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The present study aimed to evaluate the anthelmintic activity of leaf and bark extracts of Diospyros anisandra collected during different seasons and their major constituents on eggs of Ancylostoma caninum, Haemonchus placei , and cyathostomins. Specifically, the eclosion inhibition of the methanolic extracts of the leaves and bark of D. anisandra collected during the dry and rainy seasons (600–37.5 μg/ml) were evaluated in addition to the fractions, sub-fractions (300–37.5 μg/ml) and active major constituents (150–2.3 μg/ml). The rainy season bark extract had the highest percentage of eclosion inhibition (PEI) against the evaluated nematodes (≥ 90% at 75 μg/ml) along with high ovicidal activity (90.0 to 93.4% at 75 μg/ml). The purification of the rainy season bark extract showed that its biological activity came from the non-polar n -hexane fraction (≥ 93% at 75 μg/ml). The bioguided fractionation pointed to sub-fraction 5 as having the highest anthelmintic activity against the three evaluated genera of nematodes (PEI ≥ 93% at 37.5 μg/ml). Gas chromatography and mass spectrometry revealed that the major constituent in sub-fraction 5 was plumbagin. Upon evaluation, plumbagin was confirmed to be responsible for the anthelmintic activity of D. anisandra , with a PEI ≥ 90% at 2.3 μg/ml on the three evaluated nematodes. Additionally, the compounds betulin and lupeol in the bark of D. anisandra were evaluated but presented low anthelmintic activity (PEI ≤ 5.3% at 2.3 μg/ml). In conclusion, the rainy season bark extract of D. anisandra exerts a high ovicidal activity against the eggs of the three studied nematodes. Plumbagin is the active compound responsible for this activity and represents a potential alternative for the control of different genera of gastrointestinal nematodes given the current scenario of anthelmintic resistance.

The aim of the study was to evaluate methanolic extracts from the stem and leaves of Petiveria alliacea, bark of Bursera simaruba and Casearia corymbosa collected in two seasons on eggs of Ancylostoma caninum, Haemonchus placei and cyathostomin. The egg hatch inhibition assay was used at concentrations of 3600, 2400, 1200, 600 and 300 µg/ml. The extracts with high activity were also evaluated at 300, 150, 75 and 37.5 µg/ml. Lethal concentrations were determined at 50% (LC 50) and 99% (LC 99), as well as the confidence intervals at 95%. Differences (p < 0.05) between control and evaluated concentrations were analyzed. The P. alliacea extract collected in the rainy season (CRS) showed a percentage of egg hatch inhibition (PEHI) ≥ 91.6% from 150 µg/ml, and ovicidal effect (≥ 90.1%) from 150 µg/ml with stem and 300 µg/ml with leaves in both parameters on the three genera of gastrointestinal nematodes evaluated. The B. simaruba extract CRS (3600 µg/ml) showed a PEHI of 95.4, 25.4 and 56.3% against A. caninum, H. placei and cyathostomins, respectively. While the C. corymbosa extract at the same season and concentration had the highest PEHI of 55.1, 74.0 and 56.4% against the three nematodes, respectively. The effect of B. simaruba and C. corymbosa on the eggs was the failure of the L 1 larvae to hatch (23.7-95.1% and 30.4-60.8%, respectively, at 3600 µg/ml). Additionally, it was observed that C. corymbosa extract caused morphological damage to the larvae that hatched (100% from 1200 µg/ml). Extracts from the stem of P. alliacea CRS showed the lowest LC 50 (33.3, 78.9 y 68.6 µg/ml) and LC 99 (79.5, 178.0 and 277.4 µg/ml) against A. caninum, H. placei and cyathostomins, respectively. It is concluded that the methanolic extracts of P. alliacea, B. simaruba and C. corymbosa collected in rainy season showed the highest anthelmintic activity on eggs of A. caninum, H. placei and cyathostomins. The stem of P. alliacea CRS has high ovicidal activity on the three nematodes, representing a potential alternative control with a broad spectrum against the main nematodes of domestic animals.

<p><strong>Background.</strong> In tropical and subtropical regions of the world, ticks and nematodes negatively affect the health and welfare of animals, the search for natural alternatives for parasite control is necessary to reduce resistance and dependence to antiparasitics. <strong>Objective</strong>. To present the main findings on the acaricidal and anthelmintic activity of <em>Petiveria alliacea</em> against ticks and nematodes of domestic animals. <strong>Methodology.</strong> Scientific articles were compiled from studies carried out by the animal health academic research group of the Faculty of Veterinary Medicine and Zootechnics of the Autonomous University of Yucatán. The review focused on the use of methanolic extracts and compounds from <em>P. alliacea</em> against larvae and adults of <em>Rhipicephalus microplus</em>, as well as against nematodes of the order strongylida such as <em>Ancylostoma</em> spp., <em>Haemonchus</em> spp. and cyathostomids. <strong>Main findings. </strong>Research on the biological activity of <em>P. alliacea</em> extracts have shown their acaricidal and anthelmintic potential. Extracts of <em>P. alliacea</em> showed high mortality rates on larvae and adult females of <em>R. microplus</em> resistant to ixodicides, as well as a decrease in reproductive parameters (inhibition of oviposition and hatching inhibition). The acaricidal activity of <em>P. alliacea</em> is attributed to the presence of the sulfur compounds dibenzyl trisulfide and dibenzyl disulfide, which cause histological damage to the reproductive system of adult females, affecting the oogenesis process. Additionally, <em>P. alliacea</em> demonstrated broad spectrum anthelmintic activity, exhibiting high percentages of hatching inhibition on <em>A. caninum</em>, <em>H. placei</em> and cyathostomid eggs. A difference was also observed in the acaricidal and anthelmintic activity depending on the part of the plant and the time of collection. <strong>Implications.</strong> Further studies are needed to identify anthelmintic active compounds of <em>P. alliacea</em>, elucidate the mechanisms of action of these compounds, and test both acaricidal and anthelmintic compounds in <em>in vivo</em> studies. <strong>Conclusions</strong>. The extracts of <em>P. alliacea</em> and its compounds showed high acaricidal and anthelmintic activity against <em>R. microplus</em> ticks and nematodes of the order strongylida of domestic animals, due to this, they are a potential control alternative for broad spectrum.</p>