Authors : Akharaiyi Fred Coolborn
Abstract: Indicator bacteria of pathogenic and food spoilage capabilities were isolated from food sources, water and human feaces using MacConkey agar, Deoxycholate citrate agar and selenite F medium. Lactic Acid Bacteria (LAB) were isolated from soil, wine local cheese and corn slurry using MRS medium. Well-in-agar and paper disc methods were emplored for the antagonistic assay. The sensitivity of the indicator bacteria to LAB was indicated by clear zones of inhibition. Lactobacillus acidophilus exhibited the greatest inhibitory effect while Lactobacillus jugurti and Lactobacillus casei could not demonstrate visible inhibitory affinity on all the indicator bacteria. However, the LAB antagonistic activity over the indicator bacteria, displayed more elaborate inhibitory zones in the well -in-agar (5-6 mm) than the paper disc method (3-20 mm). Also the human enteropathogen assay with well-in-agar was between (2-26 mm) over (1- 8 mm) with the paper disc method.
Akharaiyi Fred Coolborn , 2005. Antibacterial Quantification from Lactic Acid Bacteria Isolated from Food Sources and Soil . Journal of Food Technology, 3: 568-571.