Table 2.
BPs with therapeutic potential against T2DM.
| Bioactive Polysaccharides | Monosaccharide Composition and Molecular Weight (Mw) | Dosage | Study Approaches | Major Findings | Mode of Action–Gut Microbiota | References |
|---|---|---|---|---|---|---|
| Acidic tea polysaccharides | Mw: 3.9285 × 104 Da | 200, 400, and 800 mg/kg | High-fat diet-streptozotocin-induced rat models | Improved plasma and liver lipid metabolism | Increased Bifidobacterium, Blautia, Dorea, and Oscillospira, and reduction in Desulfovibrio and Lactobacillus; Improved secondary BA biosynthesis and primary BA biosynthesis | [230] |
| White hyacinth bean polysaccharides | Composed of glucose, rhamnose, galactonic acid, galactose, xylose, and arabinose in the molar ratio of 23.23:6.2:5.09:2.76:2.4:0.48; Mw: 2.3 × 105 Da | 100 mg/kg | High fat and high sugar induced T2DM rat model | Reduction of blood glucose levels and improvement of intestinal impairment | Increased gut microbiota diversity and F/B ratio; Enriched Allobaculum, Eubacterium, Anarrobiospirillum, and Holdemania; Increased cecal SCFA level | [164] |
| Fu brick tea polysaccharides | Composed of arabinose (57.4%), rhamnose (25.2%), galactose (5.1%), mannose (3.3%), galacturonic acid (3.9%) and glucuronic acid (3.1%); Mw: >8000 Da | 200 and 400 mg/kg | High-fat diet-streptozotocin-induced rat models | Relieved dyslipidemia (i.e., TC, TG, LDL-C, and HDL-C), IR, and pancreas oxidative stress | Increased Ruminococcus and Lactobacillus; Reduced Prevotella and Faecalibaculum; Elevated colonic SCFA levels | [176] |
| Fructus mori polysaccharides | Mw: 102.22 kDa, 8.71 kDa, and 5.62 kDa | 600 mg/kg | High-fat diet-streptozotocin-induced T2DM mice model | Suppressed intestinal inflammation and oxidative stress; Enhanced the intestinal barrier function | Inhibiting endotoxin-producing Shigella and promoting Allobaculum and Bifidobacterium | [177] |
| Dendrobium officinale polysaccharides | β-glucan; Mw: 8000~12,000 Da |
400 mg/kg/d | High-fat diet-induced T2DM mice model | Ameliorating IR; Fortifies intestinal barrier function | Favorable growth-promoting effects on Parabacteroides distasonis; Increased nicotinic acid level | [227] |
| Auricularia auricula polysaccharides | Composed of fucose, galactose, glucose, mannose, and glucuronic acid | 200 mg/kg/d | High-fat diet-streptozotocin-induced T2DM mice model | Reduced fasting blood glucose level; Stabilized the weight | Decreased the abundance of Enterorhabdus, Desulfovibrio, and Helicobacter, and increased the abundance of beneficial genera such as Alloprevotella, Faecalibaculum, Dubosiella | [224] |
| Sargassum fusiforme fucoidan | High sulfate (14.55%) and rich in fucose (55.67%) and galactose (20.83%); Mw: 205.8 kDa | 40 mg/kg/d | High-fat diet-streptozotocin-induced T2DM mice model | Decreased fasting blood glucose, improved glucose tolerance, decreased oxidative stress | Enriched Bacteroides, Faecalibacterium, and Blautia; Increased levels of (R)-carnitine and choline in the colon | [165] |
| Auricularia auricula-judae polysaccharides | Composed of mannose (62%), glucose (12.6%), galactose (4%), rhamnose (13.1%), xylose (4%) and fucose (3.8%) | 50 and 100 mg/kg | High-fat diet-streptozotocin-induced T2DM mice model | Decreased inflammation, liver injury, and IR; Improved glycolipid metabolism disorders by regulating the AKT and AMPK pathways | Elevated gut microbiota diversity; Increased Lactobacillus and Bacteroides; Decreased Clostridium and Allobaculum; Affected the amino acid metabolism and glycolipid metabolism pathways | [225] |
| Auricularia auricula-judae polysaccharides | Composed of arabinose, mannose, galactose, and xylose with a molar ratio of 15.59:1.52:4.76:1.0 | 200 mg/kg | High-fat diet-induced hyperlipidemia rat model | Reduced the levels of total cholesterol and LDL-C | Enriched several lower-abundance SCFA-producing bacteria such as Flavonifractor and Clostridium cluster IV | [231] |
| Ganoderma lucidum polysaccharides | Composed of arabinose (5.32%), galactose (5.47%), glucose (57.63%), xylose (0.84%), mannose (25.41%), ribose (1.95%) and rhamnose (3.38%) |
500 and 1000 mg/kg | High-fat diet-streptozotocin-induced T2DM mice model | Repaired islet cells and increased insulin secretion, promoted the liver synthesis and storage of glycogen; Improved antioxidant enzymes and IR | Decreased the F/B ratio; Enriched Lactobacillus, Bacteroides, and Ruminococcaceae; Decreased the release of endotoxins | [228] |
| Ganoderma lucidum polysaccharides | Composed of mannose, glucose, galactose, rhamnose, and arabinose in the molar ratio of 3.16:16.17:3.74:1.65:1; Mw: 13.7 kDa | 400 mg/kg | High-fat diet-streptozotocin-induced T2DM rat model | Decreased in the levels of fasting blood glucose and insulin | Reduced Aerococcus, Ruminococcus, Corynebacterium, and Proteus, and increased Blautia, Dehalobacterium, Parabacteroides, and Bacteroides; Restored the disturbed amino acids metabolism, carbohydrates metabolism | [229] |
| Lycium barbarum polysaccharides | Composed of carbohydrates (62.27%), uronic acid (25.03%), and protein (2.92%); Mw: 3.5 kDa | 50, 100, or 200 mg/kg | High-fat diet-streptozotocin-induced T2DM rat model | Alleviated the symptoms of hyperglycemia, hyperlipidemia, and IR; boosted the activities of CAT, SOD, and GSH-Px and reduced inflammation | Increasing Bacteroides, Ruminococcaceae_UCG-014, Intestinimonas, Mucispirillum, Ruminococcaceae_UCG-009 and decreasing Allobaculum, Dubosiella, Romboutsia; Increased SCFA production and decreased LPS | [232] |
| Lycium barbarum L. polysaccharides | Composed of rhamnose (8.37%), glucuronic acid (2.21%), glucose (7.95%), galactose (26.38%), xylose (7.91%) and arabinose (47.18%); Mw: 38.54 kDa | 200 mg/kg | High-fat diet-streptozotocin-induced diabetes mice model | Improved fasting blood glucose and glycated hemoglobin level and beta-cell function; guarded the intestinal barrier function | Induced Allobaculum | [233] |
| Dendrobium officinale leaf polysaccharides | Composed of glucose, mannose, glucuronic acid, and galactose at a molar ratio of 3.2:2.6:1.0:0.7; Mw: 9.91 kDa | 200 mg/kg | High-fat diet-streptozotocin-induced T2DM mice model | Ameliorated hyperglycemia, inhibited IR, reduced lipid concentration | Decreased the F/B ratio; Increased Lactobacillus, Bifidobacterium, and Akkermansia; Increased colonic SCFA levels | [234] |
| Morchella esculenta polysaccharides | Composed of mannose (5.77%), glucose (81.35%), galactose (3.543%) and arabinose (8.99%) | 200, 400, and 600 mg/kg | High-fat diet-streptozotocin-induced T2DM mice model | Regulated hyperglycemia and hyperlipidemia and improved insulin sensitivity; Improved intestinal permeability | Increased Lactobacillus, decreased Corynebacterium, and Facklamia; Increased indole biosynthesis and secondary BA biosynthesis gene expression | [235] |
| Astragalus membranaceus polysaccharides | Mw: >3000 Da | 400 mg/kg | High-fat diet-streptozotocin-induced T2DM mice model | Improved glycolipid metabolism disorders, inflammation and oxidative stress levels, and organ injury; Improved intestinal barrier | Inhibited Shigella and promoted Allobaculum and Lactobacillus | [236] |
| Dendrobium officinale polysaccharides | Composed of mannose and glucose at a molar ratio of 3.45:1 | 200 mg/kg | High fat and high sugar and streptozotocin-induced prediabetic mice model | Improved glucose, IR, and lipid metabolism | Decreased F/B ratio; Increased Bifidobacterium and Lactobacillus and decreased Colidextribacter, Helicobacter, and Mucispirillum; Increased intestinal SCFAs level and decreased LPS level | [237] |
| Huanglian polysaccharides | Composed of glucuronic acid, glucose, galactose, and arabinose, with a molar ratio of 1.0:4.4:2.4:0.6; Mw: 12.1 kDa | 200 mg/kg | High-fat diet-streptozotocin-induced T2DM mice model | Improved hyperglycemia, IR, blood lipid levels, and β-cell function | Increased Akkermansia, and decreased Aerococcus, Providencia, Pseudochrobactrum; Increased fecal butyrate level | [238] |
| Laminaria japonica polysaccharides | Composed of fucose, galactose, glucose, and mannuronic acid, with a molar ratio of 0.848:0.097:0.039:0.016; Mw: 7.32 kDa | 100 or 200 mg/kg | High fat and high sugar and streptozotocin-induced diabetic mice model | Reduced fasting blood glucose levels, insulin levels, and inflammatory factors | Increased Candidatus_Saccharimonas, Shinella, Akkermansia, and Ochrobactrum; Increased cecal SCFA level | [239] |
| Black quinoa polysaccharides | Composed of mannose (0.560%), ribose (0.418%), rhamnose (0.467%), glucuronide (1.889%), galacturonic acid (0.388%), glucose (91.169%), galactose (2.512%), xylose (0.305%), arabinose (2.031%), and fucose (0.262%); Mw: 8.087 kDa | 400 or 800 mg/kg | High-fat diet-streptozotocin-induced T2DM mice model | Ameliorated blood glucose and lipid levels and improved oxidative stress levels and liver injury levels | Decreased F/B ratio; Increased Dubosiella, Akkermansia, Faecalibaculum, and Allobaculum; Increased cecal SCFA level | [240] |
| Phellinus linteus polysaccharides | - | 300 mg/kg | High fat and high sugar and streptozotocin-induced T2DM rat model | Promoted the secretion of GLP-1, stimulated insulin secretion, and reduced blood glucose | Increased Bacteroides, Parabacteroides, and Alistioes; Increased intestinal SCFAs production and promoted conjugated BAs decomposition and the transformation of primary BAs to secondary BAs | [241] |
| Tegillarca granosa polysaccharides | Composed of mannose, glucosamine, rhamnose, glucuronic acid, galactosamine, glucose, galactose, xylose, and fucose, with a molar ratio of 1:1.38:0.87:0.53:0.52:5.37:1.38:1.05:2.40; Mw: 5.1 kDa | 200 or 400 mg/kg | High-fat diet-streptozotocin-induced T2DM mice model | Improved dyslipidemia and disorders in glucolipid metabolism, enhanced insulin sensitivity by activating the PI3K/Akt signaling pathway | Increased Allobaculum, Lachnospiraceae_NK4A136_group, Akkermansia, and Bifidobacterium; Increased fecal butyrate level | [242] |
| Glycyrrhiza uralensis polysaccharides | Composed of galactose, xylose, mannose, and glucose, with a molar ratio of 1:0.22:1.2:0.22 | 400 mg/kg | High-fat diet-streptozotocin-induced T2DM mice model | Ameliorated hyperglycemia, IR, oxidative stress, enhanced gut barrier function, and reduced liver lipid levels | Increased Akkermansia, Lactobacillus, Romboutsia, and Faecalibaculum, decreased Bacteroides, Escherichia-Shigella, and Clostridium sensu stricto 1 | [243] |
Notes: T2DM, Type 2 diabetes mellitus; IR, insulin resistance; TG, triglyceride; TC, total cholesterol; LDL-C, low-density lipoprotein cholesterol; SCFAs, short-chain fatty acids; LPS, lipopolysaccharide; BAs, bile acids; CAT, catalase; SOD, superoxide dismutase; GSH-Px, glutathione peroxidase; GLP-1, glucagon-like peptide-1; AMPK, Adenosine 5′-monophosphate (AMP)-activated protein kinase; AKT, protein kinase B; F/B ratio, the ratio of Firmicutes to Bacteroidetes.