Evaluation of the anti-proliferative and cytotoxic potentials of fractions of methanol leaf extract of <i>Cnidoscolus aconitifolius</i>

Abstract

The partitioned aqueous and chloroform fractions obtained from the methanol extract of the leaf of Cnidoscolus aconitifolius were examined for anti-proliferative (1-30 mg/mL) and cytotoxic activities (20-400 μg/mL) using the seed radicle inhibition and tadpole mortality assays over a period of 24 and 96 h respectively. The vacuum liquid  chromatographic sub-fractions of the active chloroform fraction weresimilarly evaluated at 1-10 mg/mL and 5-20 μg/mL concentrations respectively. At 100 μg/mL the chloroform fraction produced 86.67 % mortality which increases to 100 % at 400 μg/mL where the aqueous fraction gave 36.67 %. The potency was further increased as the VLC sub-fractions C4-C6, gave 33 % cytotoxicity at 5 μg/mL and which later increased to 100 % at 10 μg/mL. At the end of 96 h, the control seed had average length of 32.32 ± 2.73 mm compared to 1.92 ± 0.36 and 0.52 ± 0.36 mm observed in the seeds treated with 20 and 30 μg/mL of the chloroform fraction indicating 94.01 and 98.39 % inhibition where as there was total radicle growth inhibition (100 %) of seeds treated with 5 mg/mL of the active VLC sub-fractions (C1-3, C4-C6 and C7). The results showed a significant cytotoxic and growth inhibitory effects of the plant extract, particularly the chloroform fraction and its sub-fractions which further corroborate the folkloric use of the plant in treating cancer. However, further chromatographic analysis of the active VLC  sub-fraction and their respective biological studies using cancer cell-lines are needed to support this.

Keywords: Cnidoscolus aconitifolius, Sorghum bicolor, anti-proliferative, cytotoxicity, methanol extract, aqueous fraction, chloroform extract , vacuum liquid chromatography,