Toxicological Evaluation of Essential Oil From the Leaves ofCroton argyrophyllus(Euphorbiaceae) onAedes aegypti(Diptera: Culicidae) andMus musculus(Rodentia: Muridae)

Abstract

Plant-derived essential oils can be used as insecticides for vector control. However, to establish their safety, it is necessary to perform toxicological studies. Herein, we evaluated the chemical composition and insecticidal activity of the essential oil from the leaves of Croton argyrophyllus on the third- and fourth-instar larvae and adult Aedes aegypti (L., 1762). We also evaluated the acute toxicity of the essential oil in adult female Mus musculus. The lethal concentration 50 (LC50) and 90 (LC90) of C. argyrophyllus essential oil on larvae of Ae. aegypti were 0.31 and 0.70 mg ml-1, respectively, and 5.92 and 8.94 mg ml-1, respectively, on Ae. aegypti adults. The major components of the essential oil were spathulenol (22.80%), (E)-caryophyllene (15.41%), α-pinene (14.07%), and bicyclogermacrene (10.43%). It also displayed acute toxicity in adults of Mus musculus; the intraperitoneal and oral lethal dose 50 (LD50) were 2,000 mg kg-1 and 2,500 mg kg-1, respectively. The results showed that the essential oil from C. argyrophyllus leaves has insecticidal activity on Ae. aegypti larvae and adults at an average lethal concentration below the median lethal dose needed to cause acute toxicity in the common mouse.

Chemodiversity and Antibacterial Activity of the Essential Oil of Leaves of Croton argyrophyllus

“…The chemical composition of oils from C. argyrophyllus has been investigated and has been revealed that chemotypes containing main constituents like bicyclogermacrene, ( E )‐caryophyllene and spathulenol are among the most widely known [9,21–24] . The composition of the chemotype that is presented in this paper, with bicyclogermacrene, ( Z )‐caryophyllene, germacrene B and epi ‐longipinanol as the main constituents, is different from those previously registered in the literature.…”

“…The chemical composition of oils from C. argyrophyllus has been investigated and has been revealed that chemotypes containing main constituents like bicyclogermacrene, (E)-caryophyllene and spathulenol are among the most widely known. [9,[21][22][23][24] The composition of the chemotype that is presented in this paper, with bicyclogermacrene, (Z)-caryophyllene, germacrene B and epi-longipinanol as the main constituents, is different from those previously registered in the literature. This variation in the composition in relation to previous studies, may be due to several factors such as the specific location of where the plant was collected, vegetative cycle, botanical origin, climate factors.…”

“…The main compound found in the population investigated was bicyclogermacrene in concentrations ranging from 21.4 % to 62.9 % (average: 38.4 %), which presented a very high amount in relation to the analysis of other oils of this species. [9,[21][22][23][24] It was followed by (Z)-caryophyllene, ranging from 5.4 % to 23.6 % (average: 14.1 %), which did not show significant concentrations in previous studies, [9,[21][22][23][24] which was followed by germacrene B, ranging from 2.3 % to 16.8 % (average: 9.1 %) and present in all samples, and then epi-longipinanol with a range from 5.1 % to 14.2 % (average: 9.78 %), present in eight samples and is being identified for the first time in C. argyrophyllus essential oil. Furthermore, common sesquiterpenes occurring in nearly all samples in low proportions were β-elemene, spathulenol and caryophyllene oxide.…”

“…[20] The chemical composition and insecticidal, antimicrobial, antioxidant, cytotoxic, anti-inflammatory, antinociceptive and gastroprotective activities of C. argyrophyllus essential oil have been studied, mainly in the plants in northeastern Brazil. [21][22][23][24] However, these studies demonstrated great differences in the reported oil compositions, including the major identified compounds. Like in many other plant species, these chemical variations can be attributed to genetic and environmental factors, in addition to the conditions related to the extraction process or time of collection.…”

“…The chemical composition and insecticidal, antimicrobial, antioxidant, cytotoxic, anti‐inflammatory, antinociceptive and gastroprotective activities of C. argyrophyllus essential oil have been studied, mainly in the plants in northeastern Brazil [21–24] . However, these studies demonstrated great differences in the reported oil compositions, including the major identified compounds.…”