• Biotechnology and Bioprocess Engineering:BBE
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• 제11권3호
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• pp.223-229
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• 2006

In this study, we have conducted kinetics and modelling studies of Centella asiatica cell growth and substrate uptake, in an attempt to evaluate cell growth for a better understanding and control of the process. In our bioreactor cultivation experiment, we observed a growth rate of 0.18/day, a value only 20% higher than was seen in the shake flask cultivation trial. However, the observed maximum cell dry weight in the shake flask, 10.5g/L, was 14% higher than was achieved in the bioreactor. Ninety seven percentage confidence was achieved via the fitting of three unstructured growth models; the Monod, Logistic, and Gompertz equations, to the cell growth data. The Monod equation adequately described cell growth in both cultures. The specific growth rate, however, was not effectively predicted with the Logistic and Gompertz equations, which resulted in deviations of up to 73 and 393%, respectively. These deviations in the Logistic and Gompertz models may be attributable to the fact that these models were developed for substrate-independent growth and fungi growth, respectively.

• KSBB Journal
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• 제6권1호
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• pp.63-68
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• 1991

본 연구에서는 L-phcn ylalaninc을 생산하는 조절기작을 상실한 영양요구성 변이주인 Corynebacterium glulamicum ATCC 21674를 이용하여 플라스크내에서의 회분식 배양시의 특성을 조사하였다. 이 균주는 회분반효시 2.1-3.4 g/I 의 phcnllalanine파 2.9-4.4 g/I 의 tyrosine을 생산하였고, 당농도가 높을 경우 생산성이 저하됨을 알 수 있었다. 또한 온도의 변화는 이들 아미노산 생산에 큰 영향을 미침이 관찰되었다. $30^{\circ}C$에사 배양하는 경우, $37^{\circ}C$에서 배양하는 것보다 훨씬 많은 아미노산이 생산되었다. 배양도즙 pH는 급격한 변화를 보였다, 이 균주는 tyrosine이 없는 최소배지에서도 자라는 것이 확인되었고, tyrosine를 과량 생성까시 함으로 보아 영양 요구 성질을 상실한 revertant로서 조전기작 상실성을 ­유지한 것으로 판단된다.

• Journal of Microbiology and Biotechnology
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• 제5권6호
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• pp.364-369
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• 1995

Effect of two-phase culture on Mentha piperita cell growth and essential oil formation was investigated using shake flask and air-lift bioreactors. LiChroprep RP-B(RP-B) addition did not impair M. piperita cell growth, but resulted in stimulated formation of essential oils and increased ratios of extracellular oil to intracellular oil formation. However, the combined use of RP-B and chitosan elicitor was not synergistic. Volumetric productivity of essential oils in RP-B treated culture using cell-recycled air-lift bioreactor was $6.9\;\mu\textrm{g}/l{\cdot}day$ which was substantially higher than that obtainable from the control. Our results demonstrate the potential of a second phase to enhance overall productivity for M. piperita cell culture.

• KSBB Journal
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• 제9권2호
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• pp.180-185
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• 1994

본 연구에서는 캘리포니아 양귀비(Eschscholtzia californica) 세포를 airlift 배양기에 적용 배양할 때 shake flask 배양보다 benzophenanthridine alkaloid의 생산성이 감소하는 원인을 찾고 이를 극복하기 위한 실험을 수행하였다. Alkaloid 생산성 감소의 주된 원인은 air sparging에 의해 $CO_2$ 및 ethylene과 같은 유용 성분의 gas가 stripping 되는 것으로 나타났으며 이 stripping 되는 gas를 다시 공급하는 gas recycle 식 airlift 배양기를 개발하였다. 이 배양기에 캘리포니아 양귀비 세포를 배양한 결과 alkaloid 함량이 일반 airlift 배양기 운전 결과보다 약 2.7배 증가하였다. 또한 이 배양기의 gas reservoir의 용량 변화에 따라 alkaloid의 생산성 및 이산화탄소의 농도가 영향을 받음을 확인하였다.

• Biotechnology and Bioprocess Engineering:BBE
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• 제3권1호
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• pp.44-47
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• 1998

Maximum cellulase production was sought by comparing the activities of the cellulases produced by different Trichoderma reesei strains and Aspergillus niger. Trichoderma reesei Rut-C30 showed higher cellulase activity than other Trichoderma reesei stains and Aspergillus niger that was isolated from soil. By optimizing the cultivation conditions during shake flask culture, higher cellulase production could be achieved. The FP(filter paper) activity of 3.7U/ml and CMCase (Carboxymethylcellulase) activity of 60U/ml were obtained from shake flask culture. When it was grown in 2.5L fermentor, where pH and DO levels are controlled, the enzyme activities were 133.35U/ml (CMCase) and 11.67U/ml(FP), respectively. Ammonium sulfate precipitation method was used to recover enzymes from fermentation broth. The dried cellulase powder showed 3074.9U/g of CMCase activity and 166.7U/g of FP activity with 83.5% CMCase recovery.

• Advances in environmental research
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• 제3권4호
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• pp.283-292
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• 2014

Iron precipitating organisms play a significant role in the formation of ferric hydroxide precipitate, which acts as strong adsorbent for toxic metal. In this respect four different iron precipitating cultures were isolated from Hutti gold mine surface winze water sample on citrate agar medium. The best isolate was screened out for metal removal study on the basis of fast visual iron precipitation. The selected isolate was identified as Enterobacter sp. based on routine biochemical tests and Biolog GN microplate results and as Enterobacter cloacae subsp. dissolvens by 16S rRNA gene sequence analysis (GenBank accession number EU429448). Influence of medium composition, medium initial pH, the influence of inoculum size, effect of various media and ferric ammonium citrate concentration were studied on metal removal in shake flask experiments. Under the optimized conditions studied, E. cloacae showed $94{\pm}2$, $95{\pm}2$ and $70{\pm}2%$ of cadmium, copper and mercury removal from a simulated waste in shake flask studies. In lab scale column reactor more than 85% of copper and mercury removal was achieved.

• Journal of Microbiology and Biotechnology
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• 제14권5호
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• pp.944-951
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• 2004

The influences of inoculum size, pH, and medium composition on mycelial growth and exopolysaccharides (EPS) production were investigated in shake flasks and in a bioreactor. The optimum inoculum size for both mycelial growth and EPS production was identified to be 10% (v/v) in shake flask cultures. The optimal initial pH for mycelial growth and EPS production in shake flask cultures were found to be 5.0 and 7.0, respectively. However, the optimal pH was 5.0 for both mycelial growth and EPS production in bioreactor cultures where the pH was regulated. The optimal mass ratio of the two major carbon sources, glucose to dextrin, was 1:4. The optimal mass ratio of the two major nitrogen sources, yeast extract to soy tone peptone, was 2:1. When 500 mg $1^{-1}$ of $MnSO_4-5H_2O$ was added to the bioreactor culture, both mycelial growth and EPS production were enhanced by approximately 10%. Under the optimized conditions, a mycelial biomass of 9.85 g $1^{-1}$ and an EPS concentration of 4.92 g $1^{-1}$ were obtained in 4 days.

• Journal of Microbiology and Biotechnology
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• 제8권3호
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• pp.208-213
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• 1998

The effect of the addition of wheat bran to the growth medium on the production of cellulolytic enzymes of Trichoderma reesei Rut C30 was studied in batch culture using shake flasks. The activity of cellulase was enhanced by the addition of wheat bran to the cellulase production medium. $KH_2PO_4$-$K_2HPO_4$ buffer was used for pH control during cellulase production. As a result, high cellulase activities were obtained in shake flask culture; a CMC (carboxymethyl cellulose) activity of 125.78 U/ml was obtained from 2% Avicel- and 3% wheat bran-containing medium and an FP (filter paper) activity of 12.85U/ml was obtained from 1% Avicel- and 5% wheat bran-containing medium after 6 days of cultivation.

• Plant Biotechnology Reports
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• 제2권2호
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• pp.133-136
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• 2008

Cell cultures of Commiphora wightii (Arnott.) Bhandari were grown in shake flasks and a bioreactor and an increase in guggulsterone accumulation up to $18{\mu}g\;l^{-1}$ was recorded in cells grown in the production medium containing a combination of sucrose:glucose (4% total), precursors (phenylalanine, pyruvic acid, xylose, and sodium acetate), morphactin, and 2iP. A yield of $10g\;l^{-1}$ biomass and ${\sim}200{\mu}g\;l^{-1}$ guggulsterone was recorded in a 3-l flask and in a 2-l stirred tank bioreactor compared with 6.6 g biomass and $67{\mu}g\;l^{-1}$ guggulsterone in 250-ml flasks. Increased vessel size was correlated with increased biomass and guggulsterone accumulation. 2iP alone was not effective for biomass and guggulsterone accumulation in cell cultures of C. wightii.

• KSBB Journal
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• 제8권3호
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• pp.295-299
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• 1993

Shake flask를 사용하여 M. piperita 세포의 현탁 배양에서의 fungal elicitor, pluronic F-B8, methylcellulose의 영향에 대하여 연구하였다. 그 결과 Rhodotorula rubra라는 균주에서 추출한 fungalelicitor를 처리하여 약 2배 정도 박하정유 생산의 증가를 관찰하였고 100 rpm의 교반속도에서 낮은 농도의 Pluronic F-68, methylcellulose 첨가에 의해 박하세포의 성장이 증진되었다.