• 한국미생물생명공학회:학술대회논문집
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• 한국미생물생명공학회 1986년도 추계학술대회
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• pp.509.2-509
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• 1986

Owing to the growing interest in the production of fuels and chemicals from biomass the well-know butanol-acetone fermentation as carried out by Clostridium acetobutylicum has been intensely studied again in recent years. Several solvent-yielding fermentation processes were established which are operated by using batch cultures or continuous cultures. 1 could be shown that under conditions of phosphate limitation an asporogenous mutant of C. acetobutylicum establishes itself in a chemostat which produces the solvents continuously. Attempts have been made to change the butanol/acetone ratio in favor of butanol production. A corresponding shift of the product spectrum can be achieved by carbon monoxide addition to the head space of the fermentation (B.H. Kim et al., App. Envioron. Microbiol. 48, 764-770 1984) or by iron limitation. Progress has been made in understanding the mechanism underlying the shift from acid to solvent prodcction. Experimental results are in agreement with the view that intracellular accumulation of acetic and butyric acid results in a shortage of phosphate and coenzyme A. This shortage may serve then as signal for the synthesis of the enzymes involved in the formation of acetone and butanol.

• 한국콘텐츠학회논문지
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• 제16권2호
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• pp.618-632
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• 2016

드라마 제작산업의 가격결정 방식은 다중가격 체계를 형성하고 있다. 생산요소 가격은 방송사업자별, 제작주체별, 드라마 장르별로 차별화가 이루어지고 있다. 다중가격 체계에서 가격결정에 영향을 미치는 요인들은 생산요소의 희소성과 대체재의 유무, 제작비 규모, 명성 효과, 경쟁의 정도, 생산요소를 선택하는 주체 등이다. 스타 연기자에게 가격은 자신의 역량을 평가받는 기준으로 작용하는 동시에 자존심이라는 명성과 직결되는 기준으로 인식되고 있다. 이로 인해, 연기자 가격은 기존의 최고 가격을 경쟁자가 뛰어넘으며 경쟁하는 시소효과를 나타내고 있는 반면, 작가 가격은 최고 대우를 받고 있는 특정 작가의 가격 이하에서 제한적으로 상승하는 사다리 효과를 나타내고 있다. 현재는 제작비 규모의 상승 속도가 생산요소 가격의 상승 속도를 따라가지 못하는 상황이기 때문에 런닝개런티 제도를 적용하여 합리적인 시장 가격 형성을 위한 기준이 마련되어야 할 시점이다.

• 대한한방종양학회지
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• 제5권1호
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• pp.137-150
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• 1999

Macrophage play a major role in host defence against infection and tumor development and this activity is regulated through the production of several mediators. In particular, the production of NO by macrophages mediates killing or growth inhibition of tumor cells, bacteria, fungi and parasites. However, over-expression of iNOS by various stimuli, resulting in over-production of NO, contributes to the pathogenesis of septic shock and some inflammator and auto-immune disease. Therefore, it would be valuable to develop potent and selective inhibitors of for potential therapeutic use. Thus the agent that supprees the expression of iNOS mRNA or enzyme protein will be usefull for the prevention of various diseases. We are intersted in identifying selective inhibitiors of iNOS which might be useful intreating inflammatory human diseases. In summary, we have demenstrated that scopoletin, isolated from Seman Armenicae and Radix Trichosanthis the production of NO induced by $IFN-\gammer$ plus LPS in RAW 264.7 macrophages, The mechanism for the inhibition of NO production was due to suppression of the expression of iNOS mRNA or enzyme protein.

• Journal of Microbiology and Biotechnology
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• 제20권2호
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• pp.346-349
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• 2010

Coenzyme $Q_{10}$ ($CoQ_{10}$) production from Rhizobium radiobacter T6102 was monitored under various oxygen supply conditions by controlling the agitation speeds, aeration rates, and dissolved oxygen levels. As the results, the $CoQ_{10}$ production was enhanced by limited oxygen supply. To investigate whether the $CoQ_{10}$ production is associated with its physiological functions of electron carrier and antioxidant, the effects of sodium azide and hydrogen peroxide on the $CoQ_{10}$ production were studied, showing that the $CoQ_{10}$ contents were slightly enhanced with increasing sodium azide (up to 0.4 mM) and hydrogen peroxide (up to $10\;{\mu}M$) concentrations. These results suggest the plausible mechanism where the limited electron transfer stimulating the environments of limited oxygen supply and oxidative stress could accumulate the $CoQ_{10}$, providing the relationship between the $CoQ_{10}$ physiological functions and its regulation system.

• Preventive Nutrition and Food Science
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• 제7권4호
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• pp.353-357
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• 2002

We have previously demonstrated that kudzu root extracts have a hypocholesterolemic effect on rats fed diets high in fat and cholesterol. To further elucidate the mechanism involved, in this study we investigated the effect of water extracts of kudzu root, Pueraria radix, on the production of apolipoprotein B$_{100}$ (APo B$_{100}$) in HepG$_2$ liver cells and secretion of apolipoprotein B$_{48}$ (Apo B$_{48}$) in Caco$_2$ cells. Human cell lines, HepG$_2$ liver cells and Caco$_2$ intestinal epithelial cells, were grown with various concentrations (0%, 0.5%, 1.0%, 1.5%, 2.0%) of water extracts of kudzu root in the media. The kudzu root extract decreased Apo B$_{100}$ production and secretion. Treatment of HeP G$_2$ cells with the kudzu root extract also significantly decreased the intracellular total and free cholesterol concentration, and also decreased esterified cholesterol but was only significant at the highest dose of 2%. Apo B$_{48}$ production, but not secretion, from enterocytes was lowered by the kudzu root extracts. This research provided evidence that the hypocholesterolemic properties of kudzu root may be a consequence of decreased production and secretion of Apo B$_{100}$ in the liver and Apo B$_{48}$ in the intestine.

• Asian-Australasian Journal of Animal Sciences
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• 제6권2호
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• pp.275-279
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• 1993

A study using dairy heifers was conducted to determine the effect of environmental temperature on heat production differing in feed intake level. The design consisted of three levels of feed intake (low, medium and high) and two environmental chamber temperature (15 and $30^{\circ}C$) with four replications in each treatment. Rectal temperature (RT), respiration rate (RR), heart rate (HR) and heat production (HP) were then measured. At the both environmental temperature, RT, RR and HR increased with the increase in feed intake level. The RT and RR also increased with the elevation of environmental temperature. The HP of $30^{\circ}C$ was significantly higher (4.8-8.9%) than $15^{\circ}C$. The estimated metabolizable energy requirement for maintenance (MEm) was higher (p<0.05) at $30^{\circ}C$ ($554.7kJ/kg^{0.75}$ d) than $15^{\circ}C$ (464.9 kJ/kgd). It was suggested that the decreasing in productive efficiency under hot environmental conditions partly associated with the increase in HP, which associated with the change in heat loss mechanism from sensible path to evaporative path.

• 한국식품영양과학회지
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• 제26권5호
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• pp.972-977
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• 1997

Conjugated dienoic derivatives of linoleic acid(CLA) are a series of positional and gemotric isomers of linoleic acid which are found naturally in food, mainly dietary products and breef. We studied the effects of CLA on the growth of tumor cells and the production of interleukin-1(IL-1) and interleukin-2(IL-2). CLA treatment markedly inhibited the growth of Yac-1 cells and sarcoma-180 cells by 99 and 82% to that of control, respectively, after four days of incubation at 37$^{\circ}C$. To elucidate the immunological mechanism of antitumor activity of CLA, spleen cells of Balb/c mouse were exposed to 31, 63, 125, 250 $\mu\textrm{g}$ of CLA per ml for 24 hrs at 37$^{\circ}C$. The culture supernatants of CLA-exposed spleen cells reduced the production of IL-1 and IL-2 in all of the test conditions. These results indicate that the anticarcino-genic effect of CLA was mediated by the other actions rather than the production of the Il-1 or IL-2. We suggest that CLA might have an antiinflammatory effect in part due to its inhibitory action on the production of IL-1.

• Biotechnology and Bioprocess Engineering:BBE
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• 제11권2호
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• pp.100-104
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• 2006

In this study, we investigated the relationship between the morphology and the rheological properties of Penicillium citrinum to improve the production of neo-fructosyltransferase (neo-FTase). In a 2.5 L bioreactor culture of P. citrinum, it was observed that agitation speed and aeration rate had significant effects on the production of neo-FTase and that maximum cell mass and neo-FTase production obtained at 500 rpm and 1.5vvm were 8.14 g/L and $53.2{\times}10^{-3} U/mL$, respectively. Cell mass and neo-FTase production increased to 91.53 and 25.17%, respectively. In the morphology and rheology studies, P. citrinum showed a typical pellet morphology that was explained by a shaving mechanism; this phenomenon was significantly affected by carbon sources. The rheology of neo-FTase fermentation by P. citrinum was dependent on cell growth and fungal morphology.

• Journal of Microbiology and Biotechnology
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• 제17권9호
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• pp.1563-1567
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• 2007

AfsKav is a eukaryotic-type serine/threonine protein kinase, required for sporulation and avermectin production in Streptomyces avermitilis. In terms of their ability to complement SJW4001 (${\Delta}afsK$-av), afsK-av mutants T165A and T168A were not functional, whereas mutants T165D and T168D retained their ability, indicating that Thr-165 and Thr-168 are the phosphorylation sites required for the role of AfsKav. Expression of the S-adenosylmethione synthetase gene promoted avermectin production in the wild-type S. avermitilis, yet not in the mutant harboring T168D or T165D, demonstrating that tandem phosphorylation on Thr-165 and Thr-168 in AfsKav is the mechanism modulating avermectin production in response to S-adenosylmethione accumulation in S. avermitilis.

• 대한기계학회논문집
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• 제17권1호
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• pp.190-199
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• 1993

본 연구에서는 화염간 상호작용이 연소생성물 형성에 미치는 영향을 규명하기 위한 작업의 일환으로 대표적 연소 생성 공해 물질의 하나인 NO를 택하여 상호작용하 의 층류 확산화염에서 NO의 생성이 어떻게 이루어지는가를 검토 하고자 한다. 이를 위하여 기본적 다화염계인 2-화염계를 모사하는 수학적 모델을 수립하고 수치 계산을 통한 이론적 방법을 위주로하여 2개의 층류 확산 화염이 나타내는 상호작용 특성과 화 염간 상호작용이 NO형성에 미치는 영향을 규명하고자 한다.