Background: Bistorta amplexicaulis is a seasonal herb with several folkloric uses. The plant
extract has been shown to possess various activities including antioxidant, anticancer, anti-bacterial,
anti-fungal, cardio-protective, and anti-atherosclerosis activities.
Objective: The aim of the study was to quantify the activity of the plant extract and relate it to the
activity of the isolated compound, gallic acid.
Methods: Initially, the plant was extracted, then, the activity of the extract was compared with its
constituent, gallic acid. After this, the cytotoxic potential of the two against human liver cancer cell
line (HepG2), breast cancer cell line (MCF-7) and human umbilical vein endothelial cells (HUVEC)
was evaluated through MTS assay.
Results: The extract had better activity against HepG2 as compared to gallic acid (IC50 29μg/mL vs
37μg/mL). It also provided a better therapeutic window by having lower toxicity for HUVEC cells
than gallic acid (IC50 63μg/mL vs 47μg/mL), suggesting the use of the extract over the purified gallic
acid for these cells. We also performed the fluorescence study of the rhizome extract in ethanol (REE),
methanol (REM), 80% ethanol (80RE), 80% methanol, (80RM) and acetone (RAC). The highest
intensity of fluorescence was found in REE with excitation at 394 nm and emission at 421nm.
Conclusion: The comparison of gallic acid with ethanolic rhizome extract of B. amplexicaulis reveals
important insights about utilizing the plant extract over purified gallic acid. The ethanolic extract also has
the potential to be used as an autofluorescent drug during in vitro and in vivo studies.