GC-MS analysis of Eclipta prostrata leaf extracts in relation to larvicidal activity against the mosquito Aedes aegypti

Abstract

The mosquito is the principal vector of many of the vector borne diseases affecting human beings and animals. Several mosquito species vectors for the pathogens of various diseases like malaria, filariasis, Japanese encephalitis, dengue fever, dengue haemorrhagic fever and yellow fever. Repeated use of synthetic insecticides for mosquito control has disrupted natural biological control systems and led to resurgences in mosquito populations. It has also resulted in the development of resistance, undesirable effects on non-target organisms and fostered environmental and human health concern, which initiated a search for alternative control measures. Plants are considered as a rich source of bioactive chemicals and they may be an alternative source of mosquito control agents. They even result in mutation of genes and these changes become prominent only after a few generations. Hence, the present study has been choosen to determine the photochemical screening, compound identification by GC-MS studyand larvicidal activity in various concentratingof Eclipta prostrata leaves extractagainst Aedes aegypti. The phytochemicals such as saponins, tannins, phenols, terpenoids, flavanoids, amino acids and protein, carbohydrates, glycosides were identified in both aqueous and methanol extracts, further revealed that Eclipta prostrata extract exhibited significantly highest larvicidal activity in 400 ppm at 24 hrs of methanol extract when compared to aqueous extract. The GC-MS analysis, showed 16 different compoundsand the compound isopropyl myristate, is found to be present in high area percentage.Further, the result of the currentinvestigation revealed that the methanol extract of Eclipta prostrata possess good larvicidal activity against Aedes aegypti with maximum larvicidal repellent and the numbers of the dead larvae were affected by increasing the concentrations of the plant extracts.