Healthy VolunteersPROTEBOOST_1NCT07613983
Evaluation of the Bioavailability of Amino Acids From Purple Bacteria
A study testing Purple Bacteria-Enriched Dairy Product and Protein-Enriched Dairy Product in people with Healthy Volunteers, run by Université Catholique de Louvain at 1 site in Belgium.
Trial summary
This interventional clinical study aims to evaluate the bioavailability of amino acids derived from purple bacteria in healthy adults. Participants will consume either a protein-enriched dairy product or a protein-enriched dairy product containing purple bacteria during two separate test periods in a randomized… Read more about this study
- Who is it for?
- Ages 18 to 50 yearsHealthy volunteers can take part
- Conditions the study is for
- Healthy Volunteers
- What is being tested?
- Purple Bacteria-Enriched Dairy Product and Protein-Enriched Dairy Product
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 12 participants
- Where
- 1 siteBelgium
- Study dates
- 13 Apr 2026to 8 May 2026
- Phase
- Interventional
- Are there results?
- None posted in the registry
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 to 50 years
- All sexes
- Healthy volunteers accepted
- Adult
Who may be able to join
- Adults aged 18 to 50 years
- Body mass index between 18 and 30 kg/m²
- Healthy participants
- Non-smokers
- Women of childbearing potential using effective contraception
- Able to understand and speak French
- Willing and able to comply with study procedures
Who cannot join
- Pregnancy or breastfeeding
- Use of medications or dietary supplements incompatible with study participation
- Any medical condition considered by the investigator to interfere with study participation or interpretation of results
- Vegan or vegetarian diets
Trial locations and contacts
1 site in 1 country.
Belgium1 site
Center of Investigation in Clinical Nutrition (CICN)
Louvain-la-Neuve, 1348
About this study
Official title: Evaluation of the Consumption of Fresh Purple Bacteria Biomass in Healthy Humans: Safety Test and Monitoring of Metabolism
This interventional clinical study aims to evaluate the bioavailability of amino acids derived from purple bacteria in healthy adults. Participants will consume either a protein-enriched dairy product or a protein-enriched dairy product containing purple bacteria during two separate test periods in a randomized cross-over design. Blood amino acid concentrations will be measured over a 4-hour postprandial period to assess amino acid absorption and bioavailability.
Additional biological samples including saliva, exhaled air, and feces will be collected to evaluate gastrointestinal hormones, volatilome profiles, and related metabolic responses.
Read the detailed description
Purple bacteria are recognized for their high-quality protein content, including essential amino acids, as well as their vitamin and carotenoid composition. However, limited data are available regarding the bioavailability of amino acids derived from purple bacteria in humans.
This randomized, open-label, cross-over study will enroll approximately 12 healthy adult participants in Belgium. Each participant will receive two dairy-based formulations in randomized order:
Control formulation: protein-enriched dairy product. Test formulation: protein-enriched dairy product containing purple bacteria.
The two intervention periods will be separated by a washout period of at least one week.
Participants will undergo one screening visit and two test visits. During each test visit, serial blood samples will be collected over 240 minutes following ingestion of the assigned formulation to determine plasma amino acid concentrations. Additional saliva, exhaled air, and fecal samples will also be collected.
The primary objective is to determine whether amino acids present in purple bacteria are better absorbed than amino acids from other protein sources.
- Conditions
- Healthy Volunteers
- Being tested
- Purple Bacteria-Enriched Dairy Product, Protein-Enriched Dairy Product
- Keywords
- Purple bacteria, Amino acid bioavailability, Protein absorption, Functional foods, Postprandial metabolism, Dairy product, Healthy adults
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Purple Bacteria-Enriched Dairy ProductDietary supplement
Approximately 50 g of purple bacteria incorporated into approximately 110 g of a protein-enriched dairy product.
Protein-Enriched Dairy ProductOther
160 g of protein-enriched dairy product.
| Study group | Role | What they receive |
|---|---|---|
| Purple Bacteria Formulation | Experimental | Participants will consume a protein-enriched dairy product containing purple bacteria. Receives: Dietary Supplement: Purple Bacteria-Enriched Dairy Product |
| Control Formulation | Active comparator | Participants will consume a protein-enriched dairy product without purple bacteria. Receives: Other: Protein-Enriched Dairy Product |
What is being measured
The primary outcome is the main question the study is designed to answer.
Change in postprandial plasma essential amino acid concentrations (µmol/L)
Plasma concentrations of essential amino acids (including leucine, isoleucine, valine, lysine, threonine, phenylalanine, methionine, tryptophan, and histidine) will be measured using LC-MS/MS at baseline and at multiple postprandial time points following ingestion of control and test formulations. Results will be reported as incremental area under the curve (iAUC, µmol/L·h) over the postprandial period.
Measured: Throughout the entire study, approxiamtely during 1 month
Secondary outcomes (4)
Change in exhaled volatile organic compounds (VOCs) profile (relative abundance, arbitrary units)
Exhaled air samples will be analyzed using gas chromatography-mass spectrometry (GC-MS). Specific VOCs will be quantified and reported as relative abundance (arbitrary units) and/or multivariate profile changes (e.g., PCA scores) comparing test vs control formulations.
Measured: Throughout the entire study, approxiamtely during 1 month
Change in salivary gastrointestinal hormone concentrations (pg/mL)
Salivary concentrations of gastrointestinal hormones (e.g., ghrelin, GLP-1, PYY) will be measured using immunoassays. Results will be expressed as change from baseline and iAUC (pg/mL·h) over the postprandial period.
Measured: Throughout the entire study, approxiamtely during 1 month
Gastrointestinal symptom severity score assessed using a 5-point Likert scale (0-4)
Gastrointestinal tolerance will be assessed using a standardized symptom questionnaire evaluating the severity of gastrointestinal symptoms (including bloating, abdominal pain, flatulence, nausea, and diarrhea).
Each symptom will be rated using a 5-point Likert scale, defined as:
0 = not at all
- = slightly
- = moderately
- = severely
- = very severely
Results will be reported as:
mean gastrointestinal symptom score (average across symptoms) and/or total symptom score (sum of all items; higher scores indicate worse symptoms) and change from baseline over the postprandial period following ingestion of study formulations.
Measured: Throughout the entire study, approxiamtely during 1 month
Number of participants with at least one adverse event
Adverse events will be collected throughout the study period and reported as the number and proportion of participants experiencing at least one adverse event, by condition.
Measured: Throughout the entire study, approxiamtely during 1 month
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted29 May 2026
- Study start13 Apr 2026
- Primary completion8 May 2026
- Study completion8 May 2026
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Healthy VolunteersStudies of the same condition, open and under way.
- More trials run by Université Catholique de LouvainThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Basic science
- Allocation
- Randomised
- Intervention model
- Crossover
- Model description
- Participants will receive both study formulations in randomized order over two intervention periods separated by a washout period of at least one week.
- Masking
- Single blind
- Who is masked
- Participant
- Enrolment
- 12 participants (actual)
Sponsor and investigators
- Lead sponsor
- Université Catholique de Louvain
- Sponsor type
- University, hospital or other
- Collaborators
- University of Mons, University of Liege
- Responsible party
- Sponsor
- Investigators
- Sylvie Copine, Dr, Principal investigator, Université Catholique de LouvainLaurent Simar, Dr, Principal investigator, Université Catholique de Louvain
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07613983
- Sponsor's protocol ID
- PROTEBOOST_BIODISPO1
- Acronym
- PROTEBOOST_1
- Status last verified
- May 2026
- First submitted
- 4 May 2026
- Last updated
- 29 May 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No
Study at a glance
From the registry record, last updated by the sponsor on 29 May 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Evaluation of the Consumption of Fresh Purple Bacteria Biomass in Healthy Humans: Safety Test and Monitoring of Metabolism
- ClinicalTrials.gov ID
- NCT07613983
- Acronym / sponsor ID
- PROTEBOOST_1 / PROTEBOOST_BIODISPO1
- Conditions
- Healthy Volunteers
- Keywords
- Purple bacteria, Amino acid bioavailability, Protein absorption, Functional foods, Postprandial metabolism, Dairy product, Healthy adults
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 12 participants (actual)
- Lead sponsor
- Université Catholique de LouvainUniversity, hospital or other
- Collaborators
- University of Mons, University of Liege
- Study start
- 13 Apr 2026 (actual)
- Primary completion
- 8 May 2026 (actual)
- Study completion
- 8 May 2026 (actual)
- First posted
- 29 May 2026 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
This interventional clinical study aims to evaluate the bioavailability of amino acids derived from purple bacteria in healthy adults. Participants will consume either a protein-enriched dairy product or a protein-enriched dairy product containing purple bacteria during two separate test periods in a randomized cross-over design. Blood amino acid concentrations will be measured over a 4-hour postprandial period to assess amino acid absorption and bioavailability.
Additional biological samples including saliva, exhaled air, and feces will be collected to evaluate gastrointestinal hormones, volatilome profiles, and related metabolic responses.
Detailed description
Purple bacteria are recognized for their high-quality protein content, including essential amino acids, as well as their vitamin and carotenoid composition. However, limited data are available regarding the bioavailability of amino acids derived from purple bacteria in humans.
This randomized, open-label, cross-over study will enroll approximately 12 healthy adult participants in Belgium. Each participant will receive two dairy-based formulations in randomized order:
Control formulation: protein-enriched dairy product. Test formulation: protein-enriched dairy product containing purple bacteria.
The two intervention periods will be separated by a washout period of at least one week.
Participants will undergo one screening visit and two test visits. During each test visit, serial blood samples will be collected over 240 minutes following ingestion of the assigned formulation to determine plasma amino acid concentrations. Additional saliva, exhaled air, and fecal samples will also be collected.
The primary objective is to determine whether amino acids present in purple bacteria are better absorbed than amino acids from other protein sources.
Study design
- Primary purpose
- Basic science
- Allocation
- Randomised
- Intervention model
- Crossover
- Masking
- Single blind (participant)
- Number of arms
- 2
- Model description
- Participants will receive both study formulations in randomized order over two intervention periods separated by a washout period of at least one week.
| Arm | Type | Receives |
|---|---|---|
| Purple Bacteria Formulation | Experimental | Dietary Supplement: Purple Bacteria-Enriched Dairy ProductParticipants will consume a protein-enriched dairy product containing purple bacteria. |
| Control Formulation | Active comparator | Other: Protein-Enriched Dairy ProductParticipants will consume a protein-enriched dairy product without purple bacteria. |
Who may qualify
- Ages
- 18 to 50 years
- Sex
- All
- Healthy volunteers
- Accepted
- Age groups
- Adult
Key inclusion criteria (7 listed)
- Adults aged 18 to 50 years
- Body mass index between 18 and 30 kg/m²
- Healthy participants
- Non-smokers
- Women of childbearing potential using effective contraception
Key exclusion criteria (4 listed)
- Pregnancy or breastfeeding
- Use of medications or dietary supplements incompatible with study participation
- Any medical condition considered by the investigator to interfere with study participation or interpretation of results
- Vegan or vegetarian diets
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Purple Bacteria-Enriched Dairy ProductApproximately 50 g of purple bacteria incorporated into approximately 110 g of a protein-enriched dairy product. | Dietary supplement | Purple Bacteria Formulation |
| Protein-Enriched Dairy Product160 g of protein-enriched dairy product. | Other | Control Formulation |
Primary outcome
Change in postprandial plasma essential amino acid concentrations (µmol/L)
Time frame: Throughout the entire study, approxiamtely during 1 month
Plasma concentrations of essential amino acids (including leucine, isoleucine, valine, lysine, threonine, phenylalanine, methionine, tryptophan, and histidine) will be measured using LC-MS/MS at baseline and at multiple postprandial time points following ingestion of control and test formulations. Results will be reported as incremental area under the curve (iAUC, µmol/L·h) over the postprandial period.
4 secondary outcomes
Change in exhaled volatile organic compounds (VOCs) profile (relative abundance, arbitrary units)
Time frame: Throughout the entire study, approxiamtely during 1 month
Change in salivary gastrointestinal hormone concentrations (pg/mL)
Time frame: Throughout the entire study, approxiamtely during 1 month
Gastrointestinal symptom severity score assessed using a 5-point Likert scale (0-4)
Time frame: Throughout the entire study, approxiamtely during 1 month
Number of participants with at least one adverse event
Time frame: Throughout the entire study, approxiamtely during 1 month
Results and safety
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 29 May 2026.
- Individual participant dataSharing planned: No
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Screening Protocol
Pain
Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
Sylvie Copine, Dr principal investigator
Université Catholique de Louvain
Laurent Simar, Dr principal investigator
Université Catholique de Louvain
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Purple Bacteria-Enriched Dairy Product and Protein-Enriched Dairy Product in people with Healthy Volunteers, run by Université Catholique de Louvain at 1 site in Belgium.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 7 inclusion and 4 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: finished, as of the sponsor's last update on 29 May 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in Belgium. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Change in postprandial plasma essential amino acid concentrations (µmol/L) (time frame: Throughout the entire study, approxiamtely during 1 month). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 29 May 2026.