Etude du Pouvoir inhibiteur des bactéries lactiques autochtones à partir de blé fermenté vis-à-vis d’une souche lactique Pediococcus acidilactici et de souches pathogènes de référence

Abstract

Lactic acid bacteria are used in the fermentation and bioconservation of foods through the production of organic acids and other antibacterial. The purpose of this characteristic physioloical and biochimical study and the search for lactic acid bacteria producing antimicrobial substances in nineteen lactic isolates that have already been isolated from fermented « Hamoum »wheat from the Mazouna region. The study of the morphological caracters showed two forms,bacilli and shell to proportions(21,05% of the bacilli and 78,94% of the shells).The physiological and biochemical study of the isolates revealed hat they belong to five genea :Lactobacillus (21,05%),Pediococcus(5,26%), Enterococcus(52,63%), Lactococcus(10,52%),Streptococcus(10,52%).The study of the antagonistic power of nineteen isolated strains of fermented wheat against four Gram-positive pathogenic strains (Escherichia coli ATCC 25122,Staphylococcus aureus ATCC 33862 ,Bacillus cereus ATCC 10876,Pseudomonas aeroginosa ATCC 27853 ),and a lactic acid bacterium of the genusPediococcus acidilactici. Have allowedresults (97 ,36% presence of inhibition and 2,63% inhibition absences). The use of a buffered medium detected the acidity inhibitions at the rate of 5.26%, and those due to the production of other agents was 94.73%.