Phytochemical Screening and Mosquito Repellent Activity of the Stem Bark Extracts of Euphorbia Balsamifera (Ait)
The phytochemical screening of extracts from Euphorbia balsamifera was carried out, and the results revealed that the stem bark contains alkaloids, tannins, flavonoids, saponins, glycosides, terpenoids and sterols. The ethanol extract of the stem bark of Euphorbia balsamifera (commonly known as Ayyara in Hausa) was sequentially partitioned with petroleum ether, chloroform, ethyl acetate and methanol. The extracts were respectively labeled EB1, EB2, EB3, and EB4, with the ethanolic extract labeled EB. The extracts, 12.5% and 25% w/v, were tested for repellency against Anopheles gambiae, and the repellent activity was assessed using the human-bait technique. Five volunteers participated in the laboratory tests to ascertain the repellent activity of the extracts, and each volunteer was test with one extract, with each test repeated in triplicate. The chloroform extract labeled EB1-02 was found to be the most active, (97.2% and 100% repellency), while the extract labeled EB1-03 recorded the least activity of 32.4% and 21.6%. It can be concluded that the chloroform extract labeled EB1-02 is responsible for repellent activity of Euphorbia balsamifera.
Keywords: Anopheles gambiae, Euphorbia balsamifera extracts, Human-bait technique, Phytochemicals, Repellency