الأنشطة المضادة للميكروبات ومضادات الأكسدة والسمية للخلايا لنبات الإيفيدرا أفيلا وباسيا موريكاتا من شمال الأردن.

The current study has been conducted to investigate the antimicrobial, antioxidant and cytotoxic potential of Ephedra aphylla and Bassia muricata extracts prepared in different solvents; methanol, ethanol and mixed solvents (methanol: chloroform: water (12:5:1)). In this study, antimicrobial activity against some selected bacteria and fungi using agar well diffusion method at different concentrations (50, 100, 150 and 200 mg/ml) were investigated. Also, different combination with different ratios of plant extracts was used. Antioxidant activity of plant extracts was assessed using 2, 2-diphenyl-1-picrylhydrazyl (DPPH) assay. Cytotoxic effect of plant extracts was evaluated using 3-(4, 5-dimethylthiazolyl-2)-2, 5-diphenyltetrazolium bromide (MTT) assay. Extracts were tested in vitro for their antimicrobial activity against Gram positive bacteria (Bacillus subtilis and Staphylococcus aureus), Gram negative bacteria (Pseudomonas aeruginosa and Escherichia coli), and fungi (Aspergillus niger and Candida albican). The highest activity of E. aphylla found in all extracts at concentration of 200 mg/ml with inhibition zones of 14?1.15 mm against P aeruginosa. For B. muricata, all extracts showed high activity at the concentration of 200 mg/ml against B. subtilis with inhibition zones of 20?2.02 mm. The plant extracts showed antifungal activity against C. albicans but there was no activity against A. niger. Four different concentrations (1, 2, 3 and 4 mg/ml) of plant extracts were evaluated for their antioxidant potential. Results showed that the antioxidant activity increases with the increase of concentrations and incubation time. It was shown that the extracts of E. aphylla and B. muricata had a significant DPPH radical scavenging activity which may be due to the presence of phenolic components. The extracts of B. muricata showed higher scavenging activity than the extracts of E. aphylla. This may happen due to the variation in the levels and profiling of secondary metabolites in these extracts with antioxidant properties. Based on that, it was concluded that E. aphylla and Al-Barri et al. 48 B. muricata could be a good source of natural antioxidants. The cytotoxic effect of plant extracts was evaluated using human lymphocyte cells and Chinese hamster ovary cells (CHO). The results showed that the extracts increase cell viability and had no toxicity against these cells and this is probably due to nutrient that these plants possess. Further studies on the antimicrobial potential of these plant extracts on other multidrug resistant microorganisms are recommended. Extraction and purification of biologically active ingredients from these plant also recommended.