Multi-dimensional "projection" - the impact of abiotic stresses on the content of seven active compounds and expression of related genes in Glycyrrhiza uralensis Fisch

Triterpenoids and flavonoids from licorice (Glycyrrhiza uralensis Fisch.) are known to have a wide range of applications in the pharmaceutical, skin care, and food industries. The effects of various types of abiotic stresses and associated phytohormones - polyethylene glycol, sodium chloride, ultraviolet, cadmium, abscisic acid, and methyl jasmonate - on both the content of these secondary metabolites and the transcript levels of genes encoding enzymes of important biosynthetic pathways were evaluated in hydroponic seedlings of G. uralensis. In these treatments, abscisic acid induced a substantial increase in the levels of the four active compounds, compared to the control. Analysis of the expression of genes involved in the biosynthetic pathways of these compounds, such as FPPS, showed that their transcript levels were significantly up-regulated in the four stresses. These findings suggested that the multi-stress superposition pattern of the content of active compounds and the gene expression of their biosynthetic pathways may provide insights to explore the management of secondary metabolite synthesis pathways in medicinal plants. It could facilitate a better understanding of the formation patterns of active compounds in licorice in artificial cultivation. Further insights may also be provided to increase the yield of these high value components.