Lanthanum Enhances Biomass and Bioactive Metabolite Production in Glycyrrhiza uralensis via Coordinated Gene Regulation

Yuanyang Shao¹Yushi Wang¹Yunhao Zhu²Lei Wang³Yashun Wang¹Xingyu Guo¹Enai Zhai¹Huiqin Zou¹Yonghong Yan^1*

• ¹Beijing University of Chinese Medicine, Beijing, China
• ²Henan University of Chinese Medicine, Zhengzhou, China
• ³Henan Luoyang Orthopedic Hospital, Luoyang, China

Glycyrrhizic acid, liquiritin, and liquiritigenin are key secondary metabolites in Glycyrrhiza uralensis Fisch with significant pharmacological value, yet their relatively low content poses a challenge. To enhance their production, this study investigated the promotive effect and mechanism of the rare earth element lanthanum (La). The impact of La treatment on Glycyrrhiza uralensis was systematically evaluated by measuring biomass parameters (plant height, root fresh weight, root dry weight), metabolite content (UPLC-MS/MS), and the expression levels of key biosynthetic genes (transcriptomics). Results showed that La treatment significantly promoted plant growth (increased biomass parameters) and enhanced the accumulation of secondary metabolites (glycyrrhizic acid, liquiritin, liquiritigenin). Concurrently, La markedly upregulated the expression of key genes in the glycyrrhizic acid pathway (SQE, CYP88D6) and the liquiritin/liquiritigenin pathway (PAL, C4H, CHS, 4CL). Significant positive correlations were observed among La-induced biomass increase, metabolite enhancement, and upregulation of these key genes. Mechanistically, La exerts a dual regulatory effect: it increases the biomass accumulation of precursors for metabolite synthesis while simultaneously upregulating the expression of key rate-limiting enzyme genes (SQE, CYP88D6, PAL, C4H, CHS, 4CL) in the biosynthetic pathways, ultimately synergistically promoting the accumulation of glycyrrhizic acid, liquiritin, and liquiritigenin. This study elucidates the mechanism by which La enhances the accumulation of major secondary metabolites in Glycyrrhiza uralensis, providing a novel strategy for utilizing rare earth elements to boost the yield of bioactive compounds in medicinal plants.