• Journal of Mushroom
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• v.2 no.1
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• pp.21-27
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• 2004

Distribution and in vitro growth characteristics of entomopathogenic Paecilomyces species were studied based on the specimens and isolates deposited in Entomopathogenic Fungal Culture Collection (EFCC), Kangwon National University, Chuncheon, Korea. Paecilomyces species were frequently collected from different mountains and valleys and were almost distributed uniformly. Collection period of Paecilomyces species ranged from July to September, with most of the collections at the end of September. P. tenuipes was mostly collected one among different Paecilomyces species. The optimum medium for mycelial growth of P. tenuipes was PDA, whereas in other media such as SDAY and HMA also produced similar growth. The optimum temperature and pH levels were $25^{\circ}C$ and 6.0~7.0, respectively. Best carbon and nitrogen sources were dextrose and tryptone, respectively, while $KH_2PO_4$ was the best mineral source for mycelial growth. Highest mycelial growth was observed when the C/N ratio was 20:1.

• Journal of Life Science
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• v.22 no.2
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• pp.200-208
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• 2012

The characteristics of mycelium growth of Sparassis crispa KGFS08 and KFRI746 in liquid culture were investigated. The optimum growth of the mycelium of S. crispa was observed in the KTM medium. The best carbon source was starch. In terms of nitrogen sources, tryptone affected mycelial growth in the liquid culture. The optimal culture conditions were pH 4.0-5.0 in STK medium [3% (w/v) starch, 0.3% (w/v) tryptone, 0.1% (w/v) $KH_2PO_4$, and 0.1% (w/v) folic acid].

• Transactions of the Korean hydrogen and new energy society
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• v.21 no.2
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• pp.136-142
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• 2010

Photobiological $H_2$ production was compared using purple non-sulfur bacteria Rhodobacter sphaeroides KD131 in the medium containing various organic acids as the carbon source and electron doner under illumination of $110\;W/m^2$ using halogen lamp at $30^{\circ}C$. The organic acids used were 0~120 mM acetate, butyrate, lactate and malate. Initial pH 7.0 and cell concentration 1.0 at 660nm were increased to pH 8 and 4.4~5.1, respectively during 24hrs of photo-fermentation when lactate and malate were used. However, acetate and butyrate increased pH to 9 and cell concentration to 3.2~3.9 of malate at the same experimental conditions. Optimum ranges of organic acids concentration and carbon/nitrogen ratio were 30~60 mM and 10~20, respectively. When malate was used as the substrate, maximum $H_2$ production 1.1 ml $H_2$/ml broth, which is equivalent to 1.97 mol $H_2$/mol malate was observed.

• Journal of Korean Society on Water Environment
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• v.21 no.6
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• pp.643-650
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• 2005

In order to treat leachate from aged landfill site effectively, removal of biologically recalcitrant organic matter and denitrification efficiency were evaluated through the combination of $H_2O_2/O_3$ AOP pretreatment process and UASB process. The results can be summarized as follows. In case of leachate having low COD/N ratio from aged landfill site, it is possible to increase available COD for denitrification in nitrate utilizing denitrification and nitrite utilizing denitrification both by enhancing biodegradability of recalcitrant organic matter as applying $H_2O_2/O_3$ AOP to pretreatment process. In this experiment, it is found that available COD for denitrification can be increased to 1.0 and 0.4 g/day, respectively. Comparison has been made between requiring COD and available COD for denitrification in each experimental stages. It is expected that high rate of denitrification can be achieved with leachate from young landfill site because higher amount of available COD for denotrification is present in the leachate than the amount of requiring COD for denitrification. Especially, In leachate from aged landfill site with low COD/N ratio, it can be concluded that denitrification using nitrite nitrogen can enhance overall denitrification performance efficiently because denitrification using nitrite nitrogen requires less amount of carbon source than denitrification using nitrate nitrogen. Comparing the biogas production rate and nitrogen content of biogas under the condition of same amount of nitrate and nitrite addition, biogas production and nitrogen content of biogas are increased during denitrification after $H_2O_2/O_3$ AOP pretreatment process. Therefore, it can be confirmed that COD/N ratio in the leachate is increased. Applying $H_2O_2/O_3$ AOP as pretreatment system of landfill leachate seems to have little economic benefit because it requires additional carbon source to denitrify ammonia nitrogen in leachate coming from aged landfill site. However, it is possible to apply this pretreatment process to leachate from old landfill site in view of AOP process can achieve removal of biologically recalcitrant organic matter and increase of available COD for denitrification simultaneously.

• KSBB Journal
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• v.16 no.6
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• pp.632-637
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• 2001

The cells obtained from diesel contaminated site were tested for diesel degradation by culturing them on the culture medium that contained diesel as the only carbon source. Two strains that grew well in the culture media were separated: one formed white colony and another strain formed yellow colony. When they were cultured together, much higher diesel degradation was obtained compares to that of individual cell culture. Mixed culture of white and yellow colony forming strains grew well with 1%(v/v) diesel and the addition of growth nutrients increased the diesel degradation. Additional nitrogen source was efficient for higher diesel degradation (over 90%) when it was compared with that without nitrogen source. When mixed culture of white and yellow colony forming cells were applied to the soil column system contaminated by diesel, 30 mL/min of air flow rate was found to be sufficient to degrade diesel oil. The diesel degradation did not increase noticeably at higher flow rate. The addition of nitrogen source resulted in the increase in diesel degradability.

• 한국생물공학회:학술대회논문집
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• 2005.04a
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• pp.175-180
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• 2005

In this study, we investigated the optimal medium composition for bacterial cellulose (BC) production by Gluconacetobacter sp. RKY5. Among the various kinds of carbon sources, glycerol was the most efficient as a sole carbon source and its optimal concentration for BC production was 15 g/L. The optimal concentration of yeast extract as a nitrogen source for BC production was found to be 8 g/L. $K_{2}HPO_{4}$ and acetic acid were selected respectively as a phosphate source and a secondary substrate, and both optimal concentrations were 3 g/L. The amount of produced BC was 4.59 g/L in a static culture and 6.5 g/L in a shaking culture condition with 150 rpm. These values were 2.1 and 2.7 times higher than those in a static (2.16 g/L) and a shaking (2.41 g/L) cultures using HS medium generally used for BC production.

• Korean Journal of Microbiology
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• v.45 no.1
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• pp.69-73
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• 2009

Proteases are degradative enzymes which hydrolyze a peptide bond between amino acids and they are abundantly applied to commercial field. In order to investigate optimal medium compositions of carbon and nitrogen source for enzyme production, modified STY medium containing 0.15% yeast extract were used as basal medium. When galactose was used as carbon source, enzyme activity showed 1.3 higher than that of glucose. For nitrogen source addition of casamino acids to basal medium in place of tryptone showed lowest activity, whereas addition of malt extract showed maximal activity. The optimum temperature and pH of extracellular protease were found to be $35^{\circ}C$ an pH 8.5.

• 한국생물공학회:학술대회논문집
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• 2000.04a
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• pp.259-262
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• 2000

The production of pullulan by Aureobasidium pullulans HP-2001 was investigated under various ratios of glucose as carbon source and yeast extract as the nitrogen source, Highest conversion rate (productivity) of glucose to pullulan was 40.0% when concentrations of glucose and yeast extract were 5% and 0.15%, respectively. Maximal production of pullulan was 29.3g/1 when the concentration of glucose was 8%(w/v) and that of yeast extract was 40:1. On basis of the result that production of pullulan was found in a medium which concentration of glucose as carbon source was up to 20%(w/v), Aureobasidium pullulans HP-2001 seemed to overcome the catabolite repression. Conversion rate of pullulan from 20%(w/v) of glucose was 11.1%.

• Microbiology and Biotechnology Letters
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• v.2 no.2
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• pp.95-101
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• 1974

Studies on the optimum conditions of acid hydrolysis of sweet potato starch cake and its utilization on the production of Saccharomyces cerevisiae as a carbon source were conducted and the results showed as follows; 1.The highest hydrolysis rate, 62.7 ％ of the reducing sugar based on the weight of the dry matter, was obtained when the starch cake was hydrolyzed with 1.0％ of hydrochloric acid at 2.0 kg/$\textrm{cm}^2$ for 30 minutes. 2. But the yeast grew most favorably on the hydrolyzate obtained by treating the starch cake with 0.5％ of hydrochloric acid at 2.0 kg/$\textrm{cm}^2$ for 10 minutes. Reducing sugar content of hydrolyzate was 51.4％. 3. The optimum pH of the culture medium was 7.0, Cell growth reached to the maximum at 36 hours of cultivation time. 4. According to the vitamin requirement tests, Ca-pantothenate was found to be a promoting factor for the growth of the yeast cells. 5. "Gluten acid hydrolyzate" was most effective to the cell growth when added to the medium at the concentration of 0.1％ as a nitrogen source. 6. Sacch. cerevisiae could assimilate the sugars in the hydrolyzate about 89.1％, and the yields of the yeast cells showed 23.2mg/ml of culture medium.

• The Korean Journal of Mycology
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• v.12 no.1
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• pp.15-19
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• 1984

Some factors affecting mycelial growth of Pleurotus sajor-caju and P. ostreatus. were investigated. The optimal temperature and pH of the medium for mycelial growth of both the species were $25^{\circ}C$ to $30^{\circ}C$, and 5 to 6, respectively. The effect of carbon and nitrogen sources on mycelial growth of the species was studied using modified Waksman's special medium as the basal medium. Generally, the disaccharides and polysaccharides showed good effect for mycelial growth of P. sajor-caju, and the polysaccharides were superior to the other classes of carbon sources for mycelial growth of P. ostreatus. Generally the organic nitrogen compounds showed good mycelial growth of both the species. The mycelial growth of the species were favored by the ammonium nitrogen more than by the nitrate nitrogen source. Asparagine was superior to the other kinds of amino acid. Six percentage of glucose and 0.6% ammonium tartarate was optimum for mycelial growth of P. sajor-caju whereas the optimum concentration for the P. ostreatut was 4% glucose and 0.4% ammonium tatarate.