irilone and 2-2--4-4--tetrahydroxybenzophenone

Little is known about the pharmacological activities of Iris adriatica (Iridaceae), a plant endemic to Dalmatia (Croatia). We therefore performed a bioassay-guided fractionation including high-performance counter current chromatography (HPCCC) and antibacterial tests using Mycobacterium smegmatis mc2 155. One obtained fraction was found to be antimycobacterially active with a MIC of 64 mg L-1. Furthermore, fractions were tested for resistance modulatory effects using ethidium bromide as substrate. We were able to identify the pure isoflavonic compounds irigenin and irilone and a fraction containing mainly benzophenone 2,4,6-trihydroxy-4-methoxy-benzophenone, responsible for the resistance-modulatory activity of this plant.

Topics: Anti-Bacterial Agents; Benzophenones; Iris Plant; Isoflavones; Microbial Sensitivity Tests; Mycobacterium smegmatis; Phenols; Plant Extracts