Tyrosinase modulation by five Rwandese herbal medicines traditionally used for skin treatment

Ethnopharmacological relevance

Traditional herbal medicines provide an interesting, largely unexplored source for the development of potential new drugs and skin-care cosmetics. Some herbal extracts are known to be inhibitors of melanin formation, sometimes more potent than the classical inhibitors, hydroquinone/arbutin or kojic acid, and are not associated with melanocytes cytotoxicity or mutagenicity. Such plants are used in traditional medicine in many countries, particularly in Africa, for skin lightening.

Aim of the study

To evaluate in vitro the ability of Rwandese medicinal plants, traditionally used for the treatment of skin (discoloration and attenuation of discolored spots), to modulate pigmentation and tyrosinase activity.

Materials and methods

Based on an ethnopharmacological survey, five herbs [Brillantaisia cicatricosa Lindau (Acanthaceae), Chenopodium ugandae (Aellen) Aellen (Chenopodiaceae), Dolichopentas longiflora Oliv. (Rubiaceae), Protea madiensis Oliv. (Proteaceae) and Sesamum angolense Welw. (Pedaliaceae)] were selected. Twenty-seven extracts, obtained by treating the herbs with increasing polarities solvents, were investigated for their effects on cell viability (MTT test) and on pigmentation: inhibition of the enzyme tyrosinase (colorimetry of reaction products, measurement of enzyme activity, TLC-autography; studies on crude cellular extracts obtained from normal melanocytes and on a mushroom tyrosinase) and measurement of melanogenesis by human melanoma cells.

Results

None of the tested plant extracts were cytotoxic on tested human melanoma cell lines, except for Dolichopentas longiflora (IC₅₀ of leaves n-hexane extract, 4 μg/ml for MM028 and 4.5 μg/ml for MM001; IC₅₀ of roots ethyl acetate extract, 0.8 μg/ml for MM028 and 3.9 μg/ml for MM001). Almost all extracts inhibited melanogenesis in a melanoma whole cells overall pigmentation assay, a model reflecting the entire cycle of melanogenesis. All the Protea madiensis extracts quite strongly inhibited melanogenesis and, surprisingly, one of the Dolichopentas longiflora leaves extracts was found to increase melanogenesis. These results were confirmed by the modulation of pigmentation reactions by crude cellular extracts obtained from normal melanocytes; interestingly, one of the extracts (Dolichopentas longiflora ethyl acetate extract) is even more active (61% at 500 μg/ml) than kojic acid (<3% at 142 μg/ml and 68% at 1421 μg/ml). In a mushroom tyrosinase inhibition assay, data obtained on some extracts fairly agree with pigmentation inhibition measured on melanocytes proteins as, for example, the methanol extract of Protea madiensis. While a few others extract display discording data, this probably reflects either differences between human and mushroom tyrosinase, interference with melanocytes enzymes at later steps than tyrosinase or the simultaneous presence of compounds with conflicting activities in a given extract.

Conclusions

Ethnopharmacological data represent an efficient approach to discover active herbs. Some of the selected medicinal plants clearly show potent tyrosinase inhibitions while one extract significantly increases cell pigmentation; one extract contains potent growth melanocytes inhibitors.     

Ethnobotanical survey on medicinal plants used by Guinean traditional healers in the treatment of malaria

Ethnopharmacological relevance

The objective of the present study was to collect and document information on herbal remedies traditionally used for the treatment of malaria in Guinea.

Materials and methods

The survey was carried out from May 2008 to September 2010 and targeted traditional medical practitioners and herbalists. The questionnaire and oral interviews were based on the standardized model which was prepared by the “Centre de Recherche et de Valorisation des Plantes Médicinales (CRVPM) – Dubréka”.

Results and discussion

A total of 258 people (141 males and 117 females) from which 150 traditional healers and 108 herbalists were interviewed. The age of informants ranged from 28 to 82 years old. 57% (149/258) of the interviewees were more than 50 years old. The respondents had good knowledge of the symptoms of malaria, and a fairly good understanding of the causes. One hundred thirteen plant species were recorded, out of which 109 were identified. They belonged to 84 genera and 46 families. The most frequently cited plants were Vismia guineensis, Parkia biglobosa, Nauclea latifolia, Harungana madagascariensis, Terminalia macroptera, Crossopteryx febrifuga, Terminalia albida, Annona senegalensis, and Nauclea pobeguinii. The leaves were most frequently used (80/113 species), followed by stem bark (38/113 species) and roots (4/113 species). The remedies were mostly prepared by decoction (111 species), followed by maceration (seven species). Only one species was prepared by infusion.

Conclusion

The present study showed that traditional healers in Guinea have a consistent knowledge of antimalarial plants. Further research should be carried out to compare the anti-malarial activity of the different species, and to check if their use against malaria can be scienti?cally validated.     

Traditional uses of herbal vapour therapy in Manipur,North East India: An ethnobotanical survey

Ethnopharmacological relevance

Vapour-based medicines are an aspect of traditional medicine in North East India. However, no collective studies on this therapy in the region have been attempted. With the changing perception of traditional knowledge, documenting these herbal preparations and the subsequent development of baseline data for applications in further ethnopharmacological research are needed.

Aims of the study

To survey and document the plant species associated with vapour therapy in Manipur, North East India, and to evaluate these traditional practices.

Materials and methods

Semi-structured questionnaires were used to collect information from the Meitei community in the Imphal valley and the Jiribam area in Manipur. Traditional disease concepts were studied along with their corresponding medical terminologies. Plant samples collected from fields, healers' private collections and home gardens were identified. Evaluation of the ethnobotanical data was performed with a modified fidelity level index.

Results

In the study, 41 traditional disease complexes were treated by 13 different routes of administration using 48 mono-ingredient and 17 multi-ingredient compositions. Preparation methods included boiling in water (28%), burning the materials (48%), crushing the materials to release the aroma (21%) and slight heating of the materials (3%). Some of the mono-ingredient recipes reported in the study were observed to have similar uses in other parts of the world, whereas polyherbal remedies were found to be unique without any similar report.

Conclusion

Many compositions mentioned in the paper are still used by the Meitei community. Traditional healers follow their own criteria for selecting medicinal plants. Plants recorded in this ethnobotanical study can suggest methods for selecting and identifying potentially effective plants for future drug candidates. Scientific characterisation of the herbal remedies can contribute to the endorsement of traditional vapour-based therapies in the modern health care systems. Findings from these “new usage” reports of plants and unique combinations of polyherbal compositions indicate the importance of such documentation efforts.     

Danggui to Angelica sinensis root: Are potential benefits to European women lost in translation? A review

Ethnopharmacological relevance

Danggui (Chinese Angelica root; Dong quai; Angelica sinensis (Oliv.) Diels.) is a traditional Chinese herbal remedy with a long history of use in China, Korea and Japan. Even today it is still one of the herbs most commonly used by Traditional Chinese Medicine (TCM) practitioners in China, as well as Europe. It is mainly used for the treatment of women's reproductive problems, such as dysmenorrhea, amenorrhoea, menopause, among others. Using Angelica sinensis (Oliv.) Diels. root as the example, this Review examines the ease with which the use of a Traditional Chinese Herbal Remedy can be transposed from one culture to another. By examining the more recent literature, a number of aspects are considered by the author to be potentially lost in translation: (i) identity and quality (phytochemistry); (ii) tradition of use and processing (smoke-drying, stir-frying, with and without wine); (iii) method of use and traditional types of Chinese herbal medicines; (iv) ethnic differences (Caucasian vs. Asian); (v) efficacy, safety and potential for western drug–herb interactions.

Materials and methods

This review is based on evaluation of the literature available in scientific journals, textbooks, electronic sources such as ScienceDirect, PubMed, Scopus, etc., as well as other web-sites.

Results

A vast amount of information concerning the use of Angelica sinensis exists in the public domain. Many aspects associated with the use of the root are deemed problematical, such as identity, processing, amount and types of constituents, tradition of use in combination with other Chinese herbs, ethnicity of users, etc. Numerous constituents have been isolated with phthalides, ferulic acid and polysaccharides showing biological activities.

Conclusion

In spite of the potential activities associated with the traditional use of danggui, and the many trials using the Chinese system of ‘Zheng differentiation’, well-designed western-style clinical trials carried out using the authenticated, chemically standardized crude drug material to confirm clinical efficacy are in short supply. However increasing research into Angelica sinensis extracts and constituents shows that many of the traditional uses are not without scientific basis.     

Comparison of the anti-inflammatory and anti-nociceptive effects of three medicinal plants known as “Snow Lotus” herb in traditional Uighur and Tibetan medicines

Ethnopharmacological relevance

Saussurea involucrata (Kar. et Kir.) Sch.-Bip. (Compositae) has long been used under the herbal name “Snow Lotus” for the treatment of rheumatoid arthritis, stomachache and dysmenorrhea in Uighur folk medicine. In traditional Tibetan medicine, Saussurea laniceps Hand.-Mazz. and Saussurea medusa Maxim. have also been used under the name “Snow Lotus” and prescribed for the treatment of pain and inflammatory conditions.

Aim of the study

The present study evaluated the pharmacological effects of three species of “Snow Lotus” in experimental inflammation and pain models, and determined the chemical compounds that may correlate with their pharmacological activities.

Materials and methods

The anti-inflammatory activities of the three herbs were observed by using carrageenan-induced paw edema in rats and xylene-induced ear edema in mice. Investigations on the analgesic effects were conducted, including acetic acid-induced writhing and hot-plate test. An UPLC–MS method was developed to analyze the chemical composition of the three herbs and of plasma samples after herb administration.

Results

In rat paw edema model, the peak inhibitory effects of Saussurea laniceps and Saussurea involucrata (55.1% and 42.2%, respectively) were recorded with the dose of 400 mg/kg at 3 h post-carrageenan injection. In mouse ear edema model, oral administration of Saussurea laniceps, Saussurea involucrata and Saussurea medusa extract (400 mg/kg) resulted in a significant inhibition of ear edema by 40.9%, 33.3%, and 9.1%, respectively. In the writhing test, oral administration of Saussurea laniceps extract (100, 200 and 400 mg/kg) resulted in a significant inhibition of writhings by 13.5%, 22.3%, and 43.5%, respectively. In the hot-plate test, Saussurea laniceps extract significantly increased the latency of jumping response by 38.2% and 52.7% when treated orally at 200 and 400 mg/kg in mice, respectively. Flavonoids, coumarins and lignins were found to be present in plasma after administration of the extracts and may be the basis of the observed pharmacological effects.

Conclusion

The results clearly demonstrated that Saussurea laniceps was most effective; Saussurea involucrata exhibited a moderate potency, whereas Saussurea medusa possessed little effect against the experimental edema and pains. This study also supported discrimination among the three herbs when using them in folk medicine.     

Old plants newly discovered: Cassia sieberiana D.C. and Cassia abbreviata Oliv. Oliv. root extracts inhibit in vitro HIV-1c replication in peripheral blood mononuclear cells (PBMCs) by different modes of action

Ethnopharmacological relevance

Despite advances in anti-retroviral therapy which has transformed HIV/AIDS from a fatal to a manageable chronic disease, increasing viral drug resistance, side effects and uneven access to anti-retroviral drugs remain considerable therapeutic challenges. Partly as a consequence of these shortcomings and partly based on the fact that HIV/AIDS gives rise to opportunistic infections whose symptoms have been managed in Africa in an HIV/AIDS-independent context by traditional healers for centuries, many HIV/AIDS patients use herbal medicines. The aim of this study was to screen selected medicinal plants from Botswana, used by traditional healers to treat/manage HIV/AIDS, for inhibitory activities on HIV replication.

Materials and methods

Based on an ethnomedical survey, ethanolic tannin-containing and tannin-free extracts from 10 medicinal plants were tested for inhibitory properties against a clone of HIV-1c (MJ₄) measuring cytopathic effect protection and levels of viral p24 antigen in infected PBMCs.

Results

Cassia sieberiana D.C., Cassia abbreviata Oliv. Oliv. and Plumbago zeylanica L. extracts showed significant inhibition of HIV-1c (MJ₄) replication. The inhibitory activity of the Plumbago zeylanica extract could be attributed to its tannin content. Anti-HIV activity of Cassia sieberiana root and bark extracts, and Cassia abbreviata root extracts occurred in a concentration-dependent manner with an effective concentration (EC₅₀) of 65.1 μg/ml, 85.3 μg/ml and 102.8 μg/ml, respectively. Experiments to elucidate possible mechanism(s) of action revealed that Cassia sieberiana root and bark extracts blocked HIV replication at its binding- (EC₅₀ = 70.2 μg/ml and 90.8 μg/ml, respectively) and entry stage (EC₅₀ = 88.9 μg/ml and 100.5 μg/ml, respectively) while Cassia abbreviata extracts did not.

Conclusions

We report here for the first time a direct inhibitory effect on HIV-1c replication of extracts from two extremely popular medicinal plants, Cassia sieberiana and Cassia abbreviata. Considering the traditional uses of both Cassia species, our findings strongly suggest pilot clinical observational studies involving traditional healers to further evaluate the therapeutic potential of the Cassia extracts.     

Traditional plant-based remedies to control gastrointestinal disorders in livestock in the regions of Kamina and Kaniama (Katanga province,Democratic Republic of Congo)

Ethnopharmacological relevance

Gastrointestinal parasitic diseases present one of the main constraints hindering the productivity of the livestock sector (goat and cattle). Due to the limited availability and affordability of deworming drugs, traditional herbal remedies are still frequently used. The study aims at collecting traditional knowledge on local plants and remedies used to treat gastrointestinal parasitoses in livestock in two adjacent territories (Haut-Lomami district).

Material and methods

A field survey was carried out in a part of the Haut-Lomami district (province of Katanga). A semi-structured questionnaire was used to interview 44 people including farmers, traditional healers and livestock specialists (veterinarians and agronomist), identified as using or practicing traditional medicine. To prepare botanically identified herbarium specimens, cited plants were collected with the participation of interviewed people.

Results

Although interviewed people cannot precisely identify the etiology of gastrointestinal disorders/parasitoses in domestic animals, they treat the condition with herbals collected in their near environment. Nineteen different traditional remedies were collected and described; 9 plant species were identified as commonly used to treat gastrointestinal parasitic infections. From these, Vitex thomasii De Wild (Verbenaceae) appears as the plant most often used.

Conclusion

This survey contributed to the establishment of an inventory of plants used in livestock parasitic treatment in this region of the Democratic Republic of Congo. Future studies are needed to confirm the efficacy and safety of these traditional remedies.     

Traditional uses of plants in the Eastern Riviera (Liguria,Italy)

Aim of the study

The aim of the present study was to explore the traditional plant knowledge of a zone of the Ligurian coast, known as Riviera spezzina (RS), Eastern Liguria, Italy.

Materials and methods

Ethnobotanical information was obtained through open informal interviews. The informants were residents, belonging to families living in the study area since generations, and involved, at least partially, in agriculture.

Results and conclusions

A total of 120 botanical taxa were recorded. Ethnobotanical data included medicinal (40.4%), alimentary (46.5%), veterinary (4.6%), domestic and cosmetic (4.3%), magic and ritual (1.8%) and other uses (2.4%). Medicinal plants are used to treat a wide range of diseases, mainly disorders of digestive system, skin, and genital–urinary and respiratory traits. The key role played by undomesticated edible herbs, locally known as “erbette”, in traditional cooking recipes of RS was shown. These botanicals are rich in bioactive compounds, such as polyphenols, vitamins, complex sugars, essential fatty acids and fibers, and therefore might offer a valid protection against pathological conditions. Plant uses by RS people were compared with previous ethnobotanical literature, concerning the neighbouring areas of Liguria. Our results highlight the role of the traditional use of plants in the maintenance of health and the prevention of chronic and age-related diseases.     

Investigation into the mechanism of Eucommia ulmoides Oliv. based on a systems pharmacology approach

Ethnopharmacology relevance

Though Traditional Chinese Medicine (TCM) has long been playing a significant role in the maintenance of health for people in Asia as well as many other places, the mechanism of its action still remains ambiguous for most of the plants used in TCM, such as Eucommia ulmoides Oliv., a kind of herb that is widely used to help regulate hypertension and the immune system nowadays. However, its functioning mechanism is still unknown. Thus it is necessary to exploit the mechanism of Eucommia ulmoides Oliv.

Methods

A systems pharmacology approach combining drug-likeness evaluation, oral bioavailability prediction, multiple drug targets prediction as well as network pharmacology techniques has been used.

Results

This comprehensive systematic approach helps successfully to identify 41 candidate compounds contained in Eucommia ulmoides Oliv. while 39 potential targets hit by these ingredients and helps to uncover the synergistic mechanism of action on a systematic level.

Conclusions

Our work successfully explains the mechanism of the efficiency of Eucommia ulmoides Oliv. for the treatment of hypertension and enhancing immune. These results not only provide a new insight for the understanding of the chemical and pharmacological basis of Eucommia ulmoides Oliv., but also provide an efficient way for drug discovery from herbal medicine.     

Semen Astragali Complanati: An ethnopharmacological,phytochemical and pharmacological review

Ethnopharmacological relevance

Semen Astragali Complanati (SAC), the dried ripe seed of Flatstem Milkvetch (Astragalus complanatus Bunge) (Leguminosae), is commonly used in traditional Chinese medicine (TCM) for treating muscle, liver, kidney, blood, skin and reproductive system diseases.

Materials and methods

Relevant information about SAC was gathered via “Google Scholar”, “ISI Web of Knowledge”, “PubMed”, “ScienceDirect”, “Medline Plus”, “ACS”, “CNKI” and “Wiley Online Library” and from books in local libraries.

Results

The major contents of SAC include fatty acids, amino acids, polysaccharides, flavonoids, triterpene glycosides and trace elements. Previous scientific studies have reported that SAC exhibits a number of therapeutic effects on chronic diseases such as cardiovascular diseases, diabetes mellitus and cancers. It has been found that flavonoids are the main bioactive component in SAC. However most of the previous studies have shown the effects brought by the total flavonoid fraction extracted from SAC only; further studies are warranted for the biological effects produced by individual components. There are only a few studies on the toxicity of SAC and the overall results show that its toxicity is quite low or even non-existent.

Conclusions

SAC is a valuable TCM herb with multiple pharmacological effects for treating some chronic diseases. More studies on SAC will help us to have a better understanding of its pharmacological mechanisms so as to provide more scientific evidence to explain its traditional uses, identify its therapeutic potential on other diseases and understand its possible harmful effects. Based on previous studies, it is easy to identify that antioxidant effect of SAC might play an important role on its pharmacological effects. Studying the effects of SAC on handling intracellular reactive oxygen species may be a potential direction to help understanding the molecular mechanisms of SAC on preventing and/or treating chronic diseases.     

Hot and cold: Medicinal plant uses in Quechua speaking communities in the high Andes (Callejón de Huaylas,Ancash, Perú)

Ethno-pharmacological relevance

An ethnopharmacological survey has been set up in high altitude Quechua speaking communities dwelling in Callejón de Huaylas (Ancash department, Peru) and in medicinal plant markets in order to document the medicinal plants use of 178 species within the frame of a traditional Andean medicinal system.

Materials and methods

A sound ethnopharmacological survey was performed during the years 2011, 2012 and 2013 in different places along Callejón de Huaylas valley in the peruvian Andes, were Quechua speaking communities dwell. Two different methodologies were used: first, plant uses were recorded during walks with informants and in medicinal plant markets held on a regular bases in the area (Huaraz, Carhuaz, Yungay). Secondly, traditional healers (curanderas, curanderos) were interviewed about their practices and healing sessions were observed, in order to understand better the traditional medicinal system as a whole (disease aetiology, diagnosis, treatments, healers).

Results

Altogether, 178 medicinal species were collected. Most of the plants found on the market were also found in the wild and vice-versa. Medicinal plant trade is exclusively held by women, selling their merchandise to local people or to big retailer. Plants are classified according their hot or cold virtues, this in accordance with the local conception of the body physiology and disease aetiology, based on a hot–cold polarity. Main use notified for medicinal plants is “(bath) against cold”, a prophylactic measure against diseases of cold nature. Other uses include culture bound illnesses i.e. susto, aire, nervios, or heart pain, commonly cited in South America. Regarding symptoms, rheumatic/arthritic pain, musculoskeletal traumas, cough, pulmonary and respiratory problems, gastritis and stomach ache, were the most frequently cited. Diagnosis and treatment are intrinsically linked together and mainly based upon divination techniques using egg and cuy (Cavia porcellus L., Caviidae).

Discussion and conclusion

Medicinal plants use and traditional medicinal practices are still very vivid in Callejón de Huaylas as highlighted by the abundance of medicinal plants traded in the markets. In this business, women have a key position as healers at the family and community level. Medicinal uses of the majority of the species presented here are reported for the first time. Because medicinal plants sold on the market are collected from the wild and also because high altitude medicinal plants are generally small herbaceous species pulled out with their roots, there is a serious risk of over exploitation and extinction of endemic species.     

New finding of an anti-TB compound in the genus Marsypopetalum (Annonaceae) from a traditional herbal remedy of Laos

Ethnopharmacological relevance

There is widespread use of traditional herbal remedies in the Lao PDR (Laos). It is common practice to treat many diseases with local plants. This research project documented and analysed some of these traditional remedies used to treat symptoms of tuberculosis (TB).

Materials and methods

This research was executed by interviewing healers about plants used traditionally to treat the symptoms of TB. Samples of some of the plants were collected, and extracts of 77 species were submitted to various in vitro assays in order to determine the amount of growth inhibition of virulent Mycobacterium tuberculosis H37Rv (Mtb), as opposed to other microbes and mammalian Vero cells.

Results

Interviews took place with 58 contemporary healers in 5 different provinces about plants currently used, giving a list of 341 plants. Bioassay-guided fractionation was performed on Marsypopetalum modestum (Pierre) B. Xue and R.M.K. Saunders (Annonaceae), leading to the isolation of dipyrithione, an anti-mycobacterial compound isolated for the first time from the genus Marsypopetalum through this research.

Conclusions

This research has helped to increase awareness of Laos’ rich diversity of medicinal plants and will hopefully provide incentive to preserve the undeveloped forested areas that remain, which still hold a wealth of medical information for future discoveries.     

Traditional phytotherapy remedies used in Southern Rwanda for the treatment of liver diseases

Ethnopharmacological relevance

Liver diseases represent a major health problem due to their complications and limited treatment possibilities. In Rwanda, given low accessibility to modern treatments, most people still rely on traditional medicinal plants. The symptomatology of many hepatic troubles (icterus) is evident for traditional healers who have a high probability of selecting efficient herbal medicines.

Objectives

To document medicines used in the treatment of “hepatitis” in Southern Rwanda with the knowledge, attitudes and practices related to liver disorder recognition, control and treatment.

Materials and methods

56 traditional health practitioners, each a legal representative of an official association, were interviewed and participated in plant collection for the preparation of botanically identified herbarium specimens.

Results

68 multi-component and 65 single-component herbal recipes were identified for the treatment of liver diseases with a total of 86 different herbs from 34 families identified. The most represented were the Asteraceae and the Lamiaceae. Crassocephalum vitellinum, Hypoestes triflora and Erythrina abyssinica were the most widely used plants. The principle of polymedication for complex (i.e. multifactorial) diseases (“Ifumbi” in Rwanda), is a constant in every traditional practice. It is striking that the Rwandese therapy of liver diseases proposes so many single-herb preparations (49% of all herbal preparations). Some of the recorded plants or other species from the same genus have previously been documented for liver protection using various in vivo and in vitro models.

Conclusion

Herbal remedies for hepatitis are widely used and highly diverse in Southern Rwanda; further chemical, pharmacological and toxicological studies are clearly required to rationally develop the most important remedies.     

Management of diabetes in Guinean traditional medicine: An ethnobotanical investigation in the coastal lowlands

Ethnopharmacological relevance

This survey was carried out in the coastal lowlands of Guinea–Conakry in order to make an inventory of plants used by traditional healers, herbalists and diabetic patients for the management of diabetes mellitus.

Materials and methods

Frequent ethnomedical and ethnobotanical investigations were conducted from June 2008 to December 2009 in Conakry, Kindia, Forécariah, Dubréka, Boke, Fria and Boffa. It is a cross-sectional survey and data collection is based on the interactive method. During this period a total of 112 people aged from 39 to 76 years old were interviewed.

Results

During this investigation 146 plant species belonging to 55 families were collected. The most cited plants were Anacardium occidentale L. and Ficus spp., while the Fabaceae family was the most represented, followed by the Euphorbiaceae and Rubiaceae. The most frequently plant parts used by the traditional healers and the herbalists were the stem-bark and decoctions the most common preparation mode.

Conclusions

It is clear that a variety of plants is used in the management and treatment of diabetes. Due to the increasing prevalence of type 2 diabetes, there is an urgent need for scientific investigations to rationalise the use of these traditional remedies, which could represent accessible alternative medicines for the Guinean populations.     

Medicinal utilization of exotic plants by Bapedi traditional healers to treat human ailments in Limpopo province,South Africa

Ethnopharmacological relevance

Most exotic plants are usually labelled as alien invasives and targeted for eradication. However, some of these exotic plants play an important role in the traditional primary healthcare sector of the Bapedi culture in the Limpopo Province of South Africa. The medicinal uses of most of these species have neither been documented nor their biological activity evaluated.

Aim of the study

To make an inventory of exotic species employed by Bapedi traditional healers to treat different human ailments in the Limpopo Province, South Africa.

Materials and methods

Semi-structured interviews, observation and guided field walks with 52 traditional healers were employed to obtain ethnobotanical data during first half of 2011 on the use of exotic plant species by Bapedi healers to treat human ailments. Based on ethnobotanical information provided by these healers, specimens were collected, numbered, pressed, and dried for identification.

Results

A total of 35 exotics species belonging to 21 families and 34 genera, mostly from the Fabaceae and Solanaceae (11.4% for each), Apocynaceae and Asteraceae (8.5% for each) were used by Bapedi healers to treat 20 human ailments. Trees (45.7%) and herbs (37.1%) are the primary source of medicinal plants. Species most frequently reported were used for the treatment of hypertension (35%), diabetes mellitus, erectile dysfunction and gonorrhoea (25% for each). The highest consensus from individual accounts of the traditional healers on the use of exotic plant remedies in this study was noted for the three ailments. These were for Catharanthus roseus (gonorrhoea, 60%), Punica granatum (diarrhoea, 38.4%) and Ricinus communis (sores, 21.5%). Of the 35 exotic plant species recorded, 34.2% are regulated by the Conservation of Agricultural Resources Act (1983) (CARA) No. 43 of 1983 either as worst weeds or invaders.

Conclusion

The present study demonstrated that exotic plant species play an important part as medicinal remedies employed by Bapedi healers to treat different human diseases in the Limpopo Province. The use of these species as alternative sources of medicinal remedies could alleviate harvesting pressure of wild indigenous plants, thereby enhance biodiversity's region. However, there is a need to formulate an appropriate policy to retain some of the useful medicinal exotics (listed under CARA No. 43 of 1983) within the environment before their medicinal value vanishes as they are eradicated through management strategies adopted by the South African government.     

Ethnobotanical survey of medicinal plants used by Bapedi healers to treat diabetes mellitus in the Limpopo Province, South Africa

Ethnopharmacological relevance

Bapedi phytomedicine employ a range of plant species to treat diabetes mellitus (DM). Existing literature partially support the use of certain species for this purpose.

Aim of the study

To report on Bapedi medicinal plants employed to treat DM.

Materials and methods

A semi-structured questionnaire was employed to conduct a survey on medicinal plants used by Bapedi traditional healers in their DM management protocol. Fifty-two traditional healers from 16 municipalities, covering three districts, were interviewed during the first half of 2011.

Results

A total of 24 plant species belonging to 20 families, mostly from the Asteraceae (13%), Cucurbitaceae and Sapotaceae (8%), were used to treat diabetes mellitus. Plant parts mostly preferred were roots and leaves. A decoction of these is most commonly used to make extracts, which are then taken orally for a period of one week. Mimusops zeyheri (29%), Helichrysum caespititium (25%), Plumeria obtusa (21%), Aloe marlothii subsp. marlothii, Hypoxis iridifolia and Moringa oleifera (17% each), were repeatedly mentioned by the traditional healers as most used for the management of diabetes mellitus in the study area. Plumeria obtusa and Momordica balsamina are exclusively used to treat diabetes mellitus, and only in the Sekhukhune District.

Conclusion

It is concluded that Bapedi traditional healers do have a basic understanding of the causes and remedial action required in the treatment of diabetes mellitus.     

Medicinal plants used by the Bapedi traditional healers to treat diarrhoea in the Limpopo Province,South Africa

Ethnopharmacological relevance

This paper provides ethnobotanical information on medicinal plants used to treat diarrhoea in the Limpopo Province, South Africa. Documentation of this nature usually provides the basis for selecting medicinal plants for future phytochemical and pharmaceutical studies aimed at developing new, effective and affordable plant-derived diarrhoea remedies.

Aim of the study

To record and document medicinal plants used by the Bapedi traditional healers to treat diarrhoea in the Limpopo Province, South Africa.

Materials and methods

In order to record and document medicinal plants used by the Bapedi traditional healers to treat diarrhoea, 51 healers from 17 municipalities covering Capricorn, Sekhukhune and Waterberg districts in the Limpopo Province, South Africa were interviewed between January and July 2011. Data collected included the names of plants, plant part(s) used, methods of herbal preparation, administration, dosage and duration of treatments. Voucher specimens of the plants used by the Bapedi traditional healers to treat diarrhoea were collected, identified and deposited as future reference material at the Larry-Leach Herbarium (UNIN), University of Limpopo.

Results

A total of 20 plant species representing 16 families and 20 genera were found to be commonly used by the Bapedi traditional healers to treat and manage diarrhoea in the Limpopo Province, South Africa. The largest proportion of the medicinal plants belonged to the families Anacardiaceae, Asteraceae, Fabaceae and Malvaceae (10% each). The most frequently used species were Punica granatum (39.2%), Grewia bicolor (33.3%), Dombeya rotundifolia (21.6%), Commiphora marlothii (19.6%) and Acacia senegal (13.7%). The roots were the most commonly used plant part (50%), followed by leaves (20%), bark (15%), fruits (10%), pericarp, seed, tuber and whole plants (5% each). Mono therapies based on preparations made from a single plant species were the most dominant (90%). All medicinal preparations were taken orally for 1 week or until diarrhoea subsided. The therapeutic claims of the medicinal plants documented in this study are well supported by literature, with 70% of the species having anti-diarrhoeal properties or are used as diarrhoea remedies both in South Africa and also in other countries.

Conclusion

This study reveals that local communities in the Limpopo Province, South Africa still depend on traditional medicines for basic healthcare; and the use of traditional medicines is still an integral part of their socio-cultural life.     

Ethnobotanical survey of biopesticides and other medicinal plants traditionally used in Meru central district of Kenya

Ethnopharmacological relevance

The purpose of this study was to carry out a survey and document plants used in Meru-central district by traditional healers with emphasis on those used as biopesticides.

Materials and methods

The study was carried out at Igane and Gatuune sub-locations, Abothuguchi East division of Meru-Central district, Kenya. The data collection involving 23 traditional healers was done using semi-structured questionnaire, focused group discussion and transect walks. Plants samples were collected and botanically identified at the herbarium of the Department of Land Resource Management and Agriculture Technology in the University of Nairobi.

Results

The results of the ethnobotanical survey revealed that herbalists belonged to both gender with the majority being male (82.6%) and female (17.4%). Their ages ranged from 28 to 82 years. Seventy (70) plant species, belonging to 35 families, were identified as being used as biopesticides and also as medicinal. The families encountered were Asteraceae (10%), Euphorbiaceae (8.6%), Lamiaceae (8.6%), Fabaceae(8.6%), Caesalpiniaceae (5.7%), Rubiaceae (5.7%), Liliaceae (4.3%), Apocynaceae (2.9%), Flacourtiaceae (2.9%), Verbenaceae (2.9%) and the rest of the 24 families had 1.4% each. These medicinal plants were used to treat and manage a wide range of diseases and conditions including parasitic, microbial, helminthosis, protozoa, cuts and wounds, fractures, dental, arthritis, allergic, snake bites, reproductive as well as metabolic. Among the plants used, shrubs were the commonest at 42.8%; trees were 32.9%, while herbs and liana were at 22.9% and 1.4%, respectively. Majority of the respondents used leaves, roots and bark to make their herbal preparations with only a few using seeds, flowers, whole plant, flower sap and pods. The plants that were cited by the respondents to be used as biopesticides were Prectranthus barbatus Andr. (47.8%), Tephrosia vogelii Hookf. (39.1%), Ocimum gratissimum L (34.7%), Vernonia lasiopus O.Hoffm. (8.7%), Cascabella thevetia( L.)Lippold (4.3%) and Oncoba routledgei Sprague (4.3%).

Conclusion

Meru central district is rich in biodiversity of biopesticides and other medicinal plants and there is need for further pharmacological studies to validate their use as potential drugs for pests and disease control.