Mixture Of Chitosan Research Articles

The control of Botrytis fruit rot in strawberry using combined treatments of Chitosan with Zataria multiflora or Cinnamomum zeylanicum essential oil

This study evaluated the efficacy of the combined application of chitosan (CS) and Zataria multiflora (ZEO) or Cinnamomum zeylanicum essential oils (CEO) on the inhibition of Botrytis cinerea, the causal agent of strawberry gray mold on laboratory media and fruits during storage (7 days at 4 °C followed by 3 days at 20 °C). The application of different CS, CEO and ZEO concentrations inhibited the mycelial growth of the assayed fungus. The mixtures of CS and CEO (CC) or ZEO (CZ) inhibited the mycelia growth in potato dextrose agar, as well as the growth of B. cinerea in artificially infected strawberries stored at both room and cold temperature. Moreover, combined treatments showed more significant mycelial inhibition results and reduction of the IC50, MIC and MFC values compared to pure EOs or CS (p < 0.05). In fruit decay assays, combined treatments (CC or CZ) were able to reduce fungal decay in the range of 60–85 % at 9th day of storage. These results demonstrate the potential of the combined application of CS and CEO or ZEO at sub-inhibitory concentrations to control post-harvest pathogenic fungi in fruits, in particular, B. cinerea in strawberries.

Preparation, Characterization and Evaluation of Antifungal Efficacy of Chitosan/Soy Phosphatidylcholine Topical Films Containing Griseofulvin

Background: Griseofulvin is an antifungal drug and is available as oral dosage forms. Development of topical treatment could be advantageous for superficial fungal infections of skin. The film forming property of chitosan has made it interesting for transdermal/ dermal drug delivery, but showed lack of stability. Soy phosphatidylcholine (PC), besides playing penetration enhancer and solubilizer roles, could enhance the stability and mechanical properties of the film. Films prepared from a mixture of chitosan and PC can achieve the benefits of both materials. Objectives: The aim of this study was to prepare and characterize films formed from blends of chitosan and soy PC for topical delivery of griseofulvin. Materials and Methods: Topical films composed of chitosan and soy PC were prepared by means of casting and solvent evaporation technique. The properties of the films were characterized regarding mechanical properties, swelling, ability to transmit vapor, drug release, thermal behavior and antifungal efficacy against Microsporum gypseum and Epidermophyton floccosum . Results: Presence of soy PC improved mechanical properties, lowered swelling ratio and increased stability of the films. Solubilizing activity of phospholipid resulted in higher flux of drug release from formulation containing higher amount of soy PC. Antifungal efficacy of formulations was confirmed against two species of dermatophytes in vitro. Conclusions: This topical composite film had the potential for griseofulvin delivery to superficial fungal infections.

Potential of Epoxidized Natural Rubber (ENR) as Hydrophobicity Contributor in Chitosan-Urea Fertilizer

This study is to investigate the potential of ENR to be incorporated with chitosan for slow release urea fertilizer. In this research, mixture of chitosan and epoxidized natural rubber (ENR) was used as binder to take advantage of their biodegradable and polar characteristics, respectively. The effect of mixing formulation to the properties of fertilizer was studied. Firstly, the chitosan and ENR were diluted in toluene with the presence of bentonite as filler. Then, urea powder was mixed and stirred for 20 minutes before left to dry overnight in an oven at 60°C. Water absorption and water retention analysis were carried out on compressed pellets. The increase of ENR loading was observed to contribute to the increase of hydrophobic properties of the fertilizer. The findings were supported by compositional analysis using Fourier Transform Infrared spectroscopy (FTIR).

Micro-nanoparticle gels obtained from bark for their use alone and with chitosan and Na-CMC in paper coatings

Abstract The effect of coatings on paper sheets has been studied. For this purpose gels were prepared from unextracted and extracted bark. The gels represented dispersions of micro- and nanoparticles. The coatings were also prepared from mixtures of gels with chitosan solutions in 1% acetic acid and aqueous Na-carboxymethylcellulose (Na-CMC) solutions. The properties – Gurley air resistance, water vapour sorption, and mechanical properties of paper sheets – were tested. For obtaining the gels, the bark was destructed by a thermocatalytic method and then dispersed in water in a ball mill. The gels contained mainly nanoparticles with an average size of about 300 nm. Paper sheets produced by the Ligatne Paper Mill (Latvia) were coated on both sides. Gurley air resistance increases with increasing thickness of the coatings and with increasing gel concentration. At a gel concentration of 10% and a coating thickness of 35 μm, air resistance increases by 57% (gel from unextracted bark) and 72% (gel from extracted bark) compared to uncoated paper sheets. The coatings from bark gels in combination with Na-CMC and chitosan solutions increase further the air resistance. The coatings at gel concentrations up to 6% elevate the burst strength and tensile strength in a dry state. The coatings from mixtures of bark gel and chitosan and Na-CMC heighten further the mechanical properties and elevate the water vapour sorption of paper sheets.

Thermal-Responsive Behavior of a Cell Compatible Chitosan/Pectin Hydrogel.

Biopolymer hydrogels are important materials for wound healing and cell culture applications. While current synthetic polymer hydrogels have excellent biocompatibility and are nontoxic, they typically function as a passive matrix that does not supply any additional bioactivity. Chitosan (CS) and pectin (Pec) are natural polymers with active properties that are desirable for wound healing. Unfortunately, the synthesis of CS/Pec materials have previously been limited by harsh acidic synthesis conditions, which further restricted their use in biomedical applications. In this study, a zero-acid hydrogel has been synthesized from a mixture of chitosan and pectin at biologically compatible conditions. For the first time, we demonstrated that salt could be used to suppress long-range electrostatic interactions to generate a thermoreversible biopolymer hydrogel that has temperature-sensitive gelation. Both the hydrogel and the solution phases are highly elastic, with a power law index of close to -1. When dried hydrogels were placed into phosphate buffered saline solution, they rapidly rehydrated and swelled to incorporate 2.7× their weight. As a proof of concept, we removed the salt from our CS/Pec hydrogels, thus, creating thick and easy to cast polyelectrolyte complex hydrogels, which proved to be compatible with human marrow-derived stem cells. We suggest that our development of an acid-free CS/Pec hydrogel system that has excellent exudate uptake, holds potential for wound healing bandages.

Toward bioderived intelligent nanocarriers for controlled pollutant recovery and pH-sensitive binding.

The pH-triggered formation of supramolecular complexes between the cationic biopolysaccharide chitosan and an environmentally friendly anionic surfactant is exploited for the formulation of selective and controlled-recovery systems. A strong advantage of this system is the very small pH range in which the binding/release process takes place. Because of this high pH responsiveness, chitosan-surfactant complexes are employed for the sequestration of various compounds by binding or releasing them from the complexes. In particular, the selective recovery of a model hydrophobic pollutant in the presence of a hydrophilic one is presented. The process is highly selective and effective, with more than 90% of the hydrophobic dye and ca. 10% of the hydrophilic dye recovered. Furthermore, the method can be extended to the selective recovery of metal ions, and in both cases, the original surfactant and chitosan mixture can be recovered, thereby rendering this an efficient and sustainable process. These showcase experiments depict quite different scenarios in which pH-responsive fully biodegradable polysaccharide-surfactant complexes can be employed and may substitute synthetic products in various fields, e.g., wastewater treatment, cosmetics, and agriculture, thereby yielding environmentally improved approaches.

Enhancing the biological activity of chitosan and controlling the degradation by nanoscale interaction with bioglass.

A nonuniform degradation of physical mixture of organic-inorganic biomaterials increases their risk of failure. In this study a chemical bonding between chitosan and bioglass was used as an alternative product to address this issue. To prepare a homogenous composite, chitosan was functionalized with γ-glycidoxypropyl trimethoxysilane and chemically bonded with bioglass during sol-gel method. The gelation time of these hybrids samples was optimized by varying parameters such as composition of chitosan and temperature. It was shown that gelation time was reduced from 7 days for pure bioglass at 25°C to less than six minutes at 70°C for chitosan 40 vol % bioglass hybrid. Furthermore, the enzymatic degradation after 4 weeks was decreased from 80% mass loss for pure chitosan to 32% for chitosan 40 vol % bioglass hybrid. The results of in vitro study demonstrated that the presence of nanoscale interaction enhanced the bioactivity of chitosan. Additionally, hybrid scaffolds were fabricated with pore sizes in the range of 200-400 µm. These scaffolds were prepared by the addition of sodium bicarbonate during sol-gel method as a gas foaming agent and a neutralizer that resulted in decreasing the gelation time of hybrids to less than three minutes. The hybrids fabricated in this study possessed superior characteristics compared to chitosan, also physical mixture of chitosan-bioglass and are promising alternatives for bone tissue engineering applications.

Composite vascular repair grafts via micro-imprinting and electrospinning

Composite vascular grafts formed by micro-imprinting and electrospinning exhibited improved mechanical properties relative to those formed by electrospinning alone. The three-layered composite grafts mimic the three-layered structure of natural blood vessels. The middle layer is made by micro-imprinting poly-p-dioxanone (PPDO), while the inner and outer layers are electrospun mixtures of chitosan and polyvinyl alcohol. The graft morphology is characterized with scanning electron microscopy. For constant graft thicknesses, the PPDO increases the mechanical strength. Cells cultivated on the vascular grafts adhere and proliferate better because of the natural, biological chitosan in the inner and outer layers. Overall, the composite scaffolds could be good candidates for blood vessel repair.

Small-angle X-ray scattering study on pectin–chitosan mixed solutions and thermoreversible gels

Hot solutions containing pectin and chitosan with pectin weight fraction of 0.75, in acidic pH, demonstrate gelation occurring upon cooling to room temperature. This study explores the origin of this gelation using small angle X-ray scattering (SAXS) as the main experimental tool. Modeling SAXS patterns revealed rigid rod conformation in chitosan solutions, whereas pectin formed a self-avoiding chain. In addition, nanometric aggregates were detected in pectin solutions. Pectin and chitosan in mixed solutions adopted a similar semiflexible conformation. The only sample that created a visually stable gel displayed a different pattern, characteristic to polymers gels. Manipulating the composition by adding urea and salts highlighted the important role of hydrogen bonding, which governs the gelation mechanism. Nevertheless, electrostatic interactions were also found to take part in the gelation. To the best of our knowledge, this is the first comprehensive and systematic SAXS study on these pectin–chitosan mixtures.

Astaxanthin encapsulated in beads using ultrasonic atomizer and application in yogurt as evaluated by consumer sensory profile

This study was aimed to produce and examine properties of encapsulated natural astaxanthin in alginate-chitosan beads during 4 weeks' refrigerated storage and to evaluate consumer sensory profile driving consumer acceptability and purchase intent of yogurt containing such beads. The shrimp astaxanthin was encapsulated in matrices comprising the mixture of chitosan and alginate where alginate (1.2 g/100 mL) and chitosan (1.0 g/100 mL) resulted in an encapsulation efficiency of over 90%. Encapsulated astaxanthin maintained the DPPH scavenging activity greater than 50% whereas the iron chelating assay demonstrated the ability below 50%. Consumers (n = 130) evaluated yogurt containing astaxanthin beads for acceptability of appearance, colour, aroma, mouthfeel and overall liking. A binomial (yes/no) scale was employed to evaluate overall acceptance and purchase intent. The results revealed that overall liking score of yogurt with beads was over 6.0 (on the 9-point scale) with the positive acceptance (86.2%) and purchase intent (95.6%). Logistic regression analysis indicated that colour, aroma, taste and overall liking were significant factors affecting overall acceptance and purchase intent of yogurt containing astaxanthin beads.

Synthesis of Chitosan-Coated Magnetic Microparticle Using Glutaraldehyde as Crosslinker and PEG as Spacer Arm and Its Application as Adsorbent of Peat Humic Acid

A simple procedure for synthesis of chitosan-coated magnetic microparticle (CMMP) using glutaraldehyde as a cross-linker and polyethylene glycol (PEG) as a spacer arm has been developed. The functionalized microparticle were prepared using an inexpensive, simple, rapid, one-pot process, based on the heating of chitosan, PEG, and ferrous sulfate mixture at high pH. X-ray diffraction results indicated that the surfacemodified Fe3O4 microparticle did not lead to phase change unlike the pure Fe3O4. Magnetic chitosan adsorbent has been evaluated for removal of peat humic acid from its aqueous solution.

Chitosan improves anti-biofilm efficacy of gentamicin through facilitating antibiotic penetration.

Antibiotic overuse is one of the major drivers in the generation of antibiotic resistant “super bugs” that can potentially cause serious effects on health. In this study, we reported that the polycationic polysaccharide, chitosan could improve the efficacy of a given antibiotic (gentamicin) to combat bacterial biofilms, the universal lifestyle of microbes in the world. Short- or long-term treatment with the mixture of chitosan and gentamicin resulted in the dispersal of Listeria monocytogenes (L. monocytogenes) biofilms. In this combination, chitosan with a moderate molecular mass (~13 kDa) and high N-deacetylation degree (~88% DD) elicited an optimal anti-biofilm and bactericidal activity. Mechanistic insights indicated that chitosan facilitated the entry of gentamicin into the architecture of L. monocytogenes biofilms. Finally, we showed that this combination was also effective in the eradication of biofilms built by two other Listeria species, Listeria welshimeri and Listeria innocua. Thus, our findings pointed out that chitosan supplementation might overcome the resistance of Listeria biofilms to gentamicin, which might be helpful in prevention of gentamicin overuse in case of combating Listeria biofilms when this specific antibiotic was recommended.

Dispersion of FeOOH on Chitosan Matrix for Simultaneous Removal of As(III) and As(V) from Drinking Water

Bio-inorganic chitosan based spherical shaped beads were prepared by dispersing rod-shaped FeOOH nanoparticles into a chitosan matrix for the removal of pure As(III) and As(V) from aqueous media, such as drinking water. A homogeneous mixture of chitosan and ferric nitrate, ferric chloride was prepared respectively with or without oxalic acid. The mixture was added dropwise in to a NaOH bath, where iron salts reacted with NaOH to form FeOOH particles. The scanning electron microscopy (SEM) showed that rod shaped FeOOH particles were distributed homogenously in the chitosan matrix. Diffuse reflective UV-vis (DRUV) spectra revealed that hydrated iron oxide formed a complex with functional groups in chitosan. Adsorption of As(III) and As(V) on different iron salt based bead was found to be pH dependent. The bead prepared from iron nitrate showed better performance for arsenic removal from aqueous solution over the bead that was prepared using iron chloride salt. The bead prepared using chitosan and iron-FeOOH is known as a chitosan-iron oxyhydroxide (CFOH) bead. The CFOH beads were found to be more efficient in removing As(III) from the solution compared to As(V). The adsorption of As(III) and As(V) from aqueous solution on CFOH beads was studied under equilibrium conditions in the concentration range of 1 mg/L to 50 mg/L in the presence of 0.05 M NaNO3 at pH 6.5 and 298 K temperature. The maximum adsorption capacity of the CFOH bead was found to be 5.4 mg/g for As(V) and 7.2 mg/g for As(III) using the Langmuir equation. The presence of sulphate, phosphate, and silicate in aqueous solution had no effects on adsorption of either As(III) or As(V) on CFOH beads but decreased significantly at pH> 8.

The coagulation characteristics of humic acid by using acid-soluble chitosan, water-soluble chitosan, and chitosan coagulant mixtures

Chitosan is a potential substitute for traditional aluminium salts in water treatment systems. This study compared the characteristics of humic acid (HA) removal by using acid-soluble chitosan, water-soluble chitosan, and coagulant mixtures of chitosan with aluminium sulphate (alum) or polyaluminium chloride (PACl). In addition, we evaluated their respective coagulation efficiencies at various coagulant concentrations, pH values, turbidities, and hardness levels. Furthermore, we determined the size and settling velocity of flocs formed by these coagulants to identify the major factors affecting HA coagulation. The coagulation efficiency of acid- and water-soluble chitosan for 15 mg/l of HA was 74.4% and 87.5%, respectively. The optimal coagulation range of water-soluble chitosan (9–20 mg/l) was broader than that of acid-soluble chitosan (4–8 mg/l). Notably, acid-soluble chitosan/PACl and water-soluble chitosan/alum coagulant mixtures exhibited a higher coagulation efficiency for HA than for PACl or alum alone. Furthermore, these coagulant mixtures yielded an acceptable floc settling velocity and savings in both installation and operational expenses. Based on these results, we confidently assert that coagulant mixtures with a 1:1 mass ratio of acid-soluble chitosan/PACl and water-soluble chitosan/alum provide a substantially more cost-effective alternative to using chitosan alone for removing HA from water.

Cinnamon Oil and Chitosan Coating on Orthopaedic Implant Surface for Prevention of Staphylococcus Epidermidis Biofilm Formation.

S. Epidermidis is among the most frequently isolated microorganisms found in -infection related to implanted devices and the formation of biofilm will be more resistant compared to the planktonic form. This study was carried out to determine the effect of coating on stainless steel orthopaedic implants surfaces with cinnamon oil and chitosan as bioadhesive to prevent biofilms formation of S. Epidermidis.The rod shaped stainless steel 316 L orthopaedic implant with 5 mm diameters was coated 2 times using a mixture of cinnamon oil and chitosan 3% and 2% respectively with serial concentration of cinnamon from 0.125% to 2%. The coated implants were then put into tubes that contained bacterial suspension and incubated. Subsequently, the implants were washed with PBS solution followed by MTT soulution and isopropanol acid solution. that related to biofilm formation. The results were expressed in numbers which represents the absorbance level at ELISA readings on 575 nm (A575) wavelength.The stainless steel implant coated with chitosan and cinnamon oil 2% and 1% has lower absorbance level compared with the absorbance level of S.Epidermidis biofilm only. This study showed that mixture of cinnamon oil and chitosan coated on the surface of stainless steel orthopaedic implant has an effect against S.Epidermidis biofilm formation with the minimum cinnamon oil concentration of 1%.

Drug-free chitosan coated poly(isobutylcyanoacrylate) nanoparticles are active against trichomonas vaginalis and non-toxic towards pig vaginal mucosa.

The present work reports a non-conventional therapeutic strategy based on the use of vaginally-applied formulations for the treatment of trichomoniasis due to Trichomonas vaginalis without adding a drug. The formulations were based on a thermosensitive pluronic® F127 hydrogel containing mucoadhesive poly(isobutylcyanoacrylate) nanoparticles coated with a mixture of chitosan and thiolated chitosan (75/25 wt%). The nanoparticles were obtained by anionic emulsion polymerization of isobutylcyanoacrylate. The anti-T. vaginalis activity of the formulations was evaluated in vitro. Chitosan-coated nanoparticles showed a strong anti-T. vaginalis activity at 100 μg/mL independently on the proportion of thiolated chitosan. No anti-T. vaginalis activity was reported neither with chitosan-uncoated poly(isobutylcyanoacrylate) nanoparticles nor with chitosan used as a solution. These results suggest that the anti-T. vaginalis activity was related to poly(isobutylcyanoacrylate) nanoparticles but only when they are coated with chitosan. Histological analysis of ex vivo pig vaginal mucosa in contact with pluronic® F127 hydrogel containing poly(isobutylcyanoacrylate) nanoparticles coated with the mixture chitosan/thiolated chitosan (75/25 wt%) did not reveal any toxicity. This study demonstrated that poly(isobutylcyanoacrylate) nanoparticles coated with chitosan were active against T. vaginalis without adding a drug. Besides their anti-T. vaginalis activity, the formulations are non-toxic towards pig vaginal mucosa.

Oxidative Stability of Spray-Dried Microencapsulated Fish Oils with Different Wall Materials

Multilayer microencapsulation of fish oil was evaluated by using fish gelatin (treated with or without microbial transglutaminase [MTGase]), chitosan, and maltodextrin for its ability to control lipid oxidation. This study showed that a mixture containing gelatin and maltodextrin obtained the highest percentage of core release. The oxidative stability of the formulated mixtures and the bulk oils was investigated during a period of 60 days. The peroxide value (PV) was assessed as a parameter for primary oxidation products, and p-anisidine (p-AV) and thiobarbituric acid reactive sub-stances (TBARS) was used to analyze secondary oxidation compounds. Observation of oxidation products showed that combinations of gelatin and maltodextrin made by adding MTGase and a mixture of gelatin and chitosan were able to increase the oxidative stability, and increases in PV and p-AV and TBARS were found for all oils.

Insights into the mechanisms of chitosan–anionic polymers-based matrix tablets for extended drug release

The aim of this study was to investigate drug release mechanisms from physical mixtures of chitosan–anionic polymers-based matrix tablets and to obtain a comprehensive understanding about release characteristics. Six types of anionic polymers (i.e., Eudragit® L100, sodium alginate, carrageenan, carboxymethylcellulose sodium, carbomer and xanthan gum) and two model drugs (i.e., theophylline and metoprolol succinate) with varied solubility were chosen. Texture analyzer, differential scanning calorimetry (DSC) and Fourier transform infrared spectroscopy (FTIR) were applied to better understand drug release mechanisms. In vitro release experiments were conducted in a pH-changing medium to simulate the physiological condition of the gastrointestinal tract. Interestingly, a common phenomenon was observed in all the CS–anionic polymers-based matrix tablets investigated here, that is, the inner layer of the swollen tablets was coated by CS–anionic polymer polyelectrolyte complexes (PEC)-based film formed by self-assembly. Formation of the in situ self-assembled film was further confirmed by texture analysis, DSC, and FTIR. It was further identified that properties of the film were influenced by the characteristics of anionic polymers and the physiological conditions of the gastrointestinal tract. Moreover, this novel structure could alter swelling and erosion-based release mechanisms of the tablets. In addition, drug release characteristics from CS–anionic polymer systems depended on the properties of anionic polymers and the drug solubility. In conclusion, our studies may broaden current views on cationic polymer–anionic polymer-based oral matrix tablets for extended release.

Modification of collagen and chitosan mixtures by the addition of tannic acid

The properties of collagen/chitosan mixtures with weight ratios: 75/25, 50/50, and 25/75 were modified by the addition of tannic acid. Tannic acid was added in the ratios 2, 5, 10 and 20wt.% based on chitosan. Molecular interactions between the components and structure of the blends were studied by Fourier transform infrared spectroscopy (FTIR). Mechanical properties were measured by a mechanical testing machine. Swelling behavior was measured by immersing the fragments of the blend in phosphate-buffer saline.Infrared spectroscopy showed that cross-linking process by tannic acid occurred in collagen/chitosan mixtures. It was found that compressive modulus decreased with increasing amount of tannic acid in chitosan/collagen blends. Addition of tannic acid improved swelling behavior of those mixtures where collagen was in predominance.The modification of collagen/chitosan mixture using tannic acid can lead to new bespoke materials for potential biomedical applications.

The influence of UV-irradiation on thermal and mechanical properties of chitosan and silk fibroin mixtures

In the present paper the results regarding the influence of UV-irradiation with 254nm wavelength on the thermal and mechanical properties and the intrinsic viscosity of chitosan/silk fibroin mixtures are presented.The mixture of chitosan and silk fibroin in solution and thin films made of chitosan/silk fibroin mixture obtained by solvent evaporation were submitted to the treatment with UV irradiation (wavelength 254nm) for different time intervals. Mechanical properties of thin films made of chitosan/silk fibroin blends before and after UV-irradiation have been investigated by mechanical testing machine and compared with mechanical properties of chitosan films. The changes in such mechanical properties as ultimate breaking strength, percentage of elongation at break and Young Modulus have been investigated.The results have shown, that the mechanical properties of the blends were greatly affected by time of exposure to UV irradiation. Ultimate tensile strength and ultimate percentage of elongation decreased after UV irradiation of the blend. Increasing UV irradiation led to the decrease in Young’s Modulus of the chitosan/silk fibroin blend. Viscosity of chitosan/silk fibroin mixtures decreased after UV-irradiation. Thermal properties of the mixtures have been only slightly altered by UV-irradiation.