Healthy adults, inulin/psyllium crossover trial

Background: Recent studies show that colonic gas after ingestion of inulin can be reduced by co-administering psyllium.</p><p>Objective: We aimed to determine if slowing delivery of inulin to the colon by administering it in divided doses would mimic the effect of psyllium.</p><p>Methods: Healthy adults (n=17) were randomised to a single-blind, 3-arm, crossover trial. All consumed 20g inulin(I) powder dissolved in 500mL water and mixed with either 1) 20g psyllium husk (PI) or 2) 20g Maltodextrin (placebo) (MI) consumed as a single dose, or 3) 62.5ml divided doses of inulin(DI) given every 45 minutes over 6 hours. Breath Hydrogen (BH2) was measured over 24 hours, and stool microbiota was analysed using shotgun metagenomics.</p><p>Results: [mean(SD)] DI and PI significantly reduced area under the curve (AUC) BH2 0-360 mins compared to MI, p<0.001. AUC(0-6h) being (6199.4+/-2889.2) after DI and (6855+/-5137) after PI, significantly less than MI (9970.6 +/- 3102.7). This was associated with a significant increase in BH2 for both DI and PI during the evening from 360-720 (p=0.014) and overnight 720-1320 (p=0.002). Furthermore, there was an additional significant increase overnight in BH2 for DI compared to psyllium, DI=30423+/-15406, PI= 5671+/-4711 p<0.001. Those failing to show a fall in BH2 AUC0-6h with psyllium showed greater release of arabinose during in vitro fermentation. Metagenomic analysis identified two species abundantly expressed in non-responders, Clostridium spp. AM22_11AC and Phocaeicola dorei which are also correlated with BH2 production for PI treatment. Dietary FODMAP intake correlated inversely with BH2 AUC0-24h on psyllium and correlated with stool microbiome.</p><p>Conclusion: Divided administration of inulin mimics the effect of psyllium by reducing initial BH2 0-360 mins. BH2 is influenced by habitual dietary FODMAP intake, most likely due to associated changes in microbiome. Psyllium acts by both delaying transit to the colon and reducing colonic fermentation however degradation of psyllium by colonic microbiota may limit its effectiveness.

Classified as human gut / stool shotgun DNA metagenome of adult by deterministic_prior with confidence 0.90. Assay shotgun_dna.

• host external_curation.infant_catalog · “infant triage reason_code age_adult_only”
• body site study.title · “Metagenomic sequencing of stool samples from healthy”
• body site study.description · “studies show that colonic gas after ingestion”
• life stage external_curation.infant_catalog · “infant triage reason_code age_adult_only”
• life stage study.title · “from healthy human volunteers from the EON”

15 runs over 15 samples · mean 3.40 Gbp per run (median 4.15 Gbp, total 50.97 Gbp; 15 runs with a base count) · layout PAIRED 15 · platform ILLUMINA 15 · models Illumina NovaSeq 6000 (15) · 87% of runs with a Sandpiper profile · first public 2025-05-28

Alhasani AT first · Modasia AA · Anodiyil M · Corsetti M · Aliyu AI · Crooks C · Marciani L · Reid J · Yakubov GE · Taylor M · Avery A · Harris H · Warren FJ · Spiller RC last

PRJNA1109584.csv.gz (1.4 KB) · parquet (71.7 KB) — all 15 samples, every field with route and confidence · PRJNA1109584_determinations.csv.gz (1.9 KB) — 150 evidence rows