Comprehensive characterization of volatile terpenoids and terpene synthases in Lanxangia tsaoko

Lanxangia tsaoko is widely utilized in human cuisine as a popular flavoring agent due to its distinctive aroma. It also has a long history of use in traditional Chinese medicine. The edible and medicinal properties of L. tsaoko are primarily attributed to its diverse array of volatile metabolites. Previous research has mainly focused on classifying the constituents and their pharmacological activities in L. tsaoko, leaving gaps in comprehensive identification and elucidation of the biosynthetic mechanisms of these metabolites. In this study, we employed a multi-omics approach and functional characterization to investigate the biosynthesis of volatile terpenoids in L. tsaoko. The results demonstrated that terpenoids constituted the highest proportion of volatile compounds in L. tsaoko. Additionally, 42 terpene synthase (TPS) coding genes were identified through genome-wide analysis. Functional characterization revealed that eight LtTPSs effectively catalyzed geranyl pyrophosphate to produce monoterpenoids, while four LtTPSs converted farnesyl pyrophosphate to generate sesquiterpenoids. Genome-wide and single-gene duplication events contributed to functional diversification among LtTPSs with high identity, promoting the diversity of terpenoids. These findings provide a foundation for understanding the biosynthesis of volatile terpenoids in L. tsaoko, enhance the current knowledge of TPS, and contribute to the broader understanding of the biochemical diversity of terpenoids in plants.