• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.8 no.2
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• pp.49-59
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• 2002

The main function of plastic materials in food packaging is to preserve a food for safe transportation and storage. The interactions between food and plastic materials in food packaging have become increasingly important for food quality and safety because monomer, low molecular weight components, or additives of plastic packaging materials can migrate into a food. The use of antioxidants in plastic materials can help protect the degradation of film itself and retard the oxidation of a packaged food containing lipid, through the migration of antioxidant from the packaging to a product via an evaporation / sorption mechanism. Nowadays, antioxidant (BHT) impregnated plastic materials are used for commercial food packaging application with the intention of achieving an extended shelf life of food in USA. Alpha tocopherol, as one of the most important free radical scavengers, has been well known in biological systems. Moreover, the potential use of alpha tocopherol as an additive for polymers used in the packaging industry may offer the most positive perception from both consumers and manufacturers. Alpha tocopherol has been used as an antioxidant for polyolefin resins fabricated to both bottles and film and has applications in the food packaging industry as a replacement for BHT. Today, alpha tocopherol offers an attractive choice for use as an antioxidant in polymers. This paper provides an overview of antioxidant effectiveness and applications for its use by the food packaging industry based on the evaporation-sorption mechanism of a packaging model product, where quality is associated with lipid oxidation. Important analytical techniques for predicting antioxidant interaction between the package system and product are discussed.

• Korean Journal of Food Science and Technology
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• v.4 no.4
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• pp.245-251
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• 1972

In the present study, the relative effectiveness of BHA, ascorbic acid, and BHA+ascorbic acid on the rancidity development of potato chips in various conditions were examined. BHA, ascorbic acid, and their mixture (BHA 0.05%, As. A 0.1%, and BHA 0.05%+As. A 0.1% relative to the weight of the potato chips) were dissolved respectively in 95% ethyl alcohol and incorporated to potato chips in the form of atomized mist. When the potato chips were stored in a dark place at $33.0{\pm}0.5^{\circ}C$, BHA was very effective in retarding the rancidity development of the potato chips. Ascorbic acid showed some antioxidant activity, but it was less effective than BHA. When BHA and ascorbic acid were used together, the antioxidant activity of the mixture appeared to be primarily due to BHA. Irradiation of direct sunlight to the potato chips, which were covered with coloress transparent polypropylene films, reduced the antioxidant activity of BHA incorporated to them. Ascorbic acid appeared to lose its antioxidant activity completely under the same condition. BHA retained a considerable degree of antioxidant activity when yellow transparent polypropylene films were used to cover the potato chips. Ascorbic acid, however, kept little antioxidant activity even in this condition.

• Korean Journal of Organic Agriculture
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• v.25 no.1
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• pp.187-201
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• 2017

This study was conducted to elucidate the effect of mulching materials on growth characteristics, saponin contents and antioxidant activity of Platycodin grandiflorum Ridix roots for organic farming. Plastic film, sawdust and rice bran were treated by mulching with several different methods after transplanting P. grandiflorum Radix. In root length, when plastic film plot, sawdust plot and rice bran plot were treated, root length was recorded the highest scores (24.0~27.5 cm) in plastic film plot and sawdust plot. Root width was recorded the highest score (30.0 mm) in plastic film plot. Also, the number of fine-roots was the highest in plastic film plot (36.0). Fresh weight, which affects directly yield, was the highest in plastic film plot (130 g/plant). The contents of platycodin D3 and deapioplatycodin D were shown to 111.2 and 48.1 mg/100 g, the highest values were observed in sawdust plot. The total polyphenol and flavonoid contents were recorded the highest scores (11.0 and 8.6 mg/g, respectively) in plastic film plot. In this study we confirmed that there were differences among mulching materials in growth characteristics, saponin contents and antioxident activity of P. grandiflorum roots.

• Microbiology and Biotechnology Letters
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• v.50 no.3
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• pp.375-386
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• 2022

In the present study, four distinctly colored bacterial isolates that show intense pigmentation upon brief ultraviolet (UV) light exposure are chosen. The strains are identified as Micrococcus luteus (Milky yellow), Cryseobacterium pallidum (Yellow), Cryseobacterium spp. (Golden yellow), and Kocuria turfanensis (Pink) based on their morphological and 16S rDNA analysis. Moderate salinity (1.25%), 25-37℃ temperature, and pH of 7.2 are found to be the most favorable conditions of growth and pigment production for all the selected isolates. The pigments are extracted using methanol: chloroform (1:1) and the purity of the pigments are confirmed by high-performance liquid chromatography (HPLC) and thin-layer chromatography (TLC). Further, Fourier transform infrared (FTIR) and UV-Visible spectroscopy indicate their resemblance with carotenoids and flexirubin family. The antioxidant activities of the pigments are estimated, and, all the pigments have shown significant antioxidant efficacy in 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), 2,2-diphenyl-1-picryl-hydrazyl (DPPH), and ferric reducing antioxidant power (FRAP) assays. The UV protective property of the pigments is determined by cling-film assay, wherein, at least 25% of UV sensitive Escherichia coli survive with bio-pigments even after 90 seconds of UV exposure compared to control. The pigments also hold a good sun protective factor (SPF) value (1.5-4.9) which is calculated with the Mansur equation. Based on these results, it can be predicted that these bacterial pigments can be further developed into a promising antioxidant and UV-protectant for several biomedical applications.

• The Korean Journal of Food And Nutrition
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• v.18 no.1
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• pp.19-27
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• 2005

Antioxidative polyethylene films for food packaging were experimentally prepared by fortification of TBHQ(tertiary butylhydroquinone) and dl-a-tocopherol at the weight ratio of 0.05, 0.2 and 0.5%, respectively and laminated with nylon. TBHQ and tocopherol contents in the PE/nylon film were analyzed and the antioxidative effects of film were investigated on the lipid oxidation of semi-dried squid during storage at 5℃ and l5℃. TBHQ contents of TAP 1(TBHQ 0.05%), TAP 2(TBHQ 0.2%) and TAP 3(0.5%) were 38, 146 and 365 mg/100g, respectively. Tocopherol contents of DAP l(tocopherol 0.05%), DAP 2(tocopherol 0.2%) and DAP 3(tocopherol 0.5%) were 33, 139 and 356 mg/l00g, respectively. TBA value and POV during storage of semi-drid squid were affected both by storage temperatures and packaging films. Lipid oxidation during storage was retarded by anti-oxidative films, as TBA value of TAP 3 and DAP 3 revealed about 50% of control after storage at 5℃ for 20 days and similer effects in POV were also observed.

• Food Science of Animal Resources
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• v.25 no.1
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• pp.60-65
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• 2005

Antioxidant films are one active packaging technology that can extend food shelf-life through preventing lipid oxidation, stabilizing color, maintaining sensory properties and delaying microbial growth in foods. Because raw, fresh and minimal processed foods are more perishable during storage or under display conditions than further processed foods, they rapidly lose their original quality. Foods are susceptible to physical, chemical, and biochemical hazards to which packaging films can be effective barriers. Although films incorporated natural (tocopherols, flavonoids and phenolic acids) or synthetic antioxidants (BHT, BHA, TBHQ, propyl gallate) have been extensively tested to improve quality and safety of various foods, food applications require addressing issues such as physical properties, chemical action, cost, and legal approval. Increased interest in natural antioxidants as substitutes for synthetic antioxidants has triggered research on use of the new natural antioxidants in films and coatings. Use of new components (phytochemicals) as film additives can improve food quality and human health. The biosynthesis of plant phenolics can potentially be optimized by active coatings on harvested fruits and vegetables. These coatings can trigger the plants natural proline-linked pentose phosphate pathway to increase the phenolic contents and maintain overall plant tissue quality. This alternate metabolic pathway has been proposed by Dr. K. Shetty and is supported by numerous studies. A new generation of active food films will not only preserve the food, but increase food's nutritional quality by optimizing raw food biochemical production of phytochemicals.

• Journal of Sensor Science and Technology
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• v.28 no.6
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• pp.366-370
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• 2019

In this study, we have successfully fabricated a highly conductive transparent electrode using Ag nanowires, based on piezoelectric polyvinylidene difluoride (PVDF) film, that can be applied as transparent and flexible speakers. The structural morphology of the Ag nanowires was confirmed by a detailed scanning electron microscopy. Ultraviolet-visible spectroscopy demonstrated that the transparent electrode fabricated by the Ag nanowires exhibited a transmittance of above 70%. The transparent electrode also showed very low sheet resistance with high flexibility. We have further developed an anti-oxidation coating layer by using a tetraethyl orthosilicate-poly trimethyloxyphenylsilane (TEOS-PTMS) slurry technique. It was confirmed that the transmittance and sheet resistance of the antioxidant film depends critically on the humidity of the film surface. We believe such Ag nanowire electrodes are a very promising next-generation transparent electrode technology that can be used in future flexible and transparent devices.

• Korean Journal of Food Science and Technology
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• v.43 no.3
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• pp.321-328
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• 2011

Edible films were developed from jujube (Zizyphus jujube Miller) using depolymerization processes of ultrasound and high-pressure homogenization. A 4.6% (w/w) jujube hydrocolloid was treated by ultrasound (600W, 20 min) or homogenized at high pressure (172 MPa, 6 s) and mixed with whey protein isolate, glycerol, xanthan, and sucrose esters of fatty acids to form film-forming solutions from which films were formed by drying. The film prepared by highpressure homogenization (HPH film) produced more homogeneous films without particles than those prepared without depolymerization or with the ultrasound treatment. HPH films possessed the highest tensile strength (4.7MPa), the lowest water vapor permeability ($2.9g{\cdot}mm/kPa{\cdot}h{\cdot}m^2$), and the most uniform and dense microstructures among the films. Flavor profiles of jujube powder and the films were distinguishable. Heat seal strength and oxygen permeability of the HPH films were 44.4 N/m and $0.025mL{\cdot}{\mu}m/m^2$/day/Pa, respectively. Antioxidant activities of jujube power and HPH films were not significantly different.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.23 no.9
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• pp.681-684
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• 2010

The $TiO_2$/ZnS/Ag/ZnS/$TiO_2$ multilayered structure for the transparent electrodes in plasma display panel was designed by essential macleod program (EMP) and the multilayered film was deposited on a glass substrate by direct-current (DC)/radio-frequency (RF) magnetron sputtering system. During film deposition process, the Ag layer in $TiO_2$/Ag/$TiO_2$ structure became oxidized and the filter characteristic was degraded easily. In this study, ZnS layer was adopted as a diffusion blocking layer between $TiO_2$ and Ag to prevent the oxidation of Ag layer efficiently in $TiO_2$/ZnS/Ag/ZnS/$TiO_2$ structure. Based on the AES depth profiling analysis, the Ag layer was effectively protected by the ZnS layer as compared with the $TiO_2$/Ag/$TiO_2$ multilayered films without ZnS as an antioxidant layer. The 3 times stacked $TiO_2$/ZnS/Ag/ZnS/$TiO_2$ films have low sheet resistance of $1.22{\Omega}/{\square}$ and luminous transmittance was as high as 62% in the visible ranges.

• The Korea Journal of Herbology
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• v.21 no.2
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• pp.47-53
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• 2006

Objectives : This study was conducted to determine if Scutellaria baicalensis can be used in cosmetic emulsion cream for patients with atopic dermatitis. Methods : Scutellaria baicalensis extract was obtained with the use of butylene glycol through the pressurized solvent extraction(PSE). The antioxidative activity was assessed through SOD-like activity measurement and skin irritating potential was tested using human patch test. Antimicrobial activity was measured by the clear zone formed against Staphylococcus aureus and Escherichia coli and the rheological effects on the emulsion creams were examined using oscillation test. Results : The SOD-like activity increased dose-dependently and was about 90% at 1,000ppm of Scutellaria baicalesis extract. And Scutellaria baicalensis extract did not show any potential to be irritating to the human skin, but it could not be used as an antimicrobial agent for its poor antimicrobial activity against Staphylococcus aureus. The complex modulus decreased by 1,000 pascals and the loss angle also decreased by 20% with the addition of Scutellaria baicalensis extract into the cosmetic emulsion creams, that is, the extract can confer more elastic property on the vehicle. Conclusion : From those results, Scutellaria baicalensis extract can be effectively used as an antioxidant and reinforces the elastic skincare film formed by the application of cream for patients with atopic dermatitis.