• Journal of Microbiology and Biotechnology
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• 제11권5호
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• pp.863-869
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• 2001

A systematic study of microbial fuel cells comprised of alkalophilic Bacillus sp. B-31 has been carried out under various operating conditions. A significant amount of electricity was generated when redox mediators were used. Among the phenothiazine-type redox dyes tested, azure A was found to be the most effective both in maintaining a high cell voltage and for the long-term operation. The maximum efficiency was and for the long-term operation. The maximum efficiency was obtained at ca. $50^{\circ}C$ giving an open circuit voltage of 0.7V. A small change in temperature did not significantly affect the cell performance, but a rapid decrease in performance was observed below $20^{\circ}C$ and above $70^{\circ}C$. It was noticeable that fuel cell efficiency and discharge pattern depended strongly on the carbon source used in the initial culture medium. Regardless of the initial carbon sources, only glucose and trehalose were utilized as substrates. Galactose, however, was not substantially utilized except when galactose was used in the initial medium. Glucose, in particular, showed $87\%$ coulombic efficiency, which was the highest value ever reported, when Bacillus sp. was cultured in a maltose-containing medium. This study demonstrates that highly efficient microbial fuel cells can be constructed with alkalophilic microorganisms by fine-tuning the operating conditions and by carefully selecting carbon sources in the initial culture medium.

• Biotechnology and Bioprocess Engineering:BBE
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• 제11권2호
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• pp.121-126
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• 2006

Saikosaponin productivity was examined in a Bupleurum falcatum L. BFHR2 hairy root culture in response to changes in the sucrose content $(2{\sim}8%)$, nitrogen content $(0{\sim}250mM\;NH_4NO_3)$, phosphate content $(0{\sim}12mM\;NaH_2PO_4)$, and the potassium content $(0{\sim}87.2 mM\; KCl)$ of the culture media. We found that the conditions for maximal saikosaponin production differed from those for optimal root growth. Highest saikosaponin yield was achieved for 8% sucrose, 62mM $NH_4NO_3$ 1.2 mM $NaH_2PO_4$, and 0.5mM KCl.

• KSBB Journal
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• 제14권2호
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• pp.241-247
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• 1999

디프테리아는 Corynebacterium diphtheriae에 의해 발생되는 호흡기 질병으로 C. diphtheriae의 exo-toxin을 불활성화 시킨 toxoid 백신을 사용하여 예방해 왔다. 현재까지 국내에서는 정치배양 방법으로 디프테리아 toxin을 생산해 왔기 때문에 생산성과 품질에 한계가 있었으며, 이를 극복하기 위해 발효조를 이용한 발효조건 최적화에 대한 연구를 수행하였다. 디프테리아 toxin을 보다 효율적을 얻기 위한 배지로서 beef antigen이 함유되어 있지 않은 casein 유래의 NZ-Case를 선택하였다. 발효조에 의한 toxin 생성은 세포성장과 함께 증가하는 growh-associated form으로 나타났다. 최대의 세포성장과 toxin 생성은 초기 pH가 7.0인 배지에서 0.22vvm의 통기와 400rpm의 교반조건에서 얻을 수 있었다. 또한 최대의 toxin 생성을 위한 최적의 iron 이온의 농도는 0.3mg/L 이었으며, morgamcphospale의 첨가에 의한 calcium-phosphate 침전이 배지 내에 iron 이온의 농도조절을 위하여 요구되었다. 면역원성을 확인하기 위한 역가시험 결과 발효조 배양에서 얻은 toxoid는 4단위에서 모든 guinea-pigs가 생존하여 2단위인 정치배양 toxin에비해 월등히 우수한 것으로 판단되었다. 결국 발효조 배양으로 toxin을 생산할 경우 부작용이 적고 수율과 생산성 및 면역원성 이 우수한 toxid의 생산이 가능하였다.

• KSBB Journal
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• 제27권2호
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• pp.97-102
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• 2012

In the present study, the biomass productivity of two green microalgae (Chlorella sp. and Dunaliella salina DCCBC2) were assessed in a 12 L tubular photobioreactor under optimum culture conditions. In the batch culture optimization process, the Chlorella sp. biomass was obtained as 1.2 g/L under atmospheric air as a sole $CO_2$ source and other culture conditions as follows: light intensity, temperature, pH, $NH_4Cl$ and $K_2HPO_4$ were 100 ${\mu}E/m^2/s$, $27^{\circ}C$, 7.0, 20.0 mM and 2.0 mM, respectively. On the other hand, 2.9 g/L of D. salina DCCBC2 biomass production was observed under the following conditions: light intensity, temperature, pH, $KNO_3$ and $K_2HPO_4$were 80 ${\mu}E/m^2/s$, $27^{\circ}C$, 8.0, 3.0 mM and 0.025 mM, respectively. At 1% $CO_2$ supply to the reactor, the Chlorella sp. production was reached 1.53 g/L with 25% increment under the same operating conditions. In addition, the maximum D. salina DCCBC2 biomass was observed as 3.40 g/L at 3% $CO_2$ concentration. Based on the aforementioned optimized conditions, the dilution rate and maximal biomass productivity of Chlorella sp. and D. salina DCCBC2 in the continuous cultivation were 0.4/d and 0.6 g/L/d and 0.6/d and 1.5 g/L/d, respectively.

• 한국미생물·생명공학회지
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• 제20권5호
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• pp.583-587
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• 1992

본 연구는 농용항생제인 kasugamycin의 생산을 위하여 S.kasugaensis의 배양조건 및 배지조성을 고찰하였다. Kasugamycin 발효시 최적 탄소원 및 질소원은 각각 soybean oil과 soybean flour였다. 배지 최적온도는 28'C, 최적 pH는 6.6이었다. 본 배양의 최적 접종 상태는 64-68시간 배양한 전배양액으로 접종하였으며, 발효중 물의 첨가는 생산성의 증가를 나타냈으나 소포제로서 silicone coil 첨가는 별 영향을 관찰할 수가 없었다.

• ALGAE
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• 제21권1호
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• pp.133-139
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• 2006

Outdoor cultivation of cyanobacterium Spirulina platensis was carried out for 40 days in a batch mode. A half concentration of the SOT based on the underground water was used as culture medium. Working volume was 5.7 tons with 0.2 m depth. During cultivation, mean water temperature, DO and light intensity were all in proper conditions for the S. platensis growth. The adjustment of pH to over 10 with Na2CO3 and addition of the 1.5% natural salt were very effective to delete contaminant organisms, Chlamydomonas moewusii and Chlorella minutissima occurred one after the other in the culture. The mean productivity of the biomass based on the dry cell weight from 14 to 25 days, after the contaminants were deleted, was 7.8 g ·m–2· d–1, which was relatively high productivity in that a half concentration of the SOT was used for the culture. Underground water used in the culture minimized contaminants invasion and addition of the 1.5% natural salt was effective to delete contaminants as well as acted as mineral supplement in outdoor cultivation of S. platensis. Harvesting using the floating activity of S. platensis was effective from mass floating in day time after overnight without agitation and illumination.

• Journal of the Korean Wood Science and Technology
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• 제33권5호통권133호
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• pp.92-98
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• 2005

This study was performed to get the basic information concerned to the optimum culture condition of Inonotus obliquus. Several solid media, PDA, MEA and Czapek-Dox, and three liquid media were adopted for the in vitro cultivation. Some main features of the fungal morphological characteristics under cultivation conditions were observed and described. Preliminary results showed that appearance of the mycelial mat, hyphal size and substrate pigmentation differed according to the media. The PDA medium was the most favorable substrate for the growth on solid culture, followed by MEA and Czapek-Dox media. Concerned to the addition of amino acids, 5 amino acids, such as alanine, alginine, isoleucine, leucine and threonine, enhanced to the mycelial growth. Isoleucine was shown the best fungal growth. An important morphological hyphal structure for the fungus, the setae, was found in abundance and diverse its shape and size. In liquid culture, fresh potato broth was the best growth stimulant of the fungus, followed by Malt extract and potato broth. Addition of yeast extract to the liquid media had improved the biomass, but not laccase production.

• KSBB Journal
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• 제21권2호
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• pp.96-102
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• 2006

H. erinaceum은 식용은 물론 각종 약리효과를 나타내어 현재 산업적으로 매우 주목되고 있는 기능성 소재들 중의 하나이다. 본 연구에서는 H. erinaceum의 기능성 소재화 연구의 일환으로, 지금까지 체계적으로 연구된 바 없는 H. erinaceum의 액체배양을 시도하고. 이 버섯 액체배양의 최적화를 수행하였다. 16종 버섯 배지의 플라스크 배양을 통해 우수 기본 배지를 선발하였고, 이의 반응표면분석에 의해 배지 및 배양조건의 최적화를 수행한 결과, 최적 배지 조성은 glucose 3%, yeast extract/peptone(1:1) 0.2%, $KH_2PO_4/MgSO_4$(1:1) 0.2%이었으며, 최적 배양조건은 $22.28^{\circ}C$, pH 5.67, 접종량 13.42%에서 얻어졌다. 이러한 최적 배지 및 배양조건하에서 얻어진 균사체량은 약 9 g/L 이었으며, 이는 기본배지에서 배양 8일 후 얻어진 최대값인 5.40 g/L에 비하면 약 1.7배 향상된 결과이었다. 하지만 H. erinaceum의 액체배양시 낮은 균체량과 비교적 느린 생육이 관찰되어 보다 높은 생산성의 향상을 위해서는 이에 적합한 새로운 형태의 fermenter의 선정 및 새로운 배양 system의 적용이 필요한 것으로 나타났다.

• 한국자원식물학회지
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• 제24권2호
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• pp.121-129
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• 2011

분자육종의 발전에 따라 좀 더 유용한 형질전환 식물체를 더 많이 얻어내기 위한 많은 형질전환 기술들이 개발되어오고 있으나 새로운 수요를 충족시키기 위한 다양한 종류의 새로운 품종들이 실시간으로 새롭게 개발되고 있으며 개발된 품종에 적합한 새로운 형질전환 기술에 대한 개발 필요성 또한 지속적으로 요구되고 있다. 카네이션(Dianthus caryophyllus L.)은 전 세계적인 주요 화훼작물 중 하나로 경제적 파급효과가 매우 큰 작물이다. 따라서 기술개발의 파급효과가 큰 카네이션을 대상으로 조직배양 및 형질전환의 효율성을 향상시키기 위하여 시장에서 주요하게 거래되고 있는 주요 품종 18종을 수집하고 이 중 조직배양을 통한 신초 분화 능력이 우수한 4개 품종 Yellow dotcom, Jakarta, Belmonte, Polar tessino 등을 선발하였다. 선발된 4개 품종에 공통으로 적용시킬 수 있는 가장 효율적인 생장조절제는 MS+Sucrose 3%+NAA 1.0 mg/L+TDZ 1.0 mg/L.이었으며 MS+Sucrose 3%+NAA 3.0 mg/L+BA 1.0 mg/L 처리는 Belmonte.에 적용 가능한 생장조절제 조합이었다. 캘러스 형성과 신초 분화에 가장 효율적인 기본 배지는 MS이었으며 탄소원으로는 Sucrose를 3%로, Phytagel 0.3%를 배지 경화제로 처리하는 것이 조직배양을 통한 재분화 식물체 획득에 가장 효과적이었다. 가장 효율적 조직배양 체계를 구축하기 위한 조직배양 부위는 줄기 부위 이었으며 이 부위를 배양재료로 사용할 경우 신초 생성율을 80.2%까지 올릴 수 있었고 배양소요 기간도 6일 정도 단축할 수 있었다.

• Mycobiology
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• 제37권2호
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• pp.114-120
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• 2009

Streptomyces albidoflavus C247 was isolated from the soil of the Gyeongsan golf course in Korea. Physiological, biochemical and 16S rDNA gene sequence analysis strongly suggested that the isolate belonged to Streptomyces albidoflavus. Preliminary screening revealed that the isolate was active against fungi and bacteria. Self-directing optimization was employed to determine the best combination of parameters such as carbon and nitrogen source, pH and temperature. Nutritional and culture conditions for the production of antibiotics by this organism under shake-flask conditions were also optimized. Maltose (5%) and soytone (5%) were found to be the best carbon and nitrogen sources for the production of antibiotics by S. albidoflavus C247. Additionally, 62.89% mycelial growth inhibition was achieved when the organism was cultured at $30^{\circ}C$ and pH 6.5. Ethyl acetate (EtOAc) was the best extraction solvent for the isolation of the antibiotics, and 100 ${mu}$/ml of EtOAc extract was found to inhibit 60.27% of the mycelial growth of Rhizoctonia solani AG2-2(IV) when the poison plate diffusion method was conducted.