Journal of Applied Microbiology, Vol.106, No.2, 486-495, 2009
Identification of lactic acid bacteria in Moroccan raw milk and traditionally fermented skimmed milk'lben'
To identify lactic acid bacteria (LAB) present in Moroccan dairy products to establish and preserve their microbial species diversity. Thirty-seven samples were collected from different farms. A total of 146 LAB were isolated and subjected to (GTG)(5)-PCR analysis. Comparison of the profiles with data available at the Moroccan Coordinated Collections of Micro-organisms allowed identification of 85 isolates. The remaining 61 were subjected to SDS-PAGE analysis of whole cell proteins. Comparison of the profiles with data available at the Belgian Coordinated Collections of Micro-organisms allowed identification of 43 isolates. Several of the remaining 18 isolates exhibited identical protein electrophoretic fingerprints. Therefore, eight representatives of them were subjected to partial pheS gene sequencing which allowed identification of all remaining isolates. In raw milk, six genera were found while in 'lben', three were found. This is the first report of Leuconostoc kimchii in dairy products. LAB diversity was established using a stepwise polyphasic identification approach. It used the expertise of both research bodies involved in this study and proved to be cost-effective for the identification of all isolates. To establish LAB diversity in Moroccan dairy products which could be a source of strains with specific properties.
Keywords:lactic acid bacteria;Moroccan raw milk;phenylalanyl-tRNA synthase (pheS) gene sequencing;rep-PCR;SDS PAGE;traditional fermented skimmed milk