This study assessed the anthelmintic activity of plant-derived compounds against gastrointestinal nematodes of goats using the egg hatch and larval motility assays. The compounds tested were saponins (digitonin and aescin) and their respective sapogenins (aglycones), hecogenin acetate and flavonoids (catechin, hesperidin, isocordoin and a mixture of isocordoin and cordoin). Additionally, cytotoxicity of active substances was analysed on Vero cell through 3-4,5-dimethylthiazol-2-yl,2,5diphenyltetrazolium bromide (MTT) and propidium iodide (PI) tests. Significant reduction on the egg hatching (P 90%). Nevertheless, higher cytotoxicity was observed in the MTT assay, with IC50 of 0.20 mg mL-1 (aescin) and 0.0074 mg mL-1 (digitonin). Aescin and digitonin have a pronounced in vitro anthelmintic effect and the glycone portion of these saponins plays an important role in this activity.

It was evaluated the anthelmintic activity of Agave sisalana (sisal) juice against gastrointestinal nematodes and its potential toxic effects in goats. In vitro tests showed more than 95% reduction in larval counts of the genus Haemonchus spp. at concentrations between 86.5 and 146.3 mg.mL -1. In vivo the percent reduction of larvae of the fourth (L4) and fifth (L5) stages of Haemonchus, Oesophagostomum and Trichostrongylus was less than 95% in groups GI and GII, and between 80 and 90% in group GIII. A. sisalana juice at the concentrations tested in vitro was effective against gastrointestinal nematodes in goats; however, its anthelmintic efficacy was reduced when administered to animals.Keywords: Agave sisalana, anthelmintic, goats, nematodes, sisal. ResumoFoi avaliada a atividade anti-helmíntica do suco de Agave sisalana (sisal) contra nematódeos gastrintestinais e possíveis efeitos tóxicos em caprinos. Nos testes in vitro, encontrou-se redução superior a 95% na contagem de larvas do gênero Haemonchus spp. nas concentrações entre 86,5 e 146,3 mg.mL -1 . In vivo, o percentual de redução de larvas de quarto (L4) e quinto (L5) estágios de Haemonchus, Oesophagostomum e Trichostrongylus foi inferior a 95% para o GI e GII, e entre 80 e 90% para o GIII. O suco de A. sisalana nas concentrações testadas in vitro foi efetivo contra nematódeos gastrintestinais de caprinos, apresentando, no entanto, reduzida eficácia anti-helmíntica quando administrado nos animais.Palavras-chave: Agave sisalana, anti-helmíntico, caprinos, nematódeos, sisal.The goat industry is a livestock activity of great socioeconomic importance in Northeastern Brazil, but its operation has been limited by frequent gastrointestinal nematode infections (GNI) and inappropriate drug use, which has led to resistance of these parasites to common anthelmintics.Given the interest in the use of waste liquid of A. sisalana and lack of scientific evidence regarding its potential anthelmintic activity, the objective of the present study was to evaluate the effect of A. sisalana juice against gastrointestinal nematodes and its potential toxic effects in goats.Agave sisalana plants were collected in Valente, Bahia. They were identified by botanists and voucher specimens (No. 838) were deposited in the herbarium of the Universidade Estadual de Feira de Santana.A. sisalana pulp and juice were collected through mechanical defibration of the leaves. The juice was obtained after filtration three times in filter paper and stored at 4 °C for use in in vivo tests. For in vitro tests, the juice was dried and frozen. Five concentrations were used in this study : 146.3, 112.5, 86.5, 66.5, 51.1 and 39.3 mg.mL -1 , which were tested in triplicate. To validate the results, the same experiment was repeated three times.Larval cultures (UENO; GONÇALVES, 1998) consisted of 2 g of feces, 2 g of sawdust, and 2 mL of juice. Positive and negative controls were treated with doramectin (0.0625 mg.mL -1 ) and distilled water, respectively.Twenty-four racially undefined goats b...

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Abstract We investigated the in vitro acaricide activity of the methanolic extract (ME) and alkaloid-rich fraction (AF) of Prosopis juliflora on Rhipicephalus microplus and correlated this effect with acetylcholinesterase (AChE) inhibition. The acaricide activity was evaluated using adult and larval immersion tests. Also, we studied the possible interaction mechanism of the major alkaloids present in this fraction via molecular docking at the active site of R. microplus AChE1 (RmAChE1). Higher reproductive inhibitory activity of the AF was recorded, with effective concentration (EC50) four times lower than that of the ME (31.6 versus 121 mg/mL). The AF caused mortality of tick larvae, with lethal concentration 50% (LC50) of 13.8 mg/mL. Both ME and AF were seen to have anticholinesterase activity on AChE of R. microplus larvae, while AF was more active with half-maximal inhibitory concentration (IC50) of 0.041 mg/mL. The LC-MS/MS analyses on the AF led to identification of three alkaloids: prosopine (1), juliprosinine (2) and juliprosopine (3). The molecular docking studies revealed that these alkaloids had interactions at the active site of the RmAChE1, mainly relating to hydrogen bonds and cation-pi interactions. We concluded that the alkaloids of P. juliflora showed acaricide activity on R. microplus and acted through an anticholinesterase mechanism.