• Korean Journal of Environmental Agriculture
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• v.26 no.1
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• pp.25-35
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• 2007

Excess runoff contaminated with N and P can impact the quality of downstream water. It has been known that aquatic plants improve the water quality through their intake of organic or inorganic nutrients. This study was conducted to select aquatic plants having high purification ability for nutrient N and P, and mineral nutrients related to EC such as K, Ca, Na, Cl, and $SO_4$ in raw sewage water in greenhouse. We assessed nutrient phytoremediation potential of alien hydrophyte and hydro-crop as well as native landscape hydrophyte to select suitable aquatic plant applied to artificial wetland and buffering site of stream-side. The amount of irrigation water during whole growing period of aquatic plane ranged from 225 L $m^{-2}$ to 444 L $m^{-2}$. Oryza sativa, Typha orientalis, Zizania latifolia, Aster subulatus, Coix lachryma-jobi var. mayuen, Paspalum disdichum var. indutum which had high biomass consumed the large amount of irrigation water over 350 L $m^{-2}$. As a result of analysis of water purification effect N and P content of shoot biomass, and media soil after experiment, Oryza sativa, Zizania latifolia, Aster subulatus, Coix lachryma-jobi var. mayuen, Paspalum distichum var. indutum showed high purification ability about eutrophication elements such as T-N and T-P. It is presented that Pistia stratiotes, Eichhornia crassipes, and Paspalum distichum var. indutum had excellent purification ability about K, Ca, Na, and Cl. Moreover, Paspalum distichum var. indutum greatly removed $SO_4$ in row sewage water.

• Analytical Science and Technology
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• v.28 no.1
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• pp.33-39
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• 2015

CdS-QD particles are a nano-sized semiconducting crystal that emits light. Their optical properties show great potential in many areas of applications such as disease-diagnostic reagents, optical technologies, media industries and solar cells. The wavelength of emitting light depends on the particle size and thus the quality control of CdS-QD particle requires accurate determination of the size distribution. In this study, CdS-QD particles were synthesized by a simple ${\gamma}$-ray irradiation method. As a particle stabilizer polyvinyl pyrrolidone (PVP) were added. In order to determine the size and size distribution of the CdS-QD particles, sedimentation field-flow fractionation (SdFFF) was employed. Effects of carious parameters including the the flow rate, external field strength, and field programming conditions were investigated to optimize SdFFF for analysis of CdS-QD particles. The Transmission electron microscopy (TEM) analysis show the primary single particle size was ~4 nm, TEM images indicate that the primarty particles were aggregated to form secondary particles having the mean size of about 159 nm. As the concentration of the stabilizer increases, the particle size tends to decrease. Mean size determined by SdFFF, TEM, and dynamic light scattering (DLS) were 126, 159, and 152 nm, respectively. Results showed SdFFF may become a useful tool for determination of the size and its distribution of various types of inorganic particles.

• The Korean Journal of Mycology
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• v.11 no.3
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• pp.121-128
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• 1983

Nutritional and physio-chemical conditions for mycelial growth and fruit-body formation of Pleurotus florida were determined in synthetic media. Mannitol and sucrose were good sugar substances for the mycelial growth and fruit-body formation whereas less mycelial growth and no fruit-body formation was obtained with arabinose, lactose and inulin. The optimum concentration of mannitol was about 2%. Peptone as a nitrogen sources resulted in a rapid mycelial growth and fruit-body formation with higher yield, but nitrite-nitrogens inhibited the mycelial growth. The higher yield was obtained with 0.2% peptone. Among the vitamins used, the greatest mycelial growth and fruit-body formation brought about by thiamine and folic acid. $KH_2PO_4$ and $MgSO_4$ at 0.2% and 0.02%, respectively, were effective for the mycelial growth and fruit-body formation, but other inorganic salts used were ineffective. The optimum temperature for mycelial growth and fruit-body formation were $25^{\circ}C$ and $20^{\circ}C$, respectively, and light intensity of $100{\sim}500\;lux$ and pH 6.0 appeared to be effective.

• Korean Journal of Food Science and Technology
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• v.26 no.5
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• pp.644-648
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• 1994

Lactic acid bacteria(LAB) and its metabolites were tested for their inhibitory effect on the growth of Staphylococcus aureus in vitro. When S. aureus and LAB were incubated simultaneously in MRS broth, the growth of S. aureus began to be suppressed after 12 hour of incubation, completely inactivated within 24 hour of incubation by L. lactis and 48 hour by L. casei, L. acidophilus, and Sc. thermophilus. The pH values of media incubated by S. aureus and LAB were about 4.5 at 12 hour of incubation and 3.5 at 48 hour. The metabolites of the four LAB all exerted antibacterial activity on the growth of S. aureus in TS broth, but is got lost the antibacterial activity by heating ($100^{\circ}C,\;20\;min$). On treating metabolites with catalase, only L. lactis were lost its antibacterial activity. Organic acids (acetate, lactate) showed more active inhibition than inorganic acid (HCl) at pH 3.5, 4.5 but there is no significant differance at pH 5.5, 6.5.

• The Korean Journal of Mycology
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• v.22 no.3
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• pp.266-275
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• 1994

Brewer's yeast extract can be used as a good substrate for the culture of Lentinula edodes Mycelia(LEM). We found that it was better to filter the extract through three kinds of sieves and then to heat for hydrolysis and concentration at $90^{\circ}C$ prior to use. Also the maximum condition for the growth of LEM was investigated. We found that addition of inorganic salts such as calcium enhanced the growth of LEM. On the other hand, addition of carbon and nitrogen sources to the medium did not affect, and even inhibited under certain conditions, the growth of LEM. The maximum temperature for the growth of LEM was around $25^{\circ}C$. Also, it grows better when agitated by shaking at 100 rpm for airration. The appropriate concentration of the extract to use was 10%. Under these conditions, LEM could reach to the confluency after cultivation of 12 days. Our extract formula seems better than other available media for LEM growth, producing higher crude protein content and better taste.

• KSBB Journal
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• v.8 no.3
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• pp.193-199
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• 1993

To find out the optimum conditions for indigo cell culture in air-lift bioreactor, effects of media composition including nutrients and precursors of the indigo colorants on the cell growth and characteristics of the cell growth under various cultural conditions were analyzed. Optimum cultural conditions were tested and the growth characteristics were analyzed in external and internal loop type air-lift bioreactors during 14-day culture. Better cell growth was obtained when the inoculum size was higher in the range of 0.5∼2.5% packed cell volume tested. In the sucrose concentration of 2 to 4%, the cell growth was better when the sucrose concentration was 4% (w/w) in both types of reactors. Sucrose was used up in the early stage of exponential phase of growth At the optimum concentration of a Precursor tryptophan at 1 U UW was 3.8 g/l in internal loop bioreactor, and 3.5 g/l in external one after 14 days of cultivation. Addition of indole showed negative effect on cell growth of suspension culture in air-lift biorector culture and cell mass of 2.5 g/l and 2.2 g/l were obtained in external and internal loop bioreactor, respectively. Selected inorganic nitrogen source potassium nitrate showed about 110% increase in cell growth than that of control. DCW was 16.34 g/l under optimum conditions during 14-day cultivation in internal loop bioreactor.

• The Korean Journal of Mycology
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• v.42 no.4
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• pp.312-321
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• 2014

Tricholoma bakamatsutake is one of the edible ectomycorrhizal mushrooms as an allied species of Tricholoma matsutake. This is the first report on physical characteristics of T. bakamatsutake strains collected from Quercus mongolica forests in Korea. The pure cultures of these strains were isolated from the tissues of fruit bodies and the culture characteristics were investigated under different conditions (media, temperatures, nitrogen sources). Most strains showed the highest mycelial growth on potato dextrose agar (PDA) at 20 or $25^{\circ}C$. Two strains of T. bakamatsutake preferred the ammonium-form rather than the nitrate-form as an inorganic nitrogen source. T. bakamatsutake showed significantly slower mycelial growth when compared with T. matsutake from a Korean forest, although the optimum culture conditions for the two allied species were similar. We also tested the ability to form mycorrhizae as well as cellulase activity of T. bakamatsutake. All strains showed cellulase activity on a carboxymethylcellulose (CMC) agar plate. The mycorrhizae on axenic Pinus densiflora seedlings were formed by two strains of T. bakamatsutake after 3 or 8 months of inoculation. P. densiflora seedlings inoculated with T. bakamatsutake had a much higher biomass than un-inoculated seedlings.

• Korean Journal of Soil Science and Fertilizer
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• v.35 no.6
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• pp.327-334
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• 2002

Method of besoil analysis were difficult to be applied universally since the use and the source material of bedsoils are diverse from country to country. Korean Standard Methods for Bedsoil Analysis was developed to measure the particle and bulk density. Fifty-three samples for horticultural bedsoil and nine samples for paddy rice bedsoil in the current market were collected. Particle density was measured by electrical pyconometer with He gas, and bulk density by the sandbox method, free fall method, plunger compaction method, free fall and plunger method, and sample weight compaction method. While the use of glass pycnometer which measures particle density to fill blank space with water was inappropriate due to floating organic and calcined inorganic materials in the water, the electrical pycnometer with gas type was suitable considering speed and accuracy. For bulk density, the sandbox method recommended as European Standard Method was more reasonable in principle than other methods. However, this method requires expensive apparatus and intricate process. Plunger compaction method was proposed as standard method, since it had higher consistence with the sandbox method than other methods, as well as an advantage of easy and prompt measurement. Particle density of bedsoil ranged $1.48{\sim}2.67Mg\;m^{-3}$(mean $1.93Mg\;m^{-3}$) for horticultural bedsoil and $2.33{\sim}2.67Mg\;m^{-3}$ (mean $2.43Mg\;m^{-3}$) for paddy rice bedsoil by the electrical pycnometer with He gas. Bulk density of bedsoil ranged $0.11{\sim}0.40Mg\;m^{-3}$ (mean $0.22Mg\;m^{-3}$) for horticultural bedsoil and $0.84{\sim}1.26Mg\;m^{-3}$(mean $1.01Mg\;m^{-3}$) for paddy rice bedsoil by plunger compaction method.

• Korean Journal of Environmental Agriculture
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• v.25 no.1
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• pp.25-33
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• 2006

Objectives of this experiment were to select of the optimum water plant and to investigate the removal efficiency of the major nutrients in the constructed wetland by natural purification method for municipal sewage treatment in the farming and fishing village. For the experiment we used "constructed wetland" which was consisted of aerobic (vertical filter system) and anaerobic systems (horizontal filter system). Both systems were filled with gravel and filter media, and grew water plants on top of them. And then, we investigated several items such as sewage treatment efficiency, growth status of water plants and the absorbed amount of inorganic element in water plants with periodical periods. In aerobic area, removal efficiencies of BOD, COD, T-N and T-P were over 92%, 74%, 25% and 57%, respectively, and then when the water is passed through anaerobic area, the efficiency was over 96%, 84%, 44% and 71%, respectively, which was increased more treatment efficiency than that of aerobic area. Absorption amount of nitrogen and phosphorous in Miscanthus sacchariflorus BENTH were the highest in the water plants as 17.7 and 2.41 g/plant in the aerobic area, respectively. Absorption amounts of nitrogen and phosphorous in Scirpus tabernaemontani GMEL were the highest in the water plants as 8.7 and 1.13 g/plant in the anaerobic area, respectively. For the selection of optimum water plants in the constructed wetland by natural purification method for municipal sewage treatment, it were observed that there were Miscanthus sacchariflorus BENTH, Phragmites japonica STEUD and Phragmites communis TRINIUS in the aerobic area and were Zizania latifolia TURCZ, Scirpus tabernaemontani GMEL, Typha orientalis PRESL, Iris pseudoacorus L and Cares dispalata BOOTT in the anaerobic area.

• Korean Journal of Soil Science and Fertilizer
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• v.9 no.1
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• pp.25-31
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• 1976

The purpose of this investigation is to find out the effects on the changes of microflora and the effects on the inorganic nutrients of the fertilized soil and the non-fertilized soil under submerged condition with the treatment of butachlor at the levels of 250, 500, and 1000ppm respectively. The survey was made within the period of 72 days with 7-day intervals under the incubated condition. The result came out to be the following: 1. The Fluctuated changes of soil microflora A. Bacteria: The plots treated by 500ppm of butachlor in case of non-fertilized soil showed the decreasing tendency of bacteria until 21st day. But there were no effects on the other plots. The plots treated by 250ppm and 500ppm in case of fertilized soil showed decreasing tendency on the 7th day, and 1000ppm until 21st days. B. Actinomycetes: There was no effects on the actinotnycetes in case of the non-fertilized soil but the fertilized soil showed some decrease. In both cases, actinomycetes have generally shown a little increase according to the time passage. C. Fungi: In both cases of the fertilized soil and the non-fertilized soil, the plots treated by the media showed some decreasing tendency in comparison with the control plots. There was no change to the number of fungi according to the time passage. 2. The fluctuated changes of nutrient A. $NH_4-N$: The whole plots showed decrease of $NH_4-N$ by adding butachlor. The higher the intencity of butachiar showed the more decreasing tendency of $NH_4-N$. In case of the non-fertilized soil, the highest increase of $NH_4-N$ appeared from the 7th day to 14th day, but showed degrease thereafter. The increasing tendency was seen in case of the fertilized soil plots. B. $NO_3-N$: Decrease of $NO_3-N$ was shown in the whole plots by the treatment of media, and on the 44th day of cultivation almost none of $NO_3-N$ was detected. C. $NO_2-N$: Whole plots showed the number of $NO_2-N$ highest on the 35th day, and there were nothing measurable on the 44th day. D. Eh: On the fertilized soil, the condition of reduction went on strongly but on the non-fertilized soil, the condition of reduction kept on till 42nd day and oxidation appeared thereafter.