Comparison of some biological activities of essential oils and extracts (waste and non-waste) of two species used by people: Salvia macrosiphon Boiss. and Salvia reuteriana Boiss. from natural habitats of Kashan.

Essential oils and plant extracts exhibit potent and diverse biological activities and are consider as major sources for the discovery of novel bioactive agents to address contemporary health and agricultural challenges. The present study was designed and implemented to conduct a comparative and multifaceted evaluation of the biological activities of essential oils and various extracts (waste and non-waste) of two valuable species, Salvia macrosiphon Boiss. and Salvia reuteriana Boiss. from their natural habitats in Kashan. For this purpose, sampling of S. reuteriana was carried out in late May and S. macrosiphon in June 2024. After extracting the essential oil by water distillation using a Clevenger apparatus, the compounds were analyzed and identified using a gas chromatography-mass spectrometer (GC-MS). Different extracts of the two species were prepared by digestion and water solvent. The antimicrobial activity of the essential oil and extracts was evaluated by agar diffusion method and determination of the minimum growth inhibitory and bactericidal concentration and the antioxidant activity of the plant extracts were evaluated by the DPPH method. The results of quantitative analysis of the essential oil showed that the yield of the essential oil of S. macrosiphon 1.05 ± 0.27% was significantly higher than that of S. reuteriana 0.42 ± 0.15%. The dominant compounds in S. macrosiphon were benzyl benzoate (77.45%) and in S. reuteriana were linalool (13.02%) and hexyl isovalerate (9.32%).The aqueous extract of dried S. macrosiphon had the highest antioxidant activity with the lowest IC50 value of (60.50 ± 6.54) µg/mL. The Clevenger plant pulp extract of S. reuteriana showed the strongest antimicrobial effect against S. aureus with a growth inhibition zone diameter (37.5 mm) and E. coli (11 mm). The least and the best MIC value of the essential oil of S. reuteriana against C. albicans was 125 µg/mL. Therefore, the Clevenger plant pulp extract of S. reuteriana as waste could be a potentially potent, cheap and environmentally friendly option against some microorganisms for pharmaceuticals.