Larvicidal Activity of Acridone Alkaloids from Zanthoxylum leprieurii against the Malaria Vector Anopheles gambiae

Three acridone alkaloids, 1-hydroxy-3-methoxy-9-acridone 1, 1-hydroxy-3,4-dimethoxy-10-methyl-9-acridone 2, and 1-hydroxy-3-methoxy-10-methyl-9-acridone 3 were isolated from the plant Zanthoxylum leprieurii (Rutaceae) and evaluated for mosquito larvicidal activity against the malaria vector Anopheles gambiae. The mortalities of the larvae were determined after 24 hours. The results of the larvicidal tests demonstrated that compound 1 was the most potent with LC50 and LC90 values of 39.61 and 77.53 ppm, respectively. Compound 2 produced over 75% mortality at a concentration of 250 ppm and had LC50 and LC90 values of 189.76 and 475.41 ppm, respectively. Compound 3 was less potent and achieved only 33% mortality at a concentration of 1000 ppm. Compounds 1 and 2 showed a mortality of up to 100% of the larvae population tested and this can certainly help reduce the mosquito population drastically. Considering that a large proportion of the human population living in malaria prone areas suffer from varying degrees of poverty, the discovery of compounds from plant extracts that may control the mosquito population could be of great value.