Determination of inulin-type fructo-oligosaccharides in inulin by HPLC-ELSD

To develop an HPLC-ELSD method for the determination of nine inulin-type fructo-oligosaccharides in inulin,the HPLC-ELSD system consisted of Waters XBridge■ Amide column(4.6 mm×250 mm,5μm)with a gradient elution mobile phase consisting of acetonitrile and water at a flow rate of 1.2 mL/min at 30°C.The detector was an Agilent Technologies 380-ELSD.The drift tube temperature for the ELSD was set at 55°C with a nitrogen flow rate of 1.8 L/min.The injection volume was 15μL.The results showed that the detection range for the nine inulin-type fructo-oligosaccharides was 3.81–30.60μg R^(2)=0.99969 for kestose,3.73–29.97μg R^(2)=0.99981 for nystose,3.82–30.69μg R^(2)=0.99993 for fructosylnystose,3.80–30.48μg R^(2)=0.99995 for GF5,3.73–29.96μg R^(2)=0.99993 for GF6,3.78–30.30μg R^(2)=0.99983 for GF7,3.82–30μg R^(2)=0.99989 for GF8,3.71–29.80μg R^(2)=0.99974 for GF9,3.61–29.00μg R^(2)=0.99970 for GF10,respectively.The recovery of the nine oligosaccharides ranged between 96.48%–100.84%(n=6).The method was simple,accurate,and reproducible that it could be used as an analytical method for evaluating the quality of inulin effectively.

Effect of cooked rice with added fructo-oligosaccharide on faecal microorganisms investigated by in vitro digestion and fermentation

In the present study,the effects of cooked rice(CR)with added fructo-oligosaccharide(FOS)on faecal flora were studied by a simulated in vitro digestion and fermentation method.The total carbohydrate content,p H,and s hort-chain fatty acids(SCFAs)were determined during in vitro digestion and fermentation.The change in the bacterial phase distribution after the fermentation was also analysed.The results showed that t he total carbohydrate content of the CR with added FOS(FCR)significantly decreased during the simulated digestion.Meanwhile,the p H of the FCR decreased and the SCFAs concentration increased significantly compared to those of the CR during the simulated fermentation.In addition,the FCR showed the advantage of promoting beneficial bacteria,such as Bifidobacterium and Lactobacillus,and inhibiting harmful bacteria,such as Bacteroides and Klebsiella compared to the CR.Therefore,the FOS as a prebiotic could be recommended to produce the high-quality healthy rice food.

Fructo-oligosaccharide intensifies visceral hypersensitivity and intestinal inflammation in a stress-induced irritable bowel syndrome mouse model

AIM To determine whether fructo-oligosaccharide(FOS) affects visceral sensitivity, inflammation, and production of intestinal short-chain fatty acids(SCFA) in an irritable bowel syndrome(IBS) mouse model.METHODS Mice were randomly assigned to daily oral gavage of saline solution with or without FOS(8 g/kg body weight) for 14 d. Mice were further assigned to receive either daily one-hour water avoidance stress(WAS) or sham-WAS for the first 10 d. After 2 wk, visceral sensitivity was measured by abdominal withdrawal reflex in response to colorectal distension and mucosal inflammation was evaluated. Gas chromatography, real-time reverse transcription PCR, and immunohistochemistry assays were used to quantify cecal concentrations of SCFA, intestinal cytokine expression, and number of intestinal mast cells per high-power field(HPF), respectively.RESULTS Mice subjected to WAS exhibited visceral hypersensitivity and low-grade inflammation. Among mice subjected to WAS, FOS increased visceral hypersensitivity and led to higher cecal concentrations of acetic acid(2.49 ± 0.63 mmol/L vs 1.49 ± 0.72 mmol/L, P < 0.05), propionic acid(0.48 ± 0.09 mmol/L vs 0.36 ± 0.05 mmol/L, P < 0.01), butyric acid(0.28 ± 0.09 mmol/L vs 0.19 ± 0.003 mmol/L, P < 0.05), as well as total SCFA(3.62 ± 0.87 mmol/L vs 2.27 ± 0.75 mmol/L, P < 0.01) compared to saline administration. FOS also increased ileal interleukin(IL)-23 mR NA(4.71 ± 4.16 vs 1.00 ± 0.99, P < 0.05) and colonic IL-1β mR NA(2.15 ± 1.68 vs 0.88 ± 0.53, P < 0.05) expressions as well as increased mean mast cell counts in the ileum(12.3 ± 2.6 per HPF vs 8.3 ± 3.6 per HPF, P < 0.05) and colon(6.3 ± 3.2 per HPF vs 3.4 ± 1.2 per HPF, P < 0.05) compared to saline administration in mice subjected to WAS. No difference in visceral sensitivity, intestinal inflammation, or cecal SCFA levels was detected with or without FOS administration in mice subjected to sham-WAS.CONCLUSION FOS administration intensifies visceral hypersensitivity and gut inflammation in stress-induced IBS mice, but not in the control mice, and is also associated with increased intestinal SCFA production.

Identification of carbohydrate in Polygonatum sibiricum:fructo-oligosaccharide was a major component

Polygonatum sibiricum,famous for its physiological activities,is a popular Chinese food and a traditional Chinese herb containing many carbohydrates as the main component.However,except for most reported polysaccharides,other detailed compositions of carbohydrates are still not clear.To verify the controversial existence of starch and investigate other components,especially oligosaccharides,we used iodine–potassium iodide colorimetric detection and enzymatic hydrolysis to determine starch.Then,oligosaccharides were analyzed by thin-layer chromatography,gel permeation chromatography,high-performance anion exchange chromatography with pulsed amperometric detection,and hydrophilic interaction chromatography–electrospray tandem mass spectrometry.The results showed that the rhizome of P.sibiricum lacked starch,and fructooligosaccharides were the main component,accounting for approximately 28.95%.Oligosaccharides with degrees of polymerization above 10 were the most abundant components.This study clearly illustrated the unknown carbohydrate components of the Polygonatum rhizome,promoting its functional value with new evidence.

Dietary citrus pectin drives more ileal microbial protein metabolism and stronger fecal carbohydrate fermentation over fructooligosaccharide in growing pigs

Fructo-oligosaccharide(FOS)and pectin are known soluble dietary fibers and can influence gut microbiota and consequently modulate gut health.To understand the differential impact patterns of pectin vs.FOS in modulating gut microbiota in the small and large intestine,an ileal-cannulated pig model was adopted to compare the temporal and spatial effects of FOS and citrus pectin(CP)on the gut microbiota.Sixteen terminal ileal-cannulated pigs were randomly divided into 2 groups and fed with a standard diet supplemented with either 3% FOS or 3% CP for 28 d.The CP group and FOS group showed different microbial composition,especially in the feces,with time and location as major factors affecting microbiota in the CP group,and with only location contribution in the FOS group.In the feces,relative to the FOS group,the CP group showed higher abundance of Christensenellaceae R-7 group and Ruminococcaceae UCG-010 and lower abundance of Mitsuokella and Olsenella(adjusted P<0.05),a higher level of shortchain fatty acids and a lower level of lactate at both d 14 and 25(P<0.05),and more copy numbers of genes encoding key enzymes related to propionate(mmd A)and butyrate(BCo AT)production and lactate utilization(Lcd A)(P<0.05),indicating a greater degree of microbial carbohydrate fermentation.In the ileum,as compared with FOS,CP increased the bacteria with high capability of fermenting amino acids,including Escherichia-Shigella and Klebsiella(adjusted P<0.05),and the expression of enzymes responsible for amino acid fermentation(i.e.lysine decarboxylase),as well as the amino acid fermentation products(cadaverine and tyramine)(P<0.05),indicating a greater degree of amino acid fermentation.Overall,our results highlight a differential dynamic impact of dietary CP vs.FOS on microbial composition and metabolism in the gut.The dietary CP has a stronger ability to promote microbial amino acid fermentation in the ileum and carbohydrate fermentation in the feces than FOS.These findings provide a new insight into the role of different fibers in gut nutrition and guidelines for the choice of fibers in manipulating gut health.