Antibacterial Activity of Hydroethanolic Extracts of Artemisia annua L., Hibiscus sabdariffa L., and Paronychia argentea Lam. Against Some Clinically Relevant Gram-Positive and Gram-Negative Bacteria

Abstract

Background: Antimicrobial resistance is one of the major challenges in healthcare, leading to more severe infections, higher mortality, and increased healthcare costs. Therefore, exploring new alternatives, such as plant extracts with antimicrobial properties helps to reduce bacterial resistance. Artemisia annua L., Hibiscus sabdariffa L., and Paronychia argentea Lam. are traditionally used for their biological properties, including antimicrobial activity. However, scientific evidence regarding their antibacterial effects against clinically important bacteria remains limited. Methods: Extracts were obtained from the mentioned plants and phytochemically characterized by GC/MS. Phytochemical analysis revealed the presence of fatty acids, phenolic compounds, aliphatic compounds, and terpenoids. Antibacterial activity was evaluated using the diffusion method with a modified Kirby-Bauer technique and the microdilution method employing the massive plate sealing drop approach. Results: All extracts exhibited bacterial inhibition, with H. sabdariffa L. showing the strongest activity against E. coli (256 mg/mL), K. pneumoniae (256 mg/mL), P. aeruginosa (128 mg/mL), Salmonella sp. (128 mg/mL), and S. aureus (64 mg/mL). Conclusions: Hydroethanolic extracts of A. annua L., H. sabdariffa L., and P. argentea Lam. exhibit antibacterial activity against clinically relevant bacteria and represent promising candidates for future preclinical studies.