• Preventive Nutrition and Food Science
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• v.8 no.3
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• pp.278-283
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• 2003

Textural properties of tofu manufactured with micronized full-fat soyflour (MFS) were enhanced by the addition of soy protein isolate, whey protein concentrate, chitosan oligosaccharide and mushroom powder. The MFS solution (14.2% solid content) was converted to semi-solid tofu by a two-stage heat treatment with the addition of 4% coagulant mix. The MFS tofu was evaluated by a compression test as well as sensory evaluation. To produce the semi-solid gel (MFS tofu) with reasonably high strength and toughness, the MFS solution with 14.2% solid content and 7.0% protein had to be heat treated at 121$^{\circ}C$ for 3min. The relative toughness of MFS tofu was increased by the addition of SPI, showing a 144% increase. The toughness of MFS tofu prepared with the MFS/SPI mixture was greatly increased by the addition of WPC at the level of 0.7% and the water separation from MFS tofu was greatly reduced. Furthermore, the toughness and strength of MFS/SPI tofu was enhanced by the addition of 0.1% chitosan oligosaccharide and 0.2% mushroom powder. The sensory evaluation of the tofu fortified with SPI, chitosan oligosaccharide and mushroom powder was superior to that of MFS tofu, with a higher score for overall preference.

• Mycobiology
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• v.36 no.4
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• pp.249-254
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• 2008

Minimal growth inhibitory concentrations (MICs) of chitosan acetate (M.W. 60 kDa) on heterotrophic bacteria (strains MK1, S, and R) isolated from the soft-rotten tissues of Neungee mushroom (Sarcodon aspratus) were measured. The slimy substance produced by the MK1 strain was responsible for the diseased mushroom’s appearance. The S and R strains were members of the Burkholderia cepacia complex. These strains showed different levels of susceptibility toward chitosan acetate. The MIC of chitosan acetate against the MK1 and S strains was 0.06%. The MIC against the R strain was greater than 0.10%. Survival fractions of the MK1 and S strains at the MIC were $3\;{\times}\;10^{-4}$ and $1.4\;{\times}\;10^{-3}$ after 24 h, and $2\;{\times}\;10^{-4}$ and $7\;{\times}\;10^{-4}$ after 48 h, respectively. Survival fractions of the R strain after 24 and 48 hr at 0.1% chitosan acetate were $1\;{\times}\;10^{-2}$ and $6.9\;{\times}\;10^{-3}$, respectively. Compared to the MK1 and S strains, the low susceptibility of the R stain towards chitosan acetate could be due to the ability of the R strain to utilize chitosan as a carbon source. Thirty-eight percent of Neungee pieces treated in a 0.06% chitosan acetate solution for $2{\sim}3$ second did not show any bacterial growth at 4 days, whereas bacterial growth around untreated mushroom pieces occurred within 2 days. These data suggest that chitosan acetate is highly effective in controlling growth of indigenous microorganisms on Neungee. The scanning electron micrographs of the MK1 strain treated with chitosan revealed a higher degree of disintegrated and distorted cellular structures.

• Polymer(Korea)
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• v.28 no.3
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• pp.253-262
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• 2004

Poly(vinyl alcohol)(PVA)/chitosan blend films with non-toxicity, biodegradability, and biocom-patibility were prepared by solution casting. Variation of the physicochemical properties of the blend films was investigated through to several analysis methods. Examination of antibacterial properties revealed that bacterio-static ratios of all blend samples containing chitosan more than 10 wt％ were greater than 99.9％. Moisture regain was increased with increasing chitosan content but the degree of swelling was decreased. Up to chitosan content 15 wt％t, the melting and crystallization temperature of blend films was increased with chitosan content. The blends containing chitosan content 10 and 15 wt％ gave melting temperature 229 and 228$^{\circ}C$, respectively. However, the melting temperature was decreased if chitosan content exceeded 20 wt％. The mechanical properties of the blend films were increased with increasing chitosan content in both dry and wet states. The blend film including 15 wt％ chitosan exhibited unusually high tensile strength.

• Applied Chemistry for Engineering
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• v.10 no.1
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• pp.166-172
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• 1999

Fixed-bed adsorption of metal ions on chitosan bead was studied to remove heavy metal ions in waste water. Chitin was extracted from carb shell and chitosan was prepared by deacetylation of the chitin. The chitosan in bead was used as an adsorbent for heavy metal ions. Freundlich and Langmuir isotherm was determined from the experimental results of equilibrium adsorption for individual metal ion ($Cu^{2+}$, $Co^{2+}$, $Ni^{2+}$) on chitosan bead. Adsorption strength of metal ions decreased in the order of $Cu^{2+}$>$Co^{2+}$>$Ni^{2+}$ ion. Breakthrough curves of single and multicomponent adsorption for metal ions were obtained from the experimental results of fixed-bed adsorption. The breakthrough curves were analyzed by simulation with fixed-bed adsorption equation based on LDFA (linear driving force approximation) adopted LAS (ideal adsorbed solution) theory which can predict multi-component adsorption isotherm from individual adsorption isotherm. The behavior of fixed bed adsorption for single and multi-component system could be nicely simulated by the equation.

• Journal of Fashion Business
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• v.11 no.1
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• pp.136-148
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• 2007

African marigold is a common plant easily available in many flower beds. It has been reported as a practical and prospective resource of dyes since the dyes can be extracted from their bodies as well as petals. In this research, cotton and ramie fabrics which are made from natural cellulose were dyed using the extract of the African Marigold which is a variety of marigold. Dyeing tests were carried out under different pH of the dye solution and mordants. Dyeability was evaluated by examining and measuring surface color, K/S value, and the changes in the maximum absorption wavelength. The probability of improving dyeability was investigated by pre-mordanting with pre-treated chitosan. For the dyeing with marigold extract, the color tone did not differ by pre-mordanting and non-mordanting. Reaction with post-mordanting was excellent, which was colored in various yellow series. The best dyeability was achieved in dye solution of pH 6.5-7.0 which is not conditioned. The largest K/S value and color difference were obtained in tin mordanting. The dye uptake was greatly increased in chitosan pre-treated mordanting compared with the post-mordanting without chitosan pre-treatment. Due to its high heat resistance, African Marigold extract is easy for dye extraction and dyeing, and its dyeability is excellent for natural cellulose fibers. Also, colorfastness was proved to be practically usable.

• 한국생물공학회:학술대회논문집
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• 2000.11a
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• pp.65-68
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• 2000

To obtain quality germinated brown rices containing high levels of ${\gamma}-amonobutyric\;acid$(GABA), chitosan was appliec during the germination of brown rices. The GABA contents of germinated brown rices (1,035 umole/g fresh weight) with 100 ppm chitosan solution for 72 hr were higher than those of ungerminated brown rices (136 nmole/g fresh weight) and brown rices germinated with water (771 nmole/g fresh weight) or with lactic acid (728 nmole/g fresh weight). In addition to the enhancement of GABA, germination in the chitosan solution increased alanine and decreased glutamic acid, aspartic acid and serine in the brown rices. The activity of glutamate decarboxylase was also enhanced by the treatment of chitosan. Furthermore, the germination with chitosan reduced fungi contamination markedly compared with water germination or lactic acid germination. These results suggest that quality germinated brown rices containing high levels of GABA can be obtained by chitosan application.

• Journal of the Korean Society of Food Culture
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• v.9 no.1
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• pp.71-77
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• 1994

This study was undertaken to investigate the physicochemical properties of chitosans produced from chitins which were prepared from shrimp shell under the 4 different conditions(HCl concentration : 1 N, 4 N and reaction temperature $0^{\circ}C,\;20^{\circ}C$). The effects of chitosan on the properties of Kakdugi during storage also were examined. Viscosity of chitosan was markedly different$(313.1{\sim}98.8\;cps)$ depending on the production conditon. Chitosan solution showed pseudoplastic property. The infrared(IR) spectrums of chitosans prepared under the conditions of this study were very simillar, and the degree of deacetylation of chitosan was relatively high$(92{\sim}96%)$ independent of the extraction conditions of chitin. As the storage period was extended, markedly lower pH and higher titratable acidity were resulted in all the groups. Throughout the storage period, pH and titratable acidity of kakdugies with chitosan were higher and lower, respectively than those of control. Viscosity of kakdugi juice was significantly different among the groups and as the storage period increased, the juice viscosity decreased. At the eighth day of storage, the juice of control group was more viscous than those of kakdugies containing chitosan. Throughout the storage period the numbers of total microorganisms and of microorgarnisms of Leuconostoc genus in control kakdugi tended to be higher and lower, respectively than those in kakdugies containing chitosan. The growth of Lac. plantarum was slightly lower in kakdugi containing chitosan C produced at low HCl concentration and high temperature compared to the others.

• Journal of Veterinary Clinics
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• v.24 no.2
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• pp.99-103
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• 2007

The antibacterial efficacy of 0.1% (w/v) chitosan solution against Staphylococcus intermedius isolated from a dog with superficial pyoderma was evaluated in vitro and in vivo. The exposure time for the 0.1% chitosan solutions at different pH to be able to eliminate the bacterial cells and the effect of pH of the solutions on antibacterial activity was tested at the same time in vitro. The antibacterial activity of chitosan was compared to other antibacterial agents including 2.5% benzoyl peroxide, 0.5% chlorhexidine acetate, 0.1% chitosan solution combined with 2.5% benzoyl peroxide and chitosan combined with 0.5% chlorhexidine using a modified detergent scrub quantitative technique in 10 adult mongrel dogs in vivo. They were able to eliminate a number of bacteria after the exposure time of 10 minutes at varying degrees according to the pH of the solutions. The antibacterial activity of chitosan was inversely affected by pH with higher activity at lower pH value. The 0.1% chitosan solution was also efficacious against Staphylococcus intermedius in vivo. The combinations of chitosan with benzoyl peroxide and with chlorhexidine were shown to exert higher activity when compared to those of chitosan alone and benzoyl peroxide or chlorhexidine alone. The 0.1% chitosan solution was considered to be efficacious against Staphylococcus intermedius isolated from a dog with superficial pyoderma in both in vivo and in vitro and have a potential for the clinical applications in the treatment or pyoderma in dogs.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.34 no.5
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• pp.473-477
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• 2001

Chitosan has been used as an effective adsorbant for the treatment of wastewater from seafood processing. We investigated the effects of deacetylation degree (DD) and molecular weight (MW) of chitosan on protein adsorption ability and also the optimum conditions of chitosan treatment for protein adsorption in 3 kinds of protein (albumin, hemoglobin and albumin-myoglobin mixture) solutions. The higher deacetylation degree and the lower molecular weight chitosan, the higher adsorption for water soluble proteins was accomplished. The optimum pHs for adsorption of albumin, hemoglobin and albumin-myoglobin mixture (4: 1, w/w) were 4.0, 7.0 and 4.0 respectively and the optimum time was $3\~4$ hrs for all proteins. Sodium chloride in the model system of protein solution was a preventing factor for protein adsorption ability of chitosan (DD=$80\%$, MW=350 kDa).

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.12
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• pp.1589-1595
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• 2007

This study was carried out to examine the effect of chitosan on the quality of cooked rice. Sensory quality of cooked rice added with 0.1% and 0.5% chitosan was investigated. Taste, flavor and overall acceptability of cooked rice with 0.1% chitosan solution was similar to cooked rice without chitosan. Quality characteristics of cooked rice artificially inoculated with Bacillus spore (CRB), such as number of viable cell, pH, hardness, cohesiveness and color were investigated and compared with CRB added with 0.1% chitosan (CRCB) during storage at $20^{\circ}C\;and\;30^{\circ}C$ for 3 days. The viable cell number of 0.1% chitosan contained in cooked rice inoculated with Bacillus (CRCB) was lower about $1{\sim}1.5$ log at $20^{\circ}C,\;0.5{\sim}1$ log at $30^{\circ}C$ than that of cooked rice inoculated with Bacillus (CRB). The pH of CRCB did not change during storage at $20^{\circ}C$ for 2 days, but decreased in CRCB and CRB during storage at $30^{\circ}C$. The difference of hardness was not noticeable between CRB and CRCB during storage. Cohesiveness and lightness (L value) of CRCB were higher than those of CRB during storage.