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1.
Gene ; 850: 146955, 2023 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-36220447

RESUMO

The present research aims to evaluate the effect of swimming exercise and chitosan-coated l-arginine on mitochondrial oxidation, BCL2 Interacting Protein 3 (Bnip3), NIP-like protein × (Nix), B-cell lymphoma-extra-large (Bcl-xL) and autophagy-related protein light chain 3(LC3) expression in soleus muscle of aging rats. In this experimental research, 25 male Wistar rats were assigned into five groups randomly: young, old, old + Nano l-arginine (Nano L-a), old + exercise (Ex), and old + Nano l-arginine (Nano L-a) + exercise (Ex) (n = 5 in each). They performed a swimming exercise program five days a week for six weeks. To determine the relative strength for rats before and after performing these interventions, the 1repetition maximum (1RM) test was done as a pre and post-test. The exercise program started with 20 min and after four sessions, gradually increased to 60 min and this time was maintained until the completion of the training period. l-arginine coated with chitosan nanoparticles was given to the rats in the l-arginine-supplemented group via gavage at a dosage of 500 mg/kg/day, five days a week, for six weeks. Additionally, the rats in all groups were fed a normal diet (2.87 kcal/g and 15 % energy from fat). Upon the completion of the protocol implementation, the rats were sacrificed and the soleus muscle was fixed and frozen to determine hematoxylin and eosin (H&E) staining, immunohistochemistry (IHC), gene expression analysis, levels of reactive oxygen species (ROS), and total antioxidant capacity (TAC). The results from the present research indicated that swimming exercise and Nano l-arginine improve the strength and histology of muscle tissue in old rats (p < 0.05). Aging significantly increased the expression of Nix and Bnip3 (p < 0.05) and reduced the Bcl-xL gene expression (p < 0.05). The expression of LC3 protein also increased with aging (p < 0.05). Therapeutic interventions, such as combined treatment (old + Nano L-a + Ex) for old animals, reduced the amount of this protein in soleus muscle (p < 0.05). The ROS values also showed a significant reduction only in the old + Nano L-a + Ex group compared to the old group. Moreover, TAC values show a significant decrease in the old and old + Ex groups in comparison to the young group. The use of arginine supplement, especially in nano form, along with swimming exercise seems to reduce the oxidative damage to the elderly muscle tissue, which has a positive effect on the structure and function of the soleus muscle. Since these interventions only had a significant effect on LC3 protein, further studies with more diverse measurement methods for autophagy are suggested.


Assuntos
Quitosana , Condicionamento Físico Animal , Animais , Masculino , Ratos , Envelhecimento/metabolismo , Antioxidantes/farmacologia , Arginina/farmacologia , Arginina/metabolismo , Autofagia , Proteínas Relacionadas à Autofagia/metabolismo , Quitosana/farmacologia , Suplementos Nutricionais , Amarelo de Eosina-(YS)/metabolismo , Amarelo de Eosina-(YS)/farmacologia , Hematoxilina/metabolismo , Hematoxilina/farmacologia , Músculo Esquelético/metabolismo , Estresse Oxidativo , Condicionamento Físico Animal/fisiologia , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Ratos Wistar , Espécies Reativas de Oxigênio/metabolismo , Natação
2.
Carbohydr Polym ; 300: 120237, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36372504

RESUMO

The effects of dietary chitosan (0, 2, 4, 6, 8 and 10 g/kg) on the growth, health condition and disease resistance of golden pompano Trachinotus ovatus were evaluated. Dietary chitosan significantly enhanced weight gain, with the highest observed in fish fed the 6 g/kg chitosan diet. This chitosan level significantly promoted gut health by increasing villus length, lipase and protease activities and intestinal barrier-related genes expression. Meanwhile, dietary 6 g/kg chitosan improved the inflammatory response and anti-oxidative capacity of fish by regulating the expression of genes involved in NF-κB pathway and Nrf2 pathway, respectively. Furthermore, after challenge with Vibrio harveyi for 2 weeks, the survival rate increased significantly when dietary chitosan level was 6 g/kg. Overall, our results indicate that 6 g/kg chitosan is the optimal dose for enhancing growth, health and disease resistance of fish, but excessive chitosan (10 g/kg) weakens its beneficial effects.


Assuntos
Quitosana , Doenças dos Peixes , Perciformes , Vibrioses , Animais , Resistência à Doença , Quitosana/farmacologia , Perciformes/fisiologia , Ração Animal/análise , Doenças dos Peixes/tratamento farmacológico , Suplementos Nutricionais , Dieta , Peixes , Nível de Saúde , Imunidade Inata
3.
Food Chem ; 403: 134292, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36166926

RESUMO

Antimicrobial food grade hydroxybenzaldehyde derivatives were immobilized on the surface of chitosan films by means of reversible Schiff bases. Spectroscopy and elemental analysis evidenced the different ability of the aldehydes to form Schiff bases with chitosan. Chitosan films modified with Schiff bases of aldehydes exerted antimicrobial properties against E. coli under mild acidic environments. The efficacy of the films lied on the reversibility of synthetized imine bonds and release of the aldehydes which was promoted in mildly acid aqueous solutions. Besides acidity, imine bond reversibility depended on the chemical structure of the aldehyde covalently bonded. Films carrying salicylaldehyde presented the highest in vitro antimicrobial performance and thus, they were chosen to evaluate their effectivity in inhibiting E. coli proliferation in freshly-squeezed carrot-orange juice. Films were successfully activated by the acid environment of the juice and reduced the population of the inoculated pathogen. Salicylaldehyde migrated to the juice did not exert toxic effects on Caco-2 cells.


Assuntos
Anti-Infecciosos , Quitosana , Humanos , Bases de Schiff/farmacologia , Bases de Schiff/química , Quitosana/farmacologia , Quitosana/química , Escherichia coli , Células CACO-2 , Aldeídos/farmacologia , Aldeídos/química , Antibacterianos/farmacologia , Antibacterianos/química , Anti-Infecciosos/farmacologia , Concentração de Íons de Hidrogênio
4.
Food Chem ; 403: 134272, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36174341

RESUMO

The essential oil Pickering emulsions stabilized by zein and chitosan nanoparticles (ZCPs) were investigated. ZCP stabilized Pickering emulsions encapsulating citral and/or cinnamaldehyde (ZCP-CT, ZCP-CN, ZCP-CTCN) were constructed as an effective antimicrobial system, and the stability and antifungal properties were evaluated. When the ratio of zein to chitosan was 20:1, the emulsion showed good stability within 15 days and good sustained release ability during 9-day storage experiment. All Pickering emulsions could reduce fungal growth and ochratoxin A production. The ZCP-CN inhibited 62.3 ± 0.5 % Aspergillus westerdijkiae and reduced mycotoxin production by 83.8 ± 1.0 % in corn within 15 days. Meanwhile, the ZCP-CTCN inhibited 58.6 ± 1.0 % Aspergillus carbonarius within 8 days, and the inhibition rate of mycotoxin was up to 99.8 ± 0.3 % in grape. The Pickering emulsions could extend the release time of essential oil and improve the anti-fungal efficiency, which provide new ideas for the development of new food mildew inhibitor.


Assuntos
Quitosana , Nanopartículas , Óleos Voláteis , Zeína , Emulsões , Quitosana/farmacologia , Armazenamento de Alimentos , Óleos Voláteis/farmacologia , Aspergillus , Tamanho da Partícula
5.
AAPS PharmSciTech ; 23(8): 295, 2022 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-36329254

RESUMO

In this study, chitosan nanoparticles (CsNPs) were used as nanocarrier for ultrasonicated ethanolic extract of Rosmarinus officinalis (UEERO) as a new nanoformulation against Eimeria tenella. Herein, CsNPs have been synthesized by ionic gelation method at pH 3 (CsNPs3) and pH 5 (CsNPs5), followed by characterization of morphology, size, polydispersity index (PDI), surface charge, and loading efficiency of UEERO. An in vitro sporulation inhibition assay (10, 5, 2.5, 1.25, 0.62, 0.31, 0.15, 0.07, 0.04, 0.02, and 0.01 mg/ml normal saline solution) against E. tenella was conducted. Results showed that free CsNPs and UEERO-CsNPs3/5 were cubic- and spherical-shaped with positive charge and average size of ~ 150.8 nm (314.4 nm) and 151.7 nm (321.1 nm), respectively. The total loading efficiency using UV-vis spectrophotometer, was 80.05 at pH 5 and 64.39% at pH 3. The in vitro sporulation inhibition assay revealed that UEERO, CsNPs3/5, and UEERO-CsNPs3/5 showed a potential inhibitory effect on sporulation (%), distortion in wall (%), and sporocyst abnormality (%) in a dose-dependent manner. Accordingly, the concentration (10 mg/ml) showed the best efficacy after 24 h in UEERO, free CsNPs, and UEERO-CsNPs. Moreover, UEERO-CsNPs3 and UEERO-CsNPs5 had stopped the sporulation (%) after 72 h. Taken all together, UEERO-CsNPs3 and UEERO-CsNPs5 are best effective against E. tenella in a dose-dependent manner in terms of sporulation (%), distortion in wall (%), and sporocysts abnormality.


Assuntos
Quitosana , Eimeria tenella , Nanopartículas , Rosmarinus , Animais , Eimeria tenella/fisiologia , Galinhas , Oocistos/fisiologia , Quitosana/farmacologia , Etanol , Extratos Vegetais/farmacologia
6.
ACS Appl Bio Mater ; 5(11): 5377-5385, 2022 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-36343279

RESUMO

Regulation of protein activity is important in their applications for biomedicine and therapeutics. Here, an approach for the regulation of protein bioactivity through molecular confinement provided by oligoethylene glycol (OEG)-based dendronized chitosan (DCS) hydrogels is reported. Structural effects on their thermoresponsiveness are investigated. The highly transparent hydrogels are formed from thermoresponsive DCSs through their thermal dehydration and exhibit an intriguing reversible sol-gel transition property when triggered at physiological temperatures. The thermo-gelling behavior and mechanical strength of these hydrogels are investigated, and possible effects from hydrophobicity of the OEG dendrons, grafting rates of the dendrons on the chitosan main chain, and solid content of polymers are examined. These DCS hydrogels are found to have lamellar morphologies and can provide characteristic hydrophobicity microenvironments formed through the crowded OEG dendrons, which show a higher level of confinement to guest proteins. This allows the DCS hydrogels remarkable activity protection capability to proteins. Furthermore, these DCS hydrogels inherit the degradability from chitosan, allowing protein release from these hydrogels through the controllable ways without impairing their activities.


Assuntos
Quitosana , Dendrímeros , Quitosana/farmacologia , Coloides , Hidrogéis , Polímeros
7.
World J Microbiol Biotechnol ; 39(1): 19, 2022 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-36409376

RESUMO

Chitosan (CS) is one of the most abundant biopolymers in nature with superior properties such as biocompatibility, biodegradability, lack of toxicity, antimicrobial activity, acceleration of wound healing, and stimulation of the immune system. In this study, chitosan was extracted from the exoskeletons of beetles (Pimelia payraudi latreille) and then used for the biosynthesis of highly pure MgO NPs and ZnO NPs by a facile greener route. The extracted chitosan exhibited excellent physicochemical properties, including high extraction yield (39%), high degree of deacetylation (90%), low ash content (1%), high fat-binding capacity (366%), and unusual crystallinity index (51%). The MgO NPs and ZnO NPs exhibited a spherical morphology with crystallite sizes of 17 nm and 29 nm, particle sizes of about 20-70 nm and 30-60 nm, and band gap energies of 4.43 and 3.34 eV, respectively. Antibacterial assays showed that the extracted chitosan exhibited high antibacterial activity against Gram-positive and -negative bacteria, while ZnO NPs showed much stronger antibacterial activity against Gram-positive bacteria than against Gram-negative bacteria. For MgO NPs, the antibacterial activity against Gram-positive bacteria was lower than against Gram-negative bacteria. The results suggest that the synthesized MgO NPs and ZnO NPs are excellent antibacterial agents for therapeutic applications.


Assuntos
Quitosana , Besouros , Óxido de Zinco , Animais , Quitosana/farmacologia , Quitosana/química , Óxido de Zinco/farmacologia , Óxido de Zinco/química , Óxido de Magnésio/farmacologia , Antibacterianos/química
8.
Sci Rep ; 12(1): 19869, 2022 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-36400832

RESUMO

Chitosan nanoparticles (CNPs) are promising versatile cationic polymeric nanoparticles, which have received growing interest over last few decades. The biocompatibility, biodegradability, environmental safety and non-toxicity of the chitosan nanoparticles makes it preferred for a wide range of biological applications including agriculture, medical and pharmaceutical fields. In this study, CNPs were biosynthesized by aqueous extract of Eucalyptus globulus Labill fresh leaves as bio-reductant. Box-Behnken design in 29 experimental runs was used for optimization of different factors affecting the production of CNPs. The maximum yield of CNPs was 9.91 mg/mL at pH of 4.5, chitosan concentration of 1%, incubation time of 60 min and temperature of 50 °C. The crystallinity, particle size and morphology of the biosynthesized CNPs were characterized. The CNPs possess a positively charged surface of 31.1 mV. The SEM images of the CNPs confirms the formation of spherical form with smooth surface. The TEM images show CNPs were spherical in shape and their size range was between 6.92 and 10.10 nm. X-ray diffraction indicates the high degree of CNPs crystallinity. FTIR analysis revealed various functional groups of organic compounds including NH, NH2, C-H, C-O, C-N, O-H, C-C, C-OH and C-O-C. The thermogravimetric analysis results revealed that CNPs are thermally stable. The antibacterial activity of CNPs was determined against pathogenic multidrug-resistant bacteria, Acinetobacter baumannii. The diameters of the inhibition zones were 12, 16 and 30 mm using the concentrations of 12.5, 25 and 50 mg/mL; respectively. When compared to previous studies, the biosynthesized CNPs produced using an aqueous extract of fresh Eucalyptus globulus Labill leaves have the smallest particle sizes (with a size range between 6.92 and 10.10 nm). Consequently, it is a promising candidate for a diverse range of medical applications and pharmaceutical industries.


Assuntos
Acinetobacter baumannii , Quitosana , Nanopartículas , Quitosana/farmacologia , Quitosana/química , Nanopartículas/química , Antibacterianos/farmacologia , Antibacterianos/química , Biofilmes
9.
J Infect Dev Ctries ; 16(10): 1602-1606, 2022 10 31.
Artigo em Inglês | MEDLINE | ID: mdl-36332213

RESUMO

INTRODUCTION: This study aimed to compare the bond strength of teeth treated with radiotherapy with two cavity disinfectants (Chlorhexidine gluconate, a chitosan-containing agent). METHODOLOGY: Eighteen newly extracted, non-carious human third molar teeth were used. The teeth were randomly divided into two main groups, treated and/or non-treated with radiotherapy, then separated into three subgroups for disinfectant agent application (CHX, chitosan, control). A total dose of 70.2 Gy was given over 39 days using a linear radiation accelerator for radiotherapy. After applying the cavity disinfectant, the teeth were restored with composite resin to obtain the stick. All bond strength values from sticks were measured using a universal testing machine. The data were analyzed with ANOVA and Chi-square test at a p < 0.05. RESULTS: Among all groups, Group CH, with no radiotherapy application and containing a chitosan-disinfectant agent, showed the highest bond strength (44.7 ± 8.2). In contrast, Group RC with radiotherapy and disinfectant-free showed the lowest bond strength value (29.1 ± 3.5). The highest bond strength values were obtained after applying the chitosan-containing agent in all groups. CONCLUSIONS: Radiotherapy application had a negative effect, while the use of disinfectant agents had a positive effect on the bond strength.


Assuntos
Quitosana , Desinfetantes , Humanos , Desinfetantes/farmacologia , Adesivos Dentinários/química , Adesivos Dentinários/farmacologia , Quitosana/farmacologia , Dentina , Resistência à Tração , Clorexidina/farmacologia
10.
Sci Rep ; 12(1): 19241, 2022 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-36357532

RESUMO

The promising features of most bacterial celluloses (BC) promote the continuous mining for a cost-effective production approach toward wide and sustainable applications. Herein, cantaloupe peels (CP) were successfully implemented for sustainable BC production. Results indicated that the enzymatically hydrolyzed CP supported the maximum BC production of approximately 3.49 g/L when used as a sole fermentation media. The produced BC was fabricated with polyvinyl alcohol (PVA) and chitosan (Ch), and loaded with green synthesized copper oxide nanoparticles (CuO-NPs) to improve its biological activity. The novel composite showed an antimicrobial activity against several human pathogens such as Staphylococcus aureus, Streptococcus mutans, Salmonella typhimurium, Escherichia coli, and Pseudomonas fluorescens. Furthermore, the new composite revealed a significant in vitro anticancer activity against colon (Caco-2), hepatocellular (HepG-2), and breast (MDA) cancer cells, with low IC50 of 0.48, 0.27, and 0.33 mg/mL for the three cell lines, respectively. On the other hand, the new composite was remarkably safe for human skin fibroblast (HSF) with IC50 of 1.08 mg/mL. Interestingly, the composite membranes exhibited lethal effects against all stages of larval instar and pupal stage compared with the control. In this study, we first report the diverse potential applications of BC/PVA/Ch/CuO-NPs composites based on green synthesized CuO-NPs and sustainably produced BC membrane.


Assuntos
Quitosana , Cucumis melo , Nanopartículas Metálicas , Nanopartículas , Humanos , Cobre , Celulose , Células CACO-2 , Escherichia coli , Bactérias , Quitosana/farmacologia , Álcool de Polivinil , Óxidos , Antibacterianos/farmacologia
11.
Molecules ; 27(21)2022 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-36364017

RESUMO

The current work discusses the production and characterization of new biodegradable nanoparticles for biomedical applications based on insect chitosan. Chitosan has numerous features due to the presence of primary amine groups in repeating units, such as antibacterial and anticancer activities. When polyanion tripolyphosphate is added to chitosan, it creates nanoparticles with higher antibacterial activity than the original chitosan. In this study, the ionic gelation technique was used to make wasp chitosan nanoparticles (WCSNPs) in which TEM and FTIR were used to investigate the physicochemical properties of the nanoparticles. In addition, the antibacterial activities of chitosan nanoparticles against extended-spectrum beta-lactamase (ESBL)- and carbapenemase-producing Klebsiella pneumoniae, Escherichia coli, and Pseudomonas aeruginosa were evaluated. The extracted wasp chitosan exhibited high solubility in acetic acid and met all standard criteria of all characterization testes for nanoparticles; the zeta potential indicated stable WCSNPs capable of binding to cellular membrane and increasing the cellular uptake. The produced WCSNPs showed growth inhibition activity against all tested strains, and the bacterial count was lower than the initial count. The inhibition percent of WCSNPs showed that the lowest concentration of WCSNPs was found to be effective against tested strains. WCSNPs' antibacterial activity implies that they could be used as novel, highly effective antibacterial agents in a variety of biological applications requiring antibacterial characteristics.


Assuntos
Quitosana , Nanopartículas , Vespas , Animais , Quitosana/farmacologia , Quitosana/química , Antibacterianos/farmacologia , Antibacterianos/química , Testes de Sensibilidade Microbiana , Egito , Nanopartículas/química , Escherichia coli
12.
Biomolecules ; 12(11)2022 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-36358951

RESUMO

Creation of bio-multifunctional wound dressings with potent hemostatic, antibacterial, anti-inflammatory, and angiogenesis features for bolstering the healing of full-thickness wounds is sought after for clinical applications. We created bio-multifunctional composite sponges by coupling alginate and chitosan with Sargassum pallidum polysaccharides through electrostatic interactions, calcium ion (Ca2+) crosslinking, and lyophilization. Alginate/chitosan (AC) sponges with different concentrations of Sargassum pallidum polysaccharides were obtained and termed AC, ACS-1%, ACS-2.5%, and ACS-5%. ACS-1% and ACS-2.5% sponges exhibited uniform porosity, high water vapor transmission rate, high water absorption, as well as good hemostatic and antibacterial abilities. ACS-2.5% sponges facilitated wound closure and promoted angiogenesis and re-epithelialization in the dermis. These data suggest that ACS sponges containing a certain amount of Sargassum pallidum polysaccharides could be employed for treatment of full-thickness skin wounds.


Assuntos
Quitosana , Hemostáticos , Sargassum , Quitosana/farmacologia , Alginatos/farmacologia , Polissacarídeos/farmacologia , Antibacterianos/farmacologia
13.
Biomolecules ; 12(11)2022 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-36358932

RESUMO

Alginate hydrogel has received great attention in diabetic wound healing. However, the limited tunability of the ionic crosslinking method prevents the delicate management of physical properties in response to diverse wound conditions. We addressed this issue by using a microgel particle (fabricated by zinc ions and coordinated through the complex of carboxymethyl chitosan and aldehyde hyaluronic acid) as a novel crosslinker. Then the cation was introduced as a second crosslinker to create a double crosslinked network. The method leads to the precise regulation of the hydrogel characters, including the biodegradation rate and the controlled release rate of the drug. As a result, the optimized hydrogels facilitated the live-cell infiltration in vitro and boosted the tissue regeneration of diabetic wounds in vivo. The results indicated that the addition of the microgel as a new crosslinker created flexibility during the construction of the alginate hydrogel, adapting for diverse applications during diabetic-induced wound therapy.


Assuntos
Quitosana , Diabetes Mellitus , Microgéis , Humanos , Hidrogéis/farmacologia , Alginatos , Cicatrização , Quitosana/farmacologia , Diabetes Mellitus/tratamento farmacológico
14.
J Appl Biomater Funct Mater ; 20: 22808000221136061, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36346022

RESUMO

The endeavor was to adopt a facile bi-layered approach to fabricate a novel PVA-chitosan-collagen-licorice nanofibrous mat (PCCLNM) with maintaining the spinning parameters and conditions to assess the synergistic antibacterial action of two biopolymers and having properties for repairing tissues. Bonding behavior, morphological orientation, antibacterial activity, and moisture management features of the electrospun nanofibrous mat were investigated using various characterization techniques. The FTIR analysis of the manufactured nanofibrous mat revealed characteristic peaks of licorice, chitosan, collagen, and PVA polymer, confirming the presence of all polymers in the sample. Additionally, a scanning electron microscopy (SEM) image attributes the development of nanofibers with an average diameter for top and bottom sides were 219 and 188 nm respectively. Furthermore, moisture management tests (MMT) confirm PCCLNM's slow absorption and drying capabilities. Apart from that, a disk diffusion method was used to investigate antibacterial activity against the bacteria Staphylococcus aureus (S. aureus), which revealed a strong presence of antibacterial activity with a 20 mm zone of inhibition due to the chemical constituents of licorice and chitosan compound. The developed bio-nanocomposite could have a potential application as wound healing material.


Assuntos
Quitosana , Nanofibras , Nanofibras/química , Quitosana/farmacologia , Quitosana/química , Staphylococcus aureus , Álcool de Polivinil/química , Antibacterianos/química , Extratos Vegetais
15.
Molecules ; 27(21)2022 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-36364302

RESUMO

The papaya industry is mainly impacted by viral diseases, especially papaya ringspot disease (PRSD) caused by papaya ringspot virus (PRSV). So far, research on the interaction between Chitosan, Lentinan and Ningnanmycin on PRSD has not been reported. This research studied the controlled and interactive effect of three biological agents, namely, Chitosan (C), Lentinan (L) and Ningnanmycin (N), on PRSV in papaya, individually and collectively. The changes in disease index, controlled effect, Peroxidase (POD), Polyphenol oxidase (PPO), Superoxide dismutase (SOD), growth and development of plants were observed at the seedling stage, in pots, and at the fruiting stage, in the field. The appearance and nutrient contents of fruits were measured during the fruit stage. The disease index of PRSV, at seedling and fruiting stages, was significantly lower for chitosan, lentinan and ningnanmycin and their interactive effect, compared to a control check treatment. The activity of the defense enzymes could be improved by the three kinds of biological agents and their interactive effect, especially lentinan and ningnanmycin. The chlorophyll content, plant height, stem diameter and fruit quality rose significantly under chitosan, lentinan and ningnanmycin treatments. The interaction of LN could inhibit PRSV disease at the seedling and fruiting stages of papaya, and promote the growth of plants and the quality of fruit at the fruit stage. Hence, this study provides the theoretical foundation for the biological control of papaya ringspot disease.


Assuntos
Carica , Quitosana , Lentinano , Quitosana/farmacologia , Fatores Biológicos , Doenças das Plantas , Alérgenos , Verduras
16.
Int J Nanomedicine ; 17: 5287-5302, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36411767

RESUMO

Background and Purpose: Infections caused by Staphylococcus aureus (S. aureus) colonization in medical implants are resistant to antibiotics due to the formation of bacterial biofilm internal. Baicalein (BA) has been confirmed as an inhibitor of bacterial biofilm with less pronounced effects owing to its poor solubility and absorption. Studies have found that ß-cyclodextrin-grafted chitosan (CD-CS) can improve drug efficiency as a drug carrier. Therefore, this research aims to prepare BA-loaded CD-CS nanoparticles (CD-CS-BA-NPs) for S. aureus biofilm elimination enhancement. Methods: CD-CS-BA-NPs were prepared via the ultrasonic method. The NPs were characterized using the X-ray diffraction (XRD), Thermo gravimetric analyzer (TGA), Transmission electron microscopy (TEM) and Malvern Instrument. The minimum inhibitory concentration (MIC) of the NPs were investigated. The biofilm models in vivo and in vitro were constructed to assess the S. aureus biofilm elimination ability of the NPs. The Confocal laser method (CLSM) and the Live/Dead kit were employed to explore the mechanism of the NPs in promoting biofilm elimination. Results: CD-CS-BA-NPs have an average particle size of 424.5 ± 5.16 nm, a PDI of 0.2 ± 0.02, and a Zeta potential of 46.13 ± 1.62 mV. TEM images revealed that the NPs were spherical with uniform distribution. XRD and TGA analysis verified the formation and the thermal stability of the NPs. The NPs with a MIC of 12.5 ug/mL exhibited a better elimination effect on S. aureus biofilm both in vivo and in vitro. The mechanism study demonstrated that the NPs may permeate into the biofilm more easily, thereby improving the biofilm elimination effect of BA. Conclusion: CD-CS-BA-NPs were successfully prepared with enhanced elimination of S. aureus biofilm, which may serve as a reference for future development of anti-biofilm agents.


Assuntos
Quitosana , Nanopartículas , beta-Ciclodextrinas , Quitosana/farmacologia , Staphylococcus aureus
17.
Mar Drugs ; 20(11)2022 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-36355025

RESUMO

To explore the application of chitosan-gentamicin conjugate (CS-GT) in inhibiting Vibrio parahaemolyticus (V. parahaemolyticus), which is an important pathogen in aquatic animals worldwide, the antimicrobial activity of CS-GT and the effects of a CS-GT dose on the intestine histopathology and intestinal flora of V. parahaemolyticus-infected shrimps were explored. The results showed that CS-GT possessed broad-spectrum antibacterial activity, with minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC) and half inhibitory concentration (IC50) of 20.00 ± 0.01, 75.00 ± 0.02 and 18.72 ± 3.17 µg/mL for V. parahaemolyticus, respectively. Further scanning electron microscope and cell membrane damage analyses displayed that the electrostatic interaction of CS-GT with cell membrane strengthened after CS grafted GT, resulting in leakage of nucleic acid and electrolytes of V. parahaemolyticus. On the other hand, histopathology investigation indicated that high (100 mg/kg) and medium (50 mg/kg) doses of CS-GT could alleviate the injury of a shrimp's intestine caused by V. parahaemolyticus. Further 16S rRNA gene sequencing analysis found high and medium dose of CS-GT could effectively inhabit V. parahaemolyticus invasion and reduce intestinal dysfunction. In conclusion, CS-GT possesses good antibacterial activity and could protect shrimps from pathogenic bacteria infection.


Assuntos
Quitosana , Microbioma Gastrointestinal , Penaeidae , Vibrio parahaemolyticus , Animais , Quitosana/farmacologia , Quitosana/metabolismo , Gentamicinas/farmacologia , RNA Ribossômico 16S/metabolismo , Penaeidae/genética , Antibacterianos/farmacologia , Antibacterianos/metabolismo
18.
PLoS One ; 17(10): e0274455, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36240206

RESUMO

Burns are physically debilitating and potentially fatal injuries. The most common etiology of burn wound infections in the US is methicillin-resistant Staphylococcus aureus (MRSA), which is particularly recalcitrant when biofilms form. The current standard of care, silver sulfadiazine (SSD) is effective in reducing bacterial load, but less effective in improving burn wound healing. New treatments that can manage infection while simultaneously improving healing would provide a benefit in the treatment of burns. Porcine models are frequently used as a model for human wound healing but can be expensive due to the need to separate wounds to avoid cross contamination. The porcine model developed in this study offers the capability to study multiple partial thickness burn wound (PTBW) sites on a single animal with minimal crosstalk to study wound healing, infection, and inflammation. The current study evaluates a wound rinse and a wound gel formulated with a non-toxic, polycationic chitosan derivative that is hypothesized to manage infection while also promoting healing, providing a potential alternate to SSD. Studies in vitro and in this PTBW porcine model compare treatment with the chitosan derivative formulations to SSD. The wound rinse and wound gel are observed to disrupt mature MRSA biofilms in vitro and reduce the MRSA load in vivo when compared to that of the standard of care. In vivo data further show increased re-epithelialization and faster healing in burns treated with wound rinse/gel as compared to SSD. Taken together, the data demonstrate the potential of the wound rinse/gel to significantly enhance healing, promote re-epithelialization, and reduce bacterial burden in infected PTBW using an economical porcine model.


Assuntos
Queimaduras , Quitosana , Staphylococcus aureus Resistente à Meticilina , Lesões dos Tecidos Moles , Infecção dos Ferimentos , Animais , Queimaduras/complicações , Queimaduras/tratamento farmacológico , Quitosana/farmacologia , Quitosana/uso terapêutico , Humanos , Sulfadiazina de Prata/farmacologia , Sulfadiazina de Prata/uso terapêutico , Suínos , Cicatrização , Infecção dos Ferimentos/tratamento farmacológico
19.
Biomed Res Int ; 2022: 8746530, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36246979

RESUMO

Heart failure is currently one of the leading causes of death worldwide, and the inflammatory factors play an important role in its development. Chitosan oligosaccharide (COS), a low-molecular-weight form of chitosan, has many specific biological activities. In this study, COS effects on heart failure were studied for the first time by performing transverse arch constriction (TAC) surgery in mice, as an animal model of heart failure. Our findings revealed that COS administration (in both 40 mg/kg and 80 mg/kg doses) significantly ameliorated TCA-induced left ventricular (LV) hypertrophy as well as the increase in lung and heart weight in mice, while improving TAC-induced LV dysfunction. Both doses effectively attenuated LV cardiomyocyte hypertrophy, while decreasing heart inflammation after heart failure in mice. In conclusion, our results indicated that the supplementation of COS in normal diet might be an effective way to prevent further myocardial tissue damage in patients suffering from heart failure.


Assuntos
Quitosana , Insuficiência Cardíaca , Animais , Anti-Inflamatórios/farmacologia , Quitosana/farmacologia , Modelos Animais de Doenças , Hipertrofia Ventricular Esquerda , Camundongos , Camundongos Endogâmicos C57BL , Miócitos Cardíacos , Oligossacarídeos/farmacologia , Oligossacarídeos/uso terapêutico , Remodelação Ventricular
20.
J Agric Food Chem ; 70(41): 13186-13199, 2022 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-36194761

RESUMO

This study investigated the influence of chitosan oligosaccharides (COSs) on a thioacetamide-induced hepatic encephalopathy (HE) Wistar rat model. COS treatment statistically reduced the false neurotransmitters and blood ammonia in HE rats, along with the suppression of oxidative stress and inflammation. The disbalanced gut microbiota was detected in HE rats by 16S rDNA sequencing, but the abundance alterations of some intestinal bacteria at either the phylum or genus level were at least partly restored by COS treatment. According to metabolomics analysis of rat feces, six metabolism pathways with the greatest response to HE were screened, several of which were remarkably reversed by COS. The altered metabolites might serve as a bridge for the alleviated HE rats treated with COS and the enhanced intestinal bacterial structure. This study provides novel guidance to develop novel food or dietary supplements to improve HE diseases due to the potential beneficial effect of COS on gut-liver axis.


Assuntos
Quitosana , Microbioma Gastrointestinal , Encefalopatia Hepática , Animais , Ratos , Encefalopatia Hepática/tratamento farmacológico , Encefalopatia Hepática/metabolismo , Encefalopatia Hepática/microbiologia , Quitosana/farmacologia , Amônia/farmacologia , Tioacetamida , Ratos Wistar , DNA Ribossômico , Oligossacarídeos/farmacologia
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