Screening of phytocompounds, molecular docking studies, and in vivo anti-inflammatory activity of heartwood aqueous extract of Pterocarpus santalinus L.f.

Abstract

Objective: To evaluate the anti-inflammatory potential of aqueous extract of Pterocarpus santalinus L.f. heartwood using molecular docking and in vivo experiment. Methods: An aqueous extract of Pterocarpus santalinus heartwood was prepared using a Soxhlet apparatus. Phytocompounds in the extract were tentatively identified using high-resolution mass spectrometry. Molecular docking experiments were carried out to evaluate the binding affinity of selected compounds, phloridzin to cyclooxygenase-1 (COX-1), cyclooxygenase-2 (COX-2), prostaglandin E synthase-1 (PGES-1) and 5-lipoxygenase (5-LOX). Anti-inflammatory potential was evaluated by carageenan induced paw edema model in rats. Results: The presence of major component phloridzin along with quercetin, parthenin, ginkgolide B, picrotoxinin, usnic acid, octopine, and epigallocatechin was detected in the extract. Molecular docking study showed that phloridzin inhibited COX-1, COX-2, PGES-1 and 5-LOX with more affinity than ibuprofen and paracetamol. Pterocarpus santalinus heartwood extract at 200 and 400 mg/kg BW showed significant reduction in carageenan-induced hind paw edema in a dose-dependent manner, but the effect was slow when compared with the standard ibuprofen (30 mg/kg p.o.). Conclusions: The study indicated that after clinical trials, the aqueous extract of Pterocarpus santalinus heartwood can be effectively used in phytotherapy to treat inflammation.