The Effect Allium sativum (Garlic Extract) as Prebiotic Substance on the Activity of Probiotic Bacteria Lactobacillus acidophilus Against Some Locally Isolates of Pathogenic Bacteria

The aim of this study was to improve the growth and inhibitory activity of the selected Lactobacillus isolate.A total of twenty samples of dairy products (fresh yogurt) were collected. Seven isolates of Lactobacillusspecies . were obtained, and identified as three Lactobacillus fermentum, three Lactobacillus acidophilus andone of Lactobacillus brevis. The growth of lactobacillus acidophilus was counted , also inhibitory activity ofLactobacillus acidophilus against some pathogenic bacteria was tested) for two different incubation periodsbefore the addition of Allium sativum(garlic extract) as prebiotic substances. three different concentrationsof it were used by addition of it toDe Man, Rogosa and Sharpe agar (MRS) medium as prebiotic substances , and two incubation periods(24, 48) hour. The effect of Allium sativum on the growth of probiotic bacteria was evaluated, measurementof Lactobacillus acidophilus growth curve was done after and before adding garlic extract. For analyzinginhibitory activity of Lactobacillus acidophilus with the Allium ,results showed that Lactobacillus acidophiluspropagated in MRS fortified with 20% and 30% v/v garlic extract with incubation period 24 hr by giving thehighest inhibition zone.It was concluded that Lactobacillus.acidophilus isolate can grow well and exhibit good effect against Gramnegative bacteria in a medium containing garlic extract (that is added as a substrate supporting probioticgrowth and activity). also it was clear that filtrate of Lactobacillus .acidophilus isolate that propagatingin spesific broth fortified with 20% garlic extract at 48 hr incubation period produce antibacterial effectbetter than 10% , it was concluded that prebiotic treatment enhance the growth of Lactobacillus acidophilusespecially at 24 hr. this may due to fructooligosaccharide content in garlic , also when propagated in MRSwithout prebiotic treatment, and which may due to highly decrease in pH which cause inhibition the growthof Lactobacillus acidophillus.