Modulation of jade perch microbiota using encapsulated, host-derived microbial compositions

The exacerbation of infection-related losses due to global warming and aquaculture intensification have necessitated effective mitigation strategies. Among these strategies, host-derived probiotics as a bio-remediation agent are promising to enhance fish disease resistance by competitively occupying...

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Main Author: Li, Wenrui
Other Authors: Loo Say Chye, Joachim
Format: Thesis-Doctor of Philosophy
Language:English
Published: Nanyang Technological University 2024
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Online Access:https://hdl.handle.net/10356/173982
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spelling sg-ntu-dr.10356-1739822024-04-09T03:58:58Z Modulation of jade perch microbiota using encapsulated, host-derived microbial compositions Li, Wenrui Loo Say Chye, Joachim Interdisciplinary Graduate School (IGS) NTU Institute for Health Technologies JoachimLoo@ntu.edu.sg Engineering Medicine, Health and Life Sciences Aquaculture Probiotics Enterococcus hirae Jade perch Gut microbiota The exacerbation of infection-related losses due to global warming and aquaculture intensification have necessitated effective mitigation strategies. Among these strategies, host-derived probiotics as a bio-remediation agent are promising to enhance fish disease resistance by competitively occupying adhesion sites, providing nutritional benefits, and producing antimicrobial substances that combat pathogens in the native environments of the probiotics. This research started by screening bacteria from the gut microbiota of Singapore’s newly farmed freshwater jade perch (Scortum barcoo). These isolates were evaluated for their efficacy against various freshwater pathogens, and their safety profiles were also thoroughly assessed to ensure their suitability for practical implementation. Considering the viability of probiotics in fish feed during storage and feeding is unreliable without encapsulation, selecting appropriate encapsulants becomes crucial for maintaining probiotic activity. Despite the importance of probiotic encapsulation, to the best of our knowledge, no reports have investigated the interactions between common encapsulants and the gut microbiota of aquacultured fish. This aspect has yet to be adequately addressed. This research looked into the metabolic interactions of widely used polysaccharide encapsulants with the gut microbiota of fish, focusing on evaluating the production of short chain fatty acids (SCFAs) and the effects on the composition of the gut microflora. The encapsulants with metabolic functionality were subsequently employed to encapsulate the probiotics, examining two encapsulation methods: needle extrusion and spray drying. The probiotics were effectively protected within the simulated gastric fluid (SGF) in both cases. At the same time, the spray drying method proved to be more successful in ensuring adequate release of the probiotics within the simulated intestinal fluid (SIF). This research demonstrated the framework for making informed decisions on the combination of probiotics and encapsulants tailored to specific fish species. This approach is anticipated to improve feed efficiency and overall productivity significantly. Further in vivo feeding trials will be required to assess the practical applicability of encapsulated probiotics in aquaculture. Doctor of Philosophy 2024-03-11T07:32:46Z 2024-03-11T07:32:46Z 2023 Thesis-Doctor of Philosophy Li, W. (2023). Modulation of jade perch microbiota using encapsulated, host-derived microbial compositions. Doctoral thesis, Nanyang Technological University, Singapore. https://hdl.handle.net/10356/173982 https://hdl.handle.net/10356/173982 10.32657/10356/173982 en SFS_RND_SUFP_001_06 SNBC/2021/SF2/P04 RG79/22 RT03/21 This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License (CC BY-NC 4.0). application/pdf Nanyang Technological University
institution Nanyang Technological University
building NTU Library
continent Asia
country Singapore
Singapore
content_provider NTU Library
collection DR-NTU
language English
topic Engineering
Medicine, Health and Life Sciences
Aquaculture
Probiotics
Enterococcus hirae
Jade perch
Gut microbiota
spellingShingle Engineering
Medicine, Health and Life Sciences
Aquaculture
Probiotics
Enterococcus hirae
Jade perch
Gut microbiota
Li, Wenrui
Modulation of jade perch microbiota using encapsulated, host-derived microbial compositions
description The exacerbation of infection-related losses due to global warming and aquaculture intensification have necessitated effective mitigation strategies. Among these strategies, host-derived probiotics as a bio-remediation agent are promising to enhance fish disease resistance by competitively occupying adhesion sites, providing nutritional benefits, and producing antimicrobial substances that combat pathogens in the native environments of the probiotics. This research started by screening bacteria from the gut microbiota of Singapore’s newly farmed freshwater jade perch (Scortum barcoo). These isolates were evaluated for their efficacy against various freshwater pathogens, and their safety profiles were also thoroughly assessed to ensure their suitability for practical implementation. Considering the viability of probiotics in fish feed during storage and feeding is unreliable without encapsulation, selecting appropriate encapsulants becomes crucial for maintaining probiotic activity. Despite the importance of probiotic encapsulation, to the best of our knowledge, no reports have investigated the interactions between common encapsulants and the gut microbiota of aquacultured fish. This aspect has yet to be adequately addressed. This research looked into the metabolic interactions of widely used polysaccharide encapsulants with the gut microbiota of fish, focusing on evaluating the production of short chain fatty acids (SCFAs) and the effects on the composition of the gut microflora. The encapsulants with metabolic functionality were subsequently employed to encapsulate the probiotics, examining two encapsulation methods: needle extrusion and spray drying. The probiotics were effectively protected within the simulated gastric fluid (SGF) in both cases. At the same time, the spray drying method proved to be more successful in ensuring adequate release of the probiotics within the simulated intestinal fluid (SIF). This research demonstrated the framework for making informed decisions on the combination of probiotics and encapsulants tailored to specific fish species. This approach is anticipated to improve feed efficiency and overall productivity significantly. Further in vivo feeding trials will be required to assess the practical applicability of encapsulated probiotics in aquaculture.
author2 Loo Say Chye, Joachim
author_facet Loo Say Chye, Joachim
Li, Wenrui
format Thesis-Doctor of Philosophy
author Li, Wenrui
author_sort Li, Wenrui
title Modulation of jade perch microbiota using encapsulated, host-derived microbial compositions
title_short Modulation of jade perch microbiota using encapsulated, host-derived microbial compositions
title_full Modulation of jade perch microbiota using encapsulated, host-derived microbial compositions
title_fullStr Modulation of jade perch microbiota using encapsulated, host-derived microbial compositions
title_full_unstemmed Modulation of jade perch microbiota using encapsulated, host-derived microbial compositions
title_sort modulation of jade perch microbiota using encapsulated, host-derived microbial compositions
publisher Nanyang Technological University
publishDate 2024
url https://hdl.handle.net/10356/173982
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