• Journal of Food Hygiene and Safety
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• v.35 no.3
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• pp.205-212
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• 2020

Foodborne diseases occur frequently and have various being related to the intake of contaminated foods. Seafood products are susceptible to contamination due to higher water content and microorganisms, which combine to give them a short shelf-life. Various approaches have been applied to overcome this problem. Edible coatings that are also biodegradable and biocompatible have been discussed as one of the applicable solutions. These coatings can actually help to maintain seafood quality by inhibiting the growth of microorganisms and delaying the loss of moisture. This paper presents the effects of various natural bio-polymers, antimicrobial substances and physical sterilization techniques such as gamma irradiation, ultraviolet (UV) sterilization, and light-emitting diode (LED) sterilization on seafood coatings.

• Korean Journal of Materials Research
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• v.26 no.4
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• pp.187-193
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• 2016

Fabrication of iron oxide/carbon nanotube composite structures for detection of ammonia gas at room temperature is reported. The iron oxide/carbon nanotube composite structures are fabricated by in situ co-arc-discharge method using a graphite source with varying numbers of iron wires inserted. The composite structures reveal higher response signals at room temperature than at high temperatures. As the number of iron wires inserted increased, the volume of carbon nanotubes and iron nanoparticles produced increased. The oxidation condition of the composite structures varied the carbon nanotube/iron oxide ratio in the structure and, consequently, the resistance of the structures and, finally, the ammonia gas sensing performance. The highest sensor performance was realized with $500^{\circ}C/2h$ oxidation heat-treatment condition, in which most of the carbon nanotubes were removed from the composite and iron oxide played the main role of ammonia sensing. The response signal level was 62% at room temperature. We also found that UV irradiation enhances the sensing response with reduced recovery time.

• Journal of Aquaculture
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• v.15 no.1
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• pp.23-29
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• 2002

To develop techniques for the production of artificial seedling of Corbicula japonica, protocols for induction of spawning and larval development were developed. During the assumed spawning period of August to mid-September, attempts were first made to induce spawning by gonadal incision and UV-irradiation but all in vain. At the end of August, elevated thermal induction evoked 90 % positive response in animals maintained at $3\textperthousand$ salinity. Immersion in (1/1000~3/1000 N) ammonium hydroxide ($NH_4$OH) also induced spawning in 15~45%) of the treated animals at $3\textperthousand$ salinity. Fertilized eggs measured 86$\mum. At 23.0~24.5$^{\circ}C$, the fertilized egos developed into 4-cell stage embryos within 2 hours, trochophores 15 hours, D-shaped larvae 2 days, umbo 9 days and fully grown veligers, ready to infiltrate into the sediment, within 16 days.

• The Korean Journal of Mycology
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• v.16 no.1
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• pp.16-20
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• 1988

Auxotrophic mutants were obtained by UV-irradiation to mycelium of Ganoderma lucidum. Induction rate of auxotrophs was 5.78%. Interspecific fusion products of protoplasts were obtained by polyethylene glycol induced fusion of protoplasts from auxotrophic mutants of Ganoderma lucidum and Ganoderma applanatum. Fusion products were selected by means of the comparison with the mycelial growth rate and colony morphology. Fusion products were confirmed by mycelial morphology and esterase isozyme pattern. Some segregants were observed and fusion product produced fruit bodies.

• Journal of Environmental Science International
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• v.17 no.11
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• pp.1195-1201
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• 2008

Enhancing with non-metallic elemental nitrogen(N) is one of several methods that have been proposed to modify the electronic properties of bulk titanium dioxide($TiO_2$), in order to make $TiO_2$ effective under visible-light irradiation. Accordingly, current study evaluated the feasibility of applying visible-light-induced $TiO_2$ enhanced with N element to cleanse aromatic compounds, focusing on xylene isomers at indoor air quality(IAQ) levels. The N-enhanced $TiO_2$ was prepared by applying two popular processes, and they were coated by applying two well-known methods. For three o-, m-, and p-xylene, the two coating methods exhibited different photocatalytic oxidation(PCO) efficiencies. Similarly, the two N-doping processes showed different PCO efficiencies. For all three stream flow rates(SFRs), the degradation efficiencies were similar between o-xylene and m,p-xylene. The degradation efficiencies of all target compounds increased as the SFR decreased. The degradation efficiencies determined via a PCO system with N-enhanced visible-light induced $TiO_2$ was somewhat lower than that with ultraviolet(UV)-light induced unmodified $TiO_2$, which was reported by previous studies. Nevertheless, it is noteworthy that PCO efficiencies increased up to 94% for o-xylene and 97% for the m,p-xylene under lower SFR(0.5 L $min^{-1}$). Consequently, it is suggested that with appropriate SFR conditions, the visible-light-assisted photocatalytic systems could also become important tools for improving IAQ.

• Microbiology and Biotechnology Letters
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• v.13 no.1
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• pp.41-49
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• 1985

Bacillus sphaericus was mutagenized with UV light irradiation and dimethyl sulfate. Thirty-five conditional lethal temperature-sensitive(ts) mutants were isolated at the nonpermissive temperature of $42^{\circ}C$ and classified into three groups by their growth characteristics on the nutrient broth, peptone glucose yeast extract agar and mineral salts agar. First was the lethal ts group, 24 mutants, which did not grow at the nonpermissive temperature, the second, 9 mutants, was the less growth is group whose growth was restricted to one-half, and the third, 2 mutants, was the cold lethal ts group whose growth was restricted at the permissive temperature($25^{\circ}C$and $30^{\circ}C$)

• Analytical Science and Technology
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• v.31 no.5
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• pp.179-184
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• 2018

Diphencyprone (DPCP) is frequently used as a compounded preparation in dermatology for the treatment of alopecia and recalcitrant warts based on the immune reaction of skin allergy. However, DPCP is a non-recognized agent in Pharmacopoeia, because there are no criteria or analytical method for quality control of its powder and formulation. DPCP is unstable under light irradiation because as it easily decomposes to diphenylacetylene (DPA). This study aims to develop a simultaneous HPLC analytical method for analyzing DPCP and DPA in the raw materials and compounded preparation. The method required a C18 column ($250{\times}4.6mm$, $5{\mu}m$) at $40^{\circ}C$ with a mobile phase of (A) 0.01 M phosphoric acid in water and (B) acetonitrile at UV 220 nm. DPA conversion to DPCP in the powder and compounded preparations was accelerated after light exposure for 60 min. In addition, this resulted in different patterns depending on the wavelength of light and the formulation. That is, DPCP in compounded preparation was more unstable than that in the powder. However, the DPCP formulation in amber bottles was observed to remain stable, although the measured concentrations of DPCP were somewhat different from the nominal concentration of the compounded preparations. The control of the exact concentration is required for effective disease treatment, depending on the state of the patient. In conclusion, these results will be useful for the recognition of DPCP in Pharmacopoeia and new DPCP formulation development to prevent photodecomposition.

• Nutrition Research and Practice
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• v.10 no.4
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• pp.371-376
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• 2016

BACKGROUND/OBJECTIVES: Chronic ultraviolet (UV) exposure-induced reactive oxygen species (ROS) are commonly involved in the pathogenesis of skin damage by activating the metalloproteinases (MMP) that break down type I collagen. Adenophora remotiflora (AR) is a perennial wild plant that inhabits Korea, China, and Japan. The present study investigated the protective effects of AR against UVB-induced photo-damage in keratinocytes. MATERIALS/METHODS: An in vitro cell-free system was used to examine the scavenging activity of 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical and nitric oxide (NO). The effect of AR on ROS formation, antioxidant enzymes, elastase, MMP-1 level, and mRNA expression of MMP-1 were determined in UVB-irradiated human keratinocyte HaCaT cells. RESULTS: AR demonstrated strong DPPH free radical and NO scavenging activity in a cell-free system exhibiting $IC_{50}$ values of 1.88 mg/mL and 6.77 mg/mL, respectively. AR pretreatment dose-dependently attenuated the production of UVB-induced intracellular ROS, and antioxidant enzymes (catalase and superoxide dismutase) were enhanced in HaCaT cells. Furthermore, pretreatment of AR prevented UVB-induced elastase and collagen degradation by inhibiting the MMP-1 protein level and mRNA expression. Accordingly, AR treatment elevated collagen content in UVB-irradiated HaCaT cells. CONCLUSION: The present study provides the first evidence of AR inhibiting UVB-induced ROS production and induction of MMP-1 as a result of augmentation of antioxidative activity in HaCaT human keratinocytes. These results suggest that AR might act as an effective inhibitor of UVB-modulated signaling pathways and might serve as a photo-protective agent.

• Journal of Korean Society of Environmental Engineers
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• v.31 no.11
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• pp.1019-1024
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• 2009

Visible-light-active $TiO_2-_xN_x$ nanoparticles with a homogeneous anatase crystalline structure were successfully prepared through a hydrolysis of $TiCl_4$ with ammonia solution. The samples were characterized by X-ray diffraction (XRD), Transmission electron microscopy (TEM), $N_2$-sorption, and UV-vis diffuse reflectance spectra (DRS) techniques. The light absorption onset shifted from 390 nm on pure $TiO_2$ to the visible region at 530 nm on nitrogen-doped $TiO_2$. A clear decrease in the band gap was deduced from the DRS results. The photocatalytic activity was evaluated from the photodegradation of congo red solution under visible light irradiation. The photocatalyst showed the highest photocatalytic activity at an optimal value of nitrogen doping concentration. This was suggested that the nitrogen doping should have an important effects on the improvement of photocatalytic activity.

• Journal of Microbiology and Biotechnology
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• v.23 no.10
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• pp.1357-1364
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• 2013

Human skin is continuously exposed to ultraviolet (UV)-induced photoaging. UVA increases the activity of MMP-1 in dermal fibroblasts through mitogen-activated protein kinase (MAPK), p38, signaling. The irradiation of keratinocytes by UVA results in the secretion of the inflammatory cytokine, tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$), and the stimulation of MMP-1 in normal human dermal fibroblasts (NHDFs). Lipoteichoic acid (LTA) is a component of the cell wall of gram-positive Lactobacillus spp. of bacteria. LTA is well known as an anti-inflammation molecule. LTA of the bacterium Lactobacillus plantarum has an anti-photoaging effect, but the potential anti-photoaging effect of the other bacteria has not been examined to date. The current study showed that L. sakei LTA (sLTA) has an immune modulating effect in human monocyte cells. Our object was whether inhibitory effects of sLTA on MMP-1 are caused from reducing the MAPK signal in NHDFs. It inhibits MMP-1 and MAPK signaling induced by UVA in NHDFs. We also confirmed effects of sLTA suppressing TNF-${\alpha}$ inducing MMP-1 in NHDFs.