Bald's Leechbook (or Medicinale Anglicum) is a medieval medical book held in the UK National Library. Presumably it was written in the 9th century and only exists in one copy. Scientists at the University of Warwick have found that the book's medical recipe is effective against five strains of bacteria that cause biofilm infections. This could be the key to finding new ways to combat antibiotic-resistant bacteria.
At first glance, Bald's Leechbook is nothing more than a relic from the history of medicine. Therefore, most of this Old English text is of interest only to antique dealers, but one of the recipes, called Bald's eyesalve, may have modern uses. As the medical world is constantly battling antibiotic-resistant bacteria, if it fails, society may return to a time when minor infections that are now easily treatable can kill.
One of the directions of this struggle is the tactics of "disarming" infections with biofilms. Biofilms are the mechanism by which bacteria are able to defend themselves against attack. Freely moving single bacteria are vulnerable to antibiotics, but when they clump together on surfaces, they form biofilms that are much more resistant. Plaque is a prime example, but there are many more dangerous biofilms that can infect implanted medical devices or cover skin ulcers. In the latter case, if the biofilm is resistant to antibiotics, doctors often have to resort to amputation to avoid a fatal blood infection.
Bald's Leechbook's signature eye ointment is a blend of onions, garlic, wine, and bile salts that the researchers found to be effective against a variety of bacteria. Scientists have been able to isolate a number of bacteria associated with combat, respiratory, skin infections, as well as infections of medical devices and surgical wounds, and diseases such as pharyngitis, tonsillitis, scarlet fever, rheumatism and post-streptococcal glomerulonephritis, which can be "defeated" with of this medicine.
According to the team, the antibacterial effect is not the individual ingredients, but their combination. Garlic is well known for its antibacterial properties, but it is not effective against biofilms, so other ingredients must play a role in this process.
“We have proven that this medieval remedy can kill a variety of problematic bacteria grown in both the planktonic phase and biofilm. Since the mixture did not do much harm to human cells and mice, we could potentially develop a safe and effective antibacterial agent. Most of the antibiotics we use today are derived from natural compounds, but our work emphasizes the need to study not only individual compounds, but also mixtures of natural products to treat biofilm infections,”the authors of the work said.