Integrated analysis of the transcriptome, metabolome and analgesic effect provide insight into potential applications of different parts of Lindera aggregata

Lindera aggregata (L. aggregata) is a wild shrub growing in the forests of Southeast Asia, whose main bioactive constituents are isoquinoline alkaloids. They are widely used in food and pharmaceutical industries. The studies on the metabolites and biosynthesis pathways in L. aggregata remain poorly understood. Nine isoquinoline alkaloid compounds were identified by UPLC Triple TOF-MS/MS in this study. Except for N-methyllaurotetanine, most isoquinoline alkaloid compounds were widely distributed in various parts of L. aggregata and accumulated preferentially in roots than in leaves. Transcriptome data showed that several isoquinoline alkaloid biosynthetic genes, such as TyrAT, PPO, TDC, and SOMT, were identified to play important roles in generating differential metabolites in roots and leaves of L. aggregata. Concentration-dependent analgesic effects and toxic effects of them were demonstrated in zebrafish experiments, and the overall ranking was JRAL > TRAL > LAL. The results of this study would provide useful information for the synthesis mechanisms of isoquinoline alkaloids in L. aggregata, and provide valuable information for the application of traditional non-medicinal parts of L. aggregata in food and pharmaceutical industries.