Before modern antibiotics, people used traditional plant medicines to treat infections, with tormentil root employed for centuries in Irish and European traditional medicine to address wounds, sore throats, diarrhea, and gum disease. Antimicrobial resistance is a growing global threat where bacteria evolve to survive drugs, making some infections difficult or impossible to treat, prompting researchers to search for new antimicrobial compounds, with plants being a promising source due to their evolved bioactive chemicals. A recent study investigated whether Irish bogland plants contain compounds to fight multi-drug resistant bacteria, testing extracts from over 70 plant species collected from Irish bogs against clinically relevant bacterial pathogens, including those causing severe pneumonia and urinary tract infections.
Antimicrobial susceptibility testing was used to see if extracts inhibited bacterial growth by exposing bacteria to plant extracts, with initial screening showing tormentil extracts were antimicrobial and limited biofilm formation, suggesting compounds with antimicrobial activity. The study explored whether plant extracts could work in combination with existing antibiotics, as some plant compounds enhance antibiotic efficacy, finding that low levels of the antibiotic colistin, combined with tormentil extract, enhanced the antibiotic's efficacy against bacteria, whereas low-level colistin alone was insufficient. However, the specific compounds in tormentil responsible for the antimicrobial activity remain unidentified, and it is unclear how effective tormentil extract is compared to standard antibiotics in clinical settings or what potential side effects or toxicity might arise from its use in humans.