Assessment of Achyranthes aspera induced toxicity and molecular analysis of RAPD-PCR profiles of larval genomic DNA of Aedes aegypti L. (Diptera: Culicidae).

Abstract

Current studies investigated the anti-mosquito potential of Achyranthes aspera against the dengue vector, Aedes aegypti. The stems and leaves of A. aspera were extracted in hexane and evaluated for their toxicity against early fourth instars of A. aegypti. The larvicidal efficacy of the extract was validated as per WHO protocol. The mortality counts were made after 24h and LC values were calculated at different levels. The adverse impact of extracts was also explored on the larval genomic DNA. The larvae were exposed to extracts at LC50 levels and the alterations in g-DNA was evaluated through RAPD-PCR technique using three random primers; MA-09, MA-12 and MA-26. Our investigations ascertained the larvicidal efficacy of both the leaf and stem extracts of A. aspera resulting in respective LC50 values of 0.068 and 0.082mg/mL. The extracts also caused variable genotoxic effects with significant changes in the RAPD profiles. The results showed appreciable modifications in larval g-DNA with loss of certain bands and gain of unique bands with 82.35% DNA polymorphism. These alterations suggest the probable DNA damage and mutations in the larval g-DNA caused by certain phytocomponents which could be the possible reason of larval mortality. Our studies evidenced the anti-mosquito potential of A. aspera extracts against A. aegypti causing appreciable larval mortality and significant changes in g-DNA. The A. aspera extracts are suggested as efficient and eco-friendly control agent against A. aegypti, yet further investigations are needed to identify the bioactive constituent and ascertain its effectiveness in the field conditions.