Comparative analysis of bioactive phenolic compounds from flower buds and leaves of M. officinalis var. biloba Rehder & Wilson

Magnolia officinalis var. biloba Rehder & Wilson, a perennial deciduous tree of the genus Magnolia, is endemic to southern China [ 1 ]. Continuing previous research [ 2 ], dried flower buds (MOBK) and leaves (MOBL) of M. officinalis var . biloba collected from the Botanical Garden in Powsin (Poland) were subjected to ultrasound-assisted extraction using 30, 50 and 70% ( V/V ) EtOH as extraction solvents. Herbal preparations were analysed using coupled chromatographic (RP-LC), spectroscopic (PDA) and mass spectrometric (QTOF/ESI-MS/MS) techniques. The LC/MS investigation showed different quantitative and qualitative profiles of the main phenolic compounds, including phenolic acids, phenylethanoids, flavonols, lignans and neolignans. Their total content, determined as gallic acid equivalent (GAE) in spectrophotometric (Vis) studies, increased significantly with the elution strength of the extraction solvent and was highest in extracts obtained with 70% EtOH (49.92 and 34.32 mg GAE/g of dry wt, for MOBK and MOBL, respectively). Interestingly, the antiradical capacity of the above-mentioned extracts, as assessed by the DPPH. assay, was strongly correlated with the total lignans and neolignans and phenolic acid content, which was about two (for lignans) and four times (for phenolic acids) higher in MOBL than MOBK. As a result, the former extract exhibited higher antiradical activity (IC 50 ~10.15 μg/mL) than the latter (IC 50 ~24.76 μg/mL). Our study showed a close relationship between the type of plant material and the content of particular phenolic compounds, especially phenylethanoids, which are synthesised mainly in flower buds, whereas higher amounts of phenolic acids, lignans and neolignans were found in leaf extracts. Differences in the distribution of individual phenolic components in plant organs may affect their biological properties. Publication History Article published online: 05 March 2026 © 2026. Thieme. All rights reserved. Georg Thieme Verlag KG Oswald-Hesse-Straße 50, 70469 Stuttgart, Germany