Laminarin as a Personalized, Bioaccessible Prebiotic: Shaping the Gut Microbiome and Enhancing the Production of Beneficial Metabolites
Laminarin is a nondigestible polysaccharide accessible to gut microbiota. This study investigates the impact of laminarin on the gut microbiome using an in vitro fecal incubation model and metabolome analysis. Fecal samples were collected from 19 healthy donors and incubated with or without laminarin for 24 hours. To minimize inter-individual variability, enterotyping was applied to the baseline fecal microbiota, categorizing 13 subjects with a Bacteroides-dominant type (enterotype B) and 6 subjects with a Prevotella-dominant type (enterotype P). Alpha diversity was significantly reduced in the laminarin-treated group compared to the untreated control group in both enterotype B and P. However, significant structural changes in microbial communities were observed, as indicated by weighted UniFrac distance in both enterotypes. Notably, short-chain fatty acid (SCFA)-producing bacteria, such as Roseburia, Faecalibacterium, and Fusicatenibacter, were overrepresented in response to laminarin exclusively in enterotype B. Furthermore, significant enrichments of ?-aminobutyric acid (GABA) producers, such as Bacteroides and Parabacteroides, were observed following laminarin treatment in enterotype B. Consistent with the enriched taxa, levels of butyrate and GABA were significantly increased in the laminarin-treated group compared to the control in enterotype B. Additionally, levels of indolelactate (ILA) were also significantly elevated in response to laminarin. In vitro gastrointestinal model systems demonstrated the nondigestibility of laminarin. Furthermore, in vitro growth assays showed that laminarin promoted the proliferation of Bacteroides species by facilitating its decomposition and utilization as a sole carbon source. These findings suggest the potential of laminarin as a prebiotic, as it induces changes in microbial structure, enhances the production of beneficial metabolites, including SCFAs and GABA, supports the growth of probiotics, and demonstrates bioaccessibility to gut microbiota.
Laminarin is a nondigestible polysaccharide accessible to gut microbiota. This study investigates the impact of laminarin on the gut microbiome using an in vitro fecal incubation model and metabolome analysis. Fecal samples were collected from 19 healthy donors and incubated with or without laminarin for 24 hours. To minimize inter-individual variability, enterotyping was applied to the baseline fecal microbiota, categorizing 13 subjects with a Bacteroides-dominant type (enterotype B) and 6 subjects with a Prevotella-dominant type (enterotype P). Alpha diversity was significantly reduced in the laminarin-treated group compared to the untreated control group in both enterotype B and P. However, significant structural changes in microbial communities were observed, as indicated by weighted UniFrac distance in both enterotypes. Notably, short-chain fatty acid (SCFA)-producing bacteria, such as Roseburia, Faecalibacterium, and Fusicatenibacter, were overrepresented in response to laminarin exclusively in enterotype B. Furthermore, significant enrichments of ?-aminobutyric acid (GABA) producers, such as Bacteroides and Parabacteroides, were observed following laminarin treatment in enterotype B. Consistent with the enriched taxa, levels of butyrate and GABA were significantly increased in the laminarin-treated group compared to the control in enterotype B. Additionally, levels of indolelactate (ILA) were also significantly elevated in response to laminarin. In vitro gastrointestinal model systems demonstrated the nondigestibility of laminarin. Furthermore, in vitro growth assays showed that laminarin promoted the proliferation of Bacteroides species by facilitating its decomposition and utilization as a sole carbon source. These findings suggest the potential of laminarin as a prebiotic, as it induces changes in microbial structure, enhances the production of beneficial metabolites, including SCFAs and GABA, supports the growth of probiotics, and demonstrates bioaccessibility to gut microbiota.
University of California San Diego Microbiome Initiative