Assessment of Mosquitocidal and Antibacterial Activities of Mixture of Different Extracts of <i>Curcuma amada</i> Rhizome and <i>Tamarindus indica</i> Leaves

Present study aimed at evaluation of mosquito larvicidal and antibacterial activities of mixture of crude and solvent extracts of Curcuma amada rhizome and Tamarindus indica leaf against Culex vishnui larvae and eight pathogenic bacteria. Larvicidal bioassay was performed by graded concentrations of crude, methanol and aqueous extracts. Log-probit analysis for estimation of LC 50 and LC 90 values was performed. ANOVA analysis was also conducted. Effects of the extracts on non-target organisms were also examined. Antibacterial activity was examined through standard methods. Preliminary phytochemical analysis and Fourier Transform Infra Red (FT-IR) spectroscopic analysis of the most potent extract were also done. Highest mortality (100%) was recorded at 100 ppm concentration of methanol extract after 72 hours in 1 st , 2 nd and 3 rd instars larvae. LC 50 and LC 90 values were 72.32 and 131.14 ppm respectively after 24 h for the 3 rd instar larvae. No effects on non-target organisms found. Crude and methanol extracts showed antibacterial activity against all tested bacteria while aqueous extracts showed none. Highest inhibition zone (19.00±0.00 mm) was observed against Pseudomonas fluorescens MTCC 103 by methanolic extract. Preliminary phytochemical screening of most potent extract detected tannins, flavonoids, alkaloids and terpenoids. Presence of various functional groups was revealed by FT-IR analysis. Results confirm the potential mosquito larvicidal and antibacterial activities of mixture C. amada rhizome and T. indica leaf extracts. This approach of using mixture of extracts for getting better result against harmful biological agents is a promising finding which may further approve application of coactivity of bioactive compounds of plant origin.