Table 3.
In vitro, animal, and human studies evaluating the effect of no-sulfated algal polysaccharides (alginate and laminaran) on the gut microbiota and health.
| Algal polysaccharides | Model | Changes in bacterial populations | SCFA production | Putrefactive metabolites | Health effects | References |
|---|---|---|---|---|---|---|
| Alginate, alginate-OS, poly-mannuronic acid |
In vitro: - Pure cultures - Bioreactor with human GM |
↗Bacteroides
↗Bifidobacterium ↗Lactobacillus |
↗ SCFAs including butyrate | ↘phenol, indole, NH3 | Not applicable | (55–58, 60, 61, 64, 65) |
|
Animal - Rats with normal diet - Mice with HFD - Rats fed HPD |
↗Butyrate-producing bacteria ↗Bifidobacterium ↗Lactobacillus ↗Bacteroides ↗A. muciniphila ↘Enterobacteriaceae |
↗SCFAs | ↘phenol, indole, NH3, H2S | Normalization of metabolic and inflammatory parameters in animals fed HFD | (59, 61–64, 66) | |
| Human | ↗Bifidobacterium | ↗ Acetate, Propionate | ↘H2S, phenol, p-cresol, indole, skatole, NH3 | Not reported | (67) | |
| Laminaran |
In vitro: - Pure cultures - Bioreactor with human GM |
↗Bacteroides ↗Lactobacillus |
↗ SCFAs mainly butyrate and propionate, | ↘H2S, phenol, p-cresol, indole, skatole, NH3 | Not applicable - | (55, 64, 65, 68–70) |
|
Animal - Rats fed ND - Rats fed a HPD or HFD - Post weaned piglets |
↗ Bacteroides ↗Coprobacillus ↗P. distasonis ↗Prevotella ↘Enterobacteriaceae ↗GH, PL and GT expressing bacteria |
↗SCFAs mainly butyrate, propionate, and lactate | ↘H2S, phenol, indole | ↗colonic expression of neutral mucins ↗ileal expression of glucose transporters ↘Inflammation markers |
(59, 64–66, 71–74) |
GM, gut microbiota; H2S, hydrogen sulfide; HFD, high fat diet; HPD, high protein diet; ND, normal diet; GH, glycoside hydrolase; PL, polysaccharide lyase; GT, glycosyl transferase; SCFA, short chain fatty acids.