Two Gram-positive bacteria [Streptococcus pyogenes (S. pyogenes)
and Staphylococcus haemolyticus (S. haemolyticus)], two
Gram-negative bacteria [Salmonella typhi (S. typhi) and Pseudomonas
aeruginosa (P. aeruginosa)] and fungal yeast [Candida
tropicalis (C. tropicalis)] were used in this study. The microbial
strains were obtained and confirmed at the Department of Botany
and Microbiology, Faculty of Science, Helwan University. The
concentrations of the bacterial crude extracts were adjusted to
50 mg/mL. The antimicrobial activities were performed by using
disk diffusion method [17]. Chloramphenicol (10 mg/disc) and
ampicillin (5 mg/disc) were used as positive controls. The activity
was determined by measuring the diameter of the inhibition
zones in millimeters.