2022 Volume 68 Issue 4 Pages 172-178
In this study, we investigated the antitermitic activity of extracts from Cunninghamia lanceolata trunk and branch heartwood planted in Japan using Reticulitermes speratus. Strong antitermitic activity was observed in the n-hexane extract of C. lanceolata. From GC-MS (Gas chromatography-mass spectrometry) and GC-FID (Gas chromatography-flame ionization detection) analysis, cedrol and isoabienol were detected as the major components of the n-hexane extract of trunk and branch heartwood, respectively. Assays using both isolated components distinctly showed that cedrol exerted antifeedant activity at low concentrations and termiticidal activity at high concentrations, whereas isoabienol exerted only antifeedant activity, even at high concentrations. These results suggested that cedrol and isoabienol in the heartwood of the trunk and branch of C. lanceolata were strongly involved in antitermitic activity against the Japanese termite, R. speratus. Furthermore, the intensity of termiticidal and antifeedant activities exerted by cedrol and isoabienol depended on the concentration of each component in the heartwood.
