The antimicrobial activity of methanolic extracts of Ziziphus spina-christi leaves were examined by using agar well diffusion method against five bacteria Staphylococcus
aureus (ATCC653-8), Pseudomonas aeruginosa MTCC2453, Bacillus cereus (ATCC6633), Escherichia coli MTCC739, Staphylococcus epidermides(local isolate) in addition to Candida albicans (ATCC2019). The results indicated that the Ziziphus spina-christi leaves methanol extract is effective against tested gram positive bacteria in addition to Candida albicans at all concentration used(50 mg/ml to 300 mg/ml) while don’t have any effect against tested gram negative bacteria. In general, all concentration used given an effect on the gram positive bacteria only. The highest inhibition zone given by the high concentration of Ziziphus spina-cristi acetone extract 300 mg/ml on Bacillus cereus. While the lower inhibition zone given by third concentration 100 mg/ml against B.cereus. The results of the DPPH scavenging activity of methanol extract possess high antioxidant activity at different concentrations with IC50 value equal to 166.4698 ug / ml compared to the IC50 value of control sample (L-Ascorbic acid) that equal to 145.8838 ug / ml .
Mofeed Al-Nowihi, Al-Husami and Rasheed HM