Antimosquito activity of aqueous kernel extract of soapnut Sapindus emarginatus: impact on various developmental stages of three vector mosquito species and nontarget aquatic insects

Abstract

Aqueous (physiological saline) extracts of seed kernel from seven indigenous plants were initially screened for their antimosquito activity against eggs, larvae of all instars, and pupae of Aedes aegypti. Among various seed kernels tested, the soapnut Sapindus emarginatus (Sapindaceae) extract was found to exhibit, for the first time, a strong antimosquito activity as evident from its ability to inflict 100% mortality of all the developmental stages of A. aegypti. Furthermore, the kernel extract of S. emarginatus also exerted ovicidal, larvicidal, and pupicidal activity against two other important vector mosquitoes, namely, Anopheles stephensi and Culex quinquefasciatus. Differential susceptibility of the various developmental stages of the three mosquito species exposed to soapnut extract was also noticed. The kernel extract was found to be safe for two nontarget aquatic insects tested: the larvae of Chironomus costatus and the nymphs of Diplonychus rusticus. Lethal concentration values of soapnut extract to these nontarget insects were always threefold or fivefold higher than those that produced 100% mortality of the larvae of the three mosquito species examined. The findings of this study clearly demonstrate that the aqueous kernel extract of S. emarginatus has potent antimosquito activity detectable against all the developmental stages of three important vector mosquito species as well as it is safe for nontarget aquatic organisms, and thus this new botanical resource could be used as an eco-friendly alternative biocidal agent in control of mosquitoes.

Entomotoxicity Properties of Eco-Friendly Crude Protein Extract From Manilkara Zapota Seed against Asian Tiger Vector Aedes Aegypti

“…Especially the first and second instar of this species were more susceptible and bring 100 % mortality to the extract at the 6 to 8 mg/ml, when compared to other larval developmental stages. In a similar study [39] were reported likewise that, the soapnut S. emarginatus has inflicted potent antimosquito activity against all the developmental stages of A. aegypti than other mosquito strains of C quinquefasciatus especially fourth stage larvae and pupae was has less susceptible of soap nut extract. By contrast the Ramanibai et al [40] were reported the strongest Ovicidal, larvicidal and pupicidal activity of A. squamosa aqueous soluble extract against all the developmental stages of A. aegypti, particularly all the larval instar.…”

“…The similar studies Ramanibai et al [40] were also reported that the A. squamosa seed extract also not affected tested aquatic insect C. costatus at their tested concetration. In addition Koodalingam et al [39] were also reported same studies with some disadvantage antimosquito activity of S. emarginatus has produced mortality against two non target aquatic organisms tested, Chironomus costatus (fourth instar larvae) at LC 50 5.71 and LC 50 4.78 and for Diplonychus rusticus (first instar nymphs) at LC 50 9.29 LC 50 8.26 for 24 and 48 h exposed for 24 and 48 h exposed. But in our studies the M. zapota seed has not produced any mortality at tested concentration.…”

Synthesis of pediculocidal and larvicidal silver nanoparticles by leaf extract from heartleaf moonseed plant, Tinospora cordifolia Miers

“…Bansal et al (2009) reported that the 24 h LC 50 values as observed for aqueous extracts for green unripe and yellow ripe fruits were 112.7, 498.2, and 846.3 mg/L and 104.7, 267.7, and 832.2 mg/L for A. stephensi, A. aegypti, and C. quinquefasciatus, respectively. Aqueous (physiological saline) extracts of seed kernel from soapnut Sapindus emarginatus (Sapindaceae) was found to exhibit, a strong antimosquito activity as evident from its ability to inflict 100% mortality of all the developmental stages of A. aegypti (Koodalingam et al 2009). …”

Larvicidal activity of lignans from Phryma leptostachya L. against Culex pipiens pallens

“…The crude hexane extract obtained from the leaf of Leucas aspera was tested for the larvicidal activity against Culex quinquefasciatus and Aedes aegypti (Maheswaran et al 2008); the acetone, chloroform, ethyl acetate, hexane, and methanol leaf extracts of Ocimum canum, Ocimum sanctum, and Rhinacanthus nasutus were studied for antifeedant and larvicidal activity against the fourth instar larvae of Spodoptera litura, Aedes aegypti, and Culex quinquefasciatus (Kamaraj et al 2008a). The aqueous extracts of seed kernels of Pongamia glabra, Adenanthera pavonina, and Sapindus emarginatus were found to exhibit effective ovicidal, larvicidal, and pupicidal activity on Aedes aegypti (Koodalingam et al 2009). The crude methanol, dichloromethane, and hexane extracts of Cestrum nocturnum caused mortality on the second, third, and fourth instar larvae of Aedes aegypti (Chandrashekhar et al 2011); the hexane extracts of Aegle marmelos and Andrographis paniculata revealed potential repellent, ovicidal, and oviposition activity against Culex tritaeniorhynchus ; the crude leaf acetone, chloroform, hot water, methanol, petroleum ether, and water extracts of Calotropis procera R.…”