Antioxidant and anti-proliferative activities of Acalypha fruticosa: Possible elucidated mechanism

This study aimed to investigate the potential anti-oxidant activity of methanol (Aca-M) extract and n-hexane (Aca-H), chloroform (Aca-Ch), ethyl acetate (Aca-E), n-butanol (Aca-B) and aqueous (Aca-A) fractions obtained from the aerial parts of Acalypha fruticosa (Aca) using the 2, 2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging assay. Data obtained revealed that A. fruticosa methanol extract and different fractions inhibited the DPPH radicals in the following descending order: Aca-E >Aca-B >Aca-M >Aca-A >Aca-Ch >Aca-H compared to ascorbic acid. Additionally, in vitro 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium (MTT) assay against MCF-7, HCT-116, HepG-2 and non-cancerous MRC-5 cell lines was performed to determine their selective anti-cancer activity. The Aca-Ch fraction exhibited remarkable cytotoxic activity against all tested cancerous cell lines with IC₅₀ 4.81- 12.2μg/mL, while both Aca-Ch and Aca-H fractions possessed potent cytotoxic activities on HCT-116 (IC₅₀ 4.81 and 10.1, respectively) with negligible harm but selective effect on non-cancerous MRC-5 cells (IC50 20.4 and 85.2, respectively).