Comparative of the different methods for extraction of cinnamon essential oil

Cinnamon essential oil were prepared by steam distillation (SD) , ultrasonic assisted extraction (UAE) , subcritical water extraction (SWE) , and ultrasound-enhanced subcritical water extraction (USWE) . The extraction parameters, composition, physical characteristics and antioxidant activity of cinnamon essential oil were studied comparatively. Results showed that the extraction time of USWE was the shortest (25min) . The yield of cinnamon oil of UAE was the highest (2.10%) , but with low appearance characters. The yield of cinnamaldehyde from cinnamon and the content of cinnamaldehyde in cinnamon oil of USWE were the highest. Four cinnamon oils from different extraction methods shared the same main ingredient:cinnamaldehyde. However, different methods made a great difference in relative content. The physical characteristics of cinnamon oil from SD, SWE and USWE were very similar, but with high difference compared with cinnamon oil of UAE. The scavenging activity of four cinnamon oils on DPPH radical, hydroxyl radical and superoxide anion radicals were excellent, and the scavenging activity increased with increasing concentration of cinnamon oil. The scavenging activity of cinnamon oil of USWE was significantly superior to other three methods. All of these suggested that ultrasoundenhanced subcritical water extraction (USWE) was an ideal method of extraction of cinnamon essential oil and showed shorter extraction time, high efficiency, and good product quality, etc. advantage.