Larvicidal activity of Zanthoxylum acanthopodium essential oil against the malaria mosquitoes, Anopheles anthropophagus and Anopheles sinensis

Qi He, Wenxia Wang, Liang Zhu

Zanthoxylum acanthopodium has insecticidal effect in Chinese traditional medicine. In this study, the essential oil from the dried Zanthoxylum plant was used as a larvicidal compound against the malaria mosquitoes, Anopheles anthropophagus and Anopheles sinensis. Compounds in the Zanthoxylum essential oil were investigated by gas chromatography and mass spectroscopy (GC-MS). The larvicidal bioassays of the whole oil, as well as the main compounds in the oil (estragole and eucalyptol) were performed using WHO method. In total, 63 main compounds (99.32%) were found in the oils, including estragole (15.46%), eucalyptol (10.94%), β-caryophyllene (5.52%), cis-linalool oxide (3.76%), cis-limonene oxide (3.06%). A dose-dependent effect on mortality was recorded with increasing concentrations of essential oil and compounds increasing mortality of the larvae. Larvicidal bioassays revealed that 24 h LC50 of the whole essential oil was 36.00 mg/L and LC90 was 101.49 mg/L against An. anthropophagus, while LC50 was 49.02 mg/L and LC90 was 125.18 mg/L against An. sinensis. Additionally, 24 h LC50 of estragole were 38.56 and 41.67 mg/L against An. anthropophagus and An. sinensis, respectively, while the related LC90 were 95.90 and 107.89 mg/L. LC50 of eucalyptol were 42.41 and 45.49 mg/L against An. anthropophagus and An. sinensis, while the related LC90 were 114.45 and 124.95 mg/L. The essential oil of Z. acanthopodium and its several major compounds may have potential for use in the control of malaria mosquitoes.