• Journal of Life Science
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• v.24 no.8
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• pp.915-926
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• 2014

The ribosome is a protein synthesizing machinery and a ribonucleoprotein complex that consists of three ribosomal RNAs (23S, 16S and 5S) and 54 ribosomal proteins in bacteria. In the course of ribosome assembly, ribosomal proteins (r-protein) and rRNAs are modified, the r-proteins bind to rRNAs to form ribonucleoprotein complexes which are folded into mature ribosomal subunits. In this process, a number of non-ribosomal trans-acting factors organize the assembly process of the components. Those factors include GTP- and ATP-binding proteins, rRNA and r-protein modification enzymes, chaperones, and RNA helicases. During ribosome biogenesis, they participate in the modifications of ribosomal proteins and RNAs, and the assemblies of ribosomal proteins with rRNAs. Ribosomes can be assembled from a discrete set of components in vitro, and it is notable that in vivo ribosome assembly is much faster than in vitro ribosome assembly. This suggests that non-ribosomal ribosome assembly factors help to overcome several kinetic traps in ribosome biogenesis process. In spite of accumulation of genetic, structural, and biochemical data, not only the entire procedure of bacterial ribosome synthesis but also most of roles of ribosome assembly factors remain elusive. Here, we review ribosome assembly factors involved in the ribosome maturation of Escherichia coli, and summarize the contributions of several ribosome assembly factors which associate with 50S and 30S ribosomal subunits, respectively.

• Journal of Life Science
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• v.23 no.3
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• pp.399-405
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• 2013

This study was carried out to analyze the effects on antioxidative, antidiabetic, and anti-inflammatory activities of Parthenocissus tricuspidata (PT) stem extracts. The total phenolic contents of hot water and ethanol extracts from PT stems were 61.5 mg TAE/g and 122.1 mg TAE/g, respectively. The antioxidative activities of hot water and ethanol extracts from PT stem were measured by using 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity and superoxide dismutase (SOD) assay. The DPPH radical scavenging activities of ethanol extract and butanol fraction were approximately 95% and 92% at 1 mg/ml, respectively, and the SOD activities of ethanol extract and butanol fraction were about 91% and 97% at 1 mg/ml, respectively. The DPPH radical scavenging and SOD activities of ethanol extract and butanol fraction from PT stem increased remarkably increased in a dose-dependent manner and were higher than in the hot water extracts. Compared to the acarbose, a known anti-diabetic drug, which was used as a positive control, the ${\alpha}$-glucosidase inhibitory capacity of PT stem showed a strong inhibitory rate in ethanol extract and in butanol and hexane fractions. We investigated the effect of hot water extract from PT stem on lipopolysaccharide (LPS)-induced nitric oxide (NO) production in RAW 264.7 cells. Hot water extract from PT stem inhibited LPS-induced NO production up to 40% at a treatment of 1 mg/ml. These results suggest that PT stem extracts have an effect on antioxidative, antidiabetic, and anti-inflammatory activities and thus have great potential as antidiabetic materials and a source for natural health products.

• Journal of Life Science
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• v.26 no.9
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• pp.1015-1021
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• 2016

5-fluorouracil (5-FU), a pyrimidine analog, is a widely used anticancer drug, which works through irreversible inhibition of thymidylate synthase. In the present study, it was investigated the anti-proliferative effects and molecular mechanisms of 5-FU using Ewing's Sarcoma CHP-100 Cells. The present data indicated that treatment of 5-FU to CHP-100 cells induced a G1 phase arrest of the cell cycle in a time-dependent manner. 5-FU-induced G1 arrest was correlated with the accumulation of the hypophosphorylated form of the retinoblastoma protein (pRB) and association of pRB with the transcription factors E2F-1 and E2F-4. Although 5-FU treatment did affect the levels of cyclin-dependent kinases, the levels of cyclin A and B were markedly down-regulated as compared with the untreated control group. In addition, 5-FU-induced G1 arrest of CHP-100 cells was also associated with the induction of apoptosis, as determined by apoptotic cell morphologies, degradation of poly(ADP-ribose) polymerase and Annexin V staining. Furthermore, 5-FU induced the loss of mitochondrial membrane potential with up-regulated pro-apoptotic Bax expression, down-regulated anti-apoptotic Bcl-2 expression and cytochrome c release from mitochondria to cytosol. Collectively, the data suggest that 5-FU is effective in inducing cell growth reduction and apoptosis, in part, by reducing phosphorylation of pRB and activating mitochondrial dysfunction in CHP-100 cells.

• Journal of Life Science
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• v.26 no.9
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• pp.1022-1026
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• 2016

In this study the hot water extract was prepared from Hydrocotyle sibthorpioides (Araliaceae) leaves and stems to study antioxidant activities and lipoxygenase inhibition. The extract showed the protective hydroxyl radical (-OH) which can damage virtually all types of macromolecules: carbohydrates, nucleic acids (mutations), lipids (lipid peroxidation), and amino acids. Hydroxyl radical scavenging activity of H. sibthorpioides was 78.6%. The extract showed strong activity against 1, 1- diphenyl 2-picrylhyorazyl (DPPH) which is a well-known radical and a trap (scavenger) for other radicals. DPPH scavenging activity of leaves of H. sibthorpioides was evaluated at 8.0 mg/ml was 86.0%. Lipoxygenases (LOXs) constitute a heterogeneous family of lipid peroxidizing enzymes capable of oxygenating polyunsaturated fatty acids to their corresponding hydroperoxy derivatives. The inhibitory effect of 15-LOX by H. sibthorpioides was assayed using a Morgan microplate assay. The extract of H. sibthorpioides was 55.5% inhibitory effects on the inhibition of LOX at 8.0 mg/ml. The IC₅₀ values for OH activity, DPPH activity, and LOX inhibition from leaves 5.23 mg/ml, 6.44 mg/ml, and 3.71 mg/ml, respectively. Antioxidative activity assay showed that the water extracts from leaf and stem had a strong reducing power. These results show that H. sibthorpioides has some phytochemical constituents which may be active against the free radicals (OH and DPPH) and lipoxygenase enzyme.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.9
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• pp.1515-1521
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• 2004

As one of the research series for the industrialization of sikhae, this study was evaluated the taste compounds present in different temperature conditions, $5^{\circ}C$, $20^{\circ}C$ and alternating temperature (stored at $5^{\circ}C$ after 10 days fermentation at $20^{\circ}C$), respectively. The changes in proximate compositions were negligible but the amounts of total sugar decreased during fermentation. The pH of sikhae products except the product fermented at $5^{\circ}C$, decreased during fermentation and was maintained at the rage of 3.8~4.4 after 10 days. The values of acidity, VBN and amino-N gradually increased with fermentation times and with increasing temperature condition in all products. Three organic acids (lactic, citric and malic acid) were disclosed as key compounds affecting the sourness in Alaska pollack sikhae. The result of taste value revealed that 6 amino acids having sweet and umami taste (aspartic acid, glutamic acid, alanine and lysine) and bitter taste (valine and methionine) as major amino acids affecting the taste of sikhae products, and increased with fermentation times. Hypoxanthine was the main component in ATP related compounds. Amino-N was comprised more over 50% of the Ex-N in sikhae products, and followed by total creatinine-N, TMAO-N and TMA-N in that order.

• Microbiology and Biotechnology Letters
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• v.38 no.3
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• pp.255-262
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• 2010

Strain BCNU 2001 was isolated from soil samples collected from Tea-baek Mountain area. The biochemical characteristics and 16S ribosomal RNA gene sequences of the isolate revealed that the strain belonged to the Pseudomonas aeruginosa. The supernatants had an antimicrobial effect on various kind of bacteria and fungi. Especially BCNU 2001 was able to greatly inhibit the growth of Micrococcus luteus, Proteus mirabilis, Proteus vulgaris, and Aspergillus niger, and its inhibition zone was measured as 18.5 mm against Micrococcus luteus, 19.0mm against Proteus mirabilis, 17.0mm against Proteus vulgaris, and 13.5 mm against Aspergillus niger, respectively. Hexane and dichloromethane extracts of BCNU 2001 exhibited significant activity against bacteria, and dichloromethane and ethylacetate extracts showed significant activity against fungi. Pseudomonas strain BCNU 2001 was also determined to have antimicrobial peptide against various microorganisms including Gram positive bacteria, Gram negative bacteria and fungi. The obtained results may provide preliminary support for the usefulness of Pseudomonas strain BCNU 2001.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.35 no.2
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• pp.196-200
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• 2002

In order to identify the feeding stimulants for flatfish, the feeding tests were conducted using some diets added the amino acids, nucleotides, betaine and TU and acid hydrolysates to basal diet formula, respectively, The feeding stimulant activities and synergistic effects of those compounds were evaluated by a bioassay method. The KH, a kind of acid hydrolysate, possessed a remarkable feeding stimulant activity. It's stimulant activities were increased up to the concentration of $1.05\%$ (w/v), and were independent of pH. The formulation of KH and glycine had a most synergistic effect, The feeding rate of diet with feeding stimulation was 1,4 fold than that of diet without one. The costs for optimum formulation of feeding stimulants were cheaper than some additives in diets. It suggest that the results can practically used in preparation of diet containing feeding stimulant effects for flatfish.

• KSBB Journal
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• v.24 no.4
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• pp.410-414
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• 2009

Single-nucleotide polymorphisms (SNPs) are the DNA sequences difference among the same species in the level of nucleic acids and are widely applied in clinical fields such as personalized medicine. The routine and labor-intensive methods to determine SNPs are performing the sequence homology search by using BLAST and navigating the trace of chromatogram files generated by high-throughput DNA sequencing machine by using Chromas program. In this paper, we developed SNPchaser, a web-based program for detecting SNPs substitution and heterozygosity existence, to improve the labor-intensive method in determining SNPs. SNPchaser performed sequence alignment and visualized the suspected region of SNPs by using user's reference sequence, AB1 files, and positional information of SNPs. It simultaneously provided the results of sequences alignment and chromatogram of relevant area of SNPs to user. In addition, SNPchaser can easily determine existence of heterozygosity in SNPs area. SNPchaser is freely accessible via the web site http://www.bioinformatics.ac.kr/SNPchaser and the source codes are available for academic research purpose.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.3
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• pp.288-293
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• 2008

In this study, we investigated the anticancer activity of Makgeoly (MG). MG was fractionated into four fractions by using solvent partition method, affording hexane (MGH), methanol (MGM), butanol (MGB) and aquous (MGA) soluble fractions. We determined the cytotoxicity of these four fractions in four kinds of cancer cell lines, such as HepG2, MCF-7, B16-F10 and HT29 by MTT assay. Among the various fractions, the MGM showed the strongest cytotoxic effects on all cancer cell lines. The morphological changes such as membrane shrinking and blebbing of cells were also observed by MGM treatment in HepG2 cell. In addition, we observed quinone reductase (QR) activity stimulating effects in all fraction layers of MG on HepG2 cells. QR activity increased approximately 2.6 and 2.1 times in MGM and MGH treated HepG2 cell at $100{\mu}g/mL$, respectively, compared to that in control value. Although further studies are needed, the present work could suggest that the fin of MG has a potential to be used as a chemopreventive agent against cancer.

• Korean journal of applied entomology
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• v.40 no.3
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• pp.219-226
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• 2001

To identity the composition and ratio of the sex pheromone in the asiatic leafroller, Archippus breviplicanus (Walsingham), which is a major pest on apple leaves, and to develop a monitoring system using this sex pheromone, abdominal tips of their virgin female during the calling period were extracted and analysed. The GC/GC-MS analysis revealed the following three compounds; (E)11-tetradecenyl acetate (E11-14: Ac), (Z)11-tetradecenyl acetate (Z11-14: Ac), and tetradecyl acetate(14: Ac) with the ratio of 56:22:22. Electroantennogram (EAG) assay was also conducted to examine biological activity of the components. The three components evoked significantly higher responses than hexane or air but there was no significant differences between the mixtures made by components. Field trapping experiments for determining the optimum blend, seasonal fluctuation and the optimum amount for male attracting were carried out over 4 years from 1997 to 2000. Although male moths were attracted to 8:2 and 7:3 between E11-14: Ac and Z11-14: Ac, their 7:3 blend was found to be the most effective. Archippus breviplicanus appears to occur three times a year in Korea. The optimum amount for monitoring was found to be 1mg per trap. 14: Ac, the third component, did not show synergistic effect on male moth attraction.