Antimicrobial Activity Of Chitosan Research Articles

Antimicrobial activity of chitosan- edible films containing a combination of carvacrol and rosemary nano-emulsion against Salmonella enterica serovar Typhimurium and Listeria monocytogenes for ground meat

This research aimed to assess the potential of active food packaging as an innovative approach to enhance the quality of fresh food products. Specifically, our focus was on developing chitosan edible films combined with rosemary nanoemulsion (Ch-RNE) and carvacrol nano-emulsion (Ch-CNE) as effective antibacterial food packaging solutions. The efficacy of these films against artificially inoculated L. monocytogenes (NCTC 13372\\ ATCC® 7644) as a Gram-positive bacterium, and S. enterica serovar Typhimurium (ATCC 14028) as a Gram-negative bacterium, in ground meat was investigated. The size of the prepared nano-emulsions was characterized using zeta sizer, FTIR and HRTEM. The MIC of both nano-emulsions against both pathogens was found to be 0.78 % and 1.56 %. Filmogenic mixtures were casted using these concentrations, which were then dried and evaluated for their physical and mechanical properties.

An insight into the effect of interaction with protein on antibacterial activity of chitosan derivatives

Antimicrobial activity of chitosan in protein-rich media is of a particular interest for various protein-based drug delivery and other systems. For the first time, bacteriostatic activity of chitosan derivatives in the presence of caseinate sodium (CAS) was studied and discussed. Complexation of chitosan derivatives soluble in acidic (CH and RCH) or alkalescent (RCH) media with CAS was confirmed by fluorescent spectroscopy, turbodimetry, light scattering data and measurement of electrical potentials of CAS/chitosan derivative complexes. An addition of CH and RCH caused a static quenching of CAS. Binding constants Kb determined for CH/CAS and RCH/CAS complexes at pH 6.0 were equal to 29.8 × 106 M−1 and 8.9 × 106 M−1, respectively. Kb value of RCH/CAS complex at pH 7.4 was equal to 1.1 × 105′M−1. The poisoned food method was used for counting the number and the direct measurement of the size of bacterial colonies on the surfaces of turbid agar media containing CAS/chitosan derivative complexex. Complete suppression of E. coli cells growth and restriction of S. aureus cells growth were observed on the surface of acidic media. A high concentration of CAS reduced the activity. The activity of RCH in alkalescent media is low or absent. These results can be promising for preparation of microbiologically stable protein-based drug delivery systems.

Chitosan-photocatalyst nanocomposite on polyethylene films as antimicrobial coating for food packaging

Chitosan (CS), an edible and non-toxic natural biopolymer, has been widely used in food preservation attributed to its intrinsic antimicrobial, biodegradable, and excellent film-forming properties. In this work, we report photocatalyst-loaded chitosan coating on commercial polyethylene (PE) film with enhanced antimicrobial properties for food packaging application. To improve the chemical stability of zinc oxide (ZnO) photocatalyst in acidic chitosan matrix, a thin layer (1–5 nm) of amorphous tin oxide (SnOx) was coated on ZnO nanoparticles. Consequently, the charge transfer efficiency of ZnO is improved and most of the surface defects are retained according to the studies of UV–Vis and fluorescence spectroscopy. The thin SnOx coating on ZnO was observed by high-resolution transmission electron microscopy (HRTEM) and its effects on crystallinity and particle size of ZnO were examined using X-ray diffraction (XRD) and particle sizer, respectively. The addition of ZnO@SnOx particles in chitosan coating increases water contact angle (WCA) and enhances thermal stability of chitosan coating. The antimicrobial activity of chitosan, ZnO-SnOx nanoparticles, and CS-ZnO@SnOx coated PE films were examined against both Gram-negative (E. coli, A. faecalis) and Gram-positive (S. aureus, B. subtilis) bacteria. Compared to the limited antimicrobial effects of chitosan, ZnO-SnOx demonstrates an improved inhibition effect on bacterial growth over 48 h period under light. For the CS-ZnO@SnOx nanocomposite coated PE films, no inhibition zone was observed due to the limitation of disc diffusion method. Meanwhile, there were no bacterial colonies found to develop on the film, rendering this CS nanocomposite coating a good candidate for food packaging applications.

Characterization of Synthetic Polymer Coated with Biopolymer Layer with Natural Orange Peel Extract Aimed for Food Packaging.

This research was aimed to make biolayer coatings enriched with orange peel essential oil (OPEO) on synthetic laminate, oriented poly(ethylene-terephthalate)/polypropylene (PET-O/PP). Coating materials were taken from biobased and renewable waste sources, and the developed formulation was targeted for food packaging. The developed materials were characterized for their barrier (O2, CO2, and water vapour), optical (colour, opacity), surface (inventory of peaks by FTIR), and antimicrobial activity. Furthermore, the overall migration from a base layer (PET-O/PP) in an acetic acid (3% HAc) and ethanol aqueous solution (20% EtOH) were measured. The antimicrobial activity of chitosan (Chi)-coated films was assessed against Escherichia coli. Permeation of the uncoated samples (base layer, PET-O/PP) increased with the temperature increase (from 20 °C to 40 °C and 60 °C). Films with Chi-coatings were a better barrier to gases than the control (PET-O/PP) measured at 20 °C. The addition of 1% (w/v) OPEO to the Chi-coating layer showed a permeance decrease of 67% for CO2 and 48% for O2. The overall migrations from PET-O/PP in 3% HAc and 20% EtOH were 1.8 and 2.3 mg/dm2, respectively. Analysis of spectral bands did not indicate any surface structural changes after exposure to food simulants. Water vapour transmission rate values were increased for Chi-coated samples compared to the control. The total colour difference showed a slight colour change for all coated samples (ΔE > 2). No significant changes in light transmission at 600 nm for samples containing 1% and 2% OLEO were observed. The addition of 4% (w/v) OPEO was not enough to obtain a bacteriostatic effect, so future research is needed.

Aplication Chitosan Modified Carboxymethyl as Antibacterial Agent of Paper Packaging

Chitosan and chitosan modified carboxymethyl were used to enhance performances of paper packaging. Chitosan 1.0 wt% and chitosan modified carboxymethyl solutions with concentrations of 0.25; 0.5 and 1.0 wt% were manually applied on paper surface using dip coating method. Effects of chitosan coatings on antibacterial properties of the paper were investigated. The antimicrobial activity of chitosan against gram-positive (Staphylococcus aureus) and gram-negative bacteria (Escherichia coli) was found to be enhanced when chitosan and chitosan modified carboxymethyl solution were entrapped within paper. Further paper coated chitosan and chitosan modified carboxymethyl has higher antibacterial activity againt S. aureus rather than E. coli.
 Keywords: Chitosan carboxymethyl, antibacterial agent, paper packaging

The Effects of Chitosan on the Healing Process of Oral Mucosa: An Observational Cohort Feasibility Split-Mouth Study

The healing process is a dynamic process accompanied by some classical symptoms of inflammation such as redness, swelling, pain, and loss of function. Chitosan is a natural polymer with properties that contribute to tissue healing, with properties that could be applied in periodontal therapy, such as the wound healing of oral mucosa. This experimental split-mouth study aims to assess the possibilities of chitosan influencing the healing process of oral mucosa in eight patients, where the studied group was subjected to two oral surgeries: one with chitosan hydrogel into the socket and other without the biomaterial. A semi-quantitative analysis of the data was performed. Some classic signs of inflammation in a short period of time were observed where chitosan acted, compared to the control. An absence of bleeding was observed in the chitosan cases. According to the literature, chitosan recruits and activates neutrophils and macrophages and stimulates angiogenesis. Hemostatic and antimicrobial activity of chitosan also play an important role in wound healing. Chitosan seems to improve the postoperative quality of patients, allowing rapid wound healing with less complications.

Preparation of l-Arginine Schiff Bases Modified Chitosan Derivatives and Their Antimicrobial and Antioxidant Properties.

We successfully prepared a series of l-arginine Schiff bases acylated chitosan derivatives, aiming to improve the antioxidant activity and antimicrobial activity of chitosan by introducing a furan ring, pyridine ring, and l-arginine structure. The accuracy of the structures of ten compounds was characterized by FT-IR and 1H NMR. In terms of DPPH radical scavenging activity, except for compound CR3PCA, the scavenging rate of other compounds was higher than chitosan, especially CRCF and CRBF had strong scavenging abilities. At the same time, in the superoxide-radical scavenging activity assay, CRCF, CRBF, CR3PCA, CR2C3PCA, and CR2B3PCA were comparable to positive control at 1.60 mg/mL. Simultaneously, CRFF, CRCF, and CRBF had a certain inhibitory effect on Botrytis cinerea. Furthermore, the inhibitory effect of CRFF, CRCF, and CR3PCA on Staphylococcus aureus was very well, close to the positive control at 1.00 mg/mL. CRCF and CR2B3PCA showed better inhibitory effects on Escherichia coli than other compounds. The MTT assay was used to determine the cytotoxicity of the chitosan derivatives, which proved their safety to fibroblast cells. In summary, the study indicated that some of these compounds have the potential for further development and utilization in the preparation of antioxidants and antimicrobial agents.

ANTIOXIDANT AND ANTIMICROBIAL ACTIVITY OF CUTTLEBONE CHITOSAN AGAINST Escherichia coli, Staphylococcus aureus AND Candida albicans

The discovery of new antibiotics for infectious diseases has become challenging due to the rise of antimicrobial resistance.Meanwhile, chitosan has been considerably used in many branches of research. It has been discovered to have some good benefitsin medicals, pharmaceuticals, and food technologies. In this study, chitosan was prepared from the cuttlebone of Sepia sp. bychemical method and analyzed by using FT-IR spectrophotometer for the confirmed presence of its functional groups. Thereare three types of reactive functional groups in the chitosan which are the amino group and primary and secondary hydroxylgroup attached to the C-2, C-3, and C-6 positions respectively. Chitosan has a high cationic property due to the presence of itsamino group. The bacteriostatic activity of chitosan occurs due to its positive charge in acidic concentration that interacts withthe negatively charged residue of carbohydrates, lipids, and proteins located on the cell surface of bacteria. The antioxidantactivity was conducted using DPPH radical scavenging assay with a chitosan concentration ranging from 0.1 to 10 mg/mL anda hydrogen peroxide scavenging assay with a chitosan concentration ranging from 0.1 to 1.6 mg/mL. The antimicrobial activityof chitosan from cuttlebone was analyzed against two different bacterial strains (Escherichia coli & Staphylococcus aureus)and a fungal strain, Candida albicans by disc diffusion and minimum inhibitory concentration (MIC) method. The results showthat through the DPPH radical assay, the scavenging activity was 59.7% at the concentration of chitosan at 10mg/mL, whilethrough the hydrogen peroxide assay the scavenging activity was 56% at the concentration of chitosan at 1.6 mg/mL. Besides,this chitosan from Sepia sp. has concentration-dependent antimicrobial activity with higher antifungal activity compared toantibacterial activity against all tested organisms and may become a potential agent for antibiotic discovery

Fermentative production, characterization and antimicrobial activity of chitosan from some Zygomycetes fungi

Fermentative production, characterization and antimicrobial activity of chitosan from some Zygomycetes fungi

Synthesis, characterization and application of chitosan conjugated heterocyclic compounds

Derivatives of formyl pyrazole were synthesized by the reaction of acetophenone, 4-methyl acetophenone, 3-acetyl furan, 3-acetyl thiophen and phenyl hydrazine derivatives. The product was treated with Vilsmeier reagent producing different formyl pyrazole derivatives which were characterized by FT-IR, 1HNMR, Elemental analysis and Mass spectroscopy. The formyl pyrazole derivatives were reacted with chitosan to produce chitosan/ pyrazole Schiff base. These Schiff bases were characterized by FT-IR and TGA.The antimicrobial activity of chitosan/ pyrazol Schiff base (CSB) was evaluated against Gram-positive bacteria (Staphylococcus aureus and Bacillus cereus), gram negative bacterium (Escherichia coli) and fungus (Aspergillus niger). Results indicated agood inhibitory activity for CSB-14 when tested against B.cereus that gave inhibition zone of 7.5 ± 0.6 (mm), however CSB-18 gave a pronounced inhibitory activity against S. aureus and recorded 25 ± 2.0 (mm). All synthesized derivatives have no inhibitory activity against Gram negative E. coli. CSB-14, and CSB-15 exhibited inhibitory activity against tested A. niger that was used as a fungal model which gave 19 ± 0.9 and 18 ± 1.0 inhibition zone (mm) respectively. Thus, these results showed that, functionalization of chitosan with the hetero-cyclic compounds created biological activities of the synthesized derivatives; hence the synthesized pyrazole derivatives have not recorded any inhibitory activity before its immobilization onto chitosan.

ATIVIDADE ANTIMICROBIANA DE QUITOSANAS E SEUS DERIVADOS: INFLUÊNCIA DAS CARACTERÍSTICAS ESTRUTURAIS

ANTIMICROBIAL ACTIVITY OF CHITOSAN AND ITS DERIVATIVES: INFLUENCE OF ITS STRUCTURAL CHARACTERISTICS. In recent years, there has been an increasing interest in the development of antimicrobial materials for different applications, especially in the biomedical field. In this context, chitosan is one of the most employed materials due to its highly attractive properties, such as biocompatibility, biodegradability, non-toxicity, and antimicrobial activity against gram-negative and gram-positive bacteria and fungi. In this review, we discuss the different methods used to obtain chitosan and point out how they affect the structural and chemical properties of this material, followed by a detailed discussion on how these properties influence its antimicrobial activities. Additionally, we summarize the most accepted antimicrobial mechanisms of action for chitosans. Specifically, we aim to provide a comprehensive overview on the last findings and progress reported in the literature on the factors that influence the antimicrobial activity of chitosan, e.g., polymeric average molecular weight (MV ), average degree of acetylation (DA), water-soluble derivatization and sample degree of purity. The data available in the literature indicate that in addition to the structural properties, the effectiveness of such antimicrobial activity of chitosan is also dependent on the target microorganisms. This review will help researchers to better understand the mechanism of action of chitosan against microorganisms based on its structural characteristics.

Bioactive pectic polysaccharides from bay tree pruning waste: Sequential subcritical water extraction and application in active food packaging

The potential isolation of bio-active polysaccharides from bay tree pruning waste was studied using sequential subcritical water extraction using different time-temperature combinations. The extracted polysaccharides were highly enriched in pectins while preserving their high molecular mass (10–100 kDa), presenting ideal properties for its application as additive in food packaging. Pectin-enriched chitosan films were prepared, improving the optical properties (≥95% UV-light barrier capacity), antioxidant capacity (˃95% radical scavenging activity) and water vapor permeability (≤14 g·Pa−1·s−1·m−1·10−7) in comparison with neat chitosan-based films. Furthermore, the antimicrobial activity of chitosan was maintained in the hybrid films. Addition of 10% of pectins improved mechanical properties, increasing the Young's modulus 12%, and the stress resistance in 51%. The application of pectin-rich fractions from bay tree pruning waste as an additive in active food packaging applications, with triple action as antioxidant, barrier, and antimicrobial has been demonstrated.

The Effect of Molecular Weight on the Antimicrobial Activity of Chitosan from Loligo opalescens for Food Packaging Applications.

The growing requirement for sustainable processes has boosted the development of biodegradable plastic-based materials incorporating bioactive compounds obtained from waste, adding value to these products. Chitosan (Ch) is a biopolymer that can be obtained by deacetylation of chitin (found abundantly in waste from the fishery industry) and has valuable properties such as biocompatibility, biodegradability, antimicrobial activity, and easy film-forming ability. This study aimed to produce and characterize poly(lactic acid) (PLA) surfaces coated with β-chitosan and β-chitooligosaccharides from a Loligo opalescens pen with different molecular weights for application in the food industry. The PLA films with native and depolymerized Ch were functionalized through plasma oxygen treatment followed by dip-coating, and their physicochemical properties were assessed by Fourier-transform infrared spectroscopy, X-ray diffraction, water contact angle, and scanning electron microscopy. Their antimicrobial properties were assessed against Escherichia coli and Pseudomonas putida, where Ch-based surfaces reduced the number of biofilm viable, viable but nonculturable, and culturable cells by up to 73%, 74%, and 87%, respectively, compared to PLA. Biofilm growth inhibition was confirmed by confocal laser scanning microscopy. Results suggest that Ch films of higher molecular weight had higher antibiofilm activity under the food storage conditions mimicked in this work, contributing simultaneously to the reuse of marine waste.

Molecular features of the interaction and antimicrobial activity of chitosan in a solution containing sodium dodecyl sulfate

Molecular interaction of chitosan with sodium dodecyl sulfate (SDS) is a more complicated process than it has been imagined so far. For the first time it has been shown that the shorter chitosan chains are, the more preferably they interact with the SDS and the larger-in-size microparticles they form. The influence of ionic strength, urea and temperature on microparticles formation allows interpreting the mechanism of microparticles formation as a cooperative electrostatic interaction between SDS and chitosan with simultaneous decrease in the surface charge of the complexes initiating the aggregation of microparticles. It is shown that hydrogen bonding is mainly responsible for the aggregation while hydrophobic interaction has a lesser effect. Chitosan demonstrates a high bacteriostatic activity in the presence of SDS in solution and can be promising for preparation of microbiologically stable pharmaceutical hydrocolloids, cosmetic products and chitosan-based Pickering emulsions containing strong anionic surfactants.

Preparation and Antimicrobial Activity of Chitosan and Its Derivatives: A Concise Review.

Despite the advantages presented by synthetic polymers such as strength and durability, the lack of biodegradability associated with the persistence in the environment for a long time turned the attention of researchers to natural polymers. Being biodegradable, biopolymers proved to be extremely beneficial to the environment. At present, they represent an important class of materials with applications in all economic sectors, but also in medicine. They find applications as absorbers, cosmetics, controlled drug delivery, tissue engineering, etc. Chitosan is one of the natural polymers which raised a strong interest for researchers due to some exceptional properties such as biodegradability, biocompatibility, nontoxicity, non-antigenicity, low-cost and numerous pharmacological properties as antimicrobial, antitumor, antioxidant, antidiabetic, immunoenhancing. In addition to this, the free amino and hydroxyl groups make it susceptible to a series of structural modulations, obtaining some derivatives with different biomedical applications. This review approaches the physico-chemical and pharmacological properties of chitosan and its derivatives, focusing on the antimicrobial potential including mechanism of action, factors that influence the antimicrobial activity and the activity against resistant strains, topics of great interest in the context of the concern raised by the available therapeutic options for infections, especially with resistant strains.

Дослідження антимікробної дії хітозану та біологічно активних композицій на його основі

Due to the large number of functional groups in chitosan is provide the possibility of formation bonds with chemical compounds, which allows you to create polymeric complexes with new physicochemical properties and biological activity. Therefore, chitosan is widely used as a biopolymeric carrier of degradable preparation of different orientation, which ensures their effective and prolonged action. Compositions of chitosan with natural biopreservatives, which allow to obtain promising plant protection products and agricultural products, deserve special attention. Recent developments, as well as the need for safe, practical and effective food preservatives have aroused increased interest in substances such as sorbate and its combined use with chitosan. In recent decades, sorbate and chitosan have been tested and widely used in the storage of various foods around the world. The issues of adaptogenic action, antimicrobial activity of chitosan in combination with biologically active components remain little studied in Ukraine. Given the global trend towards a gradual transition to organic production, the study of the mechanisms of action of chitosan and its compounds with organic acids is a promising area of research in the control of pathogenic microorganisms for storage of fruits and vegetables. The aim of the study was to study the effectiveness of the integrated use of chitosan with sorbic acid against phytopathogenic microorganisms. The research used methods generally accepted in microbiology and phytopathology. Specificity of antimicrobial activity and prolongation of action of chitosan, sorbic acid and their mixture with respect to different isolates and strains of phytopathogenic microorganisms has been established. The bacteriostatic effect of a mixture of chitosan and sorbic acid in the variant with bacterial isolates, which was observed during 5 days was investigated. The composition of chitosan and sorbic acid contributed to the inhibition of mycelial growth of isolates of pathogens of the genera Fusarium and Alternaria.

Antibacterial Activity of Chitosan, Some Plant Seed Extracts and Oils Against Pathogenic Organisms Escherichia coli and Staphylococcus aureus

In this present study, various concentrations (0.5, 1, and 2%) of chitosan extracted through the chemical methods from the shells of crayfish (Astacus leptodactylus), pink shrimp (Parapenaeus longirostris), blue crab (Callinectes sapidus) shells, aqueous extracts of black cumin (Nigella sativa L), flaxseed (Linum usitatissimum), Chaste Tree (Vitex agnus-castus L.) and black cumin and flaxseed oil were tested in vitro for their antibacterial activities against tow pathogenic bacteria Escherichia coli and Staphylococcus aureus, using the disk diffusion method. On the other hand, were Eritromisin and florfenicol were used as a positive control. The negative control was Acetic Acid and cotton oil. Antimicrobial activity of chitosan is affected by different intrinsic and extrinsic factors. chitosan Source, molecular weight, deacetylation degree, viscosity, and solvent material, pH, ionic strength, metal ions, and bacteria cultures. In the present study, all four extracted chitosans were showed different antimicrobial effects on two different types of bacteria, while there are not any antibacterial effect of aqueous extracts and oils of the three plants seeds that used in this study.

Antimicrobial activity of chitosan in combination with silver diamine fluoride against streptococcus mutans - An in-vitro study

Silver diamine fluoride (SDF) is a recently introduced caries arresting agent. Some of its side effects include staining of teeth and cytotoxicity. Chitosan has an anti-cariogenic and plaque-reducing effect. Thus, considering the side-effects of SDF and the antibacterial efficacy of chitosan, the present study was done to evaluate the antibacterial effectiveness of SDF and chitosan in combination against Streptococcus mutans.60 sterile Petri dishes were sub-divided into five groups of 12 Petri dishes each: Group 1: 38% SDF, Group 2: 2% chitosan, Group 3: 3% chitosan, Group 4: 38% SDF + 2% chitosan, Group 5: 38% SDF + 3% chitosan. Three different volumes: 30 µl,60 µl,90 µl were used. The agar well diffusion method was used to evaluate the antibacterial activity. The highest zone of inhibition was found in Group 1: 38% SDF at 90 µl and the lowest was found in group 3: Chitosan 3% at 30 µl. Group 1- 38% SDF showed higher antibacterial activity amongst all the other four groups under study. And a comparable antibacterial effect between group 1: 38% SDF at 30 µl and Group 5: 3% chitosan and 38% SDF at 30 µl.SDF at 38% showed higher antibacterial activity against S.mutans and a comparable antibacterial effect between group 1: 38% SDF at 30 µl and Group 5: 3% chitosan and 38% SDF at 30 µl. Thus, considering the side effects of SDF, further studies are required in this aspect to test the cytotoxicity of SDF and chitosan in combination.

Efficiency of chitosan synergism with clove essential oil in the coating of intentionally contaminated Tambaqui fillets

The edible coating of chitosan with clove essential oil (CEO) was studied for its ability to reduce the microbial growth of pathogens (Escherichia coli O157:H7 CDCEDL933, Listeria monocytogenes CERELA, Salmonella Enteritidis ATCC13076, Staphylococcus aureus ATCC43300, and Pseudomonas aeruginosa ATCC27853) in Tambaqui fillets kept under refrigeration. In in vitro tests, chitosan showed higher antimicrobial activity against S. aureus and L. monocytogenes (MIC 0.5%), and CEO for L. monocytogenes (MIC 0.08%). Based on the antimicrobial activity of chitosan and CEO, Tambaqui fillets were subjected to different treatments, T1: chitosan 2%; T2: chitosan 2% + CEO 0.16%, and T3: chitosan 0.5% + CEO 0.08%, kept at 4 ºC for 72 h. The chitosan coating, incorporated with CEO, inhibited microorganisms in Tambaqui fillets and enhanced coating efficiency (p < 0.05). It was most effective against L. monocytogenes and S. aureus at the lowest CEO concentration (0.08%). Chitosan coating in combination with CEO enhanced the antimicrobial effect of pathogens on Tambaqui fillets, increased their shelf life under refrigeration, and was more effective against Gram-positive pathogens than Gram-negative pathogens.

Investigation of the structural, physical properties, antioxidant, and antimicrobial activity of chitosan- nano-silicon aerogel composite edible films incorporated with okara powder

The chitosan/okra powder/nano-silicon aerogel composite films were prepared by casting method and their physicochemical properties and structural characterization were studied. The results showed that the composite film had good mechanical properties, barrier properties and optical properties. The composite film has strong flexibility. The surface glossiness of C/D/S1.5:1:0.1 film was 14.4Gu. As for the antibacterial activity, all the composite films had strong antibacterial activity against Gram-negative (E. coli) and Gram-positive (S. aureus), and the inhibition zone of C/D/S1.5:1:0.10 against E. coli reached 551.96 mm2, the inhibition zone for S. aureus was 350.29 mm2. The composite film had uniform, non-porous, continuous and dense surface characteristics. The structural characterization confirmed that there was good compatibility between chitosan, okara powder and nano-silicon aerogel. In summary, the composite films had excellent performance and structure, which promoted the research of functional packaging films.