• Journal of Microbiology and Biotechnology
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• v.20 no.10
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• pp.1367-1377
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• 2010

Scientific research regarding the use of live bacterial cells for therapeutic purposes has been rapidly growing over the years and has generated considerable interest to scientists and health professionals. Probiotics are defined as essential live microorganisms that, when administered in adequate amounts, confer a health benefit on the host. Owing to their considerable beneficial health effects, these microorganisms are increasingly incorporated into dairy products; however, many reports have demonstrated their poor survival and stability. Their survival in the gastrointestinal tract is also questionable. To overcome these problems, microencapsulation techniques are currently receiving considerable attention. This review describes the importance of live probiotic bacterial microencapsulation using an alginate microparticulate system and presents the potentiality of various coating polymers such as chitosan and polylysine for improving the stability of this microencapsulation.

• Applied Chemistry for Engineering
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• v.33 no.4
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• pp.444-450
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• 2022

The effect of coated polyester (PET) textiles with metal oxide, chitosan, and copper ion on the antibacterial and antiviral activities was evaluated to investigate the applicability of multi-coated PET textiles as antiviral materials. Compared to coated PETs with a single agent, multi-coated PETs reduced the loading amount of coating materials as well as the contact time with bacteria for a bacterial cell number of < 10 CFU/mL, which was not detectable with the naked eyes. Metal oxides generate reactive oxygen species (ROS) such as free radicals by a catalytic reaction, and copper ions can promote contact killing by the generation of ROS. Chitosan not only enhanced antibacterial activities due to amine groups, but enabled it to be a template to load copper ions. We observed that multi-coated PET textiles have both antibacterial activities for E. coli and S. aureus and antiviral efficiency of more than 99.9% for influenza A (H1N1) and SARS-CoV-2. The multi-coated PET textiles could also be prepared via a roll-to-roll coating process, which showed high antiviral efficacy, demonstrating its potential use in air filtration and antiviral products such as masks and personal protective equipment.

• Korean Journal of Food Science and Technology
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• v.31 no.5
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• pp.1308-1314
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• 1999

The effects of modified atmosphere(MA) packaging and coating on the quality of mushroom (Agaricus bisporus) were investigated. Whole mushrooms(100 g) were packed with polyvinyl chloride(PVC) film wrap, PD941 and PD961 film bags and were stored in a chamber at $12^{\circ}C$ and 80% RH for 6 days. Gas composition of packages, respiration rate, weight loss, color and maturity index of MA packaged mushrooms were examined. The wrap packaged mushrooms showed different level of internal $CO_2$ concentrations among water washed, chitosan coated and $CaCl_2$ coated subgroups significantly at 5% level. The maximum $CO_2$ concentration of PD941 and PD961 packages for all coated showed $4.1{\sim}4.7%$ and $10.4{\sim}11.7%$, respectively, for the first day. PD961 package showed the lowest $O_2$ concentration compared to other groups. There were no significant respiration rate differences between wrap packed and PD941 packaged. Respiration rate of water washed. chitosan coated and $CaCl_2$ coated in PD961 packaged was 192 mg, 226 mg and 245 mg, respectively. Maturity index of PD961 packaged were not significantly different among the water washed, chitosan and $CaCl_2$ coated packages. Chitosan coating showed a negative effect on color change of mushrooms. The weight loss of 961 packaged was lower $(7.0{\sim}8.0%)$ that those of wrap packaged and PD941 packaged.

• Proceedings of the KOSOMBE Conference
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• v.1997 no.11
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• pp.337-342
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• 1997

Dental implant has been increasingly used to recover the masticatory unction of tooth. It has been well known that the success of dental implant is heavily dependent on initial stability and long-term osseointegration due to optimal stress distribution in the surrounding bones. The role of periodontal ligament, removed during operation, is to absorb impact force and to distribute them to alveolar bone. or this reason, the study for artificial periodontal ligament has become an important issue in this field. In this study, chitosan was coated on dental implant or the purpose of replacing the role of intact periodontal ligament. The results by experiment and FEM analysis showed : I) Initial stability of dental implant was significantly increased(35%) when the implant was coated with chitosan. II) The coated implant showed higher impact absorption, more even stress distribution and lower stress magnitude under impact force than uncoated implant. Accordingly, the micro-fracture of the surrounding bones due to impact force would be lessened by chitosan coating on dental implant.

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 2007.11a
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• pp.161.1-161.1
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• 2007

• Bulletin of the Korean Chemical Society
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• v.30 no.8
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• pp.1719-1723
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• 2009

The LiFeP$O_4$ powder was synthesized by using the solid state reaction method with Fe($C_2O_4){\cdot}2H_2O,\;(NH_4)_2HPO_4,\;Li_2CO_3$, and chitosan as a carbon precursor material for a cathode of a lithium-ion battery. The chitosan added LiFePO4 powder was calcined at 350 ${^{\circ}C}$ for 5 hours and then 800 ${^{\circ}C}$ for 12 hours for the calcination. Then we calcined again at 800 ${^{\circ}C}$ for 12 hours. We characterized the synthesized compounds via the crystallinity, the valence states of iron ions, and their shapes using TGA, XRD, SEM, TEM, and XPS. We found that the synthesized powders were carbon-coated using TEM images and the iron ion is substituted from 3+ to 2+ through XPS measurements. We observed voltage characteristics and initial charge-discharge characteristics according to the C rate in LiFeP$O_4$ batteries. The obtained initial specific capacity of the chitosan added LiFeP$O_4$ powder is 110 mAh/g, which is much larger than that of LiFeP$O_4$ only powder.

• Journal of Industrial and Engineering Chemistry
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• v.68
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• pp.229-237
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• 2018

Medical silicone tubes are generally used as implants for the treatment of nasolacrimal duct stenosis. However, side effects such as allergic reactions and bacterial infections have been reported following the silicone tube insertion, which cause surgical failure. These drawbacks can be overcome by modifying the silicone tube surface using a functional coating. Here, we report a biocompatible and superhydrophilic surface coating based on a polysaccharide multilayer nanofilm, which can load and release antibacterial and anti-inflammatory agents. The nanofilm is composed of carboxymethylcellulose (CMC) and chitosan (CHI), and fabricated by layer-by-layer (LbL) assembly. The LbL-assembled CMC/CHI multilayer films exhibited superhydrophilic properties, owing to the rough and porous structure obtained by a crosslinking process. The surface coated with the superhydrophilic CMC/CHI multilayer film initially exhibited antibacterial activity by preventing the adhesion of bacteria, followed by further enhanced antibacterial effects upon releasing the loaded antibacterial agent. In addition, inflammatory cytokine assays demonstrated the ability of the coating to deliver anti-inflammatory agents. The versatile nanocoating endows the surface with anti-adhesion and drug-delivery capabilities, with potential applications in the biomedical field. Therefore, we attempted to coat the nanofilm on the surface of an ophthalmic silicone tube to produce a multifunctional tube suitable for patient-specific treatment.

• Food Science of Animal Resources
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• v.33 no.2
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• pp.229-238
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• 2013

Lactic acid bacteria (LAB) are added to different food products for a long time due to health beneficial effects on human host. LAB is applied in dairy products, such as yoghurt, cheese, and various fermented products, and also in non-dairy products, such as sausages. However, reaching the human gut alive as well as in a sufficient cell amount to exert positive health effects is still a big challenge, due to LAB sensitive character and vulnerability against harsh and detrimental conditions in human digestive system. Keeping physiological activity of sensitive LAB strains alive is for the formulation of novel food products with a probiotic health claim of utmost interest, thus microencapsulation has been applied and investigated as a promising technique for a good and reliable protection. Microencapsulation allows reduced cell injury or cell loss by retaining cells within the encapsulating membrane and can be enforced by spray-drying, emulsion, extrusion, and a range of other technologies in combination with an appropriate coating material, such as alginate, chitosan, and mixture of these two polymers. In this review, established and well-studied microencapsulation techniques with their favored coating materials, as well as the recent applications of microencapsulated LAB into dairy products will be discussed.

• Journal of the Korean Society of Food Science and Nutrition
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• v.46 no.7
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• pp.857-867
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• 2017

This study was performed to encapsulate low molecular weight marine collagen and ${\gamma}$-aminobutyric acid (GABA)-producing lactic acid bacteria to inhibit degradation and improve survival rate during exposure to adverse conditions of the gastro-intestinal tract. Calcium-alginate method was used for the manufacture of a double-layered coated capsule. The inner core material was composed of collagen and lactic acid bacteria, and the coating materials were alginate and chitosan. The sizes and shapes of the double-coated capsule were affected mainly by centrifuge speed and pH. Manufactured capsules were observed with a scanning electron microscope and by confocal laser scanning microscopy to confirm the micromorphological changes of capsules and bacterial cells. As a result, double-layered coated capsules were not degraded at pH 1.2, whereas degradation occurred at pH 7.4. In addition, GABA and collagen were maintained in stable state at pH 1.2. Therefore, double-layered coated capsules developed in this study would not be degraded in the stomach and could be stably delivered to the small intestine to benefit intestinal and dermatic health.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2001.10a
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• pp.149-150
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• 2001

A fish feed being used most widely in aquacultural farm is a moist pellet (MP) feed which has been being prepared by mixing of commercial dry feed and nutritional oil to raw fish ky. The two major problems in the use of MP feed is to be readily dispersed in water of an aquacultural farm, and to cause lipid oxidation and bacteria infection during storage. The former induce an environmental pollution of the farm and the latter lower nutritional values and develop fish diseasees. (omitted)