Phytochemical profiling, antimicrobial, antibiofilm, and molecular docking of Farsetia aegyptia and Zilla spinosa from Saudi Arabia

Background Farsetia aegyptia and Zilla spinosa belonging to the Brassicaceae family, well-known for their biological and therapeutic activities. Objective To our knowledge, this is the first comprehensive study to explore the composition, antibacterial, anticandidal, antibiofilm activities using in vitro , and molecular docking analysis assays of F. aegyptia and Z. spinosa herb extracts collected from the Hail region of Saudi Arabia. Methods The antibacterial and anticandida effects of chloroform, ethanolic, and aqueous extracts from the aerial parts of F. aegyptia and Z. spinosa were determined by conventional assays. The compositions of extracts were determined by Gas Chromatography–Mass Spectrometry (GC–MS) and High-Resolution Liquid Chromatography–Mass Spectrometry (HR–LC–MS). Molecular docking simulations were carried out with the major identified compounds against penicillin-binding protein 4. Results The chloroform and ethanolic extracts of these plants exhibited substantial activities against Enterococcus faecalis ATCC 29212, and Listeria monocytogenes ATCC 19115, with minimum inhibitory concentration (MIC), minimal bactericidal concentration (MBC) levels varying between 625 and 2,500 μg/mL, and MBC/MIC was equal to 1. The chloroformic extract of F. aegyptia demonstrated the most significant anticandidal activity against Candida albicans ATCC 90028 and Candida krusei ATCC 6258, with MIC of 625 μg/mL. Interestingly, the chloroform extract of F. aegyptia demonstrated the most important antibiofilm activity against Staphylococcus aureus , with Minimum Biofilm Inhibition Concentration (MBIC50) of 700 μg/mL, while the chloroform extract of Z. spinosa showed the most potent antibiofilm activity against Pseudomonas aeruginosa ATCC 27853 with MBIC50 = 630 μg/mL. Candida albicans showed the highest sensitivity to the ethanolic extract of Z. spinosa , with MBIC50 = 660 μg/mL. The GC–MS analysis identified β-sitosterol (40.39%), stigmasterol (22.24%), and coumarin (9.25%), as the main components of Z. spinosa ; and linolenic acid (12.68%), linolenic acid ethyl ester (7.31%), arachidonic acid (6.96%), and (Z)-13-docosenamide (6.47%) as predominant compounds in F. aegyptia . The docking analysis revealed that the key compound stigmasterol from Z. spinosa served as superior ligands, penicillin-binding protein four (PBP4) (−7.7 kcal/mol). Conclusion These findings highlight the powerful antimicrobial and antibiofilm activities of F. aegyptia and Z. spinosa , and supporting their prospective role in developing novel anti-infective agents.