Larvicidal and Structure–Activity Studies of Natural Phenylpropanoids and Their Semisynthetic Derivatives against the Tobacco Armyworm Spodoptera litura (Fab.) (Lepidoptera: Noctuidae)

Abstract

The larvicidal activity of 18 phenylpropanoids, 1-18, including phenylpropenoate, phenylpropenal, phenylpropene, and their semisynthetic analogues, were evaluated against the tobacco armyworm, Spodoptera litura (Fab.), to identify promising structures with insecticidal activity. Amongst various phenylpropanoids, isosafrole, a phenylpropene, showed the best activity, with an LC(50) value of 0.6 microg/leaf cm(2), followed by its hydrogenated derivative dihydrosafrole (LC(50)=2.7 microg/leaf cm(2)). The overall larvicidal activity of various phenylpropene derivatives was observed in the following order: isosafrole (6)>dihydrosafrole (16)>safrole (12)>anethole (4)>methyl eugenol (11)>eugenol (13)>beta-asarone (8)>dihydroasarone (18)>dihydroanethole (15). Dihydrosafrole might be a promising compound, although presenting a lower larvicidal activity than isosafrole, because of its better stability and resistance to oxidative degradation (due to the removal of the extremely reactive olefinic bond) in comparison to isosafrole. Such structure-activity relationship studies promote the identification of lead structures from natural sources for the development of larvicidal products against S. litura and related insect pests.

Acaricidal activity of Annonaceae fractions against Tetranychus tumidus and Tetranychus urticae (Acari: Tetranychidae) and the metabolite profile of Duguetia lanceolata (Annonaceae) using GC-MS

“…However, phytochemical studies have indicated that these species produce substances that may have pesticidal activity (NASCIMENTO et al, 2003;PIMENTA et al, 2005;FORMAGIO et al, 2013). Acetylcholinesterase inhibitory activity has been reported for the alcoholic extract from the branches of G. australis, while the same bioactivity was not observed for the leaf extract (CARDOSO-LOPES et al, 2008). This last result is consistent with the inactivity of the G. australis leaf fraction observed in the present study.…”

“…Moreover, the abundance of 2,4,5-trimethoxystyrene and trans-asarone in the D. lanceolata stem bark, as shown by the GC-MS analysis (Figure 1), is consistent with the high activity against T. urticae, since both molecules are known to have insecticidal activity (KOONA; BOUDA, 2006;BHARDWAJ et al, 2010). It is noteworthy that the acaricidal activity of these molecules is supported by the fact that other molecules, also belonging to the phenylpropanoids chemical class, have also been reported to have acaricidal activity.…”

Toxicity of the Essential Oil ofIllicium difengpiStem Bark and Its Constituent Compounds Towards Two Grain Storage Insects

“…Moreover, safrole also possessed larvicidal activity against two mosquitoes, Aedes aegypti and Ae. albopictus (Jantan et al 2005; Cheng et al 2009), as well as the tobacco armyworm, Spodoptera litura (Bhardwaja et al 2010). However, safrole was demonstrated to be anticipated as a human carcinogen based on sufficient evidence of carcinogenicity from studies in experimental animals (United States Department of Health and Human Services 2011).…”

Biopesticides from Natural Products: Current Development, Legislative Framework, and Future Trends

“…However, it is relatively simple to generate many similar chemical structures, using either chemical or biochemical pathways. Thus, the MoA of these compounds can be studied using an approximation of the structure-activity relationship (SAR) (Tewary et al 2006;Bhardwaj et al 2010;Kirst 2010;Li et al 2013). This term describes a rapidly growing field of research that studies relationships between molecular structure (e.g., available hydroxyl (He et al 1997) or polymerization degree (Frackenpohl et al 2009)) and the physicochemical and biological response.…”

“…This term describes a rapidly growing field of research that studies relationships between molecular structure (e.g., available hydroxyl (He et al 1997) or polymerization degree (Frackenpohl et al 2009)) and the physicochemical and biological response. For example, Bhardwaj et al (2010) used this approach to evaluate the larvicidal activity of 18 phenylpropanoids ( Fig. 2), including phenylpropenoate, phenylpropenal, phenylpropene, and their semisynthetic analogues against the tobacco armyworm, Spodoptera litura.…”