Studies on essential oils, Part 33: chemical and insecticidal investigations on leaf oil of Coleus amboinicus Lour.

✍ Scribed by Gurdip Singh; Om Prakash Singh; Y. R. Prasad; M. P. de Lampasona; C. Catalan

• Publisher: John Wiley and Sons
• Year: 2002
• Tongue: English
• Weight: 63 KB
• Volume: 17
• Category: Article
• ISSN: 0882-5734
• DOI: 10.1002/ffj.1123

✦ Synopsis

Abstract

Chemical investigations of the leaf essential oil of Coleus amboinicus by GC and GC–MS techniques indicated the presence of six components, accounting for 97% of the total oil. The major component was thymol (94.3%), followed by carvacrol (1.2%), 1,8‐cineole (0.8%), p‐cymene (0.3%), spathulenol (0.2%), terpinen‐4‐ol (0.2%) and an unidentified component (1.4%). The oil was insecticidal to white termites (Odontotermes obesus Rhamb.) with 100% mortality at a dose of 2.5 × 10^−2^ mg/cm^3^ for 5 h exposure. This oil was also more active than the synthetic insecticides, Thiodan and Primoban‐20, against termites, although it was ineffective against Tribolium castaneum, a stored product pest. Copyright © 2002 John Wiley & Sons, Ltd.