Assessment of Phytochemicals and Antioxidant Properties of Root Extracts of Rubia cordifolia L. in Different Solvent Systems

Rubia cordifolia L. is an important plant used in Ayurvedic and Siddha medicinal systems of India for treatment of blood disorders. Of all the plant parts, roots of R. cordifolia are the most suitable source of effective secondary metabolites. The present work investigated phytochemical content and antioxidant potential of R. cordifolia root powder extracted in different solvents. Total polyphenols and flavonoids content were estimated. High antioxidant activity was corroborated with DPPH, hydrogen peroxide, nitric oxide, reducing power and total antioxidant assays. Obtained results showed that ethanol extracts were most potent over methanol, aqueous and PBS extracts for DPPH, hydrogen peroxide and reducing power assays. In contrast, methanol and aqueous extracts had higher potency in nitric oxide and total antioxidant assays. Encouraging results were obtained for antioxidant activity even upon PVPP treatment that removed the polyphenols from the extracts. The results suggest a potential of ethanol / methanol extracts for anti-cancer cellular activities as many reports earlier have shown that antioxidant activities are closely correlated with anticancer activities.