Phytochemical content and antioxidant activities of Rhubarb (Rheum emodi)

Medicinal plants have varying natural products and several antioxidants. Antioxidants play a principal function to protect against destruction caused by oxidative stress (OS), Rheum emodi is not an exception, in which it is reported to have compounds that possess antioxidant activity, like polyphenolic compounds. In addition to that, other compounds have proven to have antidiabetic, antimicrobial, antifungal, cytotoxic, hepatoprotective, and nephroprotective activities. This study aimed to quantify the water extract of a powdered plant of R. emodi to evaluate its ability to scavage free radicals. Total phenolic, total flavonoid contents, and reducing ability were measured to consider possible sources of future novel antioxidants in plants. The TPC, TFC, and reducing power assay increased with increasing concentrations of R. emodi. At 1000 µg/ml, the absorbance ranged from 1.437 for TPC, 1.602 for TFC, and 1.638 for reducing power assay, which is more than the absorbance of the standards at the same concentration. The extracted content of reducing power, phenolic, and flavonoid compounds were higher than the standard pyrogallol, quercetin, and ascorbic acid.