• Proceedings of the Korean Society of Crop Science Conference
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• 2007.04a
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• pp.65-73
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• 2007

The objective of this study is to understand how regulatory mechanisms respond to sugar status for more efficient carbon utilization and source-sink regulation in plants. So, we need to identify and characterize many components of sugar-response pathways for a better understanding of sugar responses. For this end, genes responding change of sugar status were screened using Arabidpsis cDNA arrays, and confirmed thirty-six genes to be regulated by sucrose supply in detached leaves by RNA blot analysis. Eleven of them encoding proteins for amino acid metabolism and carbohydrate metabolism were repressed by sugars. The remaining genes induced by sugar supply were for protein synthesis including ribosomal proteins and elongation factors. Among them, I focused on three hydrolase genes encoding putative $\beta$-galactosidase, $\beta$-xylosidase, and $\beta$-glucosidase that were transcriptionally induced in sugar starvation. Homology search indicated that these enzymes were involved in hydrolysis of cell wall polysaccharides. In addition to my results, recent transcriptome analysis suggested multiple genes for cell wall degradation were induced by sugar starvation. Thus, I hypothesized that enzyme for cell wall degradation were synthesized and secreted to hydrolyze cell wall polysaccharides producing carbon source under sugar-starved conditions. In fact, the enzymatic activities of these three enzymes increased in culture medium of Arabidopsis suspension cells under sugar starvation. The $\beta$-galactosidase encoded by At5g56870 was identified as a secretory protein in culture medium of suspension cells by mass spectrometry analysis. This protein was specifically detected under sugar-starved condition with a specific antibody. Induction of these genes was repressed in suspension cells grown with galactose, xylose and glucose as well as with sucrose. In planta, expression of the genes and protein accumulation were detected when photosynthesis was inhibited. Glycosyl hydrolase activity against galactan also increased during sugar starvation. Further, contents of cell wall polysaccharides especially pectin and hemicellulose were markedly decreased associating with sugar starvation in detached leaves. The amount of monosaccharide in pectin and hemicellulose in detached leaves decreased in response to sugar starvation. These results supported my idea that cell wall has one of function to supply carbon source in addition to determination of cell shape and physical support of plant bodies.

• KSBB Journal
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• v.6 no.4
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• pp.369-377
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• 1991

The effects of nitrogen sources(sodium glutamate and peptone) on the production of xanthan gum were investigated. The fermentation using sodium glutamate as a nitrogen source is longer than that of peptone. In the initial nitrogen concentration of 0.4-1.0g/L, Bs was about 2.0 and ${\beta}$s was 1.2. The optimal yields were obtained when the carbon source/nitrogen concentration was 10-16. The fermentation time and product yields in the fermentation medium of mixed nitrogen source [sodium glutamate-N(0.75g/L)+peptone-N(0.25g/L)] were similar to those of peptone.

• ETRI Journal
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• v.43 no.3
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• pp.571-571
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• 2021

• Korean Journal of Microbiology
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• v.40 no.1
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• pp.54-59
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• 2004

$\beta$-Glucan has been efficiently produced with higher yield by the optimization of liquid cultivation conditions. The optimal composition of medium for batch culture was 5% (w/v) of glucose as a carbon source, 0.5% (w/v) of yeast and 0.5% (w/v) of malt extract as a nitrogen source, 0.1% (w/v) of $KH_2PO_4$ and 0.05% (w/v) $MgSO_4{\cdot}7H_2O$, which had been the base medium for determination of other conditions. The set-up conditions are pH 5.0, $28^{\circ}C$, 1 vvm for aeration and 300 rpm for agitation. In order to minimize the inhibition effect of glucose on the initial growth of mycelia and to maximize the production of extracellular $\beta$-glucan, we have reduced the initial glucose feed to 4% and added 2nd feed at the point of 70 hr from the initial feed. The 2nd feed was composed of glucose 3%, yeast extract 0.1 % and malt extract 0.1 %. It improved the $\beta$-glucan yield upto 5.2 g/L in comparison with 2.8 g/L resulted from batch cultivation. Moreover, the serial treatment of a cell wall lytic enzyme and bromelain to the mycelia was effective for extraction of the cell wall bound $\beta$-glucan. The yield of $\beta$-glucan extraction by the enzyme treatment was 3.5 g/L, which was almost 4 times higher than that by hot-water extraction.

• Journal of the Korean Wood Science and Technology
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• v.38 no.5
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• pp.429-438
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• 2010

In this study, effect of carbon source on the hydrolytic ability of the enzyme from Fomitopsis pinicola, a brown rot fungi, for lignocellulosic biomass were examined on two lignocellulosic biomasses (rice straw and wood) without any pretreatment. Cellulase activities of crude enzyme from F. pinicola, which was cultured on softwood mixture as a carbon source, were 19.10 U/$m{\ell}$ for endo-${\beta}$-1,4-gulcanase (EG), 36.1 U/$m{\ell}$ for ${\beta}$-glucosidase (BGL), 7.27 U/$m{\ell}$ for cellobiohydrolase (CBH), and 7.12 U/$m{\ell}$ for ${\beta}$-1,4 xylosidase (BXL). Softwood mixture as a carbon source in F. pinicola comparatively enhanced cellulase activities than rice straw. The optimal pH and temperature of the cellulase was identified to pH 5 and $50^{\circ}C$for the hydrolysis of rice straw. Under these condition rice straw was hydrolyzed to glucose by the cellulase up to $32.0{\pm}3.1%$ based on the glucan amount of the rice straw for 72 h, while the hydrolytic capability of commercial enzyme (Celluclast 1.5${\ell}$) from rice straw to glucose was estimated to $53.7{\pm}4.7%$ at the same experimental condition. In case of addition of Tween 20 (0.1% w/w, substrate) to the cellulase the hydrolysis of rice straw to glucose was enhanced to $38.1{\pm}2.0%$.

• Natural Product Sciences
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• v.24 no.2
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• pp.132-138
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• 2018

Phytochemical investigation of 80% MeOH extract of the aerial parts of Capsella bursa-pastoris yielded fourteen compounds (1 - 14). The structures of the compounds were elucidated by spectroscopic methods to be methyl-1-thio-${\beta}$-D-glucopyranosyl disulfide (1), 10-methylsulphinyl-decanenitrile (2), 11-methyl-sulphinyl-undecanenitrile (3), 1-O-(lauroyl)glycerol (4), phytene-1, 2-diol (5), (3S,5R,6S,7E)-5,6-epoxy-3-hydroxy-7-megastigmen-9-one (6), loliolide (7), ${\beta}$-sitosterol (8), 3-hydroxy-1-(4-hydroxy-3-methoxyphenyl)-1-propanone (9), 1-feruloyl-${\beta}$-D-glucopyranoside (10), pinoresinol-4'-O-${\beta}$-D-glucopyranoside (11), luteolin (12), quercetin-3-O-${\beta}$-D-glucopyranoside (13), and luteolin 6-C-${\beta}$-glucopyranoside (14). Although compound 1 was reported as synthetic compound, 1 was first isolated from natural source. NMR spectral data assignments of 1, 2 and 3 were reported for the first time, and compounds 1 - 14 were for the first time reported from this plant source. The anti-inflammatory effects of 1 - 14 were evaluated in lipopolysaccharide (LPS)-stimulated murine microglia BV-2 cells. Compounds 12 exhibited strong inhibitory effects on nitric oxide production in LPS-activated BV-2 cells with $IC_{50}$ values of $9.70{\mu}M$.

• Journal of the Korean Applied Science and Technology
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• v.9 no.2
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• pp.157-163
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• 1992

A microorganism, isolated from soil and designated Pseudomonas sp13, produced two kinds of rhamnolipid in the medium containing glucose as carbon source. There were both rhamnolipid contain L-rhamnose and ${\beta}$-hydroxydecanoic acid. Coumpound A and B elucted chloroform-methanol mixed solution of silicic acid column chromatography and recrystallized from a mixture of ether and n-hexane. Studies on the structure of these products reveled that compound A is L-rhamnopyranosyl-${\beta}$-hydroxydecanoyl-${\beta}$-hydroxydecanoic acid and compound B is L-rhamnopyranosyl-L-rhamnopyranosyl-${\beta}$-hydroxydecanoyl-${\beta}$-hydroxydecanoic acid.

• Korean Journal of Medicinal Crop Science
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• v.3 no.2
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• pp.91-95
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• 1995

From the whole plants of Oldenlandia diffusa ursolic acid together with sterols, ${\beta}-sitosterol$ and its $3-0-{\beta}-D-glucoside$ were isolated and characterized mainly by means of spectroscopic methods. Based on the present findings, it may be considered that this plant may contribute to be a rich source for ursolic acid.

• KSBB Journal
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• v.17 no.2
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• pp.195-202
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• 2002

The production conditions of cellulolytic enzymes by a fungus, strain FJ1, were optimized using response surface analysis. The culture factors which largely affected the production of enzymes such as cultivation time, carbon source concentration, nitrogen source concentration, and composition ratio of carbon sources were employed. Optimizedconditions of the factors above corresponding to each cellulolytic enzyme production were as fellowing: CMCase production was obtained in the conditions of cultivation time of 5.4 days, carbon source concentration of 3.5%, nitrogen source concentration of 0.6%, and composition ratio of carbon sources of 52:48 (avicel:CMC), xylanase appeared in the conditions of 5.3 days, 3.5%, 0.8%, and 54:46, respectively, and $\beta$-glucosidase were 7.0 days, 5.0%, 1.0%, and 83:17, respectively, and avicelase were 6.5 days, 4.0%, 0.9%, and 64:36, respectively. The activities of CMCase, xylanase, p-glucosidase, and avicelase predicted by the response surface methodology were 33.5, 52.6, 2.88, and 1.84 U/mL, respectively, and $\beta$-glucosidase activity was enhanced up to 74% when compared to that obtained in the experimental conditions.

• 한국생물공학회:학술대회논문집
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• 2002.04a
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• pp.453-456
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• 2002

The production conditions of cellulolytic enzymes by Trichoderma sp. FJ1, were optimized using response surface analysis. The culture factors which largely affected to the production of enzymes such as cultivation time, carbon source concentration, nitrogen source concentration, and composition ratio of carbon sources were employed. Optimized conditions of the factors above to each cellulolytic enzyme production was as follow: CMCase production was obtained in the conditions of cultivation time of 5.4 days, 3.5% of carbon source concentration, 0.6% of nitrogen source concentration, and 52:48 (avicel:CMC) of composition ratio of carbon sources, respectively, xylanase appeared in the conditions of 5.3 day, 3.5%, 0.8%, and 54:46, respectively, and ${\beta}-glucosidase$ were 7.0 day, 5.0%, 1.0%, and 83:17, respectively, and avicelase were 6.5 day, 4.0%, 0.9%, and 64:36, respectively. The activities of CMCase, xylanase, ${\beta}-glucosidase$, and avicelase predicted by the response surface methodology were 33.5, 52.6, 2.88, and 1.84 U/ml, respectively, and ${\beta}-glucosidase$ was enhanced up to 74% compared to that obtained in the experimental conditions.