Values for the Digestibility of Pea Protein Isolate or Casein Amino Acids Determined using the Dual Isotope Method Are Not Similar to Those Derived with the Standard Ileal Balance Method in Healthy Volunteers

BACKGROUND

The measurement of ileal amino acid (AA) digestibility is invasive and inappropriate when applied to vulnerable populations. The dual isotope method has been developed over the past 5 y as an alternative method.

OBJECTIVE

The aim of this work was to compare the indispensable amino acid (IAA) digestibility values of 2 different proteins obtained using the dual isotope and the standard ileal balance methods in the same subjects.

METHODS

Fifteen healthy adults completed the study. Over 4 h, they ingested 9 successive portions of mashed potatoes containing the test protein (pea protein or casein) labeled intrinsically with 15N and 2H, and a 13C-free AA mixture as a reference for the dual isotope method. Plasma was sampled regularly over the 8-h postprandial period, whereas the ileal digesta was collected continuously via a naso-ileal tube. Isotopic enrichments (15N and 13C) were measured in the digesta for the direct determination of ileal IAA digestibility, whereas plasma enrichments (2H and 13C) were measured to determine IAA digestibility using the dual isotope method.

RESULTS

The 4-h repeated meal procedure enabled the almost complete digestion of test proteins at 8 h and the attainment of a plasma isotopic plateau between 2.5 and 4 h. These conditions were necessary to perform the ileal balance and dual isotope methods simultaneously. For pea protein, the mean IAA digestibility was similar between the 2 methods, but significant differences (from 10% to 20%) were observed for individual IAA values. For casein, IAA digestibility was significantly lower with the dual isotope method for all the IAA analyzed.

CONCLUSIONS

Under our experimental conditions, the degree of agreement between the dual isotope and ileal balance methods varied among AAs and depended on the protein source. Further research is needed to validate the dual isotope method. This study was registered at clinicaltrials.gov as NCT04072770.

Improvement of energy metabolism associated with NUTRIOSE® soluble fiber, a dietary ingredient exhibiting prebiotic properties, requires intestinal gluconeogenesis

While the prevalence of obesity progresses worldwide, the consumption of sugars and dietary fiber increases and decreases, respectively. In this context, NUTRIOSE® soluble fiber is a plant-based food ingredient with beneficial effects in Humans. Here, we studied in mice the mechanisms involved, particularly the involvement of intestinal gluconeogenesis (IGN), the essential function in the beneficial effects of dietary fibers. To determine whether NUTRIOSE® exerts its beneficial effects via the activation of IGN, we studied the effects of dietary NUTRIOSE® on the development of obesity, diabetes and non-alcoholic fatty liver disease (NAFLD), which IGN is able to prevent. To assert the role of IGN in the observed effects, we studied wild-type (WT) and IGN-deficient mice. In line with our hypothesis, NUTRIOSE® exerts metabolic benefits in WT mice, but not in IGN-deficient mice. Indeed, WT mice are protected from body weight gain and NAFLD induced by a high calorie diet. In addition, our data suggests that NUTRIOSE® may improve energy balance by activating a browning process in subcutaneous white adipose tissue. While the gut microbiota composition changes with NUTRIOSE®, this is not sufficient in itself to account for the benefits observed. On the contrary, IGN is obligatory in the NUTRIOSE® benefits, since no benefit take place in absence of IGN. In conclusion, IGN plays a crucial and essential role in the set-up of the beneficial effects of NUTRIOSE®, highlighting the interest of the supplementation of food with healthy ingredients in the context of the current obesity epidemic.

Compared with Milk Protein, a Wheat and Pea Protein Blend Reduces High-Fat, High-Sucrose Induced Metabolic Dysregulations while Similarly Supporting Tissue Protein Anabolism in Rats

BACKGROUND

Plant proteins (PPs) have been associated with better cardiovascular health than animal proteins (APs) in epidemiological studies. However, the underlying metabolic mechanisms remain mostly unknown.

OBJECTIVES

Using a combination of cutting-edge isotopic methods, we aimed to better characterize the differences in protein and energy metabolisms induced by dietary protein sources (PP compared with AP) in a prudent or western dietary context.

METHODS

Male Wistar rats (n = 44, 8 wk old) were fed for 4.5 mo with isoproteic diets differing in their protein isolate sources, either AP (100% milk) or PP (50%:50% pea: wheat) and being normal (NFS) or high (HFS) in sucrose (6% or 15% kcal) and saturated fat (7% or 20% kcal), respectively. We measured body weight and composition, hepatic enzyme activities and lipid content, and plasma metabolites. In the intestine, liver, adipose tissues, and skeletal muscles, we concomitantly assessed the extent of amino acid (AA) trafficking using a ¹⁵N natural abundance method, the rates of macronutrient routing to dispensable AA using a ¹³C natural abundance method, and the metabolic fluxes of protein synthesis (PS) and de novo lipogenesis using a ²H labeling method. Data were analyzed using ANOVA and Mixed models.

RESULTS

At the whole-body level, PP limited HFS-induced insulin resistance (-27% in HOMA-IR between HFS groups, P < 0.05). In the liver, PP induced lower lipid content (-17%, P < 0.01) and de novo lipogenesis (-24%, P < 0.05). In the different tissues studied, PP induced higher AA transamination accompanied by higher routings of dietary carbohydrates and lipids toward dispensable AA synthesis by glycolysis and β-oxidation, resulting in similar tissue PS and protein mass.

CONCLUSIONS

In growing rats, compared with AP, a balanced blend of PP similarly supports protein anabolism while better limiting whole-body and tissue metabolic dysregulations through mechanisms related to their less optimal AA profile for direct channeling to PS.

Effect of Resistant Dextrin on Intestinal Gas Homeostasis and Microbiota

Previous studies have shown that a resistant dextrin soluble fibre has prebiotic properties with related health benefits on blood glucose management and satiety. Our aim was to demonstrate the effects of continuous administration of resistant dextrin on intestinal gas production, digestive sensations, and gut microbiota metabolism and composition. Healthy subjects (n = 20) were given resistant dextrin (14 g/d NUTRIOSE^®, Roquette Frères, Lestrem, France) for four weeks. Outcomes were measured before, at the beginning, end, and two weeks after administration: anal evacuations of gas during daytime; digestive perception, girth, and gas production in response to a standard meal; sensory and digestive responses to a comfort meal; volume of colonic biomass by magnetic resonance; taxonomy and metabolic functions of fecal microbiota by shotgun sequencing; metabolomics in urine. Dextrin administration produced an initial increase in intestinal gas production and gas-related sensations, followed by a subsequent decrease, which magnified after discontinuation. Dextrin enlarged the volume of colonic biomass, inducing changes in microbial metabolism and composition with an increase in short chain fatty acids-producing species and modulation of bile acids and biotin metabolism. These data indicate that consumption of a soluble fibre induces an adaptative response of gut microbiota towards fermentative pathways with lower gas production.

Real ileal amino acid digestibility of pea protein compared to casein in healthy humans: a randomized trial

BACKGROUND

It is necessary to propose plant alternatives to animal proteins that are of good nutritional quality. Pea is a good candidate owing to its high protein content and its well-balanced amino acid (AA) profile.

OBJECTIVES

This study aimed to assess the real ileal AA and nitrogen digestibility (RIDAA and RIDN) of pea protein isolate as compared to milk casein in humans. It also aimed to evaluate their nutritional quality through calculation of the digestible indispensable amino acid score (DIAAS) and to determine the net postprandial protein utilization (NPPU).

METHODS

Fifteen healthy volunteers were included in a randomized, single-blinded, 2-arm, parallel-design trial. They were equipped with a naso-ileal tube. They ingested the test meals, which consisted of 9 successive portions of mashed potatoes containing either pea protein or casein, intrinsically labeled with nitrogen 15. Ileal content, plasma, and urine samples were collected regularly over an 8-h postprandial period.

RESULTS

The mean RIDAA values were 93.6% ± 2.9% for pea protein and 96.8% ± 1.0% for casein, with no difference between the sources (P = 0.22). Leucine, valine, lysine, and phenylalanine were significantly less digestible in pea than in casein. The RIDN values were 92.0% ± 2.7% and 94.0% ± 1.7% for pea protein and casein, respectively, and were not different (P = 0.11). The DIAAS was 1.00 for pea protein and 1.45 for casein. The NPPU was 71.6% ± 6.2% and 71.2% ± 4.9% for pea protein and casein, respectively (P = 0.88).

CONCLUSIONS

Although some AAs are less digestible in pea protein than in casein, the real ileal digestibility and the NPPU were not different. The DIAAS of 1.00 obtained for pea protein demonstrated its ability to meet all AA requirements. This study shows the potential of pea isolate as a high-quality protein. This study was registered at clinicaltrials.gov as NCT04072770.

Multi-criteria assessment of pea protein quality in rats: a comparison between casein, gluten and pea protein alone or supplemented with methionine

The objective of this study was to assess the nutritional quality of pea protein isolate in rats and to evaluate the impact of methionine (Met) supplementation. Several protein diets were studied: pea protein, casein, gluten, pea protein-gluten combination and pea protein supplemented with Met. Study 1: Young male Wistar rats (n 8/group) were fed the test diets ad libitum for 28 d. The protein efficiency ratio (PER) was measured. Study 2: Adult male Wistar rats (n 9/group) were fed the test diets for 10 d. A protein-free diet group was used to determine endogenous losses of N. The rats were placed in metabolism cages for 3 d to assess N balance, true faecal N digestibility and to calculate the Protein Digestible-Corrected Amino Acid Score (PDCAAS). They were then given a calibrated meal and euthanised 6 h later for collection of digestive contents. The true caecal amino acid (AA) digestibility was determined, and the Digestible Indispensable Amino Acid Score (DIAAS) was calculated. Met supplementation increased the PER of pea protein (2·52 v. 1·14, P < 0·001) up to the PER of casein (2·55). Mean true caecal AA digestibility was 94 % for pea protein. The DIAAS was 0·88 for pea protein and 1·10 with Met supplementation, 1·29 for casein and 0·25 for gluten. Pea protein was highly digestible in rats under our experimental conditions, and Met supplementation enabled generation of a mixture that had a protein quality that was not different from that of casein.

Effects of Whey and Pea Protein Supplementation on Post-Eccentric Exercise Muscle Damage: A Randomized Trial

This randomized trial compared pea protein, whey protein, and water-only supplementation on muscle damage, inflammation, delayed onset of muscle soreness (DOMS), and physical fitness test performance during a 5-day period after a 90-min eccentric exercise bout in non-athletic non-obese males (n = 92, ages 18–55 years). The two protein sources (0.9 g protein/kg divided into three doses/day) were administered under double blind procedures. The eccentric exercise protocol induced significant muscle damage and soreness, and reduced bench press and 30-s Wingate performance. Whey protein supplementation significantly attenuated post-exercise blood levels for biomarkers of muscle damage compared to water-only, with large effect sizes for creatine kinase and myoglobin during the fourth and fifth days of recovery (Cohen’s d > 0.80); pea protein versus water supplementation had an intermediate non-significant effect (Cohen’s d < 0.50); and no significant differences between whey and pea protein were found. Whey and pea protein compared to water supplementation had no significant effects on post-exercise DOMS and the fitness tests. In conclusion, high intake of whey protein for 5 days after intensive eccentric exercise mitigated the efflux of muscle damage biomarkers, with the intake of pea protein having an intermediate effect.

Real Ileal Digestibility of Pea Protein Compared to Casein in Healthy Humans

Objectives

The global demand for protein is growing and it seems mandatory to find alternatives to animal proteins that are of good nutritional quality, implying a good digestibility. Legumes are potential candidates, as their indispensable amino acid (IAA) profile is relatively balanced. The aim of this study is to compare the protein and AA ileal digestibility of pea protein and casein in humans using ileal sampling and intrinsically labelled proteins.

Methods

Sixteen healthy volunteers were intubated and were given twelve doses of mashed potatoes containing either pea protein or milk casein isolates. The proteins were intrinsically labelled with 15N. Polyethylene glycol (PEG) was perfused as a non-absorbable marker to measure the intestinal flow, and ileal digesta were collected during 8 hours after the ingestion of the first meal. PEG content was assessed using a turbidimetric assay. Real ileal nitrogen (N) digestibility was measured by assessing N content and 15N enrichment by EA-IRMS and calculated as follows: $$\begin{eqnarray} \begin{array} \text{Ileal fiow (mL/30 min)} &=& \rm{[PEG]_{solution}/[PEG]_{digesta}}\\ &&\times \text{ infusion rate} \times \rm{time} \end{array} \end{eqnarray}$$$$\begin{eqnarray} \begin{array} \text{Exogenous N fiow (mmol/30 min) } &=& \rm {N_{exo} = (\% DM \times \%N)}\\ &&/(14 \times 10) \times \text{ileal fiow} \times \rm{APE_{digesta}/APE_{meal}} \end{array} \end{eqnarray}$$$$\begin{eqnarray} \rm{Digestibility\ (\%)} = (\rm{N_{ingested} - N_{exo} / N_{ingested} \times 100}) \end{eqnarray}$$$$\begin{eqnarray} \text{WithDM = DryMatterofdigesta, APE = AtomPercentExcess} \end{eqnarray}$$

Results

The first results were obtained on 7 subjects that were given pea protein (N = 3) or milk casein (N = 4). The mean ileal flow for all the volunteers was 1.83 ± 0.70 mL/30 min (mean ± SD), and was quite stable over time. The total N exogenous flow was 15.50 ± 5.83 mmol for pea protein and 13.56 ± 3.48 mmol for casein. The true ileal N digestibility was 95.40 ± 1.73% for pea protein and 95.42 ± 1.17% for casein. Ileal IAA digestibility is in progress.

Conclusions

The intermediate results show no difference between pea protein and casein in terms of ileal digestibility, suggesting that pea protein could be a promising plant-based alternative. AA digestibilities and data from the remaining 9 volunteers to be tested will complete the study.

Funding Sources

Roquette.

Nutritional Quality Evaluation of a Pea Protein Isolate in Rats with or Without Amino Acid Supplementation (P08-064-19)

Objectives

The global demand for protein is growing and it seems necessary to find new alternatives for animal proteins. Legumes are good candidates, as their indispensable amino acid (IAA) profile is relatively balanced. The aim of the study is to evaluate the nutritional quality of a pea protein isolate (NUTRALYS® pea protein), with or without methionine (Met) supplementation, using various indexes. We measured the Protein Efficiency Ratio (PER), the Digestible Indispensable Amino Acid Score (DIAAS) and the nitrogen balance in rats.

Methods

Study 1: 40 Wistar male rats weighing ∼50 g were fed ad libitum for 28 days with a diet containing 10% protein with variation in protein sources only. 5 groups (n = 8) were included: pea, casein, wheat gluten, pea-gluten combination, pea supplemented with Met. PER is obtained by the ratio between weight gain and protein intake throughout the experimental period.

Study 2: 45 Wistar male rats weighing ∼250 g were housed in metabolic cages for 2 days and fed with a diet containing 14% protein of different sources. 5 groups (n = 9) were included: pea, casein, gluten, pea supplemented with Met, and protein-free diet for endogenous losses. Nitrogen content of diets, feces and urines was measured with an elementary analyzer for nitrogen balance (N ingested – N excreted). Then, rats were given a calibrated meal containing an indigestible marker and were euthanized 6 h later. Stomach, intestine, ileum, cecum, and colon contents were collected. DIAAS was calculated as follows: mg digestible IAA in 1 g of test protein*100/mg of IAA in 1 g of reference protein. IAA in ileum contents and diets were assayed by UPLC.

Results

Values are means ± SD.

Met supplementation allows pea protein to reach the PER of casein, but association with gluten is not sufficient. Nitrogen balance values are higher for casein and pea + Met. Fecal digestibility of pea protein is higher than casein in our conditions. Analysis for DIAAS calculation are ongoing.

Conclusions

Pea protein is highly digestible in our conditions and Met supplementation can improve its capacity to insure growth.

Funding Sources

Roquette.

A pilot investigation to optimise methods for a future satiety preload study

Background

Preload studies are used to investigate the satiating effects of foods and food ingredients. However, the design of preload studies is complex, with many methodological considerations influencing appetite responses. The aim of this pilot investigation was to determine acceptability, and optimise methods, for a future satiety preload study. Specifically, we investigated the effects of altering (i) energy intake at a standardised breakfast (gender-specific or non-gender specific), and (ii) the duration between mid-morning preload and ad libitum lunch meal, on morning appetite scores and energy intake at lunch.

Methods

Participants attended a single study visit. Female participants consumed a 214-kcal breakfast (n = 10) or 266-kcal breakfast (n = 10), equivalent to 10% of recommended daily energy intakes for females and males, respectively. Male participants (n = 20) consumed a 266-kcal breakfast. All participants received a 250-ml orange juice preload 2 h after breakfast. The impact of different study timings was evaluated in male participants, with 10 males following one protocol (protocol 1) and 10 males following another (protocol 2). The duration between preload and ad libitum lunch meal was 2 h (protocol 1) or 2.5 h (protocol 2), with the ad libitum lunch meal provided at 12.00 or 13.00, respectively. All female participants followed protocol 2. Visual analogue scale (VAS) questionnaires were used to assess appetite responses and food/drink palatability.

Results

Correlation between male and female appetite scores was higher with the provision of a gender-specific breakfast, compared to non-gender-specific breakfast (Pearson correlation of 0.747 and 0.479, respectively). No differences in subjective appetite or ad libitum energy intake were found between protocols 1 and 2. VAS mean ratings of liking, enjoyment, and palatability were all > 66 out of 100 mm for breakfast, preload, and lunch meals.

Conclusions

The findings of this pilot study confirm the acceptability of this methodology for future satiety preload studies. Appetite scores increased from preload to ad libitum lunch meal; however, no specific differences were found between protocols. The results highlight the importance of considering energy intake prior to preload provision, with a gender-specific breakfast improving the correlation between male and female appetite score responses to a morning preload.

Benefits of Preventive Administration of Chlorella sp. on Visceral Pain and Cystitis Induced by a Single Administration of Cyclophosphamide in Female Wistar Rat

Chlorella sp. is a green microalgae containing nutrients, vitamins, minerals, and chlorophyll. In some communities, Chlorella sp. is a traditional medicinal plant used for the management of inflammation-related diseases. In a rat model, ROQUETTE Chlorella sp. (RCs) benefits were investigated on visceral pain and associated inflammatory parameters related to cystitis both induced by cyclophosphamide (CYP). RCs was orally administered every day from day 1-16 (250 and 500 mg/kg body weight). Six hours after an intraperitoneal injection of 200 mg/kg body weight of CYP, body temperature, general behavior, food intake, and body weight were recorded. Twenty-four hours after CYP injection, rats were tested in two behavioral tests, an open field and the aversive light stimulus avoidance conditioning test, to evaluate the influence of pain on general activity and learning ability of rats. After euthanasia, bladders were weighed, their thickness was scored, and the urinary hemoglobin was measured. RCs orally administered at the two dosages significantly reduced visceral pain and associated inflammatory parameters related to cystitis both induced by CYP injection, and improved rat behavior. To conclude, RCs demonstrated beneficial effects against visceral pain and cystitis.

Evaluation of adherence by elderly nursing home patients to regular consumption of apple compote enriched with protein and soluble fiber

BACKGROUND

An increase in daily doses of protein and fiber for the elderly is relevant in preventing sarcopenia and preserving intestinal balance. However, such intake of supplements is often compromised by the lack of adherence among the elderly.

OBJECTIVES

The main objective was to evaluate the perception of the hedonic qualities of compote enriched with NUTRALYS(®) pea protein, NUTRALYS(®)W hydrolyzed wheat gluten and NUTRIOSE(®) soluble fiber and the changes in that perception due to repeated consumption. The secondary objectives were to evaluate the evolution in the quantity of compote eaten, satisfaction with consumption and any changes in fatigue, digestive comfort and digestive tolerance when eating compote every other day for 3 weeks.

METHOD

An observational study was conducted in nursing homes on volunteers aged 70-90 years. The compote was proposed as a lunchtime dessert every two days for a period of three consecutive weeks. All criteria were evaluated at days D0 and/or D1, D7, D15 and D21, except for the amount of compote eaten, evaluated after each meal at which it was served.

RESULTS

When first tasted, the compote was judged 'rather pleasant' to 'very pleasant' by 91.6 % and this rating held up at 79.2 % (p = 0.1797) after 1 week, 83.3 % (p = 0.3173) after 2 weeks and 79.2 % (p = 0.2568) after 3 weeks. Average consumption of compote was stable and varied between a maximum of 79.5 % of the total quantity at inclusion to a minimum of 61.5 % recorded on D17. The other parameters did not change significantly.

CONCLUSION

Pea protein, hydrolyzed wheat gluten and soluble fiber seem to provide an appropriate form of protein and fiber supplementation in the diets of elderly people in nursing homes.

NUTRALYS(®) pea protein: characterization of in vitro gastric digestion and in vivo gastrointestinal peptide responses relevant to satiety

BACKGROUND

Pea protein (from Pisum sativum) is under consideration as a sustainable, satiety-inducing food ingredient.

OBJECTIVE

In the current study, pea-protein-induced physiological signals relevant to satiety were characterized in vitro via gastric digestion kinetics and in vivo by monitoring post-meal gastrointestinal hormonal responses in rats.

DESIGN

Under in vitro simulated gastric conditions, the digestion of NUTRALYS(®) pea protein was compared to that of two dairy proteins, slow-digestible casein and fast-digestible whey. In vivo, blood glucose and gastrointestinal hormonal (insulin, ghrelin, cholecystokinin [CCK], glucagon-like peptide 1 [GLP-1], and peptide YY [PYY]) responses were monitored in nine male Wistar rats following isocaloric (11 kcal) meals containing 35 energy% of either NUTRALYS(®) pea protein, whey protein, or carbohydrate (non-protein).

RESULTS

In vitro, pea protein transiently aggregated into particles, whereas casein formed a more enduring protein network and whey protein remained dissolved. Pea-protein particle size ranged from 50 to 500 µm, well below the 2 mm threshold for gastric retention in humans. In vivo, pea-protein and whey-protein meals induced comparable responses for CCK, GLP-1, and PYY, that is, the anorexigenic hormones. Pea protein induced weaker initial, but equal 3-h integrated ghrelin and insulin responses than whey protein, possibly due to the slower gastric breakdown of pea protein observed in vitro. Two hours after meals, CCK levels were more elevated in the case of protein meals compared to that of non-protein meals.

CONCLUSIONS

These results indicate that 1) pea protein transiently aggregates in the stomach and has an intermediately fast intestinal bioavailability in between that of whey and casein; 2) pea-protein- and dairy-protein-containing meals were comparably efficacious in triggering gastrointestinal satiety signals.

Pea proteins oral supplementation promotes muscle thickness gains during resistance training: a double-blind, randomized, Placebo-controlled clinical trial vs. Whey protein

Background

The effects of protein supplementation on muscle thickness and strength seem largely dependent on its composition. The current study aimed at comparing the impact of an oral supplementation with vegetable Pea protein (NUTRALYS®) vs. Whey protein and Placebo on biceps brachii muscle thickness and strength after a 12-week resistance training program.

Methods

One hundred and sixty one males, aged 18 to 35 years were enrolled in the study and underwent 12 weeks of resistance training on upper limb muscles. According to randomization, they were included in the Pea protein (n = 53), Whey protein (n = 54) or Placebo (n = 54) group. All had to take 25 g of the proteins or placebo twice a day during the 12-week training period. Tests were performed on biceps muscles at inclusion (D0), mid (D42) and post training (D84). Muscle thickness was evaluated using ultrasonography, and strength was measured on an isokinetic dynamometer.

Results

Results showed a significant time effect for biceps brachii muscle thickness (P < 0.0001). Thickness increased from 24.9 ± 3.8 mm to 26.9 ± 4.1 mm and 27.3 ± 4.4 mm at D0, D42 and D84, respectively, with only a trend toward significant differences between groups (P = 0.09). Performing a sensitivity study on the weakest participants (with regards to strength at inclusion), thickness increases were significantly different between groups (+20.2 ± 12.3%, +15.6 ± 13.5% and +8.6 ± 7.3% for Pea, Whey and Placebo, respectively; P < 0.05). Increases in thickness were significantly greater in the Pea group as compared to Placebo whereas there was no difference between Whey and the two other conditions. Muscle strength also increased with time with no statistical difference between groups.

Conclusions

In addition to an appropriate training, the supplementation with pea protein promoted a greater increase of muscle thickness as compared to Placebo and especially for people starting or returning to a muscular strengthening. Since no difference was obtained between the two protein groups, vegetable pea proteins could be used as an alternative to Whey-based dietary products.

Trial registration

The present trial has been registered at ClinicalTrials.gov (NCT02128516).

In vitro fermentation of NUTRIOSE(®) FB06, a wheat dextrin soluble fibre, in a continuous culture human colonic model system

Wheat dextrin soluble fibre may have metabolic and health benefits, potentially acting via mechanisms governed by the selective modulation of the human gut microbiota. Our aim was to examine the impact of wheat dextrin on the composition and metabolic activity of the gut microbiota. We used a validated in vitro three-stage continuous culture human colonic model (gut model) system comprised of vessels simulating anatomical regions of the human colon. To mimic human ingestion, 7 g of wheat dextrin (NUTRIOSE^® FB06) was administered to three gut models, twice daily at 10.00 and 15.00, for a total of 18 days. Samples were collected and analysed for microbial composition and organic acid concentrations by 16S rRNA-based fluorescence in situ hybridisation and gas chromatography approaches, respectively. Wheat dextrin mediated a significant increase in total bacteria in vessels simulating the transverse and distal colon, and a significant increase in key butyrate-producing bacteria Clostridium cluster XIVa and Roseburia genus in all vessels of the gut model. The production of principal short-chain fatty acids, acetate, propionate and butyrate, which have been purported to have protective, trophic and metabolic host benefits, were increased. Specifically, wheat dextrin fermentation had a significant butyrogenic effect in all vessels of the gut model and significantly increased production of acetate (vessels 2 and 3) and propionate (vessel 3), simulating the transverse and distal regions of the human colon, respectively. In conclusion, wheat dextrin NUTRIOSE^® FB06 is selectively fermented in vitro by Clostridium cluster XIVa and Roseburia genus and beneficially alters the metabolic profile of the human gut microbiota.

Impact of a resistant dextrin on intestinal ecology: how altering the digestive ecosystem with NUTRIOSE®, a soluble fibre with prebiotic properties, may be beneficial for health

OBJECTIVES

The prebiotic potential of NUTRIOSE®--a sugar-free, digestion-resistant dextrin--was evaluated in two randomized, placebo-controlled trials that included 48 and 40 healthy volunteers, respectively.

METHODS

In study 1, the effect on colonic bacteria of NUTRIOSE® 10, 15 or 20 g/day administered for 14 days was examined; in study 2, gut microbial changes in response to NUTRIOSE® 8 g/day for 14 days were monitored using real-time polymerase chain reaction analysis.

RESULTS

NUTRIOSE® increased proliferation of Bacteroides and inhibited Clostridum perfringens in both studies, increased β-glucosidase activity (at 10 and 15 g/day) and decreased colonic pH (at 20 g/day). The increase in short-chain fatty acid production with NUTRIOSE® consumption was not statistically significant. There were no indications of gastrointestinal intolerance at any dose.

CONCLUSIONS

According to commonly accepted definitions, NUTRIOSE® is a prebiotic soluble fibre that provides a beneficial effect on colonic ecology while preserving digestive comfort.

The soluble fiber NUTRIOSE induces a dose-dependent beneficial impact on satiety over time in humans

Strong evidence supports the ability of dietary fibers to improve satiety. However, large variations in the physical and chemical characteristics of dietary fiber modulate the physiologic responses. We hypothesized that a nonviscous soluble dietary fiber may influence satiety. This randomized, double-blind, placebo-controlled clinical study in 100 overweight healthy adults in China investigated the effect of different dosages of dietary supplementation with a dextrin, NUTRIOSE (ROQUETTE frères, Lestrem, France), on short-term satiety over time. Subjects were randomized by body mass index and energy intake and then assigned to receive either placebo or 8, 14, 18, or 24 g/d of NUTRIOSE mixed with orange juice (n = 20 volunteers per group). On days -2, 0, 2, 5, 7, 14, and 21, short-term satiety was evaluated with a visual analog scale, and hunger feeling status was assessed with Likert scale. NUTRIOSE exhibits a progressive and significant impact on short-term satiety, which is time and dosage correlated. Some statistical differences appear for the group 8 g/d from day 5, and from day 0 for the groups 14, 18, and 24 g/d. The hunger feeling status decreases significantly from day 5 to the end of the evaluation for the group 24 g and from day 7 for the groups 14 and 18 g. By day 5, the group 24 g showed significantly longer time to hunger between meals compared with placebo. These results suggest that dietary supplementation with a soluble fiber can decrease hunger feeling and increase short-term satiety over time when added to a beverage from 8 to 24 g/d with time- and dose-responses relationship.

Impact of a resistant dextrin with a prolonged oxidation pattern on day-long ghrelin profile

OBJECTIVES

The effects of a new resistant dextrin ingested at breakfast on day-long metabolic parameters and ghrelin profile at subsequent lunch were investigated.

METHODS

In this randomized, single-blinded, crossover study, 12 healthy men ingested a standardized breakfast with 50 g of NUTRIOSE 10, a resistant dextrin (RD), or of maltodextrin (Malto) and a standardized lunch 5 hours later. Both products (RD and Malto) were derived from corn naturally rich in (13)C to follow their metabolic fate (by using stable isotope analysis). Oxidation and fermentation patterns were assessed by simultaneous (13)CO(2)/H(2) breath testing. The appearance of exogenous (13)C-glucose in plasma, glycemia, insulinemia, nonesterified fatty acids (NEFAs), and ghrelin concentrations were measured for 10 hours following breakfast ingestion.

RESULTS

With RD, H(2) excretion (fermentation) was significantly enhanced compared with Malto, whereas the appearance of (13)CO(2) (oxidation) was significantly prolonged (p < 0.0001). Following breakfast, ghrelin secretion was significantly less inhibited and NEFA concentration was higher with RD (p < 0.05), but unexpectedly, both remained lower after lunch and up to T600 minutes. According to the reduced bioavailability of RD compared with Malto, the appearance of (13)C-glucose in plasma (p < 0.0001) and glycemic and insulinemic responses to breakfast (p < 0.05) were significantly reduced.

CONCLUSIONS

Ingestion of this new resistant dextrin at breakfast decreased ghrelin concentrations in response to the subsequent lunch, even if the caloric load ingested at breakfast was lower. This effect may be linked to the prolonged fermentation/oxidation pattern seen in the late postprandial phase (up to 10 hours after ingestion at breakfast), and thus prolonged energy release with the resistant dextrin.

No observable differences in glycemic response to maltitol in human subjects from 3 ethnically diverse groups

Consumption of a low glycemic index (GI) diet may be helpful in the management and prevention of diabetes and cardiovascular disease. The investigation of GI has been predominantly confined to white subjects. We hypothesized that differences in glycemic response (GR) may be observable in subjects of different ethnic origin. The objective of the present study was to determine GR to a high GI (glucose) and low GI (maltitol) test drink in subjects of different ethnic origin. In a randomized, single-blind crossover trial, 10 whites, 10 South Indians and 10 Chinese subjects consumed either glucose or maltitol test drink containing 50 g of one of the test products on different occasions. Capillary blood glucose samples were taken at 15 and 10 minutes before and 0, 15, 30, 45, 60, 90, 120, 150, and 180 minutes after consumption of the test drink. The incremental area under the curve of glucose and maltitol were not significantly different between the 3 groups. The mean GR for maltitol was 33.5% in whites, 32.9% in Chinese, and 23.1% in South Indians. The results presented here confirmed that there are no observable differences noted in GR to a high-GI or low-GI test drink between the 3 ethnically diverse groups. We conclude that different ethnic groups exhibit similar GR to low- and high-GI drinks, and GR to maltitol is similar irrespective of ethnic background.