Arachidonic Acid Production by Mortierella alpina on Brewery Spent Malt Enriched with Vegetable Oils Using Solid-State Fermentation
Year: 2026
Type: article
Abstract: Arachidonic acid (AA) is a high-value long-chain polyunsaturated fatty acid commonly produced by submerged fermentation of oleaginous fungi. Solid-state fermentation (SSF) using low-cost agro-industrial by-products represents a promising alternative approach for sustainable microbial lipid production. In this study, spent malt, a by-product of the brewing industry, was evaluated as a solid substrate for AA production by Mortierella alpina under SSF conditions. Four M. alpina strains were screened for growth, lipid accumulation, and AA production, and M. alpina 959 was selected as the most promising strain. The effects of nitrogen supplementation and oil incorporation on biomass formation, lipid accumulation, and AA productivity were subsequently investigated. Sunflower oil incorporation into spent malt-based substrates improved AA productivity under the most favorable conditions, resulting in an AA proportion of 38.6% of total fatty acids and 102.5 mg AA g−1 of final dry mass of the SSF system (FDW-SC). Comparison of selected vegetable oils further demonstrated that the lipid source affected AA production, while having only a limited effect on fungal growth and total lipid accumulation. Overall, this study demonstrates the feasibility of spent malt-based SSF for AA production by M. alpina and highlights the valorization of brewery spent malt as a low-cost agro-industrial by-product for the production of value-added microbial lipids.
Source: Fermentation
Institutions: National Agricultural and Food Centre, Biorealis (Slovakia)
Language: English
Subfield: Molecular Biology
Domain: Life Sciences
Open Access status: gold
Estimated APC paid: $2,534
OpenAlex ID: W7204125488