Production of lipids for bioconversion to biodiesel using crude glycerol as a raw material and employing new isolated microorganisms

粗甘油是生物柴油生产活动的副产品。生产的甘油大约相当于生物柴油产量的10%。目前，粗甘油被认为是一种废物，生物柴油生产商正在寻找不同的方法来处理/回收甘油。因此，迫切需要发明并实现粗甘油的可持续利用。如果甘油能够被回收利用来产生脂类，供生产商在同一地点(生产甘油)使用，这将有助于生物柴油生产商提振经济。因此，本研究的主要目的是利用我们实验室分离到的高积累脂肪的高活性微生物菌株，开发一种以粗甘油为原料生产油脂(单细胞油)的经济工艺。我们与我们的工业合作伙伴就该项目进行的初步成本估计显示，油脂生产的成本约为每吨300-400美元，符合工业合作伙伴生产计划的要求。该项目的具体目标包括：甘油的分析；不同浓度的甘油(4-15%w/v)；灭菌和未灭菌甘油的产脂测试；粗甘油中的杂质对微生物生长和脂肪积累的影响；15L、150L和2000L规模的优化条件下产脂的演示；发酵上清液中次级代谢物的鉴定；用均质器(加压)从生物质中提取油脂/脂类，转化为生物柴油和脱脂生物量的营养价值；以及最终成本估算。此外，这项研究非常及时，将有助于加拿大工业开发环保和商业可行的生物柴油，以加强加拿大的环境政策。1名硕士和1名研究助理将在这个项目中接受培训。

Crude glycerol is generated as a by-product of biodiesel production activity. Approximately, the glycerol produced is equal to 10% of the biodiesel produced. At present, crude glycerol is considered as a waste and biodiesel producers are looking different ways to dispose/recycle their glycerol. Thus, there is an urgent need to invent and implement a sustainable use of crude glycerol. If the glycerol can be recycled to generate lipids which could be used by the producer at the same site (at which glycerol is produced), it would help biodiesel producers boost their economy. Therefore, the principal objective of the present research is to develop an economical process for lipids (single cell oil) production using crude glycerol (of Biocardel) as a raw material using high lipid accumulating hyperactive microbial strains, isolated in our laboratory. Our preliminary cost estimate conducted in collaboration with our industrial partner on this project revealed that the cost of lipid production was approximately 300-400$ per tone, which meets the requirement of the industrial partner in their production plan. The specific objectives of the project include: analysis of glycerol; different concentrations of glycerol (4-15%w/v); sterilized versus non-sterilized glycerol shall be tested for lipid production; impact of impurities in crude glycerol on microbial growth and lipid accumulation; demonstration of lipid production at 15L, 150L and 2000L scale at optimized conditions; identification of secondary metabolites in the fermentation supernatant; extraction of oil/lipids from biomass with homogenizer (under pressure) and conversion to biodiesel and nutritive value of de-fatted biomass; and final cost estimation. Furthermore, this research is very timely and will aid Canadian industry to develop eco-friendly and commercially viable biodiesel strengthening Canada's environmental policy. 1 MSc and 1 research associate will be trained in this project.