Antioxidant and cytotoxicity to liver cancer HepG2 cells in vitro of Korarima (Aframomumcorrorima (Braun) PCM Jansen) seed extracts

This study examined the total phenolic contents, in vitroantioxidant activity and anti-cancer effect of petroleum ether and aqueous: methanol (20:80, v/v) seed extracts of Aframomum corrorima (Ethiopian cardamom). The aqueous methanol extract contained higher total phenolic content (25 +/- 5 mg gallic acid equivalent/100 g of dried extract and total flavonoid content (19 +/- 0.4 mg quercetin equivalent/100 g of dried extract. The extract showed stronger antioxidant activity than the petroleum ether extract, EC50 = 97 +/- 4 mu g/mL in DPPH radical scavenging assay, and EC50 = 258 +/- 15 mu g/mL in ferric reducing antioxidant power assay. In the antiproliferative assay, the petroleum ether extract showed stronger (EC50 = 105 +/- 7 mu g/mL) effect than the aqueous:methanol (20:80, v/v) extract (EC50 = 282 +/- 43 mu g/mL), on hepatocellular carcinoma (HepG2) cells when incubated for 24 h. This is the initial report to demonstrate antioxidant activity and anti-cancer in vitro effect of seed extracts of A. corrorima.