Figure 2.

evaluation of the cytotoxic effect of black pepper extracts and piperine on K-562 cells. Viability of K-562 cells treated with black pepper extracts [methanol (a, e); ethanol (b, f) and aqueous (c, g)] and piperine (d, h) for varying periods of time, (a–d) 24 h and (e–h) 48 h, thereafter measured by MTT assay. The effect of (i) methanol extract and (j) piperine on the viability of MRC-5 cells after 48 h of treatment. All results are represented as mean ± SEM of three independent experiments. * indicates P < 0.05 as compared with the respective vehicle-treated control group, which was considered as 100 percent in all cases. BP-M, black pepper methanol extract; BP-E, black pepper ethanol extract; BP-Aq, black pepper aqueous extract; PIP, piperine.