M. Fawzi Mahomoodally

Traditional Medicines in Africa: An Appraisal of Ten Potent African Medicinal Plants

The use of medicinal plants as a fundamental component of the African traditional healthcare system is perhaps the oldest and the most assorted of all therapeutic systems. In many parts of rural Africa, traditional healers prescribing medicinal plants are the most easily accessible and affordable health resource available to the local community and at times the only therapy that subsists. Nonetheless, there is still a paucity of updated comprehensive compilation of promising medicinal plants from the African continent. The major focus of the present review is to provide an updated overview of 10 promising medicinal plants from the African biodiversity which have short- as well as long-term potential to be developed as future phytopharmaceuticals to treat and/or manage panoply of infectious and chronic conditions. In this endeavour, key scientific databases have been probed to investigate trends in the rapidly increasing number of scientific publications on African traditional medicinal plants. Within the framework of enhancing the significance of traditional African medicinal plants, aspects such as traditional use, phytochemical profile, in vitro, in vivo, and clinical studies and also future challenges pertaining to the use of these plants have been explored.

Euphorbia denticulata Lam.: A promising source of phyto-pharmaceuticals for the development of novel functional formulations.

In this study, Methanolic extracts of Euphorbia denticulata parts (flowers, leaf, stem, and mix of aerial parts) were assessed for a panoply of bioactivities. Inhibitory potential against key enzymes involved in diabetes (α-glucosidase and α-amylase), obesity (pancreatic lipase), neurodegenerative diseases (cholinesterases), and hyperpigmentation (tyrosinase) was evaluated. The antioxidant and antibacterial properties were also assessed. The total phenolic, flavonoid, and phytochemical profile were established using HPLC/DAD and molecular modelling studies on specific target compounds were performed in silico. The flower extract was found to be rich in phenolics and flavonoids, (60.11±1.40mgGAE/g and 42.04±0.16mgRE/g respectively), which tend to correlate with the high radical scavenging activity of this extract (120.34±3.33mgTE/g and 165.42±2.16mgTE/g for DPPH and ABTS respectively). Catechin, epicatechin, gallic acid, p-OH-Benzoic acid, rosmarinic acid, and epigallocatechin gallate, found in significant abundance in the extracts were assessed using molecular modelling with the aim to study their docking properties on a set of six enzymes used in this study. The extracts were moderately effective with MIC values ranging between 1.56 to 6.25mg/ml, but potent growth inhibitors of MRSA strains. Results amassed herein can be used as a stimulus for further studies geared towards the development of novel phyto-pharmaceuticals.

Ethnomedicinal application of native remedies used against diabetes and related complications in Mauritius.

ETHNOPHARMACOLOGICAL RELEVANCE Notoriously, the tropical island of Mauritius has one of the highest prevalence of diabetes worldwide and the economic burden associated with it is alarming. The use of native remedies (NRs) is well anchored in the local culture and it continues to be the cornerstone of therapy for diabetic patients. However, there is currently a dearth of updated primary data on NRs used by Mauritians against diabetes and diabetes related complications (DRCs). This study was therefore designed to record, analyze and document orally transmitted ethnopharmacological knowledge from diabetic patients and traditional medicine practitioners (TMPs) in Mauritius concerning NRs commonly used against diabetes and DRCs which might open new avenues to initiate novel antidiabetic drugs discovery. MATERIALS AND METHODS Data was collected following interviews from diabetic patients (n=328) and TMPs (n=20). Eleven quantitative indexes, namely informant consensus factor (FIC), fidelity level (FL), use value (UV), relative frequency of citation (RFC), relative importance (RI), cultural importance index (CII), index of agreement on remedies (IAR), cultural agreement index (CAI), quality use value (QUV), quality use agreement value (QUAV) and ethnobotanicity index (EI) were calculated. Statistical analysis such as Pearson correlation and Chi-squared test were performed to determine any association. RESULTS A total of 111 plant species distributed over 56 families, 30 polyherbal formulations and 16 animal species were documented to be traditionally used against diabetes and DRCs. For the first time 8 endemic plants have been recorded to be used against diabetes and DRCs from Mauritius. The most encountered medicinal plant family was Asteraceae. According to the EI, 16.2% of the native plants in Mauritius were used against diabetes and DRCs. As far as we know, Vangueria madagascariensis, Apium graveolens, Petroselinum crispum and Rubus alceifolius with high RFC values are recorded against diabetes and DRCs for the first time. Sociodemographic characteristics (age, gender, income, religious belief, education and residence) were found to significantly (p<0.05) influence the use of NRs. The average FIC for all ailments for plant and animal products were 0.94 and 0.87 respectively. Bryophyllum pinnatum, a native plant to Mauritius scored a high FL value (100%) used against diabetic neuropathy, Allium sativum had the highest RI value (2.00) due to its versatility, Aloe vera had the highest RFC (0.61), the CII (0.640) and the highest CAI value (0.635), Psidium guajava had the highest QUAV (0.961) which indicates its high bioactivity and Allium cepa was reported as the most effective plant species (QUV=0.965). According to UV, the most important species was Morinda citrifolia (1.21). Panoply of animal products were reported whereby fish (39.7%) was recorded as the most utilised zootherapy and Salmo salar scored the highest FL (100%) for diabetes. Some animal species (n=14) not previously documented against diabetes and DRCs are reported in the present study. CONCLUSION Our present investigation revealed that the use of NRs constitutes the common legacy of Mauritians and despite the penetration of allopathic medicine; NRs continue to play a crucial role in the primary health care system of Mauritius. To this effect, it is of uttermost importance to record this knowledge before it disappears. In addition, further experimental investigations are required to elucidate the pharmacological properties of the reported medicinal flora and fauna of Mauritius.

Ethnopharmacological survey of native remedies commonly used against infectious diseases in the tropical island of Mauritius

ETHNOPHARMACOLOGICAL RELEVANCE Infectious diseases (IDs) still remain a major cause of mortality and morbidity worldwide. This study has been geared to gather primary ethnopharmacological information on common native remedies (NRs) used to treat and/or manage common infectious diseases from different regions of Mauritius, a tropical multicultural island in the Indian Ocean. Given the dearth of updated information on traditional medicine of Mauritius, this work can provide an opportunity to establish valuable primary information on the different NRs used by the local people and hence open new perspectives for further pharmacological research. AIM OF THE STUDY To collect, preserve and document primary ethnopharmacological data from the local population concerning NRs commonly used against IDs in the tropical island of Mauritius. MATERIALS AND METHODS Face to face interviews were conducted with Mauritians and herbalists (n=307) using a semi-structured questionnaire. Quantitative ethnobotany parameters such as informant consensus factor (F(IC)), fidelity level (FL), use value (UV) and variety of use (VU) were used for herbal and animal products. Statistical analysis such as Pearson correlation and Chi-squared test were performed to delineate any association. RESULTS It was found that 94.8% of the local people claimed that managing IDs with NRs was part of their culture and have been using it since childhood. A total of 39 plant species belonging to 24 families and 9 animal species were reported to be traditionally used in the formulation of herbal remedies and animal products, respectively. Sociodemographic characteristics (gender, age, place of residence and income) had a significant (p<0.01) impact on the use of these NRs. The most relevant family contributing much to the medicinal flora was Zingiberaceae (No of citation=301). The average F(IC) for all ailments for medicinal plants and animal products were 0.963 and 0.972, respectively. Acalypha indica L. had the highest FL (0.83) for skin and subcutaneous tissue problems. Panoply of animal products (Anguilla japonica, Periplaneta americana and Helix aspersa) were culturally used, whereby products from Bos taurus, (42.0%) were the most utilized zootherapy. Other remedies used in concurrence with herbal and animal products involved cultural rituals and prayers that were never reported in previous studies. Therapeutic properties of some herbal remedies reported correlated to some extent with those of previous studies while others have open potential perspectives for further research as their chemistry and pharmacology have not been published. CONCLUSIONS Given the plethora of novel information obtained from the present survey, it is obvious that the indigenous population still relies to a great extent on NRs which need to be preserved and used sustainably. Nonetheless, further research is needed to probe the possible active constituents that could be the basis of an evidence based investigation to discover new drugs.

Ethnopharmacological analysis of medicinal plants and animals used in the treatment and management of pain in Mauritius

ETHNOPHARMACOLOGICAL RELEVANCE Pain is a multi-faceted and multi-factorial condition which is challenging to manage and treat. Conventional therapies such as analgesics, Non-steroidal anti-inflammatory drugs (NSAIDs), and corticosteroids amongst others have been successful to some extent in its management and treatment. Nonetheless, such therapies tend to be accompanied by undesirable effects and have a limited therapeutic range. Consequently, there is a pressing need to probe for novel analgesic and anti-nociceptive drugs from traditional medicines (TM). This study was designed to record, document and analyze herbal and animal-based therapies used for the management and treatment of pain in the tropical of Mauritius. MATERIALS AND METHODS Data was collected via face-to-face interviews with TM users (n=332) and practitioners (n=20). Seven quantitative ethnopharmacological indexes, namely family use value (FUV), use value (UV), informant agreement ratio (IAR), relative frequency of citation (RFC), fidelity level (FL), relative importance (RI) and ethnobotanicity index (EI) were calculated. RESULTS A total of 79 plant species distributed within 40 families and 20 polyherbal preparations was recorded. Interestingly, 6 indigenous/endemic plants have been reported for the first time to be in common use for pain management and treatment in Mauritius. The most significant biologically important plant family was Xanthorrhoeaceae with highest FUV. The species which ranked highest according to its UV was Morinda citrifolia L. Morinda citrifolia L. and Ricinus communis L. also scored the highest RFC. The IAR values for the disease categories were high (0.95-0.97). Based on EI, plants species which are known to be useful in TM accounted for 11.5% of the total flora in Mauritius. Coix lacryma-jobi L. (FL=100%) had highest FL for lower back ache. Morinda citrifolia L. scored highest on most of the quantitative indices calculated including RI, which is endorsed by extensive documentation on its versatility and particularly its anti-nociceptive properties. Seven animal species were recorded to be in common use. CONCLUSION The present ethnopharmacological study revealed a panoply of TM to be in common use for pain management and treatment in Mauritius. This study has documented for the first time medicinal plants and animal species with potential analgesic and/or anti-nociceptive properties. This study has therefore provided important baseline primary data for the discovery of new lead molecules for drug development geared towards pain management and treatment.

Inhibitory Potential of Five Traditionally Used Native Antidiabetic Medicinal Plants on α-Amylase, α-Glucosidase, Glucose Entrapment, and Amylolysis Kinetics In Vitro

Five traditionally used antidiabetic native medicinal plants of Mauritius, namely, Stillingia lineata (SL), Faujasiopsis flexuosa (FF), Erythroxylum laurifolium (EL), Elaeodendron orientale (EO), and Antidesma madagascariensis (AM), were studied for possible α-amylase and α-glucosidase inhibitory property, glucose entrapment, and amylolysis kinetics in vitro. Only methanolic extracts of EL, EO, and AM (7472.92 ± 5.99, 1745.58 ± 31.66, and 2222.96 ± 13.69 μg/mL, resp.) were found to significantly (P < 0.05) inhibit α-amylase and were comparable to acarbose. EL, EO, AM, and SL extracts (5000 μg/mL) were found to significantly (P < 0.05) inhibit α-glucosidase (between 87.41 ± 3.31 and 96.87 ± 1.37% inhibition). Enzyme kinetic studies showed an uncompetitive and mixed type of inhibition. Extracts showed significant (P < 0.05) glucose entrapment capacities (8 to 29% glucose diffusion retardation index (GDRI)), with SL being more active (29% GDRI) and showing concentration-dependent activity (29, 26, 21, 14, and 5%, resp.). Amylolysis kinetic studies showed that methanolic extracts were more potent inhibitors of α-amylase compared to aqueous extracts and possessed glucose entrapment properties. Our findings tend to provide justification for the hypoglycaemic action of these medicinal plants which has opened novel avenues for the development of new phytopharmaceuticals geared towards diabetes management.

The Therapeutic Potential of Medicinal Foods

Pharmaceutical and nutritional sciences have recently witnessed a bloom in the scientific literature geared towards the use of food plants for their diversified health benefits and potential clinical applications. Health professionals now recognize that a synergism of drug therapy and nutrition might confer optimum outcomes in the fight against diseases. The prophylactic benefits of food plants are being investigated for potential use as novel medicinal remedies due to the presence of pharmacologically active compounds. Although the availability of scientific data is rapidly growing, there is still a paucity of updated compilation of data and concerns about the rationale of these health-foods still persist in the literature. This paper attempts to congregate the nutritional value, phytochemical composition, traditional uses, in vitro and in vivo studies of 10 common medicinal food plants used against chronic noncommunicable and infectious diseases. Food plants included were based on the criteria that they are consumed as a common food in a typical diet as either fruit or vegetable for their nutritive value but have also other parts which are in common use in folk medicine. The potential challenges of incorporating these medicinal foods in the diet which offers prospective opportunities for future drug development are also discussed.

Traditional medicinal herbs and food plants have the potential to inhibit key carbohydrate hydrolyzing enzymes in vitro and reduce postprandial blood glucose peaks in vivo.

We hypothesized that some medicinal herbs and food plants commonly used in the management of diabetes can reduce glucose peaks by inhibiting key carbohydrate hydrolyzing enzymes. To this effect, extracts of Antidesma madagascariense (AM), Erythroxylum macrocarpum (EM), Pittosporum senacia (PS), and Faujasiopsis flexuosa (FF), Momordica charantia (MC), and Ocimum tenuiflorum (OT) were evaluated for α-amylase and α-glucosidase inhibitory effects based on starch-iodine colour changes and PNP-G as substrate, respectively. Only FF and AM extracts/fractions were found to inhibit α-amylase activity significantly (P < 0.05) and coparable to the drug acarbose. Amylase bioassay on isolated mouse plasma confirmed the inhibitory potential of AM and FF extracts with the ethyl acetate fraction of FF being more potent (P < 0.05) than acarbose. Extracts/fractions of AM and MC were found to inhibit significantly (P < 0.05) α-glucosidase activity, with IC50 comparable to the drug 1-deoxynojirimycin. In vivo studies on glycogen-loaded mice showed significant (P < 0.05) depressive effect on elevation of postprandial blood glucose following ingestion of AM and MC extracts. Our findings tend to provide a possible explanation for the hypoglycemic action of MC fruits and AM leaf extracts as alternative nutritional therapy in the management of diabetes.

New Insights in Staging and Chemotherapy of African Trypanosomiasis and Possible Contribution of Medicinal Plants

Human African trypanosomiasis (HAT) is a fatal if untreated fly-borne neuroinflammatory disease caused by protozoa of the species Trypanosoma brucei (T.b.). The increasing trend of HAT cases has been reversed, but according to WHO experts, new epidemics of this disease could appear. In addition, HAT is still a considerable burden for life quality and economy in 36 sub-Saharan Africa countries with 15–20 million persons at risk. Following joined initiatives of WHO and private partners, the fight against HAT was re-engaged, resulting in considerable breakthrough. We present here what is known at this day about HAT etiology and pathogenesis and the new insights in the development of accurate tools and tests for disease staging and severity monitoring in the field. Also, we elaborate herein the promising progresses made in the development of less toxic and more efficient trypanocidal drugs including the potential of medicinal plants and related alternative drug therapies.Human African trypanosomiasis (HAT) is a fatal if untreated fly-borne neuroinflammatory disease caused by protozoa of the species Trypanosoma brucei (T.b.). The increasing trend of HAT cases has been reversed, but according to WHO experts, new epidemics of this disease could appear. In addition, HAT is still a considerable burden for life quality and economy in 36 sub-Saharan Africa countries with 15–20 million persons at risk. Following joined initiatives of WHO and private partners, the fight against HAT was re-engaged, resulting in considerable breakthrough. We present here what is known at this day about HAT etiology and pathogenesis and the new insights in the development of accurate tools and tests for disease staging and severity monitoring in the field. Also, we elaborate herein the promising progresses made in the development of less toxic and more efficient trypanocidal drugs including the potential of medicinal plants and related alternative drug therapies.

Ethnopharmacological analysis of medicinal plants used against non-communicable diseases in Rodrigues Island, Indian Ocean

ETHNOPHARMACOLOGICAL RELEVANCE Rodrigues is an autonomous outer island that form part of the Republic of Mauritius and one of three islands that constitute the Mascarene archipelago in the Indian Ocean. Though herbal medicine is in common use in Rodrigues, there has been no ethnopharmacological study to document quantitatively such traditional practise particularly against non-communicable diseases (NCD) which is currently a growing major health issue on the island. The aim of the present study was to collect, analyse and document traditionally used medicinal plants (MP) from key informants and traditional medicine practitioners (TMP) in the tropical island of Rodrigues to treat and/or manage common NCD. MATERIALS AND METHODS Data was collected via face-to-face interviews with MP users (n=113) and TMP (n=9). Seven quantitative ethnopharmacological indices, namely family use value (FUV), use value (UV), informant agreement ratio (IAR), relative frequency of citation (RFC), fidelity level (FL), relative importance (RI) and ethnobotanicity index (EI) were calculated. RESULTS Hundred and three plants belonging to 55 families were recorded for the treatment and/or management of 27 different NCD. Three of the MP (Terminalia bentzoë (L.) L.F, Sarcostemma cf. adontolepis Balf.f. and Clerodendrum laciniatum Balf.f.) recorded are endemic to Rodrigues and 2 (Carissa xylopicron Thouars., Phyllanthus casticum Willemet f.) endemic to the Mascarene Islands. The most solicited MP family was Asteraceae with a total of 8 species. Citrus aurantifolia (Christm.) Swingle scored the highest RFC (RFC=1.02) value. Ten plants were found to score 100% FL and the highest IAR (0.98) was observed for the disease category of certain conditions originating in the perinatal period. Arecaceae scored the highest FUV value and Ayapana triplinervis (Vahl) R.M. King et H.Rob highest UV (UV= 2.72). CONCLUSION Given the dearth of updated information on traditional medicine of Rodrigues, this study can provide an opportunity to establish valuable primary information on the different MP used by the local people and hence can open new perspectives for further pharmacological research.