Evaluation of the anti-proliferative and cytotoxic potentials of fractions of methanol leaf extract of Cnidoscolus aconitifolius

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,