• Journal of Life Science
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• v.24 no.9
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• pp.988-994
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• 2014

The effluents of chemical and petroleum industries often contain non-biodegradable aromatic compounds, with phenol being one of the major organic pollutants present among a wide variety of highly toxic organic chemicals. Phenol is toxic upon ingestion, contact, or inhalation, and it is lethal to fish even at concentrations as low as 0.005 ppm. Phenol biodegradation has been studied in detail using bacterial strains. However, these microorganisms suffer from substrate inhibition at high concentrations of phenol, whereby growth is inhibited. A phenol-degrading bacterium, P21, was isolated from oil-contaminated soil. The phenotypic characteristics and a phylogenetic analysis indicated the close relationship of strain P21 to Rhodococcus pyridinovorans. Phenol biodegradation by strain P21 was studied under shaking condition. The optimal conditions for phenol biodegradation by strain P21 were 0.09% $KNO_3$, 0.1% $K_2HPO_4$, 0.3% $NaH_2PO_4$, 0.015% $MgSO_4{\cdot}7H_2O$, 0.001% $FeSO_4{\cdot}7H_2O$, initial pH 9, and $20-30^{\circ}C$, respectively. When 1,000 ppm of phenol was added to the optimal medium, the strain P21 completely degraded it within two days. Rhodococcus pyridinovorans P21 could grow in up to 1,500 ppm of phenol as the sole carbon source in a batch culture, but it could not grow in a medium containing above 2,000 ppm. Moreover, strain P21 could utilize toxic compounds, such as toluene, xylene, and hexane, as a sole carbon source. However, no growth was detected on chloroform.

• Journal of Life Science
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• v.34 no.5
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• pp.304-312
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• 2024

This study was conducted to characterize strain Y10, isolated from discarded chicken feathers. Strain Y10 was identified as Bacillus amyloliquefaciens through phenotypic and 16S rRNA gene analysis. B. amyloliquefaciens Y10 exhibited plant growth-promoting activities, including the production of fungal cell-degrading enzymes (cellulase, lipase, protease, and pectinase), siderophores, ammonia, and indoleacetic acid. Furthermore, strain Y10 was able to inhibit the mycelial growth of several phytopathogenic fungi. When 0.1% sucrose as a carbon source and 0.05% casein as a nitrogen source were added to the basal medium, adjusted to pH 10, and cultured at 35℃, the degradation rate of chicken feathers by strain Y10 was about two times higher than that of the basal medium, with the feathers almost completely degraded in four days. Strain Y10 also degraded various keratin substrates, including duck feathers, wool, and human nails. It was confirmed that the feather hydrolyzates prepared using strain Y10 exhibited antioxidant activities, such as 1,1-diphenyl-2-picrylhydrazyl radical scavenging activity (EC₅₀ = 0.38 mg/ml) and superoxide dismutase-like activity (EC₅₀ = 183.7 mg/ml). These results suggest that B. amyloliquefaciens Y10 is a potential candidate for the development of bioinoculants and feed additives applicable to the agricultural and livestock industries, as well as the microbiological treatment of keratin waste.

• Journal of Life Science
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• v.21 no.11
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• pp.1631-1635
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• 2011

The capability of synthesizing polyphenol glycosides was examined using recombinant amylosucrase from the hyperthermophilic bacterium Deinococcus geothermalis. Based on the action mode of amylosucrase, sucrose and twenty-one polyphenols were used as a donor and acceptors respectively. The transglycosylation reaction by amylosucrase produced one or two major polyphenol glycosides depending on the type of polyphenols used. The synthesized polyphenol glycosides were detected by thin-layer chromatography. The structures of the newly synthesized polyphenol glycosides were predicted based on the transglycosylation mechanism of the enzyme. According to the acceptability of the polyphenols, the structural characteristics of polyphenol as an efficient acceptor were evaluated. The results indicate that amylosucrase is an efficient catalyst for the enzymatic synthesis of polyphenol glycosides, which have high potentials in food, cosmetics, and pharmaceutical industries.

• Journal of Ginseng Research
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• v.40 no.1
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• pp.68-75
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• 2016

Background: The study of phenolic compounds profiles and antioxidative activity in ginseng fruit, leaves, and roots with respect to cultivation years, and has been little reported to date. Hence, this study examined the phenolic compounds profiles and 2, 2-diphenyl-1-picrylhydrazyl (DPPH) free-radical-scavenging activities in the fruit, leaves, and roots of Korean ginseng (Panax ginseng Meyer) as a function of cultivation year. Methods: Profiling of 23 phenolic compounds in ginseng fruit, leaves, and roots was investigated using ultra-high performance liquid chromatography with the external calibration method. Antioxidative activity of ginseng fruit, leaves, and roots were evaluated using the method of DPPH free-radical-scavenging activity. Results: The total phenol content in ginseng fruit and leaves was higher than in ginseng roots (p < 0.05), and the phenol content in the ginseng samples was significantly correlated to the DPPH free-radical-scavenging activity ($r=0.928^{****}$). In particular, p-coumaric acid ($r=0.847^{****}$) and ferulic acid ($r=0.742^{****}$) greatly affected the DPPH activity. Among the 23 phenolic compounds studied, phenolic acids were more abundant in ginseng fruit, leaves, and roots than the flavonoids and other compounds (p < 0.05). In particular, chlorogenic acid, gentisic acid, p- and m-coumaric acid, and rutin were the major phenolic compounds in 3e6-yr-old ginseng fruit, leaves, and roots. Conclusion: This study provides basic information about the antioxidative activity and phenolic compounds profiles in fruit, leaves, and roots of Korean ginseng with cultivation years. This information is potentially useful to ginseng growers and industries involved in the production of high-quality and nutritional ginseng products.

• Journal of Microbiology and Biotechnology
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• v.22 no.12
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• pp.1698-1704
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• 2012

Resveratrol, or its glycoside form piceid, is a dietary antioxidant polyphenolic compound, found in grapes and red wine that has been shown to have protective effects against cardiovascular disease. However, very low water solubility of the compound may limit its application in the food and pharmaceutical industries. The amylosucrase (AMAS) of Alteromonas macleodii Deep ecotype was expressed in Escherichia coli and showed high glycosyltransferase activity to produce the glucosyl piceid when piceid was used as an acceptor. The conversion yield of piceid glucoside was 35.2%. Biotransformation using culture of the E. coli harboring the amas gene increased the yield up to 70.8%. The transfer product was purified by reverse phase chromatography and recycling preparative HPLC, and the molecular structure of the piceid glucoside was determined using NMR spectroscopy. The piceid glucoside was identified as glucosyl-${\alpha}$-($1{\rightarrow}4$)-piceid. The solubility of glucosyl piceid was 5.26 and 1.14 times higher than those of resveratrol and piceid, respectively. It is anticipated that dietary intake of this compound is more effective by enhancing the bioavailability of resveratrol in the human body because of its hydrophilic properties in the intestinal fluid.

• Journal of Life Science
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• v.13 no.4
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• pp.522-528
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• 2003

The RAD4 gene of Saccharomyces cerevisiae is essential for the incision step of UV-induced excision repair. A yeast RAD4 gene has been previously isolated by functional complementation. In order to identify the RAD4 homologous gene from fungus Coprinus cinereus, we have constructed cosmid libraries from electrophoretically separated chromosomes of the C. cinereus. The 13 C. cinereus chromosomes were resolved by pulse-field gel electrophoresis, hybridized with S. cerevisiae RAD4 DNA, and then isolated homologous C. cinereus chromosome. The insert DNA of the RAD4 homolog was contained 3.2 kb. Here, we report the characterization of fungus C. cinereus homolog of yeast RAD4 gene. Southern blot analysis confirmed that C. cinereus contains the RAD4 homolog gene and this gene exists as a single copy in C. cinereus genome. When total RNA isolated from C. cinereus cells was hybridized with the 1.2 kb PvuII DNA fragment of the S. cerevisiae RAD4 gene, a 2.5 kb of transcript was detected. In order to investigation whether the increase of transcripts by DNA damaging agent, transcripts levels were examined after treating the cells. The level of transcript did not increase by untraviolet light (UV). This result indicated that the RAD4 homologous gene is not UV inducible gene. Gene deletion experiments indicate that the RAD4 homologous gene is essential for cell viability.

• Korean Journal of Environmental Biology
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• v.36 no.4
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• pp.687-693
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• 2018

The active development of the global marine trade industries has been known to increase the inflows of marine invasive species and harmful organisms into the ecosystem, and the marine ecological disturbances. One of these invasive species, Ciona robusta, has now spread to the Korea Strait, the East Sea, and Jeju Island in connection with the climate change but not the Yellow Sea in Korea. Currently, the spread and distribution of C. robusta is increasingly damaging aquaculture and related facilities. Therefore, this study aims to identify the spread of C. robusta and potential habitats and to secure a data for the prevention of effective management measures due to climate change as well as damage the reduction in future through the prediction of spread. We used environmental variables in BioOracle. Also, the potential habitat and distribution of C. robusta was predicted using MaxEnt, a species distribution model. Two different RCP scenarios(4.5 and 8.5) were specified to predict the future distributions of C. robusta. The results showed that the biggest environmental factor affecting the distribution of C. robusta was the salinity as well as the highest distribution and potential habitats existent in the East Sea and around Jeju Island.

• Journal of the Korean Society for Marine Environment & Energy
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• v.19 no.3
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• pp.236-245
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• 2016

Because microalgae represent high growth rate than terrestrial plants, and it can accumulate significant lipid and carbohydrate content, and other bioactive compounds such as carotenoid and polyphenol in their body, it has been considered as one of the promising resources in bio-energy, and other industries. Although many studies has been performed about the microalgae-derived biochemical accumulation under various abiotic conditions such as different temperatures, salinities and light intensities, the studies about simultaneous effect of those parameters has rarely been performed. Therefore, this study focused on evaluation of simultaneous effect of different salinity (10, 30, 50 psu) and temperatures (20, 25, $30^{\circ}C$) on the changes of biomass, lipid, starch and photosynthetic pigment accumulation. As results, the highest growth rate was achieved at $30^{\circ}C$ and 30 psu in the both algal cultures, and the photosynthetic pigment, chlorophyll a and total carotenoid content, were increased in a temperature-dependent manner. The accumulation of lipid and starch contents exhibited different aspects under different combinations of temperature and salinity. From the results, it is suggested that the changes of microalgal lipid and starch accumulation under different salinities may be affected by the different temperatures.

• Fisheries and Aquatic Sciences
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• v.14 no.1
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• pp.1-10
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• 2011

This study was conducted to obtain hydrolysates with potent antioxidative activity from rockfish skin gelatin. Gelatin was extracted under high temperature/high pressure using a two-step enzymatic hydrolysis with commercial enzymes such as Alcalase, Flavourzyme, Neutrase, and Protamex. The second rockfish-skin gelatin hydrolysate (SRSGH) was prepared by further incubating the first gelatin hydrolysate (FRSGH), which had been hydrolyzed with Alcalase for 1-h (FRSGH-A1), with Flavourzyme for 2-h (SRSGH-F2). The second gelatin hydrolysate showed higher antioxidative activity of 3.72 as measured by a Metrohm Rancimat and superior angiotensin I-converting enzyme (ACE) inhibiting activity of 0.82 mg/mL. Compared with the gelatin, the relative proportion in SRSGH-F2 was markedly decreased in the 100-kDa peak, whereas it was increased in that less than 100-kDa. The amino acid composition of SRSGH-F2 was rich in glycine (25.9%), proline (10.8%), alanine (9.1%), and glutamic acid (9.1%). In contrast, it was poor in cystine (not detected), methionine (1.6%), tyrosine (0.4%), hydroxylysine (0.9%), and histidine (0.9%). In recent years, demand for natural functional foods has been increasing, and SRSGH-F2 can be used as a functional food ingredient in the food industries. However, further detailed studies on SRSGH-F2 with regard to its antioxidant activity in vivo and the various antioxidant mechanisms are needed.

• Journal of Gifted/Talented Education
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• v.21 no.2
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• pp.357-372
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• 2011

Enhancing individual competitiveness as well as national competitiveness by fostering creative human resources are one of the important visions of the nation. Thus, fostering creative human resources should be important mission of the nation. The purpose of this study is to identify what type of creative human resources is possible, based on Korean culture and background. Qualitative research experts was given to six experts of academics, institutes, and industries in science, humanities, social science, and art. The result indicated that key words for fostering creative human resources in Korea are 'fusion' and 'integration', and the definition and factors of creative human resources as well as educational strategy to foster it depend upon them. How to foster creative human resources in life-long learning also discussed.