OBJECTIVES This study evaluated the antibacterial effect and mechanical properties of composite resins (LCR, MCR, HCR) incorporating chitosan with three different molecular weights (L, Low; M, Medium; H, High). MATERIALS AND METHODS Streptococcus (S). mutans 100 mL and each chitosan powder were inoculated in sterilized 10 mL Brain-Heart Infusion (BHI) solution, and was centrifuged for 12 hr. ...

In this paper, the newly developed ion exchange phase separation method to create chitosan sub-micron particles is introduced: 1) chitosan was dissolved in a lactic acid aqueous solution; 2) the obtained chitosan solution was added stepwise in a sodium sulfate aqueous solution and cooled down to 5 ̊C to become slightly turbid through agglutination; 3) desalinating and deacidifying of the mixture...

The adsorption of Pb (II) ions onto chitosan beads and cross-linked chitosan beads has been investigated. The epichlorohydrin (ECH) was used as a cross-linking agent. Experiments were carried out as a function of pH, stirring time, adsorbent dosage and concentration of Pb (II) ions. The experimental data of the adsorption equilibrium from Pb (II) solution correlated well with the Langmuir isoth...

Macroporous chitosan spheres encapsulating superparamagnetic iron oxide nanoparticles were synthesized by a facile and effective one-step fabrication process. Ferro-gels containing ferrous cations, ferric cations and chitosan were dropped into a sodium hydroxide solution through a syringe pump. In addition, a sodium hydroxide solution was employed for both gelation (chitosan) and co-precipitati...

The antibacterial activity of water-soluble chitosan derivatives prepared by Maillard reactions against Staphylococcus aureus, Listeria monocytogenes, Bacillus cereus, Escherichia coli, Shigella dysenteriae, and Salmonella typhimurium was examined. Relatively high antibacterial activity against various microorganisms was noted for the chitosan-glucosamine derivative as compared to the acid-solu...

This study presents the first ever data of extracting chitin from the Chiton shell, which was then converted to the soluble chitosan by soaking in the 45% NaOH solution. The obtained chitin and chitosan were characterized by the seven different methods. Antioxidant activity of the extracted chitosan was also evaluated using the two methods. The shell content was divided into calcium carbonate (...

The temperature-dependent hydrolysis and solubility of chitosan in sulfuric acid solutions offer the possibility for chitosan extraction from zygomycetes mycelia and separation from other cellular ingredients with high purity and high recovery. In this study, Rhizomucor pusillus biomass was initially extracted with 0.5 M NaOH at 120 °C for 20 min, leaving an alkali insoluble material (AIM) rich...

This research uses modified orifice method to prepare the O/W type Chitosan encapsulated volatile Citronella Oil microcapsules. In this article, we investigated the forming condition of microcapsules and the influence to sustained release effect of volatile Citronella Oil by applying thermal pretreatment to microcapsules. The results suggest that the forming of microcapsules should be processed...

The effects of steam sterilization and gamma-irradiation on chitosan and thermogelling chitosan-beta-glycerophosphate (GP) solutions containing polyol additives were investigated. The selected polyols were triethylene glycol, glycerol, sorbitol, glucose and poly(ethylene glycol) (PEG). They were incorporated to chitosan solutions prior to sterilization in a proportion ranging from 1 to 5% (w/v)...