A Study of the Effect of Some Growth Conditions on Inhibitory Activity of Lactobacillus delbrueckii and Lactobacillus   fermentum to reduce Growth of E.coli

Sabah Rezouqi, Nada; Ramadhan, Avven; Nasir, Bashair; Abd-alatif Hasin, Widian

	A Study of the Effect of Some Growth Conditions on Inhibitory Activity of Lactobacillus delbrueckii and Lactobacillus fermentum to reduce Growth of E.coli
Iraqi Journal of Science
Article 1, Volume 57, Issue 2, 2016, Pages 1357-1364
Authors
Nada Sabah Rezouqi; Avven Ramadhan; Bashair Nasir; Widian Abd-alatif Hasin
Abstract
Aimed this study to testing some of growth conditions on inhibitory activity of Lactobacillus delbrueckii bacteria and L.fermentum at various concentrations (50, 70, 90, 100) % on the growth of E.coli isolate used in this study. The results showed that the bacteria L. delbrueckii and L.fermentum at 100% concentrations gave highest inhibitory activity against E.coli with inhibition zone 27mm , while inhibition zone reached 17 mm at 50% concentration and when using a bacterial filtrate of L. delbrueckii and L.fermentum at 100% concentrations inhibition zone was with diameter 23mm , also stability of bactiriocin was examined against pH values, the results showed that highest stability in acidic PH compared to alkaline PH. The treatment of bacteriocins with salts suchas NaCl and KCl revealed low effect in inhibition zone with 1 & 5% concetrations. However the higher concentration of salt 5% caused high reduction and caused to loss of inhibitory activity of bacteriocins compared to1% with inhibition zone diameter were 16 and 18 mm for Nacl and Kcl at 1% while it decreased to 14 and 15 mm at % 5 . The results showed that stability of bacteriocins at temperature 37 ºC than 25 ºC

Statistics Article View: 167 PDF Download: 62