ESI-LC-MS/MS based comparative multivariate metabolomic and biological profiling with dynamic molecular docking of...

A comprehensive study of leaves, flowers, fruits, bark, and seeds' extracts of Gmelina arborea Roxb was performed for first time to investigate their anti-inflammatory, anti-Alzheimer, and antidiabetic activities. A thorough comparative phytochemical investigation of the five organs was performed using Tandem ESI-LC-MS. The biological investigation, further aided by multivariate data analysis and molecular docking proved the highly significant potential of using G.arborea organs' extracts as medicinal agents. Chemometric analysis of the obtained data revealed 4 distinct clusters among different samples of the 5 G.arborea (GA)organs and also confirmed that each organ was chemically distinct from the others, except for fruits and seeds which were closely correlated. Compounds anticipated to be responsible for activity were identified by LC-MS/MS. To clarify the differential chemical biomarkers of G. arborea organs, an orthogonal partial least squares discriminant analysis (OPLS-DA) was constructed. Bark exhibited it's in vitro anti-inflammatory activity through down regulation of COX-1 pro-inflammatory markers while fruits and leaves affected mainly DPP4 the marker for diabetes, and flowers were the most potent against Alzheimer maker acetylcholine (ACE) esterase. The metabolomic profiling of the 5 extracts lead to the identification of 27 compounds in negative ion mode and the differences in chemical composition were correlated to difference in activity. Iridoid glycosides were the major class of identified compounds. Molecular docking proved the different affinities of our metabolite towards different targets. Gmelina arborea Roxb. is a very important plant both economically and medicinally.