| ORIGINAL ARTICLE |
|
|
|
Antimicrobial resistance is currently one of the most public health serious concerns because of the overuse and unsuitable use of antibiotics. Therefore, this study was conducted to evaluate the resistance patterns of five Bacillus species including B. subtilis, B. atrophaeus, B. amyloliquefaciens, B. simplex and B. tequilensis in vitro towards antibiotic on NA media. The inhibition of Bacillus growth was detected after 72 hours of incubation. The obtained data indicated that Bacillus resistance to antibiotic was species-related as B. subtilis, (N = 19; % 94.74), B. amyloliquefaciens, (N = 11; % 90.91), and B. atrophaeus (N = 3; % 0), B. simplex (N = 2; % 0) and for B. tequilensis (N = 3; % 66.6) towards Cefazolin. Most of the Bacillus strains were resistant against Cefazolin (79%), Tobramycin (16%), Pefloxacin (11%), and Gentamycin (11%), whereas no resistance was shown against Levofloxacin and Nitrofurantoin. The percentage of zone inhibition of the Bacillus ssp. colonies (in mm diameter) ranged from 0 to 60 mm, compared to the untreated control. The present work has demonstrated species-specific differences in the antimicrobial susceptibility of Bacillus spp. and observation Bacillus resistant strains is of alarm about how this resistance could spread to other bacteria, and then to humans.
Key words: Antimicrobial resistance, Bacillus species, inhibition zone
