Antioxidative role of palm grass rhizome ameliorates anxiety and depression in experimental rodents and computer-aided model

Palm grass (Curculigo recurvata) is an ethnomedicinally important herb reported to have significant medicinal values. The present study aimed to evaluate the antidepressant and anxiolytic activities of a methanol extract of C. recurvata rhizome (Me-RCR) through different approaches. The antidepressant and anxiolytic properties of Me-RCR were assessed by using elevated plus maze (EPM), hole-board (HBT), tail suspension (TST), and forced swimming (FST) tests in Swiss Albino mice. The in-depth antioxidative potential of Me-RCR was also evaluated through DPPH radical scavenging activity, ferric-reducing power capacity, total phenolic, flavonoid, flavonol, and antioxidant content analysis. Computational investigations were performed using computer-aided methods for screening the anxiolytic, antidepressant, and antioxidative activities of the selected lead molecules. Treatment with Me-RCR (200 and 400 mg/kg, b.w.) notably increased the number of open arm entries and the time spent in the EPM test. In the HBT, Me-RCR exhibited significant anxiolytic activity at a dose of 200 mg/kg, whereas similar activity was observed at 400 mg/kg in the EPM test. Me-RCR significantly decreased the immobility time in a dose-dependent manner in both TST and FST. The IC50 for DPPH and reducing power capacity assay were found to be 18.56 and 193 μg/mL, respectively. Promising outcomes were noted for the determination of total phenolics, flavonoids, flavonols, and antioxidant capacity. In the case of computer-aided studies, nyasicoside showed promising binding energy for antidepressant and anxiolytic activities, whereas isocurculigine demonstrated promising effects as an antioxidant. Overall, these findings suggest that Me-RCR could be a favourable therapeutic candidate for the treatment of mental and psychiatric disorders, as well as a good source of antioxidants.