Merlin Lincoln Kwao Mensah

Medicinal plants and finished marketed herbal products used in the treatment of malaria in the Ashanti region, Ghana

ETHNOPHARMACOLOGICAL RELEVANCE Ethnobotanical survey was performed to document medicinal plants employed in the management of malaria in the Bosomtwe and Sekyere East Districts of the Ashanti Region (Ghana), in comparison with the plant ingredients in herbal antimalarial remedies registered by the Ghana Food and Drug Administration. MATERIALS AND METHODS Two hundred and three (203) herbalists from 33 communities within the two districts were interviewed on medicinal plants they use to manage malaria. A literature search was made to determine already documented plants. In addition, 23 finished marketed herbal products indicated for the management of malaria were identified and their labels examined to find out which of the plants mentioned in our survey were listed as ingredients and whether these products are in anyway regulated. RESULTS Ninety-eight (98) species of plants were cited for the management of malaria. In comparison with literature citations, 12 (12.2%) species were reported for the management of malaria for the first time and 20 (20.4%) others for the first time in Ghana. Twenty-three (23) finished marketed herbal antimalarial products examined contained aerial or underground parts of 29 of the plants cited in our survey as ingredients. Twenty-two (22) of these products have been registered by the Ghana Food and Drugs Authority, four (4) of which were included in the recommended herbal medicine list for treating malaria in Ghana. CONCLUSION This study provides new additions to the inventory of medicinal plants used for the management of malaria and reports the commercial availability and regulation of finished marketed labelled herbal products intended for the treatment of malaria in Ghana.

Chemical Diversity of Lippia multiflora Essential Oils from West Africa

Abstract The essential oil content, composition and the physicochemical properties of Lippia multiflora leaves from twelve different regions in Ghana were characterized in this study. The Ghanaian oils showed a significant variability in their chemical composition and five chemotypes were identified. The oil from Aframso Bridge was yellow with a refractive index (RI) of 1.4853, density (DE) of 0.894 and was dominated by linalool (29%) and germacrene D (28%) with fresh, and slightly medicinal and spicy aroma. Ghanaian samples from Seikwa, Buem Nsuta and Golokwati were characterized by high levels of sesquiterpenes (45–70%). The aroma was medicinal/herbaceous and the color was typically yellow, except the oil from Seikwa which was dark orange-yellow, RI ranging from 1.4920 to 1.5043 and DE 0.893 to 0.93 D. The oils from Nyankpala, Sari, Amantin, Atebubu and Kobre contained high levels of aromatic monoterpenes (p-cymene 14–19%, thymol 30–40%, and thymyl acetate 14–17%). The oils were characterized as spicy and the color ranged from dark yellow (Nyankpala, Sari and Kobre) to yellow (Atebubu and Amantin) (RI 1.4969 to 1.5020, DE 0.9207 to 0.9344). The oil from Ho showed lower levels of aromatic monoterpenes and higher levels of farnesol, the oil was yellow and aroma woody/camphoraceous (1.492 RI, 0.893 D). In contrast, oils from Nsawkaw and Kofiase-Kubesiase were composed of high amounts of 1,8-cineole (43–47%), sabinene (12–15%, respectively), and were light yellow (RI 1.4695 to 1.4712, DE 0.8995 to 0.9002). A cluster analysis was performed for comparison and characterization of L. multiflora oils from Ghana other 33 oils from 10 African countries. The oils from Ghana with these five chemotypes appeared to be the most diverse oils in Sub-Saharan Africa.

Antiinflammatory properties of the stem-bark of Anopyxis klaineana and its major constituent, methyl angolensate.

Anopyxis klaineana (Pierre) Engl. (Rhizophoraceae) is one of the reputed West African folkloric medicines that has never been investigated for its pharmacological effects or phytochemical constituents. In the present study, the antiinflammatory properties of the stem‐bark extracts were evaluated using the carrageenan‐induced paw oedema model in chicks. The petroleum ether, ethyl acetate and methanol extracts all showed a time and dose‐dependent antiinflammatory effect over the 5‐h observation period. Phytochemical analysis of the most active extract (methanol extract) yielded the principal constituent that was identified as methyl angolensate through extensive spectroscopic and X‐ray analysis studies. Although slightly less potent (ED50, 4.05 ± 0.0034 mg/kg, orally) than the positive control, diclofenac (ED50, 2.49 ± 0.023, intraperitoneally n = 5), this first ever compound isolated from A. klaineana showed promising antiinflammatory activity that may account to some of the reported medicinal uses of the plant. Copyright

The Antimalarial Potential of Three GhanaianMedicinal Plants

Objective: Malaria is a major public health problem in Ghana and many indigenes, especially those in rural areas, resort to the use of medicinal plants to treat the disease. The plants: Persea americana Mill. (Lauraceae), Theobroma cacao L. (Malvaceae) and Tridax procumbens (L.) L. (Compositae) are used solely or in combination with other medicinal plants to manage malaria and its associated conditions. The leaves of the plants which are normally the main parts employed, were studied for their phytochemistry and antiplasmodial activity to establish their chemical profile and verify the antimalarial claim. Methods: Plant materials were subjected to basic phytochemical screening to identify the major secondary metabolites. The aqueous extracts were evaluated against chloroquine-sensitive 3D7 P. falciparum and chloroquine-resistant W2 P. falciparum strains, using the fluorescence-based SYBR® green I method to determine their antiplasmodial activity. Results: Basic phytochemical screening of the leaves revealed the presence of tannins, flavonoids and alkaloids in all three plant materials. T. cacao and P. americana, in addition, contained purine base alkaloids, triterpenoids including saponins. The aqueous extracts of the leaves showed antiplasmodial activity against the chloroquine-sensitive 3D7 P. falciparum (9.50 ± 1.38 ≤ IC50 ≤ 10.15 ± 0.45 µg/mL) and against chloroquine-resistant W2 P. falciparum strains (6.40 ± 1.94 ≤ IC50 ≤ 44.94 ± 1.12 µg/mL). The aqueous extract of T. cacao was the most active and was more active against W2 than 3D7 P. falciparum. Only T. procumbens displayed cytotoxicity (CC50<25 µg/mL). Conclusion: T. cacao, T. procumbens and P. americana possess antiplamodial activity. The activity illustrates their antimalarial potential, and provides rationale for their use in traditional malaria therapy in Ghana. It thus paves the way for further study of these plants for antiplasmodial lead compound(s).

Pharmacognostic standardisation of Hilleria latifolia (Lam.) H. Walt. (Phytolaccaceae)

ABSTRACT Objective To establish the pharmacognostic characters for the correct identification and quality control of Hilleria latifolia (H. latifolia), an important herb in Ghanaian folklore medicine, for the treatment of infections, pain and inflammation. Methods The macro-morphological, qualitative and quantitative microscopic features, physicochemical and phytochemical features of the medicinally used parts of H. latifolia were evaluated using standard methods. Results The plant has simple, alternate leaves with entire margin. The lamina is ovate to broadly lanceolate with an acuminate apex. It is hypostomatic with anomocytic stomata. The plant contains abundant prismatic crystals in all parts. Starch grains abound in the roots. The quantitative indices of the leaf and physicochemical parameters have also been established. Conclusions The pharmacognostic features established in this study may be used as part of the pharmacopoeial standard for the correct identification and quality control of H. latifolia.

Antileishmanial and Trypanocidal Activities of Extracts and Aporphine Alkaloids Isolated from Monodora Genus (Annonaceae)

Leishmaniasis and trypanosomiasis are protozoan diseases caused respectively by the kinetoplastid protozoan Leishmania parasites transmitted by the female phlebotomine sandflies and Trypanosoma parasites transmitted by the tsetse fly. In the search for agents from tropical medicinal plants to treat these two neglected tropical diseases, serially extracted petroleum ether, dichloromethane and methanol extracts of the leaves of Monodora crispata and Monodora brevipes, and eleven aporphines alkaloids isolated from the dried powdered leaves of the two plants were evaluated against Leishmania donovani promastigotes and Trypanosoma brucei brucei trypomastigotes. The extracts of both plants and the isolated compounds displayed varied levels of antiprotozoal activities. The oxoaporphine compounds, (+)-anolobine (7) and (+)-listeferine (8), exerted the most significant activity against L. donovani (IC50: 14.59 μM) and T. brucei brucei (LC100: 50.02 μM) respectively. This is the first report on the antiprotozoal activity of the isolated compounds. The results offer potential for further studies of the oxoaporphines for enhanced antiprotozoal activity.