Quorum sensing control for microbial management of the aquaculture food chain rotifer-turbot
In this PhD study, we investigated the host-microbe interactions in a “rotifer-turbot larvae” food chain, and the isolation and application of N-acyl homoserine lactone (AHL)-degrading bacteria as a strategy for microbial control in turbot larviculture. In Chapter 2, we give a summary of the studies...
| Main Author: | |
|---|---|
| Other Authors: | , |
| Format: | Doctoral or Postdoctoral Thesis |
| Language: | English |
| Published: |
Ghent University. Faculty of Bioscience Engineering
2007
|
| Subjects: | |
| Online Access: | https://biblio.ugent.be/publication/468778 http://hdl.handle.net/1854/LU-468778 https://biblio.ugent.be/publication/468778/file/1879758 |
| Summary: | In this PhD study, we investigated the host-microbe interactions in a “rotifer-turbot larvae” food chain, and the isolation and application of N-acyl homoserine lactone (AHL)-degrading bacteria as a strategy for microbial control in turbot larviculture. In Chapter 2, we give a summary of the studies on probiotics which have been done in fish and shellfish larviculture, with a critical overview of the way of verifying the mechanisms of action in vivo. Several approaches are suggested for further in vivo research, including the study on the dynamics of the gut microbiota, the use of gnotobiotic animals as model system, and the application of molecular technology to study the host-microbe and microbe-microbe interactions. In Chapter 3, we developed a technique to obtain bacteria-free rotifers (Brachionus plicatilis sensu stricto, clone 10), by hatching amictic eggs treated with 0.005-0.01 % glutaraldehyde solution for 1-2 h at 28°C. The gnotobiotically grown Brachionus were used as a model to test the effect of microbial communities (MCs) which were isolated from normal-performing or from crashed rotifer cultures. These MCs were either used freshly or preserved at -80°C and regrown on Marine Agar. Different MCs were introduced into gnotobiotic Brachionus cultures in combination with three different food types, i.e. Chlorella, wild-type baker’s yeast and the derived mnn9 yeast mutant, which is deficient in the cell wall-bound mannoprotein. In the absence of MCs or when the autoclave-killed MCs were added, Chlorella was always the best food, while lower growth rates were observed with the wild-type yeast and the mnn9 yeast mutant. In the presence of live MCs and when Brachionus were fed with Chlorella, the added MCs had no effect on Brachionus performance. In contrast, when yeast strains were used as major food, all the tested MCs were able to increase the Brachionus growth rate. In addition, the experiments with autoclave-killed MCs yielded no increase in Brachionus growth rate compared to the control treatment, ... |
|---|