• Korean Journal of Fisheries and Aquatic Sciences
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• v.33 no.5
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• pp.418-422
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• 2000

The tensile properties and color of fish meal film under various processing conditions were measured to obtain basic data for biodegradable Alaska Pollack meal protein isolate (APMPI) film. The tensile strength and the elongation of APMPI film were increased with casting volume of APMPI solution but those of APMPI film were weakened with the addition of glycerol amount as well as reduction of pH values. In case of adding various plasticizer, the tensile strength of film was increased in order as follows: sorbitol, polyethylene glycol and glycerol. The elongation was increased in order of polyethylene glycol, sorbitol and glycerol. The tensile strength of film increased with increment of APMPI concentration, but the elongation of film was not affected by APMPI concentration. The tensile strength of APMPI film was decreased with the increment of relative humidity but its elongation was increased with the increment of relative humidity, Not only lightness and yellowness of film added with sorbitol but also redness and total different color of film added with polyethylene glycol showed the highest value in Hunter color system.

• Korean Journal of Food Science and Technology
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• v.44 no.6
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• pp.711-715
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• 2012

A laminate-composite film was developed using industry co-products of defatted mustard meal (DMM) and whey protein isolate (WPI). An individually prepared DMM-based film (DMM film) and a WPI-based film (WPI film) were thermally laminated at $130^{\circ}C$ at a rate of 30 cm/min. Microscopic images exhibited that the DMM film and the WPI film were continuously attached in the laminate without void spaces. The tensile strength, elongation at break, and water vapor permeability for the laminate were 0.7MPa, 4.0%, and $6.9g{\cdot}mm/kPa/h/m^2$, respectively. Stretchability and heat seal strength of the laminate were higher than those of the un-laminated DMM film. The film layers of the laminate were physically overlapped, not forming new biopolymer units induced by molecular interactions. The opportunity for DMM films to be used as food packaging materials for wrapping and sealing could be increased by thermal lamination with WPI films, which improves the stretchability and heat sealability of DMM films.

• Journal of Microbiology and Biotechnology
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• v.11 no.6
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• pp.979-985
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• 2001

A fluorometric detection technique for HDL (High Density Lipoprotein) and LDL (Low Density Lipoprotein) was developed for application in a fiber-optic immunosensor using a protein A Langmuir-Blodgget (LB) film. For the fluorescence immunoassay, antibodies specific to HDL or LDL were imobilied on the protein A LB film, and a fluorescence amplification method was developed to overcome their weak fluorescence. The deposition of protein A using the LB technique was monitored using a surface pressure-are $({\pi}-A)$ curve, and the antibody immobilization of the protein A LB film was experimentally verified. The immobilized antibody was used to separate only HDL and LDL from a sample, then the fluorescence of he separated HDL or LDL was amplified. The amount of LDL or HDL was measured using the developed fiber optic fluorescence detection system. The optical properties resulting from the reaction of HDL or LDL with o-phtaldialdehyde, detection range, response time, and stability of the immunoassay were all investigated. The respective detection ranges for HDL and LDL were sufficient to diagnose the risk of coronary heart disease. The amplification step increased the sensitivity, while selective separation using the immobilized antibody led to linearity in the sensor signal. The regeneration of the antibody-immobilized substrate could produce a stable and reproducible immunosensor.

• Journal of Sensor Science and Technology
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• v.9 no.3
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• pp.208-212
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• 2000

A protein based vision biomembrane was fabricated by adsorbing bacteriorhodopsin into electrochemically polymerized polypyrrole film substrate mainly through strong electrostatic interaction. The immobilized bacteriorhodopsin on the polypyrrole film was demonstrated by SEM and SRET. The light signal transducing function from the bacteriorhodopsin which was adsorbed into Polypyrrole film was evaluated by electroretinogram(ERG). A wave form analysis of the electroretinogram indicated that the adsorbed bacteriorhodopsin retained its activity and light signal was obtained from the protein for at least one month.

• Journal of Microbiology and Biotechnology
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• v.14 no.6
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• pp.1303-1309
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• 2004

In order to extend shelf-life of the packaged or coated foods, an antibacterial edible film was developed. Antimicrobial activities of 9 bacteriocin-like substance (BLS)­producing strains were evaluated after growing them on defatted soybean meal medium (DSMM). Bacillus subtilis was selected among those, because it showed the biggest inhibition zone against 6 problem bacteria in food. The antimicrobial edible film, containing $0.32\%$ of BLS, was produced from the fermented soybean meal with B. subtilis at the optimum condition of pH 7.0-7.5 and $33^{\circ}C$ for 33 h. The antimicrobial activity of the film was over $50\%$ of the maximum activity after film production with heat treatment at $90^{\circ}C$ and pH adjustment to 9. When the soy protein film with BLS was applied on the agar media containing E. coli, the growth inhibition was much higher than the ordinary soy protein film. These results indicate that the soy protein film with BLS from B. subtilis can be used as a new packaging material to extend the shelf-life of foods.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.9
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• pp.1274-1280
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• 2012

Defatted grape seed meal protein (DGP) was extracted, and DGP films containing various plasticizers were prepared. To improve the mechanical properties of DGP film, nanoclay or gelatin was incorporated in the film-forming solution to manufacture DGP composite films. Among the plasticizers of fructose (FRU), sucrose (SUC), and polypropylene glycol (PPG), DGP film containing a SUC : PPG ratio of 2.5:0.5 exhibited the best film-forming ability. Addition of Cloisite $Na^+$ improved the mechanical properties of DGP film. Tensile strength (TS) and elongation at break (E) of the film containing 5% Cloisite $Na^+$ were 1.45 MPa and 71.97%, respectively. Regarding the DGP/gelatin composite films, TS and water vapor permeability (WVP) increased with increasing gelatin amount, whereas E decreased. In particular, the DGP/gelatin (2:2) composite film exhibited 20.95 MPa TS and 12.25% E. These results suggest that the DGP film prepared from defatted grape seed meal can be used as a food packaging material.

• Journal of the Korean Society of Food Science and Nutrition
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• v.30 no.3
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• pp.494-499
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• 2001

To determine optimal conditions for preparing protein isolate film from fish meal, the water vapor permeability (WVP), tensile properties and solubility of fish meal proteinisolate (FMPI) film were measured. FMPI was extracted from fish meal under conditions of various extraction times at $60^{\circ}C$. Extracting time little affected to WVP of FMPI film. The film added with glycerol as plasticizer showed higher WVP than sorbitol added. As extraction time increased up to 1 hr, tensile strength and elongation were increased. While in more extracting time than 1 hr, increasing extracting time made tensile strength and elongation showed negative correlations. The correlation of soluble protein amount and tensile strength showed higher value ($r^{2}=0.83$) than that of elongation ($r^{2}=0.62$).

• Biotechnology and Bioprocess Engineering:BBE
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• v.11 no.5
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• pp.455-461
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• 2006

In this study, we have described a method for the fabrication of a protein chip on silicon substrate using hydrophobic thin film and microfluidic channels, for the simultaneous detection of multiple targets in samples. The use of hydrophobic thin film provides for a physical, chemical, and biological barrier for protein patterning. The microfluidic channels create four protein patterned strips on the silicon surfaces with a high signal-to-noise ratio. The feasibility of the protein chips was determined in order to discriminate between each protein interaction in a mixture sample that included biotin, ovalbumin, hepatitis B antigen, and hepatitis C antigen. In the fabrication of the multiplexed assay system, the utilization of the hydrophobic thin film and the microfluidic networks constitutes a more convenient method for the development of biosensors or biochips. This technique may be applicable to the simultaneous evaluation of multiple protein-protein interactions.

• Korean Journal of Food Science and Technology
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• v.37 no.1
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• pp.142-146
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• 2005

Soy protein isolate (SPI) film was laminated with corn zein or wheat gluten to improve functional properties. Both SPI/corn zein-laminated film (Film B) and SPI/wheat gluten-laminated film (Film C) showed increased tensile strength by 150%, compared to control (Film A). Film C showed significant 253% increase in percentage elongation. Water vapor permeability (WVP) of Films B and C decreased slightly compared to Film A. Solubility values of Films B and C were lower than that of Film A. Hunter color values of Films A and C were not significantly different, while Film B showed yellowness due to presence of corn zein. These results suggest SPI/wheat gluten-laminated film is suitable as packaging material.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.6
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• pp.1063-1067
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• 2004

To elucidate the effect of protein films containing an antioxidant on lipid oxidation of fish paste products during storage, zein and soy protein isolate (SPI) films containing green tea extract were prepared and their physical properties were examined. Tensile strength and elongation of the protein films decreased by the addition of green tea extract compared to the control. Due to the addition of green tea extract, SPI film had an increase in yellowness, but zein film had a decreased yellowness. Wrapping of fried fish paste products by the zein and SPI films containing the antioxidant retarded lipid oxidation at 2 day storage by 3.6 mg MDA/kg sample and 3.6 mg MDA/kg sample, respectively, for instant fish paste compared to the control. For processed fish paste, they decreased the degree of lipid oxidation by 1.6 mg MDA/kg sample and 0.6 mg MDA/kg sample, respectively.