• 한국미생물·생명공학회지
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• 제18권1호
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• pp.6-11
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• 1990

Clostridium 속 세균에서 biomass의 생물학적 전환에 의한 수소 생성에 관하여 조사하기 위해 4균종을 대상으로 biomass를 구성하는 당류 이용도 및 그로부터의 수소 생성을 검토하였다. 효율적인 수소 생성 세균은 Cl.butyricum과 Cl.pasteurianum으로 xylose, cellobiose를 포함한 그외 단당, 이당류에서 높은 수소 생성능을 나타내었으며, 특히 Cl.butyricum의 경우, starch, xylan외에도 pectin의 이용성이 비교적 우수한 것으로 관찰되었다. 포도당(1) 이용시 회분 발효를 통하여 Cl.butyricum이 생성하는 유기산 (acetate와 butyrate)의 molar ratio(A/B)는 0.7-0.8을 나타내었다. Cl.butyricum의 회분 발효시 수소 생성에 영향을 미치는 배양조건을 검토하기 위해 pH, phosphate의 농도, glucose의 농도 및 배양 초기 대사산물(acetate, butyrate)의 영향을 관찰하였다.

• Journal of Plant Biotechnology
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• 제34권2호
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• pp.103-109
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• 2007

The increasing industrialization of the world has led to precipitous rise for the demand of petroleum-based fuels. The world is presently confronted with the twin crises of fossil fuel depletion and environmental pollution. The search for alternative fuels, which promise a harmonious correlation with sustainable development, energy conservation, efficiency and environmental preservation, has become highly pronounced in the present. Bioenergy is playing an increasingly important role as an alternative and renewable source of energy. Use of Bioenergy has several potential environmental advantages. The most important perhaps is reduction in life cycle greenhouse gases emissions relatives petroleum fuels, since bioenergy is derived from plants which convert Carbon dioxide ($CO_{2}$) into Carbohydrates in their growth. Bioenergy includes solid biomass, biomas and liquid bio-fuels which are fuels derived from crop plants, and include biomass that's directly burned. The two most important bio liquid fuels today are bioethanol from fermenting grain, grass, straw or wood, and biodiesel from plant seed oil.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2009년도 추계학술대회 논문집
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• pp.520-520
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• 2009

Organic by-products derived from cellulose and lignin during organosolv pretreatments of yellow poplar wood (Liriodendron tulipifera) in the presence of $H_2SO_4$ and NaOH as catalysts, respectively, were subjected to various analyses to elucidate their effects on further performance of biological ethanol fermentation and provide preliminary data for the structure and utilization of organosolv lignin. Monomeric sugars amounted to ca. 2.2-7.7% in the organosoluble fraction of the organosolv pretreatment with $H_2SO_4$, while significantly low amount of sugars (0.2-0.3%) were determined in that of the organosolv pretreatment with NaOH. In case of addition of $H_2SO_4$ during organosolv pretreatment of biomass, a fermentation of the organosoluble fraction could be considered as an essential process to increase an efficiency of biomass utilization as well as yield of bioethanol. Precipitates, insoluble by-products in the solvent mixture, were also cficiency oed by diverse analytical methods and revealed that these were typically composed of a lignin moiety regardless of catalyst. According to the results of nuclear magnetic resonance (NMR), Fourier Tcinsform Infrared Spectroscopy (FT-IR) and Gel permeation chromatograp r (GPC), the main components of precipitates seem to be lignin polymers. However, their structures could be slightly modified during pretreatment and mixed with some carbohydrates by chemical bonds and/or physical associations.

• Ocean and Polar Research
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• 제34권4호
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• pp.365-384
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• 2012

Microalgae are photosynthetic microorganisms that are highly productive in the presence of basic renewable natural sources (light, $CO_2$, water and nutrients). They can synthesize lipids, carbohydrates and proteins in a small number of days. Subsequently, these carbon-captured products can be processed into both biofuels and valuable co-products. Additionally, microalgae would be an ideal feedstock for replacing land-based food crops with cellular products as high energy density transportation fuels. These microscopic organisms could contribute a significant amount of renewable energy on a global scale. In Korea, microalgae biofuel research was common in the early 1990s. The research activities were unfortunately stopped due to limited governmental funds and low petroleum prices. Interest in algal biofuels in Korea has been growing recently due to an increased concern over oil prices, energy security, greenhouse gas emissions, and the potential for other biofuel feedstock to compete for limited agricultural resources. The high productivity of microalgae suggests that much of the Korean transportation fuel requirements can be met by biofuels at a production cost competitive with the increasing cost of petroleum seen in early 2008. At this time, the development of microlalgal biomass production technology remains in its infancy. This study reviewed microalgae culture systems and biomass production, harvesting, oil extraction, conversion, and technoeconomical bottlenecks. Many technical and economic barriers to using microalgal biofuels need to be overcome before mass production of microalgal-derived fuel substitutes is possible. However, serious efforts to overcome these barriers could become a large-scale commercial reality. Overall, this study provides a brief overview of the past few decades of global microalgal research.