A study of the larvicidal activity of twoCrotonspecies from northeastern Brazil againstAedes aegypti

Abstract

The essential oils of Croton heliotropiifolius Kunth (Euphorbiaceae) and Croton pulegiodorus Baill. were selected for larvicidal evaluation against Aedes aegypti L. (Diptera: Culicidae) and studied qualitatively and quantitatively by GC and GC-MS. Sixty-one compounds representing 92.03% (C. heliotropiifolius) and 85.68% (C. pulegiodorus) of the essential oils, respectively, have been identified. The major components of C. heliotropiifolius essential oil were identified as beta-caryophyllene (35.82%), bicyclogermacrene (19.98%), and germacrene-D (11.85%). The major components in C. pulegiodorus essential oil were identified as beta-caryophyllene (20.96%), bicyclogermacrene (16.89%), germacrene-D (10.55%), tau-cadinol (4.56%), and beta-copaen-4-alpha-ol (4.35%). The essential oil of C. pulegiodorus (LC50 159 ppm) was more effective against Ae. aegypti than that of C. heliotropiifolius (LC50 544 ppm). In order to verify whether the major compound of both essential oils is the active principle responsible for the larvicidal activity, beta-caryophyllene was purchased and its larvicidal potential was further evaluated. However, beta-caryophyllene (LC50 1038 ppm) showed weak larvicidal potency. Results of larvicidal evaluation suggest the existence of a synergistic effect of minor components in the essential oils.

Toxicity of essential oils of Piper marginatum Jacq. against Tetranychus urticae Koch and Neoseiulus californicus (McGregor)

“…Among the major components, only β-caryophyllene and patchoulol, which were found in different proportions in stem, flower, and leaf oils, and it demonstrated acaricidal activity. The biological properties of β-caryophyllene have been confirmed in previous reports involving the larvae of Aedes aegypti (Diptera: Culicidae) (Dória et al, 2010) and T. urticae (Araújo et al, 2012). Moreover, the major constituents are not the only components responsible for the fumigating action observed in the experiments and it is likely that these compounds act in synergy with those found in smaller amounts .…”

FUMIGATION TOXICITY OF ESSENTIAL OILS AGAINST Rhyzopertha dominica (F.) IN STORED MAIZE GRAIN

“…Bitter orange essential oil exhibited limonene (90.78%) and myrcene (3.87%) as main compounds. According to Dória et al (2010), "velaminho" essential oil had β-caryophyllene (20.96%), bicyclogermacrene (16.89%), and germacrene D (10.55%) as major components. d) Fumigation -to evaluate the fumigant effect, glass containers (bomboniere) were used as fumigation chambers (1 L), where 10 R. dominica adults were confined.…”

Antifungals and acetylcholinesterase inhibitors from the stem bark of Croton heliotropiifolius

“…The leaves and bark are used either as infusions or pills for the treatment of gastrointestinal disturbances and weight loss (Govaerts et al, 2000). The essential oil of C. heliotropiifolius presented a significant larvicidal activity against Aedes aegypti (Doria et al, 2010) while the ethanolic extract demonstrated an interesting insecticidal activity against Sitophilus zeamais (Silva et al, 2012).…”