• Korean Journal of Soil Science and Fertilizer
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• v.7 no.1
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• pp.29-34
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• 1974

On a newly reclamed acidic Song-jong soil (soil of a member of fine loamy, mesic family of Hapludults) an experiment was carried out to find out the proper measure of the improvement of soil fertility with soybean as test crop. Results are summarized as follow: 1. Application of compost (1 ton/10a), lime (lime requirement)and fused phosphate (equivalent to 5% of the phosphate fixation coefficient)resulted in the increase of soybean yield by 93.3% over the check plot (N: 6kg/10a, $P_2O_5$: 9kg/10a, $K_2O$: 6kg/10a). The application of fused phosphate at the level of 5% of phosphate fixation coefficient N (6kg/10a) and K(6kg/10a) brought the yield increase by 62.7% over the check plot. However, although the pH of the soil was adjusted to 7.0 by liming, the application of lime with moderate dose of phosphate ($P_2O_5$: 9kg/10a) did not increase the yield of soybean significantly. And the application of fused phosphate at the level of 5% of phosphate fixation coefficient increased the available soil P from 14 ppm to around 100 ppm as tested after harvest. 2. Application of compost (1 ton/10a) increased the organic matter content of soil by 0.8% when tested after harvest. While, the application of rice straw (0.5 ton/10a) did not alter the soil organic matter content. The CEC of the soil tested after havest found incereased significantly by the addition of lime and compost. 3. Plant analysis revealed that the $K_2O/Ca+Mg$ is better correlated with the yield than the absolute concentration of $K_2O$ in plant tissue. Between the concentration of $P_2O_5$ in plant tissue and the yield of soybean, a typical C-curve relationship was observed, indicating that in this particular soil, phosphate was the primary growth liming factor.

• Korean Journal of Oriental Medicine
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• v.3 no.1
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• pp.67-83
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• 1997

In order to search for anti-influenza virus type A agents from Korean medicinal herbs, we selected 100 medicinal herbs, based on a review of the Korean traditional medicine books. Four of 100 Korean medicinal herbs, MM-40, MM-55, MM-63, MM-110, exhibited very strong anti-influenza virus activity. The fractions of four medicinal herbs, which had very strong anti-influenza virus activity, were tested for antiviral activity by means of Haemagglutination inhibition test(HTT), 40% MeOH fraction of MM-40, $H_2O$ fraction of MM-55, 20% fraction of MM-63 3nd $H_2O$ fraction of MM-110 had strong anti-influenza virus activity at the range of $78{\mu}g/ml$ to $156{\mu}g/ml$, 1.56mg/ml to 100mg/ml, 6.25mg/ml to 50mg/ml and $48.7{\mu}g/ml$ to $780{\mu}g/ml$, respectively. These results of HIT indicated that fractions of Korean medicinal herbs might inhibit either attachment of virus to cell surface receptor or penetration of virus into cell during the initial stage of infection. In the cytotoxicity of fractions against red blood cells, 40% MeOH fraction of MM-40, 20% fraction of MM-63 and $H_2O$ fraction of MM-110 showed cytotoxicity at the range of $78{\mu}g/ml$ to 10mg/ml, 50mg/ml to 100mg/ml and $195{\mu}g/ml$ to 100mg/ml, respectively, whereas $H_2O$ fraction of MM-55 did not show cytotoxicity. In order to establish influenza virus adapted animal model, influenza virus type A were passaged 3 and 4 times successively in Balb/c mouse. As a result, we had 4 HA unit titers on the 5 days of 3rd passages and 7 days of 4th passages after infection, respectively.

• Archives of Pharmacal Research
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• v.27 no.2
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• pp.164-168
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• 2004

The chromatographic separation of the MeOH extract of the aerial parts of Solidago virga-aurea var. gigantea $M_{IQ}$ . (Compositae) led to the isolation of six terpenoids and four phenolic compounds, trans-phytol (1), ent-germacra-4(15),5,10(14 )-trien-1$\alpha$-ol (2), $\beta$-amyrin acetate (3), ent-germacra-4(15),5,10(14)-trien-1$\beta$-ol (4), $\beta$-dictyopterol (5), oleanolic acid (6), kaempferol (7), kaempferol-3-O-rutinoside (8), methyl 3,5-di-O-caffeoyl quinate (9), and 3,5-di-O-caffeoyl quinic acid (10). Their structures were established by chemical and spectroscopic methods. Compounds 4, 5, and 10 showed moderate cytotoxicity against five cultured human tumor cell lines in vitro with its E $D_{50}$ values ranging from 1.52∼18.57 $\mu\textrm{g}$/mL.L.

• Korean Journal of Soil Science and Fertilizer
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• v.18 no.3
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• pp.297-303
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• 1985

Three field experiments were conducted to define the optimum levels, yield responses and fertilization efficiencies of NPK fertilizers on peanut and survey on fertility status of 150 farmers` peanut fields was carried out for 3 years. The range of optimum rates of N, $P_2O_5$ and $K_2O$ fertilizers on peanut were 5.2-9.0, 6.4-21.0, 8.5-15.0kg/10a, respectively. The effect of NPK application were 23, 8, 16% and production efficiencies of each kg of NPK fertilizers were 6.0, 1.8, 3.4 kg, respectively. The optimum nutrient contents in soil were 250 ppm for available $P_2O_5$ and 0.8 me/100g for exchangeable K including applied ones. Available soil nutrient contents of farmers' peanut fields were mostly below the optimum range for upland soil.

• Journal of the Korean Wood Science and Technology
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• v.43 no.5
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• pp.591-599
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• 2015

Cercidiphyllum japonicum leaves were collected, air-dried and extracted with 70% aqueous acetone, then concentrated and sequentially fractionated using n-hexane, methylene chloride ($CH_2Cl_2$), ethylacetate (EtOAc), and $H_2O$. A portion of EtOAc fraction (10 g) was chromatographed on a Sephadex LH-20 column, by the successively elution with various aqueous $MeOH-H_2O$ (1:9, fraction $1-2{\rightarrow}3:7$, fraction $3-5{\rightarrow}1:1$, fraction $6-9{\rightarrow}7:3$, fraction $10-13{\rightarrow}9:1$, fraction 14-16). Compound 2 was isolated from fraction 6 and compound 1 was separated from fraction 11 and 12. Compound 3 and 4 were purified from fraction 13. The isolated compounds were elucidated as quercetin-3-O-${\alpha}$-L-rhamnopyranoside (1), chlorogenic acid (2), quercetin-3-O-${\alpha}$-L-arabinofuranoside (3) and quercetin-3-O-${\beta}$-D-xylopyranoside (4) by the spectral and literature data, and by comparison with the authentic samples. These compounds were reported, for the first time, from the extracts of C. japonicum leaves. Also chlorogenic acid (2) has never been reported before in domestic tree species and can be used as an index compound for C. japonicum.

• Korean Journal of Food Science and Technology
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• v.44 no.3
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• pp.362-366
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• 2012

This study was performed to promote the effective utilization of edible marine resources and to develop functional food material from edible marine resource extracts for inhibiting lipid accumulation in liver. Edible marine resource extracts (ME) were prepared by hot water (MWE) and 80% ethanolic (MEE), and both the MWE and MEE extracts were assessed as to their cell cytotoxicity, and Oil Red O staining. Results demonstrated that ME showed no cytotoxic effects. However, treatment with MEE in the concentration of 1000, 500, and 250 ${\mu}g/mL$ significantly inhibited the lipid accumulation in HepG2 cells compared to MWE. Especially, among the 80% ethanolic extracts, Pagrus major, Larimichthys polyactis, Clupea pallasii, Octopus minor, Enteroctopus dofleini, Styela clava, dried sea mustard, and Enteromorpha intestinalis showed greater lipid accumulation inhibitory activity than the others.

• Food Science and Biotechnology
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• v.18 no.1
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• pp.95-102
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• 2009

The aerial parts of garland (Chrysanthemum coronarium L.) were extracted in 80% aqueous methanol (MeOH) and the concentrated extract was then partitioned using ethyl acetate (EtOAc), n-butanol (n-BuOH), and $H_2O$, successively. EtOAc and n-BuOH fractions resulted in 4 glycerides with the application of octadecyl silica gel and silica gel column chromatography. The chemical structures of the glycerides were determined using several spectroscopic methods, including nuclear magnetic resonance (NMR) and mass spectrometry (MS) as (2S)-1-O-palmitoyl-sn-glycerol (1), (2S)-1-O-oleoyl-2-O-oleoyl- 3-O-$\beta$-D-galactopyranosyl-sn-glycerol (2), (2S)-1-O-palmitoyl-2-O-linoleoyl-3-O-phosphorouscholine-sn-glycerol (3), and (2S)-1-O-linolenoyl-2-O-palmitoyl-3-O-[$\alpha$-D-galactopyrasyl-($1{\rightarrow}6$)-$\beta$-D-galactopyranosyl]-sn-glycerol (4). The free fatty acids of these glycerides were determined with gas chromatography (GC)-MS analysis following alkaline hydrolysis and methylation. These glycerides demonstrated an inhibitory effect on acyl-CoA: cholesterol acyltransferase (ACAT, compound 1: $45.6{\pm}0.2%$ at $100{\mu}g/mL$), diacylglycerol acyltransferase (DGAT, compound 1: $59.1{\pm}0.1%$ at $25{\mu}g/mL$), farnesyl protein transferase (FPTase, compound 2: $98.0{\pm}0.1%$; compound 3: $55.2{\pm}0.1%$ at $100{\mu}g/mL$), and $\beta$-secretase ($IC_{50}$, compound 4: $2.6{\mu}g/mL$) activity. This paper is the first report on the isolation of these glycerides from garland and their inhibitory activity on ACAT, DGAT, FPTase, and $\beta$-secretase.

• Journal of the Korean Wood Science and Technology
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• v.41 no.6
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• pp.566-575
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• 2013

The fruits of Taxus cuspidata were collected, divided into seeds and fruits, and extracted with 95% EtOH. The extracts were evaporated under the reduced vacuum pressure, concentrated, then successively fractionated with a series of n-hexane, dichloromethane, ethyl acetate and water on a separatory funnel to get some freeze dried samples. A portion of the EtOAc (arils:1.65 g, seeds:1.04 g) and $H_2O$ (arils:7 g, seeds:10 g) soluble samples were chromatographed on a Sephadex column using MeOH-$H_2O$ (1:1, 1:3, 1:5, v/v), EtOH-hexane (3:1, v/v) mixture and 100% $H_2O$ as eluting solvents to isolate pure compounds from the fractions. The isolates were developed by cellulose TLC using t-BuOH-HOAc-$H_2O$ (TBA; 3:1:1, v/v/v) and 6% aqueous HOAc. Visualization was done under ultraviolet light and by spraying the vanillin-HCl-EtOH reagent (4.8:12:480, v/v/v). followed by heating. The structures of the isolates were characterized by $^1H$- and $^{13}C$-NMR, DEPT, 2D-NMR, LC/MS and EI-MS spectra. In addition to the NMR and MS spectra, acid hydrolysis and permethylation were used to determine the correct structure of the isolated sugar compound. Their structures were elucidated as (+)-catechin (1), (-)-epicatechin (2), (+)-gallocatechin (3), (-)-epigallocatechin (4) and ${\beta}$-D-fructofuranose-($2{\rightarrow}4$)-O-${\beta}$-D-glucopyranose($1{\rightarrow}4$)-O-${\alpha}$-D-glucopyranose ($1{\rightarrow}2$)-O-${\beta}$-D-fructofuranose (5) on the basis of the above experimental evidences.

• Journal of the Korea Society of Computer and Information
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• v.18 no.11
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• pp.159-165
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• 2013

This paper proposes a O(E) polynomial-time algorithm that has been devised to simultaneously solve edge-coloring problem and graph classification problem both of which remain NP-complete. The proposed algorithm selects an edge connecting maximum and minimum degree vertices so as to determine the number of edge coloring ${\chi}^{\prime}(G)$. Determined ${\chi}^{\prime}(G)$ is in turn either ${\Delta}(G)$ or ${\Delta}(G)+1$. Eventually, the result could be classified as class 1 if ${\chi}^{\prime}(G)={\Delta}(G)$ and as category 2 if ${\chi}^{\prime}(G)={\Delta}(G)+1$. This paper also proves Vizing's planar graph conjecture, which states that 'all simple, planar graphs with maximum degree six or seven are of class one, closing the remaining possible case', which has known to be NP-complete.

• Natural Product Sciences
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• v.11 no.3
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• pp.119-122
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• 2005

In the course of searching for hepatoprotective agents from natural products, four compounds were isolated from the MeOH extract of Sanguisorbae Radix, as guided by their DPPH free radical scavenging activity. The structures were determined as 4,5-dimethoxy-3-hydroxybenzoic acid methyl ester (1), (+)-gallocatechin (2), methyl $6-O-galloyl-{\beta}-D-glucopyranoside$ (3), and pomolic acid $3-O-[{\alpha}-L-arabinopyranoside]-28-O-[{\beta}-D-glucopyranosyl]$ ester (ziyu-glycoside I) (4). Compounds 2 and 3 showed significant DPPH free radical scavenging effects, exhibiting $IC_{50}$ values of 11.4 and $13.0\;{\mu}M$, respectively. L-Ascorbic acid was used as a positive control and exhibited the $IC_{50}$ value of $50.3\;{\mu}M$. In evaluation of the hepatoprotective activity of the isolated compounds on drug-induced cytotoxicity, compound 2 showed the significant hepatoprotective effect with the $EC_{50}$ value of $91.84\;{\pm}\;11.0\;{\mu}M$ on tacrine-induced cytotoxicity in Hep G2 cells, while silybin, a positive control, exhibited $EC_{50}$ value of $122.4\;{\pm}\;12.5\;{\mu}M$.