• Journal of the korean academy of Pediatric Dentistry
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• v.32 no.2
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• pp.357-369
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• 2005

Streptococci are Gram-positive, facultative anaerobes and have no catalase activities. Among mutans streptococci containing ${\alpha}-type$ hemolytic activity, S. mutans is a causative agent for dental caries. As well as acid production yielding the demineralization of tooth enamel, adherence and colonization of S. mutans to the teeth are also important for its virulence. These early colonization are accomplished by the bacterial fibrillar protein, Antigen I/II (Ag I/II) and glucosyltransferase (GTF). Therefore, Ag I/II and GTF are reasonable targets for the development of vaccine against S. mutans GS-5. The ag I/II and gtfD genes from S. mutans GS-5 were cloned and sequenced. Sequence analyses showed the nucleotides sequence of cloned genes had high homology to the sequences previously reported. The sequence alignment of 280 nucleotides between the cloned Ag I/II and the available sequence of the corresponding S. mutans GS-5 showed the perfect match. Comparing with the sequence of gtfD from S. mutans UA159, the corresponding nucleotide sequence of S. mutans GS-5 showed some mismatches and the mismatches introduced changes in four residues out of 105 amino acids, yielding four missense mutations.

• Food Science and Preservation
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• v.22 no.5
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• pp.744-750
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• 2015

The present study was designed to investigate the effects of hot water and ethanol extracts of Nelumbo nucifera Gaertner flower on lipid accumulation and reactive oxygen species (ROS) production during adipogenesis in 3T3-L1 cells. 3T3-L1 preadipocytes were treated with both hot water and ethanol extracts for up to 8 days following standard induction of differentiation. Regarding anti-adipogenic activity, compared with the control, the hot water and ethanol extracts significantly inhibited lipid accumulation (37.4 and 66.6%, respectively) and ROS production (46.4 and 46.8%, respectively) during adipogenesis in 3T3-L1 cells. Treatment with hot water and ethanol extracts significantly inhibited mRNA expression of peroxisome proliferator-activated receptor gamma ($PPAR{\gamma}$) and CCAAT/enhancer-binding protein alpha ($C/EBP{\alpha}$), thereby reducing the mRNA expression of adipocyte-specific fatty acid binding protein (aP2). Moreover, both the extracts significantly inhibited mRNA expression of NADPH oxidase (NOX4). Overall, our research suggests that N. nucifera Gaertner flower extracts might be a valuable source of bioactive compounds that exhibit anti-adipogenic activity and could have applications in the field of medicine and food industry.

• Journal of Life Science
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• v.15 no.4 s.71
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• pp.553-560
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• 2005

The stf (Salmonella typhimurium fimbriae) operon consisting of stfA(CDEFG assumes to encode putative fimbriae. The complete stf operon is existed in S. typhimurium and S. choleraesuis, whereas it is absent in S. typhi. Analyses of the amino acid residues between major subunit StfA of the Stf fimbriae and those of known other fimbriaes suggested that Stf belongs to class I type fimbriae. Through comparison of StfD chaperone with the other fimbrial chaperones, and of C-terminus in subunits of Stf fimbriae, it belongs to FGS (with a short Fl-G1 loop) subfamily. In order to investigate the expression of stf operon, we have constructed a Salmonella strain containing a chromosomal stfA::lacZYA transcriptional fusion, resulting in S. typhimurium $_X8532$. The strain $_X8532$ lacked the expression of \beta-galactosidase$ under normal culture conditions. However, with longer incubation time of the S. typhimurium $_X8532$, we have isolated 21 individual strains exhibiting $Lac^+$ phenotype. $Lac^+$ phenotype was appeared as approximately 0.03 frequency per generation. All isolates expressed lacZ constitutively in the various environmental conditions. Various global regulatory proteins including RpoS, OmpR, and CpxR were not involved in the regulation of the stf operon. A S. typhimurium $_X8661$ mutant lacking stfAC function attenuated 6.7 folds more than that of wild type $_X3761$ in the mouse virulence test, suggesting in the somehow involved in the Salmonella pathogenesis.

• Korean Journal of Food Science and Technology
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• v.46 no.4
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• pp.498-504
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• 2014

Allium senescens L. is perennial plant of the Liliaceae family that grows throughout Korea. In this study, we investigated the effect of Allium senescens L. methanol extracts on reactive oxygen species (ROS) production and lipid accumulation during adipogenesis. Our results indicated that 1,1-diphenyl-2-picrylhydrazyl radical scavenging activity of Allium senescens L. methanol extracts increased in a dose-dependent manner. Allium senescens L. methanol extracts suppressed ROS production and lipid accumulation during adipogenesis. In addition, Allium senescens L. methanol extracts inhibited the mRNA expression of the pro-oxidant enzyme, such as G6PDH and lead to a reduction in the mRNA levels of the transcription factors, such as sterol regulatory element binding proteins 1c, peroxisome proliferator-activated receptor ${\gamma}$, and CCAAT/enhancer-binding proteins ${\alpha}$. These results indicate that Allium senescens L. methanol extracts inhibit adipogenesis by modulating ROS production associated with ROS-regulating genes and directly down-regulating adipogenic transcription factors.

• Journal of Life Science
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• v.26 no.2
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• pp.265-274
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• 2016

Toxin-antitoxin (TA) systems are ubiquitous genetic modules that are evolutionally conserved in bacteria and archaea. TA systems composed of an intracellular toxin and its antidote (antitoxin) are currently classified into five types. Commonly, activation of toxins under stress conditions inhibits diverse cellular processes and consequently induces cell death or reversible growth inhibition. These effects of toxins play various physiological roles in such as regulation of gene expression, growth control (stress response), programmed cell arrest, persister cells, programmed cell death, phage protection, stabilization of mobile genetic elements or postsegregational killing of plasmid-free cells. Accordingly, bacterial TA systems are commonly considered as stress-responsive genetic modules. However, molecule screening for activation of toxin in TA system is available as development of antimicrobial agents. In addition, cytotoxic effect induced by toxin is used as effective cloning method with antitoxic effect of antitoxin; consequently cells containing cloning vector inserted a target gene can survive and false-positive transformants are removed. Also, TA system is applicable to efficient single protein production in biotechnology industry because toxins that are site-specific ribonuclease inhibit protein synthesis except for target protein. Furthermore, some TA systems that induce apoptosis in eukaryotic cells such as cancer cells or virus-infected cells would have a wide range of applications in eukaryotes, and it will lead to new ways of treating human disease. In this review, we summarize the current knowledge on bacterial TA systems and their applications.

• Journal of Life Science
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• v.23 no.11
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• pp.1404-1408
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• 2013

(-)-Epigallocatechin-3-gallate (EGCG), a green tea polyphenol, has been shown to have strong antibacterial, antiviral, antioxidant, anti-inflammatory, and chemopreventive effects. However it is unknown whether EGCG can recover alcohol-associated pancreatitis. The aim of this study was to investigate the effects of EGCG on pancreatic enzyme activities and the expressions of pancreatic regenerating related markers, such as adenosine monophosphate-activated protein kinase (AMPK), raf-1 kinase inhibitor protein (RKIP), and Regenerating gene 1 (Reg1), in mice pancreatic primary acinar cells. Our results revealed that activities of ${\alpha}$-amylase and chymotrypsin were significantly increased in the cells treated with ethanol compared to the untreated control cells; however, the increased activities of both enzymes were markedly reduced by pretreatment with EGCG. Phosphorylation of AMPK and total expression of RKIP were decreased in the ethanol-treated primary acinar cells; however, these were both significantly increased in the EGCG-pretreated cells. In addition, when EGCG was treated, expression of Reg1 was markedly increased compared with that of the control or the ethanol-treated primary acinar cells, demonstrating that EGCG can modulate pancreatic regenerating related genes. Therefore, our findings suggest that EGCG may have therapeutic utility in the prevention or treatment of alcohol-associated pancreatitis.

• Korean Journal of Food Science and Technology
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• v.52 no.2
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• pp.191-199
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• 2020

The purpose of this study was to isolate novel lactic acid bacteria to ferment mulberry leaf extract (MLE) and to investigate its anti-diabetic effect. Lactobacillus plantarum SG-053 isolated from gatkimchi was selected to ferment MLE because it exhibited high α-glucosidase inhibitory activity (96.8%) and enhanced the content of 1-deoxynojirimycin (DNJ), an anti-diabetic substance, in fermented MLE up-to 2.2 times. MLE fermented with L. plantarum SG-053 (FMLE) showed growth promoting activity against L6 myotubes and increased the gene expressions of IRS-1, PI3K p85α, and GLUT-4 up-to 1.4, 2.2, and 1.4 times, respectively, and 2-deoxyglucose uptake up-to 40.7%. In rat skeletal muscle tissue, the expressions of PI3K p85α and GLUT-4 increased by 6.4 and 2.1 times, respectively. These results suggest that L. plantarum SG-053 could enhance the DNJ content of MLE by fermentation and that FMLE is effective in ameliorating insulin resistance via activation of the insulin signaling pathway.

• Journal of Sericultural and Entomological Science
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• v.53 no.2
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• pp.92-96
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• 2015

It is known that silk protein supports effectively proliferation of cell such as insect cell and hybridoma cell. Although there are many varieties of Bombyx mori silkworm, the effect of silkworm varieties on cell proliferation has not been considered in detail. We studied that characteristics of silk cocoon obtained from Baegokjam, Kumokjam, Daeseongjam silkworm varieties and whether silk protein affected cell proliferation or not. Silk sericin was prepared under high temperature and high pressure condition. Silk fibroin was prepared using $CaCl_2:H_2O:EtOH$ with different dissolution time. As a result, there are differences in silk cocoon from different silkworm varieties about cell proliferation. The proliferation was accelerated in the presence of Baegokjam silk sericin and Kumokjam silk fibroin with 5hr dissolution time. We expect that silk proteins could be a preferable culture medium supplement for stimulating the proliferation of cell. Then, this results suggest silk as a new material for medium supplement replacing with fetal bovine serum.

• Journal of the Korea Organic Resources Recycling Association
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• v.29 no.3
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• pp.27-33
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• 2021

CO I gene sequence analysis was applied to earthworms that had been used as test animals in toxicity test in Institute of Kyeongbook Agrochemicals and earthworms used as vermicomposting agents in the farm of Youngdong province to identify their species names. In terms of molecular species, the former was identified as Eisenia fetida and the latter was Eisenia andrei. Cocoons produced from Eisenia fetida was more than those from Eisenia andrei. And No. of adults developed from eggs of Eisenia fetida was more or less higher than those developed from eggs of Eisenia andrei. These results were contradictory to previous reports on two Eisenia spp.. When Eisenia fetida was crossed with Eisenia andrei, hybridized eggs were produced and adults were developed from those eggs, but cocoons and adults were much less than those from non-crossed Eisenia fetida or Eisenia andrei. This indicated that two Eisenia spp. were not distinctly different biological species because there was no complete 'reproductive isolation' between Eisenia fetida and Eisenia andrei. However, this also meant that Eisenia fetida and Eisenia andrei had already been on the tract of speciation.

• Food Science and Preservation
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• v.30 no.3
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• pp.502-513
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• 2023

This study aimed to evaluate the anti-adipogenic and anti-inflammation effects of extract from Maclura tricuspidata twig fermented with Ganoderma lucidum mycelium (EMFG) in 3T3-L1 preadipocytes. 3T3-L1 adipocytes were treated with 100, 200, 300 ㎍/mL of EMFG. The result showed that EMFG dose-dependently inhibited the accumulation of intracellular lipid content in differentiated 3T3-L1 adipocytes and enhanced increase of adiponectin release and inhibition of leptin release. EMFG treatment reduced expression of adipogenic transcriptional factor such as peroxisome proliferator-activated receptor γ (PPARγ), CCAAT-enhancer-binding protein α (C/EBPα). EMFG also decreased production of lipopolysaccharide (LPS)-induced inflammatory cytokine [tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6) and monocyte chemoattractant protein-1 (MCP-1)] and the protein expression of cyclooxygenase-2 (COX-2) and inducible NOS (iNOS) in differentiated 3T3-L1 adipocytes. The study demonstrated that EMFG inhibited adipogenesis and inflammation in a dose-dependent manner. These findings suggest that EMFG may have potential as an anti-obesity and anti-metabolic disease agent that works by inhibiting adipogenesis and inflammation.