New acid anhydride from <i>Phalaris canariensis</i> with antimicrobial activity assessed through <i>in vitro</i> and <i>in silico</i> approaches

In this study, a novel fatty acid anhydride, named phalarisin 1, was successfully isolated from the ethyl acetate extract of <i>Phalaris canariensis</i> growing in Tunisia. The structural characterisation of the compound was achieved through various spectroscopic techniques including FT-IR, 1D and 2D-NMR spectroscopy, as well as acidic hydrolysis analyses. Remarkably, phalarisin exhibited potent antimicrobial properties against a range of pathogens including <i>Micrococcus luteus</i>, <i>Bacillus subtilis</i>, <i>Fusarium oxysporum</i>, and <i>Fusarium phylophylum</i>, with minimum inhibitory concentrations (MICs) ranging from 31.25 to 62.5 μg/mL. To grasp the antimicrobial potential of compound 1, molecular docking studies were performed and they furnished evidence indicating its ability to bind to proteins in bacteria and fungi that are pivotal for drug resistance.