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Encapsulated Probiotics & Gut Microbiota

A Physiological Study of a Fermented Yogurt Drink Containing Probiotics

Status
Not yet recruiting
Phases
Phase 1
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT07439978
Acronym
Probiotics
Enrollment
50
Registered
2026-02-27
Start date
2026-04-01
Completion date
2026-08-01
Last updated
2026-05-08

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Colonisation, Colonization, Asymptomatic

Keywords

Probiotic, Microbiota, Colonization, Dairy

Brief summary

The aim of this study is to determine whether encapsulation of probiotic bacteria using natural plant protein can enhance bacterial colonisation. Lactobacillus rhamnosus is an ideal strain for the intervention, as it has been shown to affect overall gut health, gut-brain axis, and brain function. Twenty-five participants aged 25 to 65 years will be recruited and assessed on four occasions to compare the blood and faecal effects of a 28-day ingestion of a yoghurt beverage with and without the probiotic strain of interest. The study window will be 70+/13 days. The current study will provide important information on the physiological function of probiotics in the small bowel. Understanding the underlying physiological effects of targeted probiotic delivery to the intestine and the impact on the microbiome is important for health outcomes.

Detailed description

The investigators plan to assess the gut microbiome and changes in probiotic diversity at the end of a course of a beverage containing encapsulated Lacticaseibacillus rhamnosus, compared to those at the end of a course of the same beverage without probiotics. This is a randomised, double-blinded, placebo-controlled crossover study. Twenty-five healthy men and women with a body mass index (BMI) between 18.5-31.9 kg/m2, aged 25-65 years, will be recruited and randomised to a commercial fermented (yoghurt) drink containing a) encapsulated probiotics consisting of Lacticaseibacillus rhamnosus, or b) a non-probiotic fermented (yoghurt) dairy drink (control). The number of participants includes a 10% drop-out rate. Each participant will be studied on four occasions in random order following a crossover design. Each will receive a 200 ml beverage containing yoghurt per day for 28 days, either a) fortified with 1 billion probiotics contained in pea protein capsules or b) the control beverage (same yoghurt without probiotic). Faecal samples will be collected on four occasions: at baseline, and at 28, 42 and 70 days after baseline. The current study will provide important information on the physiological function of probiotics in metabolic and inflammatory biochemical parameters, as well as in their capacity to colonise the gastrointestinal tract.

Interventions

Twenty-five participants will be studied on four occasions in random order and in a crossover design. Subjects will receive a daily dose of 200 ml on two different occasions for 28 days, a commercial dairy drink fortified with 1Billion probiotics in the pea protein capsules. Feacal samples will be collected on four occasions: at baseline, 28 days after baseline, 42 days and 70 days after baseline.

DIETARY_SUPPLEMENT200 ml yogurt drink

Twenty-five participants will be studied on four occasions in random order and in a crossover design. Subjects will receive a daily dose 200 ml on two different occasions for 28 days, a commercial dairy drink (no probiotics). Feacal samples will be collected on four occasions: at baseline, 28 days after baseline, 42 days and 70 days after baseline.

Sponsors

University College Dublin
Lead SponsorOTHER

Study design

Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
TREATMENT
Masking
SINGLE (Subject)

Intervention model description

Each subject will be studied on four occasions in random order and in a crossover design. Subjects will receive a daily dose 200 ml on two different occasions for 28 days, either a) in a commercial dairy drink fortified with 1Billion probiotics in pea protein capsules or b) a commercial dairy drink (no probiotics). Feacal samples will be collected on four occasions: at baseline, 28 days, 42 days and 70 days after baseline.

Eligibility

Sex/Gender
ALL
Age
25 Years to 65 Years
Healthy volunteers
Yes

Inclusion criteria

* Capacity to obtain and sign informed consent before any study-related procedure * BMI range 18.5-31.9 kg/m2 * Willing to abstain from regular consumption of probiotic supplements or food products containing probiotic bacteria (including fermented food and beverages). * Willing to abstain from regular consumption of supplements and medications known to alter gastrointestinal function or inflammatory status during the study.

Exclusion criteria

Participants who meet any of the following criteria will be excluded: * Smoking * Substance abuse * Pregnancy * Diagnosis of type 1 and/or type 2 diabetes * Current (or within the last 4 weeks prior to study start) use of probiotic supplementation. * Immobile (defined as the inability to participate in all study-related procedures) * History of complicated gastrointestinal surgery * Diagnosed with inflammatory bowel disease (IBD) * Current diagnosis of psychiatric disease/s or syndromes * Current diagnosis of neurodegenerative disease * Systemic use of antibiotics and/or steroid medication in the last 4 months prior to inclusion * Use of any non-steroidal anti-inflammatory drug (NSAID) more than 3 times a week for the last 2 months * Consumption of any NSAID within 7 days of study start * Any condition which could substantially interfere with intestinal barrier function (e.g. gluten sensitivity, lactose intolerance, celiac disease, IBS, IBD) or in any other way with the outcome of the study, as decided by the principal investigator's discretion * Regular smoking, use of snuff, nicotine, cannabidiol narcotics/supplements, or e-cigarette use * Drinking more than 9 standard cups of alcohol per week and/or more than 3 standard cups of alcohol per occasion * Regular use, for more than three times a week for the last 2 months and/or 7 days prior to inclusion, of medications which, according to the principal investigator, can have an anti-inflammatory effect or affect in any way the intestinal barrier function or have an impact on the study analysis (such as laxatives, anti-diarrheal, anti-cholinergic, etc.) * After being included in the study, starting any medication or treatment that could potentially influence the study participation and/or study analysis.

Design outcomes

Primary

MeasureTime frameDescription
Colonisation28 daysFaecal abundance of Lactobacillus rhamnosus after probiotic consumption measured through shotgun metagenomics -libraries with Illumina Nextera XT, sequenced 150 bp paired-end on NextSeq 2000. Negative + positive controls will be processed alongside study samples with around 15M paired reads/sample after quality controls.

Contacts

CONTACTWerd Al-Najim, PhD
werd.al-najim@ucd.ie+353 0864117842
CONTACTAhmed Al-Humadi, PhD
ahmed.al-humadi@ucd.ie+353 083 0994008
PRINCIPAL_INVESTIGATORCarel Le Roux, PhD

St Vincent's University Hospital, Ireland

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: May 9, 2026