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1.
Food Chem ; 371: 131372, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-34808772

RESUMO

To investigate antibacterial properties and application in food preservation of nanofibrous films (NFs), baicalin-liposomes (BCL-LPs) were loaded into polyvinyl alcohol-chitosan (PVA-CS) substrates to form NFs using electrospinning technology. The microstructure and phase identification of the NFs were characterized. The antibacterial properties and cytotoxicity of NFs were determined. The preservation of the NFs to mushrooms was evaluated. The results showed that smooth and uniform NFs were formed through molecular interaction between BCL-LPs and PVA-CS matrix. The NFs exhibited good antibacterial effects on Escherichia coli and Staphylococcus aureus due to the bacterial destruction resulting from the BCL delivery to bacterial cells by liposomes. In addition, the NFs were compatible with L929 fibroblasts. The BCL-LPs/PVA-CS NFs inhibited weight loss, browning, rancidity and bacterial growth as well as maintained the nutrients of mushrooms. The results show BCL-LPs/PVA-CS NFs possessed effective antibacterial properties, non-cytotoxicity and preservation performance, indicating the potential utilization as food-active packing.


Assuntos
Agaricales , Quitosana , Nanofibras , Antibacterianos/farmacologia , Flavonoides , Lipossomos , Álcool de Polivinil
2.
Colloids Surf B Biointerfaces ; 209(Pt 1): 112191, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34781078

RESUMO

Bacterial infections have become one of the top ten public health concerns worldwide. These problems are aggravated with the emergence of multi-drug resistant bacterial strains. Thus, it is necessary to adopt novel technological strategies, such as development of bionanomaterials to prevent the infection, and treat this kind of bacteria. At this regard, the chemical modification of chitosan (Cs), by the covalent attachment of a hydrocarbon chain (octanoic acid), was developed to obtain hydrophobic chitosan (HCs). Then, HCs was used to synthetize nanoparticles using the well-known ionotropic gelation approach, optimizing the parameters, such as the TPP/HCs ratio and pH solution to get stable nanoparticles. Then, carvacrol (CAR) was loaded into NPs (HCs-CAR NPs) using different concentrations of 25%, 50% and 75% (%w/w CAR/HCs). The physicochemical properties for HCs-CAR NPs prepared at 50% of CAR stood out from the rest, showing a spherical morphology, with a size of 200 nm, Z potential of 10.4 mV and encapsulation efficiency of 56.28%. These formulations were chosen to evaluate the antibacterial activity, using Gram-negative (Escherichia coli) and Gram-positive bacterial model (Staphylococcus aureus). The HCs-CAR NPs showed great activity against both bacterial models, being more effective against Gram (+) strain (S. aureus), suggesting the potential application of these NPs as novel biomaterial to treat bacterial infection.


Assuntos
Quitosana , Nanopartículas , Antibacterianos/farmacologia , Cimenos , Tamanho da Partícula , Staphylococcus aureus
3.
Colloids Surf B Biointerfaces ; 209(Pt 1): 112207, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34800810

RESUMO

Multifunctional wound dressings urgently need to be developed to meet the various needs of wound healing. In this work, we first proposed a new method about modifying the guar gum (GG) by performing a quaternization graft reaction and then oxidation. The obtained oxidized quaternized guar gum (OQGG) not only has antibacterial function due to the introduction of quaternary ammonium groups, but also can become one of the components of Schiff base hydrogels due to the presence of aldehyde groups. Therefore, we used it and carboxymethyl chitosan (CMCS) to design a hydrogel with antibacterial, hemostatic, self-repairing and injectable properties. We characterized the structure of OQGG and OQGG@CMCS hydrogels, but also evaluated the performance of the hydrogels. The results showed that GG was successfully modified to OQGG and OQGG@CMCS hydrogel was successfully prepared, and the obtained OQGG@CMCS hydrogel showed excellent antibacterial and hemostatic properties, and exhibited self-healing and injectability. In addition, cytotoxicity tests demonstrated that the OQGG@CMCS hydrogels presented good cytocompatibility. Further, the OQGG@CMCS hydrogel significantly promoted wound healing in an S. aureus-infected rat wound model. Therefore, the hydrogel has the potential to be applied as a wound dressing.


Assuntos
Quitosana , Hemostáticos , Animais , Antibacterianos/farmacologia , Bandagens , Galactanos , Hemostáticos/farmacologia , Hidrogéis , Mananas , Gomas Vegetais , Ratos , Staphylococcus aureus
4.
Food Chem ; 366: 130530, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34303204

RESUMO

In this study, the effects of different temperatures, incubation times and types of reducing sugars, including glucose and different low molecular weight (Mw) chito-oligosaccharides (COS) with varying acetylation degree (AD), on the extent of Maillard reaction (MR) on chitosan-based films were studied. Interestingly, an improvement of structural and functional properties of all MR-crosslinked films was noted, which is more pronounced by heating at higher temperature and exposure time. These findings were proved through Fourier-transform infrared and X-ray diffraction analyses. In addition, color change and Ultraviolet spectra demonstrate that glucose addition provides the high extent of MR, followed by COS1 (Mw < 4.4 kDa; AD, 18.20%) and COS2 (Mw < 4.4 kDa; AD, 10.63%). These results were confirmed by enhanced water resistance and thermal properties. Moreover, MR-chitosan/COS films showed the highest mechanical properties, whereas, glucose-loaded films were brittle, as demonstrated by scanning electron microscopy micrographs. Furthermore, MR-chitosan/COS1 films exhibited the better antioxidant behavior followed by chitosan/glucose and chitosan/COS2 films, mainly at higher heating-conditions. Thereby, MR-crosslinked chitosan/COS based films were attractive to be applied as functional and active coating-materials in various fields.


Assuntos
Quitosana , Antioxidantes , Glucose , Reação de Maillard , Peso Molecular , Espectroscopia de Infravermelho com Transformada de Fourier
5.
Food Chem ; 366: 130574, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34303209

RESUMO

There is growing interest in chitosan-based intelligent packaging films for monitoring food quality. However, practical application of these biopolymeric films has been limited by their poor physical and mechanical attributes. Herein, a versatile colorimetric indicator film was developed based on chitosan (CHI) and broken Riceberry phenolic extract (RPE). The effects of RPE fortification on the microstructure, physical, and functional attributes of the CHI films were comprehensively evaluated. The results revealed that CHI-RPE films exhibited increased hydrophobicity, mechanical resistance, thermal stability, barrier properties, and antioxidant activity compared to plain CHI film. The CHI-RPE films were cytocompatible. Notably, CHI-RPE film also produced intense naked-eye detectable colorimetric response to pH (2-12) variation and volatile ammonia. When enclosed with fresh shrimp, CHI-RPE film changed from orange-red to yellow in response to shrimp spoilage. Thus, CHI-RPE film has high potential for fabricating pragmatic, smart packaging labels for on-site visual detection of freshness in seafood products.


Assuntos
Quitosana , Antocianinas , Antioxidantes , Embalagem de Alimentos , Concentração de Íons de Hidrogênio , Extratos Vegetais , Alimentos Marinhos/análise
6.
Food Chem ; 366: 130616, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34311240

RESUMO

The lipase from Bacillus licheniformis NCU CS-5 was immobilized onto ß-cyclodextrin (CD) grafted and aminopropyl-functionalized chitosan-coated Fe3O4 magnetic nanocomposites (Fe3O4-CTS-APTES-GA-ß-CD). Fourier transform infrared spectroscopy, thermogravimetry analysis, X-ray diffraction, scanning electron microscopy and transmission electron microscopy showed that not only the functionalized magnetic nanoparticles were synthesized but also the immobilized lipase was successfully produced. The immobilized lipase exhibited higher optimal pH value (10.5) and temperature (60℃) than the free lipase. The pH and thermal stabilities of the immobilized lipase were improved significantly compared to the free lipase. The immobilized lipase remained more than 80% of the relative activity at temperature of 60 ℃ and pH 12.0. The immobilized lipase also remained over 80% of its relative activity after 28 days of storage and 15 cycles of application. The application of the immobilized lipase in esterification of isoamyl acetate and pentyl valerate showed that maximum esterification efficiency was achieved in n-hexane having 68.0% and 89.2% respectively. Therefore, these results indicated that the Fe3O4-CTS-APTES-GA-ß-CD nanoparticles are novel carriers for immobilizing enzyme, and the immobilized lipase can be used as an innovative green approach to the synthesis of fruity flavor esters in food industry.


Assuntos
Quitosana , Ciclodextrinas , Nanopartículas de Magnetita , Nanocompostos , Estabilidade Enzimática , Enzimas Imobilizadas/metabolismo , Esterificação , Ésteres , Concentração de Íons de Hidrogênio , Lipase/metabolismo , Fenômenos Magnéticos
7.
J Colloid Interface Sci ; 605: 82-90, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34311315

RESUMO

A highly stable Pd-loaded N-doped carbon catalyst (ACNpd) for phenol hydrogenation was prepared from chitosan by hydrothermal carbonization. ACNpd does not require a reduction step before catalytic use due to the Pd in the as-prepared catalyst mainly exists in the form of Pd0 (80%). The carbon support involves N-containing groups such as pyridinic nitrogen and pyrrolic nitrogen, which could provide basic sites to adsorb phenol effectively. The as-fabricated ACNpd shows high catalytic performance with turnover frequency (TOF) of 29.34 h-1. Accordingly, a phenol conversion of 100% and a cyclohexanone selectivity of 99.1% are achieved in 5 h at 100 °C and 1 MPa H2. This outstanding performance is attributed to the synergetic effects of the Pd particles, the N-functional groups, and the Lewis acid sites on the support. The carbon support presents intrinsic Lewis acid sites due to its electrophilicity, and Pd doping further increases the strength of such acid sites as it causes electron-deficient structural features. Moreover, the Lewis acid sites inhibit the over-hydrogenation from cyclohexanone to cyclohexanol. This study provides new insights into the application of functional biomass-based carbon materials as catalyst supports.


Assuntos
Carbono , Quitosana , Cicloexanonas , Hidrogenação , Fenol , Fenóis
8.
Biochim Biophys Acta Biomembr ; 1864(1): 183779, 2022 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-34560046

RESUMO

Biophysical characterization of antimicrobial peptides helps to understand the mechanistic aspects of their action. The physical behavior of the KR-12 antimicrobial peptide (e.g. orientation and changes in secondary structure), was analyzed after interactions with a Staphylococcus aureus membrane model and solid surfaces. We performed antimicrobial tests using Gram-positive S. aureus (ATCC 25923) bacteria. Moreover, Langmuir-Blodgett experiments showed that the synthetic peptide can disturb the lipidic membrane at a concentration lower than the Minimum Inhibitory Concentration, thus confirming that KR-12/lipid interactions are involved. Partially- and fully-deactivated KR-12 hybrid samples were obtained by physisorption and covalent immobilization in chitosan/silica and glyoxal-rich solid supports. The correlation of Langmuir-Blodgett data with the α-helix formation, followed by FTIR-ATR in a frozen-like state, and the antimicrobial activity showed the importance of these interactions and conformation changes on the first step action mode of this peptide. This is the first time that material science (immobilization in solid surfaces assisted by FTIR-ATR analysis in frozen-like state) and physical (Langmuir-Blodgett/Schaefer) approaches are combined for exploring mechanistic aspects of the primary action mode of the KR-12 antimicrobial peptide against S. aureus.


Assuntos
Antibacterianos/química , Catelicidinas/química , Lipídeos/antagonistas & inibidores , Fragmentos de Peptídeos/química , Antibacterianos/farmacologia , Catelicidinas/farmacologia , Quitosana/química , Quitosana/farmacologia , Humanos , Lipídeos/química , Lipídeos de Membrana/antagonistas & inibidores , Testes de Sensibilidade Microbiana , Fragmentos de Peptídeos/farmacologia , Espectroscopia de Infravermelho com Transformada de Fourier , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/patogenicidade
9.
Pestic Biochem Physiol ; 180: 105001, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34955184

RESUMO

The chitosan nanomatrix incorporated with Cymbopogon citratus essential oil (Ne-CcEO) possess enhanced efficacy against the food-borne molds and aflatoxin B1 production compared to free essential oil. The CcEO was encapsulated inside the chitosan nanomatrix with an average size 147.41 ± 16.18 nm and characterized by Scanning electron microscopy, Fourier transforms infrared spectroscopy, and X-ray diffraction assay. The encapsulation efficiency and loading capacity were ranged between (41.68-76.78%) and (5.3-8.80%). The biochemical and in-silico analysis results revealed the interference in functioning of membrane integrity, mitochondrial membrane potential, antioxidant defense, carbon source metabolism, methylglyoxal, and laeA gene in response to treatment of Ne-CcEO (0.5 µl/ml). In addition, Ne-CcEO significantly protects the deterioration of Pennisetum glaucum (L.) R. Br. seed samples by A. flavus, aflatoxin B1 contamination, and lipid peroxidation. The Ne-CcEO could be considered as promising antifungal additives for the control of food-borne molds and aflatoxin B1 contamination in the food system.


Assuntos
Quitosana , Cymbopogon , Óleos Voláteis , Aflatoxina B1 , Antifúngicos/farmacologia , Aspergillus flavus , Quitosana/farmacologia , Óleos Voláteis/farmacologia
10.
J Environ Sci (China) ; 112: 202-209, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34955204

RESUMO

Arsenic (As) contamination poses an urgent environmental risk, and its removal from groundwater remains a challenge due to the lack of efficient adsorbents. Herein, a novel granular chitosan-titanium (CS-Ti) adsorbent was fabricated by the sol-gel method. Batch experiments show that As(V) adsorption on CS-Ti followed the pseudo-second-order kinetic model, and the adsorption isotherm conformed to the Freundlich model with the correlation coefficient of 0.99. In situ FTIR spectra revealed that the CS-Ti adsorbent was composed of amorphous TiOx and chitosan by forming C-O-Ti and N-Ti bonds, and the amorphous TiOx was responsible for As(V) adsorption. Rapid small-scale column tests show that 165.6 µg/L of As in groundwater were effectively removed in approximately 126-bed volumes, and the spent adsorbents were regenerated with 0.01 mol/L NaOH and maintained the adsorption efficiency after four cycles. This study provides a simple and practical route to fabricate adsorbents for water treatment.


Assuntos
Arsênio , Quitosana , Água Subterrânea , Poluentes Químicos da Água , Purificação da Água , Adsorção , Concentração de Íons de Hidrogênio , Cinética , Titânio , Poluentes Químicos da Água/análise
11.
J Mech Behav Biomed Mater ; 125: 104975, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34823087

RESUMO

The subject of this paper is to develop a highly conductive Graphene nanoplatelets (GNPs)-Chitosan (CS)/Polyvinyl Alcohol (PVA) (GNPs-CP) nanofibers with excellent mechanical properties. An experimental study was designed to produce nanofibers based on CP nanofibers as matrix and GNPs as reinforcement materials. The microstructure and the surface morphology of the electrospun nanofibers along with their electrical and mechanical properties were examined to study the effect of GNPs content. The SEM results showed that the gradual increase in GNPs content led to a porous web like morphology with no bead. There is a decrease in the diameter of nanofibers by increasing the concentration of GNPs to 1 wt% GNPs from 370 ± 40 nm for CP blend to 144 ± 18 nm for 1 wt% GNPs. Transmission electron microscopy results depicted that GNPs were dispersed uniformly confirmed by the absence of characteristic peak of graphite at 2θ = 26.5°. Attenuated Total Reflectance-Fourier Transform Infrared Spectroscopy results indicate the occurrence of a few interactions between GNPs and CP matrix. Nitrogen adsorption/desorption measurement demonstrated that increasing GNPs content increased the specific surface area of nanofibers from 238.377 to 386.708 m2/g for 0 and 1 wt% GNPs content. The test results also show that the presence of GNPs considerably enhances tensile strength, elastic modulus and electrical conductivity. Furthermore, the toughness of GNPs-CP nanofibers including 1 wt% GNPs significantly improved (12-fold) compared to the one for CP nanofibers. So, the proposed composite provides a decent functionality for nanofibers as scaffolds in tissue engineering applications.


Assuntos
Quitosana , Grafite , Nanofibras , Condutividade Elétrica , Álcool de Polivinil
12.
Chemosphere ; 287(Pt 4): 132385, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34597635

RESUMO

Discharging of inorganic and organic pollutants creates a serious threat to the human health and the environment. In the current work, we have synthesized Ethylenediaminetetraacetic acid (EDTA) functionalized graphene oxide-chitosan nanocomposite (GO-EDTA-CS) for simultaneous removal of inorganic (i.e., mercury (Hg(II) and copper (Cu(II)) and organic pollutants (i.e., methylene blue (MB) and crystal violet (CV)) from wastewater via adsorption process. The structural, functional, morphological, elemental compositions, surface area and thermal properties of the synthesized nanocomposite were identified using powder X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), field scanning electron microscopy (FESEM), energy dispersive spectroscopy (EDS), Brunauer-Emmett-Teller (BET), and thermogravimetric analyzer (TGA), respectively. Different batch adsorption experiments such as pH effect, contact time, initial pollutants concentration, reusability etc. were studied in monocomponent system to optimize the results. The adsorption process apparently followed pseudo-second-order (PSO) kinetics for both pollutants, however the adsorption kinetics was also explained by the intra-particle diffusion model. The isotherm data for both metals ions and dyes were well fit by the Langmuir isotherm model. The maximum adsorption capacities of the adsorbent were determined 324 ± 3.30 130 ± 2.80, 141 ± 6.60, and 121 ± 3.50 mg g-1 for Hg(II), Cu(II), MB, and CV, respectively. The excellent adsorption capacity was attributed to the availability of various active functional groups (e.g., -COOH, -OH, -NH2, etc.) on the adsorbent. The EDS, elemental mapping and FTIR analysis performed before and after the adsorption of heavy metals and dyes by GO-EDTA-CS confirmed the simultaneous adsorption of the pollutants. Moreover, GO-EDTA-CS could maintain its adsorption capacity for both inorganic and organic pollutants even after seven cycles of adsorption-desorption, indicating itself a promising adsorbent for practical wastewater treatment containing both inorganic and organic toxic pollutants.


Assuntos
Quitosana , Poluentes Ambientais , Nanocompostos , Poluentes Químicos da Água , Adsorção , Ácido Edético , Grafite , Humanos , Cinética , Espectroscopia de Infravermelho com Transformada de Fourier , Águas Residuárias , Poluentes Químicos da Água/análise
13.
Spectrochim Acta A Mol Biomol Spectrosc ; 266: 120410, 2022 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-34601367

RESUMO

In this work, an environmentally-friendly and cost-effective enzyme mimic was obtained by facile one-pot preparation of chitosan/Cu/Fe (CS/Cu/Fe) composite. This composite exhibited significantly enhanced oxidase-mimicking activity during catalyzing the oxidation of 3, 3', 5, 5'-tetramethylbenzidine (TMB). The CS/Cu/Fe composite was comprehensively characterized and the possible catalytic mechanism was reasonably explored and discussed. Benefiting from the thermal stability and the compatibility with carbohydrate, the CS/Cu/Fe composite was further integrated with agarose hydrogel to fabricate a portable analytical tube containing oxidase mimic. Based on the inhibition of the catalytic oxidation of TMB in the presence of cysteine, as well as the recovery of oxidase-like activity of CS/Cu/Fe due to the specific complexation of cysteine and mercury ion (Hg2+), the rapid colorimetric detection of Hg2+ was successfully carried out in the analytical tube. This colorimetric method showed good linear response to Hg2+ over the range from 40 nM to 8.0 µM with a detection limit of 8.9 nM. The method also revealed high selectivity and satisfactory results in recovery experiments of Hg2+ detection in tap water and lake water. Furthermore, it was found that the effective removal of Hg2+ could be realized in the analytical tube based on efficient Hg2+ adsorption by CS/Cu/Fe composite and agarose hydrogel. This study not only prepared a robust and low-cost enzyme mimic, but also proposed a smart strategy to simultaneously monitor and remove toxic Hg2+ from contaminated water.


Assuntos
Quitosana , Mercúrio , Adsorção , Catálise , Colorimetria
14.
J Environ Manage ; 301: 113850, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34619590

RESUMO

Chitosan is a natural fiber, chemically cellulose-like biopolymer, which is processed from chitin. Its use as a natural polymer is getting more attention because it is non-toxic, renewable, and biocompatible. However, its poor mechanical and thermal strength, particle size, and surface area restrict its industrial use. Consequently, to improve these properties, cellulose and/or inorganic nanoparticles have been used. This review discusses the recent progress of chitosan and cellulose composite materials, their preparation, and their applications in different industrial sectors. It also discusses the modification of chitosan and cellulose composite materials to allow their use on a large scale. Finally, the recent development of chitosan composite materials for drug delivery, food packaging, protective coatings, and wastewater treatment are discussed. The challenges and perspectives for future research are also considered. This review suggests that chitosan and cellulose nano-composite are promising, low-cost products for environmental remediation involving a simple production process.


Assuntos
Quitosana , Nanocompostos , Purificação da Água , Materiais Biocompatíveis , Celulose , Quitina
15.
Food Chem ; 370: 130507, 2022 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-34619605

RESUMO

While the high internal phase emulsions (HIPEs) have been formed by food-grade biopolymers and granules have been widely reported, it is not known which components are more effective. In this work, we first used heat-treated lactoferrin (LF)-carboxymethyl chitosan (CMCTS) granules and native LF-CMCTS physical mixtures as emulsifiers to form HIPEs. The results showed that the interfacial behavior and emulsifying properties of the two complexes were controlled by the ratio of LF-CMCTS and the optimal ratio of LF to CMCTS was 1:1. Heated LF-CMCTS granules anchored to the water-oil interface and formed an elastic shell to stabilize HIPEs, while unheated LF-CMCTS complexes formed a thick film layer to stabilize HIPEs. Both HIPEs could act as delivery systems loaded with curcumin, and they showed better protection of curcumin than Tween-80 under light. This study provides a new basis for the design of LF-based HIPEs systems loaded with lipophilic food functional ingredients.


Assuntos
Quitosana , Lactoferrina , Emulsões , Temperatura Alta , Tamanho da Partícula
16.
Food Chem ; 372: 131266, 2022 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-34628117

RESUMO

The food-derived peptides hydrolyzed from native food protein matrix exhibited various bioactivities and multimeric structures, which make them the promising well-defined nanoplatforms candidates to co-deliver themselves with other bioactive compounds. In this study, zein-egg white derived peptides-chitosan (Z-EWDP-CS) ternary nanoparticles (NPs) were successfully fabricated by the spontaneous assembly to enhance the stability and bioactivity of curcumin (Cur). The novel ternary NPs exhibited a typical nano-spherical structure (138.63 nm, 40.50 mV), and adorable encapsulation efficiency (EE, 93.87%) for Cur. FTIR, XRD and DSC results verified that Cur changed from a crystalline state to an amorphous state, and was successfully entrapped in the cavity of Z-EWDP-CS NPs. Furthermore, the thermal stability, photochemical stability, salt stability, and antioxidant activity were considerably improved in the NPs after the addition of EWDP. Our results demonstrate that the food-derived peptides could be an ideal affinity agent for the co-delivery of themselves with hydrophobic nutraceuticals.


Assuntos
Quitosana , Curcumina , Nanopartículas , Zeína , Clara de Ovo , Tamanho da Partícula , Peptídeos
17.
Food Chem ; 372: 131221, 2022 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-34649029

RESUMO

The direct incorporation of essential oils (EOs) into real food system faces numerous challenges due to high volatility, intense aroma, and instability. This research aimed to enhance the stability and bio-efficacy of Pimenta dioica essential oil (PDEO) through encapsulation in chitosan (CN) nanoemulsion. The nanoemulsion (CN-PDEO) was fabricated through ionic-gelation technique. CN-PDEO exhibited high nanoencapsulation efficiency (85.84%) and loading capacity (8.26%) with the particle size ranging between 18.53 and 70.56 nm. Bio-efficacy assessment results showed that CN-PDEO presented more effective antifungal and antiaflatoxigenic activity against Aspergillus flavus (AF-LHP-VS8) at lower doses (1.6 and 1.0 µL/mL) than the pure PDEO (2.5 and 1.5 µL/mL, respectively, p < 0.05). Additionally, CN-PDEO preserved model food (maize) from aflatoxin B1and lipid peroxidation without altering their sensory properties during storage with high safety profile (p < 0.05). Overall results concluded that CN-PDEO can be recommended for shelf-life extension of stored maize and other food commodities.


Assuntos
Quitosana , Óleos Voláteis , Aflatoxina B1 , Antifúngicos , Aspergillus flavus , Zea mays
18.
Food Chem ; 372: 131358, 2022 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-34655826

RESUMO

To improve the survivability of Lactobacillus rhamnosus probiotics, nanoliposomes (NLs) coated with chitosan (CH)-gelatin (GE) polyelectrolytes have been synthesized and characterized. The produced CH-GE-coated NLs containing L. rhamnosus had mean sizes in the range of 134.8-495.8 nm. HRTEM showed the smooth spherical shape of the vesicles. ATR-FTIR findings indicated the successful coating of the produced NLs by the used CH-GE polyelectrolytes. According to DSC results, CH-GE polyelectrolytes desorption on the surface of NLs altered the physical characteristics of the phospholipid bilayers. Here, an increase in the melting temperature (Tm) from 119.9 to 127.5 °C in L. rhamnosus-loaded CH-GE-coated NLs made this system more stable than uncoated liposomes. Furthermore, the CH-GE coated nanoparticles loaded with L. rhamnosus exhibited a significant enhancement in the viability of cells under simulated gastrointestinal fluids (SGF/SIF). These results may guide the potential application of polyelectrolytes-coated NLs as a carrier of probiotic cells in functional food development.


Assuntos
Quitosana , Lactobacillus rhamnosus , Nanopartículas , Probióticos , Lipossomos , Polieletrólitos
19.
Food Chem ; 372: 131343, 2022 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-34656910

RESUMO

Stilbene-glycoside (THSG) is a promising dietary supplement with remarkable biological properties, however, its poor stability and low oral bioavailability hinder its application as an ingredient in functional foods. Herein, stilbene-glycoside-loaded nanoparticles (THSG-NPs) coated with carboxymethyl chitosan (CMC) and chitosan hydrochloride (CHC) using a complex coacervation method were successfully prepared for enhancing the stability of THSG. The optimized preparation parameters were 2.5 mg/mL CMC, 1.0 mg/mL CHC, 1.5 mg/mL THSG and preparation temperature of 25 °C, under which the experimentally designed particles averaged 381.9 nm with encapsulation efficiency (EE) of 68.6%. Solid-state characterization was assessed by Fourier transform infrared spectroscope and Differential scanning calorimetry. THSG-NPs showed significant protective effects against heat and solar radiation and exhibited remarkable pH-dependent and controlled release. This work demonstrated that enhanced stability and delayed release of THSG could be achieved using THSG-NPs, which could contribute to its potential application in the functional foods industry.


Assuntos
Quitosana , Nanopartículas , Estilbenos , Portadores de Fármacos , Glicosídeos , Tamanho da Partícula
20.
Food Chem ; 370: 131376, 2022 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-34662793

RESUMO

Mangiferin (MGF), from Mangifera indica is well reported for its hypoglycemic activity and hypolipidemic activity. However, MGF suffers therapeutic limitation due to poor solubility causing disparaging bioavailability. Herein to address this problem, we have incorporated MGF in alginate grafted N-succinylated chitosan (NSC) nanomatrix. Characterization by molecular docking, FT-IR and 2D-NMR (COSY) has revealed that MGF could reinforce interaction with NSC. The OH and CH2OH groups of MGF may set interactions with pyranosic OH, CH2OH, NH2 (or NH-succinyl and COOH-succinyl) of NSC. The NSC-MGF nanoconjugate revealed a spherical particle geometry of 100 âˆ¼ 200 nm size. The encapsulated MGF showed 100% release in vitro. In vivo, NSC-MGF nanoconjugate revealed blood glucose lowering from 300 mg/dL to âˆ¼ 90 mg/dL as well as âˆ¼ 37% lowering of total plasma cholesterol. This is well comparative to the earlier reports which acknowledged only 1 âˆ¼ 36% lowering of plasma cholesterol with MGF. Furthermore, NSC-MGF lowered serum trigyceride to âˆ¼ 61%, while in earlier studies, only 10 âˆ¼ 40% serum triglycerides reduction was found with solitary MGF.


Assuntos
Aterosclerose , Quitosana , Diabetes Mellitus , Hiperlipidemias , Nanopartículas , Alginatos , Animais , Hiperlipidemias/tratamento farmacológico , Simulação de Acoplamento Molecular , Nanoconjugados , Tamanho da Partícula , Ratos , Espectroscopia de Infravermelho com Transformada de Fourier , Xantonas
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