Lipidomic analysis revealed dynamic changes of lipidic compounds of postharvest strawberry in response to gray mold

Lipidomics enables high-throughput screening of lipidic compounds in biological samples that is potential to reveal the molecular mechanism from the perspective of lipidic metabolism and to discover potential biomarkers. Current study applied lipidomic analysis to unveil the lipid-associated bioprocesses in postharvest strawberry-gray mold interaction. Five extraction methods were candidates for optimization of strawberry lipid enrichment, and dichloromethane extraction was selected. Among 114 commonly detected lipids in mock and inoculated groups, glycerophospholipids were the most abundant followed by fatty acids. Total 35 lipids that were differentially expressed in mock and inoculated groups which were clustered into 6 groups with various trends. Wherein, 12 differentially expressed lipids were found distinct trends in mock and inoculated groups. Coordinately, 53 of 121 lipidic compounds, which were only detected in inoculated group, were highly correlated with the necrotrophic phenotype. Combined with hemibismonoacylglycerophosphate 54:7| hemibismonoacylglycerophosphate 18:2/18:2_18:3, triacylglycerol 54:9| triacylglycerol 18:3_18:3_18:3, 53 lipids only detected and highly correlated in inoculated groups and 12 differentially expressed lipids, each of these 67 lipids was able to be biomarker of strawberry gray mold. Beside metabolism of glycerolipid and glycerophospholipid, biosynthesis of secondary metabolites and autophagy are also enriched pathways associated with variated expression of related genes. This study provided molecular evidence of the significance of lipidic compounds in strawberry at postharvest stage, and the discovery of biomarkers facilitated the early detection of strawberry gray mold as well as the discovery of lipidic anti-gray mold reagents or supplements.