• Journal of Environmental Science International
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• v.18 no.10
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• pp.1065-1070
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• 2009

Experimental design for ecological restoration approach was investigated from the P' company's slag dumping area with higher pH value. The degree of pH recovery was measured by the injection of carbon dioxide from the LNG exhaust gas, and the residual carbon, for example, calcium and carbonate which can be controlled by artificial seaweed beds. The degree of adaptability from 3 algaes (Undaria pinnatifida, Sargassum horneri and Ecklonia stolonifera) and uptake nutrient function of Ecklonia stolonifera chosen in the first treatment were measured in the laboratory to determine the transplanting algae in artificial seaweed beds. The higher value of pH was decreased to 7.0~8.5 by injection of LNG exhaust gas with flow rate $20\;m^3/min$. In the experiment design at laboratory, the upper part of frond of Undaria pinnatifida and Sargassum horneri began to decay, and the color changed after 10 days. However, those of Ecklonia stolonifera were after 14~20 days. The uptake rate of nutrient from Ecklonia stolonifera was higher than those of other algaes, and those was similar pattern in the control (e.g. seawater); The DIN concentration uptake of Ecklonia stolonifera was $1.88\;{\mu}g/L/hr$ avg. in leachate, but $2.19\;{\mu}g/L/hr$ avg. in seawater. However, the ${PO_4}^3$-P concentration uptake was $0.18\;{\mu}g/L/hr$ avg. in leachate, but $0.31\;{\mu}g/L/hr$ avg. in seawater. These result indicated Ecklonia stolonifera uptaked these nutrients in the leachate as well as in seawater, and it may suggested for this species to transplant for constructing artificial seaweed beds.

• Horticulture, Environment, and Biotechnology : HEB
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• v.59 no.6
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• pp.775-786
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• 2018

To test the hypothesis that humic acid (HA), anaerobically digested pig slurry filtrate (APS), and their combination would differently affect the chemical speciation and extractability of metals (cadmium, copper, and zinc) and their uptake by plants, we conducted a pot experiment using wormwood in two texturally contrasting soils (sandy loam and clay loam) collected from a field near an abandoned Cu mine. Four treatments were laid out: HA at $ 23.5g\;kg^{-1}$ (HA), APS at $330mL\;kg^{-1}$ (APS), HA at $ 23.5g\;kg^{-1}$ and APS at $330mL\;kg^{-1}$ (HA + APS), and a control. Each treatment affected the chemical speciation and mobility of the metals, and thereby resulting in variable patterns of plant biomass yield and metal uptake. The APS supported plant growth by increasing nutrient availability. HA supported or hindered plant growth by impacting the soil's water and nutrient retention capacity and aeration, in a soil texture-dependent manner, while consistently enhancing the immobilization of heavy metals. Temporal increases in whole-plant dry matter yield and metal accumulation suggested that the plants were capable of metal hyperaccumulation. The results were discussed in terms of the mobility of metals and plant growth and corroborated by the $^{15}N$ recovery of soil- and plant-N pools under H and HS treatments. Therefore, for effective phytoremediation of polluted soils, an appropriate combination of plant growth promoters (APS) and chelating agents (HA) should be predetermined at the site where chemical stabilization of pollutants is desired.

• Korean Journal of Organic Agriculture
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• v.23 no.4
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• pp.829-846
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• 2015

This study was conducted to determine the effects of organic fertilization rates on the nutrient accumulation and recovery in radish (Raphanus sativus L.) as well as growth and yield of radish in Jeju island. An understanding the relationships between organic fertilization rate, crop nutrient recovery and crop yield can assist in making organic fertilizer recommendation which balances crop value and environmental risk in organic cultivation. Nitrogen (T-N), phosphate ($P_2O_5$) and potassium ($K_2O$) were applied at 0, 115-35-40, 230-70-80 (standard application rate), 460-140-160, 230-200-100 (recommended application rate) and 158-53-35 kg/ha (customary application rate), respectively as the broadcast application of mixed organic fertilizer (N 4.5% - $P_2O_5$ 1.5% - $K_2O$ 1%) in combination with langbeinite ($K_2O$ 22%), 100% at sowing period. The organic fertilizer was made of organic materials like oil cakes. Total yield of radish, as fresh weight of roots, increased with increasing organic fertilizer doses to a maximum at rate of standard or soil-testing application. Nitrogen, phosphate and potassium accumulations of radish increased curvilinearly with increasing organic fertilization rate to a maximum at rate of N 460 - $P_2O_5$ 140 - $K_2O$ 160 kg/ha. However, nitrogen, phosphate and potassium use efficiency of applied organic fertilizer decreased curvilinearly or linearly with increasing organic fertilization rate. Application of organic fertilizer in combination with langbeinite (as a potassium source) had significant effect on the yield of radish. Organic fertilization on a basis of standard or soil-testing application rate is recommended for maximun radish yield in organic cultivation.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.50 no.1
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• pp.16-21
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• 2005

This study was conducted to establish the elaborate nitrogen fertilization method to enhance N use efficiency in direct-seeded rice on flooded paddy. The nitrogen uptake by rice plants was insignificant until 25 days after seeding, and increased gradually thereafter. During this early growth stage, rice plants absorbed only the $4\%$ of basal applied N, while the $45\%$ of N fertilizer remained in the paddy soil. The absorption of basal N by rice plants was almost completed at 46 days after application. Nitrogen top-dressed at 5-leaf stage was well matched to crop nutrient demand, so it could be absorbed so actively in 8days after application. As a result, we could cut down the amount of N fertilizer to $36\%$ of the basal N level without significant difference in yield. Plant recoveries of fertilizer $^{15}N$ applied with different application timings were $7.8\%$ for basal, $9.4\%$ for 5-leaf stage, $17.1\%$ for tillering stage, and $23.4\%$ for panicle initiation stage, respectively. When urea was applied with nitrogen fertilization practice based on basal incorporation (BN), plant recovery of $^{15}N$ at harvest was $31.0\%$, which was originated from $13.7\%$ for grain, and $21.3\%$ of the fertilizer $^{15}N$ remained in the soil, and the rest could be uncounted. Plant recovery of fertilizer $^{15}N$ applied with nitrogen fertilization practice based on topdressing at 5-leaf stage (TN), where N rate was reduced by $18\%$ compared with BN, was $35.1\%$ (grain $15.6\%$), and $19.9\%$ of the fertilizer $^{15}N$ remained in the soil, and the rest could be uncounted. TN showed a higher $^{15}N$ recovery than BN because it was to apply N fertilizer at a time to well meet the demand of rice plant direct-seeded on flooded paddy. We concluded that TN would be the nitrogen fertilization method to enhance N use efficiency in direct-seeded rice on flooded paddy.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.47 no.2
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• pp.137-141
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• 2002

Decomposition of green manure is necessary for the nutrient supply in farm soil. Hairy vetch as a green manure is superior to other winter legumes in terms of wintering ability and N accumulation. This experiment was carried out to investigate the decomposition and N release of hairy vetch and its effect on rice production as the following crop in paddy field. Decomposition of hairy vetch placed by soil depth of 0, 10 and 20cm at transplanting time was investigated by mesh bag method, which was enclosed chopped residue in mesh bags. The fate of $^{15}$ N derived from $^{15}$ N-labeled hairy vetch was investigated at harvest in three levels of N fertilization. Grain yield of the transplanted paddy rice cultured with hairy vetch as starter N were compared with that of applying urea as starter N in the field. Hairy vetch residue decomposed very rapidly both in transplanted and dry-seeded paddy field. In transplanted paddy field, hairy vetch residue lost 72-81 % and 86-90% of its weight after one and five month, respectively, as affected by incorporation depth. The C/N ratio of the decomposing vetch residue increased sharply during the early stages and after then, decreased slowly. The amounts of N and P released from the vetch were about 90% and 97% of initial content after one month, respectively. Recoveries of hairy vetch-$^{15}$ N by rice plant were 30.6, 34.6 and 35.7% in 0, 6 and 12 kg urea-N 10 $a^{-l}$ application, respectively, indicating that N fertilization increased the recovery of hairy vetch. $^{15}$ N. Hairy vetch residue incorporated as starter maintained significant N $H_4$$^{+}$-N concentration in soil water of plow layer until effective tillering stage. Grain yield in the plot applied with hairy vetch was not significantly different from that in the plot with urea. We concluded that hairy vetch incorporation could substitute starter N fertilization and showed possibility to reduce N amount of top-dressing.g.g.

• Korean Journal of Environment and Ecology
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• v.26 no.1
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• pp.67-73
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• 2012

This study has compared the different types of forest fire sites and the unburned site at Samcheuk-si Gangwon-do by assessing the amount of litter production, nutrient concentration returned to forest floor from July 2007 through October 2010. The research showed that the average amounts of litterfall produced in the unburned site, the crown fire site(C-1), the crown fire site(C-3) and the ground fire site(G-2) were $7.74{\pm}2.56$, $1.17{\pm}0.67$, $2.97{\pm}0.44$ and $2.92{\pm}0.42ton{\cdot}ha^{-1}{\cdot}yr^{-1}$, respectively. In the unburned site, the average amounts of total nitogen(T-N), total phosphorus(T-P), potassium(K), calcium(Ca) and magnesium(Mg) returned to the forest floor were $22.20{\pm}12.43$, $1.16{\pm}0.46$, $2.68{\pm}1.44$, $16.22{\pm}4.69$ and $1.36{\pm}0.32 kg{\cdot}ha^{-1}{\cdot}yr^{-1}$, respectively whereas those in the crown fire site(C-1) were $3.73{\pm}2.31$, $0.10{\pm}0.09$, $0.27{\pm}0.20$, $2.75{\pm}2.58$ and $0.24{\pm}0.27 kg{\cdot}ha^{-1}{\cdot}yr^{-1}$, respectively. This study showed that the nutrient content returned to forest floor was higher in the following order: unburned site(Un) > crown fire site(C-3) > ground fire site(G-2) > crown fire site(C-1).

• Journal of Environmental Science International
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• v.24 no.10
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• pp.1253-1264
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• 2015

This study assessed the fertilizing value of struvite deposit recovered from swine wastewater in cultivating Chinese cabbage. Struvite deposit was compared with commercial fertilizers: complex, organic and compost to evaluate the fertilizing effect of struvite deposit. Laboratory pot test obviously presented that the struvite deposit more facilitated the growth of Chinese cabbage than organic and compost fertilizers even though complex fertilizer was the most effective in growing Chinese cabbage. It was revealed that the growth rate of Chinese cabbage was simultaneously controlled by phosphorus (P) and potassium (K). Also, the nutrients such as nitrogen (N), P, K, calcium (Ca) and magnesium (Mg) were abundantly observed in the vegetable tissue of struvite pot. Specifically, P was the most abundant component in the vegetable tissue of struvite pot. Meanwhile, the utilization of struvite as a fertilizer led to the lower accumulation of chromium ($Cr^{6+}$) than other pots, except for compost fertilizer pots, and no detection of cadmium (Cd), arsenic (As) and nickel (Ni) in the Chinese cabbage. The experimental results proved that the optimum struvite dosage for the cultivation of Chinese cabbage was 2.0 g struvite/kg soil. On the basis of these findings, it was concluded that the struvite deposits recovered from swine wastewater were effective as a multi-nutrient fertilizer for Chinese cabbage cultivation.

• Microbiology and Biotechnology Letters
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• v.9 no.2
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• pp.91-97
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• 1981

A thermophilic soil isolate Bacillus sp. Y-127 was selected for the production of thermostable amylase. The strain was used for the enzyme production and the thermostable amylase was characterized. The optimum cultural conditions for the enzyme production were 6$0^{\circ}C$ at pH 7.0 for 32 hours using a mineral medium containing 2% soluble starch and 0.2% yeast extract. The extra-cellular enzyme was purified about 123-folds with about 6% recovery. The purified enzyme was stable at pH between 4.0 and 7.0, and temperature up to 6$0^{\circ}C$.

• Biomolecules & Therapeutics
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• v.28 no.3
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• pp.240-249
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• 2020

Despite the therapeutic effect of mesenchymal stem cells (MSCs) in ischemic diseases, pathophysiological conditions, including hypoxia, limited nutrient availability, and oxidative stress restrict their potential. To address this issue, we investigated the effect of melatonin on the bioactivities of MSCs. Treatment of MSCs with melatonin increased the expression of peroxisome proliferator-activated receptor gamma coactivator-1 alpha (PGC-1α). Melatonin treatment enhanced mitochondrial oxidative phosphorylation in MSCs in a PGC-1α-dependent manner. Melatonin-mediated PGC-1α expression enhanced the proliferative potential of MSCs through regulation of cell cycle-associated protein activity. In addition, melatonin promoted the angiogenic ability of MSCs, including migration and invasion abilities and secretion of angiogenic cytokines by increasing PGC-1α expression. In a murine hindlimb ischemia model, the survival of transplanted melatonin-treated MSCs was significantly increased in the ischemic tissues, resulting in improvement of functional recovery, such as blood perfusion, limb salvage, neovascularization, and protection against necrosis and fibrosis. These findings indicate that the therapeutic effect of melatonin-treated MSCs in ischemic diseases is mediated via regulation of PGC-1α level. This study suggests that melatonin-induced PGC-1α might serve as a novel target for MSC-based therapy of ischemic diseases, and melatonin-treated MSCs could be used as an effective cell-based therapeutic option for patients with ischemic diseases.

• Food Science and Biotechnology
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• v.15 no.6
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• pp.866-870
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• 2006

The maintenance of physiological activity during dilution is very critical for the accurate enumeration of Vibrio spp. in marine samples. We investigated the effect of various diluents on the recovery of Vibrio parahaemolyticus using the direct plate counting and most probable number (MPN) methods. The effects of NaCl (0.85 and 3%) and pH (from 6.6 to 7.4) in diluents based on distilled water or phosphate buffered saline (PBS) were evaluated with three V. parahaemolyticus strains. PBS-3% NaCl (pH 6.6), as opposed to PBS, was the most effective diluent at maintaining viable cell numbers up to 2 log CFU/g during dilution for direct plate counting using on thiosulfate citrate bile salts sucrose (TCBS) selective agar, as well as minimizing the difference in cell numbers between TCBS and non-selective nutrient agar. It also increased counts of V parahaemolyticus inoculated into oysters relative to PBS (p<0.01), suggesting that PBS-3% NaCl (PH 6.6) can reduce the problem of underestimating V. parhaemolyticus counts using PBS alone.