• Food Science and Preservation
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• v.15 no.3
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• pp.469-476
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• 2008

Lactic acid fermentation of peach juice was carried out by using Lactobacillus plantarum KLAB21, a strain with a high level of antimutagenic activity, When the fermentation was carried out at 25, 30, 37 and $40^{\circ}C$, the highest level in the viable counts and acid production was obtained at $37^{\circ}C$. The sterilized peach juice showed a higher level of viable counts and acid production than the non-sterilized juice. And more viable counts and acid production were observed in the juice fermented by L. plantarum KLAB21 only than that obtained by a mixed culture of L. plantarum KLAB21 and Leuconostoc mesenteroides cells. When the lactic acid fermentation was performed for 5 days, the first 3 days of fermentation resulted in an increase of the viable counts from 8.2 to of 9.2 of log cfu/mL which is the highest level, as well as a decrease of the residual reducing sugar content from 5.6 to 0.1 % Decrease in the viable counts and m significant changes in the residual reducing sugar content were observed for further fermentation up to 5 days. However, the titratable acid content increased and the pH value decreased during the fermentation for 5 days to reach the highest titratable acid content (1,98%) and the lowest pH value (3.14) after 5 days of fermentation. HPLC analysis of the organic acids showed 1,236 mg% of lactic acid and 841 mg% of galacturonic acid contents in the fermented juice which were not detected in the fresh juice before fermentation. Antimutagenic effects of $100\;{\mu}L$ of the fermented peach juice supernatant were shown to be 97.7% against MNNG(N-methyl-N'-nitro-N-nitrosoguanidine), and 58.3% against NPD(4-nitro-O-phenylenediamine) in Salmonella enterica serovar Typhimurium TA100.

• Korean Journal of Environmental Agriculture
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• v.30 no.3
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• pp.252-260
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• 2011

BACKGROUND: Currently, national biomass inventory are being established for efficient management of the potential energy sources. Among the various types of biomass, agricultural wastes are considered to take the biggest portion of the total annual biomass generated in Korea, implying its importance. However, the currently estimated amount is not reliable because the old reference data are still used to estimate total annual amount of agricultural wastes. METHODS AND RESULTS: Therefore, to provide reliable estimation data, a correct conversion factor obtained by taking into account the current situation is required. For this, the current study was conducted to provide the conversion factors for each representative 8 crop through a field cultivation study. Also conversion factors for 18 crops were calculated using the average amount of each crop produced during 2004 and 2008, subsequently; total amount of agricultural wastes generated in 2009 was estimated using these conversion factors. The total biomass of rice straw and rice husk generated in 2009 were 6.5 and 1.1 million tons, respectively, which consist 75% of the total agricultural based wastes, while the total biomass of pepper shoots and apple pruning twigs were 1.0 and 0.6 million tons, respectively. Despite the high amount of rice-based biomass, their applicability for bio-energy production is low due to conventional utilization of these materials for animal feeds and beds for animal husbandry. In addition to exact estimation of the total biomass, temporal variations in both generated amount and the type of agricultural biomass materials are also important for efficient utilization; fruit pruning twigs (January to March); barley-, been-, and mustard-related waste materials (April to June); rice-related waste (September to October). CONCLUSION(s): Such information provided in this study can be used to establish a master plan for efficient utilization of the agricultural wastes on purpose of bio-energy production.

• Korean Journal of Soil Science and Fertilizer
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• v.33 no.2
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• pp.71-78
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• 2000

Preferential flow has recently been the subject of increasing interest because these phenomena contribute to solute transport in soils. Commonly, preferential flow paths are associated with macropores or highly structured soils. We presented an analysis of the measured breakthrough curves (BTCs) of $Cl^-$ and $Cu^{2+}$ ions to test the occurrence of preferential flow in soils using miscible displacement technique under steady flow conditions. We also analyzed soil water retention curves and from this curves induced cumulative pore size distribution of undisturbed soils, which sampled from Ap1, B1, and C horizons of Songjeong series soils (the fine loamy, mesic family of Typic Hapludults). In this study, miscible displacement experiment on C horizon was excluded, because it is structureless sandy loam with saturated hydraulic conductivity of $5.2cmhr^{-1}$. The saturated hydraulic conductivity of Ap1 horizon was $2.0cmhr^{-1}$, which was about 7 times higher than that of B1 horizon ($0.27cm hr^{-1}$). Cumulative pore size distribution predicted that Ap1 horizon had more macropores (pore diameter larger than $49{\mu}m$, equivalent to -6 kpa of soil matric potential) than B1 horizon. The hydrodynamic dispersion coefficient from chloride BTCs was estimated as $1.3cm^2hr^{-1}$ for B1 and $34cm^2hr^{-1}$ for Ap1 horizon. However the retardation factors of B1 and Ap1 horizon were significantly different, i.e. 1 and 0.6, respectively, which means that there was distinct partition between mobile water and immobile phase in Ap1 horizon. The copper retardation effect of Ap1 horizon was less than that of B1 horizon, even though cation exchange capacity of Ap1 horizon was higher than that of B1 horizon. Thus, breakthrough curves of $Cl^-$ and $Cu^{2+}$ obviously showed the probability that preferential flow would occur in Ap1 horizon.

• Korean Journal of Plant Resources
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• v.17 no.3
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• pp.339-351
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• 2004

This study was conducted to evaluate the effect of phased horticultural therapy(HT) program on the experience of psychologic therapy and the development of job and social integration in the mentally handicapped persons. In this study, the mentally handicapped persons participated in HT program were chosen in disabled person's welfare institute of Jeonnam. HT program was performed twice a week with 1 hour activity for 4 months. As a results, the mentally handicapped persons participated in HT program showed high interest of horticulture and improvement of self-respect and the high satisfactory degree of HT program. Therefore, the mentally handicapped persons were showed the experience of both physical and mental therapy, improvement of self-esteem scale and sociality in HT program. Also, the application of HT program with continuously interest will be showed high improvement of physical, psychological and sentimental. In the course of this HT program progress, horticultural therapist and social welfare officer were showed the limitation of role. Therefore the leaders of group for successful HT program be required the comprehensive plan of more efficient HT program and induced technique of continuously up-phased improvements in HT program progress.

• Korean Journal of Soil Science and Fertilizer
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• v.42 no.1
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• pp.21-28
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• 2009

Detailed information on soil characteristics is of great importance for the use and conservation of soil resources that are essential for human welfare and ecosystem sustainability. This paper introduces soil inventory of Korea focusing on national soil database establishment, information systems, use, and future direction for natural resources management. Different scales of soil maps surveyed and soil test data collected by RDA (Rural Development Administration) were computerized to construct digital soil maps and database. Soil chemical properties and heavy metal concentrations in agricultural soils including vulnerable agricultural soils were investigated regularly at fixed sampling points. Internet-based information systems for soil and agro-environmental resources were developed based on 'National Soil Survey Projects' for managing soil resources and for providing soil information to the public, and 'Agroenvironmental Change Monitoring Project' to monitor spatial and temporal changes of agricultural environment will be opened soon. Soils data has a great potential of further application in estimation of soil carbon storage, water capacity, and soil loss. Digital mapping of soil and environment using state-of-the-art and emerging technologies with a pedometrics concept will lead to future direction.

• Applied Chemistry for Engineering
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• v.30 no.2
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• pp.226-232
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• 2019

The biological wastewater treatment is more eco-friendly and can be used effectively in wastewater for a variety of purposes than that of the conventional treatment. In particular, the wastewater treatment using microalgae in biological treatment processes has attracted great attention due to its ability to remove economically nutrients from wastewater and have many advantages as a renewable energy source. This study was investigated to establish the optimal growth conditions for microalga Scenedesmus obliquus. Additionally, the removal efficiencies of nutrients (N, P) and heavy metals (Cu, Zn) from the synthetic wastewater were evaluated. As a results, the optimal growth conditions were established at $28^{\circ}C$, pH 7, and light and dark cycle of 14 : 10 h. In the evaluation of nutrient removal efficiencies at each concentrations of 500, 1,000, 5,000, and 10,000 mg/L, the removal rates were 17.6~70% N and 8.4~34% P in the single treatment and 12.0~58.0% N and 3.0~40.3% P in the binary mixture treatment. In addition, the evaluation of heavy metal removal efficiencies at each concentrations of 10, 30 and 50 mg/L, the removal rates were 13.7~40.3% Cu and 10.0~30.0% Zn in the single treatment and 16.0~40.0% Cu and 12.0~20.0% Zn in the binary mixture treatment. Based on the results of the study, it appears that Scenedesmus obliquus can be used for the removal of nutrients and heavy metals from the swine wastewater.

• Journal of Nutrition and Health
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• v.54 no.1
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• pp.10-22
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• 2021

Purpose: Key Foods refers to foods that have a high contribution in the nutrient intake of individuals, and exert important effects on their health. This study was undertaken to identify Korean Key Foods, using data from the 7th Korea National Health and Nutrition Examination Survey (KNHNES). Methods: The data source for the extraction of Key Foods was the 24-hour dietary survey data obtained from the 7th KNHNES (2016-2018), and 21,271 subjects were evaluated. A total of 17 nutrients were selected as the key nutrients for identifying the Key Foods, including energy, carbohydrates, protein, lipid, dietary fiber, calcium, phosphorus, iron, sodium, potassium, vitamin A, thiamin, riboflavin, niacin, vitamin C, cholesterol, and sugars. The nutrient consumption approach was applied to generate a list of potential Key Foods. Foods included in 85% of the cumulative intake contribution from one or more key nutrients, were subsequently selected as Key Foods. Results: Of the 1,728 foods consumed by survey respondents, we extracted 728 Key Foods. These Key Foods explained 94% key nutrient intakes of the subjects. Based on the contribution rate to key nutrient intake, the top 10 Key Foods identified were multigrain rice (5.32%), plain white rice (4.23%), milk (3.3%), cabbage kimchi (2.82%), grilled pork belly (1.56%), apples (1.52%), fried eggs (1.49%), cereal (1.36%), instant coffee mix (1.21%), and sweet potatoes (1.12%). These 10 foods accounted for 23.93% total key nutrient intake of the survey respondents. Conclusion: Seven hundred and twenty-eight foods were extracted and identified as the 2020 Korean Key Foods. These Key Foods can be considered the priority foods to be analyzed for establishing a national nutrient database.

• Korean Journal of Soil Science and Fertilizer
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• v.10 no.3
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• pp.103-134
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• 1977

The physiological and biochemical role of potassium for upland crops according to recent research reports and the nutritional status of potassium in Korea were reviewed. Since physical and chemical characteristics of potassium ion are different from those of sodium, potassium can not completely be replaced by sodium and replacement must be limited to minimum possible functional area. Specific roles of potassium seem to keep fine structure of biological membranes such as thylacoid membrane of chloroplast in the most efficient form and to be allosteric effector and conformation controller of various enzymes principally in carbohydrate and protein metabolism. Potassium is essential to improve the efficiency of phoro- and oxidative- phosphorylation and involve deeply in all energy required metabolisms especially synthesis of organic matter and their translocation. Potassium has many important, physiological functions such as maintenance of osmotic pressure and optimum hydration of cell colloids, consequently uptake and translocation of water resulting in higher water use efficiency and of better subcellular environment for various physiological and biochemical activities. Potassium affects uptake and translocation of mineral nutrients and quality of products. potassium itself in products may become a quality criteria due to potassium essentiality for human beings. Potassium uptake is greatly decreased by low temperature and controlled by unknown feed back mechanism of potassium in plants. Thus the luxury absorption should be reconsidered. Total potassium content of upland soil in Korea is about 3% but the exchangeable one is about 0.3 me/100g soil. All upland crops require much potassium probably due to freezing and cold weather and also due to wet damage and drought caused by uneven rainfall pattern. In barley, potassium should be high at just before freezing and just after thawing and move into grain from heading for higher yield. Use efficiency of potassium was 27% for barley and 58% in old uplands, 46% in newly opened hilly lands for soybean. Soybean plant showed potassium deficiency symptom in various fields especially in newly opened hilly lands. Potassium criteria for normal growth appear 2% $K_2O$ and 1.0 K/(Ca+Mg) (content ratio) at flower bud initiation stage for soybean. Potassium requirement in plant was high in carrot, egg plant, chinese cabbage, red pepper, raddish and tomato. Potassium content in leaves was significantly correlated with yield in chinese cabbage. Sweet potato. greatly absorbed potassium subsequently affected potassium nutrition of the following crop. In the case of potassium deficiency, root showed the greatest difference in potassium content from that of normal indicating that deficiency damages root first. Potatoes and corn showed much higher potassium content in comparison with calcium and magnesium. Forage crops from ranges showed relatively high potassium content which was significantly and positively correlated with nitrogen, phosphorus and calcium content. Percentage of orchards (apple, pear, peach, grape, and orange) insufficient in potassium ranged from 16 to 25. The leaves and soils from the good apple and pear orchards showed higher potassium content than those from the poor ones. Critical ratio of $K_2O/(CaO+MgO)$ in mulberry leaves to escape from winter death of branch tip was 0.95. In the multiple croping system, exchangeable potassium in soils after one crop was affected by the previous crops and potassium uptake seemed to be related with soil organic matter providing soil moisture and aeration. Thus, the long term and quantitative investigation of various forms of potassium including total one are needed in relation to soil, weather and croping system. Potassium uptake and efficiency may be increased by topdressing, deep placement, slow-releasing or granular fertilizer application with the consideration of rainfall pattern. In all researches for nutritional explanation including potassium of crop yield reasonable and practicable nutritional indices will most easily be obtained through multifactor analysis.