• Economic and Environmental Geology
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• v.24 no.3
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• pp.319-327
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• 1991

Cheju is the biggest island in Korean peninsula, consisted entirely of volcanic rocks and pyroclastic sediments. The topography is characterized by wide basalt plain in the low altitude but at the center of island, basalt volcano rises 1,950m above sea-level. Surface drainage is very poor, therefore water supply has been dependent on ground water and natural springs. There are about 1,650 production wells and most of them yield $1,000{\sim}2,000mm^3/day$. According to increase of ground water use, saline water is intruded in the low altitude of coastal area. Specially in the eastern coastal area, the topography is extensively flat and the level of ground water is very close to sea-level, at which overuse of ground water has brought saline intrusion up to maximum 6km far from the coast. Hydrochemical monitoring on this salt water intrusion is now undertaken on long term base.

• Korean Journal of Environmental Agriculture
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• v.30 no.3
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• pp.243-251
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• 2011

BACKGROUND: Gypsum($CaSO_4{\cdot}2H_2O$) is known as an ideal amendment to improve soil quality of the reclaimed coastal land. Since gypsum has very high concentration of electron acceptor like ${SO_4}^{2-}$, its application might be effective on reducing $CH_4$ emission during rice cultivation, but its effect has not been studied well. METHODS AND RESULTS: The effect of gypsum on $CH_4$ emission and rice growth characteristics was studied by pot test, which was packed by reclaimed paddy soils collected from Galsa, Hadong, Gyeongnam province. Chemical-grade gypsum was applied in two soils having EC 2.25 and 9.48 dS/m at rates of 0, 0.5, 1.0 and 2.0%(wt/wt). $CH_4$ emission was characterized a week interval by closed chamber method during rice cultivation. $CH_4$ emission rate was significantly decreased with increasing salt accumulation and gypsum application levels. With increasing gypsum application, dissolved ${SO_4}^{2-}$ concentration in the leachate water was significantly increased, which might have suppressed $CH_4$ production in soil. Total $CH_4$ flux was dramatically decreased with increasing gypsum application. In contrast, rice yield was increased with increasing gypsum application and then achieved maximum productivity at 1.0% gypsum application in two soils. CONCLUSION(s): Gypsum is a very good soil amendment to suppress $CH_4$ emission in reclaimed coastal paddy soils, and improve rice productivity and soil properties. The optimum application level of gypsum is assumed at ca. 1% to improve soil productivity with reducing effectively $CH_4$ emission during rice cultivation.

• Journal of Applied Biological Chemistry
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• v.55 no.2
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• pp.129-133
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• 2012

To exploit plant growth promoting bacteria in the roots of Miscanthus sacchariflorus, a biomass energy crop, total 64 bacteria were isolated. For the investigation of plant growth promoting effects from the isolated bacteria, production of indole acetic acid (IAA) and 1-aminocyclopropane-1-carboxylic acid (ACC) deaminase activities were tested and other cultural conditions were examined. As results, 8 isolates showed plant growth promoting effects on the M. sacchariflorus and an isolate designated Agrobacterium sp. BE516 has the highest activity by enhancing the shoot elongation over 2-fold than the control. Agrobacterium sp. BE516 produced 64 ${\mu}g$ IAA per mL and showed ACC deaminase activity which is involved in the resistance to environmental stress such as high salt and drought. It could grow at low temperature in the range from 4 to $15^{\circ}C$, at pH 4.0 and at 4% NaCl. These results indicate that the Agrobacterium sp. BE516 can be useful as a bio-fertilizer for M. sacchariflorus under the stressed conditions.

• Korean Journal of Agricultural and Forest Meteorology
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• v.14 no.2
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• pp.71-78
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• 2012

Eupatilin, one of representative medical components of mugwort, can be efficiently extracted from the 'Gangwha Sajabalssuk'. The Eupatilin content may depend on environmental factors such as soil and regional climate in addition to a genetic factor and Gangwha region has a profitable environmental condition for the mugwort growth. In this study, the climatological characteristics of Gangwha was analyzed in order to find the environmental condition of mugwort containing high Eupatilin in term of atmospheric, oceanographic and land variables. The climate of Gangwha is characterized by the relatively low daily temperature and large diurnal variation with plenty of solar radiation, long sunshine duration and less cloudiness. According to our correlation analysis, the long sunshine duration and the large diurnal temperature variation are highly correlated with the Eupatilin contents. The result implies that Gangwha has the favorable conditions for the cultivation and the habitat of the high-Eupatilin concentrated mugwort. Because of the sea surrounding Gangwha Island with low salinity and moderate wind, the salt contained in sea breeze is relatively low compared to other regions. Furthermore, Gangwha has clean atmospheric environment compared to other regions because the concentrations of toxic gases harmful to crop growth such as nitrogen dioxide ($NO_2$), sulfite gas ($SO_2$) and fine dust (PM-10) are lower in the air. The ozone ($O_3$) concentration is moderate and within the level of natural production. It is also found that moderately coarse texture or fine loamy soils known as good for water drainage and for the growth and cultivation of the 'Gangwha-mugwort' are distributed throughout the areas around mountainous districts in Gangwha, coinciding with those of mugwort habitat.

• Food Engineering Progress
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• v.14 no.1
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• pp.65-74
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• 2010

Culture conditions of L. plantarum TJ-LP-002, the garlic resistant strain isolated from pakimchi (green onion kimchi), were investigated for the use of feed additives. Acetic acid, citric acid, lactic acid, and tartaric acid were detected in the culture supernatant, and especially the concentrations of lactic acid and acetic acid significantly increased during cultivation. The antimicrobial activity of L. plantarum TJ-LP-002 was not affected by proteases, calatase or cellulase, which showed that the antimicrobial activity might be due to the production of acids rather than proteinaceous antimicrobial substances. L. plantarum TJ-LP-002 was resistant to neomycin sulfate, spectinomycin dihydrochloride, and lincomycin hydrochloride, sensitive to streptomycin sulfate, and intermediate resistant to ampicillin trihydrate, chloramphenicol, erythromycin, tetracycline hydrochloride, and kanamycin sulfate. The optimum initial pH of medium, fermentation temperature and time for the cell growth and antibacterial activity were pH 7.0, 30${^{\circ}C}$ and 24hr, respectively. The optimal composition of culture medium for the cell growth and antimicrobial activity was 3%(w/v) glucose as a carbon source, 3%(w/v) yeast extract as a nitrogen source, and manganese sulfate and ammonium citrate as inorganic salts. The combinatorial supplementation of these inorganic salts, rather than sole addition as an inorganic salt, resulted in better antibacterial activity.

• Food Science and Preservation
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• v.24 no.3
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• pp.413-420
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• 2017

This study was designed to examine the in vitro antioxidant and anti-inflammatory effects of red beet (Beta vulagaris) root. Red beet root was extracted using 70% ethanol and then fractionated sequentially with n-hexane, ethyl acetate and butanol. Antioxidative ability was evaluated by bioassays using total polyphenol contents and ABTS (2,2'-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid diammonium salt) radical scavenging activity. Ethyl acetate fraction of red beet root was best on total polyphenol contents ($37.02{\pm}0.37mg\;GAE/g$) and ABTS radical scavenging effects ($IC_{50}$ $42.9{\pm}9.5{\mu}g/mL$). For the anti-inflammatory activity in RAW264.7 cells, the hexane fraction showed the highest inflammatory effect. Dose response studies were performed to determine the inhibitory effect of hexane fraction of red beet root on pro-inflammatory mediators in lipopolysaccharide (LPS)-stimulated RAW264.7 cells. The hexane fraction of red beet root inhibited the NO and $PGE_2$ production and the protein level of iNOS and COX-2, and protein expression of pro-inflammatory cytokines ($TNF-{\alpha}$, IL-6 and $IL-1{\beta}$), in a dose-dependent manner. These results suggest that red beet root has considerable potential as a functional food ingredient with antioxidative and anti-inflammatory effects.

• Food Science and Preservation
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• v.25 no.1
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• pp.27-35
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• 2018

In this study, we evaluated the antioxidant activity and anti-inflammatory effects of Abeliophyllum distichum (A. distichum) leaves that were prepared via air-drying. Fresh and air-dried A. distichum leaves were examined via 1,1-diphenyl-2-picryl hydrazyl (DPPH) radical, and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) radical scavenging assay and measurements of the reducing power. The suppression effects on inflammation of the leaves were analyzed by a western blot and RT-PCR on LPS-induced RAW 264.7 cells. As a result, the antioxidant activity of the fresh leaves was found to be more effective than that of the air-dried leaves. Also, the fresh leaves were more effective in suppressing the protein and mRNA levels of iNOS and COX-2 than the air-dried leaves, thereby indicating the better anti-inflammatory effects. In addition, the contents of phenolic compounds and acteoside were analyzed by high-performance liquid chromatography (HPLC). The results showed that the acteoside content decreased with the use of the air-drying method, while there was no change in the content of phenolic compounds. Therefore, this study indicated that fresh A. distichum leaves potential antioxidant and suppression activities of various factors that are involved in the production of NO, which were found to be better than those of air-dried A. distichum leaves. These biological activities were also found to be independent of the content of phonolic compounds and were assumed to be directly or indirectly related to the content of acteoside.

• Journal of Applied Biological Chemistry
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• v.64 no.4
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• pp.333-341
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• 2021

In this study, to select strains suitable as microbial agent from among rhizosphere microorganisms present in rhizosphere soil and roots, the mineral solubilization ability, antifungal activity against 10 types of plant pathogenic fungi, and plant growth-promoting activity of rhizosphere microorganisms were evaluated. As a result, DDP346 was selected because it has solubilization ability of phosphoric acid, calcium carbonate, silicon, and zinc; nitrogen fixing ability; production ability of siderophore, indole-3-acetic acid, and aminocyclopropane-1-carboxylate deaminase; and antifungal activity against seven types of plant pathogenic fungi. DDP346 showed a 99.9% homology with Acinetobacter pittii DSM 21653 (NR_117621.1); phylogenetic analysis also revealed a close relationship with Acinetobacter pittii based on the 16S rRNA base sequence. The growth conditions of DDP346 were identified as temperatures in the range of 10-40 ℃, pH in the range of 5-11, and salt concentrations in the range of 0-5%. In addition, a negative correlation coefficient (r² = -0.913, p <0.01) was shown between pH change and the solubilized phosphoric acid content of Acinetobacter sp. DDP346, and this is assumed to be due to the organic acid generated during culture. Consequently, through the evaluation of its mineral solubilization ability, antifungal activity against plant pathogenic fungi, and plant growth-promoting activity, the potential for the utilization of Acinetobacter sp. DDP346 as a multi-purpose microbial agent is presented.

• The Korea Journal of Herbology
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• v.36 no.3
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• pp.15-24
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• 2021

Objectives : The Glycyrrhiza new varieties, WONGAM and SINWONGAM, were developed through interspecific cross between Glycyrrhiza glabra and Glycyrrhiza uralensis by the National Institute of Horticultural and Herbal Science, Rural Development Administration in Korea. This in vitro study was undertaken to compare the antioxidant and cytotoxic effects between Glycyrrhiza new varieties (WONGAM and SINWONGAM) and official compendia (Glycyrrhiza glabra and Glycyrrhiza uralensis). Methods : Antioxidant activity was determined by DPPH (1,1-diphenyl-2-picrylhy drazyl), ABTS (2,2-azino-bis (3-rthylbenz-thiazoline-6-sulfonic acid)) diammonium salt, Nitrite radical scavenging assay, and Reducing Power assay. Cytotoxicity was determined by MTT assay and cell morphology was observed by an inverted microscope. Results : The DPPH, ABTS, Nitrite radical scavenging activities and reducing power of Glycyrrhiza glabra, Glycyrrhiza uralensis, WONGAM, and SINWONGAM were evaluated at different concentrations (0, 10, 50, 100, 500, 1000 ㎍/㎖). Glycyrrhiza glabra, Glycyrrhiza uralensis, WONGAM, and SINWONGAM showed similar dose-dependent increase in antioxidant activities. The cytotoxic effects with increasing doses of Glycyrrhiza new varieties and official compendia did not differ in HCT116, HT29, A549, MDA-MB231, PC3, ACHN, and HeLa cells. However, significant difference in cytotoxicity were observed in AGS, MCF7 and Hep3B cells by Glycyrrhiza glabra, Glycyrrhiza uralensis, WONGAM, and SINWONGAM. Conclusions : These results showed that Glycyrrhiza new varieties and official compendia acts as a potent antioxidant. Also, the finding that equivalent cytotoxic potency was observed in a cell dependent manner. Our study suggests that Glycyrrhiza new varieties may offer a wide-variety of health benefits.

• Resources Recycling
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• v.30 no.1
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• pp.44-52
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• 2021

This study investigated the effect of the type of alkaline precipitant used on the synthesis of lithium hydroxide by examining the behavior of lithium hydroxide produced using lithium sulfate recovered from a waste lithium secondary battery as a raw material. The double-replacement reaction (DRR) process was used to remove the impurities contained in the lithium salt precursor of lithium sulfate and to improve the efficiency of the synthesis of lithium hydroxide. The experiment was conducted by control the molar ratio of the precursor ([Li]/[OH]), the reaction temperature, and the composition of the alkaline precipitant (KOH, Ca(OH)2, Ba(OH)2) used for the production of highly-crystalline lithium hydroxide. A secondary solid-liquid separation was performed following the reaction to remove the impurities generated, and the purified aqueous solution of lithium hydroxide was evaporated to remove the moisture and obtain the product as a powder. The crystallinity and synthesis behavior of the product were examined.