Antioxidant activity and polyphenol content of seven medicinal plants of asclepiadaceae - a comparative study

Seven medicinal plants of the family Asclepiadaceae were characterised for their free radical scavenging activity, total polyphenol and flavonoid contents. Antioxidant activity was determined by DPPH (1, 1-diphenyl-2-picryl- hydrazyl) assay method. There was direct correlation between polyphenol content and antioxidant activity (correlation coefficient R2 = 0.6557). IC50 value and total flavonoid content were strongly correlated (correlation coefficient R2 = 0.8337). These plants represent promising sources of natural antioxidants and these findings give scientific bases to their ethno pharmacological uses.