Antitermitic Activity of Leaf Essential Oils and Components from Cinnamomum osmophleum

Abstract
The antitermitic activities of the essential oils from the leaves of two Cinnamomum osmophloeum clones (A and B) and their chemical ingredients against Coptotermes formosanus Shiraki were investigated according to direct contact application. Results from this experiment have demonstrated that the indigenous cinnamon B leaf essential oil has a more effective antitermitic activity than indigenous cinnamon A leaf essential oil. Furthermore, when cinnamaldehyde, eugenol, and α-terpineol are extracted from indigenous cinnamon leaf essential oil and used at the strength of 1 mg/g, their antitermitic effectiveness is much higher than that using indigenous cinnamon leaf essential oil. Among the congeners of cinnamaldehyde examined, cinnamaldehyde has exhibited the strongest termiticidal property. Keywords: Cinnamomum osmophleum; Coptotermes formosanus; cinnamon leaf; essential oils; antitermitic activity; cinnamaldehyde; eugenol; α-terpineol