Influence of Harvesting Method on Essential Oil Composition, Antioxidant Activity, and Operational Efficiency in Anatolian Sage (Salvia fruticosa Mill.)

Salvia fruticosa Mill. (Anatolian sage) is an important medicinal and aromatic plant widely valued for its essential oil and phenolic compounds. Harvesting practices may influence both biomass yield and the chemical quality of plant raw materials. This study evaluated the effects of manual and machine harvesting on selected physical characteristics, essential oil composition, mineral content, and antioxidant-related phytochemical properties of S. fruticosa cultivated under Central Anatolian conditions, together with the operational performance of both harvesting methods. Manual harvesting resulted in higher fresh and dry biomass yields and a greater essential oil content (2.03%) compared with machine harvesting (1.57%). Mineral analysis showed that Ca, Zn, Cu, and B concentrations were higher in manually harvested samples, whereas K and Mg contents were slightly higher in machine-harvested plants. Essential oil characterization demonstrated that 1,8-cineole was the dominant compound and its proportion differed markedly between harvesting methods, reaching 43.07% in manual harvesting and 21.77% in machine harvesting. Antioxidant activity determined by the DPPH assay was 0.093 mg TE mL⁻¹ for manual harvesting and 0.096 mg TE mL⁻¹ for machine harvesting. Additional phytochemical analyses revealed total phenolic contents of 134.6 and 129.3 mg GAE g⁻¹ extract, total flavonoid contents of 22.7 and 25.2 mg QE g⁻¹ extract and FRAP values of 382 and 336 µmol Fe²⁺ g⁻¹ extract for manual and machine harvesting, respectively. These findings indicate that harvesting technique affects certain compositional parameters but causes only limited changes in the overall antioxidant potential of S. fruticosa extracts.