Research Article
Aboubaker M Garbaj, Said K Abo
Abstract
Background: Cronobacter sakazakii is associated with illness in infants from contaminated powdered infant formula (PIF) and it is frequently recovered from PIF factory environment. Limited information is available on contamination of other food such as dairy and meat products in Libya. Methods and findings: A total of 261 samples of milk, dairy products and coarse ground meat products were collected from different localities in Libya. Samples were examined for Cronobacter spp. with an adapted ISO /DTS 22964 cultural protocol using HiChrome™ Enterobacter sakazakii modified agar coupled with 16S rDNA partial sequencing to identify the organism. The identified isolates were biochemically characterized and tested for their ability to produce yellow pigment. Out of the 261 analyzed samples, only two beef burgers, one fermented milk “Laban”, one she-camel’s milk, two raw cow’s milk, two cereal baby food, one Maassora cheese and one ready to feed baby milk were contaminated with Cronobacter spp. at a total rate of 3.8%. Accuracy of HiChrome Ent. sakazakii modified agar reach 100% as all of blue-green presumptive colonies were confirmed Cronobacter spp. while other colorless, greenish or with blue center colonies which competed growth with Cronobacter spp. were predominantly Escherichia coli followed by Klebsiella spp. and to less extent Pseudomonas luteola, Citrobacter freundii and Acinetobacter baumanii. Moreover, the isolated strains of Cronobacter were resistant to Amoxicillin, Erythromycin, Vancomycin and Streptomycin, and sensitive to Doxycycline, Enrofloxacin and Gentamycin. Conclusion: This study documents for the first time the occurrence of Cronobacter spp. in beef burger, raw cow’s milk, fermented milk “Laban”, she-camel’s milk, Maassora cheese, cereal baby food and ready to feed baby milk sold in Libya, by using conventional methods, biochemical tests and molecular techniques.