In vitro ovicidal activity of two chemotypes of the yarrow (Achillea millefolium L.) essential oil against sheep gastrointestinal nematodes

Abstract

The economic losses caused by gastrointestinal nematodes of small ruminants are increasing today due to the development of anthelmintic resistance. Therefore, researchers from different parts of the world are searching for new, alternative strategies to control these parasites. As a valuable natural resource, medicinal plants and their products have emerged as a viable option. The aim of this study was to evaluate in vitro ovicidal activity of two chemotypes of the yarrow (Achillea millefolium L.) essential oil against sheep gastrointestinal nematodes. For this purpose, nematode eggs were collected from naturally infected sheep of two farms located in Southern Italy to perform the egg hatch test. In both farms, the coproculture examination identified the presence of four genera of sheep GINs: Haemonchus, Trichostrongylus, Teladorsagia and Chabertia. Main components of the yarrow essential oil identified by GC-MS analysis were 1,8-cineole (41.69%), camphor (8.37%) and trans-chrysanthenyl acetate (4.90) for the type 1 and β-pinene (28.53%), β-caryophyllene (18.71%) and 1,8-cineole (11.69%) for the type 2. In vitro ovicidal activity was evaluated at six different concentrations (50, 12.5, 3.125, 0.781, 0.195 and 0.049 mg/mL), whereby the inhibitory effect of the essential oil (Achillea millefolium L.) on egg hatchability varied from 46.5-99.5% (type 1) and 69.6-97.25% (type 2) and all concentrations tested showed a significantly higher efficacy compared to the negative control (p<0.0001). Furthermore, the inhibitory effect on egg hatching was similar (p>0.05) to the positive control (98.0%) at concentrations of 50 mg/mL (99.5%), 12.5 mg/mL (98.0%) and 3.125 (95.25%) of the type 1, and at concentrations of 50 mg/mL (97.25%) and 12.5 mg/mL (90.0%) of the type 2. The obtained results suggested that the A. millefolium essential oil has high anthelmintic potential, especially azulene-free chemotype rich in 1,8-cineole and camphor, which requires confirmation in further in vivo studies.

Anthelmintic Properties of Essential Oils to Control Gastrointestinal Nematodes in Sheep—In Vitro and In Vivo Studies

“…The lack of studies is especially noticable in relation to in vivo testing [18], whereby the results of trials conducted so far, including the present study, show the inferior activity of EOs compared to synthetic drugs [40]. However, finding an appropriate formulation (plant species, chemical composition, dose and method of application) is not a simple task, thus requiring a larger number of studies and works [60][61][62], whereby the comparison between results obtained for different EO samples is also important for the selection. Finally, novel encapsulation methods offer the possibility of overcoming these problems and achieving appropriate efficiency, as discussed earlier.…”

Anti-helmintic Activity of Myrtus communis L. Fruit Ethanol Extract on Nematodes of Caenorhabditis elegans and The Determination of Possible Active Ingredients

“…Compounds such as beta-seline, palmitic acid, 9,12-Octadecadienoic acid, and camphene, which we determined as a result of GC-MS analysis of Myrtus communis L. fruit ethanol extract, were found in many plants have anthelmintic effects [28][29][30][31][32][33][34].…”

Herb and Flowers of Achillea millefolium subsp. millefolium L.: Structure and Histochemistry of Secretory Tissues and Phytochemistry of Essential Oils

“…millefolium formed dense corymbose clusters at shoot apices (Figure 1a) and consisted of small capitula (Figure 1b). In the peripheral part of the capitula, there were sparse (5) and most often white ray flowers, while the central part of the inflorescence was occupied by disc flowers (8)(9)(10)(11)(12)(13)(14)(15)(16)(17)(18) characterised by a whitish 5-toothed corolla (Figure 1b). A characteristic trait of the epidermis of the ray and disc flower petals was the presence of conical cells (papillae) on the adaxial surface of the teeth (Figure 1h,i).…”

“…One of the oldest known botanicals used by humans is Achillea millefolium L. (yarrow), a cosmopolitan perennial growing in the temperate climate of Eurasia, America Northern, and Australia [6,7]. Achillea millefolium represents a highly polymorphic group of closely related species, subspecies, microspecies, and hybrids, which differ in the ploidy level, morphology, and chemical composition [8][9][10]. There are five most common subspecies of A. millefolium: subsp.…”