• KOREAN JOURNAL OF CROP SCIENCE
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• v.28 no.1
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• pp.81-88
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• 1983

This experiment was conducted to study about influenced inorganic element contents of flag leaf and chaff with different nitrogen and silicate application in Jinan (sea level 303m). The recommended rate of fertilizer application above N 15kg/10a was poor for dry production increment in cold in July elevation and was demanded increment of silicate. In the elevation of cold in July high rates of nitrogen application produced more incomplete grain and a reduced cold tolerance. These effects were due to over-content of soluble nitrogen within flag leaf and disturbance of uptaking potassium and silicate. On the other hand, the application of silicate could increase yield by promoting resistance to cold- damage. The application of increasing level of nitrogen resulted in increasing the contents of total nitrogen and phosphate in both sterile and fertile glumes. The contents of potassium and calcium were the highest at the level of nitrogen 10 - 15kg/10a, but magnessium was rather high at low nitrogen levels. It is interesting that at any level of nitrogen, over 6% higher silicate contents were noted in the fertile chaff than in the sterile chaff. Application of increasing level of silicate fertilizer decreased total nitrogen contents, but increased the contents of phosphate, potassium. and silicate in the chaff. Increasing rate of silicate content by increasing silicate addition was remarkably higher in the fertile chaff than in the sterile chaff.

• 한국생물공학회:학술대회논문집
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• 2005.10a
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• pp.250-255
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• 2005

Trichoderma inhamatum KSJ1, a filamentous fungus, isolated from rotten wood showed high ability to hydrolysis of cellulosic materials. Enzyme productivity by strain KSJ1 was high in the cultivation using carbon sources such as cellulosic materials and lignocellulosic wastes as rice straw and paper waste. In previous study peptone was one of optimum organic nitrogen sources in producing cellulases for saccharification of food wastes. However, it was too expensive using peptone as organic nitrogen source, so, in this study, soybean and yeast were applicated to substitute peptone. Yeast showed producing high enzyme activity, so it was estimated that yeast is available in producing cellulase using Trichoderma inhamatum KSJ1 at industrial Production.

• The Korean Journal of Mycology
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• v.26 no.3 s.86
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• pp.361-364
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• 1998

Among the organic sources of nitrogen tested, yeast extract and soytone were excellent for the mycelial growth of Tricholoma matsutake DGUM 26001. The mycelial growth was enhanced, when yeast extract at the concentration up to 1.0% was added to the starchpyridoxine medium. After 30-day cultivation of the mycelia at $24^{\circ}C$ in the medium supplemented with yeast extract, 518 mg/50 ml of dry mycelia could be harvested.

• Korean Journal of Optics and Photonics
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• v.6 no.2
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• pp.122-129
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• 1995

질소 기체의 온도변화에 따른 질소 레이저의 동작 특성을 조사하고 실험에 의해 얻은 E/P값을 이론치와 비교 연구하였다. 이를 위하여 레이저 관의 길이가 200mm이고, 다중 평행판 축전기형 전송 회로 및 질소 기체의 온도 조정 장치로 구성된 질소 레이저를 제작하였다. 반복률 20Hz에서 스파크 갭의 전극 거리 4mm일 때 최대출력을 얻었으며 최적동작 조건은 질소 기체 온도 $30^{\circ}C$, 기체 압력 70torr이었다. 이때의 E/P는 411V/cm.torr이었다. 한편 질소 기체의 온도가 증가함에 따라 최적 동작 조건은 높은 압력 쪽으로 이동하는 경향을 보였고 이때 E/P값은 감소하는 것으로 나타나 이론과 어느 정도 일치함을 알 수 있었다.

• KSBB Journal
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• v.11 no.2
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• pp.246-253
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• 1996

An obligatory methanotroph Methylosinus trichosporium OB3b was cultivated for the production of poly-${\beta}$-hydroxybutyric acid(PHB) in shake-flask using liquefied natural gas(LNG) as the sole source of carbon and energy. The maximal specific growth rate decreased by 40% using LNG compared with that obtained with pure methane. This is attributed to the inhibition by ethane and propane presents in the LNG as impurities. For the production of PHB, two-stage culture separating the production stage from the growth stage was carried out. PHB accumulation was observed after switching nutrient-sufficient to nutrient-limited condition of non-carboneous component (NO3-, PO43-, K+, Na+, Fe2+, or Mg2+). The limitation of K+ or Mg2+ resulted in relatively high PHB content, but the highest content was obtained by nitrate limitation. The optimal pH and temperature for PHB accumulation was 7.0 and $30^{\circ}C$. Under the optimal condition the maximal PHB content was about 45% after 4-day cultivation.

• Journal of Mushroom
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• v.18 no.4
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• pp.311-316
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• 2020

The effect of the nitrogen content of sawdust medium (1.2~1.8%) and the restriction stage temperature (2, 4, and 6℃) on the growth and storage characteristics of Flammulina velutipes (winter mushroom) were investigated. With increased nitrogen content, the growth days shortened and the yield of the fruiting body increased. The effect of restriction temperature on the growth of the fruiting body differed depending on the nitrogen content. No difference in restriction temperature was evident for T1 with a low nitrogen content of 1.28%. In medium with a nitrogen content ≥1.55%, the yield and length of the pileus and stipe increased as the restriction temperature decreased. The weight loss ratio according to the storage period did not change according to the nitrogen content in the medium. A low weight loss ratio of 1.50 to 1.93% was observed at a restriction temperature <4℃. When T3 with high nitrogen content in the medium was treated at a restriction temperature of 4℃, the fruiting body color values after 31 days of storage were 84.81 (L) and 6.3 (ΔE). This color change was minute compared to that after other treatments. The sensory characteristics score was 5.2 after 31 days of storage, and the quality remained acceptable for consumption.

• KSBB Journal
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• v.10 no.2
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• pp.170-175
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• 1995

The effect of nitrogen source on production of a high viscosity exopolysaccharide, methylan, from methanol by Mentylobacterium organophilum was investigated in fed-batch culture. During the fermentation, cells continued to grow even after the nitrogen source added to the medium was depleted and methylan production was stimulated under the condition which ammonium ion was depleted. Cell growth increased proportionally to the initial concentration of ammonium ion in the medium, but methylan production was significantly inhibited at the high concentration of ammonium ion. As the initial concentration of ammonium ion increased, the specific growth rate, the specific product formation rate and the specific substrate consumption rate decreased due to the inhibitory effect of excess ammonium ions. In order to reduce the inhibitory effect by high concentration of ammonium ion. The control of ammonium ion concentration within the desired level(usually $0.45g/\ell$) was necessary. When ammonium ion concentration was maintained below $0.15g/\ell$ by exponential feeding, methylan production could be increased up to $12.5g/\ell$.

• KSBB Journal
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• v.19 no.1
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• pp.78-82
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• 2004

Experiments were carried out to select an organic nitrogen source and optimize the culture conditions for the production of arachidonic acid by Mortierella alpina DSA-12. Corn steep powder(CSP) was selected as an organic nitrogen source based on arachidonic acid production and raw material price. The optimum C/N ratio was in the range of 15 to 17 with the medium containing glucose as carbon source and CSP as nitrogen source. The optimum culture conditions for arachidonic acid production showed 500 rpm agitation and 25$^{\circ}C$ culture temperature at 0.5 vvm aeration. Under the optimum conditions, the concentration of cell, total lipid and arachidonic acid were 21.8 g/L, 10.2 g/L and 3.70 g/L, respectively, from 50 g/L glucose and 18 g/L CSP. In the 500 L fermenter with 0.5 vvm aeration and 200 rpm agitation, the concentration of cell, total lipid and arachidonic acid were 19.8 g/L, 9.1 g/L and 3.67 g/L, respectively, from 50 g/L glucose and 18 g/L CSP. This result showed that an arachidonic acid production could be possible with a bench-scale fermenter using corn steep powder as a nitrogen source.

• Microbiology and Biotechnology Letters
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• v.12 no.4
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• pp.271-276
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• 1984

Effect of C/N ratios on the cell growth, cell lipid, cell protein and fatty acids of Rhodotorula sp. was examined. At low concentration of nitrogen in cultural medium the growth of the yeast was retarded, whereas its growth was favorable at high concentration but lipid yield was decreased due to a high content of cell protein. In order to increase lipid yield, the optimum C/N ratio obtained was 45-50 (5% glucose, 0.0414% nitrogen). During the cultivation cell protein synthesis occurred mainly in initia stage and the lipid was accumulated rapidly at the late phase. The highest content of total fatty acid was observed at the optimum C/N ratio. The higher C/N ratio was the more unsaturation degree of fatty acid decreased. It was attributed principally to a decreased oleic acid with palmitic acid increased. No significant changes occurred in content of other fatty acids.

• KSBB Journal
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• v.10 no.2
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• pp.137-142
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• 1995

When Escherichia coli W, which is able to utilize sucrose as a carbon source, harboring a high-copy-number plasmid (pSYL105) containing the Alcaligenes eultrophus polyhydroxyalkanoate(PHA) biosynthetic genes was cultured in a defined medium, the final poly(3-hydroxybutyric acid), PHB, concentration obtained was as low as $0.21g/\ell$. Ten different complex nitrogen sources were, therefore, examined for their ability to enhance PHB synthesis when supplemented to a defined medium. Addition of tryptone, casamino acids, casein hydrolysate, or soy bean hydrolysate enhanced PHB synthesis most significantly, resulting in more than 10 times higher PHB concentration compared with that obtained in a defined medium. Furthermore, PHB yield on sucrose was also increased by more than a 10 fold by the addition of these complex nitrogen sources, which suggested that PHB might be efficiently produced by the recombinant E. coli W(pSYL105) using sucrose as a carbon source.