GC-MS characterization, in vitro bioactivities, in silico molecular docking and ADMET studies of phytoconstituents from Rytigynia umbellulata (Hiern) Robyns essential oils

Background: Rytigynia umbellulate (Hiern) Robyns is often deciduous and has many folklore uses, such as anti-malaria and anti-diabetic. This study investigated the essential oil constituents of Rytigynia umbellulate leaf and stem, along with their antioxidant and cytotoxic activities as well as investigating in-silico molecular docking and ADMET studies of phytoconstituents. Methods: The essential oils were extracted using hydrodistillation and gas chromatography-mass spectrometry (GC-MS) for identification and characterisation. In silico studies were performed using AutoDock Vina in the PyRx workspace. The antioxidant activity of the volatile oils was evaluated using the 2,2ꞌ–diphenyl–1–picrylhydrazyl radical (DPPH*) method, while the brine shrimp lethality test determined cytotoxic potential. Results: The GC-MS analyses revealed eleven and thirteen compounds in the leaves and stem essential oils of R. umbellulata, representing 98.5% and 95.1% of the total oil contents, with phytol (73.5%) and pentadecanal (55.1%) as the most abundant components, respectively. The essential oils showed significant antioxidant activity with a 69.03±0.004 percentage inhibition. The in silico studies supported the cytotoxicity potential of the essential oils with the highest binding affinity and attributed the strongest inhibitory activity to β-Gurjunene and Acorenone with respect to the reference standard, doxorubicin, for both the target proteins. Conclusion: Phytoconstituents of the leaf and stem essential oil of R. umbellulata might be linked to the free radical scavenging and cytotoxic potential observed in this study.