Variation in the phytochemical contents and antioxidant activity of Glycyrrhiza glabra populations collected in Iran

Glycyrrhiza glabra (Fabaceae) is a perennial herb including valuable and commercial constituents such as glycyrrhizic acid and glabridin which has attracted the attention of food and pharmaceutical industries. In the present study, a variation on the phytochemical and antioxidant activity of 22 populations of valuable and profitable medicinal plant Glycyrrhiza glabra (licorice) was investigated. We expanded our approach by using geographic information system (GIS) to predict the potential areas for licorice cultivation in Iran. Outstanding quantitative variability of glycyrrizic acid, glabridin, liquiritin and liquiritigenin content were observed in the cork and fleshy texture of root of licorice populations from different regions of Iran. The maximum and minimum amount of glycyrrhizic acid was observed in Bajgah (74.00 mg/g dry weight) and Taft (13.43 mg/g dry weight) populations, respectively. The greatest amount of glabridin content was recorded in Kashmar population (12.88 mg/g dry weight). Also, the greatest antioxidant activity (the lowest IC50) for licorice root was associated to Kashmar, Meshkin shahr and Eghlid populations with IC50 equal to 44.4, 56.5 and 59.5 mu g/ml, respectively. Moreover, Kazerun, Taft and Ahar populations had remarkable antioxidant activity in a methanolic extract of aerial part. Consequently, frequency ratio (FR) model was run to mapping the habitat suitability of Glycyrrhiza glabra based on annual average temperature, average yearly precipitation and altitude.