Comprehensive analysis of bioactive compounds in <i>Hyssopus officinalis</i> L. and evaluation of its antioxidant, antibacterial, and anti-Alzheimer properties

Introduction: The persistent global challenges of oxidative stress-related diseases, bacterial infections, and neurodegenerative disorders such as Alzheimer’s disease highlight the critical need for effective therapeutic solutions. Hyssopus officinalis has shown promise in traditional medicine for its antioxidant, antibacterial, and neuroprotective properties. This study evaluated the antioxidant, anti-Alzheimer, and antibacterial capacities of ethyl acetate extracts from the leaves (EAL) and stems (EAS) of H. officinalis, as well as total phenolic and flavonoid content (TPC/TFC) and metabolite profiling. Methods: 1,1-Diphenyl-2-picrylhydrazyl (DPPH), 2,2’-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid (ABTS), and Ferric reducing antioxidant power (FRAP) techniques were used to assess the antioxidant activity. Ellman’s method was used to evaluate anti-cholinesterase capacity. The agar well diffusion method was employed to assess the antibacterial effects. Folin-Ciocalteu and aluminum colorimetric techniques were used to investigate the TFC/TPC levels. The phytochemical compounds were recognized by UPLC-ESI-MS/MS. Results: Twenty phytochemical compounds from different classes were identified. EAL exhibited high DPPH and ABTS scavenging activities comparable to butylated hydroxyanisole (BHA) and butylated hydroxytoluene (BHT), with a FRAP value surpassing α-tocopherol and close to ascorbic acid (P&lt;0.05). All extracts demonstrated antibacterial activity comparable to gentamicin against gram-positive bacteria. EAS possessed a strong antibacterial effect at lower concentrations against Staphylococcus aureus and demonstrated a moderate inhibitory action against acetylcholinesterase (AChE), comparable to galantamine (P &lt; 0.05). All extracts had high levels of TPC and TFC. Conclusion: Hyssopus officinalis contains a rich array of bioactive compounds with antioxidant, antibacterial activities, and anti-Alzheimer properties; however, these effects should be confirmed by clinical trials.