Integrated experimental and In silico evaluation of the antioxidant, antibacterial, antiviral, and antiproliferative activities of Boswellia neglecta S. Moore stem extract and its bioactive constituents.

Boswellia neglecta has been traditionally used to treat leukemia, cancer, and skin diseases. In this study, seven compounds (1-7) were isolated from the stem methanol extract and identified for the first time from this species using NMR spectroscopy. GC-MS analysis revealed 17 compounds, with olean-12-en-3-one (32.59 %), oleic acid (13.79 %), and β-amyrin (10.66 %) as major constituents. Among the isolated compounds 7 showed the strongest antibacterial activity against Pseudomonas aeruginosa (MIC = 0.23 ± 0.11 mg/mL). Compounds 3-7 demonstrated promising antioxidant activity (IC50 = 1.29-7.05 μg/mL) compared with ascorbic acid (IC50 = 0.86 μg/mL). The methanol extract also exhibited significant cytotoxicity against MCF-7 breast cancer cells (27.25 % viability at 200 μg/mL) and antiviral activity against influenza A (H1N1) (IC50 = 1.5 μg/mL, SI = 21). Molecular docking revealed that compound 7 had strong binding affinity against P. aeruginosa DNA gyrase (-10.8 kcal/mol), surpassing ciprofloxacin (-6.9 kcal/mol). Compounds 3-7 also had stronger affinities (-5.1 to -6.5 kcal/mol) against human peroxiredoxin 5 and (-6.0 to -10.3 kcal/mol) against myeloperoxidase compared to ascorbic acid (-4.7 and -6.0 kcal/mol). These findings highlight the plant's therapeutic potential, warranting further in vivo, preclinical, clinical, and mechanistic investigations.