• Korean Journal of Weed Science
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• v.8 no.1
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• pp.15-22
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• 1988

In this experiment, interactions between light and other factors such as chilling, alternating temperature, moisture, content, oxygen, and seed coat which affect germination of Oenothera lamarckiana Ser. seed were investigated to study the physiological effects of light on the germination. Light induced the initial stage of seed germination before radical protrusion by affecting embryo rather than seed coat even under anaerobic condition or low water potential (-18 bars). This light effect on germinability of seed was suppressed by blue light irradiation and the effect was increased with increment of blue light intensity and irradiation time. However, the blue light effect was reversible. Chilling, alternating temperature, softening of seed coat and light showed promotive interaction in the induction of seed germination. Irradiation of filtered light (monochrome), however, reduced chilling effect on germination. Hydrogen-ion concentration and gibberellic acid treatment had no effect on light or dark germination.

• Horticultural Science & Technology
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• v.31 no.1
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• pp.1-7
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• 2013

In this study, the resistance to ozone and characteristics of ozone-induced damage were investigated on the perennial ground cover plant species. Sedum kamtschaticum and Hosta longipes were exposed to $200{\mu}g{\cdot}kg^{-1}$ ozone for 8 hours per day (from 08:00 to 16:00) in the naturally irradiated phytotron. The extent of ozone-induced damage was measured through the analysis of physiological parameters, such as water use efficiency (WUE), chlorophyll content (Chl. a, Chl. b, Chl. a + b, and Chl. a/b ratio), carotenoid contents, and the induction of reactive oxygen species (ROS). Ozone exposure significantly reduced the daytime WUE in both species. The contents of chlorophyll and carotenoid were also decreased and ROS, such as hydrogen peroxide ($H_2O_2$) and superoxide radical ($O_2{^-}$) were accumulated after ozone exposure. The above results of this study suggested that S. kamtschaticum is more resistant to atmospheric ozone than Hosta longipes. Considering its fast responses to ozone, it was also assumed that Hosta longipes can be used as an indicator plant of an increase in atmospheric ozone concentration.

• Korean Journal of Food Science and Technology
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• v.6 no.4
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• pp.231-240
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• 1974

The growth of a mixed yeast culture consisting of Canda tropicalis var. KIST 76 and Tricosporon cutaneum KIST 76-H was compared with that of pure cultures under pilot plant conditions. The mixed culture was judged stable based on the nearly constant ratio of the two organisms at the completion of fermentation. We obtained higher cell yields, protein content and productivity in the mixed culture on n-paraffin than the pure culture of C. tropicalis var. KIST 76. T. cutaneum KIST 76-H did not grow on n-paraffin medium. With the batch cultivation of mixed organisms on n-paraffin, the specific growth rates during the exponential growth phase were 0.24-0.33 $hr^{-1};$ cell yields were 96-106% and productivities were 2.9-3.6g/l. hr. The cells obtained contained 55-58% crude protein and 5.5-6.3% lipid. The critical value of dissolved oxygen concentration Ccrit. and saturation constant, km, are approximately 1.5 ppm and 0.228 ppm respectively. Also we established the optimal conditions for the mixed culture in batch fermentation.

• Korean Journal of Food Science and Technology
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• v.52 no.2
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• pp.138-143
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• 2020

Black chokeberry (Aronia melanocarpa) has been suggested to exert antioxidant and anti-inflammatory effects due to its high polyphenol content. However, the mechanisms underlying the effects of black chokeberry on the alterations of nuclear factor E2-related factor 2 (NRF2) and nuclear factor κB (NF-κB) in macrophages have not been thoroughly studied. In this study, we investigated the protective effects of polyphenol-rich black chokeberry extract (CBE) against lipopolysaccharide (LPS)-induced oxidative stress and inflammation in RAW 264.7 macrophages. CBE significantly attenuated the increase of cellular reactive oxygen species (ROS) levels and the nuclear translocation of NRF-2 in LPS-stimulated macrophages. The mRNA abundances of Nrf2 and its downstream antioxidant genes were significantly decreased in LPS-stimulated macrophages. The LPS-induced mRNA expression of proinflammatory cytokines was significantly inhibited by reducing the nuclear translocation of NF-κB by CBE. These data suggest that black chokeberry may be used for the prevention of oxidative stress and inflammation-associated disease.

• Korean Journal of Food Science and Technology
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• v.32 no.2
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• pp.246-251
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• 2000

This study was investigated to compare the changes of antioxidative compounds in sesame oil with roasting temperature$(110^{\circ}C{\sim}230^{\circ}C)$. Lightness was decreased markedly over $170^{\circ}C$. In the changes of lignan contents, 7 different lignans unchanged up to $170^{\circ}C$ and sesamolin and sesamin decreased markedly, whereas sesamol, unknown1, unknown3 increased drastically at the higher temperatures. In tocopherol contents, ${\gamma}-tocopherol$ decreased from 70.59 mg% in unroasted oil to 33.87 mg% at $220^{\circ}C$, and to 26.73 mg% at $230^{\circ}C$. In the result of AOM(active oxygen method) test carried out at $120^{\circ}C$ for evaluating oxidative stability, the induction period of unroasted oil was 4.12 hrs and that of roasted oils was increased with roasting temperature (induction period at $220^{\circ}C$ was 27.9 hrs.). From the above results, it was confirmed that correlation coefficient between oxidative stability and lightness is -0.993 and that between oxidative stability and sesamol content is 0.934 above $170^{\circ}C$. Therefore its remarkable oxidative stability with the roasting temperature, might be considered to be due to the increase of sesamol, other lignans(unknown 1, unknown 3).

• Economic and Environmental Geology
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• v.38 no.1
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• pp.91-99
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• 2005

Acid Rock Drainage(ARD) is the product formed by the atmospheric(i.e. by water, oxygen and carbon dioxide) oxidation of the relatively common iron-sulphur mineral pyrite($FeS_2$). ARD causes the acidification and heavy metal contamination of water and soil and the reduction of slope stability. In this paper the generation characteristics and the prediction of ARD of various cut slopes were studied. An attempt to classify the rocks into several groups according to their acid generation potentials was made. Acid Base Accounting(ABA) tests, commonly used as a screening tool in ARD predictions, were performed. Fourteen rock samples were classified into PAF(potentially acid forming) group and four rock samples into NAF(non-acid forming) group. The chemical analysis of water samples strongly suggested that ARD with high content of heavy metals and low pH could pollute the ground water and/or stream water.

• Korean Journal of Environmental Biology
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• v.35 no.4
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• pp.566-572
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• 2017

For four times, zooplankton collection were conducted seasonally in October 2015-July 2016 at five sites located in the wet lands of the lower Han River, ie., Si-am, Sung-dong, Gong-reung stream, San-nam and Jang-hang. A total of 46 species of zooplankton were collected, which comprise 25 species of rotifers, seven cladocerans, ten copepods, and one species of nematod, ostracod and decapod, respectively. No brackish and marine species were distributed except for two species of brackish water copepods. Prosperity in the species number of 15 species was observed in October at Sung-dong and Jang-hang. The maximum abundance was recorded in March at Si-am with $8,000indiv.\;L^{-1}$ with the explosion of Brachionus calyciflorus. Other sites also showed high abundances in March with the abundance higher than $5,000indiv.\;L^{-1}$. Except in March, the abundance levels were recorded as less than some hundred $indiv.\;L^{-1}$ throughout the study. Species diversity varied between 0.4-1.8. The gut contents of the copepodite showed that various diatoms might be their major food items, and lots of unidentified materials were also observed. The environmental conditions of water temperature, pH and dissolved oxygen content showed to vary $10.1-28.2^{\circ}C$, 7.1-8.6 and $4.5-11.0mg\;L^{-1}$, respectively.

• Journal of Yeungnam Medical Science
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• v.6 no.1
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• pp.121-131
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• 1989

The temperature-corrected values of blood gas analysis were compared to uncorrected values in 40 cases of open heart surgery under moderate hypothermic cardiopulmonary bypass. The results were as follows. 1. The corrected value of pH was significantly higher than uncorrected value, and it's relationship was ${\Delta}pH=-0.015$ ${\Delta}Temp+0.005$(r=0.81, P<(0.01). 2. The corrected value of $PCO_2$ was lower than uncorrected value, and it's relationship was ${\Delta}PCO_2=1.11$ ${\Delta}Temp+1.81$(r=0.50, P<0.01). 3. The corrected value of $PO_2$ was lower than uncorrected value, and it' s relationship was ${\Delta}PO_2=5.21$ ${\Delta}Temp-1.45$(r=0.32, P<0.01). But there was no clinical significance. 4. The corrected values of $HCO_{3^-}$, base excess, $CO_2$ content and oxygen saturation were similar with uncorrected values. In summery, the values of pH and $PCO_2$were significantly changed by temperature-correction. Because of the neutral point of water (pH=pOH) rises as temperature falls and it change in parallel with the changes in blood pH, a corrected pH of 7.4, $PaCO_2$ of 40mmHg during deep hypothermia would reflect a profound respiratory acidosis. Therefore, the use of the uncorrected value at $37^{\circ}C$ is more preferable and valid means of assessing acid-base management regardless of actual patient temperature.

• The Korean Journal of Food And Nutrition
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• v.32 no.5
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• pp.462-472
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• 2019

The purpose of this study was to demonstrate the quality characteristics of Brassica juncea cultivated in Jeongseon (BJJ), South Korea. We analyzed the nutritional components and antioxidant activity of BJJ. As a result of the free sugar analysis, the contents of glucose and fructose in BJJ were $0.29{\pm}0.02g/100g$ and $0.10{\pm}0.00g/100g$, respectively. The major fatty acids were palmitic acid, octadecenoic acid and stearic acid. The palmitic acid was the highest at 31.22% of all fatty acids. The major minerals were identified as Ca, P, K, Mg and Na. The contents of vitamin $B_1$, vitamin $B_2$, vitamin $B_6$, vitamin C and vitamin E in BJJ were $0.02{\pm}0.00mg/100g$, $0.087{\pm}0.01mg/100g$, $0.02{\pm}0.00mg/100g$, $0.56{\pm}0.06mg/100g$ and $0.20{\pm}0.03mg\;{\alpha}-TE/100g$, respectively. As a result of the free amino acid analysis, total amino acid contents in BJJ were $2,801.21{\pm}115.38mg/100g$. L-proline content was the highest ($744.30{\pm}119.06mg/100g$) in BJJ. BJJ extract inhibits reactive oxygen species production in 3T3-L1 adipocytes. Also, BJJ extract exhibits a protective effect on oxidative stress in $H_2O_2$-induced human dermal fibroblast. These results indicate that BJJ comprises various valuable nutrients which can be used as functional food ingredients.

• Korean Journal of Food Science and Technology
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• v.51 no.5
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• pp.503-508
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• 2019

To evaluate the protective effect of Ecklonia cava on ultra-fine dust ($PM_{2.5}$)-induced cytotoxicity, we investigated the in vitro antioxidant activity and cell viability after exposure to $PM_{2.5}$. E. cava was extracted using water and 80% ethanol, and antioxidant activity was determined using the 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS)/2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging and lipid peroxidation inhibition assays. The 80% ethanol extract showed relatively higher antioxidant activity than the water extract. The cell protective effects were determined by measuring the intracellular reactive oxygen species (ROS) content and viability of nasal epithelial (RPMI-2650), lung epithelial (A549), and brain neuroblastoma (MC-IXC) cells. Results showed that the 80% ethanol extract inhibited ROS production more than the water extract. In contrast, both extracts showed similar effects on cell viability in the $PM_{2.5}$-induced cell death assay. Thus, Ecklonia cava may act as an effective resource for preventing $PM_{2.5}$-induced cytotoxicity in nasal, lung, and brain cells.