• Korean journal of food and cookery science
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• v.12 no.3
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• pp.372-376
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• 1996

Antioxidative activities of the extracts from Schizandra Chinesis Baillon (Omija) with various solvent were compared with some commercial antioxidants. AS (antioxidative index; induction period of oil containing extract/induction period of control oil) of Omija extracts from five kinds of solvents (MeOH, EtOH, BtOH, EA, PE) and other antioxidants were shown as following orders: 0.02% BHT > 0.05% EA > 0.01% MeOH > 0.05% EtOH > 0.1% EA > 0.05% PE > 0.05％ BuOH >> 0.02% alpha-tocopherol. Antioxidative effects of 0.05% EA and 0.05% MeOH extracts during autoxidation (60${\pm}$ 2$^{\circ}C$) were higher than those (If the other extracts but were not greater than that of 0.02% BHT. However, Al of EA and MeOH, EtOH extracts during thermal oxidation (180${\pm}$2$^{\circ}C$) were greater than that of BHT. The antioxidant effect of alpha-tocopherol showed no apparent difference or a prooxidant effect as compared with result of control.

• Food Science of Animal Resources
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• v.31 no.5
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• pp.748-755
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• 2011

This study was carried out to investigate the effect of dietary palm oil supplementation on the quality of the carcass and meat of Hanwoo (Korean cattle). Thirty-month-old steers were fed on a concentration with or without (control) palm oil for 3 mon prior to slaughter. The samples of M. longissimus were taken from all carcasses and then stored at $4^{\circ}C$ for 9 d. The carcass traits, total myoglobin content, pH value, total reducing ability, and myofibrillar fragmentation index were unaffected by supplementation with palm oil. However, the fat content, water-holding capacity, and tenderness were significantly increased by dietary palm oil (p<0.05). In the fatty acid composition, the palm oil group had a higher palmitic acid (C16:0) content and lower polyunsaturated fatty acids (PUFA) content compared to the control group (p<0.05). The lipid oxidation stability, myoglobin oxidation stability, and color stability were increased by dietary palm oil. It is concluded that supplemental palm oil increased the marbling and storage quality but decreased the PUFA in Hanwoo beef.

• Journal of Environmental Impact Assessment
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• v.29 no.3
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• pp.198-209
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• 2020

In this study, electrospun nanofibers made of PAN (polyacrylonitrile) were activated through a physical method to obtain an optimized pore structure. In particular, to enhance the surface alkalinity, the activated carbon fibers (ANFs) were impregnated with tetraethylenepentamine (TEPA) with the aid of HNO₃. Then, the low level (3,000 ppm) CO₂ adsorption capacity for each ANF sample was evaluated. The specific surface area of ANFs increased from 308.4 ㎡/g to 839.4 ㎡/g and the total pore volume increased from 7.882 ㎤/g to 27.50 ㎤/g. Although the TEPA impregnation reduced the specific surface area and pore volume of the ANFs due to blocking of micropores, the HNO₃ pre-oxidation enhanced the amino groups tethered, increasing the amine content from 6.42% to 17.19%, and finally, increased the adsorption capacity of CO₂. This study showed that the sample 60-ANF-HNO₃-TEPA, which was activated for 60 minutes and was impregnated with HNO₃ and TEPA, had the best adsorption capacity for low level (0.3%) CO₂ (in a binary mixture with N₂).

• Journal of Life Science
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• v.20 no.11
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• pp.1595-1602
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• 2010

Oxidation of low density lipoprotein (LDL) has been recognized as an important role in the initiation and progression of atherosclerosis. In this study, effects of allylmercaptan, a major metabolite compound of garlic, was studied on endothelial cell injury induced by oxidized low density lipoprotein (ox-LDL). The antioxidative activity of allylmercaptan was investigated by monitoring a thiobarbituric acid substance (TBARS). Allylmercaptan inhibited LDL oxidation induced by $Cu^{2+}$ at concentrations of 0.1, 1 and 10 mM in a dose dependent manner. Lactate dehydrogenase (LDH) release, as an index of cell injury, and intracellular glutathione levels were determined. Pulmonary artery endothelial cells were preincubated with allylmercaptan at $37^{\circ}C$ and 5% $CO_2$ for 24 hr, washed, and then exposed to 0.1 mg/ml oxidized LDL for 24 hr. Preincubation of endothelial cells with allylmercaptan significantly prevented the LDH release and depletion of GSH. Peroxides were measured directly in 24 well plates using a fluorometric assay. Allylmercaptan inhibited release of peroxides induced by ox-LDL in pulmonary artery endothelial cells. In a free system, allylmercaptan was shown to scavenge hydrogen peroxide. The data indicate that allylmercaptan can protect pulmonary artery endothelial cells from injury caused by oxidized LDL, and suggest that allylmercaptan may be useful for the prevention of atherosclerosis.

• Journal of the Korean institute of surface engineering
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• v.51 no.4
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• pp.207-213
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• 2018

Not only efficiency of chlorine evolution reaction (CER) but also durability namely service life is very important property in dimensional stable anode for Ballast Water Management System (BWMS) for marine ships. Many researchers have been focused on improving efficiency of CER by controlling composition, phase and surface area for a long time, but the efforts to increase durability was relatively small. In this study, we have investigated the effect of $TiO_2$ protective interlayers on efficiency and durability of DSA electrodes. $TiO_2$ protective interlayers were prepared by thermal oxidation at 500, 600 and $700^{\circ}C$ on Ti substrate. And then the DSA electrodes consisting of $Ti/RuO_2-PdO-TiO_2$ were prepared by thermal decomposition method on $TiO_2$ interlayers. The efficiencies of CER of DSA electrodes without $TiO_2$ interlayer and with $TiO_2$ interlayer grown at 500, 600 and $700^{\circ}C$ were 94.19, 94.45, 84.60 and 76.75% respectively. On the otherhand, durabilities were 30, 55, 90 and 65 hours respectively. In terms of industrial aspect, the performance of DSA is considered high efficiency and durability which can correspond to total production of chlorine. If we considered the performance index of DSA as the product of efficiency and durability, performance indices could be recalculated as 28.26, 50.85, 76.14 and 49.89 respectively. As the thermal oxidation temperature increasing, life time were increased remarkerbly, while efficiency of CER was decreased slightly. As a result, DSA electrode with $TiO_2$ interlayer grown at $600^{\circ}C$ has shown about 2.7 times performace of original DSA electrode without $TiO_2$ interlayer.

• Korean Journal of Soil Science and Fertilizer
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• v.32 no.2
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• pp.155-163
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• 1999

Nutrient balance during rice cultivation in the paddy of a local area under the environmental protection for drinking water supply was investigated. To compare nutrient balance in the paddy soil applied with different types of fertilization, 7 treatments were selected as followings : Recommended level of chemical fertilizers(R), Conventional fertilization(CF), Fresh cow manure(FCM), Cow manure compost(CMC), Straw compost+reduced chemical fertilizer(SCF), Fresh straw+recommended level of fertilizers(FSC), and no fertilization as control(C). Here, FCM, CMC and SCF were applied at the same level of total nitrogen as recommended in R. Rice yield was the highest in the recommendation(R) and fresh cow manure (FCM) treatments with $6,730kg\;ha^{-1}$(index 100), and followed by SCF (index 98), FSC (index 98), CMC(index 94), and CF(index 94). But statistically significant difference was not recognized among treatments except the control. Nitrogen infiltration loss was high in the simple chemical fertilizer treatments with $63kg\;ha^{-1}$ in CF and $58kg\;ha^{-1}$ in R during rice cultivation, respectively. Nitrogen infiltration loss was decreased below half level of chemical fertilizer treatments with cow manure treatments ($23kg\;ha^{-1}$ in FCM and $27kg\;ha^{-1}$ in CMC) and with reducing chemical fertilizer treatment by adding straw compost ($25kg\;ha^{-1}$). Phosphate was not leached during rice cultivation in paddy soil of a fluvial deposit type, in which oxidation horizon was developed broadly under around 15 cm depth of surface soil. Phosphate balance (A-B) was closed to 0 in all treatments except cow manure treatment (CMC), in which it was $+30kg\;ha^{-1}$ and show the possibility of over accumulation of phosphate by continuously replicated application of cow manure compost. Potassium balance was negative value in all but straw recycling treatment (FSC). It means that potassium was continuously supplied from soil minerals, uptaken by plants or eluted out of soil. In conclusion, by substituting inorganic fertilizer for organic fertilizer or reducing application rate of chemical fertilizer through mixing organic fertilizer, it would be possible to achieve the same rice yield as in the recommendation treatment and to decrease nutrient leaching below half level in rice paddy soil.

• Journal of Nutrition and Health
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• v.40 no.2
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• pp.138-146
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• 2007

Food irradiation has been steadily increased in many countries concomitantly with increasing international trades. Harmful contaminants naturally occurred from foods which contain high levels of unsaturated fatty acids that are easily oxidized can affect the human anti-oxidation system through the generation of free radicals. Moreover, previous studies proved that ${\gamma}$-irradiation may cause production of free radicals in food. We investigated the effect of ${\gamma}$-irradiated soybeans in relation to oxidative stress in mice. Oxidative index of mice was evaluated by TBARS, DNA fragmentation in various organs such as blood lymphocytes, liver and kidney. Forty male ICR mice were equally divided into 4 groups and fed control diet or ${\gamma}$-irradiated diet containing 50% soybeans (5, 10, and 20 kGy, respectively) for 8 weeks. Peroxide values of the irradiated diets were higher than that of the non-irradiated one and increased according to the storage period. There was no significant difference in weight gain as well as in TBARS value in plasma and kidney of all groups. Liver TBARS value of the group fed with irradiated diet at 20 kGy increased significantly compared with the control group (p < 0.05). DNA oxidative damage as measured by alkaline comet assay showed that % tail DNA in the blood lymphocytes of 5 kGy and 10 kGy groups increased significantly over the control group (p < 0.05). Also, tail moments of 5 kGy and 10 kGy groups were higher than that of the control group. Ultrastructural examination shows myeline figures and swollen mitochondria in parietal and intestinal epithelial cells of the group fed with irradiated diet. Therefore, considering unsaturated fatty acid content, consumption of soybeans ${\gamma}$-irradiated with over 20 kGy or repeatedly may decrease the body's antioxidant mechanism.

• Applied Biological Chemistry
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• v.27
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• pp.56-67
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• 1984

As in many other country, the use of organic matter in Korea has long history. Farmers understand the value of organic matter as the source of plant nutrient and soil improving agent in general. Since 50 years ago, the sources of organic matter in paddy soils were compost, rice and barly straw, green manure, animal waste, fish and beancake, etc.. Application of green manures such as vetch and chinese milk vetch showed no significant effect on the yield of brown rice in paddy soil. On the other hand, the effects of compost and rice straw showed more significant on the yield of brown rice in paddy soil. Application of rice straw in rice cultivation is commonly made at different times between harvest, early spring and several weeks before transplanting. Considering the suitable paddy soil for application of rice straw under well to moderately well drained soil, the yield was pronounced more than poorly drained soil. Based on laboratory and field experimants, application of rice straw promoted the decrease of oxidation-reduction potential in well to moderately well drained soil. This results to be enhanced the release of some mineral nutrients,. such as potassium, calcium, silicon, and increase of availability of soil phosphorus. In the field experiments, results obtained from nitrogen fraction on the immobilization-mineralization of the tracer nitrogen applied in paddy soil,the amount and index of organic nitrogen incoporated in soil was more pronounced in rice straw application than control. Rice straw and its transformation products incoporated in the soil, provided the inflow of energy necessary to maintain heterotrophic microbes activities. Rice straw and its transformation products, especially soluble carbohydrate, enhanced the population of free-living heterotrophic $N_2$ - fixing microbes. Moreover, rice straw and its transformation products in paddy soil, enhanced the activities of soil enzymes such as dehydrogenase and urease.

• Journal of Environmental Science International
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• v.8 no.3
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• pp.325-330
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• 1999

This study aims to observe the inhibition of methane generation, the decomposition of organic matter, and the trend of outflowing leachate, using the simulated column of the anaerobic sanitary landfill structure of sulfate addition type which is made by adding sulfate to a current anaerobic landfill structure, and the simulated column of semi-aerobic landfill structure in the laboratory which is used in the country like Japan in order to inhibit methane from a landfill site among the gases caused by a global warming these days, and at the same time to promote the decomposition of organic matter, the index of stabilization of landfill site. As a result of this study, it is thought that the ORP(Oxidation Reduction Potential) of the column of semi-aerobic landfill structure gradually represents a weak aerobic condition as time goes by, and that the inside of landfill site is likely to by in progress into anaerobic condition, unless air effectively comes into a semi-aerobic landfill structure in reality as time goes by. In addition, it can be seen that the decomposition of organic matter is promoted according to sulfate reduction in case of $R_1$, a sulfate-added anaerobic sanitary landfill structure, and that the stable decomposition of organic matter in $R_1$ makes a faster progess than $R_2$. Moreover it can be estimated that $R_1$, a sulfate-added anaerobic sanitary landfill structure has an inhibition efficiency of 55% or so, compared with $R_2$, a semi-aerobic landfill structure, in the efficiency of inhibiting methane.

• Korean Journal of Food Science and Technology
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• v.24 no.4
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• pp.320-325
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• 1992

For natural antioxidant test, the Rhus javanica $Linn\'{e}$ was extracted by 75% ethyl alcohol and fractionated it by chloroform and ethyl acetate using separatory funnel and column chromatography. In the Rhus javanica L. extract, the effective material was disolved easily in ethyl acetate and chloroform. When 600 ppm of ethyl acetate fraction of the extract was added to palm oil and lard, AI(antioxidant index) of each oil was 1.60 and 3.90 respectively. The $CHCl_3$ and EtOAc fractions were more effective than whole extract of Rhus javanica L. The palm oil, lard and soybean oil containing different levels of the Rhus javanica L. extract were stored at $60^{\circ}C$ to compare their antioxidative activity. Peroxide value, acid value and TBA value of each oil were monitored. The Rhus javanica L. extract was very effective to retard oxidation of palm oil and lard. This result coincided with Ranimat test.