Mutagenesis treatment of Mortierella alpina for PUFA production enhancement for future food development

• Mutagenesis as a key tool for improving fungal strains for future food development • 5-fluorouracil concentration and exposure time impact arachidonic acid content (ARA) • ARA and PUFA content in isolate M5F047 were 2 times that of the M. alpina wild type • M5F047 is a promising additive in plant-based meats to improve the meaty flavour Random mutagenesis has been identified as a key tool for improving microbial and fungal strains enabling the development of isolates with improved traits suited for industrial scale metabolite production to enhance the nutritional value of future foods. Presented here, is a random mutagenesis strategy employed to assess the effect of 5-fluorouracil (20-200 µg/ml), alone and in combination with the secondary agents octyl gallate and nocodazole, and diethyl sulfate (0.1 to 1 %) chemical mutagenic agents, on the biomass and lipid production as well as the FAME profile. Interestingly, a correlation was demonstrated between 5-fluorouracil exposure time and the arachidonic acid content, which was also influenced by the concentration used. 5-fluororuracil of 100 µg/ml treatment for 48 h resulted in the highest arachidonic acid (% TFA) content in isolates. Mutant M5F047 isolated with 5-fluororuracil (100 µg/ml) alone, proved to be most superior in terms of polyunsaturated fatty acid (PUFA) and arachidonic acid production, as compared to the Mortierella alpina wild type strain, with enhancements that doubled that of the parent strain. These improvements are more favorable for industrial scale production of arachidonic acid, a precursor of meaty flavour to improve plant-based meats in future food development.