Culex mosquitoes play a vital role in transmitting pathogens which continue to have a harmful impact on human beings. Indeed, Innovative vector control strategy like use of plant extracts as alternative sources of insecticidal and larvicidal agents against vector-borne diseases has become unavoidable. In this context, the purpose of the present search was to explore the larvicidal properties of Jatropha curcas L. leaf and seed extracts against Culex pipiens L. The larvicidal activity was evaluated in eight different provenances recently introduced in Tunisia (Tanzania (ARU), Mozambique (MOZ), Surinam (SUR) and Brazil represented by five provenances: Paraná (PAR), Norte de Minas (NMB), Mato Grosso (MGB), Regiao Sureste (RSB) and Vale do Fequitinhonha (VFB). The assessment of larval activity showed after 24 h of exposure, 100% mortality for aqueous seed extract and between 60 and 100% for aqueous leaf extract according to provenances. Highest mortality is observed at 1 mg/ml against C. pipiens L with LC 50 values of 0.49 and 0.5% for aqueous seed extract and leaf extract, respectively. Commonly, the mortality increase with the increase in concentration of each extract. However, the inhibitory effect of seeds extract on C. pipiens was more pronounced than that of leaves. These results suggest that the aqueous seed and leaf extracts of J. curcas have the potential to be used as an ideal eco-friendly compound for the control of hurtful mosquito larvae.

With the emergence of multidrug-resistant organisms, combining medicinal plants with synthetic medicines against resistant bacteria becomes necessary. In this study, Synergism between plants extracts (methanolic extract, essential oils) of Inula viscosa and Anacyclus valentinus and two commonly used antibiotics: gentamycin and oxacillin were investigated on three bacterian strains Escherichia. coli, Bacillus subtilis and Staphylococcus aureus. In the first time, the antibacterial effect of extracts alone was tested against 7 strains by disc diffusion and microdilution methods. The minimum inhibitory concentrations of methanolic extracts ranged between 6.25 and 50mg/ml while that of the essential oils varied between 12.5 and 100µL/mL. The inhibitory concentrations of antibiotics varied between 125 and 31.25 µg/ml. Interactions extracts /antibiotics and extracts/extracts were determined by disc diffusion agar and by checkboard. The results show that the synergistic effect of combinations plant extracts/antibiotics was more important than extracts/extracts.