Phytochemical Profiling, Antioxidant, Anti-Inflammatory, Thrombolytic, Hemolytic Activity In Vitro and In Silico Potential of Portulacaria afra 

The use of complementary herbal medicines has recently increased in an attempt to find effective alternative therapies that reduce the adverse effects of chemical drugs. Portulacaria afra is a rich source of phytochemicals with high antioxidant activity, and thus may possess health benefits. This study used the latest developments in GC-MS coupling with molecular docking techniques to identify and quantify the phytoconstituents in P. afra tissue extracts. The results revealed that n-butanol P. afra (BUT-PA) dry extracts contained total phenolic and flavonoids contents of 21.69 ± 0.28 mgGAE/g and 196.58 ± 6.29 mgGAE/g, respectively. The significant potential of antioxidants was observed through CUPRIC, FRAP, and ABTS methods while the DPPH method showed a moderate antioxidants potential for P. afra. Enzymatic antioxidants, superoxide dismutase, peroxidase and catalase also showed a better response in the BUT-PA dry extracts. The thrombolytic activity of the BUT-PA extracts ranged from 0.4 ± 0.32 to 11.2 ± 0.05%. Similarly, hemolytic activity ranged from 5.76 ± 0.15 to 9.26 ± 0.15% using the standard (triton x) method. The BUTPA and CHPA showed moderate acetylcholinesterase and butrylcholinesterase inhibition, ranging from 40.78 ± 0.52 to 58.97 ± 0.33, compared to galantamine. The carrageenan induced hind-paw edema assay, while BUT-PA extracts showed anti-inflammatory properties in a dose-dependent manner. Furthermore, 20 compounds were identified in the BUTPA extracts by GC-MS. Molecular docking was performed to explore the synergistic effect of the GC-MS-identified compounds on COX-1 and COX-2 inhibition. A high binding affinity was observed for Stigmastan-3, 5-diene, Phthalic acid, 3. Alpha-Hydroxy-5, 16-androstenol. The computed binding energies of the compounds revealed that all the compounds have a synergistic effect, preventing inflammation. It was concluded that active phytochemicals were present in P. afra, with the potential for multiple pharmacological applications as a latent source of pharmaceutically important compounds. This should be further explored to isolate secondary metabolites that can be employed in the treatment of different diseases.