Researchers at the University of Nottingham has been found a way to kill the modern-day superbug MRSA by a one thousand year old Anglo-Saxon remedy for eye infections which originates from a manuscript in the British Library.
Dr Christina Lee, an Anglo-Saxon expert from the School of English has enlisted the help of microbiologists from University’s Centre for Biomolecular Sciences to recreate a 10th century potion for eye infections from Bald’s Leechbook an Old English leatherbound volume in the British Library, to see if it really works as an antibacterial remedy. The Leechbook is widely thought of as one of the earliest known medical textbooks and contains Anglo-Saxon medical advice and recipes for medicines, salves and treatments.
Early results on the ‘potion’, tested in vitro at Nottingham and backed up by mouse model tests at a university in the United States, are, in the words of the US collaborator, “astonishing”. The solution has had remarkable effects on Methicillin-resistant Staphylococcus aureus (MRSA) which is one of the most antibiotic-resistant bugs costing modern health services billions.
The testing of the ancient remedy was the idea of Dr Christina Lee, Associate Professor in Viking Studies and member of the University’s Institute for Medieval Research. 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 (bile from a cow’s stomach). It describes a very specific method of making the topical solution including the use of a brass vessel to brew it in, a straining to purify it and an instruction to leave the mixture for nine days before use.
The scientists at Nottingham made four separate batches of the remedy using fresh ingredients each time, as well as a control treatment using the same quantity of distilled water and brass sheet to mimic the brewing container but without the vegetable compounds.
The remedy was tested on cultures of the commonly found and hard to treat bacteria, Staphylococcus aureus, in both synthetic wounds and in infected wounds in mice.
The team made artificial wound infections by growing bacteria in plugs of collagen and then exposed them to each of the individual ingredients, or the full recipe. None of the individual ingredients alone had any measurable effect, but when combined according to the recipe the Staphylococcus populations were almost totally obliterated: about one bacterial cell in a thousand survived.
The team then went on to see what happened if they diluted the eye salve – as it is hard to know just how much of the medicine bacteria would be exposed to when applied to a real infection. They found that when the medicine is too dilute to kill Staphylococcus aureus, it interfered with bacterial cell-cell communication (quorum sensing). This is a key finding, because bacteria have to talk to each other to switch on the genes that allow them to damage infected tissues. Many microbiologists think that blocking this behaviour could be an alternative way of treating infection
One of the researcher concludes that the rise of antibiotic resistance in pathogenic bacteria and the lack of new antimicrobials in the developmental pipeline are key challenges for human health. There is a pressing need to develop new strategies against pathogens because the cost of developing new antibiotics is high and eventual resistance is likely. This truly cross-disciplinary project explores a new approach to modern health care problems by testing whether medieval remedies contain ingredients which kill bacteria or interfere with their ability to cause infection.
