Strategy for tracking probiotic strains in multiple samples

Abstract

Probiotics are live microbial cultures, and their consumption or application in adequate amounts to food products is shown to have beneficial properties for the consumers health. These microorganisms are currently used as a strategy to preserve the balance of microbial communi-ties in humans and, since they are similar to the indigenous microorganisms naturally found in our microbiota, or perform identical functions, they are used to treat certain diseases. Consumption of products containing probiotic strains has shown great potential in the prevention of oral, respiratory, gastrointestinal, and skin diseases. Bacillus pumilus, Bacillus subtilis, Levilactobacillus brevis (formally known as Lactobacillus brevis) and Limosilactobacillus reuteri (formally known as Lactobacillus reuteri) are four species of bacteria commonly found in our body, with well-known probiotic strains. They can help to inhibit the growth of pathogenic microorganisms, such as bacteria, fungi, protozoa, and viruses, contribute to the prevention of cardiovascular and bone diseases and to the treatment of oral, skin and gastrointestinal tract pathologies, like periodontitis, eczema and inflammatory bowel disease, have anti-inflammatory and immunomodulatory properties, and be commercially interesting since they produce metabolites such as antibiotics, enzymes and antigens. Some strains of Bacillus used commercially as probiotics, offer advantages in both their vegetative and endospore forms, when compared to other Levilactobacillus and Limosilactobacillus strains. These advantages include the capacity to be stored for extended periods in their desiccated form and at room temperature, heat-resistance, and stability at multiple pH values, making them particularly adaptable to the extreme conditions of the gastric tract. In this project, we aim to develop a panel of specific primers capable of detecting unique strains of B. subtilis, B. pumilus, L. brevis and L. reuteri in biological samples.

Date of Award	12 Dec 2025
Original language	English
Awarding Institution	Universidade Católica Portuguesa
Supervisor	Ricardo Jorge Pinto Araújo (Supervisor)