Isolation and characterization of antiplasmodial compounds from Siphonochilus aethiopicus and Aloe ferox and bioavailability of a novel furanoterpenoid

Includes abstract. Includes bibliographical references (leaves 138-162)

Studies on in vitro antiplasmodial activity of cleome rutidosperma

Malaria is a protozoal disease transmitted by the Anopheles mosquito, caused by minute parasitic protozoa of the genus Plasmodium, which infect human and insect hosts alternatively. It affects over 40% of the worldís population, with 120 million cases reported, and about 2 million deaths annually (1). The P. falciparum variety of the parasite accounts for 80% of cases and 90% of deaths caused by malaria. The declining efficacy of classical medication in relation to the rapid increase of parasite resistant strains, mainly of Plasmodium falciparum, as well as the greater resistance of vectors to insecticides, and the difficulty of creating efficient vaccines have led to an urgent need for new efficient antimalarial drugs (2, 3). Natural molecules may provide innovative strategies towards malarial control, hence active research groups are now working to develop new active compounds as an alternative to chloroquine, especially from artemisinin (4, 5), a plant-based antimalaria drug isolated from the Chinese plant Artemisia annua (6). Plants may well, therefore, prove to be the sources of new antimalarial in view of the success with the two important chemotherapeutic agents, quinine and artemisinin, both of which are derived from plants. Cleome rutidosperma (Capparidaceae) is a low-growing herb, up to 70 cm tall, found in waste grounds and grassy places with trifoliate leaves and small, violet-blue flowers, which turn pink as they age. The elongated capsules display the asymmetrical, dull black seeds. The plant is native to West Africa, although it has become naturalized in various parts of tropical America as well as Southeast Asia (7, 8). The diuretic, laxative, anthelmintic, antimicrobial, analgesic, anti-inflammatory, antipyretic, antioxidant and free radical scavenging activities of Cleome rutidosperma were reported earlier by the authors (9-13). The plant is used as antimalarial by the traditional healers in Cameroon and mild antiplasmodial activity of chloroform/methanol (1:1) extract of leaves of Cleome rutidosperma against chloroquine-sensitive (F32) laboratory strain of P. falciparum was reported earlier in Cameroon (14). The present study investigates the in vitro antiplasmodial activity of ethanolic extract and its fractions of aerial parts of Cleome rutidosperma against the chloroquine sensitive (CQS) D10 strain of the parasite, as well as their toxicity against a mammalian cell lines

Antiplasmodial hirsutinolides from Vernonia staehelinoides and their utilization towards a simplified pharmacophore

Please open article to read abstractThis work was financially supported by the Department of Science and Technology which awarded an innovation fund to five South African institutions (The Medical Research Council, South African National Biodiversity Institute, Council for Scientific and Industrial Research, University of Cape Town and University of Pretoria) to scientifically validate South African medicinal plants for the treatment of malaria

Synthesis of novel 2-alkoxy-3-amino-3-arylpropan-1-ols and 5-alkoxy-4-aryl-1,3-oxazinanes with antimalarial activity

A variety of novel syn-2-alkoxy-3-amino-3-arylpropan-1-ols was prepared through LiAlH4-promoted reductive ring-opening of cis-3-alkoxy-4-aryl-beta-lactams in Et2O. The latter gamma-aminoalcohols were easily converted into cis-5-alkoxy-4-aryl-1,3-oxazinanes using formaldehyde in THE Both series of compounds were evaluated against a chloroquine sensitive strain of Plasmodium falciparum (D10), revealing micromolar potency for almost all representatives. Eleven compounds exhibited antimalarial activity with IC50 values of <= 30 mu M, and the majority of these compounds did not show cytotoxicity at the concentrations tested