Natural autoxidation of longifolene and anti-termite activities of the products

Here, we investigated the reaction mechanism of longifolene autoxidation and the bioactivities of its products. A longifolene sample was autoxidized at 120 degrees C or room temperature, and the products were analyzed by gas chromatography. Longicamphenylone, norlongilactone, isolongifolic acid, longifolic acid, and longifolene-hydroxy ketone were detected as the products in the autoxidation at 120 degrees C. During the reaction, longifolene was converted into the other autoxidation products via the formation of longifolene oxide as an intermediate. Anti-termite activities of the longifolene and its autoxidation products were examined against a Japanese subterranean termite (Reticulitermes speratus Kolbe) by paper disk methods in Petri dishes. Longifolene and the autoxidation products exhibited anti-R. speratus activities, and all the autoxidation products had stronger termiticidal and antifeedant activities than longifolene.