Activity of terpenes derived from essential oils against Sarcoptes scabiei eggs

Nanoemulsion-based plant essential oil formulations: in vitro evaluation of pesticidal activity against ectoparasites in poultry

Ectoparasite infestations significantly impact the health and productivity of poultry. Chemical applications, although common for pest control, lead to pesticide residues and parasite resistance in poultry. Nanoemulsion-based plant essential oil formulations (NEOFs) provide a promising alternative for controlling poultry ectoparasites. This study aimed to assess the efficacy of NEOFs from clove, cinnamon, and turmeric essential oils (EOs) against ectoparasites, Menopon gallinae and Megninia ginglymura, under laboratory conditions. The toxicity and repellent properties of the NEOFs were examined, with the major chemical compounds of the EOs analyzed using chromatography mass spectrometer. Results identified eugenol as the dominant component in clove and cinnamon EOs (84.60 and 75.19%, respectively), while turmerone (68.46%) was the major compound in turmeric EO. NEOFs with clove:cinnamon:turmeric ratios of 4:0:0, 2:2:0, and 2:0:2 had particle size of 20.76 nm, 20.66 nm, and 89.56 nm, respectively, while those based on eugenol and turmerone standards had sizes <21.0 nm. In addition, NEOFs at 0.3% concentration with ratios of 4:0:0 and 2:2:0 achieved full control of both ectoparasites. These formulas demonstrated exceptional potency in exterminating ectoparasites, with LC50 and LC90 at <0.160 and <0.250%, respectively, 6 h after treatments. Furthermore, both NEOFs showed higher repellence responses in M. gallinae compared to M. ginglymura. The toxicities of these NEOFs were comparably effective against both parasites, showing no significant difference compared with chemical insecticide treatment. Therefore, further research will explore the practicality of using clove and cinnamon-derived NEOFs under farm conditions.

A New Herbal Medicine Formulation with Potential Anti-scabies Properties to Treat Demodex and Sarcoptes Parasites

Scabies is considered an external parasite notorious for its high prevalence causing severe and contagious skin lesions in humans and animals worldwide. This study has introduced a medicine to treat dogs infested with scabies (variants of Demodex, Sarcoptes, Psoroptes, Otodectes, etc.). The present study offers a no-side-effect herbal formulation to treat dogs infested with scabies. Unlike oral and injectable medicines, which take the form of an ointment and are topically applied on-site, this medicinal formulation can be easily used without concerns over its side effects or consumption dosages. This medicinal formulation requires no skin rinsing due to its herbal and high skin absorption properties, as recovery may take less than a month with a maximum of two times of application. To carry out the experiment, 25 sick dogs with various breeds and ages suspected of scabies were gathered. Following accurate morphological examinations of all the samples, a deep skin chip of the lesion site was provided, which was examined by a microscope. Then, 13 dogs (Mix, Terrier, Pug, Husky, Spitz) were infested with Demodex scabies and 12 dogs (Pittbull, Mix, Shih Tzu, Terrier, Boxer, Setter) with Sarcoptic scabies. The prepared product was topically administered at a constant 2% dosage to the bodies of all the samples. To prepare the ointment, 1 g of Borax (Na2B4O7·10H2O) was first dissolved in 35 g deionized water and heated to 70°C. Then, 45 g of liquid paraffin (CnH2n+2) was mixed with 1 g of Carvacrol (C10H14O) and 1 g of geranium (C10H18O) and stirred well to become a phase. Later, 17 g of the melted beeswax (C15H31COOC30H61) was added to the liquid paraffin compound. In the end, the aqueous phase was added to the oil phase, and the mixture process immediately began in one direction with a glass stirrer and continued until the product cooled down. Essential oils (EO) was obtained by steam distillation of fresh Thyme and Rose-Acented Geranium in a stainless steel distillation apparatus (alembic) for 3 h. The main components of the essential oils used in the formulation were performed using a Hewlett-Packard GC system interfaced with a mass spectrometer equipped with an HP5-MS capillary column (30 m, 0.32 mm, 0.25 µm film thicknesses). For GC-MS detection, electron ionization with ionization energy of 70 eV was used. To examine the presence of scabies, weekly skin sampling was performed, and the treatment continued until 30 days, when no skin chip of the scabies was noted. The findings revealed that the formulation developed no side effects and removed the daily use, as it could be administered once or twice a week. Also, complete recovery of scabies in all the breeds was found to be less than a month at most. This medicinal formulationcan be easily used without concerns over its side effects or consumption dosages. This study introduced a herbal formulation with effective herbal ingredients without any side effects to treat the sarcoptes and demodex parasites; unlike other chemical compounds, this medicinal formulation has no side effects, while some other formulations could develop side effects.

Natural Products as Mite Control Agents in Animals: A Review

Mites have been a persistent infectious disease affecting both humans and animals since ancient times. In veterinary clinics, the primary approach for treating and managing mite infestations has long been the use of chemical acaricides. However, the widespread use of these chemicals has resulted in significant problems, including drug resistance, drug residues, and environmental pollution, limiting their effectiveness. To address these challenges, researchers have shifted their focus towards natural products that have shown promise both in the laboratory and real-world settings against mite infestations. Natural products have a wide variety of chemical structures and biological activities, including acaricidal properties. This article offers a comprehensive review of the acaricidal capabilities and mechanisms of action of natural products like plant extracts, natural compounds, algae, and microbial metabolites against common animal mites.

Acaricidal and repellent activities of ethanol extracts of nine chinese medicinal herbs against Rhipicephalus microplus (Acari: Ixodidae)

Rhipicephalus microplus is a major threat to the cattle industry worldwide. The intensive use of acaricides and repellents has resulted in drug resistance. Hence, effective and eco-friendly pest control alternatives are urgently needed, especially from natural plant resources. In this study, the acaricidal and repellent activities of nine herbs against the larvae and eggs of R. microplus were evaluated. The results showed that ethanol extracts of star anise (Illicium verum), chaulmoogra (Hydnocarpus anthelmintica), motherwart (Leonurus artemisia), mandarin orange peel (citri reticulatae pericarpium, i.e., peel of Citrus reticulata fruit), and stemona (Stemona sessilifolia) had good contact acaricidal activities of 100, 98, 94, 88 and 86%, respectively, whereas star anise and clove (Syzygium aromaticum) had good fumigant acaricidal activities of 98 and 96%, respectively. The hatching inhibition rate of star anise against R. microplus eggs was 100%. All nine herbs had good real-time repellent rates, but only castor bean and star anise had repellent effects after 48 h (81.3 and 79.6%, respectively). This is the first report of the acaricidal and repellent activities of these medicinal herbs against R. microplus. Ethanol extracts of these herbs might be considered as potential alternatives to chemical acaricides for control of R. microplus.

In vitro toxicity of combination of amitraz and carvacrol on Demodex canis

Background

Canine generalized demodicosis is an inflammatory skin disease, which usually has time-consuming and frustrating treatments.

Aim

The present study aimed to evaluate the acaricidal activity of carvacrol as a green drug and a combination of carvacrol and amitraz on Demodex canis mites and investigate mites' survival lifetime.

Methods

Mite samples were collected from a dog affected by demodicosis and had been diagnosed with deep skin scrapings. The motility of mites was examined by using optical microscopy. Samples were tested with 5% of carvacrol, the combination of Carvacrol 5% + Amitraz 0.05%, Amitraz 0.05% as a positive control, and mineral oil as a negative control. The interval time between the adding the test solutions and the moment the last mite ceased was defined as the survival time in the samples and the killing times of mites in each group were compared with each other.

Results

It was determined that after administration of a 5% concentration of carvacrol, lethal effects were faster than the combination solution of Carvacrol 5% + Amitraz 0.05%, and the survival times in the control groups were longer than in both treatment groups.

Conclusion

Carvacrol, as one of the most important bioactive terpenes, had the most effective in vitro miticidal activity, and it seems that carvacrol alone or in combination with amitraz can be suggested as a possible therapy in the treatment of canine demodicosis.

In Vitro Efficacy of Terpenes from Essential Oils against Sarcoptes scabiei

The mite Sarcoptes scabiei is responsible for the emerging or re-emerging skin disease called scabies in humans and sarcoptic mange in animals. Essential oils represent an appealing alternative strategy for the control of Sarcoptes infections, but the commercial development of essential oils may be hampered by their inconsistency in efficacy due to their varied chemical compositions. In order to address this issue, we assessed the efficacy of six components (carvacrol, eugenol, geraniol, citral, terpinen-4-ol, and linalool) against S. scabiei. At a concentration of 0.5%, carvacrol presented the best miticidal efficacy, with a median lethal time (LT₅₀) value of 6.7 min, followed by eugenol (56.3 min), geraniol (1.8 h), citral (6.1 h), terpinen-4-ol (22.3 h), and linalool (39.9 h). The LC₅₀ values at 30 min for carvacrol, eugenol, and geraniol were 0.24, 0.79, and 0.91%, respectively. In conclusion, carvacrol, eugenol, and geraniol represent potential complementary or alternative agents for S. scabiei infections in humans or animals. Our study provides a scientific basis for the development of scabicidal products based on essential oils.

Essential Oils against Sarcoptes scabiei

Herbal remedia are widely employed in folk medicine, and have been more and more often studied and considered in the treatment of several infections. Sarcoptic mange (scabies, when referring to human patients) is a highly contagious skin disease caused by Sarcoptes scabiei (sarcoptiformes, Sarcoptinae), an astigmatid mite which burrows into the epidermis, actively penetrating the stratum corneum. This parasitosis negatively affects livestock productions and represents a constraint on animal and human health. The treatment relies on permethrine and ivermectine but, since these molecules do not have ovicidal action, more than a single dose should be administered. Toxicity, the possible onset of parasite resistance, the presence of residues in meat and other animal products and environmental contamination are the major constraints. These shortcomings could be reduced by the use of plant extracts that have been in vitro or in vivo checked against these mites, sometimes with promising results. The aim of the present study was to review the literature dealing with the treatment of both scabies and sarcoptic mange by plant-derived agents, notably essential oils.