Recent research has identified practical ways to protect and deliver oxygen-sensitive gut bacteria for a path toward safer, standardised microbial therapies that could reduce reliance on donor-based faecal microbiota transplants.
In her doctoral thesis, Berta Bosch explored how to better preserve and deliver beneficial gut bacteria, many of which are extremely sensitive to oxygen, for therapeutic use. These bacteria play a crucial role in human health but delivering them safely into the large intestine has been a major challenge.
Currently, faecal microbiota transplantation is used to treat Clostridioides difficile infection and is being studied for other conditions, such as inflammatory bowel disease, irritable bowel syndrome, and metabolic diseases. However, faecal microbiota transplantation currently relies on donor material, which can be hard to standardise. Researchers are now developing alternatives based on cultured bacterial strains, aiming for safer and more controlled therapies.
How to protect bacteria from oxygen?
The study tested new methods for handling and formulating these microbes. Results showed that anaerobic (oxygen-free) preparation helps protect gut bacteria during faecal microbiota transplantation. In a clinical trial, this approach was safe for Parkinson’s patients and changed their gut microbiota, though it did not improve symptoms clinically.
Another successful method was a double-coated tablet that delivered live anaerobic bacteria to the colon in lab simulations, preserving their anti-inflammatory properties. A 14-strain bacterial mix also showed promise in reversing antibiotic-related gut imbalances in an artificial gut model.
“Gut bacteria are essential for health, but many of the most beneficial species die quickly when exposed to oxygen”, explains Bosch. “Our work shows how to protect these microbes and deliver them in a way that could transform patient care.”
Why does this matter? Many diseases involve a loss of oxygen-sensitive gut bacteria. Restoring these microbes could help reestablish a healthy microbiome. The findings pave the way for more standardized, patient-friendly treatments, moving beyond donor-based transplants toward targeted microbial formulations.
As interest in microbiome-based therapies grows for conditions like infections, inflammation, and metabolic disorders, this research offers practical solutions for safer, scalable treatments. While more studies are needed, these advances bring us closer to reliable gut microbiome therapies.
“Microbiome research is moving from theory to practice”, Bosch adds. “We’re building the tools to expand the reach and impact of these treatments.”
Berta Bosch defended the doctoral dissertation "New formulations for microbiome-based therapies" in the Faculty of Pharmacy, University of Helsinki, on 12 December 2025 at 13:00. Professor Simone Guglielmetti, University of Milano-Bicocca, served as the opponent, and Leena Peltonen as the custos.
Contact
- Berta Bosch, berta.boschboada@helsinki.fi