Phytochemical Characterization and Antibacterial Activity of Carthamus Caeruleus L. Aqueous Extracts: In Vitro and In Silico Molecular Docking Studies

In order to valorize natural resources and the traditional use of medicinal plants in Algeria, this study exploits the antibacterial effect of Carthamus caeruleus L. Since there are few studies on this plant despite its notable therapeutic potential, this work aims to characterize the chemical composition of Carthamus caeruleus L. leaf and root aqueous extracts and to evaluate their antibacterial activity through an in vitro and in silico studies. Spectrophotometric assays and HPLC results revealed 22 components in the roots and 16 in the leaves. Disc diffusion and microdilution methods were used to study the antibacterial properties against nine standard bacterial strains. The results showed that roots exhibited the best activity on most tested strains. Both extracts were also able to inhibit the growth of Staphylococcus aureus ATCC 25923 and Escherichia coli ATSC 25922. Furthermore, no nucleic acid leakage or membrane damage was detected. However, molecular docking of the molecules indicates that some constituents have significant affinity and stability for DNA gyrase. Gallic acid, luteolin, myricetin, and orientin were found to have the highest score. The molecular docking data suggest, for the first time, that the antibacterial activity may be caused by the inhibition of DNA gyrase.