Larvicidal activity in desert plants of the Negev and Bedouin market plant products

Aqueous plant extracts of 63 desert plants collected in the Negev desert and Bedouin market (Beer Sheva) were screened for larvicidal activity. Larvicidal activity was found in 16 plants, of which seven were reported in the ethnobotanical literature to be either poisonous, vermifuge, abortive, or toxic. Seven species showed high toxicity against Aedes aegypti larvae: Ephedra aphylla, Gypsophila arabica, Anabasis articulata, Mesembryanthemum nodiflorum, Nicotiana rustica, Hammada scoparia, Achillea fragrantissima. Four species showed moderate toxicity: Foeniculum vulgare, Glaucium arabicum, Solanum elaeagnifolium and Peganum harmala. The species with the lowest LC₅₀ values are: Ephedra aphylla, Gypsophila arabica and Achillea fragrantissima and may be candidates for further isolation and characterization of larvicidal compounds, which could be important in controlling disease-causing mosquitoes. Cytotoxicity of aqueous extract of Gypsophila arabica on melanoma cells in vitro showed that screening for larvicidal compounds may be used as a preliminary screening step in the search of anti-cancerous compounds.