• Journal of Microbiology and Biotechnology
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• 제18권11호
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• pp.1773-1784
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• 2008

Effects of various industrially important carbon sources (glucose, sucrose, xylose, gluconate, and glycerol) on shikimic acid (SA) biosynthesis in Escherichia coli were investigated to gain new insight into the metabolic capability for overproducing SA. At the outset, constraints-based flux analysis using the genome-scale in silico model of E. coli was conducted to quantify the theoretical maximum SA yield. The corresponding flux distributions fueled by different carbon sources under investigation were compared with respect to theoretical yield and energy utilization, thereby identifying the indispensable pathways for achieving optimal SA production on each carbon source. Subsequently, a shikimate-kinase-deficient E. coli mutant was developed by blocking the aromatic amino acid pathway, and the production of SA on various carbon sources was experimentally examined during 51 batch culture. As a result, the highest production rate, 1.92 mmol SA/h, was obtained when glucose was utilized as a carbon source, whereas the efficient SA production from glycerol was obtained with the highest yield, 0.21 mol SA formed per mol carbon atom of carbon source consumed. The current strain can be further improved to satisfy the theoretically achievable SA production that was predicted by in silico analysis.

• KSBB Journal
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• 제10권2호
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• pp.221-229
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• 1995

본 연구에 서는 Zoogloea ramigera에 의한 zooglan 생산에서 탄소원의 영향에 대한 연구를 수행하였다. 탄소원의 농도를 기존의 연구에셔 사용된 $25g/\ell$ 보다 높은 $45g/\ell$ 를 사용한 경우에도 zooglan을 효과 적으로 생산함으로써 유청을 희석시키지 않고 그대로 zooglan 생산에 사용할 수 있는 가능성을 확인하였다. 탄소원이 lactose인 발효배양의 경우 zooglan 생 산량 및 정도가 가장 켰고, glucose, galactose, su­c crose 순이었다. 정제된 zooglan용액(5g/P)의 점도 는 lactose 기질로 생산된 zooglan의 경우 가장 큰 값을 보였고 glucose, galactose 기질의 경우가 가약간 작았으며 sucrose 기질의 경우는 상당히 낮은 값을 보였다. Lactose로의 배양시 발효액 에 상탕량 의 glucose와 galactose가 존재하였지만 이 균주는 세포외로 ${\beta}$-galactosidase를 분비하기보다는 세포내 에 존재한 ${\beta}$-galactosidase에 의해 lactose를 분해 하고 다음 대사과정으로 들어가지 못한 과영의 단당 들이 세포 밖으로 배출된 것으로 판단된다.

• Biotechnology and Bioprocess Engineering:BBE
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• 제7권3호
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• pp.171-177
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• 2002

The metabolic flux pattern for L-histidine production was analyzed when glucose and/or acetate were used as carbon sources. Total L-histidine production was enhanced when mixed substrate (glucose and acetate) was used, compared wish that when either glucose or acetate was used as the sole carbon source. Theoretical maximum carbon fluxes through the main pathways for L-histldine production, cell growth, and ATP consumption for cell maintenance were obtained by the linear programming (LP) method. By comparison of the theoretical maximum carbon fluxes tilth actual ones, it was found that a large amount of glucose was actually used for maintenance of cell viability. On the other hand, acetate was used for cell growth. After depletion of acetate in the mixed substrate culture, the flux for glucose to L-histldine synthesis was markedly enhanced. A strategy for effective L-histidine production using both carbon sources was proposed.

• Journal of Microbiology
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• 제43권1호
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• pp.44-48
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• 2005

In our previous study, the first structural gene (GGTI) encoding ${\gamma}-glutamyl$ transpeptidase was cloned and characterized from the fission yeast Schizosaccharomyces pombe, and its transcription, using the GGTI-lacZ fusion gene, containing the 1,085 bp upstream region from the translational initiation point, was found to be enhanced by sodium nitroprusside and L-buthionine-(S,R)-sulfoximine (BSO). In the present work, regulation of the GGTI gene was further elucidated. Non-fermentable carbon sources, such as acetate and ethanol, markedly enhanced the synthesis of ${beta}-galactosidase$ from the GGTI-lacZ fusion gene. However, its induction by non-fermentable carbon sources appeared to be independent of the presence of the Pap1 protein. Nitrogen starvation also gave rise to induction of GGTI gene expression in a Pap1-independent manner. The three additional fusion plasmids, carrying 754, 421 and 156 bp regions, were constructed. The sequence responsible for the induction by non-fermentable carbon sources and nitrogen starvation was identified to exist within a -421 bp region of the GGTI gene. Taken together, the S. pombe GGTI gene is regulated by non-fermentable carbon sources and nitrogen starvation.

• Carbon letters
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• 제14권3호
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• pp.145-151
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• 2013

Graphene is a fascinating material with excellent electrical, optical, mechanical, and chemical properties. Remarkable progress has been made in the development of methods for synthesizing large-area, high-quality graphene. Recently, the chemical vapor deposition method has opened up the possibility of using graphene for electronic devices and other applications. This review covers simple and inexpensive methods to grow graphene using polymers as solid carbon sources; which do not require an additional process to transfer graphene from the growth substrate to the receiver substrate.

• The Plant Pathology Journal
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• 제24권2호
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• pp.164-170
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• 2008

Carbon utilization by Chryseobacterium strain KJ1R5 was studied to enhance its biocontrol activity against Phytophthora capsid. Chryseobacterium strain KJ1R5 has previously been shown to control Phytophthora blight of pepper (Capsicum annuum L.). Strain KJ1R5 could utilize carbon sources such as L-arabinose, D-cellobiose, ${\beta}-lactose$ and D-galactose well. P. capsici could utilize D-glucose well, showing the absorbencies ranged from 0.577 to 0.767 at 600nm. When 2% L-arabinose, which could only be utilized by the bio-control strain KJ1R5, was amended into the bacterial suspension, the efficacy of biological control increased. Among the amendments of various carbon sources into bacterial suspension, L-arabinose and D-(+)-glucose significantly enhanced biological control activity, resulting in a reduction of disease incidence to 6.9%, compared to 21.9% for the strain KJ1R5 alone and 81.3% for P. capsici inoculation alone, indicating that amendment with specific carbon sources could increase the biological control activity.

• 한국물환경학회지
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• 제28권5호
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• pp.663-668
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• 2012

The feasibility of enhancing biological nutrient removal from an industrial wastewater was tested with food waste leachate and sugar liquid waste as external carbon sources. Long term influences of adding external carbon sources were investigated to see how the biological nutrient removal process worked in terms of the removal efficiency. The addition of the external carbons led to a significant improvement in the removal efficiency of nutrients: from 49% to approximately 76% for nitrogen and from 64% to around 80% for phosphorus. Approximately, 20% of the removal nitrogen was synthesized into biomass, while the remaining 80% was denitrified. Though the addition of external carbon sources improved nutrient removal, it also increased the waste sludge production substantially. The optimal observed BOD/TN ratio, based on nitrogen removal and sludge production, was around 4.0 in this study.

• 한국환경과학회지
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• 제32권9호
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• pp.647-657
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• 2023

The study analyzes the forest status of each local government for Korean forests and believes that it can be used as basic data for setting the direction pursued by each local government. The study took into account the fact that the forest rate in Korea was 63.5%, because it was judged that the higher the proportion of forest area, the more important it was to use the characteristics of forests. The characteristics of forests were analyzed based on four factors in 12 factors to identify the location of the ground body by dividing seven types. In addition, basic information on carbon absorption sources was provided by grasping the ability of carbon absorption sources per year through the amount of forest resources to be analyzed. In addition, as a result of analyzing the characteristics of the weather for the promotion of carbon absorption sources, the flat area on the side of Gangneung Mountain was a warm forest with a warm index of 106.0.

• 인간식물환경학회지
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• 제24권5호
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• pp.461-468
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• 2021

Background and objective: Particulate matter (PM) has a serious impact on health. Recently, studies are conducted to reduce PM in an environmentally friendly way using plants. This study investigated the physiological responses of plants and their ability to remove PM by continuously spraying different PM sources (loam, fly ash, carbon black) to four native plant species, such as Iris sanguinea, Pteris multifida, Vitis coignetiae, and Viburnum odoratissimum var. awabuki. Methods: The four plant species were randomly placed in four chambers, and 0.1 g of different PM was injected into each chamber twice a week. We measured chlorophyll, carotenoid, chlorophyll fluorescence (Fv/Fm), total leaf area, amount of leaf wax, PM10 (sPM10) and PM2.5 (sPM2.5) on the leaf surface, and PM10 (wPM10) and PM2.5 (wPM2.5) on the wax layer. Results: For I. sanguinea and V. coignetiae, the sources of PM did not affect the growth response. P. multifida showed high chlorophyll a, b, total chlorophyll, and carotenoid content in carbon black as well as high Fv/Fm and total leaf area, thereby proving that carbon black helped plant growth. By PM sources, sPM10 showed a significant difference in three plant species, sPM2.5 in two plant species, and wPM10 in one plant species, indicating that sPM10 was most affected by PM sources. Conclusion: Carbon black increased the leaf area by affecting the growth of P. multifida. This plant can be effectively used for PM reduction by increasing the adsorption area. I. sanguinea and V. coignetiae can be used as economical landscaping plants since they can grow regardless of PM sources.

• 한국미생물·생명공학회지
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• 제17권5호
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• pp.461-467
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• 1989

Hansenula polymoypha의 배양조건과 배지의 탄소원에 따른 alcohol-oxidase의 생성능을 비교하기 위하여 H. polymorpha CBS 4732, H. polymorpha CBM 11, 그리고 H. polymorpha Cooney의 3균주에 대하여 실험하였다. 배양조건에 따른 효소생성은 glucose를 탄소원으로 첨가한 mineral salt medium에서 균체를 정상기까지 배양하여 methanol이 함유된 배지에서 재배양하는 2단계 배양법의 경우가 균체를 직접 methanol 배지에 배양한 경우보다 효율적이었으며 생성된 총효소량은 전자의 경우가 후자에 비해 1.9배정도 많았다. 다음 탄소원에 따른 효소생성능을 비교하였다. 먼저 직쇄 alcohol을 탄소원으로 사용한 경우 mothanol을 제외한 ethanol, propanol, butanoL, 그리고 pentanol에서는 효소가 생성되지 않았고 또한 이 직쇄 alcohol을 methanol과 혼합한 경우에도 극미량의 생성에 그쳤다. 여러 가지 탄소화합물 (glucose, xylose, lactose, glycerol, galactose, saccharose, sorbose, tactic acid acetic acid)을 탄소원으로 사용하면 methanol에 의해 생성된 효소량의 1/10 정도 생성되었고 이들을 methanol과 혼합사용하면 효소생성량은 급격히 증가하였고, 특히 lactose와 tactic acid의 경 우는 methanol 단독사용시 보다 오히려 다량 생성되었다. 시험 3균주 중에서는 어떤 경우에서든지 H. polymorpha CBS 4732가 alcohol-oxldase 생성능이 가장 좋은 것으로 나타났다.