Identification of anti-babesial activity for four ethnoveterinary plants in vitro

Next generation sequencing-aided screening, isolation, molecular identification, and antimicrobial potential for bacterial endophytes from the medicinal plant, Elephantorrhiza elephantina

Elephantorrhiza elephantina, a wild plant in southern Africa, is utilized in traditional medicine for various ailments, leading to its endangerment and listing on the Red List of South African Plants. To date, there have been no reports on bacterial endophytes from this plant, their classes of secondary metabolites, and potential medicinal properties. This study presents (i) taxonomic characterization of bacterial endophytes in leaf and root tissues using 16S rRNA, (ii) bacterial isolation, morphological, and phylogenetic characterization, (iii) bacterial growth, metabolite extraction, and LC-MS-based metabolite fingerprinting, and (iv) antimicrobial testing of bacterial crude extracts. Next-generation sequencing yielded 693 and 2,459 DNA read counts for the rhizomes and leaves, respectively, detecting phyla including Proteobacteria, Bacteroidota, Gemmatimonadota, Actinobacteriota, Verrucomicrobiota, Dependentiae, Firmicutes, and Armatimonodata. At the genus level, Novosphingobium, Mesorhizobium, Methylobacterium, and Ralstonia were the most dominant in both leaves and rhizomes. From root tissues, four bacterial isolates were selected, and 16S rRNA-based phylogenetic characterization identified two closely related Pseudomonas sp. (strain BNWU4 and 5), Microbacterium oxydans BNWU2, and Stenotrophomonas maltophilia BNWU1. The ethyl acetate:chloroform (1:1 v/v) organic extract from each isolate exhibited antimicrobial activity against all selected bacterial pathogens. Strain BNWU5 displayed the highest activity, with minimum inhibitory concentrations ranging from 62.5 μg/mL to 250 μg/mL against diarrhoeagenic Escherichia coli, Escherichia coli O157:H7, Salmonella enterica, antibiotic-resistant Vibrio cholerae, Staphylococcus aureus, Bacillus cereus, and Enterococcus durans. LC-MS analysis of the crude extract revealed common antimicrobial metabolites produced by all isolates, including Phenoxomethylpenicilloyl (penicilloyl V), cis-11-Eicosenamide, 3-Hydroxy-3-phenacyloxindole, and 9-Octadecenamide.

Babesiosis: Current status and future perspectives in Pakistan and chemotherapy used in livestock and pet animals

Babesiosis is a protozoal disease affect livestock and pet animals such as cattle, buffaloes, sheep, goats, horses, donkeys, mules, dogs, and cats. It causes severe economic losses in livestock as well as in pet animals. A large number of dairy animals are imported in order to fulfill the demands of milk, milk, meat and its products. In addition, different pet animals are transported from Pakistan to various parts of the world, therefore, it is important to identify the current status and distribution of babesiosis throughout Pakistan in order to control the disease and draw attention for future research, diagnosis, treatment and control of this diseases. No work has been done on a complete review on up-to-date on blood protozoal disease burden in Pakistan. This article will provide about the complete background of babesiosis in ruminants, equines and pet animals, its current status, distribution, vectors in Pakistan and allopathic and ethnoveterinary treatments used against babesiosis. Babesiosis may be subclinical (apparently normal) and may be clinical with acute to chronic disease and sometimes fatal. Babesia is found and develops inside the erythrocytes (red blood cells). Clinically, it causes fever, fatigue, lethargy, pallor mucus membranes, malaise, cachexia, respiratory distress, jaundice, icterus, hemolytic anemia, hemoglobinuria, lymphadenopathy, chollangocytitis, hepatomegaly, and splenomegaly. Chemotherapy for babesiosis includes Imidocarb dipropionate, Diaminazine aceturate Atovaquone and Bupravaquone, Azithromycin, Quinuronium sulfate and Amicarbalidesio-thionate are most widely used. Supportive therapy includes multivitamins, fluid therapy, antipyretics intravenous fluids, and blood transfusions are used if necessary. In addition, there are certain ethnoveterinary (homeopathic) ingredients which having anti-babesial activity. As the resistance against these drugs is developing every day. New more specific long-lasting drugs should be developed for the treatment of Babesiosis. Further studies should be done on disease genome of different species of Babesia for vaccine development like malarial parasites.

Twenty Years of Equine Piroplasmosis Research: Global Distribution, Molecular Diagnosis, and Phylogeny

Equine piroplasmosis (EP), caused by the hemoparasites Theileria equi, Theileria haneyi, and Babesia caballi, is an important tick-borne disease of equines that is prevalent in most parts of the world. Infection may affect animal welfare and has economic impacts related to limitations in horse transport between endemic and non-endemic regions, reduced performance of sport horses and treatment costs. Here, we analyzed the epidemiological, serological, and molecular diagnostic data published in the last 20 years, and all DNA sequences submitted to GenBank database, to describe the current global prevalence of these parasites. We demonstrate that EP is endemic in most parts of the world, and that it is spreading into more temperate climates. We emphasize the importance of using DNA sequencing and genotyping to monitor the spread of parasites, and point to the necessity of further studies to improve genotypic characterization of newly recognized parasite species and strains, and their linkage to virulence.

Elephantorrhiza elephantina: Traditional Uses, Phytochemistry, and Pharmacology of an Important Medicinal Plant Species in Southern Africa

Elephantorrhiza elephantina is used in southern Africa as traditional remedy for a wide range of human diseases and ailments including dermatological diseases, gastrointestinal system disorders, sexual dysfunction, sexually transmitted infections, and wounds. The rhizome decoction of E. elephantina is widely used by small-scale farmers in Botswana and South Africa as ethnoveterinary medicine for cattle, goats, horses, pigs, poultry, and sheep. Several classes of phytochemical compounds including anthocyanidins, anthraquinones, esters, fatty acids, phenolic compounds, flavonoids, glycosides, polysterols, saponins, sugars, tannins, and triterpenoids have been isolated from E. elephantina. Scientific studies on E. elephantina indicate that it has a wide range of biological activities including anthelmintic, antibacterial, antifungal, anti-inflammatory and antinociceptive, antiplasmodial, antioxidant, antibabesial, and antirickettsial activities. Elephantorrhiza elephantina is a valuable source of traditional medicine in southern Africa that it is worth additional research attention because of its wide ethnomedicinal applications and promising biological activities. However, the current health-related information on E. elephantina is not sufficiently explored as diverse studies on its chemical and pharmacological activities are required to understand its mechanism of action and to characterize the metabolites responsible for these activities.

Theileria equi isolates vary in susceptibility to imidocarb dipropionate but demonstrate uniform in vitro susceptibility to a bumped kinase inhibitor

Background

The apicomplexan hemoparasite Theileria equi is a causative agent of equine piroplasmosis, eradicated from the United States in 1988. However, recent outbreaks have sparked renewed interest in treatment options for infected horses. Imidocarb dipropionate is the current drug of choice, however variation in clinical response to therapy has been observed.

Methods

We quantified the in vitro susceptibility of two T. equi isolates and a lab generated variant to both imidocarb dipropionate and a bumped kinase inhibitor compound 1294. We also evaluated the capacity of in vitro imidocarb dipropionate exposure to decrease susceptibility to that drug. The efficacy of imidocarb dipropionate for clearing infection in four T. equi infected ponies was also assessed.

Results

We observed an almost four-fold difference in imidocarb dipropionate susceptibility between two distinct isolates of T. equi. Four ponies infected with the less susceptible USDA Florida strain failed to clear the parasite despite two rounds of treatment. Importantly, a further 15-fold decrease in susceptibility was produced in this strain by continuous in vitro imidocarb dipropionate exposure. Despite a demonstrated difference in imidocarb dipropionate susceptibility, there was no difference in the susceptibility of two T. equi isolates to bumped kinase inhibitor 1294.

Conclusions

The observed variation in imidocarb dipropionate susceptibility, further reduction in susceptibility caused by drug exposure in vitro, and failure to clear T. equi infection in vivo, raises concern for the emergence of drug resistance in clinical cases undergoing treatment. Bumped kinase inhibitors may be effective as alternative drugs for the treatment of resistant T. equi parasites.

Evaluation of medicinal turpentine used for the prevention of bovine babesiosis in southern KwaZulu-Natal and the eastern Free State

Medicinal turpentine has been used extensively in the eastern Free State and KwaZulu-Natal provinces of South Africa with reportedly excellent results. It is believed that it is able to prevent and treat babesiosis (redwater) in cattle. Redwater is an often-fatal disease in cattle and results in losses of large numbers every year in South Africa. This study was initiated in an attempt to investigate the validity of the use of the turpentine as a medicinal agent. Using a semi in vitro screening assay, Babesia caballi grown in primary equine erythrocytes was exposed to various concentrations of turpentine in comparison to diminazene and imidocarb. The turpentine had no parasiticidal effect following direct exposure. During the recovery phase, the previously exposed parasites appeared to grow more slowly than the controls. In comparison, diminazene and imidocarb were 100% effective in killing the parasites. In a subsequent tolerance study in adult cattle (n = 6) at 1x (2 mL), 3x and 5x the recommended dose, the product was non-toxic. Irritation was noted at the injection site with the higher dose. The only major finding on clinical pathology was a general increase in globulins, without a concurrent change in native babesia antibody titres. It was concluded that it is unlikely that medicinal turpentine is an effective treatment against babesiosis.

The potential of Elephantorrhiza elephantina as an anthelminthic in goats

Elephantorrhiza elephantina Bruch. Skeels. is used by farmers in the Eastern Cape Province to control helminths in goats. An in vitro study revealed efficacy of its fractions against adult Haemonchus contortus. This study was conducted to validate efficacy of fractions in vivo, on gastrointestinal nematodes in naturally infected goats. A total of 36 goats (18 males and 18 females) between ages of 8 and 12 months were used; these were randomly assigned to six treatments (A-F). For treatments A and B, goats received Prodose orange® (Albendazole 1.92 % m/v, closantel 3.94 % mv) at 2 ml/10 kg and distilled water at 0.5 ml/kg per os, respectively, whereas those under treatments C to E received aqueous fractions of E. elephantina at concentrations of 12. 5, 25, 50 and 75 mg/ml, dosed at 2 ml/10 kg. On days 1, 28 and 56, faecal samples were collected for faecal egg counts (FEC) and larval count, blood samples taken for packed cell volume (PCV) and body weights recorded to assess weight changes. The aqueous fraction caused highest the total faecal egg count reductions (TFECR) % of 81.7 %, 96.8 % and 98.6 % at doses of 25, 50 and 75 mg/kg, respectively, on day 56. This was comparable to the commercial drug Prodose orange®, which caused TFECR% of 94.9 % at the same time. The fraction also caused reduction of Haemonchus contortus and strongyloides larvae at all dose levels, but these were not significantly different (P > 0.05) to the negative control. There was an increase in body weights of animals at dose concentrations of 25, 50 and 75 mg/kg. Animals receiving the fraction had weight increases of between 3 and 4 kg by end of experiment (over 56 days), but those drenched with Prodose orange ® gained by less than 2 kg. The fraction also increased PCV levels at all doses on days 28 and 56 and this was comparable to the group on commercial drug. The reductions of FEC and worm larvae, as well as increase in PCVs are indicative that E. elephantina posses some antihelmintic properties against gastrointestinal parasites in goats. With a minimum dose concentration of 25 mg/ml being effective, this means that farmers can use little material. Increase in weight gain revealed in this study may indicate that the plant may have some nutritional value; further study is therefore called for to validate the plant for its nutritive value.

Anthelmintic screening of fractions of Elephantorrhiza elephantina root extract against Haemonchus contortus

In the previous work conducted, it was found that the root extract of Elephantorrhiza elephantina (Bruch.) Skeels. exhibited good anthelmintic efficacy against eggs and larvae of Haemonchus contortus. This study was therefore undertaken to screen fractions of the extracts of E. elephantina for their anthelmintic activity against adult H. contortus using a bioactivity-guided assay. The adult worm bioassay was conducted using aqueous, hexane and ethyl acetate fractions of the plant extracts at concentrations of 0.312, 0.625, 1.25, 2.5, 5 and 10 mg/ml in vitro. Albendazole and distilled water were used as positive and negative control, respectively. In vitro treatment of adult worms revealed concentration and time-dependent efficacy of the fractions of E. elephantina. The aqueous and ethyl acetate fractions showed a highly significant (P<0.05) motility inhibition at concentrations of 2.5 mg/ml and above after 6 h of exposure, while the hexane fraction showed a significant (P<0.05) motility inhibition at concentrations of 5 mg/ml and above. After 30 h of exposure, all the fractions showed insignificant (P>0.05) inhibition of motility. The fractions of E. elephantina also showed mortality indexes that were not significantly different to each other, as well as to the commercial drug (albendazole). Overall, the ethyl acetate and the aqueous fractions were found to possess the highest anthelmintic activity. We therefore recommend future studies to further investigate effective dosages of these fractions in vivo, as well as a full investigation into the compounds responsible for the biological activity.

In vivo validation of Aloe ferox (Mill). Elephantorrhiza elephantina Bruch. Skeels. and Leonotis leonurus (L) R. BR as potential anthelminthics and antiprotozoals against mixed infections of gastrointestinal nematodes in goats

Aloe ferox (Mill)., Elephantorrhiza elephantina Bruch. Skeels. and Leonotis leonurus (L) R. BR. are some of the plants used by farmers in the Eastern Cape Province to control worms in goats, but information on their efficacy is lacking. The study was conducted to determine efficacy of these plants on gastrointestinal nematodes in natural mixed infections in goats. Forty-eight male goats aged 8-12 months were divided into eight groups (Treatments A-H) of six animals each, balanced in terms of liveweight and worm egg count. Treatments A to F received plant extracts, three animals in each group receiving doses of 250 mg/kg and the other three receiving 500 mg/kg at concentration of 100 mg/ml, while those in G and H received Valbazen® (11.36% albendazole) at 10 mg/kg, and 0.5 ml/kg distilled water, respectively per os. Faecal samples were collected on days 0, 3, 6 and 9 for faecal egg counts (FEC), and body weights recorded on days 1 and 9. Results showed significant reductions (P < 0.05) in strongyle eggs by A. ferox extract at dose levels of 500 mg/kg on days 3, 6 and 9, while reductions in Eimeria spp. oocysts were observed on days 3, 6 and 9 for animals that received 500 mg/kg doses. E. elephantina caused significant reduction (P < 0.05) of Trichuris spp. eggs on days 3 and 6, respectively at 250 mg/kg dose level, whereas L. leonurus also caused significant reduction (P < 0.05) in FEC of Trichuris spp. and Eimeria spp. oocysts at 250 mg/kg dose level on day 9. Albendazole caused reductions (P < 0.05) in strongyle eggs on days 3 and 6, Trichuris spp. on days 3, 6 and 9, and on coccidia, it caused a reduction (P > 0.05) on day 1, whereas on days 6 and 9, there was an increase. On total mixed infections, highest FECR% were observed with the extract of A. ferox on days 3 (53%), 6 (54%) and 9 (58%) at 500 mg/kg,whereas albendazole had efficacy levels of 39%, 44% and 29% on days 3, 6 and 9, respectively. Body weight of goats from days 1 to 9 were not significant different from the control. The study revealed efficacy of A. ferox, E. elephantina and L. leonurus against gastrointestinal parasites at high doses (500 mg/kg), showing that the plants have the potential to be used as anthelminthics.

Toxicity evaluation of the aqueous extract of the rhizome of Elephantorrhiza elephantina (Burch.) Skeels. (Fabaceae), in rats

Elephantorrhiza elephantina root extract has been used as a traditional remedy for a wide range of ailments both in humans and livestock. As part of the safety assessment of the extract, acute, sub-acute and chronic toxicity tests were conducted by the oral route in rats. Male and female rats were divided into four groups consisting of five rats each and given doses of 200-1600 mg/kg bwt, 200-800 mg/kg bwt and 50-400mg/kg bwt in acute (1 day), sub-acute (14 days) and chronic toxicity (35 days), respectively. During the experiment, no deaths were observed in any groups and there were no remarkable changes in general appearance, as well as in food and water consumption. Significant (P<0.05) changes were however noted in body weights, haematological and serum biochemical parameters between the control and treated groups. Histopathological changes were also noted in kidneys, lungs, liver and spleen of rats receiving high doses. Based on these findings, it can be inferred that the plant has some potential toxicity at certain dose levels; therefore caution has to be taken when using E. elephantina for medicinal purposes.

In-vitro anthelminthic activity of crude aqueous extracts of Aloe ferox, Leonotis leonurus and Elephantorrhiza elephantina against Haemonchus contortus

Aloe ferox (Mill), Leonotis leonurus (L) R. BR; and Elephantorrhiza elephantina (Burch.) Skeels are plants frequently used by resource-limited farmers in the Eastern Cape Province to control gastrointestinal parasites in goats. A study was conducted to validate their anthelminthic activities in-vitro on the egg and larvae of the nematode parasite Haemonchus contortus. The crude aqueous extracts of leaves of A. ferox and L. leonurus; and roots of E. elephantina were used. Eggs and larvae of the parasite were incubated at 25 degrees C in aqueous extracts at concentrations of 0.625-20 mg/ml for 48 h and 7 days for the egg hatch and larval development assays respectively. Albendazole and water were the positive and negative controls respectively. Inhibition of egg hatching and larval development increased significantly (P < 0.05) with increasing concentrations of the extracts. E. elephantina and L. leonurus extracts had 100% egg hatch inhibition at concentration as low as 2.5 mg/ml and 1.25 mg/ml respectively, whereas A. ferox extracts had 100% inhibition at concentrations of 20 mg/ml. At the lowest concentration tested (0.625 mg/ml), E. elephantina inhibited egg hatching >96% and this was comparable to albendazole at the same concentration. E. elephantina and L. leonurus also totally inhibited larval development at concentrations of 1.25 mg/ml. The study provided evidence that A. ferox, E. elephantina and L. leonurus extracts possess anthelminthic activity, thus justifying their use in the treatment of GI helminthosis. There is however need to assess the safety of these plants in vivo and also to undertake in vivo efficacy studies.

Ethnoveterinary use of southern African plants and scientific evaluation of their medicinal properties

AIM OF THE STUDY

Livestock keepers in many developing countries with restricted access to orthodox veterinary healthcare services commonly use traditional remedies to treat their animals when disease is encountered. This review collates the documented use of plants in South Africa for healing various ailments in domestic animals, and records bioactivity testing that has been carried out on these plants.

MATERIALS AND METHODS

A literature survey was conducted on the use of plants in South African ethnoveterinary medicine (EVM), as well as on biological activity investigations relating to their ethnoveterinary use where available.

RESULTS

The ethnoveterinary application of plants, and results of screening studies of EVM plant extracts in various bioassays is presented. For diseases such as coughs, wounds, skin diseases, mild diarrhoea and reproductive disorders, EVM may be a cheap and easily accessible alternative to expensive pharmaceuticals. Studies on biological activity of EVM plants can provide indications of promising leads for extracts that can be developed into standardized medications to be used on a commercial basis. Isolation studies on active plants may yield pure active compounds that could be chemically modified to optimize medicinal value and reduce possible toxic effects.

CONCLUSION

In South Africa, a large proportion of the population relies on traditional remedies to treat themselves and their animals for common diseases. Only a small percentage of EVM plants have been analysed for biological activity or toxic effects, and hence research in this field offers fertile possibilities for future investigation.

Babesia gibsoni: detection during experimental infections and after combined atovaquone and azithromycin therapy

Babesia gibsoni is a protozoan parasite of dogs worldwide yet both an effective treatment and a reliable method for detecting subclinical cases of this emerging infection remain elusive. Experimental B. gibsoni infections were established in vivo to investigate the efficacy of combined atovaquone and azithromycin drug therapy and to determine the detection limits of a nested-PCR, IFAT and microscopy during various stages of infection. While atovaquone and azithromycin produced a reduction in parasitaemia, it did not eliminate the parasite and drug resistance appeared to develop in one dog. Polymerase chain reaction was found to be most useful in detecting infection in the pre-acute and acute stages, while IFAT was most reliable during chronic infections. Microscopy is suggested to be only effective for detecting acute stage infections. This study also describes the detection of B. gibsoni in tissue samples during chronic infections for the first time, suggesting possible sequestration of this parasite.