A multi-omics-based investigation into the regulation of phenolics in fresh maize kernels at different developmental stages

In this study, a total of 33 key differential metabolites related to phenolic synthesis were obtained in the fresh-eating and maturity stages by LC-MS analysis using UNIFY with a self-constructed database. Based on KEGG pathway analysis, three pathways related to phenolic metabolite synthesis were identified. The differential genes selected from the transcriptome and the differential metabolites selected from the target metabolism were correlated in the analysis, revealing the existence of 7 enzymes involved in the synthesis of phenolic compounds in secondary metabolism. Among which the fresh-eating stage promotes phenolics synthesis by up-regulation of the activities of the two enzymes, CCoAOMT and 4CL, and the enzymes, DFR, C3H, DFR, CHI, REF1 and F3H were expressed at higher levels during the maturity stage than fresh-eating stage, thus improving the tolerance and stress resistance of the plant itself and its ability to respond to the external environment, which has an important impact on the regulation of phenolic accumulation.