Active components from plants are an alternative therapy to parasite control, addressing the widespread multidrug resistance populations. Linalyl acetate (LA), an ester abundantly found in plants of the genus Lavandula, was tested in vitro against third-stage larvae (L3) of Haemonchus spp. and Trichostrongylus spp. using the larval migration test at 0.89, 2.24, 4.47, 8.95, 17.9, 35.8, 71.6, and 143.2 mg/ml. After an initial incubation of 18 h, the total content of each tube was transferred to a 24-well plate that allowed active L3 to migrate through a nylon mesh (second incubation). Although LA exhibited 100% efficacy in reducing larval migration at 8.95 and 17.9 mg/ml, it showed reduced activity (5%) at 143.2 mg/ml. The data revealed a hormetic biphasic response characterised by an inverted U-shaped concentration-response curve. While hormesis has been previously documented in insecticidal and allelopathic contexts, this study reports the occurrence of hormesis induced by a phytochemical component against two species of nematodes for the first time. This distinctive stimulation-and-inhibition effect should be considered when selecting new compounds for preclinical testing.

There is a substantial use of Complementary and Alternative Medicine (CAM) among both the general population and psychiatric patients, with only a minority of these users disclosing this information to their healthcare providers, including physicians and psychiatrists. This widespread use of CAM can impact positively or negatively on the clinical outcomes of psychiatric patients, and it is often done along with conventional medicines. Among CAM, phytotherapy has a major clinical relevance due to the introduction of potential adverse effects and drug interactions. Thus, the psychiatrist must learn about phytotherapy and stay up-to-date with solid scientific knowledge about phytotherapeutics/herbal medicines to ensure optimal outcomes for their patients. Furthermore, questions about herbal medicines should be routinely asked to psychiatric patients. Finally, scientifically sound research must be conducted on this subject.

This work aimed to evaluate the in vitro anthelmintic effect of carvone nanoemulsions on Haemonchus contortus. Three R-carvone nanoemulsions were prepared: uncoated R-carvone nanoemulsions homogenized in a sonicator (UNAlg-son) and homogenized in an ultrahomogenizer (UNAlg-ultra) and sodium alginate-coated R-carvone (CNAlg-ultra). The physicochemical characterizations of the nanoemulsions were carried out. The anthelmintic activity was evaluated using egg hatch test (EHT), larval development test (LDT) and adult worm motility test (AWMT). Changes in cuticle induced in adult H. contortus were evaluated by scanning electron microscopy (SEM). The results were subjected to analysis of variance and compared using the Tukey test (P < 0.05). The effective concentration to inhibit 50% (EC50) of egg hatching and larval development was calculated. The particle sizes were 281.1 nm (UNAlg-son), 152.7 nm (UNAlg-ultra) and 557.8 nm (CNAlg-ultra), and the zeta potentials were −15 mV (UNAlg-son), −10.8 mV (UNAlg-ultra) and −24.2 mV (CNAlg-ultra). The encapsulation efficiency was 99.84 ± 0.01%. SEM of the nanoemulsions showed an increase in size. In EHT, the EC50 values of UNAlg-son, UNAlg-ultra and CNAlg-ultra were 0.19, 0.02 and 0.17 mg mL−1, respectively. In LDT, they were 0.29, 0.31 and 0.95 mg mL−1 for UNAlg-son, UNAlg-ultra and CNAlg-ultra, respectively. The adult motility inhibition was 100% after 12 h of exposure to UNAlg-ultra and CNAlg-ultra, while for UNAlg-son, it was 79.16%. SEM showed changes in the buccal capsule and cuticular damage. It was concluded that R-carvone nanoemulsions showed antiparasitic action demonstrating promise for the control of infections caused by gastrointestinal nematodes in small ruminants.

Cystic echinococcosis is a zoonotic disease caused by the larval stage of the parasite Echinococcus granulosus sensu lato. The available anti-parasitic treatment is mostly limited to a continuous administration of albendazole. However, due to its numerous side-effects and efficacy of around 50%, there is a need to find new drugs to improve the treatment for this disease. In the current study, the in vitro and in vivo efficacy of a Stevia multiaristata extract against E. granulosus sensu stricto (s.s.) was demonstrated. Stevia multiaristata extract (100 and 50 μg mL−1) caused a quick viability decrease on protoscoleces which was consistent with the observed tegumental alterations. Loss of turgidity was detected in 95 ± 3.4% of cysts incubated with S. multiaristata extract during 2 days (100 μg mL−1) and the collapse of the germinal layer was observed in 60 ± 9.3% of cysts treated with 100 μg mL−1 of the S. multiaristata extract during 4 days. The half maximal effective concentration value was 69.6 μg mL−1 and the selectivity index for E. granulosus s.s. cysts was 1.9. In this clinical efficacy study, the treatment of infected mice with the S. multiaristata extract (50 mg kg−1) caused a significant decrease in the weight of the cysts compared with the control group. These results coincided with the tissue damage observed in the cysts at the ultrastructural level. In conclusion, we observed high protoscolicidal and cysticidal effects, and significant reduction in the weight of the cysts in experimentally infected mice following treatment with the S. multiaristata extract.

This systematic review investigated the evidence for the therapeutic potential of essential oils (EOs) against Leishmania amazonensis. We searched available scientific publications from 2005 to 2019 in the PubMed and Web of Science electronic databases, according to PRISMA statement. The search strategy utilized descriptors and free terms. The EOs effect of 35 species of plants identified in this systematic review study, 45.7% had half of the maximal inhibitory concentration (IC50) 10 < IC50 ⩽ 50 μg mL−1 and 14.3% had a 10 < IC50μg mL−1 for promastigote forms of L. amazonensis. EOs from Cymbopogon citratus species had the lowest IC50 (1.7 μg mL−1). Among the plant species analyzed for activity against intracellular amastigote forms of L. amazonensis, 39.4% had an IC50 10 < IC50 ⩽ 50 μg mL−1, and 33.3% had an IC50 10 < IC50μg mL−1. Aloysia gratissima EO showed the lowest IC50 (0.16 μg mL−1) for intracellular amastigotes. EOs of Chenopodium ambrosioides, Copaifera martii and Carapa guianensis, administered by the oral route, were effective in reducing parasitic load and lesion volume in L. amazonensis-infected BALB/c mice. EOs of Bixa orellana and C. ambrosioides were effective when administered intraperitoneally. Most of the studies analyzed in vitro and in vivo for the risk of bias showed moderate methodological quality. These results indicate a stimulus for the development of new phytotherapy drugs for leishmaniasis treatment.

The number of cattle operations which manage their livestock as certified organic or as natural is constantly increasing. Common conditions that practitioners often see have bacterial, viral or parasite etiologies. With restrictions on treatments allowed, either by the United States Department of Agriculture (USDA) Certified Organic program or by other niche programs, it would help practitioners to know what is allowable to use and how to approach cases in these settings. This presentation aims to provide veterinarians with an awareness of animal health care when working with organic/natural producers and alternative therapies that are understandable to medically trained professionals.

In the last 50 years science has provided new perspectives on the ancient art of herbal medicine. The present article discusses ways in which the evidence base for the professional use of 'Western' herbal medicine, as therapy to treat disease, known as phytotherapy, can be strengthened and developed. The evidence base for phytotherapy is small and lags behind that for the nutritional sciences, mainly because phytochemicals are ingested as complex mixtures that are incompletely characterised and have only relatively recently been subject to scientific scrutiny. While some methodologies developed for the nutritional sciences can inform phytotherapy research, opportunities for observational studies are more limited, although greater use could be made of patient case notes. Randomised clinical trials of single-herb interventions are relatively easy to undertake and increasing numbers of such studies are being published. Indeed, enough data are available on three herbs (ginkgo (Ginkgo biloba), St John's wort (Hypericum perforatum) and saw palmetto (Serenoa repens)) for meta-analyses to have been undertaken. However, phytotherapy is holistic therapy, using lifestyle advice, nutrition and individually-prescribed mixtures of herbs aimed at reinstating homeostasis. While clinical experience shows that this approach is applicable to a wide range of conditions, including chronic disease, evidence of its efficacy is scarce. Strategies for investigating the full holistic approach of phytotherapy and its main elements are discussed and illustrated through the author's studies at the University of Reading.