Lipidomic profiling of Pleurotus ostreatus by LC/MS Q-TOF analysis

In this paper, for the first time a lipidomic analysis on Pleurotus ostreatus species was performed by liquid chromatography quadrupole time-of-flight mass spectrometry (LC/MS Q-TOF). Twenty-seven lipid classes, including polar and non-polar lipid classes, were detected. Free fatty acids (FA) were the predominant fraction (>57%), followed by fatty acid ester of hydroxyl fatty acid and ceramide. C18 chain length and two double bonds were the main structural characteristics for FA. Phosphatydilcholine, phosphatydiletanolamine, and glycer-ophosphates showed high percentages of polyunsaturated fatty acids. Unconventional fatty acids, such as odd and oxygenated chains, were detected. The highest odd/even ratio was found in hexosylceramides and sphin-gomyelin, while oxygenated chains were mainly represented in ceramides. As a preliminary approach, the results of lipid molecular species, subjected to principal component analysis and discriminant analysis, were able to differentiate P. ostreatus samples on the base of grown substrate. The results of the comprehensive analysis of P. ostreatus lipids are useful to evaluate the lipid nutritional value and could facilitate exploitation of P. ostreatus consumption.