Insecticidal and Mutagenic Evaluation of Two Annonaceous Acetogenins

Abstract

Annonaceous acetogenins represent a new class of bioactive compounds whose primary mode of action is the inhibition of NADH-ubiquinone oxidoreductase. Given the potential pesticidal use of such a class of compounds, we have further evaluated the antifeedant and insecticidal effects of squamocin and annonacin, two annonaceous acetogenins, on Spodoptera littoralis, Leptinotarsa decemlineata, and Myzus persicae. Additionally, to partially assess their environmental risk, we have also tested their mutagenicity in Salmonella typhimurium strains TA98, TA100, and TA102 in the presence and absence of a metabolic activation system. Among the test compounds, annonacin showed antifeedant effects on L. decemlineata, while squamocin was toxic to L. decemlineata and M. persicae. Neither acetogenin was mutagenic, although both were toxic in the absence of a metabolic activation system. We compared these results with those obtained with rotenone, a well-known respiratory inhibitor that was highly toxic to L. decemlineata and M. persicae and showed no mutagenicity/toxicity in the S. typhimurium strains tested up to a concentration of 1000 microg per plate.

<i>In vitro</i> and <i>in vivo</i> antiplasmodial activity of extracts from <i>Polyalthia suaveolens, Uvaria angolensis and Monodora tenuifolia</i> (Annonaceae)

“…Indeed, these compounds have been shown to inhibit complex I (NADH: ubiquinone oxidoreductase) in mitochondrial electron transport systems (Lewis et al, 1993); in addition, they are potent inhibitors of NADH oxidase of plasma membranes (Morré et al, 1995); these enzymes are all found in P. falciparum and the effects of inhibitors impair parasite oxidative and cytosolic ATP production, leading to apoptosis. Acetogenins have been also reported as potent cytotoxics with insecticidal, ascaricidal, fungicidal, antiparasitic, bactericidal and antiplasmodial activities (Rakotomanga et al, 2004;Guadaño et al, 2000). Beside the few previous works reported above, Boyom (2004) also showed that essential oils from the stem bark of P. suaveolens and U. angolensis have in vitro inhibitory potential against P. falciparum W2.…”

Natural and Derivatized Acetogenins Promising for the Control of &lt;i&gt;Spodoptera frugiperda&lt;/i&gt; Smith

“…Methoxy methylated derivatives, squamocin (MOM) (14) and motrilin (MOM) (15) were obtained by adding N,N-diisopropylethylamine and methoxymethyl chloride to a dichloromethanic solution of natural ACG under a nitrogen atmosphere. (3 g), boiled and milled bean (250 g), wheat germ (12.5 g), ascorbic acid (1.5 g), agar agar (12.5 g), methyl p-hydroxybenzoate (1.5 g), formaldehyde (4 mL of a 38 % water solution), and water (500 mL).…”

“…ACG acetylated (OAc) derivatives: squamocin (3 OAc) (11), molvizarin (3 OAc) (12) and motrilin (3 OAc) (13), and their methoxy methylated (MOM) derivatives: squamocin (MOM) (14) and motrilin (MOM) (15) (Figure 2) were synthesized and purified, and then characterized by spectroscopic techniques (Table 1 and Table 2). …”

“…Regarding the insecticidal action of acetogenins, it has been reported that many of these compounds are toxic to Myzus persicae (Homoptera) adults and Leptinotarsa decemlineata (Coleoptera) [15], as well as to nymphs of the German cockroach [2].…”

“…For this purpose, we first carried out the isolation of adjacent and no-adjacent, bis-THF ACGs with OH groups flanking the THF: squamocin (1), molvizarin (2), motrilin (3), rolliniastatin-2 (4), almuñequin (5), cherimolin-1 (6), cherimolin-2 (7), annonacin (8), squamocin D (9), asiminecin (10) (Figure 1) from Annona squamosa. Then, their acetylated (OAc) derivatives: squamocin (3 OAc) (11), molvizarin (3 OAc) (12), motrilin (3 OAc) (13) and methoxy methylated (MOM): squamocin (MOM) (14) and motrilin (MOM) (15), were prepared ( Figure 2). …”