GC-MS analysis and evaluation of antimalarial activity of extract and fractions of Icacina trichantha (Icacinaceae) tuber against Plasmodium berghei infected mice.

Aqueous methanol extract of the tuber of Icacina trichantha was prepared using cold maceration and dried in vacuo at 40°C. The extract was purified using solvent-solvent partitioning with n-hexane, dichloromethane, ethyl acetate, n-butanol. n-Hexane fraction was purified using Vacuum Liquid Chromatography, eluting with a gradient of dichloromethane in methanol (9:1, 7:3, 5:5, 0:10, each 500 mL) to obtain four sub-fractions. Acute toxicity study was done using Lorke’s method while in vivo anti-malarial study was carried out using suppressive model. Phytochemical analysis was carried out using standard procedure and most active sub-fraction was subjected to gas chromatography-mass spectroscopy. The extract at doses of 100, 200 and 400 mg/kg caused a significant (p<0.001) increase in percentage suppression of Plasmodium: 91.54 %, 94.48 % and 94.58% respectively. Phytochemical analysis of the extract revealed the presence of alkaloids, tannins, flavonoids saponin, glycoside, terpenoids, phenols, steroids, carbohydrates, reducing sugars. The GC-MS analysis showed the presence of eighteen compounds, the most abundant compound includes 9- octadecenoic acid (Z)-, methyl ester (oleic acid, 15.30%), 9, 12-octadecadienoic acid (Z, Z), methyl ester (linoleic acid, 14.34%). These findings suggest scientific evidence in support to the use of I. trichantha tuber for the management of malaria.