Abstract
The aim of this study was to quantify the total phenolic content of Aloe niebuhriana latex extract and validate its antioxidant, hepatoprotective and cytotoxic activity. The total phenolic content of the extract was estimated spectrophotometrically using Folin Ciocalteu method. The antioxidant activity of the latex extract was determined using 2,2-diphenyl-1-picrylhydrazyl free radical scavenging assay. Paracetamol-induced hepatotoxicity rat model was used to evaluate the hepatoprotective activity of the extract. Cytotoxic effect of Aloe niebuhriana latex extract was screened against breast MCF-7, liver HepG2 and colon HCT-116 cancer cell lines using sulphorhodamine B assay. The extract showed high total phenolic content (245.19 mg GAE/g) and strong antioxidant activity (IC50, 19.14 mu g/ml). Aloe niebuhriana extract showed significant decrease in alanine aminotransferase, aspartate aminotransferase and lactate dehydrogenase, as compared to paracetamol-induced hepatotoxicity model. Hepatoprotective potential of Aloe niebuhriana latex extract was significantly (p<0.05) better than that of the control group and silymarin (100 mg/kg/day). Results of the study were well supported by the histopathological observations. Aloe niebuhriana latex extract exhibited a weak cytotoxicity effect against MCF-7, HepG2 and HCT-116 cancer cell lines. The present results provided evidence that the plant extract inhibited hepatotoxicity induced by paracetamol, which was possibly mediated via free radical scavenging and/or inhibition of free radical generation.