Activity of enzyme Esterase, Glutathione S Transferase and Inorganic Substance of Dengue vector Aedes aegypti larvae against Lansium domesticum leave extract and fractionation

Abstract

Backgound: Dengue vector control using chemical insecticides for a long time on the same target encourages the rapid development of a resistant dengue vector population of Aedes aegypti. Therefore, an alternative method is needed in the form of the use of plant-based insecticides, Lansium domesticum or duku has been proven to contain secondary metabolites that have the potential as insecticides. This study was conducted to measure the activity of enzyme esterase and glutathione S-transferase, as well as to observe the concentration of inorganic substances such as Fe, Mg, Na, and K in Ae. aegypti larvae exposed to L. domesticum extract using methanol as the solvent and fractionation using hexane, butanol, and ethyl acetate as the solvents. Methods: This study used Ae. aegypti larvae and L. domesticum leaves extract and fraction. Esterase activity was measured using a spectrophotometer at λ = 490 nm and obtained as light absorption per minute per mg protein. GST activity was measured using a spectrophotometer at λ = 340 nm and expressed as light absorption per minute per mg protein. Inorganic substance level was evaluated by the absorbance of the atoms using an atomic absorption spectrophotometer which was analyzed at certain wavelengths of each atom according to Beer's law equation Results: The results showed LD50 and LD90 of the crude extract of L. domesticum were 2200ppm and 3200ppm after 24 hours of observation. Crude extract and the fraction of L. domesticum leaf influenced the development of Ae. Aegypti. It reduced the activity of the esterase enzyme. Meanwhile, it increased the GST enzyme activity of Ae. aegypti larvae as well as affects the levels of inorganic substances in Ae. aegypti larvae. Conclusion: Thus, L. domesticum as a plant-based insecticide is an alternative to control the vector whose target is more selective and safe.