Mortality and Inhibitory Effects of Aqueous and Methanolic Extracts of Artemisia annua L. on Biomphalaria pfeifferi (Krauss) and Shedding of Cercariae

Abstract

The search for bioactive plants which can be used as non-conventional anthelmintics has received considerable attention in recent times because of the increasing, worldwide development of resistance to synthetic anthelminthes worm populations. However, scientific evidence to validate the use of raw plants materials remain limited. This study evaluated the mortality and inhibitory effects of the crude aqueous and methanolic extract of Artemisia annua L. against the shedding of cercariae of Schistosoma mansoni from Biomphalaria pfeifferi. The phytochemical screening of the plant was done using standard procedure, after which the mortality effects of the plant extracts and effects on the shedding of cercariae from B. pfeifferi snails were assessed for 24 hour of exposure. Methanolic extract with the highest concentration of 1.77mg/µL had an inhibitory effect of 63.06±1.84 while the least concentration with 0.12mg/µL had 22.41±2.17 inhibitory effect. For the aqueous extract, the highest concentration with 2.73mg/µL had an inhibitory effect of  55.75±1.94 while the least concentration of 0.23mg/µL had 21.80±1.45. Inhibitory effect of cercariae in the snail vector was  concentration dependent, and there was significance difference (P<0.05) between the treatment mean when compared with the control group. This study has shown that this plant material has some inhibitory effect on the shedding of of S. mansoni cercariae and toxicityeffect on the B. pfeifferisnails, and can therefore be used for the control of the disease causing agent as well as the vector. Keywords: Artemisia annua, Inhibitory effects, cercariae, Biomphalaria pfeifferi