Chemical composition and larvicidal activity against Aedes mosquitoes of essential oils from Arisaema fargesii

BACKGROUND Dengue fever is caused by the spread of dengue virus by Aedes mosquito vectors. Currently, the most effective way to control dengue is by preventing mosquitoes from spreading the disease. Arisaema fargesii is a Chinese herbal medicine commonly used to repel mosquitoes. In our laboratory, anti-mosquito chemical components were extracted from A. fargesii, and the effects of these substances on mosquito larvae were examined. RESULTS In total, 48 compounds corresponding to 98.79% of the total oil were identified and the major compounds identified were linalool (12.38%), carvacrol (8.27%), eugenol (5.21%), and beta-selinene (5.36%). Essential oil had larvicidal activity against Ae. aegypti and Ae. albopictus with LC50 values of 40.49 mg/L, 47.01 mg/L, respectively. The LC50 values of carvacrol, eugenol, linalool and beta-selinene were 32.78, 56.34, 70.56, 136.03 mg/L against Ae. aegypti larvae, and 39.08, 52.07, 82.34, 151.74 mg/L, respectively, against Ae. albopictus larvae. Biochemical assays of Aedes larvae showed that the activities of acetylcholinesterase (AChE), monooxygenases (MO), glutathione-S-transferase (GST), p-Nitrophenyl acetate (p-NPA) esterase, alpha-esterase and beta-esterase were significantly affected by carvacrol. Essential oil induced the detoxification mechanism for the action of GST and MO. CONCLUSION The result indicates that essential oil of A. fargesii and its isolated constituent have good inhibitory effects on the defense enzymes of Aedes mosquito larvae. A. fargesii essential oil can be used to control Aedes mosquito larvae to prevent the spread of dengue fever. (c) 2019 Society of Chemical Industry