Shining the spotlight on NMR metabolic profiling and bioactivities of different solvent extracts of Piliostigma thonningii

Abstract

Piliostigma thonningii (Fabaceae) is a versatile medicinal plant used as a traditional remedy, especially in African countries. In the present study, ethyl acetate, methanolic and water extracts of different parts of (fruits, leaves, stem barks) P. thonningii were evaluated for their bioactive contents, enzyme inhibitory, antioxidant and antimicrobial activities. Antioxidant potentials were also displayed in various methods like phosphomolybdenum assay (0.79–5.94 mmol TE/g), radical scavenging assays (DPPH: 20.39–471.28 mg TE/g; ABTS: 42.43–654.14 mg TE/g); reducing assays (CUPRAC: 102.98–1207.42 mg TE/g; FRAP: 45.30–656.25 mg TE/g) and metal chelating activity (2.55–22.32 mg EDTAE/g). In particular, the methanolic and water extracts showed better antioxidant potential. Except for a few, the extracts were also found to act as inhibitors of enzymes such as acetylcholinesterase (2.35–5.35 mg GALAE/g), butyrylcholinesterase (0.83–13.80 mg GALAE/g), tyrosinase (4.03–143.86 mg KAE/g), amylase (0.21–1.39 mmol ACAE/g) and glucosidase (3.52–7.13 mmol ACAE/g). Additionally, all the tested extracts possessed significant antibacterial (minimum inhibitory concentration (MIC) and minimum bactericidal concentration: 0.11–0.61 mg/ml) and antifungal (MIC and minimum fungicidal concentration: 0.04–0.61 mg/ml) effects. Indeed, the data garnered from the present study provides a bright scope for the advanced investigation on this particular plant possessing pharmacologically active traits.