• Food Science and Biotechnology
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• v.15 no.3
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• pp.478-481
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• 2006

This study investigated the antimicrobial activity of soy protein isolate (SPI) film containing green tea extract (GTE, 1-4%, w/w) on dental caries-inducing bacterium (Streptococcus mutans), food pathogenic (Staphylococcus aureus, Escherichia coli 0157, Salmonella typhimurium), and spoilage (Pseudomonas aeruginosa) bacteria. The physical and mechanical properties of the SPI film containing GTE were also studied. The SPI film containing GTE (4%, w/w) exhibited good antimicrobial activity against S. mutans and S. aureus. The antimicrobial activity of the SPI film containing GTE increased against S. mutans as the concentration of GTE increased up to 4%(w/w). SPI films containing GTE showed lower tensile strength and elongation, and higher total soluble matter than those of control SPI film. Therefore, GTE can be used as one of antimicrobial agents for anti-dental caries and food packaging films.

• Proceedings of the Materials Research Society of Korea Conference
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• 2010.05a
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• pp.45.2-45.2
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• 2010

Possessing of carbon nanotubes in biopolymer intrigued much interest due to their mechanical and unique nanoscale surface properties. Surface stiffness can be controlled by the amount of carbon nanotubes in polymer and surface wettability can be altered by the order of nanoscale surface roughness. Protein adsorption mechanism on nanostructured carbon nanotube/polymer thin film will be discussed in this study. In addition, we identified that mechanical stimuli also contribute the messenchymal stem cell and bone cell interactions. Importantly, live cell analysis system also showed altered morphology and cellular functions. Thus, embedding of carbon nanostructures simultaneously contribute to protein adsorption and cellular interactions. In conclusion, this study demonstrated the evidence that nanoscale surface features determine the subsequent biological interactions, such as protein adsorption and cellular interactions.

• Journal of Dairy Science and Biotechnology
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• v.38 no.4
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• pp.189-196
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• 2020

Milk proteins, such as casein and whey protein, exhibit significant potential as natural emulsifiers for the preparation and stabilization of emulsion-based delivery systems. This can be attributed to their unique functional properties, such as the amphiphilic nature, GRAS (generally recognized as safe) status, high nutritional value, and viscoelastic film-forming ability around oil droplets. In addition, milk protein has been used as a coating material in emulsion-based delivery systems to protect bioactive compounds during food processing and storage owing to its unique functional properties. These properties include the ability to bind lipophilic bioactive compounds and antioxidant activity. In this review, we present the use of milk proteins as emulsifiers for the formation of emulsions and food applications of milk protein-stabilized emulsion delivery systems.

• Korean Journal of Materials Research
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• v.16 no.10
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• pp.606-613
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• 2006

This study was purposed to evaluate the influence of anodically oxidized film on titanium (Ti) onto MG-63 osteoblast-like cell attachment and activity. Only scratch lines created by polishing were seen in ASR and ANO-1 groups. About $1.5{\mu}m$-thick homogeneous oxide film which has pores of about $0.5{\mu}m$ diameter were formed in ANO-12. The crystalline structure of the oxide films formed by anodization in phosphoric acid electrolyte was $TiP_2O_7$. The total protein amounts of ANO-1 and ANO-12 groups showed higher values of maximum protein amount than that of AS-R group. At 3 days of incubation, total protein amount showed higher value in ANO-2 when comparing to that of AS-R (p<0.05). Based on the results of ALPase activity test, the degree of MG-63 cell differentiation for initial mineralization matrix formation was similar. For all the test groups after 1 day of incubation, MG-63 cells grew healthily in mono-layer with dendritic extensions. After incubation for 3 days, the specimen surfaces were covered more densely by cells, and numerous micro filaments were extruding to the extracellular matrix.

• Journal of Dairy Science and Biotechnology
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• v.41 no.4
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• pp.219-229
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• 2023

Consumer demand for products with health benefits and natural ingredients is significant for the expansion of functional foods. Edible films and coatings are an excellent way to diversify the market for functional foods and as substitutes for the prevailing packaging and products. Incorporation of whey protein (WP) and its active ingredients into edible films and coatings is a promising technique that can be applied to various food products. Numerous combinations can be used on an industrial scale depending on the purpose, product, nature of the film, type of active ingredient, and type of inclusions. In this review, we describe several characteristics of edible WP films and coatings used as novel packaging materials. WP-based packaging can play a beneficial role in sustainability because of the option of recycling materials rather than incinerating, as in synthetic laminates, because of the use of natural byproducts from the food industry as raw materials. However, cost-effectiveness is a driving force against industrial setbacks in current and future WP processing developments. The industrial application of this new technology depends on further scientific research aimed at identifying the mechanism of film formation to improve the performance of both the process and product. Furthermore, research such as consumer studies and long-term toxicity assessments are required to obtain significant market shares.

• Food Science of Animal Resources
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• v.43 no.6
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• pp.1128-1149
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• 2023

In order to extend the shelf life of refrigerating raw lamb by inhibiting the growth of microorganisms, preventing the oxidation of fat and protein, and absorbing the juice outflow of lamb during storage, an active packaging system based on plastic/gelatin bilayer film with essential oil was developed in this study. Three kinds of petroleum-derived plastic films, oriented polypropylene (OPP), polyethylene terephthalate, and polyethylene, were coated with gelatin to make bilayer films for lamb preservation. The results showed significant improvement in the mechanical properties, oxygen, moisture, and light barriers of the bilayer films compared to the gelatin film. The OPP/gelatin bilayer film was selected for further experiments because of its highest acceptance by panelists. If the amount of juice outflow was less than 350% of the mass of the gelatin layer, it was difficult for the gelatin film to separate from lamb. With the increase in essential oil concentration, the water absorption capacity decreased. The OPP/gelatin bilayer films with 20% mustard or 10% oregano essential oils inhibited the growth of bacteria in lamb and displayed better mechanical properties. Essential oil decreased the brightness and light transmittance of the bilayer films and made the film yellow. In conclusion, our results suggested that the active packaging system based on OPP/gelatin bilayer film was more suitable for raw lamb preservation than single-layer gelatin film or petroleum-derived plastic film, but need further study, including minimizing the amount of essential oil, enhancing the mechanical strength of the gelatin film after water absorption.

• 한국생물공학회:학술대회논문집
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• 2003.04a
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• pp.630-633
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• 2003

Transfer of an electron from one site to another in a molecular or between molecules and/or electrodes is one of the most fundamental and ubiquitous processes in chemistry, biology and physics. In this study fusion proteins composed by green fluorescent protein(GFP) and cytochrome b562 were used in fabricating molecular array as an electron sensitizer and electron acceptor, Protein formation onto the substrate was performed by the self-assembly technique. The fusion protein film were analyzed using scanning probe microscope(SPM), Surface Plasmon Resornance(SPR) and hybrid STM/I-V. The results suggest that the proposed molecular photodiode can be used as a basic unit of the memory device.

• Food Science and Biotechnology
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• v.15 no.4
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• pp.631-634
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• 2006

Soy protein isolate (SPI) films were supplemented with cinnamaldehyde (CA) at concentrations of 0.1-0.5 mL/5 g SPI. The effects of CA on film color, tensile strength (TS), percent elongation at break (E, %) and water vapor permeability (WVP) of SPI films were investigated. Generally, total color difference (${\Delta}E$), WVP, and TS of SPI films increased gradually, while E and TSM decreased significantly (p<0.05) as the amount of cinnamaldehyde in the SPI films increased. Cinnamaldehyde can be used as a potential cross-linking agent for preparing SPI films by improving mechanical strength and water resistant properties.

• 한국가시화정보학회:학술대회논문집
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• 2002.04a
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• pp.1-7
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• 2002

This papers describes the preparation and experimental results of a micro mass detection devices based on cantilever and a diffuser-type micro pump using screen printing thick-film technologies and Si micro-machining. PZT-PCW thick films were prepared by new hybrid method based on the screen printing. By applying these PZT-PCW piezoelectric thick films on actuator, a cantilever for mass detection sensor and a micropump for microfluidic element are successfully fabricated. Resonant frequency and displacement of PZT-PCW thick film actuator in air and in liquid are measured by laser vibrometer system as a function of actuator size. The resonant frequency of PZT-PCW thick film actuator in liquid decreases order of 1/2-1/4 due to damping effect. The sensitivity of cantilever is characterized by Au deposition method which has the mass loading effect such as adsorption of protein. The Sensitivity of PZT-0.12PCW thick film cantilever is proportional to detecting area.

• Journal of The Korean Society of Grassland and Forage Science
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• v.21 no.2
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• pp.75-80
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• 2001

This experiment was carried out to determine the effect of storing method and wrapping frequency on the quality of round baled rice straw silage at experimental field of Grassland and Forage Crops Division, National Livestock Research Institute, RDA, Suwon fro 1999 to 2000. Storing methods consisted of erect and lay type, and wrapping frequencies were composed to 2, 4, 6, 8 and 10 film layers. there were no significant difference in feed value between storing methods, but acidity of lay type was significantly higher than that of erect type. According to the wrapping frequency, crude protein(CP) content of 2 film layers treatment was lowest during 6 month storing periods, and that of 4 film layers treatment was lowest during 10 month storing periods. The two film layers treatment which was stored for 10 month was impossible for ruminant to feed it, because it was rotten severely. Storing for 6 month, 2 film layers treatment represented highest pH value by 8.23 and storing for 10 month, 4 film layers treatment showed highest pH value by 7.17. Most of silage ranked grade 3 in quality grade. According to this experiment, it was recommended that application of round bale silage system to fresh rice straw should wrap above 4 film layers for 6 month, and above 6 film layers for 10 month storing periods.