• Journal of Life Science
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• v.25 no.1
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• pp.68-74
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• 2015

Recently developed black waxy rice with a giant embryo ('Nunkeunheukchal', BGE) was selected and processed to produce high quality nutritional food. BGE contains high levels of several phytochemicals with antioxidant activities, as well as other reported health beneficial properties. In addition, the giant embryo has high protein, lipid, and amino acids contents. Within the free amino acids, ${\gamma}$-aminobutyric acid (GABA), a major inhibitory neurotransmitter, has long been used for treating the aftereffects of brain injuries and stroke. A method for manufacturing pop-rice and black rice tea by popping process in BGE is provided to increase a taste, nutrition and functionality. The produced 'pop-rice' showed increased protein (11.3%) and lipid (3.7%) contents compared with control variety, IB ('Ilmibyeo'). In addition, melanoidin related products, polyphenol and functional amino acid contents were increased by the popping process. Pop-rice tea made of BGE showed the highest extraction of total sugar, glucose, raffinose and sucrose (4 times higher than brown rice) by hot water. Scavenging activity ($SC_{50}$) of processed BGE rice powder showed strong antioxidative activity of 0.24 mg/ml using DPPH and 1.82 mg/ml using ABTs method. Thereafter, these results suggested that the popping processed rice of BGE could be one of the promising materials for healthy food development.

• Journal of Life Science
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• v.18 no.12
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• pp.1718-1721
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• 2008

The skin of human is constantly being exposed to environmental irritants such as ultraviolet, smoke and chemicals. These irritants cause free radicals and reactive oxygen species which leave serious damages on the cells of skin. The water and ethanol extracts of Cambodian Phellinus linteus were investigated for the activities of anti-lipid peroxidation and anti-wrinkle effects to apply as a functional ingredient for cosmetic products. As the result of evaluation of liquid oxidation rate by add $Fe^{2+}$ and $Cu^{2+}$ to Cambodian Phellinus linteus extracts, Cambodian Phellinus linteus ethanol extracts were higher than Cambodian Phellinus linteus water extracts in the chealting ability of $Fe^{2+}$ and $Cu^{2+}$. The Cambodian Phellinus linteus ethanol extracts exhibited that anti-lipid peroxidation higher than butylated hydroxytoluene (BHT) at the concentration of 0.1 mg/ml, 0.5 mg/ml and 1 mg/ml. Cambodian Phellinus linteus water and ethanol extracts showed a higher inhibitory effect on $Fe^{2+}$-induced lipid peroxidation compared to $Cu^{2+}$-induced lipid peroxidation. In the case of anti-wrinkle effect, the elastase inhibition activity of Cambodian Phellinus linteus ethanol extracts was 50.7%, and it is higher than urosolic acid at the concentration of 0.01 mg/ml. Also, in collagenase inhibition activity, Cambodian Phellinus linteus water extract showed low effect, but Cambodian Phellinus linteus ethanol extract was about 50% at a 0.1 mg/ml. concentration. These results proved that Cambodian Phellinus linteus had anti-lipid peroxidation and anti-wrinkle effect. Therefore, Cambodian Phellinus linteus could be useful as an anti-wrinkle cosmetic ingredient.

• Korean Journal of Ecology and Environment
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• v.38 no.2 s.112
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• pp.196-206
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• 2005

The fish community in the mid-upper region of Gam Stream was examined seasonally from 2001 to 2003 in order to perform an environmental impact assessment prior to a construction of Gamcheon Multipurpose Dam. Additional investigation was conducted in August 2004 to confirm the fish fauna reported and to examine the ecological characteristics of Zacco temminckii population. The total number of fish caught from the study sites was 1,081 fish representing 5 families 14 species. There were 6 Korean endemic species including Coreoleuciscus splendidus, Squalidus gracilis majimae, Microphysogobio yaluensis, Liobagrus mediadiposalis, Coreoperca herzi and Odontobutis platycephala, but no endangered or vulnerable species were found. Length-weight relation, condition factor (K) and relative condition factor (Kn) of Zacco temminckii were compared by the study sites and stream. The equations based on length-weight relation in Buhang and Gam Streams were TW\;=\;0.000004TL^{3.2357}$ and TW\;=\;0.000002TL^{3.3566}$, respectively indicating the fish in Gam Stream became more rotund as length increases. The condition factor (K) and relative condition factor (Kn) against total length of Zacco temminckii at two streams indicated that the fish (>70 mm) in Cam Stream (mean K and Kn= 1.116, 1.21 respectively) had better nutritional condition than those in Buhang Stream (mean K and Ln = 1.046, 1.14 respectively). The results were corresponded with natural disturbances such as drought and intensive rainfall from 2001 to 2003 followed by human activities such as stream repair works. Therefore, it is considered to perform environmental impact assessment with not only confirmation of fish composition but also examination of ecological characteristics in population- level.

• Korean Journal of Agricultural and Forest Meteorology
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• v.9 no.1
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• pp.1-16
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• 2007

The use of information on natural resources is indispensable to most agricultural activities to avoid disasters, to improve input efficiency, and to increase lam income. Most information is prepared and managed at a spatial scale called the "Hydrologic Unit" (HU), which means watershed or small river basin, because virtually every environmental problem can be handled best within a single HU. South Korea consists of 840 such watersheds and, while other watershed-specific information is routinely managed by government organizations, there are none responsible for agricultural weather and climate. A joint research team of Kyung Hee University and the Agriculture, forestry and Fisheries Information Service has begun a 4-year project funded by the Ministry of Agriculture and forestry to establish a watershed-specific agricultural weather information service based on "high definition" digital climate maps (HD-DCMs) utilizing the state of the art geospatial climatological technology. For example, a daily minimum temperature model simulating the thermodynamic nature of cold air with the aid of raster GIS and microwave temperature profiling will quantify effects of cold air drainage on local temperature. By using these techniques and 30-year (1971-2000) synoptic observations, gridded climate data including temperature, solar irradiance, and precipitation will be prepared for each watershed at a 30m spacing. Together with the climatological normals, there will be 3-hourly near-real time meterological mapping using the Korea Meteorological Administration's digital forecasting products which are prepared at a 5 km by 5 km resolution. Resulting HD-DCM database and operational technology will be transferred to local governments, and they will be responsible for routine operations and applications in their region. This paper describes the project in detail and demonstrates some of the interim results.

• Research in Plant Disease
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• v.23 no.2
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• pp.159-167
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• 2017

This study was conducted to evaluate the control efficacy of the organic farming materials on cucumber scab caused by Cladosporium cucumerinum PT1 (KACC 48094). The antifungal activities in vitro as well as the suppressive effect of 43 organic farming materials on the spore germination and germ tube growth by inoculating spore suspension on cucumber seedlings in vivo were investigated. Thirteen organic farming materials inhibited the mycelial growth of C. cucumerinum and nine of these were microbial agents. In the screening using cucumber seedlings, six organic farming materials were very effective with control efficacy value of 90%. Among them, Bacillus amyloliquefaciens M27 provided suppressive effect on both mycelial growth and spore germination against cucumber scab. Finally, nine organic farming materials were selected to test the protective and curative effects, and all chosen organic farming materials significantly suppressed disease incidence when applied in the preventive action, in comparison with the curative action. Especially, Bordeaux mixture I and III gave excellent protective control efficacy with control values of 96.7% and 73.3%, respectively, whereas its curative control effect was significant low. Among these, only Thymus quinquecostatus+Sophora extract showed curative activity, although the control value was as low as 50%. This study suggests that cucumber scab can be controlled by some organic farming materials in the farmhouses under comparatively cold and wet condition and protective treatment is more important and efficient.

• Korean Journal of Soil Science and Fertilizer
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• v.20 no.3
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• pp.261-268
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• 1987

A green house experiment was conducted to find out the differences in the amount of biologically fixed nitrogen and kjeldahl nitrogen on the different soil texture, kinds and amounts of fertilizer nitrogen under light (photosynthetic $N_2$-fixation) and dark (heterotrophic $N_2$-fixation) condition in submerged paddy soil. The reults obtained were summarized as follows; 1. The amount of biologically fixed nitrogen per mg carbon from different organic matter was obtained as 0.13 mg in glucose, 0.09 mg in rice straw, and 0.07 mg in refused mushroom compost and barley straw under 60 days of incubation. 2. Nitrogen fixing activities were decreased with increase of fertilizer nitrogen and those tendency was pronounced more in sandy soil with application of urea than that of ammonium sulfate. 3. The application of ammonium sulfate in sandy soil under light condition was increased the photosynthetic $N_2$-fixation and the applied urea was remarkably reduced the heterotrophic $N_2$-fixation in sandy soil. The proportion of biologically fixed total nitrogen after experiment in sandy soil was obtained as 25% for dark(heterotrophic $N_2$-fixation) and 75% for light (photosynthetic $N_2$-fixation) condition. On the other hand, very similar biological $N_2$-fixing tendency was obtained between kinds of nitrogen fertilizer and two light condition in clayey soil. 4. The kjeldahl nitrogen was remarkably decreased after experiment under dark condition with application of urea than that of light condition with ammonium sulfate, and no remarkable decreasing tendency was obtained in clayey soil between two kinds of fertilizer nitrogen. 5. The high significant positive correlationship was obtained between calculated biological nitrogen fixation by acetylene reducing activity and kjeldahl nitrogen after experiment under light (y=0.8488X-5.9632, $r=0.9928^{**}$, n=21) and dark (y=0.8795X-7.1056, $r=0.9782^{**}$, n=21) condition. In this experiment condition, conversion factors of 6:1 was obtained from biological nitrogen fixation to soil nitrogen.

• Journal of the Korean Wood Science and Technology
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• v.38 no.6
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• pp.547-560
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• 2010

The optimum culture condition of Schizophyllum commune for the cellulase production and its enzymatic characteristics for saccharification of cellulosic biomass were analyzed. S. commune secrets ${\beta}$-1,4-xylosidase (BXL) and cellulases, including endo-${\beta}$-1,4-glucanase (EG), cellobiohydrolase (CBH), and ${\beta}$-glucosidase (BGL). The optimum reaction temperature for all cellulases was $50^{\circ}C$ and the thermostable range was $30{\sim}40^{\circ}C$C. The optimum reaction pH for all cellulases was 5.5 in a range of temperature from $0^{\circ}C$ to $55^{\circ}C$. The best nutritions for the cellulase production of S. commune among tested nutrients were 2% cellulose for the carbon source and corn steep liquor or peptone/yeast extract for the nitrogen source without vitamins. The environmental culture condition for the cellulase production was 5.5~6.0 for pH at $25{\sim}30^{\circ}C$. The enzyme activities of EG, BGL, CBH, and BXL were 3670.5, 631.9, 398.5, and 15.2 U/$m{\ell}$, respectively, after concentration forty times from the culture broth of S. commune which was grown at the optimized culture condition. Alternative filter paper unit assay showed 11 FPU/$m{\ell}$ enzyme activity. The saccharification tests using cellulase of S. commune showed the low saccharification rate on tested hardwoods but a high value of 50.5% on cellulose, respectively. The saccharification rate (50.5%) of cellulose by cellulase produced in this work is higher than 45.7% in the commercial enzyme (Celluclast 1.5L, 30 FPU/g, glucan).

• 한국해양학회지
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• v.14 no.1
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• pp.15-25
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• 1979

A study on field bioassay test using four species of commercially important shellfish was carried out to assess the effect of pollutants and determine the extent of marine environmental pollution of the Masan Bay from 9 to 15 August 1978. Water quality analysis and planktological examination of sea water were made during the experiment and the examination gave the following results. The water temperature was so high at 31.7$^{\circ}C$ in maximum and rather subject to change on weather condition of the land than on the effect of the water mass from outer bay. The range of DO,COD and SS at the stations were 0.3-7.08cc/l, 0.07-3.31ppm and 5.5-117ppm, respectively with the high values of COD and SS at the stations 7 and 1. The concentrations of the dissolved inorganic nitrogen in sea water, NH$\sub$4/-N, NO$\sub$2/-N, NO$\sub$3/-N, and PO$\sub$4/-P were 18.90-99.80, 2.48- 19.60, 13.00-39.00 and 1.04-14.0$\mu\textrm{g}$ at/l, respectively with decrease of their values in the outer part of the Bay. The high values mentioned above were caused by the sewage and industrial activities. The effects of organic waste are increased oxygen demand, nutrient concentration, turbidity and a higher input of pathogens, leading to structural changes in the marine ecosystems and to a considerable hazard to public health. The percentage composition of phytoplankton standing crop between diatom and dinoflagellate was characterized by making a difference between the two groups in respect of location: a decrease of diatom and a increase of dinoflagellate in numerical abundance toward inner part from outer part of the bay. Namely phytoplankton organisms were composed of 80% of diatom and 20% of dinoflagellate in outer bay, on the contrary, only 4% of diatom and 96% of dinoflagellate occupied by 94% of prorocentrum micans known as tolerant species to polluted reaas in the inner bay. On the occurrence and composition of zooplankton, there are two significant communities in the bay:one is characterized by the predominance of Oithona nana and the other by Favella sp They were composed of a range from 84% to 90% of the total organisms and monotonously constituted of themselves only at most inner station 3 even small numbers. From the results mentioned above, Oithona nana, Favella and prorocentrum micans recommed themselves as valuable indicators for judging the extent of the marine pollution.During the period of the biossays Mytilus edulis showed the highest mortality and Tapes japonica the lowest one between the four test species. The highest death rate by stations was found at most inner stations 3'and 4near Masan Free Export Zone with the most sensitive response and the lowest one occured at outer station 13 where no death specimen of oyster and arkshell was found during the whole test period.As for mussel,85 percent death rate appeared after 72 hours and 100percent rate after 120hours at station 4. It was found that the significant high mortality of the test shellfish mentioned above was caused by severe pollution with mainly organic pollutants from domestic sewage and industrial wastes from the results of too much higher concentrations of dissolved inorganic nitrogen especially ammonia-N,COD,SS and lack of dissolved oxygen,and furthermore occurrence and abundance composition of Prorcentrum,Favella and Oithona nana by stations, valuable indicator species of coastal pollution by orgnic and boilogical pollutants.

• The Korean Journal of Mycology
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• v.20 no.4
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• pp.337-346
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• 1992

Trichoderma spp. are an effective control agent for damping-off or other plant diseases. The interaction between. T. hamatum and Rhizoctonia solani on the rhizosphere or surface soil were examined to assess the possible roles of antibiosis or competition in the mechanisms of biological control agents as a basic research. In a proportional comparison, total bacteria, fungi, actinomycetes and Trichoderma spp were 65%, 8.8%, 25.9% and 0.28% respectively in their distribution in the soil. Among Trichoderma spp isolated, the 5 species of Trichoderma spp were indentified as T. koninggii, T. pseudokoninggii, T. aureoviridi, T. hamatum and T. viride respectively. In a mycoparasitic test, one isolate of T. hamatum strain Tr-5 showed an enzymatic ability to break fungal hyphae into piecies and infected on the R. solani hyphae showing a parasitism. Spore germination of the all isolates of Trichoderma spp showed a 1.7-7.3% of germination in natural soil conditions, but the percentage was high in sterile soil indicating all the natural soil were fungistatic on conidia of Trichoderma spp. In rhizosphere competent assay in pea plant, the antagonistic T. hamatum, T. viride, T. koninggii, T. pseudokoninggii showed a colonizing upper soil depth in rhizosphere around 1-3 cm in root zone, but the colonizing ability was much reduced along the deeper the soil depth. Propagule density was decreased in deeper the soil layer. Disease development rate treated alone with plant pathogens, Fusarium solani, Rhizoctonia solani, Cylindrocarpon destructans increased, but disease incidence rate reduced in treatment with combinations with antagonistic T. hamatum strain Tr-5.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.52 no.3
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• pp.303-310
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• 2007

Sweetpotato shoot tops (leaves, tips and petioles) are known to be very useful parts as vegetables because of their high nutritive values and great biomass yield. In this study, the phenolic compound contents, antibacterial activity, mutagenic activity, and antimutagenic activity were investigated in sweetpotato tips that were 10-15cm of shoot top including stems, petioles and tender leaves after sprout of storage roots. The study was done by extracting sweetpotato tips with 80% ethanol and the ethanol fraction was re-extracted with hexane, chloroform, ethyl acetate, butanol and water. In ethyl acetate and butanol fractions, total phenolic compounds contained 95. 6mg/g extract and 69.3 mg/g extract, respectively, The antibacterial activity was measured using the paper disk method with concentrations of 1, 2, 5 and 10 mg/disk of butanol and ethyl acetate fractions against L. monocytogenes and S. Typhimurium strains. Higher doses of solvent extracts showed the higher antibacterial activities. In addition, 5, 10 and 20 mg/mL of the extracts were tested to determine the antibacterial activity in liquid culture. The sweetpotato leaf extract by ethyl acetate showed 1 log reduction compared to control after 24 hrs on Listeria monocytogenes, but 20 mg/ml of butanol extract completely inhibited the growth of the pathogen after 12 hrs. The extracts from ethyl acetate or butanol on Salmonella Typhimurium did less than 1 log reduction during cultivation compared to control. The numbers of S. Typhimirium TA98 and TA100 revertant colonies were 29-33 and 159-188 CFU/plate, respectively, indicating that solvent extracts were no mutagenic activity. The antimutagenic test was performed by adding direct mutagen 2-NF and MMS, and butanol and ethyl acetate showed antimutagenic effect. Thus, this study showed that sweetpotato tips had high phenolic contents and both antimicrobiol and antimutagenic properties. Sweetpotato tips would be good nutritive source because of their high nutrient content without any toxicity in consuming.