Ethnopharmacological survey of plants used for the treatment of schistosomiasis in Niono District, Mali

Anogeissus leiocarpus (DC.) Guill. & Perr. (Combretaceae): A review of the traditional uses, phytochemistry and pharmacology of African birch

Anogeissus leiocarpus (DC.) Guill. & Perr. belongs to the family Combretaceae and is used both by African traditional medical practitioners and livestock rearers to treat diseases such as African trypanosomiasis, animal diarrhoea, asthma, cancer, cough, diabetes, dysentery, erectile dysfunction, fever, giardiasis, helminthiases, meningitis, menstrual disorders, monkeypox, oral infections, poliomyelitis, sickle cell anaemia, snake bites, toothache, urinary schistosomiasis, and yellow fever. Some of these activities have been associated with the presence of polyphenols in the plant which include ellagic acid derivatives, flavonoids, stilbenes, tannins, and triterpenes. Several bioactive molecules have been identified from A. leiocarpus. These include the main active constituents, ellagitannins, ellagic acid derivates, flavonoids and triterpenes. Pharmacological studies have confirmed its antibacterial, antifungal, antihyperglycemic, antihypertensive, antimalarial, antioxidative, antiparasitic, antitumour and anti-ulcer effects. The stem bark has been investigated mainly for biological activities and phytochemistry, and it is the most mentioned plant part highlighted by the traditional users in ethnomedicinal surveys. In vitro and in vivo models, which revealed a wide range of pharmacological actions against parasites causing helminthiasis, leishmaniasis, malaria and trypanosomiasis, have been used to study compounds from A. leiocarpus. Because of its uses in African traditional medicine and veterinary practices, A. leiocarpus has received considerable attention from researchers. The current review provides a comprehensive overview and critical appraisal of scientific reports on A. leiocarpus, covering its traditional uses, pharmacological activities and phytochemistry.

Ethnobotanical Survey and Cercaricidal Activity Screening of Medicinal Plants Used for Schistosomiasis Treatment in Atwima-Nwabiagya District, Ashanti Region, Ghana

This study focused on documenting and evaluating the cercaricidal activity of medicinal plants used for schistosomiasis treatment in an endemic area in Ghana. Through semistructured questionnaires, personal interviews with herbalists in communities surrounding the Barekese dam in the Atwima-Nwabiagya district, where the disease is endemic, were carried out. Thirty medicinal plants distributed in 19 families were reported to be used for schistosomiasis treatment in the survey. Information on the plants, including scientific names, common names, families, and the used plant part were recorded. The families Apocynaceae and Euphorbiaceae recorded the highest number of plants (14% each), followed by Asteraceae (10%), Loranthaceae (7%), and Rubiaceae (7%). In vitro cercaricidal activity of methanol extracts of nine out of the thirty plants was performed by exposing human Schistosoma mansoni cercariae obtained from Biomphalaria pfeifferi to various concentrations of extracts over a duration of 240 minutes. All the plants tested demonstrated time- and concentration-dependent cercaricidal activity. With lethality being set at <1000 μg/mL, the cercaricidal activity in order of decreasing potency was as follows: Withania somnifera (LC₅₀ = 1.29) > Balanites aegyptiaca (LC₅₀ = 7.1) > Xylia evansii (LC₅₀ = 11.14) > Jathropha multifida (LC₅₀ = 12.9) > Justicia flava (LC₅₀ = 22.9) > Anopyxis klaineana (LC₅₀ = 182.81) > Ximenia americana (LC₅₀ = 194.98) > Loranthus lecardii (LC₅₀ = 223.87) > Bridelia tenufolia (LC₅₀ = 309.03) > Zanthoxylium zanthoxyloides (LC₅₀ = 851.94). Phytochemicals, including alkaloids, tannins, triterpenes, saponins, phytosterols, and flavonoids were identified in the plants. The result of this study gives scientific credence to the traditional use of these plants in the treatment of schistosomiasis and proves that the rich botanical knowledge of medicinal plants provides an incredible starting point for the discovery of new anti-schistosomal drugs for the local population.

Medicinal Plant Preparations Administered by Botswana Traditional Health Practitioners for Treatment of Worm Infections Show Anthelmintic Activities

Schistosomiasis and soil-transmitted helminths are some of the priority neglected tropical diseases (NTDs) targeted for elimination by the World Health Organization (WHO). They are prevalent in Botswana and although Botswana has begun mass drug administration with the hope of eliminating soil-transmitted helminths as a public health problem, the prevalence of schistosomiasis does not meet the threshold required to warrant large-scale interventions. Although Botswana has a modern healthcare system, many people in Botswana rely on traditional medicine to treat worm infections and schistosomiasis. In this study, ten plant species used by traditional health practitioners against worm infections were collected and tested against Ancylostoma ceylanicum (zoonotic hookworm), Heligmosomoides polygyrus (roundworm of rodents), Necator americanus (New World hookworm), Schistosoma mansoni (blood fluke) [adult and newly transformed schistosomula (NTS)], Strongyloides ratti (threadworm) and Trichuris muris (nematode parasite of mice) in vitro. Extracts of two plants, Laphangium luteoalbum and Commiphora pyaracanthoides, displayed promising anthelmintic activity against NTS and adult S. mansoni, respectively. L. luteoalbum displayed 85.4% activity at 1 μg/mL against NTS, while C. pyracanthoides displayed 78.5% activity against adult S. mansoni at 10 μg/mL.

Traditional Kenyan herbal medicine: exploring natural products' therapeutics against schistosomiasis

Praziquantel (PZQ) remains the only drug of choice for the treatment of schistosomiasis, caused by parasitic flatworms. The widespread use of PZQ in schistosomiasis endemic areas for about four decades raises concerns about the emergence of resistance of Schistosoma spp. to PZQ under drug selection pressure. This reinforces the urgency in finding alternative therapeutic options that could replace or complement PZQ. We explored the potential of medicinal plants commonly used by indigenes in Kenya for the treatment of various ailments including malaria, pneumonia, and diarrhoea for their antischistosomal properties. Employing the Soxhlet extraction method with different solvents, seven medicinal plants Artemisia annua, Ajuga remota, Bredilia micranta, Cordia africana, Physalis peruviana, Prunus africana and Senna didymobotrya were extracted. Qualitative phytochemical screening was performed to determine the presence of various phytochemicals in the plant extracts. Extracts were tested against Schistosoma mansoni newly transformed schistosomula (NTS) and adult worms and the schistosomicidal activity was determined by using the adenosine triphosphate quantitation assay. Phytochemical analysis of the extracts showed different classes of compounds such as alkaloids, tannins, terpenes, etc., in plant extracts active against S. mansoni worms. Seven extracts out of 22 resulted in <20% viability against NTS in 24 h at 100 μg/ml. Five of the extracts with inhibitory activity against NTS showed >69.7% and ≥72.4% reduction in viability against adult worms after exposure for 24 and 48 h, respectively. This study provides encouraging preliminary evidence that extracts of Kenyan medicinal plants deserve further study as potential alternative therapeutics that may form the basis for the development of the new treatments for schistosomiasis.

Cissus quadrangularis L: A comprehensive multidisciplinary review

ETHNOPHARMACOLOGICAL RELEVANCE

Cissus quadrangularis L. is a perennial herb of the Vitaceae family and is utilized comprehensively as a medicinal herb in most tropical regions by various names. This herb is documented to possess a wide-ranging ethnomedicinal uses in malaria, fever, epilepsy, gout, piles, skin diseases, colic, etc. AIM OF THE REVIEW: A organized summary of the botany, traditional uses, phytochemistry, pharmacology, toxicology, available marketed formulations and filed patents were presented to explore the future therapeutic potential and scientific potential of this herb.

MATERIALS AND METHODS

For a review of the literature, various databases were searched, including PubMed, EMBASE, and Scopus etc. From, total 408 records of this herb, we have screened 155 articles consist of desired information and available as full text. Present manuscript is structured from comprehensive information on this herb from screened 155 records. Plant taxonomy was confirmed to the database "The Plant List".

RESULTS

Phytochemical assessment as a whole indicated the presence of flavonoids, triterpenoids, alkaloids, saponins, iridoids, stilbenes, vitamins, steroids, and glycosides. A toxicity study revealed that its LD₅₀ value is above 3000 mg/kg in animals indicating its safety. A variety of pharmacological studies of aerial parts of this herb by different extracts have demonstrated analgesic, anti-inflammatory, anticonvulsant, antimicrobial, anticancer, anti-osteoporotic activity and other bone-related disorders to justify its name as Hadjod. Still, the herb has been utilized in clinical practice and several patents were filed in India and US for its antiosteoporotic property.

CONCLUSION

The studies on Cissus quadrangularis Linn. are extensive, but gaps still remain. The molecular mechanism, structure-activity relationship, potential synergistic and antagonistic effects of these components needs to be further elucidated. These findings suggest the need for further research on this herb for the management of several other chronic ailments.

Evaluation of mass drug administration for schistosomiasis and soil-transmitted helminths in school-aged children in Bankass, Mali

BACKGROUND

In 2004, Mali implemented mass drug administration (MDA) aimed at controlling schistosomiasis and soil-transmitted helminths. Despite several rounds of MDA, the health district of Bankass reported low coverage (64.8%) for praziquantel and albendazole in 2017, meaning that this district was still facing challenges in accomplishing the targeted 75% coverage. This study aimed to explore the barriers and gaps that hindered MDA implementation in Bankass.

METHODS

A cross-sectional study was performed. Questionnaires were administrated to all school-aged children in randomly selected villages. Technical directors of community health centers and community drug distributors in the selected villages were included in the interviews.

RESULTS

A total of 2128 children and 52 health workers were interviewed. Coverage rates were 93.51% (1990/2128) for praziquantel and 95.25% (2027/2128) for albendazole. Among the untreated children, 31.63% (31/98) reported being unaware of the campaign and 26.53% (26/98) were unable to reach the distribution points. Most of the health workers suggested increasing incentives.

CONCLUSION

The data showed satisfactory coverage >90%, in contrast with lower rates initially reported by the district health information system. These results raise concerns about the reliability of programmatic data and highlight the importance of population-based surveys for the evaluation of control interventions.

[Acute and subacute toxicity of Garcinia huillensis Baker, a plant used against urogenital schistosomiasis in Haut-Katanga, DR Congo]

This research evaluated acute and subacute toxicity of aqueous and methanolic extract from stem bark of Garcinia huillensis Baker, a plant used in Congolese traditional medicine against urogenital schistosomiasis. The acute toxicity is evaluated on guinea pigs by single oral administration of 1500, 2000, 2500, 3000 and 3500mg/kg of body weight of extracts based on the method described by protocol 423 of the Organization for Cooperation and Economic Development. Subacute toxicity is assessed after 28 days after daily administration of 4.5, 45, 450 and 1500mg/kg of body weight of extracts. Weight evolution, hematological and biochemical parameters of the guinea pigs that survived were analyzed and compared with those of the controls. Acute oral toxicity data were used to calculate the LD₅₀ of 2717.39 and 2625.00mg/kg bw for the aqueous and methanolic extract, respectively. Some signs of intoxication were noted, and certain haematological and biochemical parameters analyzed in the treated guinea pigs sometimes presented statistically significant differences compared to those of the controls. The minimum tolerated dose (1652.17mg/kg bw) found for the aqueous extract is far greater than the therapeutic dose administered by traditional therapists (4.5mg). Thus, the study shows that the stem bark of G. huillensis would be moderately toxic and would present a good margin of safety under the conditions of our experimentation, which would justify the non-toxic use of the plant under the traditional conditions of preparation and oral administration.

Ziziphus mucronata Willd. (Rhamnaceae): it's botany, toxicity, phytochemistry and pharmacological activities

Ziziphus mucronata is an important multi-purpose plant species that has been used in African traditional medicine for ages in the treatment of various devastating human and animal infections. The current paper is aimed at providing an overview of uses, toxicology, pharmacological properties and phytochemistry of Z. mucronata. The information used in the current work was retrieved using various search engines, including Pubmed, Science Direct, Google Scholar, Scielo, SciFinder and Scopus. The key words used included Ziziphus mucronata, secondary metabolites, chemistry, biological activity and pharmacology, anti-inflammatory, antimicrobial, antifungal, antiviral, ethnobotanical survey, medicinal uses, safety, toxicology and other related words. Out of the 46 infections which the plant species is used to treat, the most common uses includes sexually transmitted infections, skin infections, diarrhoea and dysentery, respiratory and chest complaints and gynaecological complaints (citations ≥6). Pharmacologically, the plant species exhibited a potential antimicrobial activity yielding a minimum inhibitory concentration of <1 mg/ml against important pathogens which includes Mycobacterium tuberculosis, Moraxella catarrhalis, Staphylococcus aureus, Escherichia coli, Propionibacterium acnes, Candida albicans, Cryptoccoos neoformans amongst other microorganisms. Furthermore, the extracts and compounds from Z mucronata revealed potent antiviral, antioxidant, anti-inflammatory and other activities in vitro. Phytochemically, cyclo-peptide alkaloids (commonly called mucronines) dominates and in conjunction with triterpenes, flavonoids, phenolic acids and anthocyanins. Besides these compounds, the plant species exhibited the presence of important in minerals. These phytoconstituents may well explain the reported biological activities. Although the extracts revealed no cytotoxic effect to Vero cells, further toxicological characteristics of the plant species still needs to be explored. There is also a need to carry out the comprehensive safety profiles of the plant species, including heavy metal detection. Although the plant species revealed important biological activities, which includes antimicrobial, antiviral, anti-diabetic, anti-inflammatory, anti-oxidant, anti-plasmodial, anthelmintic, and anti-anaemic activity in vitro, further research is needed to explore the in vivo studies, other compounds responsible for such activities and the mechanisms of action thereof. Such activities validates the use of the plant species in traditional medicine. The data on the possible use of the plant species in the treatment of diarrhoea, sexually transmitted infections, skin related and gynaecological complaints are scant and still needs to be explored and validated both in vitro and in vivo. Furthermore, the anticancer and anthelmintic activity of the plant species also needs to be explored.

Ethnobotanical study of medicinal plants in the Adrar Province, Mauritania

ETHNOPHARMACOLOGICAL RELEVANCE

Mauritania is a country in which few ethnobotanical studies have been conducted and consequently the ethnomedical data is scarce. Since the geographical region reflects the transition between tropical and Northern Africa, influenced by the Mediterranean floristic region, the traditional knowledge was influenced by several cultures from tropical Africa as well as Arab, Berber and Islamic societies.

AIM OF THE STUDY

This paper aims to explore and compile the diversity of ethnomedical knowledge in one of the regions of Mauritania and to compare the data with similar studies from surrounding territories.

MATERIALS AND METHODS

Surveys and interviews were carried out in 11 villages of Adrar province in northern Mauritania. Data were collected through open, semi-structured interviews (with individuals and focus groups). A sample of 120 people aged between 20 and 70 years, including 24 herbalists and 28 traditional healers was included.

RESULTS

Ethnomedical data for 68 plant species belonging to 27 families were obtained. They are used to treat 50 health conditions grouped in 14 pathological groups. Remedies for digestive system disorders, skin problems and respiratory ailments were among the most frequent indications. Leaves were the most frequently used plant part and remedies generally used as a powder for the various applications and a total of 2'317 use reports were gathered. About 55% of the reported species were not cited previously in the literature focusing on Mauritania and neighbouring countries. Moreover, only 6 species are also cited by Ibn al-Baytar (13th century CE).

CONCLUSIONS

This work shows a promising perspective for future studies, shedding light on the richness and the risk for conservation of traditional knowledge of herbal medicine in Mauritania.

Mapping evidence of the concomitant management of schistosomiasis by traditional health practitioners and health care professionals in communities with high prevalent infections: a systematic scoping review protocol

BACKGROUND

Schistosomiasis is one of the most prevalent parasitic diseases in low- and middle-income countries (LMICs), being regarded as a neglected tropical disease in sub-Saharan Africa. Praziquantel is the conventional treatment recommended for schistosomiasis in mainstream healthcare systems. In many poor settings, while many people reportedly use both traditional medicine and public sector mainstream healthcare systems, little is known if those infected with schistosomiasis use both African traditional and prescribed antischistosomal medicines. This review aims to map evidence of the concomitant management of schistosomiasis by traditional health practitioners (THPs) and health care professionals (HCPs) in communities with a high prevalence schistosomiasis infection in LMICs.

METHODS/DESIGN

Guided by Arksey and O'Malley scoping review framework and Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA), we will map the evidence from relevant studies dating from 2007 to 2019 published in LMICs. An electronic keyword search of the following databases will be conducted: PubMed, Cochrane Library, the Cumulative Index to Nursing and Allied Health Literature (CINAHL), and MEDLINE via EBSCOhost, Google Scholar, and WILEY online Library. Peer-reviewed articles, gray literature sources, and reference lists will be included to identify eligible studies. Following title screening, two reviewers will independently screen the abstracts and full texts. Any study that focuses on managing schistosomiasis will be included. The data will be analyzed using thematic analysis with the help of NVIVO software version 12, with the Mixed Method Appraisal Tool (MMAT) being used to assess the quality of the included studies.

DISCUSSION

This review will map the evidence in the literature of the concomitant management of schistosomiasis by THPs and HCPs in communities with a high prevalent infection in LMICs. The review findings will be important for policy makers across the healthcare continuum and be used to inform stakeholders' consensus process to explore the development of a generic set of patient-centered quality indicators that are applicable to multiple care settings. It will also identify research gaps in schistosomiasis management in LMICs and provide direction for future research. The results will be disseminated through a peer-reviewed publication and presented in relevant conferences.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42017078198.

Review on medicinal plants and natural compounds as anti-Onchocerca agents

Onchocerciasis is a filarial vector borne disease which affects several million people mostly in Africa. The therapeutic approach of its control was based on a succession of drugs which always showed limits. The last one: ivermectin is not the least. It was shown to be only microfilaricidal and induced resistance to the human parasite Onchocerca volvulus. The approach using medicinal plants used in traditional medicine is a possible alternative method to cure onchocerciasis. Onchocerca ochengi and Onchocerca gutturosa are the parasite models used to assess anthelmintic activity of potentially anthelmintic plants. Numerous studies assessed the in vitro and/or in vivo anthelmintic activity of medicinal plants. Online electronic databases were consulted to gather publications on in vitro and in vivo studies of anti-Onchocerca activity of plants from 1990 to 2017. Globally, 13 plant families were investigated for anti-Onchocerca activity in 13 studies. The most active species were Anacardium occidentale, Euphorbia hirta and Acacia nilotica each with an LC₅₀ value of 2.76, 6.25 and 1.2 μg/mL, respectively. Polycarpol, voacamine, voacangine, ellagic acid, gallic acid, gentisic acid, 3-O-acetyl aleuritolic acid and (-)-epigallocatechin 3-O-gallate were the isolated plant compounds with anti-Onchocerca activity. Most of the assessed extract/compounds showed a good safety after in vivo acute toxicity assays and/or in vitro cytotoxicity test. The exception was the ethanol extract of Trichilia emetica, which killed completely and drastically mice at a dose of 3000 mg/kg. Several plant groups of compounds were shown active against Onchocerca sp. such as tannins, alkaloids, triterpenoids and essential oils. Nevertheless, none of the active compounds was subjected to clinical trial, to assessment of its diffusibility through nodular wall or its capability to induce genetic resistance of Onchocerca sp.

In Vitro Assessment of Anthelmintic Activities of Rauwolfia vomitoria (Apocynaceae) Stem Bark and Roots against Parasitic Stages of Schistosoma mansoni and Cytotoxic Study

Schistosomiasis is a Neglected Tropical Diseases which can be prevented with mass deworming chemotherapy. The reliance on a single drug, praziquantel, is a motivation for the search of novel antischistosomal compounds. This study investigated the anthelmintic activity of the stem bark and roots of Rauwolfia vomitoria against two life stages of Schistosoma mansoni. Both plant parts were found to be active against cercariae and adult worms. Within 2 h of exposure all cercariae were killed at a concentration range of 62.5–1000 µg/mL and 250–1000 µg/mL of R. vomitoria stem bark and roots, respectively. The LC₅₀ values determined for the stem bark after 1 and 2 h of exposure were 207.4 and 61.18 µg/mL, respectively. All adult worms exposed to the concentrations range of 250–1000 µg/mL for both plant parts died within 120 h of incubation. The cytotoxic effects against HepG2 and Chang liver cell assessed using MTT assay method indicated that both plant extracts which were inhibitory to the proliferation of cell lines with IC₅₀ > 20 μg/mL appear to be safe. This report provides the first evidence of in vitro schistosomicidal potency of R. vomitoria with the stem bark being moderately, but relatively, more active and selective against schistosome parasites. This suggests the presence of promising medicinal constituent(s).

Medicinal plants from Mali: Chemistry and biology

ETHNOPHARMACOLOGICAL RELEVANCE

Mali is one of the countries in West Africa where the health system rely the most on traditional medicine. The healers are mainly using medicinal plants for their treatments. The studies performed being the basis for this review is of importance as they will contribute to sustaining the traditional knowledge. They contribute to evaluate and improve locally produced herbal remedies, and the review gives also an overview of the plant preparations that will have the most potential to be evaluated for new Improved Traditional Medicines.

AIM OF THE REVIEW

The aim of this review is to give an overview of the studies performed related to medicinal plants from Mali in the period 1995-2015. These studies include ethnopharmacology, chemistry and biological studies of the plants that were chosen based on our interviews with the healers in different regions of Mali, and contribute to sustainable knowledge on the medicinal plants. The Department of Traditional Medicine, Bamako, Mali, is responsible for registering the knowledge of the traditional healers on their use of medicinal plants and also identifying compounds in the plants responsible for the bioactivities claimed. The studies reported aimed at getting information from the healers on the use of medicinal plants, and study the biology and chemistry of selected plants for the purpose of verifying the traditional use of the plants. These studies should form the basis for necessary knowledge for the development of registered Improved Traditional Medicines in Mali.

MATERIALS AND METHODS

The healers were the ethnopharmacological informants. Questions asked initially were related to wound healing. This was because the immune system is involved when wounds are healed, and additionally the immune system is involved in the majority of the illnesses common in Mali. Based on the results of the interviews the plant material for studies was selected. Studies were performed on the plant parts the healers were using when treating their patients. Conventional chromatographic and spectroscopic methods were used for the isolation and structural elucidation of compounds. The compounds to study were selected based on the bioassays performed concomitant with the fractionation.

RESULTS

Our results show that plants traditionally used as wound healing agents contain polysaccharides basically of pectin nature with immunomodulating activities. These pectins all have different and new structures. Several of the plants also contain compounds with effects related to antioxidant properties. These compounds are mainly of polyphenolic nature. Three of these are new compounds from Nature, while 32 was for the first time described from the plant they were isolated from. This review gives an overview of the most important results obtained during the 20 year long collaboration between Department of Traditional Medicine, Bamako, Mali, and Department of Pharmacognosy, School of Pharmacy, University of Oslo, Norway.

CONCLUSION

Our studies showed that ethnopharmacological information is important for the determination of screening and chemical methods to be used for studies of plants used in traditional medicine.

Effects of Ficus thonningii extracts on the gastrointestinal tract and clinical biochemistry of suckling rats

BACKGROUND

Ficus thonningii is commonly used in traditional medicine across the African continent. We investigated the effects of crude Ficus thonningii extracts on growth, morphology and morphometry of the abdominal viscera and clinical biochemistry of neonatal rats.

MATERIALS AND METHODS

Forty, 6-day old Sprague Dawley rat pups were orally gavaged once daily with either low (50 mg.kg(-1) b.w) or high (500 mg.kg(-1) b.w) doses of aqueous or methanolic F. thonningii leaf extracts while the control received distilled water. After 7 days of treatment, the pups were euthanased and gross morphometric measurements of the abdominal visceral organs were recorded. Samples of the liver, caecum and proximal small intestine were processed for histology. Plasma biochemical parameters were analysed colorimetrically.

RESULTS

High methanolic doses of F. thonningii extracts exhibited trophic effects on the stomach while both aqueous and methanolic extracts had trophic effects on the ceacal mucosa of rats. No significant growth-promoting effects were observed in other visceral organs. Histological analysis revealed no mucosal damage or necrosis. Clinical biochemistry parameters were not abnormally altered. There was a significant decrease (p<0.05, ANOVA) in the plasma concentration of non-fasting glucose in the high methanolic group but triglycerides and cholesterol were unaltered.

CONCLUSION

The findings suggest that at low doses, F. thonningii extracts can be safely used without the risk of any disruption in the structural integrity of the neonatal rat GIT and function of the liver and kidneys.

Natural products as a source for treating neglected parasitic diseases

Infectious diseases caused by parasites are a major threat for the entire mankind, especially in the tropics. More than 1 billion people world-wide are directly exposed to tropical parasites such as the causative agents of trypanosomiasis, leishmaniasis, schistosomiasis, lymphatic filariasis and onchocerciasis, which represent a major health problem, particularly in impecunious areas. Unlike most antibiotics, there is no "general" antiparasitic drug available. Here, the selection of antiparasitic drugs varies between different organisms. Some of the currently available drugs are chemically de novo synthesized, however, the majority of drugs are derived from natural sources such as plants which have subsequently been chemically modified to warrant higher potency against these human pathogens. In this review article we will provide an overview of the current status of plant derived pharmaceuticals and their chemical modifications to target parasite-specific peculiarities in order to interfere with their proliferation in the human host.

Phytochemistry, pharmacology and ethnomedicinal uses of Ficus thonningii (Blume Moraceae): a review

The common wild fig, Ficus thonningii, is extensively used in African ethnomedicine for treating a number of disease conditions which include diarrhoea, urinary tract infections, diabetes mellitus, gonorrhoea, respiratory infections, and mental illnesses. This review aims to present a logical analysis of the nutritional, phytochemical and pharmacological properties of F. thonningii in relation to its therapeutic applications. A bibliographic analysis of the uses, phytochemical constituents and phytophamacological properties of Ficus thonningii was carried out using published papers, medicinal plant databases and various ethnobotanical and ethnopharmacological books. Ficus thonningii contains various bioactive compounds which include alkaloids, terpenoids, flavonoids, tannins and active proteins, all of which contribute to its curative properties. In vitro and in vivo pharmacological studies revealed that F. thonningii possesses antimicrobial, antidiarrhoeal, antihelmintic, antioxidant, anti-inflammatory and analgesic properties. Acute and sub-chronic toxicity studies have shown that Ficus thonningii is non-toxic if administered orally in low doses. Scientific research has validated the ethnomedicinal claims that Ficus thonningii is useful in disease management. However, there is need to continue identifying, isolating and quantifying the active principles and possibly determine the mechanisms underlying its curative properties.

In vitro anthelmintic activity of crude extracts of five medicinal plants against egg-hatching and larval development of Haemonchus contortus

ETHNOPHARMACOLOGICAL RELEVANCE

Senna occidentalis, Leonotis ocymifolia, Leucas martinicensis, Rumex abyssinicus, and Albizia schimperiana are traditionally used for treatment of various ailments including helminth infection in Ethiopia.

MATERIALS AND METHODS

In vitro egg hatch assay and larval development tests were conducted to determine the possible anthelmintic effects of crude aqueous and hydro-alcoholic extracts of the leaves of Senna occidentalis, aerial parts of Leonotis ocymifolia, Leucas martinicensis, Rumex abyssinicus, and stem bark of Albizia schimperiana on eggs and larvae of Haemonchus contortus.

RESULTS

Both aqueous and hydro-alcoholic extracts of Leucas martinicensis, Leonotis ocymifolia and aqueous extract of Senna occidentalis and Albizia schimperiana induced complete inhibition of egg hatching at concentration less than or equal to 1mg/ml. Aqueous and hydro-alcoholic extracts of all tested medicinal plants have shown statistically significant and dose dependent egg hatching inhibition. Based on ED(50), the most potent extracts were aqueous and hydro-alcoholic extracts of Leucas martinicensis (0.09 mg/ml), aqueous extracts of Rumex abyssinicus (0.11 mg/ml) and Albizia schimperiana (0.11 mg/ml). Most of the tested plant extracts have shown remarkable larval development inhibition. Aqueous extracts of Leonotis ocymifolia, Leucas martinicensis, Albizia schimperiana and Senna occidentalis induced 100, 99.85, 99.31, and 96.36% inhibition of larval development, respectively; while hydro-alcoholic extracts of Albizia schimperiana induced 99.09 inhibition at the highest concentration tested (50mg/ml). Poor inhibition was recorded for hydro-alcoholic extracts of Senna occidentalis (9%) and Leonotis ocymifolia (37%) at 50mg/ml.

CONCLUSIONS

The overall findings of the current study indicated that the evaluated medicinal plants have potential anthelmintic effect and further in vitro and in vivo evaluation is indispensable to make use of these plants.

Estimation of Cholinesterase Inhibitory and Antioxidant Effects of the Leaf Extracts of Anatolian Ficus carica var. domestica and their Total Phenol and Flavonoid Contents

Ficus carica var. domestica Tsch. & Rav. (common fig) is widely grown in Turkey and exported for its edible fruits. In this study, the n-hexane, chloroform, acetone, methanol, n-butanol, and water extracts of the leaves of F. carica var. domestica were screened for their cholinesterase inhibitory and antioxidant activities. Cholinesterase inhibition against acetyl- (AChE) and butyrylcholinesterase (BChE) was measured by the spectrophotometric method of Ellman at concentrations of 25, 50, and 100 μg/mL., while antioxidant activity was tested using three in vitro methods; 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity, metal-chelation capacity, and ferric-reducing antioxidant power (FRAP). Total phenol and flavonoid contents of the extracts were determined spectrophotometrically. Our results revealed that the n-hexane and acetone extracts exerted a notable inhibition against both AChE (62.9±0.9% and 50.8±2.1%, respectively) and BChE (76.9±2.2% and 45.6±1.3%, respectively). However, they had low activity in the antioxidant tests. The chloroform extract was found to be the richest in total flavonoid content (252.5±1.1 mg/g quercetin equivalent), while the n-butanol extract had the highest total phenol amount (85.9±3.2 mg/g extract gallic acid equivalent).

Tamarindus indica L. (Fabaceae): patterns of use in traditional African medicine

To increase the understanding of the ethnopharmacology of a single species, elaboration of dispersed primary data is required. Tamarindus indica L. (Fabaceae), or tamarind, is a common tree, especially in West Africa, with a good potential to contribute to affordable local health care based on traditional medicine (TM). For this single species review, more than 60 references with detailed information on the ethnopharmacology of Tamarindus indica in the African context were selected. It showed that most prominently, the fruits are used as laxative or febrifuge throughout the Sahel and Soudan ecological zones. Tamarind bark and leaves are often involved in the treatment of wounds, especially in central West Africa. While the bark is used to treat diarrhoea in West Africa, the leaves are used for this purpose in East Africa. Our findings suggest a difference in the way tamarind is used between East and West Africa and we assess the similarities of its uses within those regions. This review demonstrates the capability of literature research to reveal knowledge by mining and compiling information from the growing body of primary ethnopharmacologic data, much of which is published in this journal. By creating a specific profile of tamarind in the context of traditional medicine throughout Africa, the authors contribute to the collection of current ethnobotanic species accounts on Tamarindus indica that tend to be qualitative and more general.

Ethnopharmacological uses of Erythrina senegalensis: a comparison of three areas in Mali, and a link between traditional knowledge and modern biological science

This paper describes ethnopharmacological knowledge on the uses of Erythrina senegalensis DC (Fabaceae) in traditional medicine in three different areas (Dioila, Kolokani and Koutiala) in Mali. Data were collected using interviews of traditional healers selected randomly. The main reported diseases for which E. senegalensis was used by the traditional healers were amenorrhea, malaria, jaundice, infections, abortion, wound, and body pain (chest pain, back pain, abdominal pain etc). The fidelity level (which estimates the agreement of traditional healers on the same area about a reported use of the plant) was calculated to compare the results from the three areas. Certain differences were noticed, the most striking was the fact that amenorrhea was the most reported disease in Dioila and Kolokani with 21% of agreement for both areas, while this use was not reported in Koutiala at all. Similarities existed between the three areas on the use of the plant against malaria and infections, although with different degree of agreement among the healers. We also report the results of a literature survey on compounds isolated from the plant and their biological activities. A comparison of these results with the ethnopharmacological information from Mali and other countries showed that some of the traditional indications in Mali are scientifically supported by the literature. For instance, the use of E. senegalensis against infectious diseases (bilharzias, schistosomiasis, pneumonia etc.) is sustained by several antibacterial and antifungal compounds isolated from different parts of the plant. The comparison also showed that pharmacologists have not fully investigated all the possible bioactivities that healers ascribe to this plant.