Isolation of insecticidal components in Inula salsoloides Ostenf. and characterisation of their activities.

The ethanol extract from Inula salsoloides (Turcz.) Ostenf was found to cause high mortality against Plutella xylostella L. (Lepidoptera: Plutellidae). The active components were isolated and identified. Two compounds were obtained and identified to be inulasalsolin and taraxasterol. Both compounds showed anti-feedant effects against third instar larvae of P. xylostella with AFC of 0.030 and 0.053 mg/mL and insecticidal activities with LC of 0.19 and 0.49 mg/mL, respectively. The two compounds also exhibited high toxicity to cabbage aphid, Brevicoryne brassicae L. (Hemiptera: Aphididae) with LC values of 0.021 and 0.098 mg/mL. This is the first report on the study of insecticidal components of I. salsoloides and their activity against insects.