Study on Ultrasonic-Assisted Extraction of Essential Oil from Cinnamon Bark and Preliminary Investigation of Its Antibacterial Activity

摘要

Ultrasonic-assisted extraction of essential oil from cinnamon bark was explored in this study. Effects of different parameters such as solvent, extraction time, powder granularity, ultrasonic power, solid-liquid ratio, and extraction temperature on the yield of essential oil were also investigated through single factor and orthogonal tests. The antibacterial activity of cinnamon oil obtained by ultrasonic-assisted extraction was preliminary determined. Results show that ultrasonic power has the largest effect on the oily yield, followed by powder granularity, time, and solid-liquid ratio. The optimized extraction conditions are as follows: petroleum ether (b.p. 60-90 °C) as extraction solvent, 165 W, 80-100 mesh cinnamon power, 40 min, and 6:60 (W/V) solid-liquid ratio, respectively. And under this condition, cinnamon oil yield can reach 14.8034 %, in which the content of trans-cinnamal-dehyde is 82.62 % by HPLC analysis. Ultrasonic-assisted extraction of essential oil from cinnamon bark is feasible, and it can be used as a good alternative compared with other traditional methods. In addition, antibacterial activity assay demonstrates that cinnamon oil shows a strong inhibitory effect against Escherichia coli and Bacillus subtilis, and it can be applied as a natural antibacterial agent in many areas.