• Journal of Life Science
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• v.14 no.4
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• pp.644-649
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• 2004

During plant development, active gibberellins (GAs) control many aspects of plant growth and development including seed germination, stem elongation, flower induction, anther development and seed growth. To understand the biosynthesis and functional role of active GAs in high plants, this study investigated GA 3$\beta$-hydroxylase gene en-coding $GA_1$ and$GA_4$ catalizing last step in GA biosynthetic pathway. The antisense GA 3$\beta$-hydroxylase gene was inserted into expression vector, pIG121-Hm. Calli derived from mature seeds of rice (Oryza satiiva L. cv. Donjinbyeo) were co-cultivated with Agrohacterium tumefaciens EHA101 earring a pIG121-Hm containing hygromycin resistance ($Hyg^r$) and antisense GA 3$\beta$-hydroxylase gene. Seventeen transgenic plants obtained inhibiting GA 3$\beta$-hydroxylase. Transgenic plants had shorter plant height more than that of the Dongjinbyeo. Stable integration of antisense GA 3$\beta$-hydroxylase gene was confirmed by polymerase chain reaction of genomic DNA isolated from the leaf organs of the $T_o$ generation.

• YAKHAK HOEJI
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• v.46 no.6
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• pp.459-465
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• 2002

$\beta$-l, 3-glucans are well known to enhance the immune reactions, resulting in antitumor, antibacterial, antiviral, anticoagulatory and wound healing activities. $\beta$-1, 3-glucans have various activities depending on molecular weight, degree of branching, conformation, water-solubility and intermolecular association. However, the $\beta$-1, 3-glucans linked backbone structure is essential and $\beta$-D-glucopyranosyl units are required for immunopotentiating activities. In this study, we tested the immunophamacological activities of insoluble $\beta$-1, 3-glucan from Agrobacterium sp. R259 KCTC 10197BP and confirmed the following activities: (1) IFN-${\gamma}$ production in PBMCs in the presence or in the absence of PHA, LPS, IL-18, and IL-12; (2) the induction of various cytokines in the spleen and thymus; (3) the adjuvant effect on the antibody production; (4) the cytotoxic and antitumor effects on cell lines and ICR mice. These results strongly suggest that $\beta$-1, 3-glucan from Agrobacterium sp. R259 KCTC 10197BP possesses various immunopharmacologica1 activities.

• Archives of Pharmacal Research
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• v.22 no.1
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• pp.81-85
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• 1999

Nine flavonoids (1-9) were isolated from the leaves of Morus alba (Moraceae). The structures of compounds were determined to be kaempferol-3-O-$\beta$-glucopyranoisde (astragalin, 1) kaempferol-3-O-(6"-O-acetyl)-$\beta$-D-glucopyranoside (2), quercetin-3-O-(6"-O-acetyl)-$\beta$-D-glucopyranoside (3), quercetin-3-O-$\beta$-D-glucopyranoside (4), kaempferol-3-O-$\alpha$-L-rhamnopyranosyl-(1 6)-$\beta$-D-glucopyranoside (5), quercetin-3-O-$\alpha$-L-rhamnopyranosyl-(1 6)-$\beta$-D-glucopyranoside (rutin, 6), quercetin-3-O-$\beta$-D-glucopyranosyl-(1 6)-$\beta$-D-glucopyranoside (7), quercetin-3,7-di-O-$\beta$-D-glucopyranoside (8) and quercetin (9) on th basis of spectroscopic and chemical studies. Compounds 7 and 9 exhibited significant radical scavenging effect on 1,1-diphenyl-2-picryl-hydrazyl radical.

• Microbiology and Biotechnology Letters
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• v.23 no.3
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• pp.311-315
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• 1995

Assay conditions for screening of $\beta$-1,3-glucan synthase inhibitor were evaluated. Cells in the beginning of mid-log phase showed the highest activity of the $\beta$-1,3-glucan synthase. Cells permeabilized with 1% digitonin treatment could be used as a good crude enzyme source for convenient screening of the $\beta$-1,3-glucan synthase inhibitors. Calcofluor white (0.125% in final) and papulacandin B (25 $\mu$g/ml) inhibit 90% and more than 50% of the $\beta$-1,3-glucan synthase activity, respectively. Cells grown at 37$\circ$C showed higher enzyme activity than those of 25$\circ$C. Catalytic factor of the $\beta$-1,3-glucan synthase was solubilized from particulated membrane preparations, holoenzyme, by extracting with 0.00938% CHAPS.

• Microbiology and Biotechnology Letters
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• v.37 no.2
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• pp.99-104
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• 2009

The $\beta$-glucosidase gene from Streptomyces coelicolor A3(2) was cloned and expressed in Escherichia coli. The ORF consisted of 1377 nucleotides encoding 51 kDa in a predicted molecular weight. Effects of pH indicated that the $\beta$-glucosidase showed similar activity using $\alpha$-pNPG($\rho$-nitrophenyl-$\alpha$-D-glucopyranoside), $\beta$-pNPG($\rho$-nitrophenyl-$\beta$-D-glucopyranoside), and $\beta$-pNPF($\rho$-nitrophenyl-$\beta$-D-fucopyranoside) at range of pH 3 to 10, and high activity using $\beta$-pNPGA ($\rho$-nitrophenyl-$\beta$-D-galactopyranoside) from pH 5 to 10, especially, 3.3 times higher activity at pH 9. Effects of temperature indicated that the $\beta$-glucosidase showed low activity using $\alpha$-pNPG, $\beta$-pNPG, and $\beta$-pNPF from $20^{\circ}C$ to $70^{\circ}C$, and increased activity using $\beta$-pNPGA from $30^{\circ}C$ to $50^{\circ}C$, 1.8 times higher activity at $50^{\circ}C$ than at $30^{\circ}C$. According to activity determination of other substrates, the enzyme was active on daidzin, genistin, and glycitin, inactive on esculin and apigenin-7-glucose. The EDTA and DTT as reducing agents inhibited $\beta$-glucosidase activity, but SDS and mercaptoethanol did not inhibit. Monovalent or divalent metal ions such as $MnSO_4$, $CaCl_2$, KCl, and $MgSO_4$ did not inhibited $\beta$-glucosidase activity. $CuSO_4$ and NaCl showed low inhibition, and $ZnSO_4$ inhibited 3.3 times higher than control.

• Microbiology and Biotechnology Letters
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• v.40 no.1
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• pp.50-56
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• 2012

The Wnt/${\beta}$-catenin signaling pathway regulates diverse developmental processes and adult tissue homeostasis. Inappropriate regulation of this pathway has been associated with human diseases, such as cancers, osteoporosis, and Alzheimer's disease. Using a cell-based chemical screening with natural compounds, we discovered silybin, a plant flavonoid isolated from the Silybum marianum, which activated the Wnt/${\beta}$-catenin signaling pathway in a synergy with Wnt3a-conditioned medium (Wnt3a-CM). In the presence of Wnt3a-CM, silybin up-regulated ${\beta}$-catenin response transcription (CRT) in HEK293-FL reporter cells and 3T3-L1 preadipocytes through stabilization of intracellular ${\beta}$-catenin protein. Silybin and Wnt3a-CM synergistically reduced expression of important adipocyte marker genes including peroxisome-proliferator-activated $receptor{\gamma}$ ($PPAR{\gamma}$) and CAATT enhancer-binding protein ${\alpha}$ (C/$EBP{\alpha}$) in 3T3-L1 preadipocytes, accompanied by the activation of Wnt/${\beta}$-catenin signaling pathway. Taken together, our findings indicate that silybin is a small-molecule synergist of the Wnt/${\beta}$-catenin signaling pathway and can be used as a controllable reagent for investigating biological processes that involve the Wnt/${\beta}$-catenin signaling pathway.

• Biotechnology and Bioprocess Engineering:BBE
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• v.5 no.3
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• pp.215-218
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• 2000

Sialytrisaccharides based on $\beta$-galactosyldisaccharides were synthesized using $\beta$-galactosidase and trans-sialidase in one pot. Using $\beta$-galactosidase from Bacillus Ciculans and trans-sialidase from Trypanosoma cruzi simulaneously, 6mM sialyltrisaccharides composed of about 95% NeuAc$\alpha$(2,3)Gal$\beta$(1,4)GlcNAc and 5% NeuAc$\alpha$(2,3)Gal$\beta$(1,6)GlcNAc were produced from a reaction mixture containing 25mM o-nitropheny1-$\beta$-D-galsctolneuraminic acid. One beauty of this reaction was that a secondary hydrolysis of the disaccharide intermediate occurring between the activated galactopyranoside and N-acetylgucosamine was prevented. Using $\beta$-galactosidase from Escherichia cloi and the same trans-sialidase, 15mM sialyltrisaccharides composed of about 90% NeuAc$\alpha$(2,3)Gal$\beta$(1,6)GlcNac and 10% NeuAc$\alpha$(2,3)Gal$\beta$(1,4)GlcNAc were produced from a reaction misture containing 400nM galactose, 800nM N-acetylglucosylation rection between galactose and N-actylgucosamine was diminant since the disaccharide intermediate mainly resulted sreulted in the silylated product.

• Toxicological Research
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• v.23 no.3
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• pp.197-205
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• 2007

Cancer metastasis is a major determinant of cancer patient mortality. Mounting evidence favors a strong positive role for $TGF-{\beta}$ in human cancer progression. The complex pattern on cross-talk of $TGF-{\beta}$ and the related other signaling pathways is an important area of investigation that will ultimately contribute to understanding of the bifunctional role of $TGF-{\beta}$ in cancer progression. This review summarizes some of the current understanding of $TGF-{\beta}$ signaling with a major focus in its contribution to the tumor cell invasion and metastasis. Five issues are addressed in this review: (1) $TGF-{\beta}$ signaling, (2) $TGF-{\beta}$ and EMT, (3) $TGF-{\beta}$ and MMP, (4) $TGF-{\beta}$ and Ras, and (5) Role of $TGF-{\beta}$ in invasion and metastasis. Due to the bifunctional cellular effects of $TGF-{\beta}$, as a tumor promoter and a tumor suppressor, more precisely defined $TGF-{\beta}$ signaling pathways need to be elucidated. According to the current literature, $TGF-{\beta}$ is clearly a major factor stimulating tumor progression through a complex spectrum of the interplay and cross-talk between various signaling molecules. Understanding the role of $TGF-{\beta}$ in invasion and metastasis will provide valuable information on establishing strategies to manipulate $TGF-{\beta}$ signaling which should be a high priority for the development of anti-metastatic therapeutics.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.56 no.3
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• pp.284-291
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• 2011

Varietal and annual variations in the contents of ${\beta}$-glucan fractions per weight grain samples were examined in sixteen covered and eighteen naked barley and five oat cultivars developed in Korea. Also, the effect of pearling on ${\beta}$-glucan content was investigated. Average contents of total, soluble and insoluble ${\beta}$-glucan fractions were 5.25, 3.72, and 1.53%, respectively, in covered barley, and 5.86, 3.51, and 2.35%, respectively, in naked barley. Soluble ${\beta}$-glucan content was higher in covered barley, though total ${\beta}$-glucan content higher in naked barley. The total and insoluble ${\beta}$-glucan contents were higher in pearled grains. Total ${\beta}$-glucan content was higher in waxy barley than in non-waxy barley. Duwonchapssalbori, a two-rowed and waxy naked barley cultivar, was highest in total, soluble and insoluble ${\beta}$-glucan contents. Highly significant positive correlations were observed between total ${\beta}$-glucan and soluble ${\beta}$-glucan contents both in covered and naked barley. There were significant annual variations in total ${\beta}$-glucan content in barley. Average contents of total, soluble and insoluble ${\beta}$-glucans of oat cultivars were 4.33, 3.44, and 0.89%, respectively. Contents of all fractions of ${\beta}$-glucans were higher in barley than in oat. These results would be useful for the breeding of high ${\beta}$-glucan variety and also for the use barley and oat as valueadded food ingredients.

• Journal of the Korean Ceramic Society
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• v.23 no.3
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• pp.1-8
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• 1986

The preparation and electrical conductivity of $\beta$-$Al_2O_3$ are investigated as a function of $Na_2O$ content from the-oretical composition of $\beta$-$Al_2O_3$ to that of $\beta$"-$Al_2O_3$. $\beta$-$Al_2O_3$ $\beta$"$Al_2O_3$$\alpha$-Al2O3 and ${\gamma}$-NaAlO2 phases appear in the calcined powder at 125$0^{\circ}C$ for 2 hours. The majoity phase is $\beta$-$Al_2O_3$ in sintered specimens at 155$0^{\circ}C$ and 1$650^{\circ}C$ for 30 mins respectively and ${\gamma}$-4NaAlO_2$ phase also exists when Na2O content is over 10.39w/o ${\gamma}$-4NaAlO_2$ phase does not affect the grain growth of $\beta$-$Al_2O_3$ in sintering at 155$0^{\circ}C$ but acts as a reactive liquid for the abnormal grain growth of $\beta$-$Al_2O_3$in sintering at 1$650^{\circ}C$ The electrical conduction of $\beta$-$Al_2O_3$is predominated by 4Na^+$ ion. Contribution of ionic con-ductivity to total conductivity is gradually decreased with increasing temperature at given oxygen pressure and to -tal conductivity is increased by positive hole due to interstitial oxygen with increasing oxygen pressure.