Investigating the Impact of Humiome B2 (colon Delivered Riboflavin) and Riboflavin-overproducer Probiotic Strain Limosilactobacillus Reuteri AMBV339 on Intestinal and Vaginal Microbiome and Health of Healthy Adult Women (The VIAB2L Project)

The goal of this clinical trial is to learn if the probiotic strain Limosilactobacillus reuteri AMBV339 or colon-delivered riboflavin or their combination can change the gut and vaginal microbiome and metabolomics. It will also learn about the safety of the investigational product. The main questions it aims to answer are:

Do the probiotic strain Limosilactobacillus reuteri AMBV339 or colon-delivered riboflavin or their combination modify gut microbiome? Do the probiotic strain Limosilactobacillus reuteri AMBV339 or colon-delivered riboflavin or their combination modify gut microbiome?

Researchers will compare the probiotic strain Limosilactobacillus reuteri AMBV339 or colon-delivered riboflavin or their combination to a placebo (a look-alike substance that contains no drug) to see if they can change gut and vaginal microbiome. Intervention period is 28 days.

The goal of this clinical trial is to learn if the probiotic strain Limosilactobacillus reuteri AMBV339 or colon-delivered riboflavin or their combination can change the gut and vaginal microbiome and metabolomics. It will also learn about the safety of the investigational product. Participants are healthy adult females of reproductive age and will take the investigational products for 28 days. There will be several non-invasive measurements, including but not limited to gut microbiome measured in faecal samples and vaginal microbiome measured in vaginal samples. They will fill some questionnaires about their general health.

The investigational product is a probiotic strain (1 billion AFU), colon-delivered riboflavin,(10mg) and their combination.

Participants will:

Take the probiotic strain Limosilactobacillus reuteri AMBV339 or colon-delivered riboflavin or their combination or a placebo every day for 28 days.

Visit the clinic once every 2 weeks for checkups and tests. Keep a diary of their bowel habits and provide fecal and vaginal sample at visits.

Eligibility Criteria:
Inclusion Criteria:

* Women of reproductive age (appr. 18-45 years old)
* Women of self-reported good general health
* Living in Flanders and speaking Dutch
* Using a combination contraceptive pill (without stop week) during the study and preferably at least three months before the study OR having a hormonal intrauterine device during the study and preferably at least three months before the study
* Subjects willing and able to give written informed consent and to understand, to participate and to comply with the clinical study requirements.

Exclusion Criteria:

* Current pregnancy or breastfeeding
* Antibiotic/antimycotic use during the last three months before the study
* Use of group B vitamin supplements or vitamin C during the study (record vitamin use via questionnaires)
* Ketogenic diet during the study and during the last two weeks before the study
* Oral and vaginal probiotic, prebiotic, and postbiotic and synbiotic supplementation during the study or recent use during the last two weeks before the study
* Vaginal douching during the study
* Presence of general infection
* Having a reproductive disorder or current vaginal infection or vaginal symptoms (VVC, BV, AV, etc.)
* Having a gastro-intestinal disorder or current GIT infections or gastrointestinal disorders (Crohn, IBS, IBD, etc.)
* Having any other medical condition that gives rise to exclusion from the study according to the responsible clinician/principal investigator of the study
* Participation in another clinical trial