Larvicidal activity of Blumea eriantha essential oil and its components against six mosquito species, including Zika virus vectors: the promising potential of (4E,6Z)-allo-ocimene, carvotanacetone and dodecyl acetate.
The effective and environmentally sustainable control of mosquitoes is a challenge of essential importance. This is due to the fact that some invasive mosquitoes, with special reference to the Aedes genus, are particularly difficult to control, due to their high ecological plasticity. Moreover, the indiscriminate overuse of synthetic insecticides resulted in undesirable effects on human health and non-target organisms, as well as resistance development in targeted vectors. Here, the leaf essential oil (EO) extracted from a scarcely studied plant of ethno-medicinal interest, Blumea eriantha (Asteraceae), was tested on the larvae of six mosquitoes, including Zika virus vectors. The B. eriantha EO was analyzed by GC and GC-MS. The B. eriantha EO showed high toxicity against 3rd instar larvae of six important mosquito species: Anopheles stephensi (LC50=41.61 μg/ml), Aedes aegypti (LC50=44.82 μg/ml), Culex quinquefasciatus (LC50=48.92 μg/ml), Anopheles subpictus (LC50=51.21 μg/ml), Ae. albopictus (LC50=56.33 μg/ml) and Culex tritaeniorhynchus (LC50=61.33 μg/ml). The major components found in B. eriantha EO were (4E,6Z)-allo-ocimene (12.8%), carvotanacetone (10.6%), and dodecyl acetate (8.9%). Interestingly, two of the main EO components, (4E,6Z)-allo-ocimene and carvotanacetone, achieved LC50lower than 10 μg/ml on all tested mosquito species. The acute toxicity of B. eriantha EO and its major constituents on four aquatic predators of mosquito larval instars was limited, with LC50ranging from 519 to 11.431 μg/ml. Overall, the larvicidal activity of (4E,6Z)-allo-ocimene and carvotanacetone far exceed most of the LC50calculated in current literature on mosquito botanical larvicides, allowing us to propose both of them as potentially alternatives for developing eco-friendly mosquito control tools.
Department of Agriculture, Food and Environment, University of Pisa, via del Borghetto 80, 56124, Pisa, Italy. benelli.giovanni@gmail.com.
Giovanni
G
Benelli
Unit of Vector Control, Phytochemistry and Nanotechnology, Department of Zoology, Annamalai University, Annamalainagar, Tamil Nadu, 608 002, India. drgovind1979@gmail.com.
Marimuthu
M
Govindarajan
Unit of Vector Control, Phytochemistry and Nanotechnology, Department of Zoology, Annamalai University, Annamalainagar, Tamil Nadu, 608 002, India.
Mohan
M
Rajeswary
Unit of Vector Control, Phytochemistry and Nanotechnology, Department of Zoology, Annamalai University, Annamalainagar, Tamil Nadu, 608 002, India.
Sengamalai
S
Senthilmurugan
Unit of Vector Control, Phytochemistry and Nanotechnology, Department of Zoology, Annamalai University, Annamalainagar, Tamil Nadu, 608 002, India.
Periasamy
P
Vijayan
Department of Botany and Microbiology, College of Science, King Saud University, Riyadh, 11451, Saudi Arabia.
Naiyf S
NS
Alharbi
Department of Botany and Microbiology, College of Science, King Saud University, Riyadh, 11451, Saudi Arabia.
Shine
S
Kadaikunnan
Department of Botany and Microbiology, College of Science, King Saud University, Riyadh, 11451, Saudi Arabia.
Jamal M
JM
Khaled
D000085:Acetates / Q000494:pharmacology*; D000080462:Acyclic Monoterpenes; D000330:Aedes / Q000254:growth & development*; D000818:Animals; D000852:Anopheles / Q000254:growth & development*; D019659:Asteraceae / Q000737:chemistry; D003465:Culex / Q000254:growth & development*; D006801:Humans; D007306:Insecticides / Q000494:pharmacology*; D007814:Larva / Q000254:growth & development; D009032:Mosquito Control / Q000379:methods; D000072138:Mosquito Vectors / Q000254:growth & development*; D009822:Oils, Volatile / Q000494:pharmacology*; D010936:Plant Extracts / Q000494:pharmacology; D018515:Plant Leaves / Q000737:chemistry; D011090:Polyenes / Q000494:pharmacology*; D013729:Terpenes / Q000494:pharmacology*; D000071244:Zika Virus / Q000254:growth & development; D000071243:Zika Virus Infection / Q000635:transmission
D000085:Acetates; D000080462:Acyclic Monoterpenes; D007306:Insecticides; D009822:Oils, Volatile; D010936:Plant Extracts; D011090:Polyenes; D013729:Terpenes; C000618431:carvotanacetone; C015659:alloocimene; C044215:lauryl acetate
GC-MS; WHO; biopesticide; biosafety; essential oil; larvicidal activity; non-target toxicity