The present study aims at isolation and characterization of Lactobacillus species from Makdoos a locally stuffed and fermented vegetables and to characterize some selected isolates for their probiotic potential. Sixteen isolated Lactobacillus strains (7 Lactobacillus plantarum 1, 3 Lactobacillus pentosus, 1 Lactobacillus brevis 1, 1 Lactobacillus brevis 3, 1 Lactobacillus rhamnosus,1 Lactobacillus salivarius and two were not fully assigned to a species were chosen for further testing. These were tested for their probiotic potential. This included survival at low pH and in gastrointestinal simulated juice, antagonistic activity against Salmonella typhimurium, Escherichia coli, Bacillus cereus and a methicillin-resistant Staphylococcus aureus (MRSA) isolate, bile tolerance, antibiotic resistance to 8 antibiotics and adhesion to Caco-2 cells. Most isolates, especially Lactobacillus plantarum 1, were tolerant to acidity and intestinal conditions after exposure for three and four hours respectively with reduction less than one log cycle of the starting CFU/ml. The same trend was observed in respect to bile tolerance with slight variations. All isolates inhibited the growth of the tested pathogens and were highly effective against Bacillus cereus, Salmonella typhimurium and MRSA isolate. As for antibiotic resistance, it was pronounced against tetracycline, streptomycin kanamycin, and trimethoprim. Some isolates, M5 and and M6 showed resistance to 6 or more of the 8 antibiotics tested and others were resistant to 3 or 4 antibiotics. As for adhesion ability to Caco-2 cells, some isolates showed superior ability i.e more than 80% relative adhesion compared with Escherichia coli and higher than the probiotic strain Lactobacillus reuteri DSMZ 20056. In Conclusion, the ability of these isolates to survive well under the tested conditions as well as being non-hemolytic renders them as good probiotic candidates for health and food technology benefits. Results also prove that the traditionally fermented vegetables are good sources for probiotic Lactobacillus. However, further in vivo studies are needed to substantiate their potential use in different applications.
 

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