• Biotechnology and Bioprocess Engineering:BBE
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• 제7권2호
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• pp.89-94
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• 2002

The continuous production of citric acid from dairy wastewater was investigated using calcium-alginate immobilized Asrergillus niger ATCC 9142. The citric acid productivity and yield were strongly affected by the culture conditions. The optimal pH, temperature, and dilution rate were 3.0, 30$^{\circ}C$, and 0.025 h$\^$-1/, respectively. Under optimal culture conditions, the maximum productivity, concentration, and yield of citric acid produced by the calcium-alginate immobilized Aspergillus niger were 160 mg L$\^$-1/ h$\^$-1/, 4.5 g/L, and 70.3%, respectively, The culture was continuously perfored for 20 days without any apparent loss in citric acid productivity. Conversely, under the same conditions with a batch shake-flask culture, the maximum productivity, citric acid concentration, and yield were only 63.3 mg L$\^$-1/h$\^$-1/, 4.7 g/L and 51.4%, respectively, Therefore, the results suggest that the bioreactor used in this study could be potentially used for continuous citric acid production from dairy wastewater by applying calcium-alginate immobilized Aspergillus niger.

• 한국식품저장유통학회지
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• 제11권1호
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• pp.111-116
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• 2004

Monascus rubber KCTC 6122를 이용하여 액체 배양을 통한 실험균의 적색 색소의 생산을 위한 배양 조건의 최적화에 관한 결과는 다음과 같다. 실험 균주가 생산하는 적색색소의 최적 배양 조건은 탄소원으로 rice powder 4% 첨가, 질소원으로 NaN0$_3$ 0.2%, 인산염으로 $Na_2$HPO$_4$의 농도가 0.3%, MgSO$_4$의 농도가 0.15%일 때 가장 높은 적색 색소 생성을 나타내었다. 배양 온도는 3$0^{\circ}C$, 초기 pH가 6.5, 진탕속도를 150 rpm, 배양 시간 8일 일 때 적색 색소의 생성능이 흡광도 70.29로 가장 우수하였다.

• Journal of Applied Biological Chemistry
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• 제54권3호
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• pp.153-158
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• 2011

본 연구에서는 Bacillus subtilis JK-1의 생물계면활성제 생산을 위한 배양 특성을 조사하기 위하여 다양한 배양 온도와 배지의 pH, NaCl 농도에 따른 균주의 생장과 배양액의 pH, crude 생물계면활성제의 표면장력을 배양 시간대별로 측정하였다. B. subtilis JK-1은 $15-45^{\circ}C$와 pH 6-10, 0-10% (w/v) NaCl 농도의 환경에서 생장과 생물계면활성제 생산이 가능하였으며, 배양액의 pH는 중성 또는 약알칼리성으로 점차 변화 하였다. 생물계면활성제 생산은 pH 7.0의 초기 배지에서 $35^{\circ}C$, 48시간 동안 배양했을 때 최대였으며, 이 때의 표면장력은 24.0mN/m이었다. 그리고 배지 내 NaCl 농도가 0% (w/v)에서 10% (w/v)로 증가할수록 균주 생육도는 감소하였고, 최종 배양액의 pH는 약알칼리성에서 산성으로 변화하였으며, 표면장력 값은 증가하였다.

• 펄프종이기술
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• 제35권1호
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• pp.34-40
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• 2003

This study was carried out to select the useful bacteria which secret extracellula enzymes for enzymatic deinking agent of old newspaper. CMCase, FPase and xylanase activities of the bacteria liquid culture were measured at optimal growth conditions. Clear zone test was checked on the solid culture. The results of this study were as follow: Eight strains of 28 bacteria isolated from a paper mill soil ground were shown strong CMCase and xylanase activity with the clear zone test. The optimal pH and temperature for culture growth were 6~8 and 26~$34^{\circ}C$, respectively and optimal culture period were less than 60 hours. Based on CMCase, FPase and xylanase activity, strain No. 18, 21, 22 and 28 which were relatively higher than the other strains, were selected for further enzymatic deinking research.

• Journal of Microbiology and Biotechnology
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• 제7권5호
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• pp.318-322
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• 1997

In order to isolate a microorganism having preferential degradation of D-carnitine from DL-carnitine, a bacterium assimilating D-carnitine as a sole carbon and energy source was isolated from soil by enrichment culture and partially identified as Enterobacter sp. Also, a mutant having lessened L-carnitine decomposition rates was selected with nitrosoguanidine mutagenesis, which led to decrease the specific activities of carnitine dehydrogenase (7.6-fold) and ${\beta}$-hydroxybutyrate dehydrogenase (9.5-fold) as compared to the wild strain. Meanwhile, optimal culture conditions for optical resolution of DL-carnitine were investigated. Under optimal conditions, 3.53 g/l L-carnitine was obtained from 20 g/l DL-carnitine, which corresponded to 35.3% L-carnitine yield and 97.9% optical purity.

• 한국식품저장유통학회지
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• 제13권2호
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• pp.192-197
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• 2006

Monascus purpureus MMK2를 이용하여 황색색소 생산을 위한 배양 조건의 최적화에 관한 결과는 다음과 같다. 실험 균주가 생산하는 황색색소의 최적 배양 조건은 탄소원으로 wheat flour 3.0% 첨가, 질소원으로 $NaNO_3$ 0.15%, 인산염으로 $Na_2HPO_4\;12H_2O$의 농도가 0.25% 및 $MgSO_4\;7H_2O$의 농도가 0.15%일 때 가장 높은 황색색소 생성을 나타내었다. 배양 온도는 $30^{\circ}C$, 초기 PH가 6.5 및 배양 시간 7일 일 때 황색색소의 생성능이 28.91 unit로 가장 우수하였다.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2000년도 추계학술발표대회 및 bio-venture fair
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• pp.317-320
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• 2000

The optimal temperature and pH for both mycelial growth and exe-biopolymer production by Cordyceps millitaris in shake flask culture were found to be $20^{\circ}C$ and 6.0, respectively. Sucrose (4%) and corn steep powder (1%) were the most suitable carbon and nitrogen source for mycelial growth and exo-biopolymer production. The maximum specific growth rate $(0.142h^{-1})$ was achieved when sucrose was used as the sole carbon source. Exo-biopolymer production was increased with the increase in C/N molar ratio concentration, probably due to the facilitated carbon uptake. Under the optimal culture conditions, the maximum mycelial growth exe-biopolymer concentration were reached to around 13.3 g dry cell weigh/l and 3.33 g/l, respectively.

• 생명과학회지
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• 제6권2호
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• pp.79-86
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• 1996

A bacterium producing pullulanase was from soil, and was identified Bacillus cereus and named as Bacillus cereus JK36. The optimal culture conditions for the efficident production of pullulanase from B. cereus JK36 was obtained by cultivating with the medium composed of 1% pullulan, 1% teast extract, 1% bactopeptone, 0.1% NaH$_{2}$PO$_{4}$, 2H$_{2}$O, 0.02% MgSO$_{4}$\ulcorner7H$_{2}$O at 40$\circ$C, initial pH 6.5 for 70 hours. Using the culture supernatant as crude enzyme, the optimal pH and temperature of the pullulanase of this strain were 6.5 and 50$\circ$C. In effect of pH and temperature on the stability of the enzyme, the enzyme was stable in the range of pH6.0$\sim$9.5 and up to 40$\circ$C, respectively. The hydrolysis product on pullulan was mainly maltotriose.

• KSBB Journal
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• 제6권4호
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• pp.363-368
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• 1991

PVA degrading bacteria were isolated from water system, and identified as Pseudomonas cepacia and Pseudmonas pseudomallei, which were named as Pseudomonas sp. G5Y and Pseudomonas sp. PW. It was found out that those two kinds of bacteria have a symbiotic relationship to degrade PVA. For the mixed culture of these bacteria, the optimal conditions of pH, temperature, nitrogen source, and polymerization degree of PVA were found to be 7.5, $35^{\circ}C$, ammonium sulfate, and 500, respectively. Also, the growth of these bacteria was promoted by trace elements such as vitamin B1, B12, pyridoxine, and p-aminobenzoate, respectively. The specific growth rate of mixed bacteria was inhibited when the concentration of PVA was more than 20g/l. The substrate inhibition kinetics of the mixed culture was $${\mu}=\frac{0.065S}{2.56+S+(S^2/156}hr^{-1}$

• 한국균학회지
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• 제49권1호
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• pp.45-55
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• 2021

본 연구에서는 A. microsporus의 최적 배양 조건을 구명하고자 하였다. A. microsporus 균사체의 효율적 배양을 위한 조건은 최적 배양 온도 25℃, pH 5.0, 탄소원 soluble starch 1%, 유기질소원 malt extract 1%, 무기질소원 NH₄H₂PO₄ 0.1%, 아미노산 asparatic acid 0.1% 조건으로 선발되었고 유기산, 무기염류 첨가 시 균사생육이 저조해지는 영향을 주어 선발되지 않았다. 새로이 SMNA로 명명한 A. microsporus의 최적 배지는 기존의 PDA 배지 상에서 배양한 결과와 비교하였을 때, 균사의 생육이 균일하고 안정적이며 배양 기간을 15.1% 정도 단축하는 효과가 있었다. SMNA 배지는 추후 A. microsporus의 균사체 배양 방법에 널리 활용될 수 있을 것으로 판단된다.