In a recent scientific research paper by
Girma A, Seo W, She RC (2019) titled 'Antibacterial activity of varying UMF-graded mānuka honeys' PLoS ONE 14(10): e0224495, the scientists
observed if UMF values correlated with the antibacterial activity of mānuka honey against a variety of pathogens purchased over the counter.
They discovered that Mānuka honey exhibited antimicrobial activity against a spectrum of organisms including those with multi-drug resistance, with more potent activity overall against gram-positive than gram-negative bacteria.
Follow link for more: https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0224495