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BACKGROUND: Previous studies have recorded a high prevalence of intestinal parasites in lettuce (Lactuca sativa L.) and coriander (Coriandrum sativum L.) destined for human consumption. This study determined the prevalence of contamination by intestinal parasites in these two plants sold in two street markets and two supermarkets in the city of Belém, northern Brazil. RESULTS: A total of 200 plant samples were analyzed (100 of each species). The samples were collected randomly between August and October 2018, examined by the spontaneous sedimentation method with two washes, and stored for 24 h. The analysis found that 89% (89/100) of the lettuce samples and 86% (86/100) of the coriander samples were contaminated. Polyparasitism was more frequent in lettuce, but monoparasitism predominated in the coriander. A total of 226 intestinal parasites were found in the lettuce, with a predominance of non-pathogenic parasites in the supermarket samples and more pathogenic parasites in the samples from street markets. In the coriander samples, 172 intestinal parasites were identified, with a predominance of pathogenic parasites in samples from both types of market. In the case of the protozoans, the most prevalent species was Endolimax nana, followed by Blastocystis hominis, in both vegetables. In the helminths, hookworms predominated in the lettuce, and Trichuris trichiura in the coriander. CONCLUSIONS: These results highlight the need for the monitoring of parasite contamination in vegetables destined for human consumption. Public health initiatives should include educational campaigns on the importance of disinfecting vegetables prior to consumption. © 2020 Society of Chemical Industry.

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O parasitismo por nematoides gastrintestinais representa um dos principais problemas para a produção de ovinos e caprinos. Plantas com atividade anti-helmíntica vêm sendo pesquisadas como uma alternativa de controle destes parasitos. O objetivo deste trabalho foi avaliar a atividade anti-helmíntica de óleos essenciais e decoctos de Lantana camara, Tagetes minuta, Coriandrum sativum, Mentha villosa, Alpinia zerumbet e Cymbopogon citratus. Os óleos foram avaliados in vitro através dos testes de eclosão de ovos (TEO) e de desenvolvimento larvar (TDL) com Haemonchus contortus. Os decoctos foram avaliados in vitro usando o TEO e o teste de desembainhamento artificial larvar sobre H. contortus. O óleo essencial de C. citratus (OECc) na dose de 800 mg/kg foi avaliado in vivo utilizando Meriones unguiculatus (gerbis) infectados experimentalmente com H. contortus. Posteriormente, OECc foi submetido ao processo de nanoencapsulamento utilizando como matriz a quitosana, para a formação de uma nanoemulsão contendo o óleo esssencial de C. citratus nanoencapsulado (OECcN). Posteriormente, foi realizada a avaliação da atividade anti-helmíntica in vivo com ovinos naturalmente infectados com nematoides gastrintestinais utilizando as doses de 500 mg/kg do OECc e 450 mg/kg do OECcN. As concentrações efetivas que inibiram em 50% (CE50) a eclosão das larvas foram de 0,9; 0,6 e 0,5 mg/mL para os decoctos de A. zerumbet, T. minuta e M. villosa. Os decoctos inibiram o desembainhamento larvar de H. contortus na concentração de 310μg/mL para A. zerumbet e M. villosa e na concentração de 620μg/mL para T. minuta e L. camara. As CE50 obtidas no TEO e TDL para os óleos essenciais de A. zerumbet, C. sativum, T. minuta e C. citratus foram de 0,9 e 3,8 mg/mL; 0,6 e 2,8 mg/mL; 0,53 e 1,6 mg/mL; 0,14 e 1,9 mg/mL, respectivamente. OECc teve eficácia de 38,5% na redução da carga parasitária de H. contortus em gerbis. No teste in vivo com ovinos, OECc e OECcN apresentaram eficácia de 48,9 e 69,2% na redução da eliminação de ovos de nematoides gastrintestinais nas fezes de ovinos e eficácia de 52,9% e 71,2% sobre redução da carga de H. contortus, respectivamente. O óleo essencial de C. citratus demonstrou eficácia anti-helmíntica a qual foi aumentada após o nanoencapsulamento, no entanto, não foi obtido o nível terapêutico de anti-helmínticos comerciais.

Gastrointestinal parasites represent one of the main problems for sheep and goat production. Plants with anthelmintic activity are being researched as alternative for the control of these parasites. The objective of this work was to evaluate the anthelmintic activity of essential oils and decoctions of Lantana camara, Tagetes minuta, Coriandrum sativum, Mentha villosa, Alpinia zerumbet and Cymbopogon citratus. The oils were evaluated in vitro through egg hatching test (EHT) and larval development test (LDT) against Haemonchus contortus. The decoctions were evaluated in vitro using EHT and artificial exsheathment larval on H. contortus. The C. citratus essential oil (CcEO) in dose of 800 mg/kg was evaluated in vivo using Meriones unguiculatus (gerbils) experimentally infected with H. contortus. Subsequently, CcEO was subjected to the nanoencapsulation process using chitosan as matrix, for the forming a nanoemulsion containing C. citratus essential oil nanoencapsuled (CcEOn). This was followed by the evaluation of anthelmintic activity in vivo with sheep naturally infected with gastrointestinal nematodes using doses of 500 mg/kg of CcEO and 450 mg/kg of CcEOn. The effective concentrations that inhibited 50% (EC50) larvae hatching were 0.9; 0.6 e 0.5 mg/mL for decoctions A. zerumbet, T. minuta and M. villosa. The decoctions were effective in inhibiting exsheathment H. contortus larvae in the concentration of 310μg/mL for A. zerumbet and M. villosa and the concentration of 620μg/mL for T. minuta and L. camara. The EC50 obtained in EHT and LDT for essential oils of A. zerumbet, C. sativum, T. minuta and C. citratus were 0.9 and 3.8 mg/mL; 0.6 and 2.8 mg/mL; 0.53 and 1.6 mg/mL; 0.14 and 1.9 mg/mL, respectively. OECc had efficacy of 38.5% in reducing the H. contortus parasitic load of gerbils. The in vivo test using sheep, CcEO and CcEOn present efficacy of 48.9 and 69.2% in reduction of the elimination of eggs gastrointestinal nematode in the feces of sheep and effectiveness of 52.9% and 71.2% on reduction of H. contortus burden, respectively. The C. citratus essential oil showed anthelmintic efficacy, which was increased after nanoencapsulation, however it was not yet obtained the therapeutic level of commercial anthelmintics.

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