Cronobacter Support
05-06-2009, 09:56 AM
1st International Conference on Cronobacter Poster Abstract 17
Evaluation of a new onestep enrichment for the isolation of Cronobacter spp. from powdered milk formula in association with a chromogenic medium.
The aim of the present study was to evaluate a new one-step enrichment protocol for the isolation of Cronobacter spp. (Enterobacter sakazakii) from powdered infant formula. This protocol consists of a combined pre-enrichment/enrichment broth (Cronobacter Enrichment Broth, bioMérieux Marcy l’Etoile, France) used in conjunction with selective-differential agar ChromID Sakazakii (bioMérieux Marcy l’Etoile, France) to facilitate a shortened two-day cultural method for detection of Cronobacter. The Cronobacter Enrichment Broth (CEB) was evaluated using powdered infant formula (PIF) spiked with low concentrations of 10 lyophilized strains, representative of the genus Cronobacter. The isolation of strains was compared in parallel with the current ISO/TS 22964 and a recently proposed differential screening broth method for the detection of Cronobacter. All of the Cronobacter strains were recovered using the CEB whereas one strain was not detected using either the current ISO/TS 22964 or the differential screening broth method. Counts of the cell concentration after enrichment showed a significantly higher bacterial concentration in the CEB than in the other enrichment broths. There was no difference in the cell concentration for cultures grown in CEB at 37 and 41.5°C. Cronobacter was recovered from both 1/10 (50 g:450 ml) and 1/5.5 (100 g:450 ml) “sample to broth” ratios. No significant difference was observed between the cell counts obtained from either ratio. This study found CEB to be significantly better at recovering Cronobacter spp. from PIF than the other enrichment media tested. Overall, the use of CEB with a differential plating media such as ChromID Sakazakii facilitates the rapid release (40-48 h) of PIF.
Stephen O’Brien1, Orla Condell1, Brendan Healy1, Antoine Vimont2, David Mosticone2, Pascal Montes2, Séamus Fanning1 and Carol Iversen1
1 Centres for Food Safety & Food-borne Zoonomics, Veterinary Sciences Centre, School of Agriculture, University College Dublin, Belfield, Dublin 4, Ireland. 2 bioMérieux Industry F-69280 Marcy l'Étoile, France.
Evaluation of a new onestep enrichment for the isolation of Cronobacter spp. from powdered milk formula in association with a chromogenic medium.
The aim of the present study was to evaluate a new one-step enrichment protocol for the isolation of Cronobacter spp. (Enterobacter sakazakii) from powdered infant formula. This protocol consists of a combined pre-enrichment/enrichment broth (Cronobacter Enrichment Broth, bioMérieux Marcy l’Etoile, France) used in conjunction with selective-differential agar ChromID Sakazakii (bioMérieux Marcy l’Etoile, France) to facilitate a shortened two-day cultural method for detection of Cronobacter. The Cronobacter Enrichment Broth (CEB) was evaluated using powdered infant formula (PIF) spiked with low concentrations of 10 lyophilized strains, representative of the genus Cronobacter. The isolation of strains was compared in parallel with the current ISO/TS 22964 and a recently proposed differential screening broth method for the detection of Cronobacter. All of the Cronobacter strains were recovered using the CEB whereas one strain was not detected using either the current ISO/TS 22964 or the differential screening broth method. Counts of the cell concentration after enrichment showed a significantly higher bacterial concentration in the CEB than in the other enrichment broths. There was no difference in the cell concentration for cultures grown in CEB at 37 and 41.5°C. Cronobacter was recovered from both 1/10 (50 g:450 ml) and 1/5.5 (100 g:450 ml) “sample to broth” ratios. No significant difference was observed between the cell counts obtained from either ratio. This study found CEB to be significantly better at recovering Cronobacter spp. from PIF than the other enrichment media tested. Overall, the use of CEB with a differential plating media such as ChromID Sakazakii facilitates the rapid release (40-48 h) of PIF.
Stephen O’Brien1, Orla Condell1, Brendan Healy1, Antoine Vimont2, David Mosticone2, Pascal Montes2, Séamus Fanning1 and Carol Iversen1
1 Centres for Food Safety & Food-borne Zoonomics, Veterinary Sciences Centre, School of Agriculture, University College Dublin, Belfield, Dublin 4, Ireland. 2 bioMérieux Industry F-69280 Marcy l'Étoile, France.