Identification of compounds in Olax dissitiflora with larvacidal effect against Anopheles arabiensis

Abstract Bioassay-guided fractionation of the dichloromethane extract of Olax dissitiflora bark has led to the isolation of santalbic acid and a mixture of two closely related compounds (exocarpic acid and octadec-9,11-diynoic acid). The isolated compounds were then evaluated for their larvicidal activity against laboratory-reared larvae of An. arabiensis mosquitoes, a potent malaria vector in South Africa. The mixture of exocarpic acid and octadec-9,11-diynoic acid exhibited the highest larvicidal activity with an EC 50 value of 17.31 μg/ml compared to ximeninic acid which had an EC 50 value of 62.17 μg/ml.