Chemical profiling and evaluation of toxicological, antioxidant, anti-inflammatory, anti-nociceptive and tyrosinase inhibitory potential of Portulacaria afra using in-vitro, in-vivo and in-silico studies

Portulacaria afra Jacq (Portulacaceae) is a medicinal plant used traditionally in the treatment of pain and inflammation. This study aimed to evaluate the phytochemical composition, toxicity, antinociceptive, and enzyme inhibition potential of P. afra. The methanol extract (PAME) was prepared through maceration and fractionated with ethanol to ethanol fraction of P. afra (ETPA). Both PAME and ETPA were found to be rich in total phenolic (TPC) and total flavonoid contents (TFC). Similarly, PAME showed the highest antioxidant potential through ABTS 93.16 ± 0.05 mg TE /g of dry extract (D.E.) while ETPA showed maximum results (462 ± 1.44 mg TE/g) in the CUPRAC method. The RP-UHPLC-MS analysis of PAME showed tentative identification of 101 compounds in the positive mode and 14 compounds in the negative mode of ionization while GC–MS profiling gave a total of 15 compounds. The acute oral toxicity study of PAME revealed the safety and biocompatibility of the extract up to a dose of 5000 mg/kg orally in rats. In-vitro data revealed that varying concentrations of P. afra significantly (p