• Journal of Information Display
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• v.7 no.3
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• pp.13-18
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• 2006

Currently, the flexible organic light emitting devices (OLEDs) are investigated. They are very vulnerable to moisture, and thus have been found to show some problems. Thus, an effective barrier layer is needed to protect from moisture in air. We deposited thin films with magnesium oxide (MgO) and silicon oxide $(SiO_{2})$ compounds mixed at various mixture ratios on flexible polyether sulfone (PES) substrates by an electron-beam evaporator to investigate their applizability for transparent barrier applications. In this study, we found that as the MgO fraction increased, thin films comprised of MgO and $(SiO_{2})$ compounds became more amorphous and their surface morphologies become smoother and denser. In addition, zirconium oxide $(ZrO_{2})$ was added to the above-mentioned compound mixtures. $ZrO_{2}$ made thin mixture films more amorphous and made the surface morphology denser and more uniform. The water vapor transmission rates (WVTRs) of the whole films decreased rapidly. The best WVTR was obtained by depositing thin films of Mg-Si-Zr-O compound among the whole thin films. As the thin mixture films became more amorphous, and the surface morphology become denser and more uniform, the WVTRs decreased. Therefore, the thin mixture films became more suitable for flexible OLED applications as transparent passivation layers against moisture in air.

• Korean Journal of Agricultural Science
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• v.46 no.1
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• pp.151-161
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• 2019

Ashwagandha (Withania sominifera Duanal) is an important medicinal herb with increased demand after discovering its anti-stress and sex stimulating properties that are attributed to the presence of biologically active alkaloid compounds. The aim of this study was to elucidate a proper agro technological package that ensures the optimum growth of Ashwagandha to obtain the finest quality without degrading the pharmacologically active constituents. Mixtures of organic and inorganic fertilizers were combined with direct seeding and transplanted as four different treatments in this study. The fresh and dry weights of the tubers were recorded up to 12 months starting from two months after sowing (MAS) while the shoot height, root length, number of leaves, fresh and dry weights of the shoot and the root with a shoot ratio of up to 6 MAS were determined. The results revealed that the growth of Ashwagandha was not affected significantly by the method of planting, type of fertilizer or their combinations during most of the harvests. However, tubers harvested at 6 MAS had the highest recorded dry tuber weight per plant in all four treatments compared to the early harvests where two direct seeded treatments had the best results. Comparison of the phytochemical compounds showed that direct seeding with organic fertilizer had the highest recorded values for alkaloid and withaferine A contents with a lower percentage of fiber compared to the treatments with inorganic fertilizer. In conclusion, direct seeding with organic fertilizer and tubers harvested at 6 MAS are recommended as the best cultivation conditions and harvesting stage to obtain high quality tubers of Ashwagandha, respectively.

• Journal of Food Hygiene and Safety
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• v.31 no.4
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• pp.227-249
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• 2016

Arsenic and its compounds vary in their toxicity according to the chemical forms. Inorganic arsenic is more toxic and known as carcinogen. The provisional tolerable weekly intake (PTWI) of $15{\mu}g/kg$ b.w./week established by the Joint FAO/WHO Expert Committee on Food Additives (JECFA) has been withdrawn, while the EFSA panel suggested $BMDL_{0.1}$ $0.3{\sim}8{\mu}g/kg\;b.w./day$ for cancers of the lung, skin and bladder, as well as skin lesions. Rice, seaweed and beverages are known as food being rich in inorganic arsenic. As(III) is the major form of inorganic arsenic in rice and anaerobic paddy soils, while most of inorganic arsenic in seaweed is present as As(V). The inorganic arsenic in food was extracted with solvent such as distilled water, methanol, nitric acid and so on in heat-assisted condition or at room temperature. Arsenic speciation analysis was based on ion-exchange chromatography and high-performance liquid chromatography equipped with atomic absorption spectrometry and inductively coupled plasma mass spectrometry. However, there has been no harmonized and standardized method for inorganic arsenic analysis internationally. The inorganic arsenic exposure from food has been estimated to range of $0.13{\sim}0.7{\mu}g/kg$ bw/day for European, American and Australian, and $0.22{\sim}5{\mu}g/kg$ bw/day for Asian. The maximum level (ML) for inorganic arsenic in food has established by EU, China, Australia and New Zealand, but are under review in Korea. Until now, several studies have conducted for reduction of inorganic arsenic in food. Inorganic arsenic levels in rice and seaweed were reduced by more polishing and washing, boiling and washing, respectively. Further research for international harmonization of analytical method, monitoring and risk assessment will be needed to strengthen safety management of inorganic arsenic of foods in Korea.

• Journal of Adhesion and Interface
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• v.18 no.1
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• pp.13-24
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• 2017

In this study, nanoparticles which encapsulated hydrophobic antimicrobial compounds with 50wt% of payload and 70%of solid content were prepared. These nanoparticles could be dispersed at water as well as various medium. Water dispersible organic-inorganic (O-I) hybrid nanoparticles were first prepared using alkoxysilane-functionalized amphiphilic polymer precursors through a conventional sol-gel process. Hydrophobic antimicrobial compound, Eugenol encapsulated nanoparticles were prepared using these O-I hybrid nanoparticles through a new nanoprecipitation process. The effect of various preparation on the size of nanoparticles, amount of payload, antimicrobial activity, and release rate of encapsulated compounds was investigated. All eugenol-encapsulated O-I nanoparticles regardless of preparation condition showed the same minimal inhibitory concentration (MIC) (50mg/ml) and 99% of antimicrobial activity for every strain. Their antimicrobial activity could maintain longer than two weeks. Especially, eugenol-encapsulated O-I nanoparticles prepared using tetraethoxysilane (TEOS) exhibited the highest payload (50wt%) and the lowest release rate which was owing to higher inorganic content in the O-I nanoparticles. And these O-I nanoparticles dispersed in hexanediol (HD) showed the highest antimicrobial activity and solid content (70wt%) because HD acted as a solvent as well as a antimicrobial agent.

• Analytical Science and Technology
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• v.7 no.2
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• pp.193-199
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• 1994

We have synthesized K-CFICs by the modified two-bulb method. These synthesized compound were analysed with X-ray diffractometer and UV/VIS spectrophotometer. According to X-ray diffraction analysis, the intercalation of potassium between the carbon layers of carbon fiber was better then other intercalants. From obtained data for this deintercalation process, we can see that a number of potassiums were presented as a residue between the carbon layers and this residue compounds had a stability for a long term. Therefore, it is appear that these compounds have a capability as new useful material. From UV/VIS spectrometry data, we can suppose that spectrum of K-CFICs synthesized at $250^{\circ}C$ had only a $R_{min}$, and spectra of any other compounds were not appeared charecteristic peaks because potassium ions were little affect the energy levels of original carbon fiber.

• Journal of Physiology & Pathology in Korean Medicine
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• v.18 no.1
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• pp.93-100
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• 2004

This study was carried out for analyzing pathological and epidemiological factors of osteoporosis and doing pilot test using trial compounds of tuna bone and oriental herbs based on the factors. Osteoporosis is originated from osteoblast, osteoclast, organic and inorganic factors etc. Therefore the pathology of osteoporosis is not simple because the cytokine, growth factors and hormones of the components are various a lot. Taking a view of epidemiological factors of type I osteoporosis, ageㆍmenarcheㆍcholesterolㆍBMI etc. have definite relation to them. So we can approach to aging or consumptive disease in oriental medicine, specifically differential diagnosis of blood depletion with deficiency of qi, deficiency of kidney, deficiency of yin, bony weakness etc. And it should be considered together with rules for maintaining good health or habit concomitantly. Therefore IL1ㆍ6 or TNF αㆍβ are generally used as molecular biological index for osteoblast and osteoclast because the most important index is bone mineral density and strength, but the factors like collagen and noncollagen protein must be accounted as biomarkers. Trial compounds generally showed favorable effects on accompanying subjective symptoms of osteoporosis in the pilot test for menopausal woman. But if she didn't have specific symptoms of osteoporosis there wasn't any specific change. And osteocalcin was increased in case of being under standard level, but wasn't changed in case of normal level. Therefore these trial compounds can be used as a funcdonal diet for type I osteoporotic patients or preventive measures.

• KSBB Journal
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• v.23 no.6
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• pp.484-488
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• 2008

Chlorinated phenols are widely used by the chemical industry as intermediate products in synthesis and previously were frequently applied to various industry fields. Peroxidases catalyze the peroxide-dependent oxidation of a range of inorganic and organic compounds. Peroxidase was shown to mineralize a variety of recalcitrant aromatic compounds and to oxidize a number of polycyclic aromatic and phenolic compounds. Among monomeric phenolic and nonphenolic compounds, peroxidase is known to oxidize its compounds. In this study, a colorimetric assay was developed to quantitatively evaluate the peroxidase activity for rapid screening. Color products of different intensity were developed proportionally to the peroxidase activity on agar plate and 96-well plate. This method correlates well with the RP-HPLC result. Using this screening method, 12 colonies of strain was screened which survived at high concentration of 2,4-DCP (1000 ppm) and with peroxidase activity for the $7^{th}$ round screening step on agar plate. These strains were utilized 2,4-DCP as a sole carbon source and produced peroxidase. After the screening test, four of the bacteria have significant better effect of COD removal on dye waste-water. COD removal of these was from 44% to 61%, respectively.

• Asian-Australasian Journal of Animal Sciences
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• v.23 no.5
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• pp.573-579
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• 2010

This study was conducted to determine the effects of different copper (inorganic and organic) and energy (tallow and glycerol) sources on growth performance, nutrient digestibility, gas emission, diarrhea incidence, and fecal copper concentration in growing pigs by using a 2${\times}$2 factorial design. In this trial, 96 pigs (63 d of age) were employed, with an average initial weight of 28.36${\pm}$1.14 kg. The dietary treatments were i) basal diet with 134 ppm copper (Korea recommendation) as $CuSO_4$+tallow; ii) basal diet with 134 ppm Cu as $CuSO_4$+glycerol; iii) basal diet with 134 ppm copper as CuMet+tallow; and iv) basal diet with 134 ppm copper as CuMet+ glycerol. Throughout the entire experimental period, no differences were noted among treatment groups with regard to the magnitude of improvement in ADG (average daily gain), ADFI (average daily feed intake) and G/F (gain:feed) ratios. The nitrogen (N) digestibility of pigs fed on diets containing organic copper was improved as compared with that observed in pigs fed on diets containing inorganic copper (p<0.05). An interaction of copper${\times}$energy was observed in the context of both nitrogen (p<0.05) and energy (p<0.01) digestibility. Ammonia emissions were significantly lower in the organic copper-added treatment groups than in the inorganic copperadded treatment groups (p<0.05). Mercaptan and hydrogen sulfide emissions were reduced via the addition of glycerol (p<0.05). No significant effects of copper or energy source, or their interaction, were observed in reference to diarrhea appearance and incidence throughout the entirety of the experimental period. The copper concentration in the feces was significantly lower in the organic copper source treatment group than was observed in the inorganic copper source treatment group (p<0.05). The results of this experiment show that organic copper substituted for inorganic copper in the diet results in a decreased fecal copper excretion, but exerts no effect on performance. The different energy (tallow and glycerol) sources interact with different copper sources and thus influence nutrient digestibility. Glycerol supplementation may reduce the concentrations of odorous sulfuric compounds with different Cu sources.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.5
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• pp.2527-2533
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• 2016

Sensitising cancer cells and at the same time desensitizing normal cells is a double task in cancer management. Agents which can combat the debilitating side effects of cancer therapeutics and simultaneously synergize with anticancer agents in specifically targeting cancer cells are needed. Selenium, a proven anticarcinogen, gains due importance in terms of its efficacy to combat the side effects of cancer therapy. This study is a comparative analysis of the chemoprotective effects of selenium compounds, methyl selenol (generated from organic selenomethionine (5mmol/L ; METase 40U/L)) and sodium selenite (inorganic form)($30{\mu}M$) in peripheral blood human lymphocytes exposed to cisplatin and mitomycin. Biochemical alterations occurring in many cells during apoptosis include loss of plasma membrane phospholipid asymmetry, DNA fragmentation, and activation of caspase-3. The present study demonstrated that the selenium metabolite and selenite are efficient in protecting lymphocytes undergoing DNA damage and exerted their activity by reducing caspase 3 expression. Interestingly organic methylselenol (MeSe) was found to offer more protective effects compared to inorganic selenite (SeL), by reducing the induction of apoptosis by the cytotoxic agents. This suggests that MeSe and to a lesser extent selenite might have potential for assessment in clinical trials and could be considered as strong candidates in pharmacogenomics or in the nutriprotective arena.

• Microbiology and Biotechnology Letters
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• v.25 no.3
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• pp.311-316
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• 1997

A high xylitol producing yeast was isolated from the sludge of xylose manufacturing factory and then identified as Candida tropicalis DS-72 according to physiological properties. The strain was able to produce xylitol in a high concentration up to 72g/l from 100g/l xylose in 32 hours. Medium optimization for xylitol production by C. tropicalis DS-72 was performed. Effect of various nitrogen sources on xylitol production was investigated. Of nitrogenous compounds, yeast extract was the most suitable organic nitrogen nutrient for the enhancement of xylitol production. However, inorganic nitrogen resulted in a low cell concentration and did not produce xylitol. Effect of inorganic salts such as KH$_{2}$PO$_{4}$, and MgSO$_{4}$, 7H$_{2}$O on xylitol production was also studied. Optimal medium was selected as xylose 100g/l, yeast extract 10g/l, KH$_{2}$PO$_{4}$, 5 g/l and MgSO$_{4}$, 7H$_{2}$O 0.2 g/l. Xylitol of 88 g/l was produced from 100 g/l xylose in 30 hours using the optimal medium in a flask. In a fermentor, a fed-batch culture with 300g/l xylose was carried out. A final xylitol concentration of 240 g/l in the culture could be obtained in 43 hours of culture time by maintaining the high level of dissolved oxygen during growth phase and limiting the dissolved oxygen in the same culture during production phase. This result corresponded to a xylitol yield of 80% and a xylitol productivity of 5.58 g/1-h.