Antibacterial and antioxidant activities of ethanol extracts of some plants selected from South Jordan

Abstract

Three Jordanian medicinal plants; Peganum harmala (P. harmala), Geropogon hybridus (G. hybridus), and Salvia officinalis (S. officinalis) were selected from Al-karak region in order to investigate their antibacterial and antioxidant activities. The crude extract yield of all used plants were varied from 10.6% in Salvia officinalis and 15.6% in P. harmala, to 18 % in G. hybridus. The antibacterial activity of these plants was carried out on four bacterial strain (S. aureus, E.coli, E. aerogenes and B. subtilis). These plant ethanol extracts have effects on the gram positive strains and gram negative bacteria except S. officinalis did not show activity against E. Coli. The minimal inhibition concentration (MIC) of P. harmala S. officinalis and G. hybridus (MIC) ranged from 125 µg/ml to 500 µg/ml. The ethanol crude extract of G. hybridus gave 10 fractions using TLC method, fraction 1,3 and 10 exhibited antibacterial activity against all bacterial strains. Their total phenolic contents were evaluated; the highest total phenol content was observed in G. hybridus with 410 mgGAE/g plant extract followed by P. harmala and S. officinalis with 305 and 203.7 mg/g plant extract, respectively. The antioxidant activity was estimated by using DPPH method. The highest antioxidant activity was obtained with G. hybridus extract and found to be 0.89 mg Trolox/g plant extract. The lowest antioxidant activity was obtained with S. officinalis which was 0.53 mg Trolox/g plant extract. The lowest IC50 (highest antioxidant activity) was observed in G. hybridus with 0.83 mg/ml. Intermediate effect observed in P. harmala with IC50 1.1 mg/ml. The lowest antioxidant activity was obtained in S. officinalis with IC 1.38 mg/ml.