Acaricidal efficacy of Calotropis procera (Asclepiadaceae) and Taraxacum officinale (Asteraceae) against Rhipicephalus microplus from Mardan, Pakistan

Evaluation of the in vitro acaricidal effect of five organic compounds on the cattle fever tick Rhipicephalus (Boophilus) microplus (Acari: Ixodidae)

The cattle fever tick, Rhipicephalus (Boophilus) microplus, is the most economically important tick worldwide. Infestations with this tick can lead to direct damage and cattle mortality due to the transmission of potentially deadly pathogens. Management of this tick species has been focused on the use of synthetical acaricides; however, the emergence of acaricide resistance to single or multiple active ingredients has resulted in a need for novel acaricide compounds. Among potential avenues for the discovery of novel acaricides are plant-derived compounds. The efficacy of five organic compounds (nootkatone, Stop the Bites®, BioUD®, lavender oil, and cedarwood oil) was evaluated using larval immersion tests (LITs), repellency assays, and adult immersion tests (AITs). The results from the LITs indicate that three of the organic compounds (NootkaShield™, Stop the Bites, BioUD) led to significant mortalities at low concentrations (0.2, 0.02, and 0.08%, respectively). By comparison, lavender and cedar oil led to around 90% mortality at 10 and 1% concentrations, respectively. Similarly, NootkaShield, Stop the Bites, and BioUD had strong repellent properties with over 90% repellency at the two highest concentrations tested. Using the FAO 2004 guidelines, we evaluated the effectiveness of these organic compounds at reducing the fecundity of R. (B.) microplus and show that Nootkatone, Stop the Bites, and BioUD may significantly decrease tick populations (Drummond's index > 90% at concentrations of 5%), highlighting their potential as alternatives to synthetic acaricides for the control of cattle fever ticks.

Efficiency of Multiple Extraction Solvents on Antioxidant, Cytotoxic, and Phytotoxic Potential of Taraxacum officinale (L.) Weber ex F.H. Wigg. from Poonch Valley, Azad Kashmir, Pakistan

Background

Different parts of Taraxacum officinale (L.) were used in traditional medicine in various parts of the world for the treatment of health problems, and they possess significant biological activities. The present study aimed to estimate phytochemical and biological activities of T. officinale using different extraction solvents.

Methods

Methanolic, acetone, and n-hexane extracts of selected species were prepared, and ten secondary metabolites were examined using standard protocols. The antioxidant activity was performed using three in vitro methods, namely, DPPH assay, total reducing power (TRP) assay, and total antioxidant capacity (TAC). Toxicological analysis was done using the brine shrimp cytotoxic assay and radish seed phytotoxic assay.

Results

The T. officinale methanolic extract showed the highest phenolic (178.27 ± 17.17 mg/GAE/g) and flavonoid (18.50 ± 1.64 mg QE/g) contents. Similarly, the methanolic extract also revealed the highest DPPH activity (32.80 ± 9.66 IC₅₀), reducing potential (0.53 ± 0.02 mg/g), and TAC (19.42 ± 0.97 mg/g) as compared to the acetone and n-hexane extracts. The Pearson correlation analysis confirmed a strong positive correlation (r > 0.9) between total phenolic content (TPC), total flavonoid content (TFC), and all antioxidant assays. Furthermore, a heat map displayed the methanolic extract (red color) as a valuable source of phytochemicals and antioxidant agents. Moreover, the T. officinale methanolic extract also showed the highest (7.12 ppm) cytotoxic potential whereas both methanolic and acetone extracts were revealed as moderate phytotoxic agents when compared with the standard.

Conclusion

The T. officinale methanolic extract exhibited comparatively notable phytochemicals that are actively involved in antioxidant activities and possess toxicological properties. This upholds the folkloric use of T. officinale as a possible source to develop natural plant-based drugs. Further investigations to isolate bioactive compounds and elements and on their safety need to be conducted.

Gastroprotective Effects of the Aqueous Extract from Taraxacum officinale in Rats Using Ultrasound, Histology, and Biochemical Analysis

Taraxacum officinale F.H. Wigg. belonging to the family Asteraceae is an edible medicinal plant distributed worldwide. This study aimed to determine the gastroprotective effects of aqueous extract of T. officinale (AETo) in rats using ultrasound, histological, and biochemical analyses. In this study, gastric ulceration was induced by ethanol or piroxicam. Rats were then treated with AETo (3, 30, or 300 mg/kg). The area and histological appearance of gastric ulcers were quantified, and histochemical analysis was performed. The activity of AETo on inflammatory and oxidative stress markers was assessed in the ulcerated tissue. In addition, we investigated the thickness of the gastric wall using the ultrasound technique. Moreover, chemical analyses of AETo were performed. In rats with ethanol- or piroxicam-induced ulcers, AETo reduced the ulceration area, elevated mucin level, and the gastroprotective effect was confirmed by histological analysis. The gastroprotective effect was accompanied by increased activities of SOD, CAT, and GST, as well as an increase in GSH level and reduction in MPO activity. Furthermore, AETo reduced the thickness of the gastric wall in rats. Phytochemical analysis of AETo indicated phenolic acids and flavonoids as the main active compounds. In conclusion, the gastroprotective effect of AETo involves reduction in oxidative stress and inflammatory injury and increase in mucin content. This study advances in the elucidation of mechanisms of gastric protection of T. officinale, contributes to the prospection of new molecules gastroprotective, and proposes the ultrasonographic analyses as a new gastroprotective assessment tool in preclinical studies.

Ticks and tick-borne diseases of bovines in a smallholder livestock context: The Pakistani example

Ticks and tick-borne diseases (TTBDs) substantially affect the health and production of ruminants, particularly in resource-poor, small-scale farming systems worldwide. However, to date, there has been no critical appraisal of the current state of knowledge of TTBDs in such farming systems. In this article, we systematically reviewed the situation in Pakistan-as an example of a country that is highly reliant on agriculture to sustain its economy, particularly smallholder livestock farms, which are continually faced with challenges associated with TTBDs. The main aims of this review were to gain improved insights into the current status of TTBDs in small-scale farming systems, and to identify knowledge gaps, through the systematic evaluation of published literature on this topic from Pakistan, and to recommend future research directions. We searched publicly available literature from three databases (i.e. Web of Science, Google Scholar, and PubMed) on bovine TTBDs in Pakistan. Of 11,224 published studies identified, 185 were eligible for inclusion; these studies were published between August 1947 and June 2021. A critical analysis of these 185 studies revealed that the diagnosis of ticks and tick-borne pathogens (TBPs) in Pakistan has been based largely on the use of traditional methods (i.e. 'morpho-taxonomy'). At least 54 species of tick have been recorded, most of which belong to the genera Haemaphysalis, Hyalomma and Rhipicephalus. The prevalence of ticks was higher, particularly in young, exotic and crossbred female cattle, during the summer season. Major TBPs include species of Anaplasma, Babesia and Theileria, with prevalences being higher in cattle than buffaloes. Additionally, pathogens of zoonotic potential, including species of Anaplasma, Borrelia, the Crimean-Congo haemorrhagic fever virus, Coxiella, Ehrlichia and Rickettsia, have been recorded in both tick and bovine populations. Information on risk factors, spatial-temporal distribution, genetic diversity, and control of ticks and TBPs is limited, the vector potential of ticks and the distribution patterns of ticks and TBPs in relation to climate remains largely unexplored. Future research should focus on addressing these knowledge gaps and the key challenges of poverty, food security and disease outbreaks in a small-scale livestock farming context in order to provide sustainable, environment-friendly control measures for TTBDs.

Acaricidal activity of the hexanic and hydroethanolic extracts of three medicinal plants against southern cattle tick Rhipicephalus (Boophilus) microplus (Acari: Ixodidae)

The southern cattle tick Rhipicephalus microplus is a major problem for the cattle industry in tropical and subtropical areas worldwide. Chemical products are commonly applied to control it; however, their indiscriminate use has resulted in the appearance of resistant lineages. In the last decades, plants have been used as an alternative to conventional acaricidal drugs, as several plant compounds repel activity, decrease the reproductive potential and reduce the survival rate of ticks. For this reason, the in vitro efficacy of hexanic and hydroalcoholic extracts of Randia aculeata, Moringa oleifera and Carica papaya were evaluated against the larvae and engorged females of R. microplus. Larval packet tests and adult immersion tests were performed with seven concentrations of each of the extracts. The extracts obtained with hydroethanolic solution (polar solvent) exhibited a higher acaricidal activity than extracts prepared with n-hexane (non-polar solvent). Hydroethanolic extracts of R. aculeata seed and shell showed the highest larvicidal activity against R. microplus (100 and 91% mortality, respectively) at a concentration of 100 mg/mL. Randia aculeata (seed and shell), M. oleifera and C. papaya treatments at the same concentration (100 mg/mL) also resulted in adult mortality of 85, 75, 66 and 55%, respectively. The adult immersion test showed that hydroethanolic extracts derived from R. aculeata seed significantly reduced the index of egg laying and increased the percentage inhibition of oviposition of female ticks at a concentration of 100 mg/mL. These results indicate that the tested extracts exhibit acaricidal activity and could be considered as potential agents for the development of alternative natural acaricides against R. microplus.

An Overview of the Characteristics and Potential of Calotropis procera From Botanical, Ecological, and Economic Perspectives

Calotropis procera (Aiton) Dryand. (commonly known as the apple of sodom, calotrope, and giant milkweed) is an evergreen, perennial shrub of the family Apocynaceae, mainly found in arid and semi-arid regions. It is a multipurpose plant, which can be utilized for medicine, fodder, and fuel purposes, timber and fiber production, phytoremediation, and synthesis of nanoparticles. It has been widely used in traditional medicinal systems across North Africa, Middle East Asia, and South-East Asia. At present, it is being extensively explored for its potential pharmacological applications. Several reports also suggest its prospects in the food, textile, and paper industries. Besides, C. procera has also been acknowledged as an ornamental species. High pharmacological potential and socio-economic value have led to the pantropical introduction of the plant. Morpho-physiological adaptations and the ability to tolerate various abiotic stresses enabled its naturalization beyond the introduced areas. Now, it is recognized as an obnoxious environmental weed in several parts of the world. Its unnatural expansion has been witnessed in the regions of South America, the Caribbean Islands, Australia, the Hawaiian Islands, Mexico, Seychelles, and several Pacific Islands. In Australia, nearly 3.7 million hectares of drier areas, including rangelands and Savannahs, have been invaded by the plant. In this review, multiple aspects of C. procera have been discussed including its general characteristics, current and potential uses, and invasive tendencies. The objectives of this review are a) to compile the information available in the literature on C. procera, to make it accessible for future research, b) to enlist together its potential applications being investigated in different fields, and c) to acknowledge C. procera as an emerging invasive species of arid and semi-arid regions.

Botanical acaricides and repellents in tick control: current status and future directions

Ticks are obligate blood-sucking ectoparasites and notorious as vectors of a great diversity of, in many instances, zoonotic pathogens which can cause considerable damage to animal and human health. The most commonly used approach for the control of ticks is the application of synthetic acaricides. However, the negative impacts of synthetic acaricides on the treated animals and the environment, in addition to its documented role in the development of resistance has led to the search for safer and more environmentally friendly alternative methods without compromising efficacy. An emerging promising approach for the control of ticks which has attracted much attention in recent years is the use of botanicals. Indeed, botanicals have been widely reported to show diverse effects and great potential as tick repellent and control. Although several excellent reviews have previously focused on this topic, studies on the exploration and application of botanicals to control ticks have expanded rapidly. Herein, we provide an update on the current understanding and status of botanical acaricides and repellents in tick control using recently published articles between 2017 and 2019. We also discuss the challenges and future directions in the application of botanicals in tick control, with a view of providing important clues for designing new integrated tick control methods.

Chemical Constituents and Uses of Calotropis Procera and Calotropis Gigantea – A Review (Part I – The Plants as Material and Energy Resources)

The traditional and current use of Calotropis procera and C. gigantea, two soft-wooded, xerophytic shrubs of the family Apocynaceae, are reviewed against the background of the plants' chemical constituents and their biological properties. The focus is on the usage of the plants for building materials, natural pesticides, animal feed and bioremediative purposes.