Journal of food science and technology(Iran)

Journal of food science and technology(Iran)

Antimicrobial Susceptibility of Bacillus Cereus Isolates from Different Infectious Sources

Document Type : Original Article

Authors
Moammal F. Hawad 1
Mohsin Hashim Risan 2
Malika alili 3
Muntadher Mahmood Abo-Hailah Abo-Tabikh 4
1 Department of applied biological science, College of biotechnology, Al-Nahrain University, Baghdad, Iraq.
2 2Department of applied biological science, College of biotechnology, Al-Nahrain University, Baghdad, Iraq.
3 3Department of Natural Sciences, Ecole Normale Supérieure de Kouba (ENS Kouba), B.PN°92 16308 Algiers, Algeria.
4 Department of Soil Sciences and Water Resources, College of Agriculture, University of AL- Qadisiyah, Iraq.
10.48311/fsct.2026.120085.83112
Abstract
The study aimed to evaluate and compare the susceptibility of Bacillus cereus isolates to antimicrobials isolated from a variety of locations in Iraq. 120 samples, consisting of 20 clinical and 100 food-derived samples. The samples were cultured on Nutrient Agar, Blood Agar and Polymyxin Pyruvate Egg Yolk Mannitol Bromothymol Blue Agar (PEMBA) medium, and the final confirmation of the B. cereus isolates were performed using the VITEK® 2 system. representative clinical and food isolates were compared against a group of antimicrobials using the disk diffusion method according to the CLSI M45 A3 2024 standards. The distribution of the inhibition zones. The food isolates had the greatest level of susceptibility to the antibiotics tested (39.83% susceptibility to carbapenems, followed by 27.12% susceptibility to fluoroquinolones). All the other antibiotics showed less than half the level of inhibition (glycopeptides 11.44%; aminoglycosides 11.02%; tetracyclines 10.59%). In contrast to the food derived strains, the clinical isolates showed lower levels of inhibition than found in all tested food derived strains (32.10% susceptibility to carbapenems and 29.63% to fluoroquinolones), with both aminoglycosides and tetracyclines having 12.96% respectively and glycopeptides 12.35%. Both the food derived and clinical strains exhibited 100% level of intrinsic resistance (0.0%) to trimethoprim. The study provided data indicating there are substantial differences between the efficacy of several classes of antimicrobial agents against B. cereus.
Keywords
: Bacillus cereus
Antimicrobial susceptibility
VITEK 2
Food borne
Subjects
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