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

Abstract

Here, we investigated the reaction mechanism of longifolene autoxidation and the bioactivities of its products. A longifolene sample was autoxidized at 120 °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 °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.