• Microbiology and Biotechnology Letters
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• v.16 no.6
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• pp.494-498
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• 1988

The optimum conditions for glucoamylase production, and ethanol productivity of the transformant TSD-14 were investigated as compared with the parental strains. The properties of TSD-14 were comparatively similar to the donor S. diastaticus IFO 1046 as regards the conditions of glucoamylase production and ethanol productivity. The soluble starch was the most effective carbon source for the glucoamylase production. While inorganic nitrogen sources did not prompt cell growth and enzyme production, the organic nitrogen sources generally enhanced both cell growth and glucoamylase production. The metal salts such as FeSO$_4$, MgSO$_4$, MnCl$_2$, and NiSO$_4$were favorable to the enzyme production. And the optium temperature and initial pH for glucoamylase production were 3$0^{\circ}C$ and 5. The transformant TSD-14 produced 8.3%(v/v) ethanol from 15% sucrose medium, 4.8%(v/v) ethanol from 15% soluble starch medium, and 7.5%(v/v) ethanol from 15% liquefied potato starch medium. The corresponding fermentation efficiency were 84% , 45% and 70%, respectively.

• Korean Journal of Plant Tissue Culture
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• v.27 no.6
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• pp.461-468
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• 2000

For the enhancement of ginsenoside production in hairy roots cultures of Panax ginseng, the uptake rate of inorganic elements and ginsenoside contents were investigated by different concentrations of about phosphorus (P $O_{4}$$^{[-10]}$ ) and nitrogen (N $H_{4}$$^{+}$, N $O_{3}$$^{[-10]}$ ) sources. According to increased phosphorus and nitrogen sources, the uptake rate of $Mg^{2+}$ and F $e^{2+}$ in ginseng hairy roots were significantly increased. The uptake rate of F $e^{2+}$ in 5.15 mM N $H_{4}$$^{+}$ was higher at 47.5% than that in 20.6 mM, whereas that of C $u^{2+}$ in 10.3 mM were higher at 123.1% than that in 41.2 mM. These results indicated that phosphorus and nitrogen sources act not only elevated growth of hairy roots but also the uptake-enhancement of the irons and other ions. The optimum concentration of phosphorus and nitrogen sources for the contents of free sugars were different to kinds of free sugars. The optimum concentration of phosphorus and nitrogen sources for the ginsenoside formation in ginseng hairy roots cultures were highest at the most low concentration of all. The contents of ginsenoside-R $b_2$and -Rc in 0.31 mM P $O_{4}$$^{[-10]}$ were increased to 44.7% and 29.9% than that in 0.62 mM P $O_{4}$$^{[-10]}$ , respectively. The contents of ginsenoside-R $b_2$ and -Rc in 5.15 mM N $H_{4}$$^{+}$ were increased to 21.7% and 31.9% than that in 10.30 mM N $H_{4}$$^{+}$, respectively. The contents of ginsenoside-R $b_2$and -Rc in 4.7 mn N $O_{3}$$^{[-10]}$ were also increased to 17.6% and 25.5% than that in 9.4 mM N $O_{3}$$^{[-10]}$ , respectively. These results indicate that enhancement of the ginsenoside formation in ginseng hairy roots was feasible by new medium modulation of concentration of phosphorus and nitrogen sources.rogen sources.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.53 no.1
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• pp.50-57
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• 2008

Winter season cultivation of rye as green manure for soybean have been a favorite with farmer because it could remove a risk of injury by continuous cropping and increase N uptake and yield of soybean. Effects of rye green manure on soybean N uptake, $N_2$ fixation and yield were investigated with $^{15}N$ as pot experiment in greenhouse in 2004 and field in 2005, respectively. The N derived from N fertilizer ($^{15}N$) in rye green manure increased with increasing of N fertilizer rate compared to N derived from soil. N uptake and DM yield of soybean at the pot with paddy soil was higher than those at the pot with upland soil mainly due to the increase of N uptake from paddy soil. Total $^{15}N$ recovery in soil was higher at rye green manure than no green manure because $^{15}N$ applied to rye plant was remained highly as soil organic N compared to chemical N fertilizer. $^{15}N$ recovery in soybean plant increased in proportion to amounts of N fertilizer applied to rye. The N fractions from $N_2$ fixation of soybean plant at the pot experiment in 2004 ranged from 92% to 95%, on the other hand those in field experiment in 2005 ranged from 82% to 84%. Estimation of amount of $N_2$ fixation was not different between Difference method and $^{15}N$ method in 2004 and 2005.

• Journal of Korean Society of Environmental Engineers
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• v.22 no.10
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• pp.1789-1797
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• 2000

The objective of this study was to assess parameters affecting nitrite accumulation, which offers advantages in terms of less aeration energy and carbon consumption for denitrification. The influence of the alkalinity to $NH_4{^+}-N$ concentration ratio, pH, FA(free ammonia) concentration and temperature on nitrite accumulation was investigated. The experiment was performed with supernatant from dewatering process of anaerobic digested sludge using a submerged biofilm reactor. The influent contains high strength of ammonium nitrogen and the alkalinity was insufficient for complete nitrification. An increased nitrite accumulation was observed with increase in alkalinity to $NH_4{^+}-N$ concentration ratio. The increase in alkalinity to $NH_4{^+}-N$ concentration ratio has been a maior reason for the high pH value and FA concentration in the reactor. It can be considered that selective inhibition of Nitrobacter can be causes of nitrite accumulation. The nitrite accumulation increased with increment of temperature at fixed alkalinity to $NH_4{^+}-N$ concentration ratio.

• KSBB Journal
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• v.15 no.6
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• pp.566-572
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• 2000

Experimental studies were carried out to develop an osmotolerant mutant of Candida magnoliae JH and to determine the optimum concentrations of carbon and nitrogen sources to improve erythritol yield and productivity. Mutants of C. magnoliae JH were prepared by treatment with ethylmethane sulfonate, and osmotolerant mutants were isolated from the agar plate colonies containing 2.5 M KCI. Among the mutants isolated, one mutant M26 was finally selected based on erythritol yield and productivity. In shake flask culture, glucose proved to be the best carbon source and the optimum yeast extract concentration was 5 g/L based on 100 g/L glucose. The erythritol yield and productivity of mutant M26 were greater than wild type in 100 g/L glucose medium. in the fermentation experiments, erythritol production increased with increased glucose concentration, up to a limit of 250 g/L. The maximum concentration of erythritol achieved 127.5 g/L, and the yield and productivity of erythritol production were 51.0% and 0.63 g/L-h, respectively.

• Journal of Korean Society of Environmental Engineers
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• v.27 no.3
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• pp.302-308
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• 2005

Nitrate is one of common contaminants frequently found in the bank filtrate. Biological autotrophic denitrification into permeable reactive barrier(PRB) system to reduce nitrate concentration in bank filtrate was implanted. The objectives of research are to investigate effect of inoculation, to evaluate alternative alkalinity sources, and to determine effect of hydraulic characteristics, such as retention time, flow rate on the performance of semi-pilot PRB system. Semi-pilot scale biological PRB system was installed using elemental sulfur and limestone/oyster shell as reactive materials near Nakdong River in Kyoungnam province, Korea. Nitrate concentration in bank filtrate was reduced by indigenous microorganisms in oyster shell as welt as by inoculating microorganisms isolated from the sludge of an anaerobic digester in a wastewater treatment plant. Oyster shell as well as limestone can be used as an alkalinity source. However, oyster shell resulted in suspended solids of effluent. As the flow rate in the system increased from 66 to 132 mL/min and accordingly the residence time decreased from 15 to 7.5 hours, nitrate concentration in effluent increased and nitrate removal efficiencies decreased from 75 to 58% at the fixed thickness of 80 cm of PRB.

• The Korean Journal of Mycology
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• v.24 no.2 s.77
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• pp.104-110
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• 1996

The effect of nutritional and cultural conditions for the production of anti-complementary polysaccharide from Pleurotus sajor-caju was studied. Maximum anti-complementary activity from its culture broth and mycelium was obtained by using lactose and maltose as a carbon source, respectively. Ammonium phosphate (monobasic) and serine were chosen for the highest activity among the inorganic nitrogen compounds and amino acids tested. Optimum temperature for the production of the anti-complementary polysaccharide was $25^{\circ}C$.

• Korean Journal of Environmental Agriculture
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• v.37 no.4
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• pp.235-242
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• 2018

BACKGROUND: About 81% of nitrous oxide ($N_2O$) emissions from agricultural land to the atmosphere is due to nitrogen (N) fertilizer application. Mitigation of $N_2O$ emissions can be more effective in controlling biochemical processes such as nitrification and denitrification in the soil rather than decreasing fertilizer application. The use of urease inhibitors is an effective way to improve N fertilizer efficiency and reduce $N_2O$ emissions. Several compounds act as urease inhibitors, but N-(n-butyl) thiophosphoric triamide (NBPT) has been used worldwide. METHODS AND RESULTS: Hot pepper and chinese cabbage were cultivated in five treatments: standard fertilizer of nitrogen-phosphorus-potassium(N-P-K, $N-P_2O_5-K_2O$: 22.5-11.2-14.9 kg/ha for hot pepper and $N-P_2O_5-K_2O$: 32.0-7.8-19.8 kg/ha for chinese cabbage), no fertilizer, and NBPT-treated fertilizer of 0.5, 1.0, and 2.0 times of nitrogen basal application rate of the standard fertilizer, respectively in Gyeonggi-do Hwaseong-si for 2 years(2015-2016). According to application of NBPT-treated fertilizer in hot pepper and chinese cabbage, $N_2O$ emission decreased by 19-20% compared to that of the standard fertilizer plot. CONCLUSION: NBPT-treated fertilizer proved that $N_2O$ emissions decreased statistically significant in the same growth conditions as the standard fertilization in the hot pepper and chinese cabbage cultivated fields. It means that NBPT-treated fertilizer can be applied for N fertilizer efficiency and $N_2O$ emissions reduction.

• KSBB Journal
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• v.7 no.3
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• pp.166-171
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• 1992

Zoogloea ramigera 115 was cultured for biopolymer production and its bioflocculant usages. Cultural conditions of the organism were examined with regard to high production of the microbial polysaccharide. The most suitable medium was found to contain glucose as a carbon source, $NaNO_3$ as a nitrogen source, and yeast extract as an organic nutrient. The initial pH of 6.0 proved to optimal. The biopolymer was extracted effectively using ultrasonication and high speed centrifugation, followed by propanol addition. Jar test results indicate that the polysaccharide produced by the organism is an effective flocculant.

• Microbiology and Biotechnology Letters
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• v.20 no.2
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• pp.207-212
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• 1992

An anti-inflammatory agent, serratiopeptidase, was produced from the culture of the Serratia marcescens. The effects of carbon sources, nitrogen sources and inducers on the production were investigated. Citrate was found to be inhibitory in the production of serratiopeptidase. The enzyme was synthesized in the synthetic medium without inducers, albeit low level of synthesis. But the synthesis was increased by the addition of proteinaceous substrate and leucine. Induction of extracellular proteinase by its end-product was discovered, which is not common in the proteinase synthesis in the bacteria. By the glucose fed-batch culture, we found the possible catabolite repression on the production of serratiopeptidase.