The combined action of phytolarvicides for the control of dengue fever vector, Aedes aegypti

Abstract

Amongst other botanical sources, Annona muricata L., Annonaceae, seeds and Piper nigrum L., Piperaceae, fruits are particularly enriched with acetogenins and piperine-related amides, respectively. These crude ethanolic extracts are potent bioactives that can kill Aedes aegypti larvae (dengue fever mosquito). A. muricata displayed a 93.48 μg/mL LC50 and P. nigrum an 1.84 μg/mL LC50. An uncommon pharmacognostical/toxicological approach was used, namely different combinations of both extracts to achieve an improved lethal effect on the larvae. The independence test (χ²) was utilized to evaluate the combination of the two crude extracts. All of the tested combinations behaved synergistically and these novel results were attributed to the completely different biochemical mechanisms of the differentiated chemical substances that were present in the two botanical sources. Besides the two above selected plants, Melia azedarach L., Meliaceae, Origanum vulgare L., Lamiaceae, and Ilex paraguariensis A. St.-Hil., Aquifoliaceae, in order of decreasing toxicity, may also be sought as potential extracts for the sake of synergic combinations.

Potential of <em>Annona muricata</em> L. seed oil: phytochemical and nutritional characterization associated with non-toxicity

“…Alkaloids were not found in AmSO or AmPtO (data not shown). The principal spot was present in all the samples analyzed in the present study, mainly in the methanol fraction, and may be associated to the presence of annonacin, considering that acetogenin is the major compound in A. muricata seeds (Moghadamtousi et al, 2015;Grzybowski et al, 2012;Champy et al, 2002). The strong absorption at 1745 cm −1 (lactone C=O), a strong aliphatic C-H absorption below 3000 cm −1 in the IR spectrum suggested the presence of an unsaturated lactone moiety in an annonacin-type acetogenin (Champy et al, 2002).…”

“…The thin layer chromatographic profiles were made with AmSO, AmPtO and their fractions obtained by SPE extraction according to Grzybowski et al, (2012). Chromatoplates were made with hexane: chloroform: nitroethane: ethyl acetate: acetone: methanol: acetonitrile: water (12:2:4:4:1:2:1.6:0.1, v/v) as mobile phase.…”

Rooting responses of black pepper (Piper nigrum cv. Bragantina) as affected by chemical, physical and microbiological properties of substrates and auxin

“…The black pepper (P. nigrum L.) is a perennial woody vine species largely traded worlwide as condiment, medicinal purposes, and other uses such as as phytolarvicides in control of dengue insect (Aedes aegypti) (Simas et al, 2007;Grzybowski et al, 2012). Despite the high number of catalogued varieties (around 51) by Mathew et al (2001) in India, in Brazil, the production relies on the Bragantina variety, mainly in pepper nurseries of northern Espírito Santo state.…”

Active metabolites of the genus Piper against Aedes aegypti: natural alternative sources for dengue vector control

“…nigrum extract combination at 9:1. The authors suggest that the synergism of this combination was responsible for the morphological effects that took place in the larvae's bodies that lead to their mortality (Grzybowski et al 2012). Simas et al (2007) reported on the fractionation of P. nigrum ethanol extract.…”