• Journal of Plant Biology
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• v.35 no.2
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• pp.135-142
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• 1992

Shoot tip explants from germinated seeds of Alnus hirsuta were cultured on NT (Nagata and Takebe, 1971) mineral salts medium supplemented with 6% glucose, MS (Murashige and Skoog, 1962) vitamin mixture, polyvinylpyrrolidone (PVP) and $0-50\;\mu\textrm{M}$ 6-benzylaminopurine (BAP). Five $\mu\textrm{M}$ BAP was found to give the highest shoot multiplication rate. Accordingly about 200 shoots were obtained for further experiments by multiplying shoots on this medium for 4-5 months. Regardless of carbon sources, NT mineral medium produced 3-12 times of shoots than MS mineral medium did. On NT mineral medium, 3% sucrose, 3% glucose and 6% glucose yielded no significant differences. It was observed that media consisting of 1/4-1/2 strength NT mineral salts, 3% sucrose and $1-8\;\mu\textrm{M}$ IBA produced about 100% rooting rate. Almost 100% of the resulting plantlets survived after transfer to the soil by decreasing humidity stepwise.epwise.

• Korean Journal of Soil Science and Fertilizer
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• v.39 no.6
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• pp.396-402
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• 2006

Soil organic carbon has long been considered as the most critical factor to evaluate the soil quality, fertility, and fertilizer prescription. In addition, soil organic carbon may impact on greenhouse gas effects and global warming. Because of that, the management of soil organic carbon is increasingly important not only for improving soil quality but also for managing soil as a greenhouse gas source. Both wet and dry combustion have been used to determine soil organic carbon. Many benefits, such as automation and less labor, could the dry combustion method become more popular. Inorganic form of carbon could overestimate soil organic carbon when the dry combustion method was applied. Determination of soil inorganic carbon may contribute to the improved accuracy of soil organic carbon analysis using dry combustion method. Objectives of this research were 1) to develop soil inorganic carbon determination method using modified digital pressure calcimeter and 2) to evaluate soil organic carbon from calcareous soils using the dry and wet combustion method. Results showed that the significant linear relationship was found between soil inorganic carbon content and pressure calcimeter output. Inorganic carbon ranged from 22% to 28% of total carbon in the calcareous soil samples. Soil organic carbon content by dry combustion for calcareous soil was determined by subtracting inorganic carbon measured by the digital pressure calcimeter from total carbon. Soil organic carbon determined by dry combustion method was significantly correlated with that by wet combustion method. In conclusion, the digital pressure calcimeter may use to improve soil organic carbon determination for the calcareous soils by subtracting of soil inorganic carbon from total carbon determined by dry combustion method.

• Journal of the Korea Organic Resources Recycling Association
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• v.30 no.4
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• pp.67-83
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• 2022

Biochar is a carbon material produced through the pyrolysis of agricultural biomass with limited oxygen condition. It has been suggested to enhance the carbon sequestration and mineralization of soil carbon. Objective of this study was to investigate soil potential carbon mineralization and carbon dioxide(CO₂) emissions in different soils cooperated with barely straw and livestock manure biochars in the closed chamber. The incubation was conducted during 49 days using a closed chamber. The treatments consisted of 2 different biochars that were originated from barley straw and livestock manure, and application amounts were 0, 5, 10 and 20 ton ha^-1 with different soils as upland, protected cultivation, converted and reclaimed. The results indicated that the TC increased significantly in all soils after biochar application. Mineralization of soil carbon was well fitted for Kinetic first-order exponential rate model equation (P<0.001). Potential mineralization rate ranged from 8.7 to 15.5% and 8.2 to 16.5% in the barely straw biochar and livestock manure biochar treatments, respectively. The highest CO₂ emission was 81.94 mg kg^-1 in the upland soil, and it was more emitted CO₂ for barely straw biochar application than its livestock biochar regardless of their application rates. Soil amendment of biochar is suitable for barely straw biochar regardless of application rates for mitigation of CO₂ emission in the cropland.

• Journal of Applied Biological Chemistry
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• v.54 no.1
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• pp.7-14
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• 2011

Bacillus subtilis JK-1 showed degradation activity against crude oil, gasoline, kerosene, and light oil, and this strain was used as a crude biosurfactant producing microorganism in this study. To optimize the culture medium for production of crude biosurfactant, the influences of various carbon, nitrogen and mineral sources were assessed. The highest biosurfactant production by B. subtilis JK-1 was observed after 96 h cultivation, containing 1.0% (w/v) soluble starch as a carbon source and 0.5% (w/v) skim milk as a nitrogen source, and carbon to nitrogen concentraion (C/N) ratio was 2.0. For the biosurfactant production 0.1% (w/v) of $KNO_3$ was the most effective mineral source. Comparison of biosurfactant production indicates that B. subtilis JK-1 produces more biosurfactant in the optimum medium established in this study than LB and TSB. Under the optimum medium, the surface tension of culture broth of B. subtilis JK-1 was decreased from 47.3 dyne/cm to 24.0 dyne/cm after cultivation of 48 h.

• Electrical & Electronic Materials
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• v.36 no.1
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• pp.27-35
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• 2023

• Korean Journal of Environmental Biology
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• v.36 no.4
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• pp.665-671
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• 2018

This paper represents an investigation into the pattern of carbon transportation and composition on an open estuary in the transition zone between the river and marine environment in Tamjin River where stream water flows into the Gangjin Bay. To conduct the study, seven plots were established along an environmental gradient from river and estuary to the ocean. Surface water samples were collected thrice during the summer rainfalls and non-flooding seasons in 2017. The samples were then measured for the concentrations of dissolved organic carbon ([DOC]), particulate organic carbon ([POC]) and dissolved inorganic carbon ([DIC]). An analysis of the results showed that [POC] did not increase in the river even during the summer rainfall. However, [DOC] increased resulting in a higher [DOC]:[POC] ratios for the non-flooding season compared to summer rainfall events. On the other hand, the marine site of the estuary bay showed the highest [DIC] which was stable relative to those of river sites. The results suggest that in an open estuary zone, river and ocean supplied the open estuary zone with different types of carbon materials; mainly DOC supplied from the river and DIC sourced from the ocean.

• Microbiology and Biotechnology Letters
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• v.31 no.2
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• pp.171-176
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• 2003

Productivity of biosurfactant (rhamnolipid) by Pseudomonas aeuginosa F722 was investigated in the several culture conditions and culture composition. Biosurfactant production by P. aeuginosa F722 was amounted to 0.78 g/l as the result of the nitrogen sources and carbon sources without investing of optimum conditions. As for that one was investigated, biosurfactant production by P. aeruginosa F722 was amounted to 1.66 g/l. Biosurfactant production increased twofold because the composition of a modified C-medium was investigated efficiently. $NE_4$Cl or $NaNO_2$ inorganic nitrogens and yeast extract or trypton organic nitrogens were effective, but others inorganic nitrogens and organic nitrogens tested were not efficient far biosurfactant production by P. aeruginosa F722. The optimum concentration of $NH_4$Cl; inorganic nitrogen and yeast extract; organic nitrogen were 0.05% and 0.1%, respectively. In various carbon sources, others with the exception of hydrophobic property substrate (n-alkane) and hydrophilic property substrate (glucose, glycol) were not found to be effective fur biosurfactant production, and 3.0% was better in yield than other concentration of glucose. This yielded C-to-N ratios between 17 and 20. In our experiment, the highest biosurfactant production by P. aeruginosa F722 were observed in 5 days cultivation, containing glucose 3.0%, $NH_4$Cl 0.05%, and yeast extract 0.1% and C-to-N ratio was 20. Optimal pH and temperature for biosurfactant production were 7.0 and $35^{\circ}C$, respectively. Under the optimal culture conditions with glucose, biosurfactant production was amounted to 1.66 g/l. Velocity of biosurfactant production and strain growth increased after nitrogen depletion. The average surface tension of 30 mN/m after the 3 days of incubation under optimal culture condition was measured by ring tensionmeter.

• Korean Journal of Microbiology
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• v.47 no.3
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• pp.249-254
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• 2011

Mycophenolic acid blocking the synthesis of xanthosine monophosphate is a nonnucleoside inhibitor of inosine monophosphate dehydrogenase. Therefore mycopholoic acid is a drug currently used as immunosuppressive agent in transplantation of heart, kidney and liver. Mycophenolic acid has been industrially produced through fermentation process by fungus Penicillium brevi-compactum. In this study, the profile of mycophenolic acid fermentation was observed in 5L-jar fermentor to investigate the utilization of carbon and nitrogen sources and the production of mycophenolic acid. It was investigated that what kind of carbon sources was better to cell growth and mycophenolic acid production. Fructose was the best carbon source for mycophenolic acid fermentation, but it is the most expensive one. Thereafter molasses containing sucrose as the supply source of fructose was confirmed to be the best carbon source for the industrial production. Use of molasses increased the fermentation yield of mycophenolic acid more than two times higher than glucose. It was confirmed that urea was the best inorganic nitrogen source, which did not give rise to sudden drop of culture pH. Addition of urea increased the fermentation yield of mycophenolic acid about 3.6 times higher than addition of ammonium nitrate as control. Casein, peptone and casamino acid originated from milk protein increased the fermentation yield of mycophenolic acid about 3.4 times higher than control. Peptone and casamino acid, which are casein hydrolysates, increased cell growth considerably as well.

• Applied Biological Chemistry
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• v.23 no.4
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• pp.211-217
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• 1980

Using Streptomyces chibaensis, which produces a strong inulin-hydrolyzing enzyme, the optimum cultural conditions and composition of the medium for the production of inulase were studied. 1. The highest enzyme activity was obtained at pH 7.5 after 84 hours culture at $30^{\circ}C$. 2. None of carbon source better than inulin was found. 3. $(NH_4)_2HPO_4$ and corn steep liquor were favourable inorganic and organic nitrogen sources for the production of inulase. 4. $KCl,\;MgSO_4\;and\;FeSO_4$ as the metallic salts were effective for the enzyme production at their concentrations of 0.01, 0.05 and 0.0001%, respectively. 5. The highest production of inulase was obtained from the medium of inulin 1.0% and corn steep liquor 2.0% concentrations, respectively.

• Applied Biological Chemistry
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• v.39 no.3
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• pp.177-182
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• 1996

Effects of 14 carbohydrates supplied as carbon sources on cell growth and sporulation of, and the production of insecticidal crystal proteins by Bacillus thuringiensis strains were investigated in liquid cultures. Strains grew well in media containing any one of the 14 carbohydrates supplied, reaching maximum cell densities of $10^7{\sim}10^8\;cells/ml$ in 16.7 to 22 hours after inoculation depending on the strain. Spores first appeared in 16.7 to 24.7 hours after inoculation, and 80% sporulation was reached in 28 to 51.3 hours after inoculation depending on the strain. No change in pH of media was observed after cell multiplication. The production of total protein was highest when supplied with sucrose and was lowest with starch. More insecticidal crystal proteins were produced when supplied with glucose, lactose, maltose, or sucrose. The amount of insecticidal crystal proteins produced by the strains was proportional to that of the total protein. The relative amount of individual insecticidal crystal protein species produced by B.t. kurstaki and B.t. israelensis was not influenced by the carbohydrates supplied.