Evaluation of Antibiotic Resistance in Escherichia coli Strains Isolated from Pastry Cream in Hamadan, Iran

Abstract

Background: Escherichia coli is one of the most important intestinal pathogens, which is transmitted to humans through food and has significant effects on the quality of food products, including pastry cream. Its presence in food is considered an indicator of fecal contamination. Objectives: This study aimed to determine the prevalence and pattern of antibiotic resistance of Escherichia coli in pastry cream prepared in Hamadan, Iran. Methods: The pastry cream samples (n, 350) were randomly purchased from confectionery suppliers, located in different districts of Hamadan. Forty-seven out of 350 samples contained E. coli. The bacteria were identified after culturing the samples in a nutrient-broth-enriched medium and solid media, such as violet red bile agar (VRBA), eosin methylene blue (EMB), and nutrient agar (NA), to identify bacteria isolated by the linear method. The samples were then incubated at 37°C for 24 to 48 hours. Results: The results of antibiotic tests showed the highest resistance to tetracycline, vancomycin, oxacillin (100%), and penicillin (72.34%) and the highest sensitivity to chloramphenicol (78.23%), ciprofloxacin (76.59%), and nalidixic acid (61.70%). Conclusions: According to the present findings and similar research from Iran, the rate of E. coli resistance to antibiotics is high. To avoid the contamination of pastry cream by these bacteria, some techniques, including cold chain management, employee personal hygiene, use of healthy raw materials, and proper thermal processes, should be adopted.