Evaluation of the effects of Olea europaea L. subsp. africana (Mill.) P.S. Green (Oleaceae) leaf methanol extract against castor oil-induced diarrhoea in mice

Olea europaea L. subsp. africana (Mill.) P.S. Green is widely used in South Africa by traditional medicine practitioners to treat diarrhoea. However, little is known scientifically about this South African species in the treatment of diarrhoea. The main aim of the study therefore was to investigate the antidiarrhoeal effect of the leaf methanol extract of the plant species in mice. The antidiarrhoeal activity of the leaf methanol extract of O. europaea subsp. africana was studied using a castor oil-induced diarrhoeal test. The antipropulsive activity of the plant extract was also investigated using the charcoal meal transit test. Standard methods were used to investigate the acute toxicity and effect of O. europaea subsp. africana on castor oil-induced intraluminal fluid accumulation

Political corruption in Congo Zaïre : its impact on development

vii, 133 leaves ; 28 cm.Includes abstract.Includes bibliographical references (leaves 125-133).In the past decade or so, the "Great Lakes Region" of Sub-Saharan Africa attracted considerable attention from many observers and scholars. In this part of Africa, events have been always influenced by both the political and economic structures led down by the Belgians as colonizers of this region, but also, by the current changes and shifts in the global political economy. As a result, Congo-Zaïre, found itself trapped in one of the worst and consistent crisis ever experienced since it became independent from Belgium in 1960. This study however, will investigate the sources of the "Dire" political corruption and whether there could be any co-existence of corruption and development. The thesis of this study is that the political corruption in Congo-Zaïre has been exacerbated by the support of Mobutu's regime by the West during the Cold War era in Africa. Specifically it is argued that the massive in flows of loans received from the World Bank/IMF in the same period, created an opportunity for the government officials to deviate funds, thus making the state more dependent on the West and legitimizing corruption practices in that country

Pharmacognostic study of 5 medicinal plant species from Western Cape Province (South Africa) for anti-tubercular activity

Includes bibliographical references (leaves 126-140).In our search for new anti-tuberculosis lead molecules, five medicinal plant species, Olea capensis (L.l, Tulbaghia alliacea (L.), Inula graveolens (L.), Leyssera gnaphaloides (L.), and Buddleja saligna (L.) were collected in Cape Town and surrounding area and investigated for antimycobacterial activity following report of their therapeutic use in traditional medicine to treat infectious diseases such as tuberculosis. A bioassay guided fractionation of the acetone/water (4:1) crude extracts of O. capensis (leaves) and T. alliacea (rhizomes) showed no activity against Escherichia coli ATCC 25922, Staphylococcus aureus ATCC 252923, and Mycobacterium aurum A+. In contrast, the orgamc fractions (hexane, dichloromethane) of the acetone/water (4: 1) crude extracts of 1. graveolens, L. gnaphaloides, and B. saligna exhibited significant activity against M. tuberculosis H37Rv, M. avium 25291, M. microti ATCC 19422, and M. scrofulaceum ATCC 19987. The isolation and structure determination of the bioactive led to the identification of pentacyclic triterpenoids, ursolic acid (UA) and oleanolic acid as major antitubercular constituents of B. saligna, L. gnaphaloides, and 1. graveolens. The in vitro cytotoxicity assays of the isolated bioactive constituents showed no cytotoxicity against Chinese Hamster Ovarian (CHO) cells line. Subsequently, given the pharmaceutical value of the above finding, a survey on structure activity of pentacyclic triterpenoids was conducted. It was was found, for instance that selective substitutions at C-3 and/or C-28 and the double bond at UA, OA and betulinic and (1) BA) were made in order to improve anti-tumour and anti-HIV activity. However, thought a great number of modified bioactive pentacyclic triterpenoids is reported, none was tested against Mtb. Therefore, this study also explored a new synthetic route (scheme 1) toward a generation of (5), which may allow improving antitubercular, anti-HIV or anti-tumour activity, and/or specificity

EFFECT OF OLEA EUROPAEA AFRICANA L. (OLEACEAE) LEAF AQUEOUS EXTRACT ON CASTOR OIL-INDUCED DIARRHOEA IN MICE

The leaf aqueous extract of O. europaea ssp. africana L. was tested for antidiarrhoeal activity against castor oil–induced diarrhoea in mice. Acute toxicity studies and phytochemical analysis of O. europaea africana were also carried out. O. europaea ssp. africana significantly reduced the number of diarrhoeal episodes induced by castor oil. O. europaea ssp. africana also significantly decreased the stool mass produced as a result of castor oil-induced diarrhoea and significantly prolonged the onset of the diarrhoea. The number of animals exhibiting diarrhoea over a five hour period was significantly decreased by O. europaea ssp. africana. Similarly, loperamide completely abolished the diarrhoeal episodes and stool mass, and protected the animals against castor oil-induced diarrhoea. The results obtained suggest that the aqueous extract of O. europaea ssp. africana has antidiarrhoeal properties. The relatively high LD50 of 3475 mg/kg (p.o.) obtained with the aqueous extract indicates that the plant species may be safe and/or nontoxic in mice. The phytochemical analysis done on the plant species showed the presence of saponins, tannins, flavonoids, triterpene steroids and reducing sugars