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1.
Materials (Basel) ; 17(13)2024 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-38998269

RESUMO

In this study, a novel multifunctional biofilm was fabricated using a straightforward casting process. The biofilm comprised gelatin, chitosan, 5-fluorouracil (5-FU)-conjugated zinc oxide nanoparticles, and polyvinyl alcohol plasticized with glycerol. The 5-FU-conjugated nanoparticles were synthesized via a single-step co-precipitation process, offering a unique approach. Characterization confirmed successful drug conjugation, revealing bar-shaped nanoparticles with sizes ranging from 90 to 100 nm. Drug release kinetics followed the Korsmeyer-Peppas model, indicating controlled release behavior. Maximum swelling ratio studies of the gelatin-chitosan film showed pH-dependent characteristics, highlighting its versatility. Comprehensive analysis using SEM, FT-IR, Raman, and EDX spectra confirmed the presence of gelatin, chitosan, and 5-FU/ZnO nanoparticles within the biofilms. These biofilms exhibited non-cytotoxicity to human fibroblasts and significant anticancer activity against skin cancer cells, demonstrating their potential for biomedical applications. This versatility positions the 5-FU/ZnO-loaded sheets as promising candidates for localized topical patches in skin and oral cancer treatment, underscoring their practicality and adaptability for therapeutic applications.

2.
Int J Biol Macromol ; : 133131, 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38945721

RESUMO

Fresh-cut products are extremely perishable due to the processing operations, and the atmosphere environment, especially CO2, O2 and H2O, could profoundly affect their shelf life. Herein, an insect "lac blanket"-mimetic and facile strategy was proposed for fresh-cut vegetables preservation, employing porous shellac hydrogel microparticles as gas "switches" in chitosan film to regulate CO2, O2 and H2O vapor permeability. Thus, the shellac hydrogel/chitosan hybrid film presented the controllable and wide range of gas permeability, compared with the chitosan film. The shellac-COOH nanoscale vesicles aggregated to form shellac hydrogel network via hydrophobic binding. The shellac hydrogel microparticles played a certain lubricating effect on the hybrid film casting solution. The hydrogen bond network between shellac hydrogel and chitosan contributed to the excellent mechanical properties of the hybrid film. The hybrid film also exhibited remarkable water-resistant, antifogging properties, optical transparency and degradability. The hybrid packaging films prepared through this strategy could adjust the internal gas (CO2, O2, H2O and ethylene) contents within the packages, and further exhibited admirable preservation performance on three fresh-cut vegetables with different respiratory metabolisms. This gas permeation-controlled strategy has great potential in fresh food preservation and various other applications that need a modified atmosphere.

3.
Chem Biodivers ; : e202400645, 2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-38923658

RESUMO

Antimicrobial films were prepared with chitosan containing the methanolic extract of M. tenuiflora leaves (FECT20%, FECT30%, and FECT40%), and their antimicrobial activities were evaluated by agar diffusion. The films were characterized by IR spectroscopy, scanning electron microscopy (SEM) and TG/DTG curves. TG/DTG curves showed thermal stability of chitosan-extract films up to 166 ºC. Micrographs of chitosan-extract films revealed an increase in porosity with the addition of extract. The FECT40% film showed inhibition zone diameters (IZ) against Micrococcus luteus, Staphylococcus aureus, Bacillus subtilis, and B. cereus, ranging from 1.0 ± 0.02 to 0.72 ± 0.09 cm. Only FECT30% and FECT40% inhibited the P. aeruginosa with IZs of 0.68 ± 0.02 and 0.77 ± 0.06 cm, respectively. In turn, the extract showed inhibition against B. subtilis and B. cereus, with IZs values of 0.92 ± 0.2 cm and 0.72 ± 0.05 cm, respectively. Additionally, the crude extract presented antioxidant potential with inhibition percentages of 32.74% ± 0.90 for ABTS and 27.04% ± 1.36 for DPPH. The antimicrobial and antioxidant activities of the crude extract, as well as the antimicrobial property of chitosan-extract films, suggests the potential of these biopolymers for the development of wound healing bandages and new food packaging alternatives.

4.
Int J Biol Macromol ; 271(Pt 1): 132402, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38754662

RESUMO

In this paper, the effects of chitosan film containing star anise essential oil nanofiltration (CFSAO) and superchilled (SC) temperature on the changes of physicochemical and microbiological indexes of rabbit meat patties within 15 days of storage were studied. The total aerobic bacteria counts, malondialdehyde content, protein carbonyl content, total sulfhydryl content, and metmyoglobin content continued to grow throughout the entire experimental period, and the maximum absorption peak at the soret region of myoglobin gradually decreased. Along with the storage time extended, the brightness and redness of rabbit meat significantly decreased (P < 0.05), while the yellowness significantly increased (P < 0.05). The results of storage experiments showed that chitosan composite films and SC temperature had good inhibition on lipid oxidation, myoglobin oxidation and degradation, sulfhydryl content reduction, and microbial growth of rabbit meat after 15 days of storage, and could slow down the change of rabbit meat color.


Assuntos
Quitosana , Embalagem de Alimentos , Armazenamento de Alimentos , Carne , Óleos Voláteis , Animais , Quitosana/química , Quitosana/farmacologia , Coelhos , Embalagem de Alimentos/métodos , Óleos Voláteis/química , Óleos Voláteis/farmacologia , Carne/microbiologia , Armazenamento de Alimentos/métodos , Mioglobina/metabolismo , Mioglobina/química , Conservação de Alimentos/métodos , Qualidade dos Alimentos
5.
Int J Biol Macromol ; 271(Pt 2): 132609, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38788867

RESUMO

Active films based on chitosan incorporated with pine bark extract (PBE) were prepared and characterized. Subsequently, these films were utilized for packaging carp slices in refrigerated storage at 4 ± 1 °C. Analysis of the physicochemical properties and biological activity of the active films revealed that, except for water content, all assessed indices showed an increasing trend with an increase in the amount of supplemental PBE. As this trend progresses, scanning electron microscopy (SEM) analysis revealed deposition on the film surface accompanied by transverse lines and fractures, while the color of the film gradually changed from light yellow to reddish-brown. Fourier transform infrared spectroscopy (FTIR) indicated that the phenolic hydroxyl groups in PBE interacted with the hydrogen in the amino groups of chitosan molecules to form non-covalent bonds. X-ray diffraction analysis (XRD) showed that the reaction between PBE and chitosan altered the crystalline structure of chitosan molecules. Moreover, the analysis of the effects of active films on the pH, water-holding capacity, thiobarbituric acid values, and the total bacterial counts of carp slices revealed that in terms of preservation, films containing 30 % PBE were the most effective, using which the shelf life of carp slices could be extended by 50 %.


Assuntos
Carpas , Quitosana , Embalagem de Alimentos , Pinus , Casca de Planta , Extratos Vegetais , Quitosana/química , Animais , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Casca de Planta/química , Pinus/química , Embalagem de Alimentos/métodos , Espectroscopia de Infravermelho com Transformada de Fourier , Conservação de Alimentos/métodos , Água/química , Concentração de Íons de Hidrogênio
6.
Nano Lett ; 24(22): 6665-6672, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38767991

RESUMO

Shape morphing of biopolymer materials, such as chitosan (CS) films, has great potential for applications in many fields. Traditionally, their responsive behavior has been induced by the differential water swelling through the preparation of multicomponent composites or cross-linking as deformation is not controllable in the absence of these processes. Here, we report an interfacial dehydration strategy to trigger the shape morphing of the monocomponent CS film without cross-linking. The release of water molecules is achieved by spraying the surface with a NaOH solution or organic solvents, which results in the interfacial shrinkage and deformation of the entire film. On the basis of this strategy, a range of CS actuators were developed, such as soft grippers, joint actuators, and a light switch. Combined with the geometry effect, edited deformation was also achieved from the planar CS film. This shape-morphing strategy is expected to enable the application of more biopolymers in a wide range of fields.

7.
Int J Biol Macromol ; 264(Pt 2): 130800, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38548501

RESUMO

The surface morphologies of polymer films have been used to improve the performance or enable new applications of films, such as controllable adhesion, shape morphing and light management. However, complicated and destructive methods were applied to produce surface morphologies on chitosan (CS) film. To overcome this challenge, we report an evaporation-induced self-assembly to form the tunable morphologies on the surface of short-chain chitosan film by varying the evaporation rates that influence the aggregation behavior of polymer chains between order and disorder. It enables the simple, tunable and scalable fabrication of surface morphologies on CS film (CS solution concentration: 2 wt%, drying from room temperature (RT) to 80 °C) that provides controllable haze (3-74 %) and high transmittance (>85 %) for the production of hazy and transparent window coatings. This simple approach to producing tunable surface morphologies could inspire the synthesis of multifunctional polymer films with different surface structures, whose applications can be extended to cell culture interfaces, flexible bioelectronic and optoelectronic devices.


Assuntos
Quitosana , Quitosana/química , Polímeros , Fenômenos Físicos
8.
Regen Biomater ; 11: rbae005, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38414797

RESUMO

For repairing peripheral nerve and spinal cord defects, biomaterial scaffold-based cell-therapy was emerged as an effective strategy, requiring the positive response of seed cells to biomaterial substrate and environment signals. Previous work highlighted that the imposed surface properties of scaffold could provide important guidance cues to adhered cells for polarization. However, the insufficiency of native Schwann cells and unclear cellular response mechanisms remained to be addressed. Given that, this study aimed to illuminate the micropatterned chitosan-film action on the rat skin precursor-derived Schwann cells (SKP-SCs). Chitosan-film with different ridge/groove size was fabricated and applied for the SKP-SCs induction. Results indicated that SKP-SCs cultured on 30 µm size microgroove surface showed better oriented alignment phenotype. Induced SKP-SCs presented similar genic phenotype as repair Schwann cells, increasing expression of c-Jun, neural cell adhesion molecule, and neurotrophic receptor p75. Moreover, SKP-SC-secretome was subjected to cytokine array GS67 assay, data indicated the regulation of paracrine phenotype, a panel of cytokines was verified up-regulated at secreted level and gene expression level in induced SKP-SCs. These up-regulated cytokines exhibit a series of promotive neural regeneration functions, including cell survival, cell migration, cell proliferation, angiogenesis, axon growth, and cellular organization etc. through bioinformatics analysis. Furthermore, the effectively polarized SKP-SCs-sourced secretome, promoted the proliferation and migration capacity of the primarily cultured native rat Schwann cells, and augmented neurites growth of the cultured motoneurons, as well as boosted axonal regrowth of the axotomy-injured motoneurons. Taken together, SKP-SCs obtained pro-neuroregeneration phenotype in adaptive response to the anisotropic topography surface of chitosan-film, displayed the oriented parallel growth, the transition towards repair Schwann cell genic phenotype, and the enhanced paracrine effect on neural regeneration. This study provided novel insights into the potency of anisotropic microtopography surface to Schwann-like cells phenotype regulation, that facilitating to provide promising engineered cell-scaffold in neural injury therapies.

9.
Food Chem ; 444: 138686, 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-38340503

RESUMO

Using novel active food packaging has gradually become a daily necessity in terms of impeding microbial contamination. Here, an antimicrobial photodynamic inactivation (PDI) pH-responsive film is developed by incorporating aloe-emodin (AE) into a vehicle of gelatin/chitosan (GC). Besides enhancement in hydrophobicity, the well-dispersed crystals of AE in the GC matrix by hydrogen bonding can upgrade the film's mechanical strength and barrier. The matrix is capable of regulating the release of AE in response to acidic stimuli by a combination mechanism of diffusion and polymer relaxation. Being benefitted from the inherent bioactivity of AE and the PDI activity under visible light irradiation (i.e., 456 nm), the target film of GC-AE2 has excellent antibacterial effect towards Staphylococcus aureus and Escherichia coli, showing bacterial viability of 9.93 ± 1.33 % and 14.85 ± 1.16 %, respectively. Furthermore, the film can effectively thwart Botrytis cinerea infection in cherry tomatoes, demonstrating its potential in preventing the microbial spoilage of postharvest fruits.


Assuntos
Aloe , Anti-Infecciosos , Quitosana , Emodina , Quitosana/farmacologia , Quitosana/química , Gelatina/química , Anti-Infecciosos/química , Antibacterianos/farmacologia , Antibacterianos/química , Embalagem de Alimentos , Concentração de Íons de Hidrogênio
10.
Int J Biol Macromol ; 259(Pt 1): 129090, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38161019

RESUMO

In this work, a multifunctional preservative film of ZnO/carboxymethyl starch/chitosan (ZnO/CMS/CS) with the unique "Steel Wire Mesh" structure is fabricated by the chemical crosslinked of ZnO NPs, CMS and CS. Unlike traditional nano-filled polymer film, the formation of the "Steel Wire Mesh" structure of ZnO/CMS/CS film is based on the synergistic effect of ZnO NPs filled CMS/CS and the coordination crosslinked between CMS/CS and Zn2+ derived from ZnO NPs. Thanks to the "Steel Wire Mesh" structure, the tensile strength and water vapor barrier of 2.5ZnO/10CMS/CS film are 2.47 and 1.73 times than that of CS film, respectively. Furthermore, the transmittance of 2.5ZnO/10CMS/CS film during antifogging test is close to 89 %, confirming its excellent antifogging effects. And the 2.5ZnO/10CMS/CS film also exhibits excellent long-acting antibacterial activity (up to 202 h), so it can maintain the freshness and appearance of strawberries at least 5 days. More importantly, the 2.5ZnO/10CMS/CS film is sensitive to humidity changes, which achieves real-time humidity monitoring of the fruit storage environment. Note that the preparation method of the film is safe, simple and environmentally friendly, and its excellent degradation performance will not bring any problems of food safety and environmental pollution.


Assuntos
Quitosana , Fragaria , Amido/análogos & derivados , Óxido de Zinco , Quitosana/química , Óxido de Zinco/farmacologia , Óxido de Zinco/química , Antibacterianos/farmacologia , Antibacterianos/química , Embalagem de Alimentos
11.
Food Res Int ; 174(Pt 1): 113580, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37986448

RESUMO

Pineapple-peel-based chitosan film was employed to extend the shelf life of Indian Cottage Cheese, commonly termed "paneer" in the Indian subcontinent. Pineapple peel extracts (PPE) at 3 different concentrations (1-3 %) were incorporated into the chitosan matrix. In comparison to control samples (unpacked paneer), packaged paneer samples exhibited reduced weight loss, lipid peroxidation, and pH changes. The microbiological shelf life of paneer got extended till 9th day at 4 °C when packaged in chitosan-PPE films. Korsmeyer-Peppas's model suggested that the release of polyphenols from the chitosan-PPE film followed Fickian diffusion. As per sensory evaluation on a 9-point hedonic scale, packaged paneer samples were superior in juiciness, texture, color, flavor, and overall acceptability compared to unpackaged paneer samples. As compared to the control sample (CS), the overall acceptance was higher for the film with 1 % pineapple peel extract (CS PPE 1), followed by films with 2 % and 3 % pineapple peel extracts (CS-PPE 2 and CS-PPE 3). The bio-accessibility study utilized the dynamic gastric model to simulate digestion in the upper gastrointestinal tract and revealed 40-60 % recovery rate of polyphenols from the chitosan-pineapple peel film.


Assuntos
Ananas , Queijo , Quitosana , Antioxidantes , Polifenóis , Extratos Vegetais
12.
Polymers (Basel) ; 15(11)2023 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-37299269

RESUMO

Chitosan (CS) films exhibit great potential as a substrate for the in vitro mineralization process. In this study, to mimic the formation of nanohydroxyapatite (HAP) as natural tissue, CS films coated with a porous calcium phosphate were investigated using scanning electron microscopy (SEM), Energy dispersive X-ray spectroscopy (EDX), Fourier transforms infrared spectroscopy (FTIR), X-ray diffractometry (XRD) and X-ray photoelectron spectroscopy (XPS). Calcium phosphate coating deposited on phosphorylated derivatives of CS was obtained by a process based on phosphorylation, Ca(OH)2 treatment and artificial saliva solution (ASS) immersion. The phosphorylated CS films (PCS) were obtained by partial hydrolysis of the PO4 functionalities. It was demonstrated that this precursor phase could induce the growth and the nucleation of the porous calcium phosphate coating when immersed in ASS. Moreover, oriented crystals and qualitative control of calcium phosphate phases on CS matrices are obtained in a biomimetic mode. Furthermore, in vitro antimicrobial activity of PCS was evaluated against three species of oral bacteria and fungi. It revealed an increase in antimicrobial activity with minimum inhibition concentration (MIC) values of 0.10% (Candida albicans), 0.05% (Staphylococcus aureus) and 0.025% (Escherichia coli) which proves their possible use as dental substitute materials.

13.
Int J Mol Sci ; 24(10)2023 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-37239896

RESUMO

In this work, the great performance of chitosan-based films blended with TiO2 (CH/TiO2) is presented to adsorb the hazardous pollutant 2,4-dinitrophenol (DNP) from water. The DNP was successfully removed, with a high adsorption %: CH/TiO2 exhibited a maximum adsorption capacity of 900 mg/g. For pursuing the proposed aim, UV-Vis spectroscopy was considered a powerful tool for monitoring the presence of DNP in purposely contaminated water. Swelling measurements were employed to infer more information about the interactions between chitosan and DNP, demonstrating the presence of electrostatic forces, deeply investigated by performing adsorption measurements by changing DNP solutions' ionic strength and pH values. The thermodynamics, adsorption isotherms, and kinetics were also studied, suggesting the DNP adsorption's heterogeneous character onto chitosan films. The applicability of pseudo-first- and pseudo-second-order kinetic equations confirmed the finding, further detailed by the Weber-Morris model. Finally, the adsorbent regeneration was exploited, and the possibility of inducing DNP desorption was investigated. For this purpose, suitable experiments were conducted using a saline solution that induced the DNP release, favoring the adsorbent reuse. In particular, 10 adsorption/desorption cycles were performed, evidencing the great ability of this material that does not lose its efficiency. As an alternative approach, the pollutant photodegradation by using Advanced Oxidation Processes, allowed by the presence of TiO2, was preliminary investigated, opening a novel horizon in the use of chitosan-based materials for environmental applications.


Assuntos
Quitosana , Poluentes Ambientais , Poluentes Químicos da Água , 2,4-Dinitrofenol , Água , Quitosana/química , Adsorção , Termodinâmica , Cinética , Poluentes Químicos da Água/química , Concentração de Íons de Hidrogênio
14.
Polymers (Basel) ; 15(10)2023 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-37242810

RESUMO

A recent focus on the development of biobased polymer packaging films has come about in response to the environmental hazards caused by petroleum-based, nonbiodegradable packaging materials. Among biopolymers, chitosan is one of the most popular due to its biocompatibility, biodegradability, antibacterial properties, and ease of use. Due to its ability to inhibit gram-negative and gram-positive bacteria, yeast, and foodborne filamentous fungi, chitosan is a suitable biopolymer for developing food packaging. However, more than the chitosan is required for active packaging. In this review, we summarize chitosan composites which show active packaging and improves food storage condition and extends its shelf life. Active compounds such as essential oils and phenolic compounds with chitosan are reviewed. Moreover, composites with polysaccharides and various nanoparticles are also summarized. This review provides valuable information for selecting a composite that enhances shelf life and other functional qualities when embedding chitosan. Furthermore, this report will provide directions for the development of novel biodegradable food packaging materials.

15.
Int J Biol Macromol ; 242(Pt 3): 124951, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37211071

RESUMO

Neutralization treatment improved the slow-release antioxidant food packaging function of chitosan (CS)/bamboo leaf flavone (BLF)/nano-metal oxides composite films. The film cast from the CS composite solution neutralized by KOH solution had good thermal stability. The elongation at break of the neutralized CS/BLF film was increased by about 5 times, which provided the possibility for its packaging application. After 24 h of soaking in different pH solutions, the unneutralized films swelled severely and even dissolved, while the neutralized films maintained the basic structure with a small degree of swelling, and the release trend of BLF conformed to the logistic function (R2 ≥ 0.9186). The films had a good ability to resist free radicals, which was related to the release amount of BLF and the pH of the solution. The antimicrobial neutralized CS/BLF/nano-ZnO film, like the nano-CuO and Fe3O4 films, were effective in inhibiting the increase in peroxide value and 2-thiobarbituric acid induced by thermal oxygen oxidation of rapeseed oil and had no toxicity to normal human gastric epithelial cells. Therefore, the neutralized CS/BLF/nano-ZnO film is likely to become an active food packaging material for oil-packed food, which can prolong the shelf life of packaged food.


Assuntos
Quitosana , Humanos , Quitosana/farmacologia , Quitosana/química , Antioxidantes/farmacologia , Antioxidantes/química , Óleo de Brassica napus , Flavonoides , Embalagem de Alimentos , Óxidos/farmacologia
16.
J Food Sci ; 88(6): 2571-2582, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37212525

RESUMO

In this study, the bark of the Aquilaria agallocha was extracted, and the phenolic content of A. agallocha extract was determined using high-performance liquid chromatography-diode array detector. The A. agallocha extract-chitosan edible films were prepared by using a different amount of A. agallocha extract (0, 1, 4, and 8 mL) and chitosan solution. Some physical properties of A. agallocha extract-chitosan edible films, water vapor permeability, solubility, swelling ratio, humidity ratio, thickness, scanning electron microscopy, and Fourier transform infrared spectroscopy analysis were investigated. The antibacterial activities, total phenolic content, and antioxidant capacity analysis of the A. agallocha extract-chitosan edible films were performed. The total phenolic content (0, 1, 4, and 8 mL of A. agallocha extract-chitosan edible films 0.92 ± 0.09, 1.34 ± 0.04, 2.94 ± 0.10, and 4.62 ± 0.10 mg gallic acid equivalent (GAE)/g film, respectively) and antioxidant capacity (0, 1, 4, and 8 mL of A. agallocha extract-chitosan edible films 52.61 ± 2.85, 104.28 ± 4.78, 304.30 ± 18.23, and 592.11 ± 0.67 mg Trolox equivalent (TE)/g film, respectively) of A. agallocha extract-chitosan edible films increased with the increase in the amount of extract. At the same time, the increase in the amount of antioxidant capacity improved the physical features of the films. The results of the antibacterial activity studies showed that all of the A. agallocha extract-chitosan edible films prevented bacterial growth from Escherichia coli and Staphylococcus aureus considering controlling group. PRACTICAL APPLICATIONS: To investigate the activity of antioxidant extract-biodegradable film, the A. agallocha extract-chitosan edible film had prepared. The results showed that A. agallocha extract-chitosan edible film was antioxidant and antibacterial properties and was used as food packaging material successfully.


Assuntos
Antioxidantes , Quitosana , Antioxidantes/farmacologia , Antioxidantes/química , Quitosana/química , Antibacterianos/farmacologia , Antibacterianos/química , Permeabilidade , Embalagem de Alimentos/métodos , Fenóis
17.
Carbohydr Polym ; 311: 120784, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37028863

RESUMO

The increased demand for food quality and safety has led the food industry to pay urgent attention to new packaging materials with antimicrobial activity. In this study, we combined photodynamic inactivation of bactericidal technology in food packaging materials by incorporating fluorescent carbon quantum dots (CDs) prepared from the natural plant turmeric into a chitosan matrix to prepare a series of active composite food packaging films (CDs-CS). The chitosan film containing CDs had better mechanical properties, UV protection and hydrophobicity. Under irradiation with a 405 nm light source, the composite film was able to produce abundant reactive oxygen species, and the CDs-CS2 film exhibited reductions of approximately 3.19 and 2.05 Log10 CFU/mL for Staphylococcus aureus and Escherichia coli respectively within 40 min. In cold pork storage applications, CDs-CS2 films showed inhibition of the growth of colonization in pork and retarded the spoilage of pork within 10 days. This work will provide new insights to explore safe and efficient antimicrobial food packaging.


Assuntos
Anti-Infecciosos , Quitosana , Nanocompostos , Pontos Quânticos , Embalagem de Alimentos , Quitosana/farmacologia , Curcuma , Carbono , Antibacterianos/farmacologia , Anti-Infecciosos/farmacologia , Tecnologia
18.
Materials (Basel) ; 16(3)2023 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-36769933

RESUMO

Chitosan is a biopolymer with great potential as food packaging due to its ability to create a film without additives and its better mechanical and antibacterial qualities compared to other biopolymers. However, chitosan film still has limitations due to its high moisture sensitivity and limited flexibility. Incorporating ZnO nanoparticles (ZnO-NPs) and stearic acid (SA) into chitosan films was expected to improve tensile strength, water vapor barrier, and antibacterial capabilities. This study aims to find the optimal formula for biohybrid nanocomposite films composed of chitosan, ZnO-NPs, and SA. The full factorial design approach-4 × 2 with 3 replicates, i.e., two independent variables, namely %ZnO-NPs at 4 levels (0%, 0.5%, 1%, and 3%, w/w) and %SA at 2 levels (0% and 5%, w/w)-was utilized to optimize chitosan-based biohybrid nanocomposite films, with the primary interests being antibacterial activities, water vapor barrier, and tensile strength. The incorporation of ZnO-NPs into chitosan films could increase antibacterial activity, while SA decreased it. The addition of SA had a good effect only in decreasing water vapor transmission rate (WVTR) values but a detrimental effect on other film properties mentioned above. The incorporation of ZnO-NPs enhanced all functional packaging properties of interest. The suggested solution of the optimization study has been validated. As a result, the formula with the inclusion of 1% ZnO-NPs without SA is optimal for the fabrication of active antibacterial films with excellent multifunctional packaging capabilities.

19.
Int J Biol Macromol ; 231: 123293, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36652982

RESUMO

The aim of this study was to prepare superhydrophobic chitosan films using a ZnO nanoparticle coating and stearic acid hydrophobic modification. A 1 % concentration of ZnO nanoparticles and a 1 % concentration of stearic acid generated a superhydrophobic film with the largest contact angle (WCA) of 156°, which was attributed to the synergy of micro/nano-level hierarchical structure and low surface energy modification. The superhydrophobic film showed better stability to acid, alkali, heat, and UV irradiation than a neat chitosan film and a reduction in light transmittance of 14.4 % at 354 nm. The superhydrophobic chitosan film also showed excellent self-cleaning and oil-water separation performance. Our findings will expand the application of chitosan films in food packaging, outdoor self-cleaning materials and oil-water separations.


Assuntos
Quitosana , Óxido de Zinco , Quitosana/química , Óxido de Zinco/química , Interações Hidrofóbicas e Hidrofílicas , Água/química
20.
Int J Biol Macromol ; 233: 123430, 2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-36716844

RESUMO

The problem of environmental plastic contamination is one of the most serious issues facing our world today. The majority of the packaging materials used to preserve food are made of plastic which is considered an environmental issue. Natural kaolinite clay (KC) and Ficus leaf extract (FLE) were combined with chitosan in this work to create a novel antioxidant and biodegradable food packaging film. Chitosan/KC/FLE film was compared to chitosan film, Chitosan/KC, and Chitosan/FLE films in terms of structural, physical, and functional aspects. The addition of FLE and/or KC significantly improved the light and moisture barrier characteristics, mechanical properties, and antioxidant capabilities of chitosan film. Moreover, KC addition had a remarkable impact on the water vapor permeability and the biodegradability of the chitosan film. Because of the synergistic action of FLE and KC, the Chitosan/KC/FLE film delivered strong barrier and antioxidant capabilities. Furthermore, Chitosan/KC/FLE film was tested as packaging material on fresh-cut apple slices and demonstrated good food preservation regarding the weight loss, browning index, and total phenolic content of the fruit. According to our findings, Chitosan/KC/FLE film might be employed as a possible food packaging material in the food industry.


Assuntos
Carica , Quitosana , Ficus , Malus , Quitosana/química , Malus/química , Antioxidantes/farmacologia , Antioxidantes/química , Embalagem de Alimentos , Argila , Caulim , Plásticos , Extratos Vegetais/química
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