ABSTRACT
Bioactivity-guided fractionation of extracts of roots and leaves of Cajanus cajan afforded 8 compounds: betulinic acid, biochanin A, cajanol, genistein and 2'-hydroxygenistein, longistylin A and C, and pinostrobin. The two stilbenes, longistylin A and C, and betulinic acid showed a moderately high in vitro activity against the chloroquine-sensitive Plasmodium falciparum strain 3D7.
Subject(s)
Antimalarials/pharmacology , Cajanus , Phytotherapy , Plant Extracts/pharmacology , Plasmodium falciparum/drug effects , Animals , Antimalarials/administration & dosage , Antimalarials/therapeutic use , Humans , Malaria, Falciparum/drug therapy , Parasitic Sensitivity Tests , Plant Extracts/administration & dosage , Plant Extracts/therapeutic use , Plant Leaves , Plant RootsABSTRACT
Extracts of the leaves from Vernonia brachycalyx showed in vitro activity against Plasmodium falciparum and promastigotes of Leishmania major. The germacrane dilactone 16,17-dihydrobrachycalyxolide (1) which was previously isolated from the aerial parts of the plant was shown to be the major antiplasmodial principle. An X-ray crystallographic analysis established the absolute configuration and some signals in the NMR spectra were reassigned. 16,17-Dihydrobrachycalyxolide (1) elicited a strong antiplasmodial and antileishmanial activity but also a high toxicity against human lymphocytes.
Subject(s)
Antiprotozoal Agents/pharmacology , Leishmania major/drug effects , Lymphocytes/drug effects , Plant Extracts , Sesquiterpenes, Germacrane/chemistry , Sesquiterpenes, Germacrane/pharmacology , Animals , Antiprotozoal Agents/chemistry , Antiprotozoal Agents/isolation & purification , Cell Survival/drug effects , Humans , Lymphocytes/cytology , Models, Molecular , Molecular Conformation , Molecular Structure , Plant Leaves , Plants, Medicinal , Sesquiterpenes, Germacrane/isolation & purificationABSTRACT
Two alkamides E,E-2,4-octadienamide and E,Z-2,4-decadienamide have been isolated from Phyllanthus fraternus, a plant used in Ghanaian traditional medicine to treat malaria. The compounds possess an alpha, beta, gamma, delta-unsaturated conjugated amide, a feature believed to enhance antiplasmodial activity. By means of an in vitro assay the two alkamides have been shown to possess moderate antiplasmodial activity.
Subject(s)
Amides/pharmacology , Antiprotozoal Agents/pharmacology , Lymphocytes/drug effects , Plants, Medicinal , Amides/chemistry , Amides/isolation & purification , Animals , Antiprotozoal Agents/chemistry , Antiprotozoal Agents/isolation & purification , Humans , Leishmania major/drug effects , Lymphocyte Activation/drug effects , Lymphocytes/immunology , Plasmodium falciparum/drug effectsABSTRACT
A new limonoid was isolated from the bark of Khaya senegalensis and identified as 2,6-dihydroxyfissinolide. The assignments of some signals in the (13)C NMR spectrum of fissinolide have been reversed and the signals of the (1)H NMR spectrum of methyl 3beta-acetoxy-6-hydroxy-1-oxomeliac-14-enoate have been assigned. The limonoids only showed moderate antiprotozoal activities.
ABSTRACT
Previous studies have shown that licochalcone A, an oxygenated chalcone, exhibits antileishmanial and antimalarial activities. The present study was designed to examine the antimalarial activity of an analog of licochalcone A, 2,4-dimethoxy-4'-butoxychalcone (2,4mbc). 2,4mbc inhibited the in vitro growth of both a chloroquine-susceptible (3D7) and a chloroquine-resistant (Dd2) strain of Plasmodium falciparum in a [3H]hypoxanthine uptake assay. The in vivo activity of 2,4mbc was tested in mice infected with Plasmodium berghei or Plasmodium yoelii and in rats infected with P. berghei. 2,4mbc administered either orally, intraperitoneally, or subcutaneously for 5 days protected the mice from otherwise lethal infections of these parasites. 2,4mbc administered orally for 5 days reduced parasitemia in the rats infected with P. berghei. These results demonstrate that 2,4mbc exhibits potent antimalarial activity and might be developed into a new antimalarial drug.
