Medieval Remedy From Bald's Leechbook Found to Kill MRSA

Posted on March 30, 2015

A medieval remedy from Bald's Leechbook has been found to kill MRSA. Researchers from the University of Nottingham tested the 1,000-year-old potion described in the Old English leather bound book and found it is effective at killing MRSA.

Dr. Christina Lee, Associate Professor in Viking Studies and member of the University's Institute for Medieval Research, came up with the idea to test the ancient recipe. Dr. Lee translated the recipe from a transcript of the original Old English manuscript in the British Library. The recipe calls for two species of Allium (garlic and onion or leek), wine and oxgall. Oxgall is bile from a cow's stomach. The recipe calls for a topical solution to be made by brewing it in a brass vessel and then straining it. The solution is then to be left nine days before use.

The researchers found the Bald's Leechbook eye salve kills up to 90% of MRSA bacteria in 'in vivo' wound biopsies from mouse models. The remedy was tested on cultures of Staphylococcus aureus in both synthetic wounds and in infected wounds in mice. The salve was also able to disrupt S. aureus biofilms.

University microbiologist Dr Freya Harrison says, "We thought that Bald's eyesalve might show a small amount of antibiotic activity, because each of the ingredients has been shown by other researchers to have some effect on bacteria in the lab – copper and bile salts can kill bacteria, and the garlic family of plants make chemicals that interfere with the bacteria's ability to damage infected tissues. But we were absolutely blown away by just how effective the combination of ingredients was. We tested it in difficult conditions too; we let our artificial 'infections' grow into dense, mature populations called 'biofilms', where the individual cells bunch together and make a sticky coating that makes it hard for antibiotics to reach them. But unlike many modern antibiotics, Bald's eye salve has the power to breach these defences."

Dr. Steve Diggle from the University of Nottingham says, "When we built this recipe in the lab I didn't really expect it to actually do anything. When we found that it could actually disrupt and kill cells in S. aureus biofilms, I was genuinely amazed. Biofilms are naturally antibiotic resistant and difficult to treat so this was a great result. The fact that it works on an organism that it was apparently designed to treat (an infection of a stye in the eye) suggests that people were doing carefully planned experiments long before the scientific method was developed."

BBC News notes that Dr. Lee says there are many other similar medieval books with treatments for what look like bacterial infections.

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