, and 98.48% for QCMC, QC, and QSCB, respectively. The findings validated the efficiency of CQDs synthesized from CMC, cellulose, and SCB as excellent materials for further utilization in the environmental fields of wastewater pollution detection, adsorption, and chemical sensing applications. The kinetics and isotherms studied found that all CQDs isotherms fit well with the Langmuir model than Freundlich and Temkin models. According to R 2 , the pseudo-second-order fits the adsorption of QCMC, while the first-order one fits with QC and QSCB., (© 2022. The Author(s).)

In this study, we have used hydroxyethyl cellulose (HEC) to prepare antimicrobial films for multipurpose applications. Using HEC gives mangiferin powder (M) mechanical properties, while mangiferin powder gives HEC antimicrobial activities. Various concentrations of M (2.5, 5 and 10% wt/vol) were added to HEC to enhance the antimicrobial ability of HEC/M films. The results showed that 10% (wt/vol) was the optimum concentration to accomplish the antimicrobial activity. Various analyses were performed to study the prepared films' physical, chemical, mechanical, and antimicrobial properties., (© 2022. The Author(s).)

Aim: This study aims to prepare a nanocomposite (HPMC/5-FL@GO) from hydroxypropyl methylcellulose (HPMC) and graphene oxide (GO) as biocompatible materials. The nanocomposite enhances the drug activity of immobilized 5-fluorouracil (5-FU), decreasing the side effect of long-run treatment protocols with highly efficient drug-drug activity., Method and Results: Different samples were characterized by ATR-FTIR spectroscopy, X-ray diffraction, scanning electron microscopy coupled with energy dispersive X-ray analysis, transmission electron microscopy, thermogravimetric analysis, and dynamic light scattering along with cytotoxicity and anticancer study. A homogenous and compatible nanocomposite structure with a homogenous drug distribution was confirmed. Furthermore, the prepared nanocomposite has a low cytotoxicity effect against normal Vero cell lines compared with 5-FU. The antitumor activities of the same nanocomposite (20.4 and 74.3 μg mL -1 on A549 and HepG-2) were lower than that of 5-FU (54.1 and 103 μg mL -1 on A549 and HepG-2)., Conclusion and Implications: According to the attained results, the HPMC/5-FL@GO can apply in a biomedical application such as cancer therapy with the unique biocompatible to human cells., (© 2021 Wiley-VCH GmbH.)

Packaging is as important as the product itself because it is a crucial marketing and communication tool for business. Oxidized nanocellulose (ONC), extracted from agriculture residues of bagasse raw material using ecofriendly ammonium persulfate hydrolysis method, is used as support/reducing agent for the generation of silver nanoparticles (AgNPs) via photochemical procedure and reinforcing element in paper functionalization. The natural polymer, sodium alginate (SA) is exploited to enhance the binding of the ONC-AgNPs over cellulose fibers. The SA/ONC-AgNPs bio-nanocomposite is incorporated on paper matrix, which represents a more suitable choice respect to other substrates for its renewable, biocompatible, biodegradable, and cost-effective properties. Structural and antimicrobial evaluations show that the papers embedded with the SA/ONC-AgNPs possess good mechanical, thermal, barrier and antibacterial properties., Competing Interests: Declaration of competing interest There is no conflict of interest in this paper., (Copyright © 2021 Elsevier B.V. All rights reserved.)