Evaluation of Antagonstic Effect of Lactic Acid Bacteria Isolated From Ergo Against Selected Foodborne Pathogens Inoculated in to Ayib
| dc.contributor.advisor | Assefa Fassil (PhD) | |
| dc.contributor.advisor | Tesfaye Anteneh (PhD) | |
| dc.contributor.author | Mamo Jermen | |
| dc.date.accessioned | 2018-07-03T06:48:14Z | |
| dc.date.accessioned | 2023-11-08T16:39:45Z | |
| dc.date.available | 2018-07-03T06:48:14Z | |
| dc.date.available | 2023-11-08T16:39:45Z | |
| dc.date.issued | 2011-10 | |
| dc.description.abstract | The antagonistic effects of mixed lactic acid bacteria cultures against foodborne pathogens (Staphylocuccus aureus ATCC 25923, Shigella boydii clinical isolate, Pseudomonas aeruginosa ATCC 25853) were evaluated on pasteurized ayib stored at room temperature. The lactic acid bacteria were tested for acid tolerance at pH 2, 2.5 and 3 for three and six hrs, bile tolerance for 24 and 48 hrs at 0.3% (W/V) bile salt concentration and antimicrobial effect on selected foodborne pathogens by co-culture assay in laboratory medium. Out of the 11 LAB isolates tested for acid tolerance 6 isolates showed survivals at pH 2.5 and pH 3 for 3 hrs and most isolates showed better tolerance to bile salt up on 24 and 48 hrs. Compared to the control (without any LAB bacteria), Ps. aeruginosa were inhibited by all six isolates to varying degree while, Sh. boyidii and S. aureus were inhibited by five of the isolates. Mixed LAB cultures of 106 cfu/g and test pathogens of 103 cfu/g were added together and separately in to ayib collected from Shola market and pasteurized. The effects of LAB against the foodborne pathogens were followed in ayib stored at ambient conditions for 9 days. The antagonistic effect of mixed LAB reduced the pathogens population by more than 2 log units on average on the 6 day. Complete elimination of the test organisms was achieved on day 5, 6, and 7 for Ps. aruginosa, S. aureus and Sh. boyidii respectively. The result indicated the mixed LAB cultures eliminate the test pathogen. Key words: Ayib, Lactic acid bacteria, foodborne pathogens, antimicrobial effect | en_US |
| dc.identifier.uri | http://etd.aau.edu.et/handle/123456789/5641 | |
| dc.language.iso | en | en_US |
| dc.publisher | Addis Ababa University | en_US |
| dc.subject | Ayib | en_US |
| dc.subject | Lactic acid bacteria | en_US |
| dc.subject | foodborne pathogens | en_US |
| dc.subject | antimicrobial effect | en_US |
| dc.title | Evaluation of Antagonstic Effect of Lactic Acid Bacteria Isolated From Ergo Against Selected Foodborne Pathogens Inoculated in to Ayib | en_US |
| dc.type | Thesis | en_US |