In Vitro and In Silico Assessment of <i>Datura stramonium</i> Flower Alkaloids as Multi‐Target Inhibitors of Biofilm Formation, Xanthine Oxidase, and Tyrosinase Enzymes

Drug repurposing and multi-target drug design are gaining importance as promising strategies for developing treatments for various diseases. In this study, three alkaloids, pyrrolezanthine 1, hyoscine 2, and atropine 3, were isolated from Datura stramonium flowers and evaluated for their inhibitory activities against bacterial biofilm formation, xanthine oxidase (XO), and tyrosinase enzymes using both in vitro and in silico studies. Compounds 1-3 displayed potent antibiofilm activities against multidrug-resistant Gram-positive and Gram-negative bacterial strains. Compounds 2 and 3 demonstrated significant XO inhibitory activity with IC₅₀ values of 11.76 ± 0.15 and 10.00 ± 0.12 µM, respectively, compared to the standard L-mimosine (IC₅₀ = 6.82 ± 0.06 µM). Additionally, these compounds showed enhanced tyrosinase inhibition (IC₅₀ = 21.79 ± 0.28 and 19.89 ± 0.24 µM, respectively) relative to kojic acid (IC₅₀ = 92.39 ± 0.55 µM). A molecular modeling simulation study supported the in vitro findings. Network pharmacology studies of compounds 2 and 3 identified the inflammatory targets and the potential mechanisms underlying their therapeutic effects. These results suggest that tropane alkaloids isolated from D. stramonium hold promising activities as multi-target drug candidates for treating gout, hyperpigmentation, and resistant bacterial infections.