Comprehensive transcriptomic and metabolomic analyses of one-year-old and two-year-old Polygonatum cyrtonema Hua

Polygonatum cyrtonema Hua is a traditional Chinese herbal medicine. It is rich in polysaccharides, flavonoids, alkaloids and other medicinal active ingredients, which plays an important role in maintaining human health. Because P. cyrtonema is a perennial plant, the cultivation time may affect the accumulation of functional active ingredients in the body. In purpose to explore the differences in the level of secondary metabolites, we used non-targeted metabolomics (LC-MS) technology to study the root tissues of 1-year-old and 2-year-old P. cyrtonema . Metabolomics results showed that the differential metabolites were enriched into 77 metabolic pathways, and the significantly enriched pathways were related to amino acid biosynthesis and carbohydrate metabolism. At the same time, phenylalanine, citric acid, cinnamic acid and other metabolites accumulated more in 2-year-old plants. Furthermore, transcriptome analysis showed that a total of 2068 differentially expressed genes (DEGs, 1026 up-regulated genes and 1042 down-regulated genes) were identified, and 102 metabolic pathways were enriched, among which glucose metabolism, phenylpropanoid biosynthesis and flavonoid biosynthesis were highly enriched metabolic pathways. These analysis results display that with the increase of cultivation time, the metabolic pathways of related active substances will be enhanced accordingly. Generally speaking, this study applied multi-omics techniques to show the differences in metabolites and gene levels of P. plants with different growth years, which will provide valuable clues for finding candidate genes involved in the biosynthesis of active substances.