Insecticidal efficacy of the essential oil of jambú (Acmella oleracea (L.) R.K. Jansen) cultivated in central Italy against filariasis mosquito vectors, houseflies and moth pests

Journal of Ethnopharmacology Volume 229, 30 January 2019, Pages 272-279 Journal of Ethnopharmacology Author links open overlay panelGiovanniBenelliaRomanPavelabEttoreDrenaggicFilippoMaggic a Department of Agriculture, Food and Environment, University of Pisa, via del Borghetto 80, 56124 Pisa, Italy b Crop Research Institute, Drnovska 507, 161 06 Prague, Czech Republic c School of Pharmacy, University of Camerino, Via Sant’Agostino 1, Camerino, Italy Received 22 May 2018, Revised 3 August 2018, Accepted 24 August 2018, Available online 25 August 2018. crossmark-logo Show less https://doi.org/10.1016/j.jep.2018.08.030Get rights and content Abstract Ethnopharmacological relevance Acmella oleracea (L.) R.K. Jansen (Compositae), well-known as jambú, is a medicinal herb of pungent taste, native to Brazil but cultivated in different parts of the world due to its aromatic and pharmacological properties. In folk medicine, the plant has been used against parasites and to combat insects and mites. No data are available on the insecticidal activity of jambú essential oil. Aim of the study To test the jambú essential oil obtained from A. oleracea cultivated in central Italy against the filariasis vector, Culex quinquefasciatus, the Egyptian cotton worm, Spodoptera littoralis, and the housefly, Musca domestica. Materials and methods The chemical composition of the essential oil was achieved by GC-FID and GC-MS analyses. Acute toxicity experiments were conducted on larvae of the filariasis vector C. quinquefasciatus and S. littoralis and adults of M. domestica to determine the LC50(LD50) and LC90(LD90) values of the oil, along with the positive control, α-cypermethrin. Results (E)-caryophyllene (20.8%), β-pinene (17.3%), myrcene (17.1%) and caryophyllene oxide (10.0%) were the major volatile constituents. Interestingly, the oil contained little amounts (3.9%) of the insecticidal spilanthol. Jambú essential oil exerted relevant effects on C. quinquefasciatus (LC50 = 42.2 mg L−1, LC90 = 73.6 mg L−1) and S. littoralis 3rd instar larvae (LD50 = 68.1 µg larva-1, LD90 = 132.1 µg larva-1). High acute toxicity was also detected testing the jambú oil against adult females of M. domestica, achieving a LD50 value of 44.3 µg adult-1 and a LD90 value of 87.5 µg adult-1. Conclusions Taken together our data support the traditional use of jambú as an insecticidal agent and represent the scientific basis for the industrial exploitation of the essential oil in the fabrication of green insecticides. Graphical abstract fx1 Download high-res image (180KB)Download full-size image Previous article in issueNext article in issue Keywords Acmella oleraceaEssential oilCulex quinquefasciatusMusca domesticaSpodoptera littoralisGreen insecticides