Abstract
Background: Marine-derived fungi are an underexploited source of lipids for health and nutrition. Little is known about the impact of sugar type on the lipid diversity produced by a marine-derived fungi.
Objective: Traditionally glucose is used as the main sugar source for fungal growth. Thus, this study aimed to reveal the glycolipid alteration induced by glucose replacement by galactose. Methods: The marine-derived Acremonium sp. MMS540 fungal strain was cultivated on three different media with for each the use of glucose or galactose as sugar source, using an OSMAC (One Strain Many Compounds) strategy. For the six different culture conditions, the total lipid and lipid class content of the fungal extracts were evaluated. Fatty acids composition was determined by GC-MS. Finally an LC-MS lipidomic approach was used to evaluate glycolipid modification induced by this sugar replacement. Results: The replacement of glucose by galactose did not alter drastically the total lipid production. However, their GC-MS profiling reveal major modification in the main detected fatty acid ratio (Δ 916:1, 16:0, Δ 9-1218:2, Δ 918:1, 18:0) with a decrease of the minor fatty acids diversity. Complementarily, the LC-MS profiles revealed that in the case of Acremonium sp. MMS540, this culture medium modification alter lipid and glycolipid chemical diversity. Conclusion: This study revealed the link between the sugar uptake in fungi and the associated glycolipid production. This emphasis that very minor changes may drastically alter not only the secondary natural products in fungi but also its lipid related production.Keywords: Acremonium, fatty acid, glycolipid, lipid, lipidomic, oleaginous fungus, OSMAC approach.
Graphical Abstract