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1.
Materials (Basel) ; 17(15)2024 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-39124333

RESUMO

Waste from non-degradable packaging materials poses a serious environmental risk and has led to interest in developing sustainable bio-based packaging materials. Sustainable packaging materials have been made from diverse naturally derived materials such as bamboo, sugarcane, and corn starch. In this study, we made a sustainable packaging film using chitosan extracted from the biomass of yellow mealworm (Tenebrio molitor) shell waste. The extracted chitosan was used to create films, cross-linked with citric acid (CA) and with the addition of glycerol to impart flexibility, using the solvent casting method. The successful cross-linking was evaluated using Fourier-Transform Infrared (FTIR) analysis. The CA cross-linked mealworm chitosan (CAMC) films exhibited improved water resistance with moisture content reduced from 19.9 to 14.5%. Improved barrier properties were also noted, with a 28.7% and 10.2% decrease in vapor permeability and vapor transmission rate, respectively. Bananas were selected for food preservation, and significant changes were observed over a duration of 10 days. Compared to the control sample, bananas packaged in CAMC pouches exhibited a lesser loss in weight because of excellent barrier properties against water vapor. Moreover, the quality and texture of bananas packaged in CAMC pouch remained intact over the duration of the experiment. This indicates that adding citric acid and glycerol to the chitosan structure holds promise for effective food wrapping and contributes to the enhancement of banana shelf life. Through this study, we concluded that chitosan film derived from mealworm biomass has potential as a valuable resource for sustainable packaging solutions, promoting the adoption of environmentally friendly practices in the food industry.

2.
Artigo em Inglês | MEDLINE | ID: mdl-39080213

RESUMO

New wound dressings based on polymeric membranes have been widely exploited for clinical applications to assist in the healing process and prevent additional complications (e.g., bacterial infections). Here we propose the development of a new production method of polymeric membranes based on chitosan, incorporating glycolic extract of Aloe vera with joint synthesis of silver nanoparticles for use as a new bioactive dressing. The membranes were obtained by casting technique, and their morphological, physicochemical characteristics, degree of swelling, degradation profile and antimicrobial activity evaluated. Morphological analyzes confirmed the synthesis and presence of silver nanoparticles in the polymeric membrane. The chemical compatibility between the materials was demonstrated through thermal analysis (TGA and DSC) combined with ATR-FTIR tests, showing the complexation of the membranes (Mb-Ch-Ex.Av-NPs). All membranes were characterized as hydrophilic material (with a contact angle (Ó©) < 90°); however, the highest degree of swelling was obtained for the chitosan. (Mb-Ch) membrane (69.91 ± 5.75%) and the lowest for Mb-Ch-Ex.Av-NPs (26.62 ± 8.93%). On the other hand, the degradation profile was higher for Mb-Ch-Ex.Av-NPs (77.85 ± 7.51%) and lower for Mb-Ch (57.60 ± 2.29%). The manufactured bioactive dressings showed activity against Escherichia coli and Staphylococcus aureus. Our work confirmed the development of translucent and flexible chitosan-based membranes, incorporating Aloe vera glycolic extract with joint synthesis of silver nanoparticles for use as a new bioactive dressing, with proven antimicrobial activity.

3.
Biosensors (Basel) ; 14(6)2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38920603

RESUMO

Nowadays, biosensors are gaining increasing interest in foods' and beverages' quality control, owing to their economic production, enhanced sensitivity, specificity, and faster analysis. In particular, colorimetric biosensors can be combined with color recognition applications on smartphones for the detection of analytes, rendering the whole procedure more applicable in everyday life. Herein, chitosan (CS) films were prepared with the deep eutectic solvent (DES) choline chloride/urea/glycerol (ChCl:U:Gly). Glucose oxidase (GOx), a widely utilized enzyme in quality control, was immobilized within CS films through glutaraldehyde (GA), leading to the formation of CS/GOx films. The optimized GOx concentration and DES content were determined for the films. Moreover, the effect of the pH and temperature of the glucose oxidation reaction on the enzymatic activity of GOx was studied. The structure, stability, and specificity of the CS/GOx films as well as the Km values of free and immobilized GOx were also determined. Finally, the analytical performance of the films was studied by using both a spectrophotometer and a color recognition application on a smartphone. The results demonstrated that the films were highly accurate, specific to glucose, and stable when stored at 4 °C for 4 weeks and when reused 10 times, without evident activity loss. Furthermore, the films displayed a good linear response range (0.1-0.8 mM) and a good limit of detection (LOD, 33 µM), thus being appropriate for the estimation of glucose concentration in real samples through a smartphone application.


Assuntos
Bebidas , Técnicas Biossensoriais , Quitosana , Colorimetria , Glucose Oxidase , Glucose , Smartphone , Quitosana/química , Glucose/análise , Bebidas/análise , Glucose Oxidase/química , Enzimas Imobilizadas/química
4.
Polymers (Basel) ; 16(5)2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38475259

RESUMO

Currently, natural polymer materials with bactericidal properties are extremely popular. Unfortunately, although the biopolymer material itself is biodegradable, its enrichment with bactericidal compounds may affect the efficiency of biodegradation by natural soil microflora. Therefore, the primary objective of this study was to evaluate the utility of fungi belonging to the genus Trichoderma in facilitating the degradation of chitosan film modified with cinnamic acid and ellagic acid in the soil environment. Only two strains (T.07 and T.14) used chitosan films as a source of carbon and nitrogen. However, their respiratory activity decreased with the addition of tested phenolic acids, especially cinnamic acid. Addition of Trichoderma isolates to the soil increased oxygen consumption during the biodegradation process compared with native microorganisms, especially after application of the T.07 and T.14 consortium. Isolates T.07 and T.14 showed high lipolytic (55.78 U/h and 62.21 U/h) and chitinase (43.03 U/h and 41.27 U/h) activities. Chitinase activity after incorporation of the materials into the soil was higher for samples enriched with T.07, T.14 and the consortium. The isolates were classified as Trichoderma sp. and Trichoderma koningii. Considering the outcomes derived from our findings, it is our contention that the application of Trichoderma isolates holds promise for expediting the degradation process of chitosan materials containing bactericidal compounds.

5.
Biomolecules ; 14(3)2024 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-38540743

RESUMO

Laccase from Trametes versicolor was applied to produce phenolic polymeric compounds with enhanced properties, using a wine lees extract as the phenolic source. The influence of the incubation time on the progress of the enzymatic oxidation and the yield of the formed polymers was examined. The polymerization process and the properties of the polymeric products were evaluated with a variety of techniques, such as high-pressure liquid chromatography (HPLC) and gel permeation chromatography (GPC), Fourier-transform infrared (FTIR) and nuclear magnetic resonance (NMR) spectroscopies, differential scanning calorimetry (DSC), and thermogravimetric analysis (TGA). The enzymatic polymerization reaction resulted in an 82% reduction in the free phenolic compounds of the extract. The polymeric product recovery (up to 25.7%) and the molecular weight of the polymer depended on the incubation time of the reaction. The produced phenolic polymers exhibited high antioxidant activity, depending on the enzymatic oxidation reaction time, with the phenolic polymer formed after one hour of enzymatic reaction exhibiting the highest antioxidant activity (133.75 and 164.77 µg TE mg-1 polymer) towards the ABTS and DPPH free radicals, respectively. The higher thermal stability of the polymeric products compared to the wine lees phenolic extract was confirmed with TGA and DSC analyses. Finally, the formed phenolic polymeric products were incorporated into chitosan films, providing them with increased antioxidant activity without affecting the films' cohesion.


Assuntos
Antioxidantes , Vinho , Antioxidantes/química , Lacase/química , Vinho/análise , Polímeros/química , Trametes , Embalagem de Alimentos , Fenóis/química , Extratos Vegetais/análise
6.
MethodsX ; 12: 102583, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38313694

RESUMO

The chitosan films were prepared from shrimp, squid, and crab to corroborate that regardless of the source of the chitosan, it was possible to measure the degree of deacetylation. In this work, the degree of deacetylation of chitosan was evaluated via UV, FTIR and 1H NMR spectrophotometry methodologies. Values in a range of 74 to 99% degree of deacetylation (DD) were obtained and varied depending on the method used and the source of chitosan. The spectrophotometric method is one of the most commonly used for this determination; however, it has the limitation that D-glucosamine and N-acetylglucosamine share similar wavelengths. All three methods were simple and provided rapid analysis; however, NMR, in particular, was expensive due to its equipment specifications. For this reason, its important to select the simplest method than can be routinely used.•The simplest used technique to determine the degree of deacetylation is infrared spectroscopy.•The degree of acetylation of chitosan is related to its physicochemical properties; its determination is an important parameter due to its association with chitosan applications in different industrial areas.•The 1H NMR method is very precise and requires expensive equipment and trained personal. Thus, it cannot be used routinely to determine the degree of deacetylation.

7.
J Photochem Photobiol B ; 251: 112850, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38277961

RESUMO

The effect of UV radiation from three different sources on chitosan (CS) films containing the addition of 10% by weight of cannabis oil was investigated. Cannabis oil (CBD) alone exposed to UV is unstable, but its photostability significantly increases in the chitosan matrix. The course of photochemical reactions, studied by FTIR spectroscopy, is slow and inefficient in chitosan with CBD, even under high-energy UV sources. The research also included chitosan films with CBD cross-linked with dialdehyde starch (DAS). Using AFM microscopy and contact angle measurements, the morphology and surface properties of prepared chitosan films with CBD were investigated, respectively. It was found that CBD embedded in CS is characterized by the best photostability under the influence of an LED emitting long-wave radiation. Using a monochromatic and polychromatic UV lamp (HPK and UV-C) emitting high-energy radiation, gradual degradation accompanied by oxidation was observed, both in the CS chains and in the CBD additive. Additionally, changes in surface properties are observed during UV irradiation. It was concluded that CS protects CBD against photodegradation, and a further improvement in photochemical stability is achieved after system cross-linking with DAS.


Assuntos
Cannabis , Quitosana , Quitosana/química , Raios Ultravioleta , Propriedades de Superfície , Microscopia Eletrônica de Varredura
8.
Int J Biol Macromol ; 253(Pt 8): 127544, 2023 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-37866570

RESUMO

Photodynamic therapy is an alternative treatment for several pathologies, including cancer. This therapy uses a photosensitizer capable of producing reactive oxygen species through irradiation, promoting cellular death. A limitation of photosensitizers is their low solubility in aqueous media. Hence, developing a suitable carrier for photosensitizers for specific applications is a challenge. Cervical cancer is one of the most common cancers in women, and photodynamic therapy could be an attractive alternative therapeutic approach. In this work, we synthesized films composed of chitosan, polyvinylpyrrolidone, and liposomes containing Zn-phthalocyanine. Photophysical characterization of ZnPc incorporated into films was determined by UV-vis and fluorescence. Film properties such as swelling, mechanical properties, and water vapor permeability were performed. Finally, in vitro, photodynamic evaluation of these films was performed on HeLa cells. The results indicate that incorporating Zn-Pc-liposomes into films decreases cell viability by >95 %.


Assuntos
Quitosana , Compostos Organometálicos , Fotoquimioterapia , Feminino , Humanos , Lipossomos , Fármacos Fotossensibilizantes/farmacologia , Células HeLa , Fotoquimioterapia/métodos , Compostos de Zinco
9.
Foods ; 12(18)2023 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-37761228

RESUMO

The impact of synthetic packaging on environmental pollution has been observed for years. One of the recent trends of green technology is the development of biomaterials made from food processing waste as an alternative to plastic packaging. Polymers obtained from some polysaccharides, such as chitosan, could be an excellent solution. This study investigated the biodegradability of chitosan-metal oxide films (ZnO, TiO2, Fe2O3) and chitosan-modified graphene films (CS-GO-Ag) in a soil environment. We have previously demonstrated that these films have excellent mechanical properties and exhibit antibacterial activity. This study aimed to examine these films' biodegradability and the possibility of their potential use in the packaging industry. The obtained results show that soil microorganisms were able to utilize chitosan films as the source of carbon and nitrogen, thus providing essential evidence about the biodegradability of CS, CS:Zn (20:1; 10:1), and CS:Fe2O3 (20:1) films. After 6 weeks of incubation, the complete degradation of the CS-Fe2O3 20:1 sample was noted, while after 8 weeks, CS-ZnO 20:1 and CS-ZnO 10:1 were degraded. This is a very positive result that points to the practical aspect of the biodegradability of such films in soil, where garbage is casually dumped and buried. Once selected, biodegradable films can be used as an alternative to plastic packaging, which contributes to the reduction in pollution in the environment.

10.
Int J Biol Macromol ; 253(Pt 3): 126466, 2023 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-37659494

RESUMO

Early fire detection is an efficient method to mitigate disastrous fire loss. However, developing smart low-temperature fire-warning sensors that better diminish fire hazards, especially those caused by household appliances, is still challenging. Herein, a salts-modified chitosan (salts-modified CS) based sensor with integrated fire-warning and humidity-monitoring capability is proposed using an easy assembling method. This sensor can respond to temperatures as low as 50 °C and a flame within 2 s quickly and detect relative humidity (RH) range above 50 % at 50 °C and 75 °C sensitively. This system can be reusable for multiple ignitions and works in high-humidity environments (>50 %). Furthermore, the comparison between different salts-modified CS films is carried out to elucidate the mechanism of the formation of electric current under the joint driven by temperature and humidity. Moreover, real-time temperature and RH monitoring can be achieved with a wireless transmission section. This design shows a promising approach for multifunctional CS-based sensors and paves a path to developing a new generation of smart fire-warning detectors.


Assuntos
Quitosana , Umidade , Sais , Temperatura , Temperatura Baixa
11.
J Funct Biomater ; 14(7)2023 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-37504853

RESUMO

Chitosan is a natural and biodegradable polymer with promising potential for biomedical applications. This study concerns the production of chitosan-based materials for future use in the medical industry. Bioactive substances-caffeine and ethanolic propolis extract (EEP)-were incorporated into a chitosan matrix to increase the bioactivity of the obtained films and improve their mechanical properties. Acetic and citric acids were used as solvents in the production of the chitosan-based films. The obtained materials were characterized in terms of their antibacterial and antifungal activities, as well as their mechanical properties, including tensile strength and elongation at break. Moreover, the chemical structures and surface morphologies of the films were assessed. The results showed that the solution consisting of chitosan, citric acid, caffeine, and EEP exhibited an excellent antiradical effect. The activity of this solution (99.13%) was comparable to that of the standard antioxidant Trolox (92.82%). In addition, the film obtained from this solution showed good antibacterial activity, mainly against Escherichia coli and Enterococcus faecalis. The results also revealed that the films produced with citric acid exhibited higher activity levels against pathogenic bacteria than the films obtained with acetic acid. The antimicrobial effect of the chitosan-based films could be further enhanced by adding bioactive additives such as caffeine and propolis extract. The mechanical tests showed that the solvents and additives used affected the mechanical properties of the films obtained. The film produced from chitosan and acetic acid was characterized by the highest tensile strength value (46.95 MPa) while the chitosan-based film with citric acid showed the lowest value (2.28 MPa). The addition of caffeine and propolis to the film based on chitosan with acetic acid decreased its tensile strength while in the case of the chitosan-based film with citric acid, an increase in strength was observed. The obtained results suggested that chitosan films with natural bioactive substances can be a promising alternative to the traditional materials used in the medical industry, for example, as including biodegradable wound dressings or probiotic encapsulation materials.

12.
Int J Mol Sci ; 24(13)2023 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-37445916

RESUMO

Antibacterial chitosan films, versatile and eco-friendly materials, have garnered significant attention in both the food industry and medicine due to their unique properties, including biodegradability, biocompatibility, and antimicrobial activity. This review delves into the various types of chitosan films and their distinct applications. The categories of films discussed span from pure chitosan films to those enhanced with additives such as metal nanoparticles, metal oxide nanoparticles, graphene, fullerene and its derivatives, and plant extracts. Each type of film is examined in terms of its synthesis methods and unique properties, establishing a clear understanding of its potential utility. In the food industry, these films have shown promise in extending shelf life and maintaining food quality. In the medical field, they have been utilized for wound dressings, drug delivery systems, and as antibacterial coatings for medical devices. The review further suggests that the incorporation of different additives can significantly enhance the antibacterial properties of chitosan films. While the potential of antibacterial chitosan films is vast, the review underscores the need for future research focused on optimizing synthesis methods, understanding structure-property relationships, and rigorous evaluation of safety, biocompatibility, and long-term stability in real-world applications.


Assuntos
Quitosana , Nanopartículas Metálicas , Quitosana/farmacologia , Antibacterianos/farmacologia , Óxidos , Filmes Cinematográficos , Embalagem de Alimentos/métodos
13.
Nanomaterials (Basel) ; 13(3)2023 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-36770445

RESUMO

Healthcare-associated infections (HAIs) represent a global burden, leading to significant mortality and generating financial costs. One important cause of HAIs is the microbiological contamination of implantable medical devices. In this context, a novel antimicrobial drug-eluting system, based on chitosan and loaded with gentamicin, a broad-spectrum antibiotic, was developed. The effects of the addition of tannic acid and different FeSO4 concentrations on the loaded antibiotic release were evaluated. The properties of the films were assessed in terms of thickness, swelling, mass loss and wettability. The films' surface composition was characterized by X-ray photoelectron spectroscopy and Fourier-transform infrared spectroscopy. The antibiotic release in phosphate buffer saline was quantified by high-performance liquid chromatography-mass spectrometry, and the antibacterial activity was evaluated. Hemolysis and cytotoxicity were also assessed. The results showed that the addition of tannic acid and iron decreased the swelling degree and degradation due to strong interactions between the different components, thus impacting gentamicin release for up to 35 days. In conclusion, this study presents a novel strategy to produce low-cost and biocompatible antimicrobial drug-eluting systems with sustained and prolonged antibacterial activity over more than a month.

14.
Carbohydr Polym ; 302: 120438, 2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36604094

RESUMO

In this work, chemical modification of chitosan using cationic thiazolium groups was investigated with the aim to improve water solubility and antimicrobial properties of chitosan. Enzymatic synthesis and ethyl-3-(3-dimethylaminopropyl) carbodiimide/N-hydroxysuccinimide (EDC/NHS) chemistry were employed to synthesize and attach to chitosan through the amine groups the molecule bearing thiazolium moieties, quaternized 4-(2-(4-methylthiazol-5-yl) ethoxy)-4-oxobutanoic acid (MTBAQ). On the basis of Fourier transform infrared spectroscopy (FTIR), elemental analysis and solid state nuclear magnetic resonance (ssNMR), around 95 % of the available amine groups of chitosan (of 25 % degree of acetylation) reacted. The resulting derivative was water soluble at physiological pH and exhibit excellent antimicrobial activity against Listeria innocua, Staphylococcus epidermidis, Staphylococcus aureus and Methicillin Resistant S. aureus Gram-positive bacteria (MIC = 8-32 µg/ mL), whereas its efficiency decreases against fungi Candida albicans and Eschericia coli Gram-negative bacterium. Subsequently, the thiazolium chitosan derivative was employed as antimicrobial component (up to 7 wt%) of chitosan/glycerol based films. The incorporation of the chitosan derivative does not modify significantly the characteristics of the film in terms of thermal and mechanical properties, while enhances considerably the antimicrobial activity.


Assuntos
Anti-Infecciosos , Quitosana , Staphylococcus aureus Resistente à Meticilina , Quitosana/química , Anti-Infecciosos/farmacologia , Anti-Infecciosos/química , Água , Aminas , Espectroscopia de Infravermelho com Transformada de Fourier , Antibacterianos/farmacologia , Antibacterianos/química
15.
Int J Pharm ; 634: 122648, 2023 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-36709832

RESUMO

Chitosan films are commonly used for wound dressing, provided that this polymer has healing, mucoadhesiveness and antimicrobial properties. These properties can be further reinforced by the combination of chitosan with polysaccharides and glycoproteins present in aloe vera, together with copaiba oleoresin's pharmacological activity attributed to sesquiterpenes. In this work, we developed chitosan films containing either aloe vera, copaiba oil or both, by casting technique, and evaluated their microbial permeation, antimicrobial activity, cytotoxicity, and in vivo healing potential in female adult rats. None of the developed chitosan films promoted microbial permeation, while the cytotoxicity in Balb/c 3 T3 clone A31 cell line revealed no toxicity of films produced with 2 % of chitosan and up to 1 % of aloe vera and copaiba oleoresin. Films obtained with either 0.5 % chitosan or 0.5 % copaiba oleoresin induced cell proliferation which anticipate their potential for closure of wound and for the healing process. The in vivo results confirmed that tested films (0.5 % copaiba-loaded chitosan film and 0.5 % aloe vera-loaded chitosan film) were superior to a commercial dressing film. For all tested groups, a fully formed epithelium was seen, while neoformation of vessels seemed to be greater in formulations-treated groups than those treated with the control. Our work confirms the added value of combining chitosan with aloe vera and copaiba oil in the healing process of wounds.


Assuntos
Aloe , Anti-Infecciosos , Quitosana , Feminino , Ratos , Animais , Anti-Infecciosos/farmacologia , Bandagens
16.
Polymers (Basel) ; 14(23)2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36501631

RESUMO

Three chitosans with different morphologies have been used (commercial chitosan powder, chitosan in film form and chitosan in globular form synthesized by the freeze-dried method) for the synthesis of biochars. The pyrolytic treatment has revealed that the biochar synthesized from the chitosan formed by the freeze-dried method reaches the highest CO2-adsorption capacity (4.11 mmol/g at 0 °C and a pressure of 1 bar) due to this adsorbent is highly microporous. Moreover, this biochar is more resistant to the pyrolytic treatment in comparison to the biochars obtained from the commercial chitosan and chitosan in the form of film. CO2-adsorption studies at different temperatures have also shown that the adsorption capacity diminishes as the adsorption temperature increases, thus suggesting that the adsorption takes place by a physical process.

17.
Foods ; 11(21)2022 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-36360041

RESUMO

Chitosan-genipin (Ch-Ge) films have been proposed for the replacement of sulfur dioxide (SO2) in white wines preservation to circumvent the adverse health consequences caused by SO2 intake. To assess the effects of different-sized Ch-Ge films (25 and 100 cm2) on wine composition compared to SO2-treated and untreated wines, nuclear magnetic resonance metabolomics was applied. Relative to SO2, 100 cm2 films induced significant changes in the levels of organic acids, sugars, amino acids, 5-hydroxymethylfurfural, among other compounds, while 25 cm2 films appeared to induce only small variations. The observed metabolite variations were proposed to arise from the mitigation of fermentative processes, electrostatic interactions between acids and the positively charged films and the promotion of Maillard and Strecker reactions. Qualitative sensory analysis showed that wines maintained overall appropriate sensory characteristics, with 100 cm2 film treated wines showing slightly higher attributes. Based on these results, the possibility of using Ch-Ge films as a replacement for SO2 treatment is discussed.

18.
Food Chem ; 395: 133605, 2022 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-35802976

RESUMO

In this work, the film-forming properties of chitosan with different molecular weights (MW) (30, 100, 200 and 300 kDa) and its adhesion properties with different postharvest fruit surfaces were analyzed. The viscosity of 30 and 300 kDa chitosan film-forming solution gradually increased from 0.007 to 1.16 Pa.s at a shear rate of 10 s-1. Compared to 30 kDa chitosan films, higher MW chitosan films showed enhanced water resistance, water vapor barrier properties and mechanical properties, mainly due to the different strength of interaction forces within the chitosan films, which can be confirmed by microstructural observations and FTIR results of the films. It can be found that different MW chitosan film surfaces with bananas, apples, pears, oranges and strawberries all have a similar adhesion work of about 70-80 mN m-1, and 100 and 200 kDa chitosan film had higher adhesion work with different fruit surfaces compared to 30 and 300 kDa.


Assuntos
Quitosana , Pyrus , Quitosana/química , Frutas/química , Peso Molecular , Vapor/análise
19.
Int J Biol Macromol ; 217: 572-582, 2022 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-35810854

RESUMO

This study includes development of chitosan-based films with incorporated essential thyme oil and different combinations of cross-linkers viz., ZnO, CaCl2, NC, and PEG for the safe storage of sweet cherries. The resulting films stored with sweet cherries were analyzed for different physicochemical and antimicrobial properties. Incorporation of ZnO, CaCl2, NC, and PEG in chitosan-based films maintained fruit quality by conserving higher total soluble solids, titratable acidity, and reduced weight loss. The combined ZnO + CaCl2 + NC + PEG in chitosan-based films also suppressed microbial activity. The sensorial quality of fruits stored with CH + ZnO + CaCl2 + NC + PEG treatment was also stable during storage. In conclusion, the combined CH + ZnO + CaCl2 + NC + PEG with added thyme oil application is an effective approach to maintain the postharvest quality and could be an alternative to increase the shelf life of sweet cherries, besides decreasing environmental impacts of non-biodegradable packages.


Assuntos
Quitosana , Óleos Voláteis , Prunus avium , Óxido de Zinco , Cloreto de Cálcio , Quitosana/química , Argila , Embalagem de Alimentos/métodos , Humanos , Cuidados para Prolongar a Vida , Óleos Voláteis/farmacologia , Óleos de Plantas , Polietilenoglicóis , Timol , Thymus (Planta) , Óxido de Zinco/química
20.
Gels ; 8(6)2022 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-35735671

RESUMO

The recent interest in food biopackaging is showing an increasing trend, especially in the development of antimicrobial coatings and films. The focus of this study is to assess the potential application of ginger (Zingiber officinale) essential oil (GEO) to polysaccharide films based on chitosan (CHf) and their utilization as an active edible packaging. The films were characterized by different instrumental techniques, and data indicated significant differences (p < 0.05) in the chemical composition of the samples. Forty-seven active compounds from ginger rhizomes were identified in the examined essential oil by gas chromatography mass spectrometer (GC-MS). Fourier transforms infrared spectra (FT-IR) confirmed an interaction between the hydroxyl groups of the phenolic compounds of the essential oil and the amine groups of the bioactive matrix, as shown by the peaks at wavenumbers 1639 cm−1 and 1558 cm−1. X-ray diffraction data suggested a lower crystallinity in the CHf due to the addition of GEO. Differential scanning calorimetric (DSC) analysis revealed that the CHf possessed high thermal stability, especially when different concentrations of GEO were added. The bioactive CHf showed distinct activity against both Gram-positive and Gram-negative bacteria, such as Staphylococcus aureus, Bacillus subtilis, Streptococcus sp., Escherichia coli, Salmonella sp., and Pseudomonas aeruginosa, thus improving the antimicrobial activity to these films. The results provide a comprehensive insight into the importance of films with incorporated EOs as novel types of active food packaging. Antimicrobial food packaging is one of the most promising kinds of active packaging, and acts to reduce, inhibit, or retard any microorganism growth that could contaminate packaged food items.

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