Abstract

Calamintha incana (C. incana), a wild aromatic plant native to the Mediterranean region, was investigated for its antioxidant and antimicrobial properties. The plant essential oil was extracted via steam distillation (SD) and chemically characterized in our previous studies using Gas Chromatography–Mass Spectrometry (GC-MS). In this work, its antioxidant activity was evaluated using the 2,2’-Diphenyl-1-picrylhydrazyl (DPPH) assay and compared to the standard antioxidant, Butylated Hydroxytoluene (BHT). The results showed that the oil exhibited moderate free radical scavenging activity that increased with time and concentration but remained lower than BHT, likely due to its lower phenolic content. The antimicrobial potential of the oil was assessed using the disc diffusion method against a range of microorganisms, including Staphylococcus aureus, Escherichia coli, Salmonella typhimurium, Candida albicans, and Saccharomyces cerevisiae. The oil demonstrated strong activity, outperforming gentamicin against Escherichia coli and Salmonella, and exceeding the effectiveness of nystatin against both fungi. However, it showed no activity against Staphylococcus epidermidis. The oil’s antimicrobial effects are probably attributed to bioactive compounds present in the oil such as pulegone and carvone.

Keywords

Calamintha incana, essential oils, antioxidant activity, antimicrobial activity, DPPH assay, gram-positive bacteria, gram-negative bacteria