Extraction and Characterization of Chamomile (<i>Matricaria recutita</i> L.) Essential Oil Using the Green Technology of Solvent-Free Microwave Extraction

Abstract

This study aimed to assess the benefits of the solvent-free microwave extraction (SFME) on chamomile (Matricaria recutita L.) essential oil quality and yield compared to the extraction by steam distillation (SD). The oil obtained by SFME and SD presented a blue color, a solubility in 70% ethanol (v/v) of four, a relative density of 0.929–0.925 g/mL, a refractive index of 1.5013–1.4790, and an acidity value of 6.23 and 3.43, respectively. The yields were significantly different between extraction methods, being the highest (0.5 mL (0.083% v/w)) for SFME and 0.2 mL (0.03%) for SD. The GC-MS analysis showed a marked difference in sesquiterpenes, such as Chamazulene, α-bisabolol, α-bisabolol oxide A, and α-bisabolol oxide B. The SFME had 97% and 20% more content of chamazulene and α-bisabolol respectively, whilst SD had 88% and 12% more content of α-bisabolol oxide A and B, respectively. The results suggest that SME is an outstanding alternative for essential oil extraction due to much higher yield and quality compared to the steam distillation.

Keywords

• chamazulene
• GC-MS
• distillation
• bisabolol
• sesquiterpenes
• yield