• Proceedings of the Plant Resources Society of Korea Conference
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• 2002.11b
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• pp.60-60
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• 2002

This study was excuted to decide the physiological characteristics of Fomers fomentarius. F. fomentarius was tested to select pertinent substract, temperature and pH range for the growth. Mycelial growth of F. fomentarius was mostly supported on MYPA among other tested synthetic or semi-synthetic media. The temperature range for pertinent mycelial growth was about 22~32$^{\circ}C$ and mostly stimulated at $25^{\circ}C$. And the pertinent pH range of MYPA was 5.0~6.0. The required carbon and nitrogen source for mycelial growth of F. fomentarius was tested. The mycelial growth was mostly stimulated by soluble starch at content. The carbon sources for pertinent mycelial growth was glucose or starch. And the nitrogen source for pertinent mycelial growth was yeast

• Proceedings of the Plant Resources Society of Korea Conference
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• 2002.11b
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• pp.61-61
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• 2002

This study was excuted to decide the physiological characteristics of Kuehneromyces mutabilis. K. mutabilis was tested to select pertinent substract, temperature and pH range for the growth. Mycelial growth of K. mutabilis was mostly supported on MYPA among other tested synthetic or semi-synthetic media. The temperature range for pertinent mycelial growth was about 25~32$^{\circ}C$ and mostly stimulated at $25^{\circ}C$. And the pertinent pH range of MYPA was 5.0~6.0. The required carbon and nitrogen source for mycelial growth of K. mutabilis was tested. The mycelial growth was mostly stimulated by soluble starch at content. The carbon sources for pertinent mycelial growth was mannose or glucose. And the nitrogen source for pertinent mycelial growth was yeast extract or peptone.

• The Korean Journal of Mycology
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• v.28 no.2
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• pp.81-87
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• 2000

The optimal synthetic medium, temperature and pH range for the mycelial growth of Cordyceps scarabaeicola were PDA, $25^{\circ}C$, and pH $8.0{\sim}8.5$, respectively. The effects of carbon sources, nitrogen sources and mineral salts on mycelial growth were superior to lactose, ammonium phosphate and $CaCl_2$, respectively. Liquid spawn culture was selected out BM(brown sugar 3%, soybean flour 0.3%, potassium phosphate 0.05%, magnesium sulfate 0.05%) medium.

• Environmental Engineering Research
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• v.20 no.4
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• pp.377-382
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• 2015

The high concentration of nitrogen and phosphorus in wastewater incorporated with the ability to use carbon dioxide as the carbon source make the microalgae become more attractive in wastewater treatment process. This study evaluates the optimal conditions for the digestion of settelable solids from the recirculating aquaculture system to produce the biomass of the green microalga Scenedesmus sp. After solids separation, aerobic digestion of settleable solids under disperse condition produced nitrate as the final product of consequently ammonification and nitrification processes. With the optimal digestion procedure, nitrate concentration during aerobic digestion in 2000 mL vessel increased from $9.63{\pm}0.65mg\;N/L$ to $58.66{\pm}0.06mg\;N/L$ in 10 days. Thereafter, cultivation of Scenedesmus sp. was performed in 1000 mL Duran bottle with air bubbling. The highest Scenedesmus sp. specific growth rate of $0.321{\pm}0.01/d$ was obtained in treatment using liquid fraction after aerobic digestion as the whole culture medium for Scenedesmus sp. cultivation. With this study, digestion of $8,800{\pm}128.12mg\;dry\;weight/L$ of settleable solids from fish pond finally produced $1,235{\pm}21mg\;dry\;weight/L$ of Scenedesmus sp. biomass.

• Journal of Korean Society on Water Environment
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• v.21 no.6
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• pp.630-636
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• 2005

Groundwater contamination by nitrate exceeding water quality criteria (10 mg $NO_3{^-}-N/L$) occurs frequently. Fumarate, acetate, formate, lactate, propionate, ethanol, methane and hydrogen gas were evaluated for their nitrate removal efficiencies and removal rates for in situ bioremediation of nitrate contaminated groundwater. Denitrification rate for each substrate was in the order of: fumarate > hydrogen > formate/lactate > ethanol > propionate > methanol > acetate. Microcosm studies were performed with fumarate and acetate. When fumarate was used as a substrate, nitrate was removed 100 percent with rate of 0.66 mmol/day while conversion rate from nitrate to nitrogen gas or another by-product was 87 percent. 42 mg of fumarate was needed to remove 30 mg $NO_3{^-}-N/L$. When using acetate as carbon source, 31 percent of nitrate was removed during initial adjustment period. Among removed fraction, however, 83 percent of nitrate removed by cell growth. Overall nitrate removal rate was 0.37 mmol/day. Acetate showed longer lag time in consumption compared to that of nitrate, which implying that acetate would be better carbon source compared to fumarate as more amount was utilized for nitrate removal than cell growth.

• Journal of Korean Society of Water and Wastewater
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• v.12 no.2
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• pp.83-89
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• 1998

The drinking water supply in Cheju entirely depends on the ground water and recently the polluted ground water bores are increasing. In 1993 Cheju Province Health-Environment Institute reported that the ground water quality of 26 of 98 bores under the drinking water quality standard. Therefore there are many investigation in the needs of the nitrate removal in the drinking water in the regin with no alternative water resources. In this study, the following results are obtained to remove the nitrate in biofilm filtration process in which uses ethanol as external carbon source. Over 90% of nitrate is removed after 10 days of experiment. The nitrate removal rate on filtration velocity is about 100% at 50m/day and 100m/day, and about 56% at 200m/day. The removal rate is reduced in 27% at 400m/day. Using ethanol as the external carbon source, denitrification kinetic is 1st-order. Denitrification constant k is 8.004($hr^{-1}$). The amount of the denitrificated-Nitrogen is increased as the contact time increased. Deoxydation rate constant ${\gamma}$ is 11.895($hr^{-1}$). 0.968g of ethanol(as TOC) is needed to remove 1g of nitrate and 0.291g is required to remove 1g of dissolved oxygen.

• Environmental Engineering Research
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• v.16 no.4
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• pp.213-218
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• 2011

The two-stage intermittent aeration activated sludge process (IAP) and dynamic-flow intermittent aeration activated sludge process (DFP) were investigated for the nutrient removal of domestic wastewater. Three sets of IAP and one set of DFP were operated. The fermented settled sludge taken from the primary settling tank was added to two IAP and one DFP as an external electron donor, with one IAP, in which an external carbon source was not added, as a control. All the systems were operated at a sludge retention time of 20 days and a hydraulic retention time of 12 hr. A Higher denitrification rate was observed with the fermented settled sludge for the denitrification compared to the process without the addition of the organic source. The result indicates that the fermented acid from the primary domestic sludge has been proved to be an excellent electron donor for denitrification and biological phosphorus removal with IAP and DFP in treating relatively low C/N ratio(Carbon / Nitrogen ratio) wastewater. Phosphate accumulating organisms have a capability of competing with denitrifiers in the presence of volatile organic acids under anoxic conditions.

• Journal of Environmental Science International
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• v.13 no.7
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• pp.675-680
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• 2004

This study was conducted to remove organics and nutrients using 2 stage intermittent aeration reactor. First reactor, using suspended microbial growth in intermittent aeration instead of anaerobic reactor in the typical BNR process, used minimum carbon source to release P, and it was possible to reduce ammonia loading going to second reactor. In the second reactor, using moving media intermittent aeration, it was effective to reduce nitrate in non-aeration time by attached microorganisms having long retention time. In aeration time, nitrification and P uptake were taken place simultaneously. From the experiment, two major results were as follows. First, the removal of organics was more than 90%, and optimum aeration/non-aeration time ratio for organic removal was corresponded with aeration/non-aeration time ratio for nitrogen removal. Second, in the first reactor, optimum aeration/non-aeration time ratio was 15/75 (min.) because it was necessary to maintain 75 min. of non-aeration time to suppress of impediment of return nitrate and to lead release of phosphate. In the second reactor, optimum aeration/non-aeration time ratio was 45/90 (min.).

• Journal of the Korean Society of Food Science and Nutrition
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• v.19 no.5
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• pp.429-433
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• 1990

Production and properties of invertase from. Aspergillus niger were investigated. Inuli and sucrose were best carbon source and yeast extract was most suitable for the production of the enzyme among tested carbon and nitrogen sources. The enzyme was maximally produced by cultivating the organism at medium of pH 4.5 and temperature of 3$0^{\circ}C$ The optimum pH and temperature for the enzyme activity were pH 5.0 and temperature of 5$0^{\circ}C$ respectively Among tested metal ions Hg2+ Cu2+ and Ag+ ions inhibited the enzyme activity drastically.

• Journal of Microbiology and Biotechnology
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• v.15 no.4
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• pp.689-693
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• 2005

Bacillus sp. JB-99, when grown in a chemically defined medium containing lactose as a carbon source, yielded 3,860 U/ml extracellular $\beta$-mannanase, which was high compared to other examined carbon sources. Among the nitrogen sources, yeast extract enhanced the enzyme activity. The enzyme production was growth-associated. The enzyme was optimally active at $65^{\circ}C$, pH 10, and had a half-life of 190 min at $65^{\circ}C$. N-Bromosuccinamide and $AgNO_3,\;CuSO_4$, and $HgCl_2$ strongly inhibited the enzyme, whereas $Ca^{2+}$ stimulated the enzyme activity. The $\alpha$-galactosidase enzyme production was not found in any of the enzyme assays.