Valorization of Ganoderma Species: Chemical Characterization and Antidepressant-Like Activity

The present study invoved chemical characterization and evaluation of antidepressant-like potential of wood-degrading Ganoderma species (G. applanatum, G. brownii, G. lucidum, and G. philippii) gathered from different trees of natural forests in Uttarakhand, India. Mushrooms dried fruiting bodies in powdered form were subjected to the evaluation of mycochemical constituents. Various extracts were prepared by successive Soxhlet extraction utilizing petroleum ether, chloroform, methanol, and distilled water as solvents. The antidepressant-like effects of all the extracts were examined by the Forced Swimming Test (FST) behavioral model in mice of Swiss albino strain. Among mycochemical constituents, phenols (3.28–6.30 mg/g) were the dominant components in all the mushroom samples with appropriate contents of alkaloids (1.83–3.67 mg/g), flavonoids (2.10–4.17 mg/g), saponins (1.75–3.82 mg/g) and steroids (1.83–5.93 mg/g). At a dose of 200 mg/kg, the methanol extract of G. lucidum evinced a significant decline in the duration of immobility in animals in comparison with the control (p < 0.05, p = 0.02). The bioactive extract was fractionated and the n-butanol fraction of the methanol extract manifested significant antidepressant-like effect at a dose of 100 mg/kg equivalent to the effect produced by the standard drug (imipramine, 20 mg/kg). The antidepressant-like activity is significantly correlated with the phenols and flavonoids quantified in methanol extracts and bioactive n-butanol fraction. The present study indicated that n-butanol fraction obtained from methanol extract of G. lucidum exerts an antidepressant-like effect on mice and has immense potential for the management of depression.