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1.
Food Chem ; 349: 129149, 2021 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-33540221

RESUMEN

The effect of nanochitosan coating containing pomegranate peel extract (PPE) at concentrations 0.5, 0.75 and 1% (w/v) on postharvest quality of apricot fruit was studied during storage at 4 °C for 30 days. Nanoemulsions showed significant increase in droplet diameter 275-400 nm, decrease in zeta potential -30-23 mV and viscosity 90-76 mPas-1 with increase in PPE concentration. Results confirmed that apricot fruit treated with chitosan and 1% PPE showed significantly reduced decay percentage, weight loss, effectively retained DPPH radical scavenging activity, ascorbic acid, kept titratable acidity and firmness at high level than untreated fruit. Color attributes showed decrease in L*, a* values and significant increase in b* value. Nanochitosan containing 1% PPE significantly inhibited total psychrophilic bacterial count, yeast and mold count during storage. Our results suggest that chitosan coatings enriched with pomegranate peel extract has the potential to preserve the quality and extend shelf life of apricot.


Asunto(s)
Quitosano/farmacología , Almacenamiento de Alimentos , Frutas/efectos de los fármacos , Nanoestructuras/química , Extractos Vegetales/química , Granada (Fruta)/química , Prunus armeniaca/efectos de los fármacos , Quitosano/química , Emulsiones
2.
Int J Nanomedicine ; 16: 989-1000, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33633447

RESUMEN

Background: Under certain conditions, the physiological repair of connective tissues might fail to restore the original structure and function. Optimized engineered connective tissues (ECTs) with biophysical properties adapted to the target tissue could be used as a substitution therapy. This study aimed to investigate the effect of ECT enforcement by a complex of multiwall carbon nanotubes with chitosan (C-MWCNT) to meet in vivo demands. Materials and Methods: ECTs were constructed from human foreskin fibroblasts (HFF-1) in collagen type I and enriched with the three different percentages 0.025, 0.05 and 0.1% of C-MWCNT. Characterization of the physical properties was performed by biomechanical studies using unidirectional strain. Results: Supplementation with 0.025% C-MWCNT moderately increased the tissue stiffness, reflected by Young's modulus, compared to tissues without C-MWCNT. Supplementation of ECTs with 0.1% C-MWCNT reduced tissue contraction and increased the elasticity and the extensibility, reflected by the yield point and ultimate strain, respectively. Consequently, the ECTs with 0.1% C-MWCNT showed a higher resilience and toughness as control tissues. Fluorescence tissue imaging demonstrated the longitudinal alignment of all cells independent of the condition. Conclusion: Supplementation with C-MWCNT can enhance the biophysical properties of ECTs, which could be advantageous for applications in connective tissue repair.


Asunto(s)
Quitosano/farmacología , Tejido Conectivo/fisiología , Nanotubos de Carbono/química , Ingeniería de Tejidos , Animales , Fenómenos Biomecánicos , Bovinos , Línea Celular , Quitosano/química , Módulo de Elasticidad , Fibroblastos/efectos de los fármacos , Humanos
3.
Cell Prolif ; 54(3): e13004, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33543561

RESUMEN

OBJECTIVES: Endoscopic submucosal dissection (ESD), a preferential approach for early oesophageal neoplasms, inevitably results in oesophageal strictures in patients. Clinical use of glucocorticoids through submucosal injection is beneficial for inhibiting oesophageal stricture following injury; however, it also has limitations, such as dose loss and perforation. Hence, alternatives to glucocorticoid therapy should be developed. METHODS: A novel porous composite scaffold, ChCo-TAMS, composed of chitosan, collagen-I and triamcinolone acetonide (TA) loaded into poly (lactic-co-glycolic) acid (PLGA) microspheres (TAMS), was successfully constructed and subjected to biological testing to ameliorate oesophageal ESD-related stenosis. RESULTS: The synthesized biomaterials displayed unique properties in inhibiting the activation of macrophages, chemokine-mediated cell recruitment and fibrogenesis of fibroblasts. Further application of the scaffolds in the rat dermal defect and porcine oesophageal ESD model showed that these novel scaffolds played a robust role in inhibiting wound contracture and oesophageal ESD strictures. CONCLUSIONS: The developed composite scaffolds provide a promising clinical medical device for the prevention of post-operative oesophageal stricture.


Asunto(s)
Quitosano/farmacología , Colágeno/efectos de los fármacos , Constricción Patológica/patología , Neoplasias Esofágicas/tratamiento farmacológico , Estenosis Esofágica/tratamiento farmacológico , Animales , Materiales Biocompatibles/metabolismo , Quitosano/metabolismo , Colágeno/metabolismo , Constricción Patológica/etiología , Neoplasias Esofágicas/patología , Estenosis Esofágica/prevención & control , Ratones , Microesferas , Triamcinolona/metabolismo , Triamcinolona Acetonida/administración & dosificación , Triamcinolona Acetonida/farmacología
4.
ACS Appl Mater Interfaces ; 13(7): 9143-9155, 2021 Feb 24.
Artículo en Inglés | MEDLINE | ID: mdl-33567821

RESUMEN

Pesticide leaching and soil contamination are major issues in the present agriculture formulations. Hence, here 2D graphene oxide in combination with cationic, anionic, or nonionic polymers were tested for runoff resistance and targeted release behavior. Cationic polymer supplemented the binding of rGO on leaf surface by 30% more than control and reduced off-target leaching in soil by 45% more than control. Further, to enhance the fruit rot control caused by Colletotrichum capsici in chili crop, the rGO was decorated with Cu2-xSe nanocrystals, which provided combined disease control with captan. The chitosan coating in the nanocomposite added targeted pH-responsive fungal inhibition behavior and could reduce the C. capsici growth by ∼1/2 times compared to captan control.


Asunto(s)
Captano/farmacología , Quitosano/farmacología , Colletotrichum/efectos de los fármacos , Fungicidas Industriales/farmacología , Grafito/farmacología , Enfermedades de las Plantas/prevención & control , Captano/química , Quitosano/química , Colletotrichum/crecimiento & desarrollo , Frutas/química , Fungicidas Industriales/química , Grafito/química , Concentración de Iones de Hidrógeno , Pruebas de Sensibilidad Microbiana , Nanocompuestos/química , Tamaño de la Partícula , Propiedades de Superficie
5.
AAPS PharmSciTech ; 22(3): 76, 2021 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-33595780

RESUMEN

Collagen and chitosan have haemostatic, tissue fix and wound healing properties but the poor mechanical property limits their application. Therefore, various concentrations of collagen (1-6%) and chitosan (1-2%) were used to develop biopolymer-coated gauzes, with and without glycerol as plasticiser. Glycerol-treated gauzes showed desired mechanical and adhesive property in comparison to polymer-coated gauzes alone. Developed gauzes were characterized using differential scanning calorimetry, thermal gravimetric analysis and Fourier transform infrared spectrophotometry to confirm the biopolymer coating and stability. Scanning electron microscopy showed multilayer coating of the biopolymer and faster clotting in chitosan gauzes in comparison to collagen. Surface plasmon resonance assay confirmed that chitosan exhibited more binding affinity of 65 RU in comparison to collagen, which showed 55 RU with erythrocytes. Decrease in the value of plateletcrit and mean platelet volume confirmed platelet adhesion and aggregation over the surface of polymer-coated dressings. Gamma scintigraphy studies showed 85 ± 2% formulation retention up to 12 h at the wound site in comparison to 40 ± 3% retention of the radiopharmaceutical alone. Collagen and chitosan-coated gauze showed 226 ± 15 s and 179 ± 12 s haemostasis time, respectively, which was significantly less from 506 ± 15 s in standard gauze. Chitosan gauze showed faster wound healing in comparison to the collagen-coated gauze. Chitosan and collagen-coated gauzes showed 55 ± 4% wound contraction on day seven in comparison to 25 ± 2% in the control group, while chitosan gauzes showed complete wound contraction on day fourteenth, while the collagen-coated gauze showed 90 ± 3% on the same day.


Asunto(s)
Vendajes , Quitosano/farmacología , Colágeno/farmacología , Hemostáticos/farmacología , Cicatrización de Heridas/efectos de los fármacos , Adulto , Animales , Biopolímeros/farmacología , Humanos , Masculino , Ratas , Ratas Sprague-Dawley
6.
Carbohydr Polym ; 256: 117519, 2021 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-33483040

RESUMEN

Vitreous, an essential dioptric medium for the human eyes, must be filled with artificial materials once damaged. Carboxymethyl chitosan (CMCTS) is one of the most important water-soluble chitosan derivatives with improved biocompatibility and biodegradability. In this study, oxidized hyaluronic acid (OHA) was prepared as crosslinking reagent. CMCTS and OHA were used to develop a biocompatible, self-repairing and in-situ injectable hydrogel for vitreous substitutes. Results showed the hydrogel with controllable swelling properties, high transparency, acceptable cytocompatibility on mouse fibroblast L929 and histocompatibility in vivo. Furthermore, hydrogel was injected in-situ into the vitreous cavity after vitrectomy on New Zealand Rabbits, no significant and persistent adverse effects were observed during the 90-day follow-up period. In addition, the hydrogel maintained intraocular pressure of the operated eyes and the inherent position of the retina. Collectively, this injectable, biodegradable, nontoxic hydrogel possessed enormous potential to become a vitreous substitute material.


Asunto(s)
Materiales Biocompatibles/química , Quitosano/análogos & derivados , Ácido Hialurónico/química , Hidrogeles/química , Cuerpo Vítreo/cirugía , Animales , Materiales Biocompatibles/farmacología , Línea Celular , Supervivencia Celular/efectos de los fármacos , Quitosano/química , Quitosano/farmacología , Femenino , Fibroblastos/citología , Fibroblastos/efectos de los fármacos , Humanos , Ácido Hialurónico/farmacología , Hidrogeles/farmacología , Inyecciones Intraoculares , Presión Intraocular/efectos de los fármacos , Presión Intraocular/fisiología , Masculino , Ratones , Conejos , Ratas , Ratas Sprague-Dawley , Solubilidad , Resultado del Tratamiento , Vitrectomía/métodos , Agua/química
7.
ACS Appl Mater Interfaces ; 13(2): 3237-3245, 2021 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-33405504

RESUMEN

Cationic polymers are promising antibacterial agents because bacteria have a low propensity to develop resistance against them, but they usually have low biocompatibility because of their hydrophobic moieties. Herein, we report a new biodegradable and biocompatible chitosan-derived cationic antibacterial polymer, 2,6-diamino chitosan (2,6-DAC). 2,6-DAC shows excellent broad-spectrum antimicrobial activity with minimum inhibitory concentrations (MICs) of 8-32 µg/mL against clinically relevant and multidrug-resistant (MDR) bacteria including Listeria monocytogenes, Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, and Acinetobacter baumannii. Furthermore, 2,6-DAC shows an excellent synergistic effect with various clinically relevant antibiotics proved by decreasing the MICs of the antibiotics against MDR A. baumannii and methicillin-resistant Staphylococcus aureus to <1 µg/mL. In vivo biocompatibility of 2,6-DAC is proved by a dosage of 100 mg/kg compound via oral administration and 25 mg/kg compound via intraperitoneal injection to mice; 2,6-DAC does not cause any weight loss and any significant change in liver and kidney biomarkers or the important blood electrolytes. The combinations of 2,6-DAC together with novobiocin and rifampicin show >2.4 log10 reduction of A. baumannii in murine intraperitoneal and lung infection models. The novel chitosan derivative, 2,6-DAC, can be utilized as a biocompatible broad-spectrum cationic antimicrobial agent alone or in synergistic combination with various antibiotics.


Asunto(s)
Antibacterianos/química , Antibacterianos/farmacología , Bacterias/efectos de los fármacos , Quitosano/análogos & derivados , Quitosano/farmacología , Animales , Infecciones Bacterianas/tratamiento farmacológico , Sinergismo Farmacológico , Femenino , Humanos , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Ratones Endogámicos BALB C , Pruebas de Sensibilidad Microbiana
8.
Food Chem ; 348: 129113, 2021 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-33508609

RESUMEN

The effect of chitosan coating exposure on juice sac granulation and energy metabolism in harvested pummelo fruit was investigated. Pummelo fruits were exposed to 1.5% chitosan coating, and then stored at 20 ± 2 °C for about 150 days. Postharvest chitosan coating treatment apparently alleviated the development of juice sac granulation as well as the increases in weight loss, pulp firmness, cell membrane permeability and cellulose content. The levels of adenosine triphosphate (ATP), adenosine diphosphate (ADP) and energy charge (EC) in the chitosan-coated fruit showed significantly higher levels than those of the respective controls. Meanwhile, the enzymses actively engaged in energy metabolism such as H+-ATPase, Ca2+-ATPase, Mg2+-ATPase, cytochrome C oxidase (CCO), succinate dehydrogenase (SDH) and malate dehydrogenase (MDH) were markedly maintained by chitosan coating. Besides, notably high contents of acetyl-CoA, cis-aconitate, succinate, fumarate and oxaloacetate were observed in the chitosan-coated fruit. The results highlighted that chitosan coating could delay postharvest senescence of pummelo fruit by reducing the rate of energy depletion while maintaining higher levels of key metabolites taking part in tricarboxylic acid (TCA) cycle at room temperature storage.


Asunto(s)
Quitosano/farmacología , Citrus/metabolismo , Metabolismo Energético/efectos de los fármacos , Acetilcoenzima A/metabolismo , Adenosina Difosfato/metabolismo , Adenosina Trifosfatasas/metabolismo , Adenosina Trifosfato/metabolismo , Celulosa/metabolismo , Citrus/química , Frutas/química , Frutas/metabolismo
9.
Int J Food Microbiol ; 341: 109047, 2021 Mar 02.
Artículo en Inglés | MEDLINE | ID: mdl-33515813

RESUMEN

Nowadays, adding biological compounds to food packaging is one of the types of active packaging. The aim of this study was to prepare a new degradable coating with free and nano-encapsulated Cumino cyminum L. essential oil (CCEO) with nanochitosan (Nch) base to evaluate the microbial, chemical and sensory properties of sardine fillet samples for 16 days at 4 °C. Nanoliposome using different soy lecithin ratios and cholesterol concentrations (60:0, 50:10, 40:20, and 30:30) and technique of thin-film hydration-sonication, were prepared with a range of 140-164 nm size. Encapsulation efficiency (EE) and distribution of nanoliposomes size were calculated 0.80-0.90 and 49.85-73.01% respectively. To coat sardine fillet samples, nanoliposomes with the lower size of droplet and higher EE percent were selected. The outcomes indicated that coating treatments can effectively inhibit microbial growth and chemical spoilage reflected at lower pH, peroxide value (PV) and thiobarbituric acid reactive substances (TBARs) (P < 0.05). In fact, the results of chemical and microbiological characteristics showed that the samples treated with nanocitosan/nano essential oil (NEO) showed the lowest value among other treatments during the experimental period, in the following, Nch-EO, Nch and control. pH, PV, TBARs, total viable counts (TVC), total pseudomonads count (TPC), and lactic acid bacteria (LAB) were 6.85, 0.03 (mg MDA/kg), 5.23 (mEq/kg), 3.67 (CFU/g), 3.47 (CFU/g), and 4.7 (CFU/g), respectively for Nch-NEO at the end of storage time. In addition, during the experimental period, the highest sensory properties were obtained for the Nch-NEO group. Encapsulation of CCEO reduces the rate of diffusion, thus increasing antimicrobial and antioxidant activity, as well as improving sensory properties. According to the results of this study, CCEO-encapsulated nanochitosan coatings can be used as a potent coating to increase sardine shelf life.


Asunto(s)
Antibacterianos/farmacología , Quitosano/farmacología , Cuminum/química , Embalaje de Alimentos/métodos , Aceites Volátiles/farmacología , Alimentos Marinos/microbiología , Animales , Antioxidantes/química , Antioxidantes/farmacología , Carga Bacteriana/efectos de los fármacos , Quitosano/química , Colesterol/farmacología , Peces/microbiología , Conservación de Alimentos/métodos , Almacenamiento de Alimentos/métodos , Lecitinas/farmacología
10.
J Sci Food Agric ; 101(1): 229-239, 2021 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-32627181

RESUMEN

BACKGROUND: Synthetic fungicides are most commonly used for controlling postharvest disease of fruit, although they can cause the emergence of drug-resistant strains, environmental pollution and fruit safety issues. Bacillomycin D (BD), a novel antifungal lipopeptide, and chitosan (CTS) are applied for the preservation of cherry tomato. RESULTS: The combination of BD and CTS showed an additive inhibition on the growth of Rhizopus stolonifer and Botrytis cinerea compared to that of its individual compound. In addition, BD + CTS reduced the incidence of soft rot and gray mold in cherry tomato caused by R. stolonifer and B. cinerea, respectively. Tomato treated with BD + CTS exhibited a lower weight loss and higher firmness and higher contents of total soluble solids, titratable acidity and ascorbic acid compared to those treated with sterile water (control). The kinetics models demonstrated that the shelf life of cherry tomato treated with BD + CTS could be extended by approximately 15 days longer than the control. CONCLUSION: The utilization of BD + CTS provided a novel strategy for reducing postharvest fungal rot and maintaining the storage quality of cherry tomato. © 2020 Society of Chemical Industry.


Asunto(s)
Péptidos Catiónicos Antimicrobianos/farmacología , Botrytis/efectos de los fármacos , Quitosano/farmacología , Conservación de Alimentos/métodos , Fungicidas Industriales/farmacología , Lycopersicon esculentum/microbiología , Rhizopus/efectos de los fármacos , Botrytis/crecimiento & desarrollo , Sinergismo Farmacológico , Frutas/química , Frutas/microbiología , Lycopersicon esculentum/química , Enfermedades de las Plantas/microbiología , Rhizopus/crecimiento & desarrollo
11.
Food Chem ; 336: 127636, 2021 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-32805513

RESUMEN

Deposition of both lignin and cellulose accompanied by juice sac granulation is widespread in harvested citrus fruit. Hence, measures to suppress postharvest granulation of 'Majiayou' pummelo is of great importance. The fruit was treated with 1.5% chitosan and then stored at room temperature (20 ± 2 °C) for 150 d. As compared to the control fruits, chitosan coating significantly suppressed granulation index and maintained good quality. Chitosan coating inhibited lignification by suppressing the activities and expression levels of lignin synthesis-related enzymes (PAL, CAD and POD). By contrast, chitosan treatment enhanced the activities and expression levels of cell wall degrading enzymes, including PME, PG, Cx, XTH and ß-Gal, which might contribute to the decrease in cellulose. In a nutshell, chitosan coating can effectively suppress juice sac granulation and fruit senescence of pummelo fruits, and play a crucial role in maintaining the cell wall modification.


Asunto(s)
Pared Celular/efectos de los fármacos , Quitosano/farmacología , Citrus/efectos de los fármacos , Almacenamiento de Alimentos , Frutas/efectos de los fármacos , Pared Celular/química , Pared Celular/metabolismo , Celulosa/metabolismo , Citrus/metabolismo , Enzimas/genética , Enzimas/metabolismo , Conservantes de Alimentos/farmacología , Frutas/metabolismo , Regulación de la Expresión Génica de las Plantas/efectos de los fármacos , Lignina/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Análisis de Componente Principal , Temperatura
12.
Plant Physiol Biochem ; 159: 53-66, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33338820

RESUMEN

We report a novel chitosan-silicon nanofertilizer (CS-Si NF) wherein chitosan-tripolyphosphate (TPP) nano-matrix has been used to encapsulate silicon (Si) for its slow release. It was synthesied by ionic gelation method and characterized by dynamic light scattering (DLS), fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), scanning electron microscopy (SEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and atomic absorption spectrophotometry (AAS). The developed CS-Si NF exhibited slow release of Si and promoted gowth and yield in maize crop. Seeds primed with different concentrations of CS-Si NF (0.04-0.12%, w/v) exhibited up to 3.7 fold increased seedling vigour index (SVI) as compared with SiO2. Its foliar spray significantly induced antioxidant-defence enzymes' activities and equilibrated cellular redox homeostasis by balancing O2-1 and H2O2 content in leaf as compared with SiO2. Application of nanofertilizer (0.01-0.16%, w/v) stirred total chlorophyll content (21.01-25.11 mg/g) and leaf area (159.34-166.96 cm2) to expedite photosynthesis as compared with SiO2. In field experiment, 0.08% CS-Si NF resulted in 43.4% higher yield/plot and 0.04% concentration gave 45% higher test weight as compared with SiO2. Fecund and myriad effects of developed nanofertilizer over SiO2 could be attributed to slow/protective release of Si from nanofertilizer. Overall, results decipher the enormous potential of CS-Si NF for its use as a next generation nanofertilizer for sustainable agriculture.


Asunto(s)
Agricultura , Quitosano , Dióxido de Silicio , Zea mays , Agricultura/métodos , Quitosano/farmacología , Fertilizantes/normas , Peróxido de Hidrógeno/metabolismo , Dióxido de Silicio/farmacología , Espectroscopía Infrarroja por Transformada de Fourier , Zea mays/efectos de los fármacos
13.
Food Chem ; 337: 127772, 2021 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-32777571

RESUMEN

Chitosan can function a key role in plant resistant against Botrytis cinerea infection, while its mechanism is unclear in ripened fruits. In this study, we investigated the chitosan effect on two type of ripened fruits including strawberry and grapes (Kyoho and Shine-Muscat) when were infected with B. cinerea. Results showed that chitosan inhibited B. cinerea growth, increased phenolic compounds and cell wall composition, modulated oxidative stress and induced jasmonic acid (JA) production in ripened fruits. Data-independent acquisition (DIA) showed that 224 and 171 proteins were upregulated 1.5-fold by chitosan in Kyoho and Shine-Muscat grape, respectively. Topless-related protein 3 (TPR3) were identified and interacted with histone deacetylase 19 (HDAC19) and negatively regulated by JA and chitosan. Meanwhile, overexpression of VvTPR3 and VvHDAC19 reduced the stability of cell wall against B. cinerea in strawberry. Taken together, chitosan induces defense related genes and protect the fruit quality against Botrytis infection through JA signaling.


Asunto(s)
Botrytis/efectos de los fármacos , Quitosano/farmacología , Ciclopentanos/metabolismo , Fragaria/metabolismo , Oxilipinas/metabolismo , Vitis/metabolismo , Botrytis/fisiología , Pared Celular/metabolismo , Fragaria/microbiología , Frutas/metabolismo , Frutas/microbiología , Histona Desacetilasas/genética , Histona Desacetilasas/metabolismo , Enfermedades de las Plantas/genética , Enfermedades de las Plantas/microbiología , Proteínas de Plantas/antagonistas & inhibidores , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Interferencia de ARN , Esporas Fúngicas/efectos de los fármacos , Regulación hacia Arriba/efectos de los fármacos , Vitis/microbiología
14.
Food Chem ; 337: 127745, 2021 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-32795855

RESUMEN

Microalgae are a precious source of polyunsaturated fatty acids (PUFA), however extraction is difficult due to the peculiar microalgae cell structure. Here we describe a new method based on the application of chitosan nanoaggregates as CO2 responsive emulsifier, used to promote the swelling of algae cell wall and the formation of a large oil - ethanol interphase area during the ethanolysis. Tests were carried out with Pseudokirchneriella subcapitata and Nannochloropsis sp. at different biomass/ethanol/chitosan ratios. CO2 was added to trigger demulsification to promote an easy recovery of the lipid fraction. The highest yields in PUFA were obtained with Nannochloropsis sp. (207.9 mg/g of oil) using 0.4% wt of chitosan and 1:10 biomass:ethanol ratio; 43.6 mg/g of linolenic acid were obtained from Pseudokirchneriella subcapitata. Overall, because the method employs ethanol, a generally recognized as safe (GRAS) solvent, and food grade additives, it is suited for the preparation of PUFA supplements.


Asunto(s)
Quitosano/farmacología , Ácidos Grasos Omega-3/metabolismo , Microalgas/efectos de los fármacos , Microalgas/metabolismo , Biomasa , Suplementos Dietéticos , Esterificación/efectos de los fármacos , Etanol/farmacología
15.
PLoS One ; 15(12): e0244301, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33338083

RESUMEN

Adhesion and scarring after neural surgery are detrimental to nerve regeneration and functional recovery. Amniotic membranes have been used in tissue repair due to their immunogenicity and richness in cytokines. In this study, an electrospun polycaprolactone (PCL)-amnion nanofibrous membrane was prepared for the treatment of sciatic nerve compression in a rat model. The effects of the PCL-amnion nanofibrous membrane on the prevention of adhesion formation and nerve regeneration were evaluated using electrophysiology and histological analyses. Compared with the medical chitosan hydrogel dressing, the PCL-amnion nanofibrous membrane significantly reduced peripheral nerve adhesion and promoted the rapid recovery of nerve conduction. Moreover, the immunohistochemical analysis identified more Schwann cells and less pro-inflammatory M1 macrophages in the PCL-amnion group. Western blot and RT-PCR results showed that the expression levels of type-Ⅰ and Ⅲ collagen in the PCL-treated rats were half of those in the control group after 12 weeks, while the expression level of nerve growth factor was approximately 3.5 times that found in the rats treated with medical chitosan hydrogel. In summary, electrospun PCL-amnion nanofibrous membranes can effectively reduce adhesion after neural surgery and promote nerve repair and regeneration. The long-term retention in vivo and sustained release of cytokines make PCL-amnion a promising biomaterial for clinical application.


Asunto(s)
Regeneración Nerviosa/efectos de los fármacos , Poliésteres/farmacología , Adherencias Tisulares/prevención & control , Amnios/patología , Animales , Materiales Biocompatibles , Quitosano/farmacología , Colágeno/farmacología , Modelos Animales de Enfermedad , Hidrogeles/farmacología , Masculino , Nanofibras/química , Ratas , Ratas Sprague-Dawley , Células de Schwann/patología , Nervio Ciático/patología , Neuropatía Ciática/fisiopatología , Adherencias Tisulares/tratamiento farmacológico , Ingeniería de Tejidos/métodos , Andamios del Tejido
16.
An Acad Bras Cienc ; 92(4): e20200562, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33237148

RESUMEN

Periodontal disease is considered the main oral cavity disorder in dogs. Essential oils have the potential for use in the prevention and treatment of oral diseases. The antimicrobial activity of Schinus molle L. essential oil (SMEO) has already been reported. Chitosan, a natural product with antimicrobial activity and good biocompatibility has potential in biodental applications. In this study, we evaluated the in vitro antimicrobial activity of SMEO against bacteria associated with periodontal disease in dogs, developed and evaluated the physicochemical properties of a novel chitosan-based buccal delivery system containing SMEO. SMEO showed antimicrobial activity against Gram positive and Gram negative bacteria associated with canine periodontitis, with MIC values of 750 µg.mL-1 for Staphylococcus spp. and Streptococcus spp, 1000 µg.mL-1 for Corynebacterium spp. and 1250 µg.mL-1 for Pseudomonas spp. All formulations evaluated presented adequate physicochemical properties, good stability, and pH values close to buccal pH (5.0-7.0). Chitosan gel loaded with SMEO showed potential as a SMEO delivery system, having the ideal physicochemical and rheological properties (pseudoplastic and apparent viscosities) required for application on buccal tissue. Thus, we can conclude that formulation has the potential to be used for buccal mucosa delivery in the prevention and treatment of periodontal disease in dogs.


Asunto(s)
Anacardiaceae , Quitosano , Aceites Volátiles , Animales , Antibacterianos , Quitosano/farmacología , Perros , Geles , Bacterias Gramnegativas , Bacterias Grampositivas , Aceites Volátiles/farmacología
17.
PLoS One ; 15(10): e0239993, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33022025

RESUMEN

A two-year field trial was conducted in a vineyard (northern Egypt)cultivated with Thompson seedless grapevines to evaluate the effectiveness of four "alternative" (biological/chemical) treatments, Bacillus megaterium, boric acid, calcium nitrate and chitosan, against the root-knot nematode Meloidogyne incognita (Mi), compared to that of the nematicide oxamyl. The influence of these treatments on plant nutritional status and fruit yield and quality was also assessed. All treatments significantly inhibited Mi reproduction parameters in both seasons, decreasing the numbers of nematode galls and egg masses (roots) and of second-stage juveniles (soil). Oxamyl application resulted in the highest reductions in Mi-reproduction parameters, followed by boric acid, which also showed the highest relative nematicidal efficacy (respect to oxamyl). In the 1st season, the highest fruit yield (10.34 kg/grapevine) was recorded from boric acid-treated plants, followed by that from oxamyl-treated plants (7.50 kg/grapevine); in the subsequent season (2019), oxamyl use led to the highest yield, followed by boric acid + chitosan use (10.04 and 8.62 kg/grapevine, respectively). In both seasons, application of boric acid alone and combined with chitosan enhanced the total soluble solids (TSS)/total acidity ratio in grape juice. All treatments led to higher nutrient contents (leaf petioles) and chlorophyll levels (leaves) as well as enhanced fruit size and weight. We conclude that the tested treatments can be safely applied for nematode management in Thompson seedless grapevines, with positive effects on fruit yield and quality.


Asunto(s)
Estado Nutricional , Regulación de la Población/métodos , Tylenchoidea/fisiología , Vitis/crecimiento & desarrollo , Animales , Antinematodos/farmacología , Ácidos Bóricos/farmacología , Carbamatos/farmacología , Quitosano/farmacología , Clorofila/análisis , Egipto , Frutas/efectos de los fármacos , Frutas/crecimiento & desarrollo , Frutas/metabolismo , Jugos de Frutas y Vegetales/análisis , Estado Nutricional/efectos de los fármacos , Estaciones del Año , Tylenchoidea/efectos de los fármacos , Vitis/efectos de los fármacos , Vitis/metabolismo
18.
Indian J Dent Res ; 31(4): 550-556, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33107455

RESUMEN

Background: The complex structure and irregularities of root canal walls are liable for infection by several bacterial species. Thus, the use of irrigants and auxiliary chemical solutions associated with instrumentation is necessary for effective eradication of the biofilm as well as complete removal of the smear layer. Aim: To evaluate the effects of calcium hypochlorite and chitosan oligosaccharide (COS) in disinfecting Enterococcus faecalis root canal biofilm and smear layer removal with minimal erosion. Materials And Methods: A total of 70 mandibular premolars were decoronated at the cementoenamel junction. The samples were biomechanically prepared, sterilized in an autoclave, and incubated with E. faecalis (ATCC-29212) bacteria for 21 days. Cleaning and shaping were done till maximum apical file size of #45 K. Specimens were randomly divided into 4 groups: GROUP I: Control Group, GROUP II: 5% Sodium Hypochlorite (NaOCl) solution followed by 17% EDTA solution, GROUP III: 5% Calcium Hypochlorite [Ca(OCl)2] solution followed by 17% EDTA solution and GROUP IV: 5% Ca(OCl)2 solution followed by 1% COS. The samples were subjected to microbial count followed by smear layer removal under scanning electron microscope (SEM) at coronal, middle and apical third. Statistical Analysis Used: Kruskal-Wallis Test and post-hoc Scheffe's test. Results: It was observed that Group IV showed the lowest amount of CFU count/mL and the highest amount of smear layer removal with a statistically significant difference (P < 0.05) when compared with the other three Groups. Conclusion: 5% Ca(OCl)2 solution with 1% COS solution effectively removed the Enterococcus faecalis biofilm and smear layer from the root canals with minimal erosion.


Asunto(s)
Quitosano , Capa de Barro Dentinario , Biopelículas , Compuestos de Calcio , Quitosano/farmacología , Ácido Edético , Humanos , Microscopía Electrónica de Rastreo , Oligosacáridos , Irrigantes del Conducto Radicular/farmacología , Preparación del Conducto Radicular
19.
Int J Nanomedicine ; 15: 7877-7887, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33116506

RESUMEN

Purpose: The emergence of Neisseria gonorrhoeae strains that are resistant to the most commonly used antibiotics represents a great concern for global public health. This challenges the effectiveness of clinical treatment regimens and demands the development of alternative antigonococcal agent. In this regard, chitosan nanoparticles (CNPs) are known to have antimicrobial activity against a wide range of pathogens. Thus, they have become a potential candidate for combatting this era of multi-drug resistance. This study aims to formulate CNPs, characterize their physicochemical properties, and examine their antimicrobial activity against gonococcus. Materials and Methods: The ionic gelation method was used to prepare CNPs of different concentrations. Characterization for their particle size (PZ), polydispersity index (PDI), and zeta potential (ZP) was performed. The anti-microbial activity of CNPs was investigated against 13 WHO N. gonorrhoeae reference strains, using the broth dilution method. Cytotoxicity of CNPs and their effect on bacterial adhesion to HeLa cells were investigated. Results: The average PZ and ZP of the prepared NPs were increased when the concentration of chitosan was increased from 1 to 5 mg/mL and found to be in the range of 193 nm ± 1.9 to 530 nm ± 13.3, and 14 mV ± 0.5 to 20 mV ± 1, respectively. Transmission electron microscopes (TEM) images revealed spherical NPs, and the NPs had a low PDI value of ≤0.27. The formed CNPs produced antibacterial activity against all tested strains, including those resistant to multiple antibiotics, with a minimum inhibitory concentration (MIC90) of 0.16 to 0.31 mg/mL and a minimum bactericidal concentration (MBC) of 0.31 to 0.61 mg/mL. Of note, at all MIC90 and MBC, the CNPs had no significant cytotoxic effect on HeLa cells and reduced bacterial adhesion to these cells at MBC doses. Conclusion: The present work findings suggest the potential of the CNPs for the treatment of gonorrhoea.


Asunto(s)
Antibacterianos/química , Antibacterianos/farmacología , Quitosano/química , Quitosano/farmacología , Nanopartículas/química , Neisseria gonorrhoeae/efectos de los fármacos , Antibacterianos/toxicidad , Adhesión Bacteriana/efectos de los fármacos , Quitosano/toxicidad , Células HeLa , Humanos , Pruebas de Sensibilidad Microbiana , Neisseria gonorrhoeae/fisiología , Tamaño de la Partícula
20.
Int J Food Microbiol ; 334: 108838, 2020 Dec 02.
Artículo en Inglés | MEDLINE | ID: mdl-32896745

RESUMEN

White brined cheese may serve as an ideal medium for the growth of foodborne pathogens including E. coli O157:H7. The objectives of this study were i) to evaluate the inhibitory effects of zinc oxide (ZnO) nanoparticles against E. coli O157:H7 at 10 or 37 °C using broth dilution; ii) to address the post-process contamination of white brined cheese with E. coli O157:H7 by using chitosan coating with or without ZnO nanoparticles during storage for 28 d at 4 and 10 °C; and iii) to study the physicochemical characteristics of chitosan coating containing ZnO nanoparticles. ZnO nanoparticles at ≥0.0125% inhibited the growth of three E. coli O157:H7 strains at both 37 and 10 °C. The chitosan coating with or without ZnO nanoparticles significantly reduced the initial numbers of E. coli O157:H7 in white brined cheese by 2.5 and 2.8 log CFU/g, respectively, when stored at 4 °C or by 1.9 and 2.1 log CFU/g, respectively, when stored at 10 °C. The chitosan-ZnO nanoparticle coating was not significantly different (p > 0.05) but was slightly better than chitosan alone as an active, smart packaging material in food applications.


Asunto(s)
Antiinfecciosos/farmacología , Queso/microbiología , Quitosano/química , Escherichia coli O157/efectos de los fármacos , Óxido de Zinc/química , Antiinfecciosos/química , Quitosano/farmacología , Recuento de Colonia Microbiana , Escherichia coli O157/crecimiento & desarrollo , Microbiología de Alimentos , Almacenamiento de Alimentos , Nanopartículas/química , Sales (Química)/análisis , Temperatura , Óxido de Zinc/farmacología
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