الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
Antimicrobial compounds produced by some bifidobacterium
strains (Bifidobacterium bifidum and Bifidobacterium lactis Bb-12) were
tested as antimicrobial activity towards gram-negative pathogenic
bacteria. Agar diffusion method and minimum inhibitory concentration
were performed. Bifidobacteria were found to exert strong inhibitory
activity towards gram-negative indicator bacteria, namely Aeromonas
hydrophilia, Aeromonas caviae, Aeromonas sobria, Pseudomonas
flouresent, Pseudomonas aeruginosa, Pseudomonas fragi and Escherichia
coli 0157:H7. The data showed that Aeromonas caviae and Aeromonas
sobria were more sensitive to bacteriocins than Aeromonas hydrophilia,
also Aeromonas spp. were more resistance to bacteriocins than
Pseudomonas spp. and E. coli 0157:H7. This antimicrobial substance
remained active after storage at 3 and -18°C for 3 months, was stable at
pH values of 5 to 7 and resistant to heat and showed a bactericidal action.
Addition of bifidin or bifilact Bb-12 to ground beef (Pattie) resulted in
reduction of E. coli count by ratio 100% in sample containing 8% fat
when grilled to an internal temperature of 68°C. The results of this study
will be beneficial to the food industry in designing HACCP plans to
effectively eliminate gram-negative pathogenic bacteria especially E. coli
0157:H7 in meat product. Extension of shelf life the refrigerated stuffed
chicken might be further improved by using appropriate concentrations of
bifid in or bifilact Bb-12.