Scientists are beginning to appreciate the importance of the gut microbiome to health and disease, and administering microbes that can improve our health or prevent disease is the next logical step. However, bacteria are sensitive and need to be protected. MIT researchers have now developed a method to coat bacteria in such a way that they are protected from oxygen and other stress factors during processing and delivery to the intestine. This self-building protective coating can pave the way for further bacterial therapies.
The gut microbiome is increasingly recognized as important in a variety of diseases, and scientists are only just beginning to scratch the surface of its complexity. They have observed that certain microbes are more abundant in the intestines of healthy people, such as Bacteroides thetaiotaomicron, which is involved in the digestion of carbohydrates. The potential of such bacteria to be therapeutic when administered to patients is worth investigating.
However, a major challenge in using gut microbes as a supplement or treatment is their delicate nature. As a living organism, bacteria require careful handling. Many gut microbes are anaerobic, which means that oxygen in the air can harm them. Typical freeze drying techniques used to prepare microbes as stable formulations suitable for storage and administration can be destructive to bacterial cells.
To remedy this, the MIT team developed a protective coating for microbes that can protect them from oxygen and damage during processing. “We believe this coating could be used to protect pretty much any microbe of interest,” said Ariel Furst, a researcher involved in the study. “We believe that there are microbes that can help with a wide variety of diseases and that we can protect them for manufacturing and production.”
The MIT team mixed polyphenols (commonly found in plant foods) and iron, then added bacteria to the mixture. The iron / polyphenol mixture spontaneously formed a self-organized coating on the bacteria, which protects them during freeze-drying. Once the freeze-dried bacterial product has been added to the capsules, it is ready for ingestion. Once in the gut, the acidic environment causes the coating to break down and the bacteria inside to escape and begin to multiply.
Study in the Journal of the American Chemical Society: Protection of anaerobic microbes from processing stressors with the help of metal-phenolic networks
Conn Hastings received his PhD from the Royal College of Surgeons, Ireland, for his work in drug delivery, where he investigated the potential of injectable hydrogels to deliver cells, drugs and nanoparticles in the treatment of cancer and cardiovascular disease. After completing his PhD and a year as a postdoctoral fellow, Conn pursued a career in academic publishing before becoming a full-time scientific writer and editor, combining his experience in biomedical sciences with his passion for written communication.