Arachidonic acid (ARA) and eicosapentaenoic acid (EPA) are important for human health and are produced by the fungus Mortierella alpina. Fermentation conditions may affect fatty acid profile of produced oil. Substrates in solid-state fermentation are usually renewable and low-cost agro-industrial waste. The aim of this research is to study simultaneous production of ARA and EPA by M. alpina CBS 528.72 in solid-state fermentation. Date waste and soybean meal served as carbon and nitrogen sources, respectively. Plackett-Burman design was used to evaluate the impact of eleven process variables on ARA and EPA production. Analysis of the results showed that the main variables with significant impact on production include seed age, and supplementation of linseed oil and nitrogen. These three variables were then studied in a central composite design for the optimization of production of both fatty acids. Finally, reconfirmation test was conducted to obtain experimental results from predicted optimum conditions. This report showed that simultaneous optimization of the production of ARA and EPA by M. alpina CBS 528.72 on date waste can be achieved by modification of process variables in solid-state fermentation.
Keywords: Mortierella alpina; arachidonic acid (ARA); date waste; eicosapentaenoic acid (EPA); experimental design; solid-state fermentation.