Metabolic profiling provides insights into the accumulation patterns of flavonoids and phenolic acids in different parts of Lactuca indica L.

Lactuca indica L. contains high amounts of flavonoids and phenolic acids. However, there is limited information on the composition of these compounds in different parts of the plant. The present study analyzed the secondary metabolite profiles of the stem, leaf, flower, and seed of Lactuca indicaL.cv. Mengzao (LIM) using a widely targeted metabolomic approach. A total of 576 secondary metabolites were identified, including 218, 267, 232, 286, 302, and 308 differentially accumulated metabolites (DAMs) in the stem_vs_leaf, stem_vs_flower, stem_vs_seed, leaf_vs_flower, leaf_vs_seed, and flower_vs_seed comparisons. In particular, considerable differences were detected in the flavonoids and phenolic acids, five flavonoids, five phenolic acids, one triterpenoid and one alkaloid being differentially accumulated in the four parts. Compared to the stem and flower, the leaf and seed had higher total flavonoid content and total phenolic content. Thses findings provide comprehensive insights into utilizing different parts of LIM in developing functional food products.