Phytochemical Screening and Comparative Larvicidal Activity of Albizia lebbeck and Tamarindus indica Leaf Extracts against Culexquinquefasciatus and Aedesaegypti

Abstract

Different species of mosquitoes have been implicated in the transmission of various diseases to humans and livestock, including malaria, filariasis, dengue fever, encephalitis, etc. This study aimed to evaluate the in vitro larvicidal potentials of Albizia lebbeck and Tamarindus indica against the third instar larvae of two mosquito species, Aedes aegypti and Culex quinquefasciatus. Fresh leaves of the plants were collected, dried, grounded, and extracted separately with petroleum ether in a soxhlet apparatus. The powdered samples were screened for phytochemical constituents using standard methods. The larvicidal potential of both extracts was evaluated using the WHO protocols. Results of the phytochemical screening revealed the presence of alkaloids, glycosides, flavonoids, tannins, saponins, and triterpenoids. The extracts of both plants exhibited significant and dose-dependent mortality of C. quinquefasciatus larvae at 97.33% with LC₅₀ of 0.3092 for A. lebbeck and 98.67%, with LC₅₀ of 0.1729 mL/L for T. indica at extracts concentration of 1.6 mL/L. Also, the extracts showed significant and dose-dependent mortality of A. aegypti larvae with 25-92% mortality and LC₅₀ = 0.2735 mL/L for A. lebbeck and 32-92% for T. indica leaf extracts with LC₅₀  = 0.2889 µg/mL (p≤ 0.006621). We conclude that the extracts of these plants possess larvicidal potentials and could be developed into natural larvicides for mosquito control programs.