Essential Oil Composition of Ruta graveolens L. Fruits and Hyssopus officinalis Subsp. aristatus (Godr.) Nyman Biomass as a Function of Hydrodistillation Time

摘要

The aim of this study was to establish the kinetics regression models for yield and composition of fruit and subsp. aboveground biomass essential oil (EO), collected at different time intervals during the hydrodistillation process. The hypothesis was that collecting the EO fractions during specific time frames may result in EOs with dissimilar composition that may have differential use by the industry. Furthermore, we calculated the kinetics regression models for the composition of EO, isolated by hydrodistillation in a Clevenger-type apparatus and characterized by GC-MS and GC-FID analyses. The EO yield of fruits was 0.39% (relative area % of GC-FID chromatogram), with major constituents in the Control fraction (0–90 min) being 2-nonanone, 2-undecanone, and 2-undecanol, representing 65% of the total oil. The highest concentration of 2-nonanone (60%) was found in the 30–60 min oil fraction, the concentration of 2-undecanone (35%) was highest in the Control (0–90 min) fraction, and the concentration of eucalyptol (19%) was highest in the 5–10 min fraction. The EO yield of subsp. dried biomass was 1.12%. The major constituents in the Control fraction (0–90 min) of biomass were eucalyptol, α-pinene, sabinene, β-pinene, and -3-pinanone, representing 86% of the total. Eucalyptol (58%) was the highest in the 0–5 min fraction. The highest β-pinene (15%) and -3-pinanone (20%) contents were found in the 20–40 min fraction. The kinetics regression models that were developed for EO composition of were second-order polynominal, Michaelis–Menten, and Exponential decay, while for EO composition of subsp. biomass were Exponential decay and Power. The results from this study could benefit the EO industry.