No abstract

The ethnobotanical uses of Brazilian plants for different injuries and diseases conjoined with local rich biodiversity represent an important resource for research and development. This study aimed to characterise BDEO and its in vitro activity on the third instar larvae (L3) of Cochliomyia macellaria. Groups of 20 L3 were placed on filter paper impregnated with increasing concentrations of 5-30% (v/v), equivalent to 0.79-4.77 μL/cm, solubilised in ethanol or acetone. The major constituents of BDEO were β-pinene (9.94%), D-limonene (9.59%), β-nerolidol (7.93%), caryophyllene (7.69%), spathulenol (6.69), α-muurolene (6.74%) and α-pinene (5.31%). Lethal concentrations of 50% for BDEO on C. macellaria (LC) after 24 and 48 h of exposure were 2.63 and 2.47 μL/cm for ethanol and 9.58 and 8.11 μL/cm for acetone, respectively. Furthermore, larvae cuticle abnormalities and adult deformity were observed. Our data confirm the effectiveness of BDEO as an ecofriendly product against blowflies.

Morphological biomarkers as the histopathological assessment and scanning electron microscopy can be used to establish a diagnosis of structure damage and intoxication of target cells by new biopesticide candidate. In this sense, cuticle damage caused by active substances in larvae exposed to biopesticides can help to elucidate the mode action. Thus, insecticide activity analysis of essential oil of Curcuma longa leaves and its major compound α-phellandrene have proven to be a new biopesticide candidate against third instar larvae (L3) of the Australian blowfly Lucilia cuprina. In this way, groups of 20 L3 were placed on filter paper, impregnated with ranging concentrations (from 0.15 to 2.86 μL/cm2) of C. longa leaves EO and (0.29–1.47 μL/cm2) to α-phellandrene. The extracts were solubilized in ethanol. Progressive darkening in the body of L3, marked reduction of movement, color changes in larval cuticle and dead were observed 6 and 24 h after contact with both extracts.