Enhancing lavender essential oil yield through optimization of hydrodistillation parameters

This study investigates the hydrodistillation of lavender essential oil from lavender (Lavandula angustifolia L.) on a laboratory scale using a historical data design and response surface methodology. Distillation was conducted in flasks of various volumes (250 to 2000 mL) with different distillation rates and water-to-flower ratios (10:1, 15:1, and 20:1 mL/g). The aim was to optimize process conditions – specifically flask size, distillation rate, and water-to-flower ratio – and evaluate their influence on essential oil yield. A linear relationship between these variables and oil yield was established. ANOVA confirmed the statistical significance of the linear model and all three variables. Optimized conditions (2000 mL flask, 7.5 mL/min distillation rate, 10 mL/g water-to-flower ratio) predicted a maximum yield of 2.28%. The study also analyzed the essential oil’s composition, physicochemical properties, and biological activities, identifying 47 compounds comprising 97.6% of the oil, notably linalool (32.19%) and linalyl acetate (18.29%). The essential oil demonstrated antioxidant activity (EC50 = 10.13 mg/mL) and moderate antimicrobial effects (MICs = 25.7 to 206.6 mg/mL).