• Journal of the East Asian Society of Dietary Life
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• v.17 no.3
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• pp.384-392
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• 2007

The primary objective of this study was to determine the effects of a water-distilled extract with 15 kinds of Korean medicinal herb on antioxidant activity, antimicrobial activity against Helicobacter pylori, and lipid metabolism. The water-distilled extract (WE) and fermenting water-distilled extract (FE) of medicinal herbs were utilized in order to make functional beverages. The EDA (electron donating activity), SOD-like ability, and RAE (relative antioxidant efficacy) of WE averaged 24.47, 50.35, and 1.57%, respectively, but the EDA, SOD-like ability, and RAE of FE was retardeded by 12.01, 35.72, and 1.55%, respectively. The antimicrobial activity against Helicobacter pylori of WE averaged 12.84 mm as a diametric clear zone, and was significantly (p<0.05) higher than those measured in the WE and control. Serum triglyceride contents, total serum cholesterol contents, and serum LDL-cholesterol contents of the WE group were significantly (p<0.05) lower than those of the control group. The liver total-cholesterol contents and liver triglycerides of WE group were significantly (p<0.05) lower than those of the control group. The plasma TBARS value of the WE group was significantly (p<0.05) lower than that of the control group. The sensory evaluation, taste, and smell of FE were more desirable than those of WE, but the color of WE was more desirable. According to the above results, the water distilled extracts (WE) of 15 kinds of medicinal herb are supposed to be effective with regard to antioxidant activity and lipid metabolism, but the antimicrobial activity against Helicobacter pylori was increased as the result of fermentation.

• Korean Journal of Microbiology
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• v.44 no.4
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• pp.358-361
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• 2008

Effect of extract of fermented dropwort (Oenanthe stolonifera) on growth of intestinal harmful/useful bacteria and enzyme activity were investigated in vitro. The extract showed strong inhibition on harmful microbes including Vibrio and Salmonella, but mild inhibition on Bifidobacterium longum in both agar plate and liquid cultivation. Minimum inhibitory concentration (MIC) value of B. longum was the highest among tested microbes. Inhibition effect of fermented extract on harmful microbes increased according to fermentation period. Extract of fermented dropwort showed inhibitory effects on activity of microbial ${\beta}$-glucuronidase and tryptophanase. The inhibitory effects were also proportional to fermentation period. As consequence, it is assumed that the uptake of fermented dropwort might be useful for human intestinal health.

• Journal of Microbiology and Biotechnology
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• v.25 no.8
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• pp.1349-1360
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• 2015

The rhizospheric zone abutting plant roots usually clutches a wealth of microbes. In the recent past, enormous genetic resources have been excavated with potential applications in host plant interaction and ancillary aspects. Two Pseudomonas strains were isolated and identified through 16S rRNA and rpoD sequence analyses as P. fluorescens QAU67 and P. putida QAU90. Initial biochemical characterization and their root-colonizing traits indicated their potential role in plant growth promotion. Such aerobic systems, involved in gluconic acid production and phosphate solubilization, essentially require the pyrroloquinoline quinine (PQQ)-dependent glucose dehydrogenase (GDH) in the genome. The PCR screening and amplification of GDH and PQQ and subsequent induction of mutagenesis characterized their possible role as antioxidants as well as in growth promotion, as probed in vitro in lettuce and in vivo in rice, bean, and tomato plants. The results showed significant differences (p ≤ 0.05) in parameters of plant height, fresh weight, and dry weight, etc., deciphering a clear and in fact complementary role of GDH and PQQ in plant growth promotion. Our study not only provides direct evidence of the in vivo role of GDH and PQQ in host plants but also reveals their functional inadequacy in the event of mutation at either of these loci.

• Korean Journal of Environmental Agriculture
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• v.34 no.3
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• pp.244-251
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• 2015

BACKGROUND: Recent studies have described the importance of bacteria that can degrade polycyclic aromatic hydrocarbons (PAHs). Here we screened bacterial isolates from commercial gasoline for PAH degraders and characterized their ability to degrade PAHs, lipids and proteins as well as their enantioselective epoxide hydrolase activity, salt tolerance, and seawater survival. METHODS AND RESULTS: One hundred two bacteria isolates from commercial gasoline were screened for PAH degraders by adding selected PAHs on to the surface of agar plates by the sublimation method. A clear zone was found only around the colonies of PAH degraders, which accounted for 13 isolates. These were identified as belonging to Bacillus sp., Brevibacterium sp., Micrococcus sp., Corynebacterium sp., Arthrobacter sp., and Gordonia sp. based on 16S rRNA sequences. Six isolates belonging to Corynebacterium sp., 3 of Micrococcus sp., Arthrobacter sp. S49, and Gordonia sp. H37 were lipid degraders. Arthrobacter sp. S49 was the only isolate showing high proteolytic activity. Among the PAH-degrading bacteria, Arthrobacter sp. S49, Brevibacterium sp. S47, Corynebacterium sp. SK20, and Gordonia sp. H37 showed enantioselective epoxide hydrolase activity with biocatalytic resolution of racemic styrene oxide. Among these, highest enantioselective hydrolysis activity was seen in Gordonia sp. H37. An intrinsic resistance to kanamycin was observed in most of the isolates and Corynebacterium sp. SK20 showed resistance to additional antibiotics such as tetracycline, ampicillin, and penicillin. CONCLUSION: Of the 13 PAH-degraders isolated from commercial gasoline, Arthrobacter sp. S49 showed the highest lipid and protein degrading activity along with high active epoxide hydrolase activity, which was the highest in Gordonia sp. H37. Our results suggest that bacteria from commercial gasoline may have the potential to degrade PAHs, lipids, and proteins, and may possess enantioselective epoxide hydrolase activity, high salt tolerance, and growth potential in seawater.

• Journal of Welding and Joining
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• v.1 no.2
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• pp.45-52
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• 1983

Many pressure vessels for the hot H$\sub$2//H$\sub$2/S service are made of 2+1/4Cr-1Mo steel with austenitic stainless steel overlay to combat agressive corrosion due to hydrogen sulfide. Hydrogen dissolves in to materials during operation, and sometimes gives rise to unfore-seeable damages. Appropriate precautions must, therefore, be taken to avoid the hydrogen induced damages in the design, fabrication and operation stage of such reactor vessels. Recently, hydrogeninduced cracking (or Disbonding) was found at the interface between base metal and stainless weld overlay of a desulfurizing reactor. Since the stainless steel overlay weld metal is subjected to thermal and internal-pressure loads in reactor operation, it is desirable for the overlay weld metal to have high strength and ductility from the stand point of structural safety. In section III of ASME Boiler and Pressure Vessel Code, Post-Weld Heat Treatment(PWHT) of more than one hour per inch at over 1100.deg. F(593.deg. C) is required for the weld joints of low alloy pressure vessel steels. This heat treatment to relieve stresses in the welded joint during construction of the pressure vessel is considered to cause sensitization of the overlay weld metal. The present study was carried out to make clear the diffusion of carbon migration by PWHT in dissimilar metal welded joint. The main conclusion reached from this study are as follows: 1) The theoretical analysis for diffusion of carbon in stainless steel overlay weld metal does not agree with Fick's 2nd law but the general law of molecular diffusion phenomenon by thermodynamic chemical potential. 2) In the stainless steel overlay welded joint, the PWHT at 720.deg. C for 10 hours causes a diffusion of carbon atoms from ferritic steel into austenitic steel according to the theoretical analysis for carbon migration and its experiment. 3) In case of PWHT at 720.deg. C for 10 hours, the micro-hardness of stainless steel weld metal in bonded zone increase very highly in the carburized layer with remarkable hardening than that of weld metal.

• Journal of Life Science
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• v.23 no.2
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• pp.242-248
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• 2013

The objective of this study was to develop a mineral phosphate-solubilizing bacterium as a biofertilizer. A mineral phosphate-solubilizing bacterium HR-1019 was isolated from cultivated soils. It was identified as Bacillus subtilis by 16S rDNA analysis. The phosphate-solubilizing activities of the HR-1019 strain against three types of insoluble phosphate, hydroxyapatite, tri-calcium phosphate, and aluminum phosphate were quantitatively determined. When 5% of glucose concentration was used as a carbon source, the strain showed marked mineral phosphate-solubilizing activity. Mineral phosphate solubilization was directly related to pH drop in the culture solution of the strain. The pathogenic activity and antifungal effects of the HR-1019 strain were measured inclear zones formed in PDA media.

• 한국신재생에너지학회:학술대회논문집
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• 2006.06a
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• pp.407-409
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• 2006

Geochemical analyses carried out on samples collected from cores on and near the southern smit of Hydrate Ridge have advanced understanding by providing a clear contrast of the two major modes of marine gas hydrate occurrence. High concentrations (15%-40% of pore space) of gas hydrate occurring at shallow depths (0-40 mbsf) on and near the southern summit are fed by gas migrating from depths of as much as 2km within the accretionary prism. This gas carries a characteristic minor component of C2-C5 thermogenic hydrocarbons that enable tracing of migration pathways and may stabilize the occurrence of some structure II gas hydrate. A structure II wet gas hydrate that is stable to greater depths and temperatures than structure I methane hydrate may account for the deeper, faint second bottom simulating reflection (BSR2) that occurs on the seaward side of the ridge. The wet gas is migrating In an ash/turbidite layer that intersects the base of gas hydrate stability on the seaward side of and directly beneath the southern summit of Hydrate Ridge. The high gas saturation (>65%) of the pore space within this layer could create a two-phase (gas + solid) system that would enable free gas to move vertically upward through the gas hydrate stability zone. Away from the summit of the ridge there is no apparent influx of the gas seeping from depth and sediments are characterized by the normal sequence of early diagenetic processes involving anaerobic oxidation of sedimentary organic matter, initially linked to the reduction of sulfate and later continued by means of carbonate reduction leading to the formation of microbial methane.

• 한국해양학회지
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• v.26 no.3
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• pp.242-254
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• 1991

Southern sea of Korea was investigated for primary productivity during four scientific cruises of Korea Ocean research and Development Institute. Frontal structure appeared to be an important physical characteristic in enhancing the phytoplankton production in the study area. Relatively high productivity was occurred near the front between Tsushima Warm Current Water and Coastal Waters of China continent in March 1990 and in November 1989, and near the front between Tsushima Warm Current Water and Korean coastal Water in April 1989. In August 1988 high productive zone was limited to the tidal front off the southwestern coast of Korea. Nutrient supply related to the frontal structure might play a dominant role in increasing the primary productivity but mechanisms of nutrient enrichment are not clear. Average column productivity showed its maximum in April 1989 (1727 mgC/m$^2$/day). In the costal Waters of the china Continent incident light may be an important factor in regulating the regulating the phytoplankton production because of low light penetration rate resulting from high turbidity.

• Current Research on Agriculture and Life Sciences
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• v.31 no.3
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• pp.170-176
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• 2013

In this study, we selected some material to have potential bioactivity from natural plants, confirmed as basic data for industrializing and tried to develope the food materials using them. DPPH, ABTS, antioxidant protection factor, TBARs and antimicrobial activity of extracts from Rosa multiflora Thunberg fruits were determined. The total phenolics extracted from Rosa multiflora were 12.08, 11.82, 11.1 and 12.6 mg/g when using water, 70% ethanol, 70% methanol and 70% acetone as the solvent, respectively. The optimum conditions for extracting the phenolic compounds were 70% ethanol over for 12 hrs(11.82 mg/g). The electron donating ability and inhibition rate on ABTS of the 70% ethanol extracts were 97% and 92.2%, respectively while the antioxidant protection factor(PF) of the water extracts and 70% ethanol extracts were 1.79 and 1.34 PF, respectively. The TBAR (thiobarbituric acid reactive substance) value were $1.3{\mu}M$ for the control and $0.15{\mu}M$ for the 70% ethanol extracts. The inhibitory activity against ${\alpha}$-amylase was 26% for the 70% ethanol extracts. The 70% ethanol extracts from Rosa multiflora Thunberg fruits exhibited antimicrobial activity against H. pylori, S. epidermidis, S. aureusand and E. coli with clear zone diameters of 14, 25, 14 and 13 mm, respectively when using $200{\mu}g/mL$ of the phenolic compounds. An HPLC analysis identified 6 major phenolic metabolites in the Rosa multiflora Thunberg fruits extracts: rosmarinic acid, caffeic acid, chlorogenic acid, courmaric acid, protocatechuic acid and quercetin. In particular, the content of rosmarinic acid was the highest in the 70% ethanol extracts. Therefore these results indicate that 70% ethanol extracts from Rosa multiflora Thunberg fruits can be useful as a natural antioxidant and in functional foods.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.31 no.4
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• pp.529-534
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• 1998

Age and growth of the yellow goosefish, Lophius litulon, were studied using samples collected from the southwestern waters of Korea. Vertebrae of the fish had relatively clear annuli on their surface. The opaque zone of vertebrae was formed once a year between March and April. The oldest fish observed in this study was 8 years old for females and 5 years old for males. The relationship between the radius (R) of vertebral centrum and total length (L) was as follows: L=12.7+4.8R for females and L=9.8+5.6R for males. The relationship between total length and body weight (W) was as follows : $W=0.0089L^{3.0311}$ for females and $W=0.0329L^{2.7752}$ for males. Growth in length of the fish was expressed by the von Bertalanffy's equation as $L_t=127.60(1-e^{-0.1228(t+0.3851)})$ for females and $L_t=82.23(1-e^{-0.1832(t+0.6431)})$ for males.