Analysis of fatty acid esters of hydroxy fatty acids in edible mushrooms

Edible mushrooms are consumed worldwide. The overall amount of lipids in mushrooms is small and consists of complex lipids, such as triacylglycerols, phospholipids, and sterols. Nutritional studies have outlined the lipid compositions of mushrooms but have not analyzed their fatty acid esters of hydroxy fatty acid (FAHFA) profiles. FAHFAs are a class of anti-inflammatory and antidiabetic lipids frequently found in human food. This study aimed to characterize the FAHFA profiles of various edible mushrooms. Using a liquid chromatography-mass spectrometry-based lipidomics approach, we identified 34 FAHFAs in seven members of the fungal order Agaricales, also known as gilled mushrooms. Linoleic acid (LA)-containing FAHFAs were the most abundant among all the species. Shiitake (Lentinula edodes) and enokitake (Flammulina velutipes) mushrooms showed the most divergent FAHFA profiles, being rich in short-chain FAHFAs and very long-chain FAHFAs, respectively. The brown (Hypsizygus tessulatus) and white (Hypsizygus ulmarius) varieties of shimeji have closely related FAHFA compositions and quantities of FAHFA diversity can be used for chemotaxonomic classification of the mushroom family, similar to mitochondrial (mt)DNA information. Adding mushrooms to the diet provides several micronutrients, including FAHFAs, with minimal impact on the overall calories from fat.