Glyphaea brevis - In vitro antioxidant and in silico biological activity of major constituents and molecular docking analyses.

Previous studies have revealed that leaf extracts of Glyphaea brevis possess antioxidant activity but the bioactivity and mechanisms of action of its major constituents remain unknown. This study evaluated in vitro antioxidant and free radical scavenging activities of Glyphaea brevis twigs and leaves, and probable toxicity profile, pharmacological activities and mechanisms of action of major phytoconstituents in silico. Phytochemical screening detected saponins, tannins, steroids, anthraquinones, flavonoids, terpenoids and phenolics in the extracts. HPLC fingerprinting revealed major compounds as ferulic, catechuic and coumaric acids. Twig extract contained more flavanols compared to the leaf extract while the leaf extract had more flavonol content. Extract of the twigs demonstrated higher ORAC, TEAC and FRAP compared to the leaf extract. In silico analyses predicted low acute toxicity risk and pharmacological activities which are in agreement with traditional use of the plant in the management of diseases such as dyspepsia, ulcers, chest pains, diarrhea, dysentery and sleeping sickness. The molecular docking studies revealed that coumaric acid and ferulic acid have the best binding for all proteins tested. In summary, Glyphaea brevis twigs possess higher antioxidant activity than the leaves and major constituents showed low toxicological potential and promising biological activities which support its ethnomedical use.