Enhancing antibacterial efficacy and reducing the risk of antibiotic resistance of food-borne pathogen Cronobacter sakazakii by integrating essential oils with silver nanoparticles and antibiotics

Abstract

Cronobacter sakazakii is known as a food-poisoning bacterium that can withstand stressed environments. This study highlights the urgent need for effective antimicrobial alternatives by examining the emergence of antibiotic-resistant C. sakazakii in Egyptian dietary foods and the effects of essential plant oils and silver nanoparticles. The antibiotic susceptibility profiles of the fifteen C. sakazakii-positive samples were assessed using ten distinct antibiotics. Furthermore, a well diffusion method is used to estimate the minimum inhibitory concentrations of essential oils and silver nanoparticles. Scanning electron microscopy was also used to examine the morphological changes of the powerful antibiotic-resistant strain. Ipenem, ampicillin sulbactam, gentamicin, cefotaxime, ciprofloxacin, amikacin, ceftriaxone, and streptomycin were all resistant to C. sakazakii isolates, with a 100 % resistance incidence. They showed intermediate resistance to trimethoprim/sulfamethoxazole (80 % resistance incidence) and were only sensitive to norfloxacin (26.6 % resistance incidence). Essential oils (12–45 mm) were more successful in suppressing C. sakazakii than susceptible antibiotics (10.83–14.17 mm) and silver nanoparticles (7.17–12.25 mm). Higher inhibitions were provided by mint and basil oils, with mint oil exhibiting the best performance at 45 mm. The combination of antibiotics, silver nanoparticles, and essential oils demonstrated synergistic effects against powerful bacteria. Compared to clove + mint with trimethoprim/sulfamethoxazole (40 mm) or silver nanoparticles with basil oil (35 mm), mint-infused silver nanoparticles showed higher inhibition (45 mm). After being treated with basil oil, C. sakazakii showed morphological changes as seen by scanning electron microscopy. Combining essential oils with antibiotics and silver nanoparticles offers a viable way to counteract C. sakazakii's growing threat. In a medical environment that is becoming more complex, these developments offer hope for improving patient outcomes and safeguarding public health.