Influence of ecological conditions on some secondary metabolites variations in Moroccan Juniperus thurifera stands

Abstract

The aim of this work is to study the influence of ecological conditions on some secondary metabolites (phenols and flavonoids) in 14 Juniperus thurifera stands collected from the High and the Middle Atlas Mountains of Morocco. Total phenol and flavonoid contents were determined spectophotometrically using Folin-Ciocalteu and AlCl 3 reagents, respectively. The antioxidant activity of the methanolic extracts was examined by DPPH method. The total phenol contents ranged from 137 mg GAE/g DW (in Bouiblan) to 191 mg GAE/g DW (in Tizrag). The total flavonoid contents ranged from 11 mg QE/g (in Bouiblan) to 28 mg QE/g (in Tizrag). The highest antioxidant activity was noticed in Tizrag and the lowest was noticed in Bouiblan. These results showed a positive correlation between phenols, flavonoids and antioxidant activity. Comparison between the Middle and the High Atlas stands showed significant differences between stands. The Middle Atlas stands are statistically close but those of the High Atlas are statistically different.