Effect of interspecies quorum quenching on horizontal transfer of antibiotic resistant genes and evaluation of antagonistic activity of probiotics | |
| Author | Modisa |
| Call Number | AIT Thesis no.FB-21-08 |
| Subject(s) | Antibiotic resistance Probiotics Quorum sensing (Microbiology) |
| Note | A thesis submitted in partial fulfillment of the requirements for the degree of Master of Science in Food Engineering and Bioprocess Technology, School of Environment, Resources and Development |
| Publisher | Asian Institute of Technology |
| Series Statement | Thesis ; no.FB-21-08 |
| Abstract | In terms of animal numbers, poultry remains the world's most extensive domestic animal stock. On both a commercial and a traditional family level, the sector has grown dramatically in several countries. The poultry business directly employs over three million people and produces most of the meat and eggs consumed. Significant public health concerns have been expressed because most record potential pathogenic bacteria to other poultry dangers. Many studies showed that pathogens affecting poultry animals are Proteus Mirabilis and K. pneumoniae . And some of their strains are multi drug resistant. In this study, among 30 samples of K. pneumoniae & P. mirabilis some MDR are found. Further, Gentamycin (93.3%), chloramphenicol (93.3%) and then Kanamycin (86%) have lethal effects on K. pneumoniae . While 20% (3) samples found MDR. And K. pneumoniae showed resistance against, Ampicillin and Ciprofloxacin. P. mirabilis was sensitive to chloramphenicol (92%), and Gentamycin (71%). While resistant against Ciprofloxacin (100%), 91% against Streptomycin & Ampicillin. 50% MDR was recorded. The study employed the isolated and identified antibiotic resistant pathogens to find the role of the communication between bacteria through signaling molecules called autoinducers. This communication facilitates the biofilm formation which acts as blanket to protect the bacteria against external environment and horizontal gene transfer. The study opted to stop the quorum sensing called as quorum quenching by using synthetic chemical which was previously proven to have inhibiting effects against communication system of bacteria. The results showed visible reduction in the biofilm formation of the interspecies co-culture while the results for horizontal gene transfer did not provide clear evidence in regard to the role of quorum sensing in horizontal gene transfer. Furthermore, a probiotic, L. casei was tested to find its antagonistic activity against the isolated pathogenic bacteria. Where it showed 2-3 Log reduction in the initial CFU/ml of each pathogen. While the probiotic showed visible aggregation with K. pneumoniae , but no aggregation was seen to occur between L. casei and P. mirabilis. It was observed through the agar over-lay assay, that the L. casei probiotic produced certain compounds which have the capability to target and kill the two pathogens under study. |
| Year | 2021 |
| Corresponding Series Added Entry | Asian Institute of Technology. Thesis ; no.FB-21-08 |
| Type | Thesis |
| School | School of Environment, Resources, and Development (SERD) |
| Department | Department of Food, Agriculture and Natural Resources (Former title: Department of Food Agriculture, and BioResources (DFAB)) |
| Academic Program/FoS | Food Engineering and Bioprocess Technology (FB) |
| Chairperson(s) | Anal, Anil Kumar; |
| Examination Committee(s) | Loc Thai Nguyen;Datta, Avishek; |
| Scholarship Donor(s) | Her Majesty the Queen’s Scholarships (Thailand); |
| Degree | Thesis (M. Sc.) - Asian Institute of Technology, 2021 |