Use of metabolites of therapeutic Lactic acid bacteria to inhibit four species veterinary pathogenic bacteria Ali H. A . Hamid , S.C. Abood , H.R.Al sharefe

Abstract

This study aimed to detect metabolites inhibition activity for three therapeutic
Lactic acid bacteria Lactobacillus acidophilus (Lb. acid.) , Lactobacillus reuteri
(Lb. reut.) and Bifidobacterium ssp. (Bif.) which were grown in whole milk and
Man Reqosa and Sharp (MRS) broth as single or double (Lb. acid. + Bif.) or
mixed (Lb. reut + Bif. + Lb. acid) culture Cell Free Extract (CFE) of these
culture which contained their metabolites of Lactic acid bacteria (exclusion Lb.
reut.) showed good inhibition against four species of pathogenic Escherichia
coli ; Salmonella typhimurium ; Proteus volgaris and Staphylococcus aureus.
inhibition activity against E. coli culture showed that 72 hours was the best
incubation time for Lactic acid bacteria to produce more metabolite with best
inhibition activity. Metabolite (CFE) of Lb. Acid culture grown in milk and
MRS broth showed the best inhibition activity against all of Gram Positive and
Gram negative test bacteria with over all inhibition zone diameter was 14.6 and
15.3 mm for milk and MRS broth supernatant respectively and this activity
remained for more than one week as inhibition zone diameter were 13.4 and
14.5 mm for supernatant of milk and MRS respectively.