Phytochemical screening of Tanzanian medicinal plants. I

Evaluation of in vitro schizontocidal activity of plant parts of Calotropis procera--an ethnobotanical approach

Calotropis procera (Ait.) R.Br. commonly known, as 'Arka' is a popular medicinal plant found throughout the tropics of Asia and Africa and is used in many traditional systems of medicine. Important factors of the various parts of this plant have been widely reported. Good record keeping of subjective and objectively recorded cures by practitioners of traditional medicinal system will help in the establishment of the use of C. procera as an antimalarial plant. It has been attempted to see the effect of crude fractions of its flower, bud and roof against a chloroquine sensitive strain, MRC 20 and a chloroquine resistant strain, MRC 76 of Plasmodium falciparum using the Desjardins method and the effectiveness of its fractions compare better with the CQ sensitive strain than the CQ resistant strain in vitro.

Effect of some Indian herbs on macrophage functions in ochratoxin A treated mice

The effect of Indian herbs namely, Asparagus racemosus, Tinospora cordifolia, Withania somnifera and Picrorhiza kurrooa on the functions of macrophages obtained from mice treated with the carcinogen ochratoxin A (OTA) was investigated. The chemotactic activity of murine macrophages was significantly decreased by 17 weeks of treatment with OTA compared with controls. Production of interleukin-1 (IL-1) and tumor necrosis factor (TNF) was also markedly reduced. Treatment with Asparagus racemosus, Tinospora cordifolia, Withania somnifera and Picrorhiza kurrooa significantly inhibited OTA-induced suppression of chemotactic activity and production of IL-1 and TNF-alpha by macropahges. Moreover, we found that Withania somnifera treated macrophage chemotaxis and that Asparagus racemosus induced excess production of TNF-alpha when compared with controls.

Antiplasmodial activity of four Kenyan medicinal plants

A preliminary antiplasmodial and phytochemical screening of four Kenyan medicinal plants was carried out. The medicinal plants were extracted and tested for in vitro antiplasmodial activity against chloroquine-sensitive (K67) and chloroquine-resistant (ENT36) strains of Plasmodium falciparum. Out of 16 extracts, 12 were active against ENT36 strain while seven were active against K67 strain, that is, IC50 < or = 50 micrograms/ml. The most active extracts on both strains were those of leaves of Phyllanthus reticulatus Poir, and Suregada zanzibariensis Baill. (Euphorbiaceae) with IC50 < or = 10 micrograms/ml. The stembark of Terminalia spinosa Engl. (Combretaceae) and the stems of Dissotis brazzae Cogn. (Melastomataceae) had IC50 < or = 10 micrograms/ml for strains K67 and ENT36, respectively. A preliminary phytochemical analysis of these plants revealed the presence of different classes of primary and secondary metabolites.

Screening Tanzanian medicinal plants for antimalarial activity

Forty-three different plant species commonly used in traditional medicine for the treatment of malaria were selected and screened for their antimalarial activity against Plasmodium falciparum in vitro. Thirteen of the 43 species were obtained directly from traditional healers who use these plants for the treatment of malaria. The other plant species were collected on the basis of ethnomedicinal information in the literature. The plant material was collected from Morogoro, Dar es Salaam and Kagera regions in Tanzania. Fifty-eight plant samples from these 43 plant species, including leaves, roots and stem bark, were investigated. Apart from the crude EtOH extracts, petroleum ether (PE), ethyl acetate (EtAc) and H2O fractions of these extracts were also tested. The in vitro testing revealed that 37% of the investigated plants showed strong antimalarial activity with IC50 values below 10 micrograms/ml. The four most active plants included Cissampelos mucronata, Maytenus senegalensis, Salacia madagascariensis and Zanthoxylum chalybeum.

Plants used in traditional medicine in eastern Tanzania. VI. Angiosperms (Sapotaceae to Zingiberaceae)

Fifty-three Angiosperm species (Sapotaceae to Zingiberaceae), which are used by traditional healers in five regions of Eastern Tanzania (Coast, Dar es Salaam, Kilimanjaro, Morogoro and Tanga) are listed. For each species, the botanical name, vernacular name, collection number, locality, habit, geographic distribution and medicinal uses are given. Additionally, information from the literature on medicinal uses, chemical constituents and pharmacological effects are also provided. Data analysis and conclusions to cover all the six parts of the papers previously published are presented.

Plants used in traditional medicine in eastern Tanzania. V. Angiosperms (Passifloraceae to Sapindaceae)

Sixty-one Angiosperms (Passifloraceae to Sapindaceae) are listed, which are used by traditional healers in five regions of Eastern Tanzania, namely, Coast, Dar es Salaam, Kilimanjaro, Morogoro and Tanga. For each species listed, the botanical name, vernacular name, collection number, locality, habit, distribution and medicinal uses are given. Additionally, information from the literature on medicinal uses, chemical constituents and pharmacological effects are also provided.

Plants used in traditional medicine in eastern Tanzania. III. Angiosperms (Euphorbiaceae to Menispermaceae)

Seventy-seven Angiosperms (Euphorbiaceae to Menispermaceae) are listed, which are used by traditional healers in five regions of Eastern Tanzania; namely, Coast, Dar es Salaam, Kilimanjaro, Morogoro and Tanga. For each species listed, the botanical name, vernacular name, collection number, locality, habit, distribution and medicinal uses are given. Additionally, information from the literature on medicinal uses, chemical constituents and pharmacological effects is also provided.

Plants used in traditional medicine in eastern Tanzania. II. Angiosperms (Capparidaceae to Ebenaceae)

Sixty-nine plants are listed, which are used by traditional healers in five regions of Eastern Tanzania, Coast, Dar es Salaam, Kilimanjaro, Morogoro and Tanga. For each species the botanical name, vernacular name, collection number, locality, habit, distribution and medicinal uses are given. Results of a literature survey on medicinal uses, isolated constituents, and pharmacological effects are also provided.

Public health in pre-colonial east-central Africa

This study is the first of its kind to suggest that a rich public health tradition existed in east-central Africa before the twentieth century, and that the tradition can be reconstructed historically. It breaks with earlier studies of public health history for the region in that it does not define public health on the basis of western institutions and activities. The definition of public health that is used in this study makes a simple equation between politics and medicine. It includes all activities that ruling authorities undertake to promote the well-being of the societies over which they have charge. Thus rainmaking and sorcery control, the principal services in traditional African societies, are the focus of this study. Evidence is presented here of the control exercised by kings, chiefs, priests over these services in various societies located in southeastern Zaire, southern Tanzania, Zambia, Malawi, northern Mozambique, and Zimbabwe. The cases are all set in the pre-colonial period, before the twentieth century and the beginning of most written records. The evidence is derived primarily, though not exclusively, from non-written sources, such as archaeology, linguistic, and ethnographic records. The best data are those that come from cultural exchanges between people, for historical records are created in this way. Therefore, the cases discussed here all involve contacts between immigrant and autochthonous groups. The political histories of these contacts are already known. What this study does is link up those traditions with independently-acquired evidence of change in medical traditions. Political change often, but not always, led to change in public health institutions. The control of ruling elites over health services is thus made apparent by the manner in which new medical institutions were implanted when new political authorities arose.