Evaluation of the lethality of Porophyllum ruderale essential oil against Biomphalaria glabrata, Aedes aegypti and Artemia salina
The essential oil of flowers and leaves of Porophylum ruderale (Asteraceae) was investigated for its molluscicidal and larvicidal activities, and its toxicities to brine shrimps. The essential oil was analyzed by gas chromatography-mass spectrometry (GC/MS). GC/MS analysis showed a total volatile content of 99.98% in the P. ruderale oil (PREO). The major components in PREO were identified as (E)-β-ocimeno (93.95%), mircene (3.37%), (Z)-β-ocimeno (1.38%) and β-pineno (0.27%). The methodology for the molluscicidal assays involved basically the immersion of Biomphalaria glabrata in the dechlorinated water containing 0.1% (v/v), dimethylsulphoxide (DMSO) and PREO in the concentrations of 20 to 1000 ppm. The values of LC10, LC50 and LC90 were respectively 738.96, 774.82 and 812.43 for B. glabrata. The brine shrimp toxicity tests were conducted using second instar larvae. Stock solutions of samples were prepared by dispersion of (PREO) [1 to 1000 ppm] in 10 ml of sea water containing 1% (v/v) DMSO. The values of LC10, LC50 and LC90 were respectively 571.99, 632.69 and 699.83 for Artemia salina (values in ppm, 95% confidence interval). LC50 values estimated for Aedes aegypti were 132.48 and 173.65 for Porto Dantas and Rockfeller, respectively.
Key words: Phorophyllum ruderale (Asteraceae), chemical composition, molluscicide, larvicide.