Antibacterial activity of medicinal plants from The Physicians of Myddvai, a 14th century Welsh medical manuscript.
BACKGROUND
Antimicrobial drug resistance is a growing threat to global public health. Historical records and herbal texts relating to traditional Celtic medicine indicate an extensive pharmacopeia of plants for treating infections likely caused by microbes. However, a major barrier for successful integration of these remedies into mainstream practice is the current lack of accurate interpretation and scientific validation.


METHODS
We investigated the flora of the Isle of Arran, Scotland, via in situ targeted screening of 83 out of 138 plants identified in Meddygion Myddvai (a 14th century Welsh manuscript) to treat conditions related to microbial infections, and an additional 18 plants from modern ethnobotanical knowledge on the island (Scottish School of Herbal Medicine). In a follow-up proof-of-concept study, bioassay-guided fractionation was performed to identify bioactive constituents from two high scoring hits that inhibited Staphylococcus aureus (Gram-positive) and Escherichia coli (Gram-negative) bacterial growth.


RESULTS
67 historical plants (80.7%) and 14 modern plants (77.8%) were found to have detectable levels of antimicrobial activity when tested using Mobile Discovery kits, with human saliva as a source of bacteria for screening. Sabinene, a natural bicyclic monoterpene from juniper "berries" (Juniperus communis L.) and alliin, a natural sulfoxide from garlic cloves (Allium sativum L.), were isolated and confirmed as primary antibacterial leads.


CONCLUSIONS
Using historical medical sources such as those associated with traditional Celtic medicine to guide rigorous, evidence-based scientific investigation, provides additional leads for new and alternative bioactive molecules for combating bacterial diseases.
Plants for Human Health Institute, North Carolina State University, North Carolina Research Campus, 600 Laureate Way, Kannapolis, NC 28081, United States; Department of Plant and Microbial Biology, North Carolina State University, 100 Derieux Place, Raleigh, NC 27695, United States; Scottish School of Herbal Medicine, Isle of Arran, Scotland, UK.
Charles Stephen
CS
Wagner
Department of Plant and Microbial Biology, North Carolina State University, 100 Derieux Place, Raleigh, NC 27695, United States.
Jillian
J
De Gezelle
Scottish School of Herbal Medicine, Isle of Arran, Scotland, UK.
Maureen
M
Robertson
Scottish School of Herbal Medicine, Isle of Arran, Scotland, UK.
Keith
K
Robertson
Plants for Human Health Institute, North Carolina State University, North Carolina Research Campus, 600 Laureate Way, Kannapolis, NC 28081, United States.
Mickey
M
Wilson
Plants for Human Health Institute, North Carolina State University, North Carolina Research Campus, 600 Laureate Way, Kannapolis, NC 28081, United States; Department of Plant and Microbial Biology, North Carolina State University, 100 Derieux Place, Raleigh, NC 27695, United States; Department of Food, Bioprocessing, and Nutrition Sciences, North Carolina State University, 400 Dan Allen Drive, Raleigh, NC 27695, United States. Electronic address: komarnytsky@ncsu.edu.
Slavko
S
Komarnytsky
D000900:Anti-Bacterial Agents / Q000266:history* / Q000302:isolation & purification / Q000494:pharmacology; D001419:Bacteria / Q000187:drug effects; D001424:Bacterial Infections / Q000188:drug therapy / Q000266:history; D019448:Ethnobotany / Q000266:history; D020834:Ethnopharmacology / Q000266:history; D049691:History, Medieval; D006801:Humans; D008519:Medicine, Traditional / Q000266:history*; D008517:Phytotherapy / Q000266:history / Q000379:methods; D028321:Plant Preparations / Q000266:history* / Q000494:pharmacology; D010946:Plants, Medicinal / Q000737:chemistry*; D012606:Scotland
D000900:Anti-Bacterial Agents; D028321:Plant Preparations
Alliin PubChem CID: 87310; MF: C10H16; MF: C6H11NO3S; MW: 136.234 g/mol; MW: 177.221 g/mol; Sabinene PubChem CID: 18818; Traditional use; antibiotics; ethnobotany; medicinal plants; microbial infections