我国优势油脂类生物柴油植物蓖麻的种质资源发掘和生物柴油利用

发展可再生生物质能源是解决人类能源危机和环境污染的重要途径。利用边际土地发展油脂类生物质能是生物质能的重要组成部分。蓖麻因为适应性强和油脂成份独特被誉为"理想的生物柴油植物"。蓖麻是我国优势油脂类能源植物,利用边际土地,发展蓖麻产业为我国生物柴油产业化提供原料,是我国现阶段生物柴油产业化发展的相对理想而又现实的选择,而且具有重要的发展前景和巨大的发掘潜力。立足我国现阶段生物柴油产业化的瓶颈问题,着重阐述了蓖麻种质资源发掘的现状、优良品种培育的途径和发展前景,以及利用蓖麻种子油生产商业化生物柴油的现状,以期推动我国利用边际土地发展蓖麻产业以及生物柴油商业化生产。     

生物柴油研究进展

介绍了国内外生物柴油的发展现状,探讨了我国发展生物柴油的原料来源途径,包括木本油料植物、转基因油料作物、废弃油脂、微生物油脂和微藻油脂等,综述了制备生物柴油的化学法、酶法、超临界法等生产技术及其进展,概括了当前生物柴油主要的品质问题与改性对策,分析了生物柴油副产物的高值化利用策略,指出了我国生物柴油产业化面临的原料、技术和生物炼制方面的主要问题。     

生物柴油利用概况及其在中国的发展思路

 石化燃料是当前人类使用的主要能源,但其日益消耗殆尽,同时造成了严重的温室效应和环境污染问题,因此,生物柴油被当作石化燃料的绿色替代品,许多国家都在大力研发 。该文阐述了生物柴油的本质及其较石化柴油咱使用上的优良特性,综述了生物柴油主要在欧美国家中的发展现状及其它国家的研发动态,特别是以大豆（Glycine max）和油菜（Brassica campestris）等油料作物为主的生物柴油原料生产状况。在分析了我国油料生产与食用消费现状、受国际生物柴油大力发展的影响的程度及油料作物与粮食生产对耕地资源的激竞争矛盾的基础上,提出了充分利用盐碱地、贫瘠、荒漠与退耕还林地,通过种植抗逆性强的油料植物发展我国生物柴油的思路。     

一株耐NaHCO3高含油绿藻的筛选鉴定

正传统化石能源储量日益减少,化石能源燃烧后产生的二氧化碳是全球变暖的主要元凶,因此,能够替代传统化石燃料、可再生的新型能源受到广泛的关注,生物柴油便是较为理想的新型能源之一[1]。虽然油料作物、废弃油脂等为生物柴油生产提供了部分原料,但其成本、规模及可持续性受多种因素的制约[2]。目前,利用光合自养的微藻生产生物柴油的潜在价值已经得到广泛的认可,微藻生物柴油技术在减少CO_2排放、大规模培养、产油效率等方面的优势日益突显[3]。微藻生物柴油的生     

微生物在生物能源生产中的应用(英文)

生物可再生能源是最有前景的石油替代品之一.生物能源的生产原料包括:植物、有机废弃物和微生物.微生物在生物能源生产上有着广泛的应用,利用微生物制备的主要生物能源包括:生物柴油、生物乙醇、生物甲烷等.某些微生物如微藻和真菌可以生产大量油脂,这些油脂可以转化为生物柴油;有些微生物如酵母可以将糖类、淀粉以及纤维素转化为燃料乙醇,添加乙醇的汽油或柴油燃烧排放明显降低;还有些厌氧微生物可以将有机废弃物转化为甲烷,可用做家用燃气、车用燃气或发电.除此之外微生物还具有在生产能源的同时治理环境污染的优势.总之研究开发微生物在生物能源生产中的应用有利于世界可持续发展.     

生物柴油的现状与进展

生物柴油是清洁的可再生能源，它以大豆和油菜籽等油料作物、油棕和黄连木等油料林木果实、工程微藻等油料水生植物以及动物油脂、废餐饮油等为原料制成的液体燃料，是优质的石油柴油代用品。生物柴油是典型“绿色能源”，大力发展生物柴油对经济可持续发展，推进能源替代，减轻环境压力，控制城市大气污染具有重要的战略意义。     

发展生物柴油产业的挑战与对策的探讨

生物柴油是一种由可再生资源生产的优质清洁燃料,发展生物柴油不仅可以保护环境,减少温室气体排放,而且可以缓解我国石油进口的压力,推动新农村建设。但由于植物油脂价格的飙升,生物柴油产业发展面临仅生产生物柴油燃料在经济上难以立足的挑战。本文从发展生物柴油原料资源,生产技术以及生物柴油化工技术开发的现状与未来发展动态进行分析,探讨了促进我国生物柴油产业健康发展的对策。[编者按]     

微生物途径发展生物柴油产业

生物柴油实际上就是生物油脂与甲醇或乙醇在酸、碱催化剂的作用下进行脂交换反应而制造的脂肪酸甲酯或乙酯;也可以在常温下由微生物脂酶催化进行酯化反应,其产品是一种可再生燃料,能替代石油柴油。这些生物柴油主要来自植物油或其它生物油脂,也有用废弃食用油为原料通过甲醇的酯交换反应来制造生物柴油的。研发这些生物柴油也可以说是节能的一项重要措施。在我国,对石油的需求量越来越大,石油进口量也随之猛增,显示出我国的能源形势日益严峻。面对这种情况,发展可再生能源或替代能源是个必然趋势,生物柴油便是其中之一。目前我国生物柴油的…     

适于沙漠地下水培养的耐碳酸氢钠产油微藻

<正>能源危机是全世界面临的共同问题,采用可再生能源替代化石能源是出路之一。生物柴油作为一种清洁可再生能源备受瞩目[1—3]。目前,生物柴油主要以大豆和油菜、油棕和麻风树等油料植物以及动物油脂、废餐饮油等作为原料。但是动物油脂、废餐饮油原料有限,而油料植物生产油脂存在占地面积大、生产周期长等缺点,不宜作为未来生物柴油的主要来源。相比之下,产油微藻具有生长周期短、单位面积产量高等优点[4],被认为是生物柴油     

微藻减排CO2制备生物柴油的研究进展

碳减排与可再生能源的开发利用是研究可持续发展的热点,而微藻在此方面具有巨大优势.利用微藻减排CO2合成生物柴油生产原料油脂,对于解决能源短缺和全球变暖具有重大战略意义.将碳减排与微藻生物柴油的制备方法相结合,对微藻转化CO2合成生物油脂的机制,微藻油脂积累的影响因素以及国内外在工业上的研究概况等方面进行综合归纳和评述,并对微藻生物油脂的发展前景进行了展望.     

Second Generation Biofuels: High-Efficiency Microalgae for Biodiesel Production

The use of fossil fuels is now widely accepted as unsustainable due to depleting resources and the accumulation of greenhouse gases in the environment that have already exceeded the “dangerously high” threshold of 450 ppm CO₂-e. To achieve environmental and economic sustainability, fuel production processes are required that are not only renewable, but also capable of sequestering atmospheric CO₂. Currently, nearly all renewable energy sources (e.g. hydroelectric, solar, wind, tidal, geothermal) target the electricity market, while fuels make up a much larger share of the global energy demand (～66%). Biofuels are therefore rapidly being developed. Second generation microalgal systems have the advantage that they can produce a wide range of feedstocks for the production of biodiesel, bioethanol, biomethane and biohydrogen. Biodiesel is currently produced from oil synthesized by conventional fuel crops that harvest the sun’s energy and store it as chemical energy. This presents a route for renewable and carbon-neutral fuel production. However, current supplies from oil crops and animal fats account for only approximately 0.3% of the current demand for transport fuels. Increasing biofuel production on arable land could have severe consequences for global food supply. In contrast, producing biodiesel from algae is widely regarded as one of the most efficient ways of generating biofuels and also appears to represent the only current renewable source of oil that could meet the global demand for transport fuels. The main advantages of second generation microalgal systems are that they: (1) Have a higher photon conversion efficiency (as evidenced by increased biomass yields per hectare): (2) Can be harvested batch-wise nearly all-year-round, providing a reliable and continuous supply of oil: (3) Can utilize salt and waste water streams, thereby greatly reducing freshwater use: (4) Can couple CO₂-neutral fuel production with CO₂ sequestration: (5) Produce non-toxic and highly biodegradable biofuels. Current limitations exist mainly in the harvesting process and in the supply of CO₂ for high efficiency production. This review provides a brief overview of second generation biodiesel production systems using microalgae.     

Plant triacylglycerols as feedstocks for the production of biofuels

Triacylglycerols produced by plants are one of the most energy-rich and abundant forms of reduced carbon available from nature. Given their chemical similarities, plant oils represent a logical substitute for conventional diesel, a non-renewable energy source. However, as plant oils are too viscous for use in modern diesel engines, they are converted to fatty acid esters. The resulting fuel is commonly referred to as biodiesel, and offers many advantages over conventional diesel. Chief among these is that biodiesel is derived from renewable sources. In addition, the production and subsequent consumption of biodiesel results in less greenhouse gas emission compared to conventional diesel. However, the widespread adoption of biodiesel faces a number of challenges. The biggest of these is a limited supply of biodiesel feedstocks. Thus, plant oil production needs to be greatly increased for biodiesel to replace a major proportion of the current and future fuel needs of the world. An increased understanding of how plants synthesize fatty acids and triacylglycerols will ultimately allow the development of novel energy crops. For example, knowledge of the regulation of oil synthesis has suggested ways to produce triacylglycerols in abundant non-seed tissues. Additionally, biodiesel has poor cold-temperature performance and low oxidative stability. Improving the fuel characteristics of biodiesel can be achieved by altering the fatty acid composition. In this regard, the generation of transgenic soybean lines with high oleic acid content represents one way in which plant biotechnology has already contributed to the improvement of biodiesel.     

生物柴油原料资源高油脂微藻的开发利用

生物柴油作为化石能源的替代燃料已在国际上得到广泛应用。至今生物柴油的原料主要来自油料植物, 但与农作物争地的情况以及较高的原料成本限制了生物柴油的进一步推广。微藻作为高光合生物有其特殊的原料成本优势, 微藻的脂类含量最高可达细胞干重的80%。利用生物技术改良微藻, 获得的高油脂基因工程微藻经规模养殖, 可大大降低生物柴油原料成本。介绍了国内外生物柴油的应用现状, 阐述了微藻作为生物柴油原料的优势, 对基因工程技术调控微藻脂类代谢途径的研究进展, 以及在构建工程微藻中面临的问题和应采取的对策进行了综述和展望。     

Opportunities for renewable bioenergy using microorganisms

Global warming can be slowed, and perhaps reversed, only when society replaces fossil fuels with renewable, carbon-neutral alternatives. The best option is bioenergy: the sun's energy is captured in biomass and converted to energy forms useful to modern society. To make a dent in global warming, bioenergy must be generated at a very high rate, since the world today uses approximately 10 TW of fossil-fuel energy. And, it must do so without inflicting serious damage on the environment or disrupting our food supply. While most bioenergy options fail on both counts, several microorganism-based options have the potential to produce large amounts of renewable energy without disruptions. In one approach, microbial communities convert the energy value of various biomass residuals to socially useful energy. Biomass residuals come from agricultural, animal, and a variety of industrial operations, as well as from human wastes. Microorganisms can convert almost all of the energy in these wastes to methane, hydrogen, and electricity. In a second approach, photosynthetic microorganisms convert sunlight into biodiesel. Certain algae (eukaryotes) or cyanobacteria (prokaryotes) have high lipid contents. Under proper conditions, these photosynthetic microorganisms can produce lipids for biodiesel with yields per unit area 100 times or more than possible with any plant system. In addition, the non-lipid biomass can be converted to methane, hydrogen, or electricity. Photosynthetic microorganisms do not require arable land, an advantage because our arable land must be used to produce food. Algae or cyanobacteria may be the best option to produce bioenergy at rates high enough to replace a substantial fraction of our society's use of fossil fuels.     

加快微生物油脂研究为生物柴油产业提供廉价原料

当前国内外致力于发展生物柴油,因其性能优良,成为化石柴油的替代品。由于以植物油脂生产生物柴油原料成本占总成本的70％-85％,所以亟待开发廉价油脂资源。微生物油脂主要是微生物利用碳水化合物合成的甘油脂,其脂肪酸组成和植物油相近。产油微生物具有资源丰富、油脂含量高、碳源利用谱广等特点,开发潜力大。然而,目前微生物油脂生产成本偏高,研究工作仍以富含多不饱和脂肪酸的高附加值菌油为目标。随着现代分子生物学和生物化工技术的发展,对产油微生物菌种筛选、改良、代谢调控和发酵工程的研究日趋深入,将降低微生物油脂生产成本,为未来生物柴油产业提供廉价原料。     

广谱碳源产油酵母菌的筛选

对10株酵母菌利用不同单糖为碳源条件下菌体内积累油脂的能力进行了初步考察,并对菌油进行了分离和脂肪酸组成分析。实验发现,以葡萄糖为唯一碳源时有9株菌油脂含量超过自身细胞干重的20%,可以界定为产油微生物。其中6#菌(T.cutaneumAS2.571)利用葡萄糖发酵菌体油脂含量达到65%(W/W)。所有实验菌株都能同化多种单糖,其中1#菌(L.starkeyiAS2.1390)、4#菌(R.toruloidesAS2.1389)和11#菌(L.starkeyiAS2.1608)表现出对碳源利用的广谱性,能转化五碳糖木糖和阿拉伯糖并在菌体内积累油脂,油脂含量最高达到26%。脂肪酸组成分析结果表明,菌油富含饱和及低度不饱和长链脂肪酸,其中棕榈酸、油酸和亚油酸三者之和占总脂肪酸组成的90%以上,脂肪酸组成分布类似于常见的植物油。这些结果对利用产油微生物转化木质纤维素水解混合糖获取油脂资源的研究具有重要意义。     

The effect of physicochemical conditions and nutrient sources on maximizing the growth and lipid productivity of green microalgae

Biodiesel is a renewable fuel produced mostly from edible and non‐edible vegetables, by transesterification of neutral lipids (triacylglycerols). However, vegetable oil‐based biodiesel production competes with food crops for arable land, increasing food prices and leading to biodiversity loss. The production of biodiesel from oleaginous microorganisms – particularly microalgae – has attracted attention due to the higher lipid productivity of these organisms, when compared with vegetables. Several environmental factors – including light, temperature, pH and the presence of nutrients (particularly nitrogen, phosphorus and iron) – influence directly the ability of microalgae to produce and store triacylglycerols and other lipids, and also modulate microalgal growth. Although some environmental factors affect several species in a similar manner, differential responses between species are frequent, highlighting the importance of identifying optimal cultivation conditions for each species, to balance growth and lipid productivity for biodiesel production. Here, we reviewed the particular influence of the physicochemical and nutritional factors on the growth and lipid productivity of different green oleaginous microalgae species.     

Microalgae Versus Land Crops as Feedstock for Biodiesel: Productivity,Quality, and Standard Compliance

Despite certain environmental advantages over fossil diesel, land crop-derived biodiesels may not satisfy the increasing worldwide demand for transportation fuels. As an abundant photosynthesizer, algae could be an adequate surrogate for biodiesel production. Nevertheless, high production costs, scarce selected species, and inaccurate assumptions about production yields represent industrial uncertainties. In this study, a reliable approach to analyzing algal biodiesel production has been developed based on species-to-species variations in oil productivity and quality. This approach compares biodiesels from Chlorophyta strains with land crop feedstock according to (i) potential yields, (ii) oil quality, and (iii) compliance with biodiesel quality standards. Algal yields were assessed by (i) extrapolating the strain-specific laboratory results to commercial-scale growth systems; (ii) converting volumetric to areal biomass productivity; and (iii) estimating oil yields for each strain, as the product of their projected areal biomass productivity for each growth system, and the oil percentage in biomass as determined in the laboratory. Biodiesel fuel properties were estimated by using fatty acid methyl ester profile predictive models. The Chlorophyta strains in this study provided annual oil yields that were generally higher than those of land crops by one order of magnitude. Six strains yielding more than 40 mg oil l^?1 day^?1 were identified as adequate for sustaining biodiesel production. Trebouxiophyceae algae were the most productive. Critical biodiesel parameters from both feedstock types suggest that most microalgae-derived biodiesels meet international fuel quality standards with better values than those of land crops. Because some of the highly productive feedstock does not simultaneously meet all the standards for a high quality biodiesel, optimization solutions are discussed.     

Biodiesel production from various feedstocks and their effects on the fuel properties

Biodiesel, which is a new, renewable and biological origin alternative diesel fuel, has been receiving more attention all over the world due to the energy needs and environmental consciousness. Biodiesel is usually produced from food-grade vegetable oils using transesterification process. Using food-grade vegetable oils is not economically feasible since they are more expensive than diesel fuel. Therefore, it is said that the main obstacle for commercialization of biodiesel is its high cost. Waste cooking oils, restaurant greases, soapstocks and animal fats are potential feedstocks for biodiesel production to lower the cost of biodiesel. However, to produce fuel-grade biodiesel, the characteristics of feedstock are very important during the initial research and production stage since the fuel properties mainly depend on the feedstock properties. This review paper presents both biodiesel productions from various feedstocks and their effects on the fuel properties. JIMB 2008: BioEnergy - Special issue.