In Vitro Screening of Antibacterial Properties of Rhus coriaria and Origanum vulgare against Some Pathogenic Bacteria

This study investigates the antibacterial property of Rhus coriaria (Sumac) and Origanum vulgare (Jatra) aqueous extracts against Escherichia coli ATCC 25922, Klebsiella pneumoniae, Proteus mirabilis and Pseudomonas aeruginosa ATCC 27835. Results confirm the resistance of the bacterial isolates against more than three antibiotics. The aqueous extract of R. coriaria showed the highest activity as an inhibitor against tested bacteria, while the aqueous extract of O. vulgare shows low effect against the above mentioned bacteria. MIC for R. coriaria and O. vulgare aqueous extracts were determined for four bacterial isolates. The MIC of O. vulgare against tested bacteria was >12%, while the MIC of R. coriaria was 4% for E. coli, <0.025% for both K. pneumoniae and P. mirabilis and 2% for P. aeruginosa. The phytochemical groups of both plants extract were analyzed; the results indicated both plants contain tannins, phenols and saponins, flavonoid, alkaloid, and phlobatanin. The antimitotic effect of both plants extracts were investigated on Allium cepa, and the extracts showed inhibitory role in the root growth in contrast to the control when grown in the tap water for 5 days. In addition, the 24 hours treatment of grown roots in tap water with both extracts resulted in significant decrease in mitotic index.