Anti-plasmodial activity and toxicity of extracts of plants used in traditional malaria therapy in Meru and Kilifi Districts of Kenya

• Published in: Journal of ethnopharmacology Vol. 106; no. 3; pp. 403 - 407
• Main Authors: Kirira, P.G., Rukunga, G.M., Wanyonyi, A.W., Muregi, F.M., Gathirwa, J.W., Muthaura, C.N., Omar, S.A., Tolo, F., Mungai, G.M., Ndiege, I.O.
• Format: Journal Article
• Language: English
• Published: Shannon Elsevier Ireland Ltd 19-07-2006; Elsevier
• Subjects: Acacia nilotica; Animals; Anti-malarial plants; Anti-plasmodial activity; antimalarials; Antimalarials - administration & dosage; Antimalarials - pharmacology; Antimalarials - therapeutic use; antiprotozoal agents; Artemia - drug effects; Azadirachta; Azadirachta indica; Biological and medical sciences; Brine shrimp toxicity; Carissa; Carissa edulis; chemical constituents of plants; cytotoxins; ethnobotany; Extracts; Fagaropsis angolensis; General pharmacology; Harissonia abyssinica; herbal medicines; Humans; Kenya; malaria; Malaria, Falciparum - drug therapy; Medical sciences; Medicinal plants; medicinal properties; Medicine, African Traditional; Myrica salicifolia; Neoboutonia macrocalyx; Parasitic Sensitivity Tests; Pharmacognosy. Homeopathy. Health food; Pharmacology. Drug treatments; Phytotherapy; plant extracts; Plant Extracts - administration & dosage; Plant Extracts - pharmacology; Plant Extracts - therapeutic use; Plants, Medicinal; Plasmodium falciparum; Plasmodium falciparum - drug effects; Strychnos heningsii; traditional medicine; Withania somnifera; Zanthoxylum usambarensis; Kenya; Africa; Medicinal plants; Extracts; Plasmodium falciparum; Brine shrimp toxicity; Anti-plasmodial activity; Anti-malarial plants; Antimalarial; Protozoal disease; Toxicity; Extract; Medicinal plant; Crustacea; Folk medicine; Branchiopoda; Protozoa; Apicomplexa; Artemia salina; Malaria; Pharmacognosy; Parasitosis; Infection; Treatment; Arthropoda; Plant origin; Parasiticide; Invertebrata
• ISSN: 0378-8741; 1872-7573
• DOI: 10.1016/j.jep.2006.01.017

The methanol and aqueous extracts of 10 plant species (
Acacia nilotica,
Azadirachta indica,
Carissa edulis,
Fagaropsis angolensis,
Harrissonia abyssinica,
Myrica salicifolia,
Neoboutonia macrocalyx,
Strychnos heningsii,
Withania somnifera and
Zanthoxylum usambarensis) used to treat malaria in Meru and Kilifi Districts, Kenya, were tested for brine shrimp lethality and in vitro anti-plasmodial activity against chloroquine-sensitive and chloroquine-resistant strains of
Plasmodium falciparum (NF54 and ENT30). Of the plants tested, 40% of the methanol extracts were toxic to the brine shrimp (LD
50
<
100
μg/ml), while 50% showed in vitro anti-plasmodial activity (IC
50
<
100
μg/ml). The methanol extract of the stem bark of
N. macrocalyx had the highest toxicity to brine shrimp nauplii (LD
50 21.04
±
1.8
μg/ml). Methanol extracts of the rest of the plants exhibited mild or no brine shrimp toxicity (LD
50
>
50
μg/ml). The aqueous extracts of
N. macrocalyx had mild brine shrimp toxicity (LD
50 41.69
±
0.9
μg/ml), while the rest were lower (LD
50
>
100
μg/ml). The methanol extracts of
F. angolensis and
Zanthoxylum usambarense had IC
50 values <6
μg/ml while the aqueous ones had values between 6 and 15
μg/ml, against both chloroquine-sensitive and resistant
P. falciparum strains. The results support the use of traditional herbs for anti-malarial therapy and demonstrate their potential as sources of drugs.