Bioactive and antioxidant properties of ethanol extract, dichloromethane and butanol fractions of Gongronema latifolium leaf

Gongronema latifolium Benth. is a tropical medicinal plant of significant ethnomedicinal importance in West Africa. This study evaluated the bioactive and antioxidant properties of the ethanol extract, dichloromethane (DCM) and butanol fractions of G. latifolium leaf. Following maceration and fractionation by Vacuum Liquid Chromatography (VLC), samples were subjected to qualitative phytochemical screening, Gas Chromatography–Mass Spectrometry (GC-MS) analysis, and in vitro antioxidant evaluation comprising DPPH radical scavenging, ferric reducing antioxidant power (FRAP), total phenolic content (TPC), and total flavonoid content (TFC). Phytochemical screening confirmed alkaloids, flavonoids, saponins, tannins, and cardiac glycosides in the ethanol extract. GC-MS identified 83 compounds in the crude extract dominated by Undecane, 2,6-dimethyl- (7.79%), Tridecane (4.38%), and γ-Terpinene (4.02%); 53 compounds in the DCM fraction, with 14-Octadecenoic acid methyl ester (6.81%), γ-Terpinene (6.12%), and Phytane (3.23%) as major constituents; and 86 compounds in the butanol fraction. At 100 µg/mL, DPPH inhibition was 72% for both the crude extract and DCM fraction, and 23% for the butanol fraction, versus 92% for ascorbic acid. FRAP absorbance values at 100 µg/mL were 1.98, 2.01, and 2.06 for crude, DCM, and butanol fractions, respectively, approaching the ascorbic acid standard (2.08). TPC was highest in the crude extract (39.8 mgGAE/g), while TFC was highest in the DCM fraction (87.16 mgRE/g). These findings establish a rich phytochemical profile and significant antioxidant capacity in G. latifolium leaf, with the crude extract and DCM fraction showing the most promising activity, supporting further investigation as sources of bioactive pharmaceutical compounds.