Polyphenolic extract and essential oil quality of Thymus zygis ssp. gracilis shrubs cultivated under different watering levels

摘要: Abstract Thymus zygis ssp. gracilis shrubs were cultivated as an experimental crop under different watering level, in order to achieve 81, 63, 44 and 30% of the local potential evapotranspiration (ETo). After 4 years cultivation, thyme leaves analyzed on basis their essential oil (yield quality), total phenolic content, free radical-scavenging activity polyphenolic profile. Essential yield values ranged between (2.3 ± 0.7) (3.6 ± 0.7)% for 81 ETo equivalent, respectively. The comparison production at 2nd 4th cultivation showed that using levels higher than equivalents reduced significantly (P  Analysis profile, radical scavenging performed post-distillation dry leaves. Total content from (122.2 ± 19.3) (108.5 ± 19.2) mg gallic acid (GAEs)/g plant highest lowest level treatment, Regarding rosmarinic acid, followed by apigenin, ferulic, carnosic caffeic acids, was component quantified concentrations. Radical-scavenging activities (IC50) concentrations varied (3.7 ± 1.6) mg/mL 81% (7.4 ± 2.3) mg/mL ETo. In spite intra-specific variability detected, individual analysis has allowed selection plants which are characterised having adequate extract almost all them being a 60% level. These selected will allow us make further vegetative propagations obtain homogeneous field crops with contrasted quality