Relationships between the bioactive compound content and environmental variables in Glycyrrhiza uralensis populations in different habitats of North China

The content of active compounds in Glycyrrhiza uralensis may vary among populations in different regions, and be influenced by environmental variables. We determined the effects of soil and climate on contents of glycyrrhizic acid and liquiritin in various populations of Glycyrrhiza uralensis. Fifty individuals from 5 range-land populations in arid and semi-arid regions of North China were collected and analyzed. The contents of glycyrrhizic acid and liquiritin were determined using the HPLC method. Contents of glycyrrhizic acid and liquiritin varied significantly among populations as follows: Chifeng > Hangjinqi > Minqin > Aletai > Kashi. These contents were significantly correlated with soil nutrients (e.g. P, K, N), organic matter, and annual precipitation. However, soil P and K, and precipitation were the key factors influencing the contents of active compounds. Environmental variables can be useful to predict the contents of glycyrrhizic acid and liquiritin in Glycyrrhiza uralensis.