• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2000년도 춘계학술발표대회
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• pp.89-91
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• 2000

Polynuclear aromatic hydrocarbon (PAH) compounds are highly carcinogenic chemicals and common groundwater contaminants that are observed to persist in soils. The adherence and slow release of PAHs in soil is an obstacle to remediation and complicates the assessment of cleanup standards and risks. Biological degradation of PAHs in soil has been an area of active research because biological treatment may be less costly than conventional pumping technologies or excavation and thermal treatment. Biological degradation also offers the advantage to transform PAHs into non-toxic products such as biomass and carbon dioxide. Ample evidence exists for aerobic biodegradation of PAHs and many bacteria capable of degrading PAHs have been isolated and characterized. However, the microbial degradation of PAHs in sediments is impaired due to the anaerobic conditions that result from the typically high oxygen demand of the organic material present in the soil, the low solubility of oxygen in water, and the slow mass transfer of oxygen from overlying water to the soil environment. For these reasons, anaerobic microbial degradation technologies could help alleviate sediment PAH contamination and offer significant advantages for cost-efficient in-situ treatment. But very little is known about the potential for anaerobic degradation of PAHs in field soils. The objectives of this research were to assess: (1) the potential for biodegradation of PAH in field aged soils under denitrification conditions, (2) to assess the potential for biodegradation of naphthalene in soil microcosms under denitrifying conditions, and (3) to assess for the existence of microorganisms in field sediments capable of degrading naphthalene via denitrification. Two kinds of soils were used in this research: Harbor Point sediment (HPS-2) and Milwaukee Harbor sediment (MHS). Results presented in this seminar indicate possible degradation of PAHs in soil under denitrifying conditions. During the two months of anaerobic degradation, total PAH removal was modest probably due to both the low availability of the PAHs and competition with other more easily degradable sources of carbon in the sediments. For both Harbor Point sediment (HPS-2) and Milwaukee Harbor sediment (MHS), PAH reduction was confined to 3- and 4-ring PAHs. Comparing PAH reductions during two months of aerobic and anaerobic biotreatment of MHS, it was found that extent of PAHreduction for anaerobic treatment was compatible with that for aerobic treatment. Interestingly, removal of PAHs from sediment particle classes (by size and density) followed similar trends for aerobic and anaerobic treatment of MHS. The majority of the PAHs removed during biotreatment came from the clay/silt fraction. In an earlier study it was shown that PAHs associated with the clay/silt fraction in MHS were more available than PAHs associated with coal-derived fraction. Therefore, although total PAH reductions were small, the removal of PAHs from the more easily available sediment fraction (clay/silt) may result in a significant environmental benefit owing to a reduction in total PAH bioavailability. By using naphthalene as a model PAH compound, biodegradation of naphthalene under denitrifying condition was assessed in microcosms containing MHS. Naphthalene spiked into MHS was degraded below detection limit within 20 days with the accompanying reduction of nitrate. With repeated addition of naphthalene and nitrate, naphthalene degradation under nitrate reducing conditions was stable over one month. Nitrite, one of the intermediates of denitrification was detected during the incubation. Also the denitrification activity of the enrichment culture from MHS slurries was verified by monitoring the production of nitrogen gas in solid fluorescence denitrification medium. Microorganisms capable of degrading naphthalene via denitrification were isolated from this enrichment culture.

• Research in Plant Disease
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• 제8권3호
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• pp.184-188
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• 2002

An antagonistic bacteria, Bacillus licheniformis Nl strain which effectively inhibited mycelial growth of gray mold rot pathogen, Botrytis cinerea was isolated from the rhizosphere of perilla crop. Powder soy formulation by B. lichentfomis Nl strain as a biocontrol agent was developed far the first time and estimated its control effect on perilla leaves in this study. First of all, far the mass production of antifungal metabolites of B. lichentfomis Nl strain in flask liquid culture, the most effective carbon and nitrogen source were selected as glucose and tryp-tone, respectively, For the formulation, vegetative biomass of B. licheniformis Nl strain from 5-day-old liquid culture in nutrient broth added glucose and tryptone was mixed with soy flour, rice flour glucose, FeSo$_4$~7$H_2O$, and MnCl$_2$. 4$H_2O$, and dried and pulverized. In plastic house test, powder soy formulation effectually controlled gray mold rot as the control value of 93.1 %, was more effective than chemical fungicide, benomyl showing the control value of 86.1%. Thus, development of powder soy formulation of B. lichentfomis Nl will aid large-scale application of biological control in field trials.

• Journal of Life Science
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• 제26권11호
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• pp.1330-1335
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• 2016

Sasa species leaves have been used in traditional medicine for their anti-inflammatory, antipyretic, and diuretic properties. Sasa quelpaertensis Nakai is a small bamboo grass that grows only on Mt. Halla on Jeju Island, Republic of Korea. This small bamboo grass has recently been the focus of much attention due to its potential biomass as well as its beneficial health effects. In this study, to promote the efficient utilization of the S. quelpaertensis leaf, we established a simple preparation method for phytochemical-rich extract (PRE) by comparing phytochemical contents and biological activities according to extraction methods. high performance liquid chromatography (HPLC) analysis revealed that the contents of two major phytochemicals such as, tricin (5.35 mg/g) and p-coumaric acid (44.10 mg/g) contained in PRE were higher than those in fresh hot water extract (SQH, p-coumaric 23.39 mg/g, tricin 0.18 mg/g) and ethanol extract (SQE, p-coumaric 10.8 mg/g, tricin 0.38 mg/g). The antioxidant activities [1,1-diphenyl-2-picrylhydrazy (DPPH) radical scavenging activity, 2,2'-azino-bis-3-ethylbenzothiazoline-6-sulphonic acid (ABTS) radical scavenging activity, nitric oxide (NO) scavenging activity, and xanthine oxidase inhibitory activity] of PRE were higher than those of SQH and SQE. PRE effectively inhibited NO production in LSP- stimulation RAW 264.7 cells, and the growth of human promyelocytic leukemia (HL-60) cells. These results suggest that PRE has a potential as a promising antioxidant and anti-inflammatory agent.

• Korean Journal of Food Science and Technology
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• 제15권1호
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• pp.56-61
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• 1983

Direct production of biomass from starch using amylolytic yeast, Sporobolomyces holsaticus FRI Y-5 was studied with varying the ratios between carbon and other nutrient sources in the medium. It was investigated under condition of constant C/P and C/S ratio to influence the initial concentration of starch $(S_o)$ and C/N ratio on its growth which is described as the specific growth rate $({\mu})$, cell yield (Y), the maximum concentration of cell $(X_m)$, and productivity (P). They were very dependent on both $S_o$ and C/N ratio. The form of the relationship between and ${\mu}$ and $S_o$ was observed to be similar to saturation kinetics at C/N = 100 but presented substrate inhibition at other C/N ratios. As $S_o$ was changed from 22.5 to 90 g/l, Y was observed to vary with C/N ratios but seemed to decrease as a wholes. $X_m$ was linearly related to $S_o$ at more than C/N = 50 but at less than C/N = 10 substrate inhibition was presented. P increased suddenly to $S_o$ = 45 g/l and then changed decreasingly at less than C/N = 50, but at more than C/N = 100 it changed increasingly. The effect of C/P ratio and C/S ratio on the yeast growth was also investigated at constant $S_o$ and C/N ratio. ${\mu}$ was dependent on C/P and C/S ratios, but Y, independent on them. But $X_m$ was reliant upon C/P ratio but not upon C/S ratio.

• KOREAN JOURNAL OF CROP SCIENCE
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• 제41권6호
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• pp.640-649
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• 1996

This study was conducted to obtain fundamental informations necessary to breed forage sorghum at the field of the Livestock Experiment Station from 1988 to 1991. Heterosis was discussed in crossing groups of sorghum X sweet sorghum, sorghum X sudangrass, and (sorghum X sweet sorghum) X sudangrass. Leaf dry weight and stalk dry weight per plant in sweet sorghum crossing group, stalk dry weight per plant in sorghum X sudangrass crosses and leaf area per plant in three way crosses showed the greatest Heterobeltiosis(H$_{b}$). There were significant differences in plant height, stalk diameter and number of tillers per plant between sweet sorghum and sudangrass crosses. H$_{b}$ for total dry matter yield in sweet sorghum and sudangrass crosses were 45.9% and 95.0%, respectively. On the other hand, heterosis for total dry matter yield in three way crosses was smaller than H$_{b}$. There was no relationship between dry matter yield of parents and heterosis of hybrids in sweetsorghum crosses. However, positive correlations between parental yield and hybrid yields were observed. In sudangrass crosses, there were negative correlations between parental yields and heterosis of hybrids. However, no correlation between parental yields and hybrid yields were observed. In three way crosses, there were no correlations between parental yields and heterosis, and between parental yields and hybrids yields.

• Journal of Plant Biotechnology
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• 제42권2호
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• pp.88-92
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• 2015

Cassava (Manihot esculenta Crantz) is a useful root crop for food, animal feed and various industrial materials including biofuel. Despite of its importance as an industrial crop, the genetic engineering approaches to manipulate transgenic plant development in cassava are limited. In this study, to develop new cultivar with high level of carotenoids and enhanced tolerance to environmental stresses, sweetpotato IbOr gene involved in accumulation of carotenoids was introduced into an Indonesian IDB high-yielding cassava cultivar under the control of oxidative stress-inducible SWPA2 promoter through Agrobacterium-mediated transformation of friable embryogenic calli. The 19 transgenic lines were successfully generated on the basis of gDNA-PCR and IbOr transcript levels for further characterization in terms of carotenoid contents and environmental stresses. Therefore, IbOr transgenic cassava plants may be developed for enhanced biomass production with high levels of carotenoids on marginal lands.

• Journal of Plant Biotechnology
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• 제34권3호
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• pp.263-269
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• 2007

To establish a optimum culture condition in vitro for production of seedlings in Wasabia japonica, the effects of salt strength, sucrose concentration, and $NH_4/NO_3$ ratio on the shoot growth in MS medium were investigated. The full strength of MS medium was the best condition for shoot growth, and in $1/4{\sim}1/2x$ or 2x MS medium the growth was significantly suppressed. Growth of shoots was enhanced when sucrose was added in MS medium after 2 weeks of culture, and the best result was found at 3% sucrose addition. ${NH_4}^+/{NO_3}^-$ ratio of 10:50 gave the highest biomass of shoot in the liquid culture with MS medium, and increasing the ${NH_4}^+$ ratio in the medium significantly reduced the growth of shoot.

• Journal of Korean Society of Water and Wastewater
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• 제24권2호
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• pp.195-202
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• 2010

The evaluation of organic matters and nutrients removal was investigated for the synthetic wastewater and the high strength of dairy wastewater. Two different systems were performed for this research. System A composing of a single RBC with tapered aeration was fed with the synthetic wastewater for 74 days with 173L/day of influent, 200% of internal return and 100% of sludge return for the period 1 and 2. The feed conditions were maintained 346L/day of influent, 50% of internal return and sludge return for the period 3. The dairy wastewater was introduced to evaluate treatment efficiency for system B composing of dual RBCs and tapered aeration tanks for 50 days of experimental run time, in which hydraulic rates were maintained at the constant ratios of 346L/day, 50% of internal return and 50% of sludge return. The spiral string media made of nylon fibre was attached by Bacillus sp. in RBC for both systems. The specific area of string media was $1.4m^2$/m and biomass was maintained at the concentrations of 23g/m. The synthetic wastewater was supplied by 1,800mg/L of glucose, 500mg/L of $NH_4Cl$, and 500mg/L of $KH_2PO_4$ to system A. The dairy wastewater was supplied to system B from dairy production plant. The average influent concentrations were 1,334mg/L of BOD, 2,014mg/L of CODcr, 160mg/L of T-N, and 12mg/L of T-P in system A. The average influent concentrations of parameters were 1,006 mg/L for BOD, 1,875mg/L for $COD_{cr}$, 51.6mg/L for T-N and 8.9mg/L for T-P in system B. Results indicated that removal efficiencies of BOD and $COD_{cr}$ were more than 90% however, the removal efficiency of T-N was 87%, and that of T-P was 82% for system A. Removal efficiencies were 98.5% of BOD, 91.3% of nitrogen and 89% of phosphorus for system B. The removal efficiencies of organic matters, T-N and T-P were higher in system B than in system A. The effluent quality issued by the stringent national legislations for the discharge of the high strength of dairy products wastewater can be improved using sequential RBCsand tapered aeration reactors rather than a single RBC and tapered aeration reactors with Bacillus sp.

• Journal of the Korean Wood Science and Technology
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• 제45권3호
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• pp.317-326
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• 2017

The wood and bark of Hawthorn tree (Crataegus pinnatifida Bunge) were immersed with 70% aqueous acetone for 3 days. After filtering, the wood extracts were fractionated with n-hexane, chloroform ($CHCl_3$), n-butanol (n-BuOH) and $H_2O$, and the bark extracts were fractionated with n-hexane, $CHCl_3$, ethylacetate (EtOAc) and $H_2O$. Then antioxidative and anti-inflammatory activities were evaluated on each fraction. Antioxidative activity indicated high activity in the n-butanol soluble fraction of wood and in the EtOAc soluble fraction of bark. Especially, the EtOAc soluble fraction of bark showed much higher antioxidative value compared to the controls, buthylated hydroxytoluene (BHT) and ${\alpha}$-tocopherol. In the anti-inflammatory activity, all of the tested fractions except the $H_2O$ soluble fraction of wood showed high inhibitory effect on nitric oxide (NO) production. Based on the above results, the extracts of hawthorn tree may be applied for one of the natural biomass sources that can be used as an antioxidant and an anti-inflammatory substance.

• Journal of the Korean Wood Science and Technology
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• 제45권3호
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• pp.250-257
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• 2017

Eight hydrolyzable tannin compounds, such as gallic acid (1), methyl gallate (2), kurigalin (3), 1,2,3,6-tetra-O-galloyl-${\beta}$-D-(+)-glucose (4), 1,2,3,4,6-penta-O-galloyl-${\beta}$-D-(+)-glucose (5), 6-m-digalloyl-1,2,3,4,6-penta-O-galloyl-${\beta}$-D-(+)-glucose (6), isocorilagin (7), macabarterin (8), were isolated from the EtOAc and $H_2O$ soluble fractions of Katsura tree (Cercidiphyllum japonicum) leaves, wood and bark. Then antioxidative and anti-inflammatory activity were evaluated on the each isolated compound. The antioxidative test was DPPH radical scavenging activity and all of the isolated compounds indicated much higher antioxidative values compare to the controls, BHT and ${\alpha}$-tocopherol. In the anti-inflammatory test measuring nitric oxide (NO) inhibition activity, methyl gallate, 1,2,3,6-tetra-O-galloyl-${\beta}$-D-glucose and 1,2,3,4,6-penta-O-galloyl-${\beta}$-D-glucose inhibited NO production, and especially, methyl gallate showed high inhibition activity. However, the anti-inflammatory activity of the hydrolyzable tannins did not show positive effect. Based on the above results, the hydrolyzable tannins of katsura tree may be used as one of the natural biomass sources that can substitute with the synthetic antioxidant.