Objectives: Probiotic supplementation often only leads to transient improvement in the gut microbiome. Potential prebiotics, such as the oligosaccharide-rich varieties of Dioscorea esculenta tubers, can potentially bridge the gap between supplementation and persistent colonization. Thus, this study aimed to assess the ability of D. esculenta tubers to promote the growth of probiotic Lactobacillus sp. in vitro selectively.

Methods: The prebiotic activity of the selected varieties of Dioscorea esculenta tubers was evaluated via compe titive growth assay, wherein the ratios of probiotic Lactobacillus sp. over enterotoxigenic Escherichia coli (ETEC) or "prebiotic ratios" were compared following treatment.

Results: Negative control (0.9% NaCl solution) produced a ratio of 0.88, Lowland and Highland varieties produced ratios of 1.26 and 1.29, respectively, and positive control (inulin) produced 1.54. The two varieties had comparable ratios to one another (p > 0.05), and significantly higher ratios than the negative control (p < 0.05). Both varieties have significant prebiotic activity. Compared to inulin, the two varieties' prebiotic activity was 84% as effective.

Conclusion: Overall, the tubers promoted the growth of Lactobacillus sp. over ETEC. The crude tuber samples, given their availability and affordability, can be easily integrated into the local diet to contribute to the improvement of the general population's health.

Enterotoxigenic Escherichia coli ; Inulin ; Lactobacillus ; Prebiotics

As a type of prebiotics and dietary fiber, inulin performs plenty of significant physiological functions and is applied in food and pharmaceutical fields. Inulosucrase from microorganisms can use sucrose as the substrate to synthesize inulin possessing higher molecular weight than that from plants. In this work, a hypothetical gene coding inulosucrase was selected from the GenBank database. The catalytic domain was remained by N- and C- truncation strategies, constructing the recombinant plasmid. The recombinant plasmid was expressed in E. coli expression system, and after purifying the crude enzyme by Ni²⁺ affinity chromatography, a recombinant enzyme with a molecular weight of approximately 65 kDa was obtained. The optimal pH and temperature of the recombinant enzyme were 5.5 and 45 °C, respectively, when sucrose was used as the sole substrate. The activity of this enzyme was inhibited by various metal ions at different degrees. After purifying the produced polysaccharide, nuclear magnetic resonance analysis was used to determine that the polysaccharide was inulin connected by β-(2,1) linkages. Finally, the conditions for the production of inulin were optimized. The results showed that the inulin production reached the maximum, approximately 287 g/L after 7 h, when sucrose concentration and enzyme dosage were 700 g/L and 4 U/mL, respectively. The conversion rate from sucrose to inulin was approximately 41%.
Escherichia coli/genetics* ; Hexosyltransferases/genetics* ; Inulin ; Oligosaccharides ; Sucrose

PURPOSE: The aim of this study was to identify the minimally meaningful dosage of inulin leading to a prebiotic effect in Indonesian infants. METHODS: In a randomized controlled double-blinded, parallel, 3-arm intervention study, 164 healthy formula-fed infants aged 3 to 5 months first obtained formula-A (without inulin) during a 4-week adaptation period. Subsequently, 142 subjects were subjected to a 4-week feeding period by administering either formula-A (no inulin), formula-B (0.2 g/100 mL inulin) or formula-C (0.4 g/100 mL inulin). The primary outcome parameter was %-bifidobacteria in faecal samples determined using quantitative polymerase chain reaction analyses. Secondary outcome parameters were faecal %-lactobacilli, pH and stool frequency, and consistency. Growth and tolerance/adverse effects were recorded as safety parameters. RESULTS: Typical %-bifidobacteria and %-lactobacilli at the end of the adaptation period in the study population were 14% and 2%, respectively. For faecal pH, significant differences between formula groups A vs. C and A vs. B were found at the end of the intervention period. Testing for differences in faecal %-bifidobacteria and %-lactobacilli between groups was hampered by non-normal data set distributions; no statistically significant differences were obtained. Comparisons within groups revealed that only in formula group C, all the three relevant parameters exhibited a significant effect with an increase in faecal %-bifidobacteria and %-lactobacilli and a decrease in pH. CONCLUSION: A consistent prebiotic effect along with a decrease in pH and increase in %-bifidobacteria and %-lactobacilli was found only in the group administered 0.4 g inulin/100 mL.
Dataset ; Gastrointestinal Microbiome ; Humans ; Hydrogen-Ion Concentration ; Infant Formula ; Infant* ; Inulin* ; Polymerase Chain Reaction ; Prebiotics*

Inulin has been used as a prebiotic to alleviate glucose and lipid metabolism disorders in mice and humans by modulating the gut microbiota. However, the mechanism underlying the alleviation of metabolic disorders by inulin through interactions between the gut microbiota and host cells is unclear. We use ob/ob mice as a model to study the effect of inulin on the cecal microbiota by 16S rRNA gene amplicon sequencing and its interaction with host cells by transcriptomics. The inulin-supplemented diet improved glucose and lipid metabolism disorder parameters in ob/ob mice, alleviating fat accumulation and glucose intolerance. The α diversity of gut microbial community of ob/ob mice was reduced after inulin treatment, while the β diversity tended to return to the level of wild type mice. Interestingly, Prevotellaceae UCG 001 (family Prevotellaceae) was obviously enriched after inulin treatment. A comparative analysis of the gene expression profile showed that the cecal transcriptome was changed in leptin gene deficiency mice, whereas the inulin-supplemented diet partially reversed the changes in leptin gene-related signaling pathways, especially AMPK signaling pathway, where the levels of gene expression became comparable to those in wild type mice. Further analysis indicated that Prevotellaceae UCG 001 was positively correlated with the AMPK signaling pathway, which was negatively correlated with markers of glycolipid metabolism disorders. Our results suggest that the inulin-supplemented diet alleviates glucose and lipid metabolism disorders by partially restoring leptin related pathways mediated by gut microbiota.
AMP-Activated Protein Kinases ; metabolism ; Animals ; Cecum ; enzymology ; metabolism ; microbiology ; Gastrointestinal Microbiome ; drug effects ; Inulin ; therapeutic use ; Leptin ; genetics ; Male ; Metabolic Diseases ; drug therapy ; enzymology ; metabolism ; microbiology ; Mice ; Mice, Obese ; Prebiotics ; Signal Transduction ; drug effects ; Transcriptome

BACKGROUND/AIMS: Race and ethnicity are important determinants when estimatingglomerular filtration rate (GFR). The Korean coefficients for the isotope dilution mass spectrometry (IDMS) Modification of Diet in Renal Disease (MDRD) Study equations were developed in 2010. However, the coefficients have not been validated. The aim of this study was to validate the performance of the Korean coefficients for the IDMS MDRD Study equations. METHODS: Equation development and validation were performed in separate groups (development group, n = 147 from 2008 to 2009; validation group, n = 125 from 2010 to 2012). We compared the performance of the original IDMS MDRD equations and modified equations with Korean coefficients. Performance was assessed by comparing correlation coefficients, bias, and accuracy between estimated GFR and measured GFR, with systemic inulin clearance using a single injection method. RESULTS: The Korean coefficients for the IDMS MDRD equations developed previously showed good performance in the validation group. The new Korean coefficients for the four- and six-variable IDMS MDRD equations using both the development and validation cohorts were 1.02046 and 0.97300, respectively. No significant difference was detected for the new Korean coefficients, in terms of estimating GFR, between the original and modified IDMS MDRD Study equations. CONCLUSIONS: The modified equations with Korean coefficients for the IDMS MDRD Study equations were not superior to the original equations for estimating GFR. Therefore, we recommend using the original IDMS MDRD Study equation without ethnic adjustment in the Korean population.
Adult ; Aged ; *Asian Continental Ancestry Group ; Biomarkers/blood ; Case-Control Studies ; Chromatography, High Pressure Liquid ; Creatinine/blood ; Female ; *Glomerular Filtration Rate ; Humans ; Indicator Dilution Techniques ; Inulin/administration & dosage/blood ; Kidney/*physiopathology ; Male ; Mass Spectrometry ; Middle Aged ; *Models, Biological ; Oligosaccharides/administration & dosage/blood ; Predictive Value of Tests ; Renal Insufficiency, Chronic/blood/*diagnosis/ethnology/physiopathology ; Reproducibility of Results ; Republic of Korea

Jerusalem artichoke (JA) mainly consists of inulin. In many experimental studies, inulin has been shown to be beneficial for decreasing glucose level. Therefore, JA is lately attracting wide attention as an anti-diabetic food. Therefore, many patients ingest JA in extract form. However, there are no published clinical studies in patients with diabetes to demonstrate benefit from the use of inulin-type fructans. We experienced a diabetes inpatient with acute hyperglycemia associated with JA. We could not control the patient's blood glucose in spite of addition and increment of insulin. We found that she had taken extracts of JA and recommended cessation. After discontinuing JA extracts, her blood glucose was well controlled in spite of discontinuation of insulin. Thus, in this patient, JA had actually increased blood glucose. We suggest that JA may be dangerous for use in diabetic patients.
Blood Glucose ; Diabetes Mellitus ; Diabetes Mellitus, Type 2* ; Fructans ; Glucose ; Helianthus* ; Humans ; Hyperglycemia* ; Inpatients ; Insulin ; Inulin

There is growing interest in using food choice/dietary change to influence clinical outcomes in patients with irritable bowel syndrome (IBS). The low fermentable oligo-, di-, mono-saccharides, and polyols (FODMAPs) diet is an evidence-based approach that is gaining popularity in many Western countries. The low FODMAP diet is based on restricting dietary intake of short chain carbohydrates that are slowly absorbed or indigestible and not absorbed during passage through the small intestine. These are collectively described as "FODMAPs" and comprise oligosaccharides (mostly fructans, galacto-oligosaccharides), sugar polyols, fructose in excess of glucose, and lactose in lactose malabsorbers. The general strategy of the diet is to avoid foods high in FODMAPs and replace them with foods low in FODMAPs, with long-term restriction limited to what is required to control symptoms. The likely mechanism of action is minimisation of the stimulation of mechanoreceptors exerted by distension of the intestinal lumen with water from osmotic effects and gases from bacterial fermentation in those with visceral hypersensitivity. The success of this dietary approach greatly depends on detailed knowledge about the FODMAP composition of food commonly consumed in that country. While the content of foods associated with East and Southeast Asian cuisines has not been fully explored, major high FODMAP sources are frequently used and include onion, garlic, shallots, legumes/pulses, and wheat-based products. Thus, this dietary approach holds great promise in treating IBS patients in East and Southeast Asia. The aim of this review is to highlight how the diet is implemented, its efficacy, and troublesome ingredients frequently used in Asian dishes.
Asia ; Asia, Southeastern* ; Asian Continental Ancestry Group ; Carbohydrates ; Diet* ; Fermentation ; Fructans ; Fructose ; Garlic ; Gases ; Glucose ; Humans ; Hypersensitivity ; Intestine, Small ; Irritable Bowel Syndrome ; Lactose ; Mechanoreceptors ; Oligosaccharides ; Onions ; Shallots ; Water

To improve the inulinase application in biotechnology, the characteristic of inulinase from Kluyveromyces marxianus YX01 was investigated. The inu gene of K. marxianus YX01 was transformed into Pichiapastoris GS115 host cells with molecular biology techniques. Then we achieved the heterologous expression of exo-inulinase whose molecular mass was about 86.0 kDa by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). Furthermore, six His-tag was added to the inulinase and a two-step method was applied in the purification of inulinase, including concentration via dialysis by polyethylene glycol 20 000 and metal Ni-NTA Agarose affinity adsorption. The purification factor of purified protein was 3.6 and the recovery rate of enzyme activity was 33.1%. We characterized the purified inulinase. The optimum temperature was 60 degrees C and pH was 4.62. When inulin and sucrose were used as substrates, the K(m) and V(max) values were 80.53 g/L vs 4.49 g/(L x min) and 183.10 g/L vs 20.20 g/(L x min), respectively. In addition, metal ions including Mn2+, Ca2+, Cu2+, Zn2+ and Fe2+ exhibited different degrees of inhibition on the enzyme activity, and Cu2+, Zn2+ and Fe2+ exhibited the most significant inhibition. Our findings might lay a good foundation for industrial application of inulinase.
Glycoside Hydrolases ; chemistry ; genetics ; Industrial Microbiology ; Inulin ; Kluyveromyces ; enzymology ; genetics ; Pichia ; Sucrose ; Temperature

The idea of body compartments has its origins in physiology and antedates their use in both physiologically-based predictive pharmacokinetic models and in the simpler compartmental models used to analyze pharmacokinetic data. Whereas physiologically-based pharmacokinetics has evolved to use increasingly sophisticated organ-based models, most compartmental models for data analysis are used without regard for their underlying physiological basis. However, detailed analysis of inulin and urea kinetics has offered some understanding of the physiological basis underlying some three-compartment pharmacokinetic models. In addition, these simple models have yielded new insight into physiological phenomena.
Inulin ; Kinetics ; Pharmacokinetics ; Physiological Phenomena ; Physiology ; Statistics as Topic ; Urea

OBJECTIVETo observe the therapeutic effect of inulin on enteric hyperoxaluria in rats.

METHODSIn experimental A, 24 healthy male Sprague-Dawley rats received an oxalate-free diet on day 1, a high-oxalate diet (oxalate, 74.82 mg/100 g feed stuffs) on days 2 and 3, and plus 2 g inulin to each rat on day 3. The 24-hour urinary volume, concentrations of urinary oxalate and urine creatinine were measured, and 24-hour urinary oxalate excretion was calculated. In experimental B, 24 healthy male Sprague-Dawley rats were equally randomized into control group and inulin group, Each rat received a high oxalate diet (oxalate, 74.82 mg/100 g feedstuffs), and plus 2 g inulin in inulin group. The 24-hour urinary oxalate excretion was calculated in both two groups.

RESULTSIn experimental A, the 24-hour urinary oxalate excretion varied with time (F=11.481, P=0.035). The 24-hour urinary oxalate excretion significantly increased on day 2 compared with that on day 1 (P=0.026) and day 3 (P=0.037); it significantly increased on day 3 compared with day 1 (P=0.004). In experimental B, the 24-hour urinary oxalate excretion significantly decreased in inulin group compared with the control (P=0.011).

CONCLUSIONInulin may have potential therapeutic effect on enteric hyperoxaluria in rats.

Animals ; Disease Models, Animal ; Hyperoxaluria ; drug therapy ; Inulin ; therapeutic use ; Male ; Rats ; Rats, Sprague-Dawley ; Treatment Outcome