Dracaena arborea (DA) and Bridelia ferruginea (BF) are medicinal plants used in the treatment of various ailments such as diabetes, infertility, and sexual dysfunctions. The aim of this work was to characterize these plants chemically and investigate their antioxidant and cytotoxicity in vitro and in silico. The cytotoxicity was determined in PC3, NIH3T3 and BT474 cells, and through hemolysis using erythrocytes. Furthermore, selected compounds from DA and BF were docked against some oxidative stress (Keap1: Kelch-like ECH-associated protein 1 and GST: glutathione S-transferase) and cytotoxicity (PARP10: poly(ADP-ribose) polymerase family member 10 and p90 RSK: p90 ribosomal S6 kinases) proteins to predict the ligand-protein interaction. We found that the total phenolic and flavonoid content in BF was significantly (p < 0.001) higher than that of DA. 16 and 32 phytocompounds were identified in DA and BF, respectively. The 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid (ABTS+) free radical scavenging activity, and cupric and ferric reducing power of BF were significantly (p < 0.05–0.001) higher than those of DA. Moreover, the ability of BF to inhibit lipid peroxidation was higher than that of DA. DA dose-dependently decreased the viability of PC3, NIH3T3, and BT474 cells, while BF tended to feed the cells. Drug-Likeness and toxicity prediction of selected compounds found in DA and BF were within the acceptable standards, according to Lipinski's rule. The majority of compounds found in DA and BF exhibited a strong binding affinity with Keap1, GST, PARP10 and p90 RSK, which supports the in vitro results. For instance, Cis-cyclohexane-1,3-diamine from DA showed a binding affinity of -6.73 kcal/mol and interacted with Keap1 through five conventional hydrogen bonds, while Nrf2 (a Keap1 inhibitor) exhibited a binding affinity of -11.82 kcal/mol and interacted with Keap1 via two conventional hydrogen bonds. 1,3-propanediamine, n-methyl identified in BF exhibited a high stability with Keap1 (-5.95 kcal/mol) due to the presence of 6 conventional hydrogen bonds. Among the compounds identified in DA, the best stable ligand interacting with PARP10 was 2-deoxy-alpha-d-ribopyranose (-7.62 kcal/mol), as it was well-matched in the PARP10 pocket through five conventional hydrogen bonds. In parallel, among the compounds present in BF, 2-[(methylamino)methyl]cyclohexanol showed the best binding affinity with PARP10 (-9.80 kcal/mol), which was higher than that of veliparib (-8.26 kcal/mol), used as a reference inhibitor. In conclusion, BF has the possibility to be exploited in the prevention/treatment of oxidative stress-related diseases, while DA could be a potential anticancer agent. This could justify their ethnomedicinal uses.
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