Geographical Provenance-Associated Differences in Lipophilic Phytochemical Fingerprints and Biological Activities of Peltophorum africanum from Two South African Collection Sites

Medicinal plants collected from different environments may yield chemically and biologically distinct preparations even when they share the same botanical identity. This study compared the lipophilic phytochemical profiles and in vitro antioxidant and antibacterial activities of Peltophorum africanum leaf material collected at one purposively selected site in Bushbuckridge, Mpumalanga (MP), and one in Mafarana Village, Limpopo (LP), South Africa. Hexane and dichloromethane (DCM) extracts were examined using qualitative and quantitative phytochemical assays, thin-layer chromatography (TLC), DPPH-TLC bioautography, three antioxidant assays and antibacterial screening. The four site-derived extracts showed different phytochemical and chromatographic patterns. The MP hexane extract had the lowest DPPH IC50 (0.19 mg/mL), whereas the LP DCM extract had the lowest hydrogen peroxide-scavenging IC50 (0.48 mg/mL). Ferric reducing power IC50 values were similar across the extracts (0.48–0.55 mg/mL). In broth microdilution, only the DCM extracts inhibited Enterococcus faecalis at the tested range (MIC = 0.50 mg/mL for both sites); all other extract-organism combinations had MIC values > 1.00 mg/mL. The findings demonstrate geographical provenance-associated variation between the two sampled localities and identify assay-specific candidates for further study. They do not, however, establish that either single site represents its entire province. Broader multi-site and multi-season sampling with compound-level characterisation would strengthen geographical generalisation and mechanistic interpretation.