• Archives of Pharmacal Research
• /
• v.28 no.9
• /
• pp.1079-1085
• /
• 2005

The purpose of this study was to investigate the safety of chitosan oligosaccharide and the effects of chitosan oligosaccharide on mercury induced genotoxicity in mice using the micronuclei and chromosome aberration. The micronuclei test was performed by microscopic examination $(\times1,000,\;stained\;using\;a\;May-Grunwald\;solution)$ after administering 0.01, 0.1, and $1\%(10\;mg/mL)$ chitosan oligosaccharide for 7, 60, and 180 days ad libitum in mice. Total micronuclei of 1,000 polychromatic erythrocytes were recorded for each group. There was no difference between the untreated and experimental groups. The intake periods and concentrations of chitosan oligosaccharide did not affect the occurrence of micronuclei in bone marrow cells (P>0.05). The chromosomal aberration test was performed by microscopic examination $({\times}1,000,\;stained\;using\;a\;4\%\;Giemsa\;solution)$ after administering the same concentration of chitosan oligosaccharide to mice, in $F_1,\;F_2,\;F_3$ generations and parents. The frequency of chromosomal aberrations was defined as [Ydr=(D+R)/total number of counted lymphocytes]. Similar to the micronuclei test, there was no difference between the untreated and treated groups. These results showed that the intake periods and concentrations of chitosan oligosaccharide did not affect chromosomal aberrations in bone marrow cells (P>0.05). To investigate the effect of chitosan oligosaccharide on mercury-induced chromosome aberration, mice in each condition were supplied with $^{203}HgCl_2$ and chitosan oligosaccharide ad libitum. Chitosan oligosaccharide significantly inhibited $^{203}HgCl_2-induced$ chromosome aberration in mice. Based on the results of this study, it may be concluded that the chitosan oligosaccharide is a nontoxic material that could be used as a suppressor of heavy metal-induced genotoxicity.

• Textile Coloration and Finishing
• /
• v.18 no.6 s.91
• /
• pp.16-24
• /
• 2006

The purpose of this study is to improve the defects of chitosan crosslinked viscose rayon by ECH and to describe the change of hand of chitosan crosslinked viscose rayon fabrics. The chitosan crosslinked viscose rayon were manufactured by crosslinking process using ECH as crosslinking agent, 2 wt% aqueous acetic acid as a solvent of chitosan and ECH, and 20 wt% aqueous sodium hydroxide as crosslinking catalyst. Viscose rayon were first immersed in the pad bath of the mixed solution of chitosan and ECH, padded up to 100 wt% wet pick-up on weight of fiber(owf), precured on pin frames at $130^{\circ}C$ for 2 minutes, immersed in NaOH solution and finally wash and dry. Antimicrobial properties of the viscose rayon treated with chitosan were measured by the shake flask C.T.M. 0923 test method with staphylococcus aureus(ATCC 6538) as the microorganism. When the concentration of chitosan was increased chitosan crosslinked viscose rayon's LT, WT, B, 2HB and MIU were increased and G, 2HG, SMD, T and $T_m$ were decreased. On the other hand, WT, EM were decreased and RT was increased at $1{\times}10^{-2}M$ ECH. The optimum condition for crosslinking was that ECH concentration was between $1{\times}10^{-2}M\;and\;5{\times}10^{-2}M$. Antimicrobial effects of rayon fabric treated with chitosan was excellent.

• Textile Coloration and Finishing
• /
• v.22 no.2
• /
• pp.132-139
• /
• 2010

Sericin pulverization process was applied by freezing-thawing of sericin protein concentration solution and physicochemical properties of sericin/chitosan blended films were investigated. In sericin pulverization process by freezing-thawing method, the refrigeration storage at $4^{\circ}C$ maximized gelling between sericin molecules, which increased 10% of recovery ratio from sericin concentration solution that using ultrafiltration procedure. In physicochemical properties of sericin/chitosan blended films, the maximum load of chitosan (6.7kgf) had higher than that of sericin (1.2kgf), and the elongation of sericin and chitosan had 96% and 34%, respectively. Also FT-IR analysis of sericin/chitosan blended films showed that both sericin and chitosan films had amide I peak (N-H bond) in $1,521cm^{-1}$ and amide II peak (C=O bond) in $1,630cm^{-1}$. In addition, it could confirm compatibility between both materials as indicated by the decrease in the amide I peak's absorption value as chitosan content increases.

• KSBB Journal
• /
• v.29 no.3
• /
• pp.183-187
• /
• 2014

Sick-building syndrome occurs when indoor air is polluted with harmful volatile organic compounds such as formaldehyde which are contained in furniture or new building materials. In this study, formaldehyde-shielding chitosangel sheet was developed and its performance was evaluated. Chitosan and agar were dissolved in acetic acid solution. The optimal concentrations of chitosan, acetic acid and agar were 3, 3, and 2.5 %(w/w). Formaldehyde was spreaded on gypsum board and then wall paper was attached on it by using glue. When chitosan-gel sheet was attached on this control board, the amount of formaldehyde released from the board was decreased by 63% than in control board. On the other hand, decrease in formaldehyde releasing was only 32% when liquid solution of chitosan was spreaded on the control board. This result clearly indicates that chitosan-gel sheet removes formaldehyde more effectively than liqud solution of chitosan. Furthermore, this type of sheet is more applicable to new building than spraying type.

• Journal of the Korean Society of Clothing and Textiles
• /
• v.34 no.5
• /
• pp.775-783
• /
• 2010

This study examines the dyeability, light fastness, washing fastness, and the antibacterial activity of chitosan and nano silver composite non-woven fabrics dyed with an extracted solution from Chrysanthemum Indicum Linn. The results show that an increase in the chitosan and nano silver percentage resulted in an increase in the $a^*$ values and $b^*$ values; however, the $L^*$ values decreased in the undyed condition. ${\Delta}E$ values of chitosan and nano silver composite non-woven fabrics were higher than cotton 100% non-woven fabrics in the dyed condition with an extracted solution from Chrysanthemum Indicum Linn, and mordant treatments influenced the chrominance change. In the dyed condition with an extracted solution from Chrysanthemum Indicum Linn, an increase in the percentage of chitosan and nano silver resulted in an increase of the K/S values. The dyeability of chitosan and nano silver composite non-woven fabrics increased by mordant treatments. The light fastness and washing fastness of the mordanted non-woven fabrics were better than the non-mordanted. For the antibacterial activity, the bacterial reduction rate of chitosan and nano silver composite non-woven fabrics was 99.9% to Staphylococcus aureus and Klebsiella pneumoniae.

• Restorative Dentistry and Endodontics
• /
• v.47 no.3
• /
• pp.28.1-28.12
• /
• 2022

Objectives: Metalloproteinase-inhibiting agents, such as chitosan, can prevent collagen degradation in demineralized dental substrates, thereby improving the adhesive interface. This study evaluated the bond strength (BS) and chemical and morphological characterization of the adhesive interface after applying chitosan solution to demineralized dentin. Materials and Methods: The 80 third molars were selected. Forty teeth underwent caries induction using the pH cycling method. The teeth were divided according to the treatment: distilled water (control) and 2.5% chitosan solution. The surfaces were restored using adhesive and composite resins. Half of the specimens in each group were aged, and the other half underwent immediate analyses. The teeth were sectioned and underwent the microtensile bond strength test (µTBS), and chemical and morphological analyses using energy-dispersive spectroscopy and scanning electron microscopy, respectively. Data analysis was performed using 3-way analysis of variance. Results: For µTBS, sound dentin was superior to demineralized dentin (p < 0.001), chitosan-treated specimens had higher bond strength than the untreated ones (p < 0.001), and those that underwent immediate analysis had higher values than the aged specimens (p = 0.019). No significant differences were observed in the chemical or morphological compositions. Conclusions: Chitosan treatment improved bond strength both immediately and after aging, even in demineralized dentin.

• Journal of Environmental Health Sciences
• /
• v.29 no.3
• /
• pp.50-58
• /
• 2003

Removal of heavy metal ions (Cd$^{2+}$, Cr$^{3+}$, Cu$^{2+}$, Pb$^{2+}$) by several chitosans was studied and the molecular weight of chitosan was investigated in order to examine the effect of autoclaving. Chitosan were divided into 3 groups (A type, controlled chitosan; B type, autoclaved for 15 min; C type, autoclaved for 60 min). The heavy metal removal capacity and rate of B type chitosan were higher than those of A type and B type chitosan. The molecular weight of chitosan was decreased by the increase of autoclaving time. Therefore, the heavy metal capacity was not well correlated to the molecular weight. Freundlich and Langmuir isotherm was determined from the experimental results of equilibrium adsorption for individual heavy metal ions on chitosan. Langmuir isotherm was well fitted to this experimental data. The heavy metal removal capacity of B type chitosan was in the order of Pb$^{2+}$ > Cu$^{2+}$ > Cd$^{2+}$> Cr$^{3+}$.3+/.$.3+/.

• Journal of Korean Society of Environmental Engineers
• /
• v.22 no.2
• /
• pp.203-210
• /
• 2000

The preparative methods of a chitosan-deposited activated carbon and its characteristics were studied by using three kinds of chitosan with different degree of deacetylation and average molecular weight. The procedure was consisted of the dissolution of chitosan into acid solution, impregnation of activated carbon, agitation, evaporation, and drying. When the chitosan-dissolved acid and its concentration, amounts of chitosan deposited, and agitation conditions were changed, the specific surface area, deposition state on surface, and stability were investigated, and amounts of Cr(VI) adsorbed was measured. In the preparation process, it was proper to agitate the chitosan-dissolved acetic acid solution at room temperature for 1hr. In the deposition of chitosan with low molecular weight, the specific surface area of activated carbon was greatly decreased even at low chitosan loading, but in the case of high molecular weight it was not nearly changed to 10wt% loading. It was known that chitosan was uniformly and physically deposited on activated carbon. The chitosan-deposited activated carbon was stable into the solution over about pH 6. The removal of Cr(VI) was remarkably enhanced by adding the adsorption function of chitosan to the surface of activated carbon with about 5wt% chitosan. It may be therefore used as an adsorbent for removing the pollutants in air and wastewater.

• Animal cells and systems
• /
• v.1 no.2
• /
• pp.337-340
• /
• 1997

The purpose of this study is to evaluate whether water soluble chitosan, a natural nontoxic chelator, can reduce fetal contamination of radiostrontium in pregnant mice. Various forms of water soluble chitosans (10% or 1% powder, or 1% solution) were given to pregnant mice before or after contamination of 0.005 uCi/B.W(g) Sr-85. Transplacental transfer of Sr-85 to fetus was $6.8{\pm}2.7%$ of injected dose, when Sr-85 was administered at the 20th day of pregnancy. Fetal radioactivity was significantly reduced when mother mice were treated with water soluble chitosan before contamination of Sr-85. Water soluble chitosans of 10% or 1% powder, or 1% solution significantly reduced fetal retention of Sr-85 to $2.3{\pm}0.7%$, $2.7{\pm}0.8%$, and $2.0{\pm}0.9%$, respectively. However, fetal contamination was not reduced, when water soluble chitosans of 10% or 1% powder, or 1% solution were administered after maternal contamination of Sr-85. From these data we can conclude that water soluble chitosan could reduce fetal contamination of radiostrontium in pregnant mice, when given before the pregnant mice were exposed to radiostrontium.

• Applied Chemistry for Engineering
• /
• v.9 no.3
• /
• pp.399-403
• /
• 1998

The gelation characteristics of chitosan of different molecular weight were investigated in terms of concentration and temperature of alkari aqueous solution. The average molecular weights and the degrees of deacetylation of the chitosan used were $2.0{\times}10^5$, $5.2{\times}10^5$, $8.2{\times}10^5$ and 85%, respectively. Sodium hydroxide solution was used as a gelation agent. A simple diffusion model was applied to study the gelation rate. The diffusion coefficients of the gelation agent in the chitosan gel increased with increasing its concentration, temperature of the casting solution, and molecular weight of the chitosan.