Barley beta-glucans varying in molecular mass and oligomer structure affect cecal fermentation and microbial composition but not blood lipid profiles in hypercholesterolemic rats.
Study Goal
The researchers aimed to determine how molecular mass and oligomer structure of barley β-glucans affect plasma lipids and gut parameters in hypercholesterolemic rats.
Results Summary
All diets, including control and β-glucan-supplemented diets, reduced plasma triacylglycerol and cholesterol levels. β-glucan diets increased cecal short-chain fatty acid production and altered gut microbiota composition, but did not show additional lipid-lowering effects compared to the control.
Population
Hypercholesterolemic rats
Effective Dosage
6.5-7.5% of the diet
Duration
4 weeks
Interactions
None mentioned
| Intervention | Direction | Endpoint | Population | Dosage | Impact | Claim # |
|---|---|---|---|---|---|---|
All four diets (control, glucagel, lowBG or mediumBG) | decrease | plasma triacylglycerol and cholesterols | hypercholesterolemic rats | - | reduced | #1 |
The BG diets | increase | cecal production of short-chain fatty acids (SCFAs) | hypercholesterolemic rats | - | increased | #2 |
The glucagel and lowBG diets | increase | number of Bifidobacterium in the cecum | hypercholesterolemic rats | - | stimulated | #3 |
The mediumBG diet | decrease | numbers of both Bacteroides/Prevotella and Lactobacillus in the cecum | hypercholesterolemic rats | - | reduced | #4 |
barley BGs at 6.5-7.5% of the diet independent of molecular mass and oligomer block structure | no change | blood cholesterol and triacylglycerol levels | hypercholesterolemic rat model | - | showed no additional effect | #5 |
There is an unmet need for appealing and functional barley β-glucan (BG) food matrices that can provide sufficient and active BG doses to consumers. We investigated how molecular mass and oligomer structure important for BG food and health properties affected plasma lipids and gut parameters in hypercholesterolemic rats. Following 3 weeks on a high-cholestrol diet, rats were given a high-cholesterol diet supplemented with either cellulose (control) or purified barley BGs with low (100 or 150 kDa; glucagel or lowBG, respectively) or medium (530 kDa; mediumBG) molecular masses varying in cellotriosyl/cellotetraosyl oligomer ratio for 4 weeks. All four diets (control, glucagel, lowBG or mediumBG) reduced plasma triacylglycerol and cholesterols from week 3 to 7. The BG diets increased cecal production of short-chain fatty acids (SCFAs) compared to the control diet. The glucagel and lowBG diets stimulated the number of Bifidobacterium in the cecum, whereas the mediumBG diet reduced numbers of both Bacteroides/Prevotella and Lactobacillus in the cecum compared to the control diet. In conclusion, barley BGs at 6.5-7.5% of the diet independent of molecular mass and oligomer block structure showed no additional effect compared to the control treatment on blood cholesterol and triacylglycerol levels in this hypercholesterolemic rat model. Furthermore, the cecal fermentation pattern and microbial composition did not seem to affect plasma lipid composition.