Evaluation of the Inhibitory Effects of Cress Seed (Lepidium sativum) Extracts Prepared in Different Solvent Systems

The global rise in antibiotic resistance necessitates the discovery of novel and effective natural antimicrobial agents. In this context, this study was conducted to determine the biological potential of cress (Lepidium sativum) seeds, known for their therapeutic properties, by comparatively evaluating the antimicrobial efficacy of extracts obtained via Soxhlet extraction using methanol and hexane solvents. The activities of the extracts, prepared at concentrations of 30, 15, and 6 mg/mL, were analyzed against Bacillus subtilis, Staphylococcus aureus, Escherichia coli, Enterobacter aerogenes, and various Candida species using the disc diffusion method in accordance with CLSI standards. Research findings revealed that while the methanol extract remained ineffective against bacterial species and showed limited antifungal activity against certain yeast species, the hexane extract exhibited a significantly more pronounced and broad-spectrum inhibition against both Gram-positive and Gram-negative bacteria, as well as yeast species, in a concentration-dependent manner. In conclusion, it was determined that solvent polarity plays a decisive role in the extraction of bioactive components and antimicrobial efficacy, with non-polar hexane being more successful in recovering lipophilic components. These data indicate that the L. sativum hexane extract is a potential candidate for the development of natural antimicrobial agents and provides a strong foundation for further isolation studies.