Antimicrobial Activity and Allelopathic Potential of Zygophyllum coccineum L. on Chenopodium album L.

Zygophyllum coccineum L. (Family Zygophyllaceae) was collected from two locations namely Wadi Hagul and Deltaic Mediterranean coast. Methanol, acetone and ethanol extracts prepared from Z. coccineum leaves and they were tested for their antibacterial activity. The bacterial strains tested were Escherichia coli, Bacillus subtilis, Staphylococcus aureus, Bacillus cereus, and Pseudomonas aeruginosa. Methanol extract from desert plant was the most potent extract against bacterial growth compared with other extracts. Also, the three extracts expressed antifungal activities against the tested fungi Candida albicans, Aspergillus niger and Aspergillus flavus. Methanol extract from the desert plant was the strongest in retarding the fungal growth. The aqueous leaf extract of Z. coccineum from both desert and coastal areas inhibited seed germination and radical growth of Chenopodium album at 50 and 100 µgml-1. The inhibition rate was remarkable with the desert plant compared to that of coastal one and this may be due to the higher contents of bioactive compounds.