Highly invasive alien plant Reynoutria japonica Houtt. represents a novel source for pharmaceutical industry - evidence from phenolic profile and biological activity

Reynoutria japonica is on the IUCN list of the Worlds’100 worst invasive species, but it is also, especially its rhizome, an integral part of traditional chinese medicine. The objective of this study was to determine the amount of selected phenolic compounds in rhizome, stems, leaves and inflorescence methanol extracts of this plant, their antioxidant and anticholinesterase activity. The chemical profile of the examined extracts was obtained by a high-performance liquid chromatography. In vitro assays on DPPH, OH and NO radicals were used to estimate antioxidant potential and Ellman’s method was applied for the determination of anticholinesterase activity. Leaves and rhizome extracts were found to be rich in rosmarinic and chlorogenic acid, and selected flavonoids. Resveratrol was exclusively present in rhizome and stems extracts. All the investigated extracts expressed certain antioxidant activity, where leaves extract was the most active. However, rhizome extract was the strongest inhibitor of acetylcholinesterase. These findings indicate that there is a possibility of R. japonica exploitation for the isolation of biologically active phenolic compounds used in pharmaceutical and food industry