Bioactive Metabolites from Aerial Parts of Plantago indica L.: Structural Elucidation and Integrated In Vitro/In Vivo Assessment of Anti-Inflammatory and Wound-Healing Efficacy

The genus Plantago (Plantaginaceae) is widely distributed worldwide. The Plantago species are used in traditional medicine as wound healers, anti-inflammatory agents, antipyretics, and analgesics. This study aimed to investigate the phytochemical composition from the aerial parts of Plantago indica L. and to evaluate its biological activities. Isolation studies and in vitro investigations were conducted on an aqueous phase of 80% EtOH extract of Plantago indica. In addition, in vivo studies were carried out using the MeOH, 80% EtOH, and water extracts. Plantarenaloside (1), 3-oxo-α-ionol β-glucoside (2), martynoside (3), acteoside (4), feruloyl gardoside (5), and ursolic acid (6) were isolated from the extract. The structures of the compounds were elucidated using 1D- and 2D-NMR and ESI-MS analyses. The extract, fractions, and pure compounds were tested in vitro for cytotoxicity (MTT), anti-inflammatory activity (NO, IL-6, and TNF-α production), wound healing (scratch test), and antioxidant capacity (DPPH, ABTS, SO). Feruloyl gardoside (20.11–58.27%) significantly reduced NO levels at concentrations of 25–100 µM. It significantly reduced IL-6 levels (40.17%) at 100 µM. Additionally, the in vivo anti-inflammatory (acetic acid-induced vascular permeability) and wound healing (incision and excision models) effects of the extracts were investigated. The findings suggest that P. indica may be considered to be a potential therapeutic option for managing inflammation and for promoting wound healing.