• Mycobiology
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• v.47 no.3
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• pp.329-334
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• 2019

Streptomyces blastmyceticus strain 12-6 was isolated from a forest soil sample of Cheonan area on the basis of strong antifungal activities against plant pathogenic fungi. Butanol extracts of the cultural filtrates were active against C. acutatum, C. coccodes, C. gloeosporioides, F. oxysporum, and T. roseum. Active fractions were prepared by thin layer chromatography using silica gel plate; 12-6-2 ($R_f$ 0.36), 12-6-3 ($R_f$ 0.44). Scanning electron microscopy showed that the active fractions caused a change in surface texture of fungal spores from smooth surface to wrinkled surface. The lethal effect on the spores of the active fractions varied from 56% to 100%. It was shown that the spores of C. acutatum were more sensitive to the antifungal fractions than the spores of F. oxysporum. Fluorescence staining using TOTO-1 indicated that the antifungal fractions could make the spores more sensitive to the fluorescence dye. Thus, it was suggested that antifungal agents prepared in this study exhibited the antifungal activity by damaging the plasma membrane of both fungal spores and hyphae. Identification of antifungal agents in the active fraction using GC-MS analysis revealed the presence of cyclo-(Leu-Pro) and 9-octadecenamide as major components that have already been known as antifungal substances.

• KSBB Journal
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• v.16 no.4
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• pp.351-355
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• 2001

The information about organic and biomass fractions in sewage is essential for the optimal operation and model calibration of biological treatment processes. In the respect of that oxygen is directly associated with respiration and growth of biomass as well as substrate reduction, the respirometry is well known as a suitable method for the analysis of wastewater composition and active biomass. Thus, the organic and biomass fractions in sewage were measured using respirometry. The fraction of readily biodegradable substrate, slowly biodegradable substrate, inert soluble substrate and inert particular substrate are about 10-16%, 1-8%, 32-50% and 2-47%, respectively. The active heterotrophic biomass fraction is about 10-24%, but the autotrophic biomass was not detected in influent sewage.

• Korean Journal of Medicinal Crop Science
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• v.28 no.1
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• pp.29-37
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• 2020

Background: Although Gastrodia elata contains the valuable, bio-active compounds gastrodin and 4-hydroxybenzyl alcohol (4-HBA), it also contain ρ-cresol, which is a major source of an objectionable pig slurry-like odor. Accordingly, this study was performed to determine the deodorization effect of Diaion HP-20 resin on a G. elata extract. Methods and Results: Using Diaion HP-20 with an increasing concentration of ethanol, an extract of G. elata was fractionated into 15 fractions, which were anlayzed to determine their concentrations of active compounds and ρ-cresol. The gastrodin, 4-HBA, total phenolics, and ρ-cresol concentrations of the G. elata extract were 403.13, 408.15, 2,476.09, and 11.77 ㎍/㎖, respectively. Among the different fractions, gastrodin and 4-HBA were detected in fractions 3 to- 6, and 4 to- 10, respectively whereas total phenolics were detected in all samples, with fractions 5 to- 7 being characterized by higher concentrations than were the other fractions. ρ-Cresol was detected in fractions 12 to- 15, at concentrations ranging from 0.39 ㎍/㎖ to 6.05 ㎍/㎖ with the highest concentration detected in fraction 14. The fractions containing ρ-cresol could be selectively separated from the G. elata extract without the loss of major bio-active compounds such as gastrodin and 4-HBA. Conclusions: The results of this study indicate that a deodorizing method using Diaion HP-20 resin can be considered for improving the sensory qualities of G. elata extract without a loss of the major bio-active compounds.

• Korean Journal of Pharmacognosy
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• v.48 no.3
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• pp.208-212
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• 2017

In this study, analysis of active compounds that are believed to be highly relevant to antioxidant activity was carried out on the methanol extract and its solvent fractions of Corni fructus. The DPPH radical scavenging activity for the comparison of antioxidant activity was higher in order of aqueous fraction > methanol extract > ethyl acetate fraction > n-hexane fraction. It is similar to the order of total polyphenol contents in the samples. As a result of LC-MS analysis, phenolic acid compounds such as caffeic acid, gallic acid and chlorogenic acid and lognin, which is known as a representative active ingredient of Corni fructus, were identified as active compounds. And the antioxidative activity and the total polyphenol content of the extracts and solvent fractions were found to be related to the contents of the compounds. Particularly, it was confirmed that phenolic acid such as caffeic acid contributes to the antioxidative activity of the aqueous fraction of Corni fructus methanol extract.

• Fisheries and Aquatic Sciences
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• v.17 no.2
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• pp.181-187
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• 2014

This study was performed to identify the optimum fractionation method and conditions to obtain exopeptidase-active fractions from octopus hepatopancreas (HP) crude extracts (CEs) using four techniques: solid ammonium sulfate fractionation, polyethylene glycol (PEG) fractionation, anion exchange chromatography, and gel filtration chromatography. The fractions with the highest total activity toward L-leucine-p-nitroanilide (Leu-pNA) were fraction IV from the ammonium sulfate and PEG fractionation, and fraction II in ion exchange and gel filtration chromatography. The total exoprotease activity of these fractions was highest in fraction IV (4,050.20 U) of ammonium sulfate fractionation, followed by fraction II (3,600.28 U) from gel filtration chromatography, fraction IV (2,861.30 U) from PEG fractionation, and fraction II (2,576.28 U) from ion exchange chromatography. These results suggest that ammonium sulfate fractionation using 60-80% ammonium sulfate was the most efficient method for separating the exoprotease active fractions from CEs of octopus HP.

• Journal of the Korean Society of Food Science and Nutrition
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• v.38 no.2
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• pp.177-181
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• 2009

The peptides from Aroase AP10 enzymatic hydrolysates of octopus proteins were isolated and tested for inhibitory activity against angiotensin converting enzyme (ACE). The Aroase AP10 hydrolysates were filtered through PM-10 membrane (M.W. cut-off 10,000) to obtain the peptides fractions with ACE inhibition activity. These fractions were applied to a Biogel P-2 column. Three active fractions (A, B, and C) were collected and applied to a SuperQ-Toyopearl 650S column chromatography, leading to the isolation of four active fractions (A-1, A-2, B-1, and C-1). Among the active fractions, C-1 had the highest ACE inhibitory activity ($IC_{50}=3.10{\mu}g$). The main composition of its amino acids is arginine, lysine, histidine and leucine, which cover about 60% of the total amino acids.

• The Mathematical Education
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• v.40 no.2
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• pp.195-215
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• 2001

The purpose of this paper is to present a specific set of home teaching methods in hopes to prevent slow learner of the elementary mathematics. This paper deals with the number and operations, one of five topics in the elementary mathematics A survey of two hundred elementary school teachers was made to see the teacher's opinions of the role of home studying and to concretize the contents of the research topics. There were asked which is the most essential contents for the concrete loaming and which is the most difficult monad that might cause slow leaner. And those were found to be; counting, and arithmetic operations(addition and subtraction) of one or two-digit numbers and multiplication and their concepts representations and operations(addition and subtraction) of fractions. The home teaching methods are based on the situated learning about problem solving in real life situations and on the active teaming which induces children's participation in the process of teaching and learning. Those activities in teaching each contents are designed to deal with real objects and situations. Most teaching methods are presented in the order of school curriculum. To teach the concepts of numbers and the place value, useful activities using manipulative materials (Base ten blocks, Unifix, etc.) or real objects are also proposed. Natural number's operations such as addition, subtraction and multiplication are subdivided into small steps depending upon current curriculum, then for understanding of operational meaning and generalization, games and activities related to the calculation of changes are suggested. For fractions, this paper suggest 10 learning steps, say equivalent partition, fractional pattern, fractional size, relationship between the mixed fractions and the improper fraction, identifying fractions on the number line, 1 as a unit, discrete view point of fractions, comparison of fractional sizes, addition and subtraction, quantitative concepts. This research basically centers on the informal activities of kids under the real-life situation because such experiences are believed to be useful to prevent slow learner. All activities and learnings in this paper assume children's active participation and we believe that such active and informal learning would be more effective for learning transfer and generalization.

• Journal of Microbiology and Biotechnology
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• v.21 no.10
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• pp.1043-1048
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• 2011

A methanol extract of Cassia tora seeds was successively partitioned with diethyl ether, chloroform, ethyl acetate, and water, and the antitumor-promoting activity of the solvent fractions was determined by inhibition of Epstein-Barr virus early antigen (EBV-EA) activation induced by teleocidin B-4 in Raji cells. The diethyl ether (68.7%) and chloroform (91.2%) fractions and the hydrolysate (94.3%) of the ethyl acetate fraction had strong inhibitory activities. The chloroform and ethyl acetate fractions were chromatographed on silica gel and further purified by HPLC. Three active compounds, obtusifolin-2-glucoside (75.0%), chryso-obtusin-6-glucoside (56.8%), and norrubrofusarin-6-glucoside (39.4%), were obtained from the ethyl acetate fraction, and two active compounds, questin (97.9%) and chryso-obtusin (53.8%), were isolated from the chloroform fraction.

• Korean Journal of Pharmacognosy
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• v.31 no.3
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• pp.273-279
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• 2000

Leukotriene $B_4\;(LTB_4)$ is a pro-inflammatory mediator synthesized in myeloid cells from arachidonic acid. Elevated levels of $LTB_4$ have been found in a number of inflammatory diseases and levels are related to disease activity in some of these. Because $LTB_4$ interacts with cells through specific cell surface receptors, $LTB_4$ receptor blockade is the most specific approach to reduce the pathogenic role of $LTB_4$. In order to find $LTB_4$ receptor antagonist from plants, we screened the $LTB_4$ receptor antagonistic activity of the methanol extract and solvent fractions of herbal drugs. The ability of samples to inhibit specific binding of $[^3H]-LTB_4$ to human peripheral neutrophils was used as assay to evaluate the antagonistic activity of plant materials. Among the tested methanol extracts of herbal drugs, Mori Radicis Cortex, Perillae Semen, Armeniacae Semen and Sophorae subprostratae Radix showed potent inhibitory activity above 70% at the concentration of $100\;{mu}g/ml$. The inhibitory activities of $LTB_4$ binding to human neutrophils were evaluated for several solvent fractions at three different concentrations. Especially, hexane soluble fractions of Anemarrhenae Rhizoma and Embeliae Radix, and ethyl acetate soluble fractions of Aristolochiae Fructus, Magnoliae Cortex and Zingiberis Rhizoma crudus showed moderate activity at $25\;{mu}g/ml$. These fractions were promising candidates for the study of the activity-guided chromatographic purification of active compounds. Silica gel column chromatography of hexane soluble fractions of Anemarrhenae Rhizoma and Embeliae Radix gave very active sub-fractions, AA-4 and ES-4, and their inhibition activities of $LTB_4$ binding to human neutrophil at $30\;{mu}g/ml$ were 78% and 62%, respectively. From these results we could anticipate new $LTB_4$ receptor antagonist from herbal drugs, and the block of $LTB_4$ effects may provide beneficial in neutrophil mediated diseases such as inflammation and bronchial asthma.

• Journal of Microbiology and Biotechnology
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• v.10 no.2
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• pp.227-232
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• 2000

Fresh pine needles were collected and extracted with 95% methanol and the extract was concentrated to determine its antimicrobial activity. The methanol extract had a considerable inhibitory effect on the tested bacteria, such as Esherichia coli 0157;H7, Listeria monocytogenes, Salmonella typhimurium, and Staphylococcus aureus. The methanol extract of pine needles was further fractionated to chloroform, ethylacetate, butanal, and water fractions. Among these four fractions, the butanol and water fractions, which showed a relatively strong inhibitory effect on all of the tested bacteria, were purified and the minimum ingibitory concentration (MIC) was determined for each microorganism. The MIC raged between 25 mg/ml and 45 mg/ml depending on the microorganism. the purified active fractions were applied to sterilized milk as a model food system to define the antimicrobial effectiveness and it was found that the antimicrobial activities in the water fractions were stronger than those in the butanol fractions.