• Food Science and Preservation
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• v.22 no.3
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• pp.408-420
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• 2015

This study investigated the effect of heat treatment conditions on the quality and antioxidant activities of Korean traditional actinidia (Actinidia arguta) cultivars puree. Heat treatment on actinidia puree was conducted at $70{\sim}90^{\circ}C$ for 1 min to 5 mins, while a control sample of the actinidia puree was prepared without heat treatment. In all the samples, except for the sample treated at $90^{\circ}C$ for 5 mins, pH and Brix degree was not dramatically changed. Pulp content decreased with increasing temperature and time. L and the a value of color increased with increasing temperature and time. However, the b value showed a reverse tendency with L and the a value. Viscosity and gumminess increased as heat temperature and time increased, though cohesiveness was not significantly changed depending on temperature and time. Coliform and yeast were not detected on all samples and the number of aerobic bacteria and mold decreased as temperature and time increased. Vitamin C and total phenolic content of the puree was not changed for 1, 3, and 5 mins at $70^{\circ}C$ and for 1 and 3 mins at $80^{\circ}C$, but significantly decreased with increasing time at $90^{\circ}C$. Furthermore, the antioxidant activities of the puree, such as DPPH radical scavenging activity, ABTS radical scavenging activity, and FRAP (ferric reducing antioxidant power) showed a similar tendency with total phenolic content.

• Food Science and Preservation
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• v.18 no.5
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• pp.755-763
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• 2011

This study was conducted to monitor the quality characteristics Citrus unshiu ethanolic extracts by a response surface methodology. In extraction conditions based on the central composite design with variations in ethanol concentration (0~100%), extraction temperature($35\sim95^{\circ}C$), and ratio of solvent to sample(20 mL/g). The maximum value of yield was 36.31% at $93.18^{\circ}C$, 67.13% of ethanol concentration. The extraction yield and total polyphenol content were improved with the increase of ethanol concentration than extraction temperature. Total flavonoid content was improved with the increase of extraction temperature than ethanol concentration. The coefficients of determinations($R^2$) were 0.8646(p<0.1) and 0.9153(p<0.05) in electron donating ability and hesperidin content, respectively. Estimated conditions for the maximized extraction including yield, total polyphenol content, total flavonoid content, electron donating ability, and hesperidin content were 55~73% in ethanol concentration, $89\sim95^{\circ}C$ in extraction temperature, and 20 mL/g in ratio of solvent to sample.

• Korean Journal of Food Science and Technology
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• v.33 no.6
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• pp.745-752
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• 2001

Wild edible plants are consumed as raw or processed. Analytical data for raw biologically functional compounds were relatively well established. The changes on functional compounds during processing are, however, not well studied. This study was carried out to investigate the change of the quality of wild edible plants, Chamchwi, blanched at various conditions. Samples were blanched at the salt concentration of 0%, 1% or 2% for 1, 3, and 5 minutes each. The biologically active compounds, vitamin C, ${\beta}-carotene$, chlorophyll, flavonoids, polyphenols and minerals were analyzed. The concentration of vitamin C in Chamchwi did not show any significant change under various blanching conditions. Beta-carotene in Chamchwi was not significantly affected by blanching time. Higher salt concentration of blanching water, however, resulted in the increased concentration of ${\beta}-carotene$ in the blanched Chamchwi. Higher salt concentration of blanching water also reduced the loss of total flavonoids and total polyphenols from the blanched Chamchwi. The change of colors in the blanching water seemed to be corresponding to those of total flavonoids and total polyphenols concentrations in the blanching water.

• Journal of the Korean Society of Food Science and Nutrition
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• v.46 no.11
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• pp.1366-1372
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• 2017

This study compared the physicochemical quality characteristics of the Omija beverage for 36 weeks (9 months) depending on the storage container and storage temperature. From 3 weeks of storage, the optical density showed a significant difference according to the storage container, and the soluble solid contents showed a significant difference according to the storage container, storage temperature, and storage container${\times}$temperature. The total polyphenol and total acidity decreased slightly in the late storage period at all transparent and brown bottle treatments but the pH increased slightly. Generally, changes in the quality characteristics of Omija beverage at $4^{\circ}C$ storage were less than that at $20^{\circ}C$ and $36^{\circ}C$ storage. Correlation analysis of each factors, optical density, soluble solid content, total polyphenol, pH, and total acidity showed a positive correlation with each item according to the storage period. The storage period, particularly the transparent bottle treatment, appeared to have a significant impact on reducing the optical density. A few quality changes were observed after the brown bottle treatment for 36 weeks. In addition the stability according to the storage temperature was confirmed in each treatment. The brown bottle treatment is effective in maintaining the quality of Omija beverage for 36 weeks.

• Korean Journal of Ecology and Environment
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• v.48 no.2
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• pp.115-121
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• 2015

In order to assess the water quality of Kumho river using Diatom Assemblage Index to organic water pollution (DAIpo) and to campare from the previous water quality, 5 sites in Kumho river were selected and assessed total of 6 times, every April and September from April 2010 to September 2012. As a result, 116 taxa were found in 2 Order, 3 Suborder, 7 Families, 26 Genera, 103 species and 13 varieties. Saprophilous species of 10 dominant species including Achnanthes minutissima, were increased as going to downstream sites. Correlation coefficients (r) between epilithic diatom communities and physicochemical factors were from - 0.62 to 0.71. Correlation coefficients (r) between TN and diatom indices (DAIpo, TDI) were 0.57 and 0.65, respectively. Therefore, epilithic diatom communities were greatly influenced by TN. The Correlation between DAIpo and TDI measured to be high in correlation coefficient (r=0.62) from the result of correlation analysis. Mean of DAIpo values ranged between 37.24~74.98 and decreased as going to downstream sites. Saprobic level was estimated as ${\beta}$-oligosaprobic at st. 1, ${\alpha}$-oligosaprobic at st. 2 and ${\beta}$-mesosaprobic at st. 3. But st. 4 and 5 which were ${\alpha}$-mesosaprobic and polysaprobic in the previous results, were improved as ${\beta}$-mesosaprobic. The RPId, general assessment of the water quality using DAIpo, was 52.27, which means the water quality of Kumho river was middle level.

• Korean Journal of Ecology and Environment
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• v.42 no.2
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• pp.212-220
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• 2009

In this study, we analyzed fish compositions and ecological characteristics such as trophic guilds and tolerance guilds in association with water quality characteristics in Masan Reservoir during November 2008. Total number of species were 12 species (6 families) and the dominant species were Zacco platypus, Hemiculter eigenmanni, and Pseudorasbora parva. We found three Korean endemic species and one exotic species, Carassius cuvieri. According to the analysis of ecological indicator characteristics, relative proportion of tolerant and omnivore species was 98% of the total indicating that probably, the fauna was influenced by physical habitat disturbance and physicochemical degradations. Fish distribution analysis along with littoral zone showed that the most fishes (${\sim}$95%) were observed in the littoral zone where emerged macrophytes were well developed. Also, substrate analysis indicated that the most species were found near silt area (11 species, 91.7%), so that the significant differences were found between the substrate types. Analysis of water quality indicated that concentrations of total phosphorus (TP) and chlorophyll-a (ChI-a) as a lake trophic indicator were judged as eutrophic states, respectively and COD as an indicator of organic matter pollution averaged 10.9 mg $L^{-1}$. Based on the water quality, this system were influenced by the nutrient enrichments and organic matter. The degradations of water quality in Masan Reservoir resulted in trophic compositions of fish (increase of omnivore species) and the dominance of tolerant fish. This Monitoring data may contribute changes of fish fauna and compositions in relation to habitat modifications and chemical water quality degradations in the future.

• Journal of agriculture & life science
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• v.43 no.2
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• pp.1-8
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• 2009

The limestone area covers the narrow range of the Korean Peninsula, and it consists of a peculiar ecosystem and topography. Therefore, this study on limestone area was carried out classification of vegetation type, physicochemical properties of forest soils and correlation between environment factors and vegetation types in order to furnish fundamental data for the forest management of limestone area. Forest vegetation was classified into two community groups such as Quercus variabilis community group and Quercus mongolica community group, and it was classified into eight vegetation units. Soil texture of survey sites showed largely silt loam and soil pH indicated the value of mean 7.55 in the A layer of soil profile. Content of exchangeable cation such as calcium ion ($Ca^{2+}$) and magnesium ion ($Mg^{2+}$) showed $26.04cmol_{c}/kg$ and $2.93cmol_{c}/kg$, respectively, which was about ten times higher than average of other regions of Korea. According to corelation between environmental factors and vegetation units, Q. variabilis community group was positively correlated to soil pH, slope degree and the rate of bare rock, and content of calcium ion ($Ca^{2+}$), and then Q. mongolica community group was positively correlated to altitude, respectively.

• Journal of the Korean Society of Child Welfare
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• no.26
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• pp.7-30
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• 2008

The survival rate of children with cancer has increased significantly from less than 30% in 1960s to 75% during the recent years with the development of modern medical technologies. As a result, the cancer of children today is no longer classified as incurable diseases. Rather, it is recognized as a chronic illness. However, children with cancer are still suffering from physical and psychosocial ailments caused by long-term hospitalization. In particular, teenagers are more likely to be affected by these problems because of interests on one's appearance and peer relationships This study investigated the relationship of the level of body distortion and disease adjustment of children with cancer, and how demographic factors, disease factors, and the level of body distortion affect disease adjustment. Data were collected between October 22, 2007 and November 16, 2007 and the total respondents consisted of 82 children, ages 10 to 18. SPSS 12.0 with descriptive statistics, t-test, correlation and multiple regression were used for data analysis. The results showed that the factors which influence the disease adjustment of children with cancer were age, school enrollment, and the level of body distortion. The result of this study has major implications for the government to provide support for children with cancer to stay in school. Additionally, programs that assist children to build positive body images need to be developed in accordance with their ages and psychosocial characteristics.

• Korean Journal of Ecology and Environment
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• v.55 no.2
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• pp.175-183
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• 2022

In this study, 46 reservoirs in South Korea were characterized based on heavy metal concentration in sediments. We analyzed the relationship between heavy metal concentrations, physicochemical water quality and hydromorphological factors in each reservoir. Study reservoirs were classified into five groups of reservoirs, by hierarchical cluster analysis based on the similarities of heavy metal concentration. Group 1 had the most severe sediment heavy metal contamination among the groups, whereas Groups 2 and 3 showed low levels of heavy metal contamination. Group 4 displayed high value of Ni, and Group 5 showed high contamination of Pb, Cu, Cr, Ni, and Hg. Groups 1 and 5, which had high concentration of heavy metals in sediments, showed a high density of mines in the catchment of reservoirs. Heavy metal concentration was high in reservoirs with large capacity or the ones located at higher elevation, and also highly related with number of mines in the catchment of reservoir. This study can contribute to the systematic management of sediment heavy metals in reservoirs.

• Korean Journal of Soil Science and Fertilizer
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• v.25 no.3
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• pp.270-274
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• 1992

This study was observed to find out the relationship of soil microorgaism physico-chemical properties and yields on the continuous cultivation of peanuts soil in the difference 20 farmes field located in Gochang, Chonbuk area. The results obtained was summarized as follows : 1. Soil hardness and volume of soild and liquid of peanut continuous cultivation soil were higher than those of one year cultuvation. 2. The exceeding optimum level of phosphorus and potassium appeared factors affecting and reduction of peanut continuous cultivation soil. 3. Number of microorgaisms in continuous cultivation soil was high but the ratio of bacteria/fungi (B/F) and actinomycetes/fungi (A/F) ratio were low. 4. The number of soil nematodes in continuous cultivation soil were higher than that of alternative cultivation soil.