Author:

Abstract:

In the search for biofuels which are not competing with food, oleaginous micro-organisms gain increased interest. Specific strains of yeast, algae, fungi and bacteria can produce intracellular oil (single cell oils) under specific growth conditions. Besides the selection of the micro-organisms, the optimization of the growth conditions and downstream processing, new analytical methods have to be developed to monitor the whole process and to evaluate the final products. In order to analyze the single cell oils, different objectives can be set: (1) total lipid content, (2) fatty acid profile and (3) lipid classes. Each of these objectives need a different approach and will give information about the capacity to optimize the process and about the valorization potential of the final products. This research is focused on the development of methods that are robust, sensitive, labour and cost effective and that give a maximum of information. Most lipid analysis methods and techniques nowadays include two steps: (1) extraction of the lipids, followed by (2) a transesterification reaction. The new method that will be presented combines both steps into one single step and allows determination of the total lipid content and fatty acid profile in an easy way. The method will be compared with a classical method and an enhanced classical method using microwave assisted extraction, followed by a transesterification reaction. Information with respect to the fatty acid profile in function of the growth conditions can be obtained. This will give the opportunity to optimize the valorization possibilities and the flexibility of producing lipids with the most interesting fatty acid profile.