Screening and identification of thermostable probiotics for chicken feed | |
| Author | Lalida Saeeah |
| Call Number | AIT Thesis no.FB-08-13 |
| Subject(s) | Probiotics Chicken feed industry--Thailand |
| 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-08-13 |
| Abstract | One hundred and four strains of lactic acid bacteria (LAB) were isolated from different chicken farms in Thailand including a research farm, a commercial farm and a fighting cock farm. From the seven samples collected only forty stable isolates could survive storage and sub-culturing. These isolates were checked for morphological characteristics and cultured in MRS broth containing 5%NaCl. After that the surviving isolated were cultured in temperature conditions of 45, 50, 55 and 60°C. Twenty-four isolates were able to survive and were selected for the further studies. The selected isolates were identified into genus and species level. Specific characteristics such as catalase production, lactic acid production, proteolytic activity and carbohydrate utilization were used to identify the genus of the selected isolates. It was found that these isolates consisted of 41.7% Enterococcus spp., 37.5% Pidiococcus spp., 12.5% Lactobacillus spp., and 8.3% were Leuconoctoc spp. and Oenococcus spp .. Ten strains which had proteolytic activity were selected for identification by API identification kit. They consisted of Pediococcus pentosaceus 1, Pediococcus acidilactici and Lactobacillus brevis 1 species. The strains which had the highest percentage of identification characteristics in the API analysis were selected for characterization. Three selected strains were further studied for thermostable probiotic characteristics such as heat tolerance, acid tolerance, bile salt tolerance, adhesion and antibacterial activity. In the heat tolerance study, Pediococcus pentosaceus 1 showed the ability to grow well at 60 and 70°C whereas Lactobacillus brevis 1 showed the ability to grow at high temperature for short time. Pediococcus acidilactici showed the best ability to grow in high acidity condition. However, Pediococcus acidilactici showed the best ability to grow in bile salt condition. Lactobacillus brevis 1 showed the highest ability of adhesiveness. All three strains showed the same ability of antibacterial activity. Overall, in the probiotic characterization tests of acid and bile salt tolerance, adherence and antimicrobial activity all three screened microorganisms seem to perform equally well. Pediococcus acidilactici seems to be better than the other two strains in bile tolerance significantly. The best strains screened are mainly from the fighting cock chicken farm. This indicates that the flora present in the chicken grown for strength required in the fights and grown on indigenous feed mixtures have a better natural society and and a good source of probiotics. In actual application for the use of these strains in chicken feed production it may be preferred to check viability in an actual extrusion feed production process and also its actual efficacy by feeding chickens |
| Year | 2008 |
| Corresponding Series Added Entry | Asian Institute of Technology. Thesis ; no. FB-08-13 |
| 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) | Rakshit, Sudip Kumar; |
| Examination Committee(s) | Athapol Noomhorm;Ranamukhaarachchi, S.L.; |
| Scholarship Donor(s) | RTG Fellowship; |
| Degree | Thesis (M.Sc.) - Asian Institute of Technology, 2008 |