PHENOTYPIC AND GENOTYPIC IDENTIFICATION OF BACTERIOCIN PRODUCER LACTIC ACID BACTERIA ISOLATED FROM COWS MILK
2016
Hibbat Al Rahman Ryad | Fawziah A. Abdullah
The Phenotypic identification results revealed that Lactic Acid Bacteria (LAB)isolates which is characterized by both Gram positive and catalase negative reactionswas observed in 51 % of cow raw milk bacterial isolates with 51% an overall ratio.Thehigher results(58.5%.) of conventionallbacteriological analysis were observed in rawmilk bacterial isolates of cows lat first age group(≥3 - < 9 year) , There wassignificantleffect ( p< 0.05)for the cows age on the raw milk bacterialisolatesldistribution .The number of parturition affect significantly ( p< 0.05) on thelrawmilk bacterial isolates distribution and high ratio( 52%)of LAB isolateslwas observed incows with ≥6-<12 number oflparturitionDepending on genotypic identification results the high ratio (100%) ofpositivelresults of 16S rDNA based PCR appeared in all of raw milk bacterial isolatesof cowslat second age group(≥9 - ˂15 year) , and the difference between the twoagelgroups stastically was not considered significant (P>0.05)..The number ofparturitionlhad اhigh significant effect (p< 0.001) on16S rDNA based PCRpositivelresults and high ratio(50%) of these results was observed inlcows with 1 - <6 number oflparturition.Subsequent bacteriocin encoding geneslbased PCR analysisof 16S rDNA genes based PCR positive LAB revealed that higher ratio of PCRpositive results (60.9%) was observed in EntlB followed by Nis encodinggenes(30.4%) . High significant difference(P<0.01) was observed amonglthe Nis, EntA and Ent B encoding genes based PCR positivelresults.
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