ABSTRACT
In vitro fermentation of polysaccharide from Cyclocarya paliurus leaves by human fecal inoculums was investigated by determining the changes in contents of neutral and reducing sugar and pH value, consumption of monosaccharide and production of short-chain fatty acids (SCFAs). During fermentation, the content of neutral sugar and reducing sugar decreased as fermentation time increased except that the content of reducing sugar increased within the fermentation time 0.5h. The pH value significantly dropped from 7.2 to 6.04. Remarkably, the greatest yields and the fastest consumption of galacturonic acid were found and the yield of glucose and arabinose were relatively high. The dominant SCFAs, which were acetic acid, propionic acid and n-butyric acid, significantly increased. These results showed that polysaccharide was partly fermented, glycosidic bonds with galacturonic acid being more susceptible to be attacked by gut bacteria and galacturonic acid might be deemed as the main producer of acetic acid.
Subject(s)
Feces/microbiology , Juglandaceae/chemistry , Plant Leaves/metabolism , Polysaccharides/chemistry , Polysaccharides/metabolism , Acetic Acid/metabolism , Arabinose/metabolism , Fatty Acids, Volatile/analysis , Fatty Acids, Volatile/metabolism , Fermentation , Hexuronic Acids/metabolism , Humans , Hydrogen-Ion Concentration , Propionates/metabolismABSTRACT
White rice porridge and mixed grain porridge, which are often consumed in many countries, were used as two models to evaluate the effects of gum arabic on glucose levels and microbial short-chain fatty acids (SCFA). Gum arabic was incorporated into the two porridges individually. Apparent viscosity of the two porridges was significantly increased, and their glucose productions during gastrointestinal digestion were notably lowered (p < 0.05). Diffused glucose amount was significantly decreased after gum arabic addition (p < 0.05). Furthermore, blood glucose rise after oral administration of porridges in mice was considerably lowered after fortified with gum arabic (p < 0.05). Microbial SCFA production during in vitro fermentation of porridges was significantly increased after gum arabic addition, which may also have beneficial effects on reducing postprandial glycemic response. Therefore, gum arabic may be a helpful ingredient, which could be added in porridges to have benefits for the reduction of postprandial glycemic response.
Subject(s)
Bacteria/metabolism , Edible Grain/metabolism , Fatty Acids, Volatile/metabolism , Food Additives/metabolism , Glucose/metabolism , Gum Arabic/metabolism , Microbiota , Oryza/metabolism , Animals , Bacteria/genetics , Bacteria/isolation & purification , Cooking , Digestion , Edible Grain/chemistry , Food Additives/chemistry , Gastrointestinal Tract/metabolism , Gastrointestinal Tract/microbiology , Gum Arabic/chemistry , Male , Mice , Oryza/chemistry , Postprandial Period , ViscosityABSTRACT
The saliva, gastric and intestinal digestion of polysaccharide from Plantago asiatica L. seeds was investigated in vitro. It was found that salivary amylase had no effect on the polysaccharide; however, the polysaccharide was influenced in later gastrointestinal digestion. A steady decrease in molecular weight (M(w)) of the polysaccharide from 1903.1±93.0 to 4.7±0.2 kDa was observed as digestion time increased. Meanwhile, the reducing ends were increased from 0.157±0.009 to 0.622±0.026 mM, indicating the decrease of M(w) may due to the breakdown of glycosidic bonds. In addition, there was no monosaccharide released throughout the whole digestion period, suggesting that the gastrointestinal digestion did not result in a production of free monosaccharide. These results may provide some information on the digestion of polysaccharide from P. asiatica L. in vitro, and may contribute to the methods of studying the digestion of other carbohydrates.
Subject(s)
Biomimetics , Gastric Mucosa/metabolism , Intestinal Mucosa/metabolism , Plantago/chemistry , Polysaccharides/metabolism , Saliva/metabolism , Seeds/chemistry , Digestion , Humans , Intestines/physiology , Molecular Weight , Monosaccharides/analysis , Polysaccharides/chemistry , Stomach/physiologyABSTRACT
Mice (20.0 ± 2.0 g, n = 48 per group) were given 30 days oral administration of polysaccharide from Plantago asiatica L. seeds at the dose of 0.4 g/kg body weight by gavage to investigate the effects of the polysaccharide on mouse colon. Results showed that the concentrations of total short-chain fatty acids (SCFA), acetic, propionic, and n-butyric acids in mouse colonic content of polysaccharide treated group were all significantly higher than that of control group (water) (p < 0.05). In addition, moisture of mouse colonic content of polysaccharide treated group was also notably higher than that of the control group (p < 0.05) indicating the intake of polysaccharide from P. asiatica L. resulted in a stronger water-holding capacity for colonic content throughout the experimental period. Furthermore, a decreased pH (from 7.5 ± 0.1 to 7.2 ± 0.1) was observed in mouse colon of the polysaccharide treated group compared with the control group (pH from 7.5 ± 0.1 to 7.5 ± 0.1). These results suggested that the intake of the polysaccharide from P. asiatica L. might be beneficial for the colon health.
