• 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.

• Journal of The Korean Society of Agricultural Engineers
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• v.48 no.7
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• pp.65-72
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• 2006

Event mean concentration (EMC) of nitrogen (N) and phosphorus (P) is primary information for non-point source pollution assessment of a watershed. The EMCs for various types of agriculture such as dairy and crop farming under different climate and geologic conditions are not fully investigated. A diary- and cropfarming complex agricultural watershed in Piedmont region in Maryland, USA has been monitored for 10 years as a section 319 national monitoring program of US EPA. Dairy manure was the main source of fertilizer for crop farming in this watershed. Observed mean concentrations of N and P for each event were analyzed. Distribution of EMCs for N and P showed a wide range of variations. Representative EMCs of T-N and $NO_{3}-N$ tended to be higher than those reported for other agricultural watersheds. This study confirmed that site-specific EMC information for various agricultural practices is required for better assessment of non-point source pollution using EMC method.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2003.05b
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• pp.261-264
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• 2003

We try to distribute air pollution sources at target area. The complex method is used to distribute air pollution sources. Most of people, However, want to simple indicator as standard for express air pollution source. In many area, air pollution is caused by different types of sources. The general type is point source, such as tall stack of power plants and oil refineries stacks. A second type is areal source, such as local industry and transportation. In this aspect, the ratio of sulfur dioxide to nitrogen oxides (RSN =SO$_2$/NOx)is an indicator of air pollution source. the role of this ratio is to show the characteristics at target area of the relationship the point and the areal source. (omitted)

• Journal of Microbiology and Biotechnology
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• v.18 no.1
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• pp.124-127
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• 2008

The behavior of Penicillium camembertii and Geotrichum candidum growing in submerged pure cultures on simple (glutamate) or complex (peptones) substrates as nitrogen and carbon sources and lactate as a second carbon source was examined. Similar to the behavior previously recorded on a simple substrate (glutamate), a clear differentiation between the carbon source and the energy source was also shown on peptones and lactate during P. camembertii growth, since throughout growth, lactate was only dissimilated, viz., used for energy supply by oxidation into $CO_2$, whereas peptides and amino acids from peptones were used for carbon (and nitrogen) assimilation. Because of its deaminating activity, G candidum preferred peptides and amino acids to lactate as energy sources, in addition to being assimilated as carbon and nitrogen sources. From this, on peptones and lactate, G candidum grew faster than P. camembertii (0.19 and 0.08 g/l/h, respectively) by assimilating the most readily utilizable peptides and amino acids; however, owing to its lower proteolytic activity, the maximum biomass was lower than that of P. camembertii (3.7 and 5.5 g/l, respectively), for which continuous proteolysis and assimilation of peptides were shown.

• Bulletin of the Korean Chemical Society
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• v.9 no.5
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• pp.292-295
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• 1988

Macrocyclic ligands have been studies as cation carriers in a bulk liquid membrane system. $Cu^{2+}$ has been transported using nitrogen substituted macrocycles as carriers and several transition metal ions($M^{n+}\;=\;Mn^{2+},\;Co^{2+},\;Ni^{2+},\;Cd^{2+},\;Pb^{2+}\;and\;Ag^{+}$) have been transported using $DBN_3O_2,\;DBN_2O_2,\;Me_6N_414C4$ and DA18C6 as carriers in a bulk liquid membrane system. Competitive $Cu^{2+}-M2^+$ transport studies have also been carried out for the same system. In single cation transport experiments, the best macrocyclic ligand for transport is a ligand that gives a moderately stable rather than very stable complex in the extraction. However, when both cations are present in the source phase, the cation which forms the most stable complex with carrier is favored in transport over other cations. Generally, the nitrogen substiituted macrocycles transport $Cu^{2+}$ selectively over $Mn^+$. Ligand structure, equilibrium constant (or stability constant) for complex formation, source phase pH and carrier concentration are also important parameters in transport experiments.

• 한국생물공학회:학술대회논문집
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• 2000.04a
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• pp.227-230
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• 2000

Batch cultivations of Anaerobiospirillum succiniciproducens have been systematically studied for the economical production of succinic acid from wood hydrolysate with corn steep liquor(CSL) as a nitrogen source. CSL was found to be an alternative complex nitrogen source for A. succiniciproducens when glucose and wood hydrolysate were used as carbon sources. Compared with polypeptone and/or yeast extract, CSL had similar effects on fermentation performance such as succinic acid yield and a ratio of succinic acid to acetic acid in the fermentation of wood hydrolysate as well as glucose. This means that succinic acid can be produced more economically from wood hydrolysate and CSL than relatively expensive carbon and nitrogen sources. Besides its low cost, the alternative medium served as a green technology for succinic acid production because it gives a net-zero effect on global warming.

• Mycobiology
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• v.39 no.1
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• pp.1-6
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• 2011

Isolates of Ophiocordyceps heteropoda (Kobayasi) collected from Mt. Halla on Jeju-do, Korea were tested for mycelial growth on different agar media and in the presence of different carbon and nitrogen sources. Similarly, isolates were also incubated at different temperatures as well as under continuous light and dark conditions. Growth was better on Hamada agar, basal medium, and malt-yeast agar, but poor on Czapek-Dox agar. Different carbon sources such as dextrin, saccharose, starch, lactose, maltose, fructose, and dextrose resulted in better growth. Complex organic nitrogen sources such as yeast extract and peptone revealed the most effective growth. Mycelial growth was best at $25^{\circ}C$. The growth rate was faster in the dark than the light, but mycelial density was less compact in the dark.

• 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 Microbiology
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• v.40 no.2
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• pp.100-103
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• 2004

The culture condition and medium composition for the enhanced mycelial growth of Inonotus mikadoi IMSNU 32058 were investigated. The optimal temperature and pH for the mycelial growth were $27^{\circ}C$ and pH 4.5, respectively. Among the complex media tested, the malt extract medium and Phellinus igniarius medium were very good for mycelial growth of I. mikadoi. When Czapek-Dox medium was used as a minimal medium for cultivation of mycelia, xylose, raffinose and carboxymethyl cellulose were very excellent as a carbon and energy source. With respect to carbohydrate, sucrose and glucose were very good carbon sources. In general, organic complex nitrogen sources were better than other inorganic ones. As the organic complex nitrogen sources tested, yeast extract, soytone, proteose peptone and bacto peptone were the best as a source of organic nitrogen. When ammonium sulfate as an inorganic source of nitrogen was used, the enhanced mycelial growth was shown. p-Aminobenzoic acid was proved to be most appropriate source of vitamin. After the mycelia of I. mikadoi was cultivated at $27^{\circ}C$ for 5 days in MEM broth (pH 4.5), the activities of both exomycelial and endo-mycelial enzymes were determined. Among endomycelial enzymes assayed, the specific activity of laccase was much higher than those of other enzymes. When the fungus was grown in MEM broth, exomycelial specific enzyme activity of laccase was comparatively high. However, little or no enzyme activities of protease, chitinase and lipase were found.

• Microbiology and Biotechnology Letters
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• v.22 no.6
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• pp.614-620
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• 1994

The effects of growth temperature and nutritional components on the synthesis of poly-3-hydroxybutyric acid, PHB, by filamentation-suppressed recombinant Escherichia coli XL1-Blue (pSYL107) were studied. After culturing XL1-Blue(pSYL107) for 48 hours in complex medium at 30$\circ$C, 7Al g/l of PHB could be obtained with the PHB content and PHB yield of 82% and 0.371 g PHB/g glucose, respectively. Lower concentration of PHB(3.2 g/l) was obtained when cultu- red at 37$\circ$C, which seemed to be due to the instability of this strain having amplified FtsZ activity. The PHB concentration of 3.75 g/l was obtained after culturing 60 hours in R medium supplemen- ted with 20 g/l glucose at 30$\circ$C, which was more than twice higher than that obtained with XL1-Blue(pSYL105). This suggested that the enhancement of PHB synthesis by suppressing filamenta- tion was more significant in a defined medium than complex medium. PHB synthesis could be further enhanced by supplementing a small amount of various complex nitrogen sources. When 5 g/l of beef extract was added to a defined medium, PHB concentration, PHB content, and PHB yield obtained after 60 hours of cultivation at 30$\circ$C were 7.46 g/l, 86%, and 0.375 g PHB/g glucose,respectively.